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Sample records for jaw edentulous partially

  1. Posterior partially edentulous jaws, planning a rehabilitation with dental implants.

    PubMed

    Monteiro, Douglas R; Silva, Emily V F; Pellizzer, Eduardo P; Filho, Osvaldo Magro; Goiato, Marcelo C

    2015-01-16

    To discuss important characteristics of the use of dental implants in posterior quadrants and the rehabilitation planning. An electronic search of English articles was conducted on MEDLINE (PubMed) from 1990 up to the period of March 2014. The key terms were dental implants and posterior jaws, dental implants/treatment planning and posterior maxilla, and dental implants/treatment planning and posterior mandible. No exclusion criteria were used for the initial search. Clinical trials, randomized and non randomized studies, classical and comparative studies, multicenter studies, in vitro and in vivo studies, case reports, longitudinal studies and reviews of the literature were included in this review. One hundred and fifty-two articles met the inclusion criteria of treatment planning of dental implants in posterior jaw and were read in their entirety. The selected articles were categorized with respect to their context on space for restoration, anatomic considerations (bone quantity and density), radiographic techniques, implant selection (number, position, diameter and surface), tilted and pterygoid implants, short implants, occlusal considerations, and success rates of implants placed in the posterior region. The results derived from the review process were described under several different topic headings to give readers a clear overview of the literature. In general, it was observed that the use of dental implants in posterior region requires a careful treatment plan. It is important that the practitioner has knowledge about the theme to evaluate the treatment parameters. The use of implants to restore the posterior arch presents many challenges and requires a detailed treatment planning.

  2. Posterior partially edentulous jaws, planning a rehabilitation with dental implants

    PubMed Central

    Monteiro, Douglas R; Silva, Emily V F; Pellizzer, Eduardo P; Filho, Osvaldo Magro; Goiato, Marcelo C

    2015-01-01

    AIM: To discuss important characteristics of the use of dental implants in posterior quadrants and the rehabilitation planning. METHODS: An electronic search of English articles was conducted on MEDLINE (PubMed) from 1990 up to the period of March 2014. The key terms were dental implants and posterior jaws, dental implants/treatment planning and posterior maxilla, and dental implants/treatment planning and posterior mandible. No exclusion criteria were used for the initial search. Clinical trials, randomized and non randomized studies, classical and comparative studies, multicenter studies, in vitro and in vivo studies, case reports, longitudinal studies and reviews of the literature were included in this review. RESULTS: One hundred and fifty-two articles met the inclusion criteria of treatment planning of dental implants in posterior jaw and were read in their entirety. The selected articles were categorized with respect to their context on space for restoration, anatomic considerations (bone quantity and density), radiographic techniques, implant selection (number, position, diameter and surface), tilted and pterygoid implants, short implants, occlusal considerations, and success rates of implants placed in the posterior region. The results derived from the review process were described under several different topic headings to give readers a clear overview of the literature. In general, it was observed that the use of dental implants in posterior region requires a careful treatment plan. It is important that the practitioner has knowledge about the theme to evaluate the treatment parameters. CONCLUSION: The use of implants to restore the posterior arch presents many challenges and requires a detailed treatment planning. PMID:25610852

  3. Immediate loading in partially and completely edentulous jaws: a review of the literature with clinical guidelines.

    PubMed

    De Bruyn, Hugo; Raes, Stefanie; Ostman, Pär-Olov; Cosyn, Jan

    2014-10-01

    warranted. Immediately loaded single implants have lower survival rates, of 85.7-100%, with no clear impact of occlusal contact. In fact, a meta-analysis demonstrated a five times higher risk of failure for immediately loaded single implants when compared with delayed loading. No study showed superior soft-tissue preservation or esthetics following immediate loading of single implants compared with other loading protocols. However, this finding may not imply that a provisional implant crown becomes redundant when soft-tissue conditioning is deemed necessary. Taking into account earlier factors for success, immediate loading in the partially edentulous jaw by means of a fixed prosthesis seems predictable in terms of implant survival (95.5-100%). However, there are no studies with data on soft-tissue parameters, esthetic aspects or patient-centered outcomes, and the available studies mainly relate to the load-carrying part of the dentition. Clinical studies focusing on these aspects of treatment outcome are clearly needed. High patient satisfaction is the most important advantage of immediate loading, especially during the early healing phase. In this context, one should also realize that studies have revealed comparable patient satisfaction in patients following delayed loading once their prosthesis is in place. In the decision-making process, this aspect should be properly discussed with the patient along with other advantages and disadvantages of immediate loading. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Implant-supported fixed cantilever prosthesis in partially edentulous jaws: a cohort prospective study.

    PubMed

    Romeo, Eugenio; Tomasi, Cristiano; Finini, Igor; Casentini, Paolo; Lops, Diego

    2009-11-01

    Reconstructive procedures present a higher rate of biological costs due to the necessity of bone harvest and grafts, use of semipermeable barriers etc. On the hand, implant supported cantilever prostheses could allow a simpler rehabilitation procedure. The aim of the present study was to assess the clinical outcome of patients treated with implant-supported fixed partial dentures (FPD) with cantilever after a mean follow-up time of 8 years. The study included 45 consecutive partially edentulous patients treated between January 1994 and August 2006 with 59 partial cantilever fixed prostheses supported by 116 ITI implants. The primary outcome variable considered was the presence of complications at the subject and bridge level; the secondary outcome variable was marginal bone loss (MBL). The frequency of complications was analyzed according to cantilever location and opposite dentition and tested by Fisher's exact test. A multilevel regression model was constructed to analyze the factors influencing MBL with three levels: subject as the highest, and then implant and site. During the follow-up period, 11 implants showed a bone loss exceeding the limit for success, out of which two implants showed an infection of the peri-implant tissue. After an average observation of 8.2 years of cantilever prostheses loading, the implant success and survival rates were 90.5% and 100%, respectively. Besides, the prosthetic success and survival rate were 57.7% and 100%, respectively. None of the predictors included in the multilevel model presented a significant impact on the bone loss between baseline and the follow-up examination. The authors concluded that the prognosis of implant-supported FPDs and marginal bone loss at implants were not influenced by the position or the length of the cantilever, the location of the bridge and type of opposite dentition. Implant-supported fixed cantilever prosthesis can be considered a suitable treatment choice.

  5. Loading protocols and implant supported restorations proposed for the rehabilitation of partially and fully edentulous jaws. Camlog Foundation Consensus Report.

    PubMed

    Schwarz, Frank; Sanz-Martín, Ignacio; Kern, Jaana-Sophia; Taylor, Thomas; Schaer, Alex; Wolfart, Stefan; Sanz, Mariano

    2016-08-01

    The aim of this consensus meeting was to assess whether immediate loading protocols achieve comparable clinical outcomes when compared to conventional loading protocols depending on the type of prosthetic restoration. In addition post-loading implant loss for implant supported prostheses in edentulous jaws was analyzed regarding a potential impact of implant location (maxilla vs. mandible), implant number per patient, type of prosthesis (removable vs. fixed), and type of attachment system (screw-retained, ball vs. bar vs. telescopic crown). Two comprehensive systematic reviews were prepared in advance of the meeting. Consensus statements, practical recommendations, and implications for future research were based on within group as well as plenary scrutinization and discussions of these systematic reviews. The survival rates are high for immediate loaded and conventional loaded implants, but immediate loading may impose a greater risk for implant failure. The estimated implant loss rate is influenced by the implant location, type of restoration, and implant number. Consistent reporting of clinical studies is necessary and high-quality studies are needed to confirm the present results. © 2016 The Authors. Clinical Oral Implants Research Published by John Wiley & Sons Ltd.

  6. The feasibility of immediately loading dental implants in edentulous jaws.

    PubMed

    Henningsen, Anders; Smeets, Ralf; Wahidi, Aria; Kluwe, Lan; Kornmann, Frank; Heiland, Max; Gerlach, Till

    2016-08-01

    Immediate loading of dental implants has been proved to be feasible in partially edentulous jaws. The purpose of this retrospective investigation was to assess the feasibility of immediately loading dental implants in fully edentulous jaws. A total of 24 patients aged between 53 and 89 years received a total of 154 implants in their edentulous maxillae or mandibles. Among the implants, 45 were set in fresh extracted sockets and 109 in consolidated alveolar bones. The implants were provisionally managed with chair-side made provisional resin bridges and exposed to immediate loading. Implants were followed up for 1-8 years, including radiographic imaging. Marginal bone levels were evaluated based on radiographic imaging. A total of 148 out of the 154 implants survived over the follow-up period of 1 to 8 years, giving a survival rate of 96%. The time or region of the implantation, the pre-implant augmentation, and the length and diameter of the implants had no statistically significant influence on the survival or the success rate. The marginal bone level remained stable with only minimal loss of 0.3 mm after 60 months of loading. Within the limitations of this study, immediate loading is feasible for dental implants in edentulous jaws.

  7. The feasibility of immediately loading dental implants in edentulous jaws

    PubMed Central

    2016-01-01

    Purpose Immediate loading of dental implants has been proved to be feasible in partially edentulous jaws. The purpose of this retrospective investigation was to assess the feasibility of immediately loading dental implants in fully edentulous jaws. Methods A total of 24 patients aged between 53 and 89 years received a total of 154 implants in their edentulous maxillae or mandibles. Among the implants, 45 were set in fresh extracted sockets and 109 in consolidated alveolar bones. The implants were provisionally managed with chair-side made provisional resin bridges and exposed to immediate loading. Implants were followed up for 1–8 years, including radiographic imaging. Marginal bone levels were evaluated based on radiographic imaging. Results A total of 148 out of the 154 implants survived over the follow-up period of 1 to 8 years, giving a survival rate of 96%. The time or region of the implantation, the pre-implant augmentation, and the length and diameter of the implants had no statistically significant influence on the survival or the success rate. The marginal bone level remained stable with only minimal loss of 0.3 mm after 60 months of loading. Conclusions Within the limitations of this study, immediate loading is feasible for dental implants in edentulous jaws. PMID:27588213

  8. [Panoramic radiograph in edentulous and partially edentulous patients].

    PubMed

    Angulo, F

    1989-01-01

    A group of two hundred patients from the School of Dentistry, UCV were study using panoramic RX, in order to determined the incidence of impacted roots, impacted teeth, radiographic feature (radiolucent and radiopaque) and foreign body. From the 200 patient 118 (59%) were edentulous and 82 (415) partially edentulous, from of clinically point of view; 40 (20%) were male and 160 (80%) female. From the total sample only 77 (38.5%) showed radiographic feature meanwhile 123 (61.5%) had not any present. Only the patients with radiographic feature were considered and the result according the age were the following: 18 patients 20-40 years old (23.4%); 41 patients 41-60 years old (53.2%) and 18 patients 61-80 years old (23.4%). The higher numbers of feature were observed in the range of age 41-60 years old. In relation to the form there was a predominance of diffuse form (53.3%). However, the size was greater of 5 mm. (43.3%). On the other hand, the higher numbers of feature were observed in the area 456 in the mandible (50%). This findings are in agreement with the result found by Jones & et al (1985) (J. Prosthet Dent 53:535-539). This values are in the same range 20-60% founded in other countries. No significant difference were founded between the partially or totally edentulous patients. This work suggest the important of the panoramic RX as a diagnostic aid before a prosthetic treatment.

  9. Tilted implants for the rehabilitation of edentulous jaws: a systematic review.

    PubMed

    Del Fabbro, Massimo; Bellini, Chiara M; Romeo, Davide; Francetti, Luca

    2012-08-01

    The aim of this review was to evaluate the survival rate of upright and tilted implants supporting fixed prosthetic reconstructions for the immediate rehabilitation of partially and fully edentulous jaws, after at least 1 year of function. An electronic search of databases plus a hand search on the most relevant journals up to December 2009 was performed. The articles were selected using specific inclusion criteria, independent of the study design. The literature search yielded 347 articles. A first screening based on the title and abstract identified 25 eligible studies. After full-text review of these studies, 10 articles were selected for analysis. Seven were prospective single-cohort studies and three had a retrospective design. A total of 462 patients have been rehabilitated with 470 immediately loaded prostheses (257 in the maxilla, 213 in the mandible), supported by a total of 1,992 implants (1,026 upright and 966 tilted). Twenty-five implants (1.25%) failed in 20 patients within the first year. All failures except one occurred in the maxilla. No significant difference in failure rate was found between tilted and upright implants, nor between maxillary and mandibular implants. No prosthesis failure was reported. Limited peri-implant bone loss was reported with no difference between upright and tilted implants. Full patients' satisfaction for function, phonetics, and esthetics was reported in three studies, based on questionnaires. The use of tilted implants to support immediately loaded fixed prostheses for the rehabilitation of edentulous jaws can be considered a predictable technique, with an excellent prognosis in the short-medium term. However, randomized long-term trials are needed to determine the efficacy of this surgical approach. © 2010 Wiley Periodicals, Inc.

  10. Implant assisted ortho-surgery in edentulous jaws: a clinical report

    PubMed Central

    Khojasteh, Arash; Payaminia, Leila; Alikhasi, Marzieh

    2015-01-01

    Key Clinical Message The severely atrophy of jaws often complicates ideally oral reconstruction of esthetics and functionality, and necessitates different preprosthetic surgeries including bone grafting, ortho-surgery, and implant insertion. The mentioned procedures could be done within different approaches. This report describes the management of an edentulous case by implant insertion before orthognathic correction. PMID:26576273

  11. Implant rehabilitation of partial maxillectomy edentulous patient

    PubMed Central

    Gowda, Mahesh E.; Mohan, Murali S.; Verma, Kamal; Roy, I. D.

    2013-01-01

    Edentulous patients with maxillectomy defects present a significant challenge for prosthetic rehabilitation and the adaptive capabilities of the patient as retention is highly compromised. Hence, the option of using endosseous implants to increase obturator retention has been used. A patient of mucormycosis of the left maxilla was treated with surgical excision. After satisfactory healing, definitive implant supported magnet retained prosthesis was fabricated for the patient. Implants with magnetic units offer a practical method of improving the retention of obturators provided acceptable prosthetic protocols are followed for the rehabilitation. PMID:24124314

  12. Patients' preferences towards minimally invasive treatment alternatives for implant rehabilitation of edentulous jaws.

    PubMed

    Pommer, Bernhard; Mailath-Pokorny, Georg; Haas, Robert; Busenlechner, Dieter; Fürhauser, Rudolf; Watzek, Georg

    2014-01-01

    To evaluate patient satisfaction, oral health-related quality of life, and patients' preferences towards minimally invasive treatment options for graftless rehabilitation of complete edentulism by means of dental implants. A MEDLINE search of literature in the English language up to the year 2013 was performed to summarise current evidence from the patient's perspective. The final selection included 37 studies reporting on minimally invasive implant treatment of 648 edentulous maxillae and 791 edentulous mandibles in 1328 patients, via a total of 5766 implants. Patient satisfaction averaged 91% with flapless implant placement (range: 77 to 100%), 89% with short implants, 87% with narrow-diameter implants (range: 80 to 93%), 90% with a reduced number of implants (range: 77 to 100%), 94% with tilted implant placement (range: 58 to 100%), and 83% with zygomatic fixtures (range: 50 to 97%). Indirect comparison yielded patient preference towards tilted implant placement compared to a reduced number of implants (P = 0.036), as well as to zygomatic implants (P = 0.001). While little evidence on patients' preferences towards minimally invasive treatment alternatives vs. bone augmentation surgery could be identified from within-study comparison, it may be concluded that patient satisfaction with graftless solutions for implant rehabilitation of completely edentulous jaws is generally high. Comparative effectiveness research is needed to substantiate their positive appeal to potential implant patients and possible reduction of the indication span for invasive bone graft surgery.

  13. Radiographic findings in the jaws of clinically edentulous old people living at home in Helsinki, Finland.

    PubMed

    Soikkonen, K; Ainamo, A; Wolf, J; Xie, Q; Tilvis, R; Valvanne, J; Erkinjuntti, T

    1994-08-01

    In the present survey the radiographic findings in the jaws of 124 clinically edentulous old people living at home in Helsinki, Finland, were studied, using panoramic radiography supplemented by intraoral radiographs. Only 9% of the subjects had root remains. Impacted teeth were found in 4%, radiolucent lesions in 3%, and radiopaque findings in 13%. Deviations from normal condylar structure were found in 17% and mucosal thickenings in the maxillary sinuses in 7%. The mental foramen was situated at the top of the residual ridge in 42% of the subjects. Topically situated mental foramen and condylar changes were commoner in women. The radiographic oral health status of the population studied was good.

  14. A Retrospective 2-Year Clinical Study of Immediate Prosthetic Rehabilitation of Edentulous Jaws with Four Implants and Prefabricated Bars.

    PubMed

    Sannino, Gianpaolo; Bollero, Patrizio; Barlattani, Alberto; Gherlone, Enrico

    2017-07-01

    The purpose of this retrospective investigation was to evaluate the use of a prefabricated bar system for immediately loaded implants placed and restored according to the All-on-Four concept with up to 24-month follow-up. A total of 51 patients (31 males and 20 females; mean age 63.4 years) presented with edentulous or partially edentulous jaws with severe atrophy of the posterior regions. All patients were treated with full-arch fixed prostheses (28 maxillary, 34 mandibular) each supported by four implants (two vertical, two distally tilted). The implants were immediately loaded with screw-retained full-arch restorations. Each prosthesis was supported by a prefabricated metal bar combined with high-density acrylic resin. Follow-up visits were scheduled at 6, 12, and 24 months after initial prosthetic loading. Intraoral radiographs were obtained immediately after surgery and at each follow-up visit by using a custom radiograph holder and parallel technique. Marginal bone levels were assessed using digital image analysis. Implant and prosthetic survival and success rates were evaluated. Patient satisfaction was further assessed using a 100-mm visual analog scale (VAS). Data were compared by means of the Mantel-Haenszel test. No drop-outs occurred. The overall implant survival rates were 100% and 98.38% for the vertical and tilted implants respectively. Two of the 62 definitive fixed prostheses were lost during the observation period due to implant failure. Since restoration replacement due to implant failure was not judged a prosthodontic failure according to the survival criteria provided in this study, the overall prosthetic survival rate was 100%. No statistically significant differences in marginal bone levels between vertical and tilted implants were detected at 24-month follow-up evaluation in either jaw. All participants were functionally and esthetically satisfied with their definitive restorations after 2 years functioning, as confirmed by the average VAS

  15. MOUTH FLOOR ENLARGEMENTS RELATED TO THE SUBLINGUAL GLANDS IN EDENTULOUS OR PARTIALLY EDENTULOUS PATIENTS. A MICROSCOPIC STUDY

    PubMed Central

    Iwaki, Liogi; Damante, José Humberto; Consolaro, Alberto; Bonachela, Wellington Cardoso; Damante, Carla Andreotti

    2006-01-01

    Mouth floor enlargements (MFE) are observed in edentulous and partially edentulous patients, impairing denture fitting, and have recently been described in the literature as hyperplasias of the sublingual glands. Objective: This study aims at describing the microscopic aspects of MFE that contribute to their final diagnosis. Methods: Twenty-four specimens were surgically removed from the enlarged mouth floor of 19 patients (15 females and 4 males). Patient age ranged from 48 to 74 years, with a mean of 57 years. The main surgical indication was to permit or improve the fitting of dentures. Six patients were completely edentulous and 13 were partially edentulous. The material was processed for microscopic examination and stained with hematoxylin-eosin, Mallory's trichrome and periodic-acid Schiff (PAS). Results and Conclusions: The epithelium of the mouth floor was normal in 17 cases, hyperplastic in 4 and atrophic in 3. Six of the 24 sublingual glands removed were microscopically normal, while the other specimens presented acinar atrophy with hyperplasia of duct-like structures. Interstitial fibrosis was observed in 18 cases and was accompanied by adipose tissue infiltration in 15. Decreased lymphoid tissue was observed in 16 samples and oncocytosis was present in 5 cases. We suggest that MFE in edentulous or partially edentulous patients should be considered as an entity for the text books. PMID:19089274

  16. Digital assessment of preliminary impression accuracy for edentulous jaws: Comparisons of 3-dimensional surfaces between study and working casts.

    PubMed

    Matsuda, Takashi; Goto, Takaharu; Kurahashi, Kosuke; Kashiwabara, Toshiya; Watanabe, Megumi; Tomotake, Yoritoki; Nagao, Kan; Ichikawa, Tetsuo

    2016-07-01

    The aim of this study was to compare 3-dimensional surfaces of study and working casts for edentulous jaws and to evaluate the accuracy of preliminary impressions with a view to the future application of digital dentistry for edentulous jaws. Forty edentulous volunteers were serially recruited. Nine dentists took preliminary and final impressions in a routine clinical work-up. The study and working casts were digitized using a dental 3-dimensional scanner. The two surface images were superimposed through a least-square algorithm using imaging software and compared qualitatively. Furthermore, the surface of each jaw was divided into 6 sections, and the difference between the 2 images was quantitatively evaluated. Overall inspection showed that the difference around residual ridges was small and that around borders were large. The mean differences in the upper and lower jaws were 0.26mm and 0.45mm, respectively. The maximum values of the differences showed that the upward change mainly occurred in the anterior residual ridge, and the downward change mainly in the posterior border seal, and the labial and buccal vestibules, whereas every border of final impression was shortened in the lower jaw. The accuracy in all areas except the border, which forms the foundation, was estimated to be less than 0.25mm. Using digital technology, we here showed the overall and sectional accuracy of the preliminary impression for edentulous jaws. In our clinic, preliminary impressions have been made using an alginate material while ensuring that the requisite impression area was covered. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  17. Mouthguard: a new technique for the partially edentulous patient.

    PubMed

    Gialain, Ivan Onone; e Dias, Reinaldo Brito; Costa, Bruno; Coto, Neide Pena

    2014-10-01

    Over the last decades, several articles have corroborated the need of using mouthguards in sports activities, manufactured with ethylene vinyl acetate (EVA) as their main material. There are different mouthguards techniques used by dentists worldwide to prevent injuries. A technique has been developed to help athletes, especially the partially edentulous patients, who were not getting the proper protection. The mouthguard technique consists in making EVA fillings to improve the adjustment and esthetics of mouthguard used by athletes. It is the authors' conviction that the technique may prevent injuries in sports activities without impairing the athletes' safety and esthetics.

  18. Changing the bonding force of impression tray to edentulous maxillary jaw simulator with impression valve system: in vitro study.

    PubMed

    Akpinar, Y Z; Yilmaz, B; Tatar, N; Demirtag, Z

    2015-01-01

    The aim of this study was to evaluate the effect of an impression valve system (IVS) on the bonding force between an impression tray and an edentulous maxillary jaw. In this in vitro study, a polyether-coated maxillary jaw simulator (PM) was used to model an edentulous maxillary jaw. The IVS was placed into individual impression trays. An irreversible hydrocolloid impression was taken of the PM when the IVS was open and closed. The impression tray bonding force was measured using a digital dynamometer. Student's t-test was used to determine the significance of the difference between these two groups. The impression tray was more easily separated from the PM when the IVS was open (108 ± 3.9 N). The separation was more difficult when the IVS was closed (153.7 ± 14.2 N). The difference between these two findings (P = 0.000) was significant. The use of an IVS facilitates the removal of the impression tray from the mouth when taking impressions from an edentulous maxillary jaw.

  19. Evaluation of the Quantitative Accuracy of 3D Reconstruction of Edentulous Jaw Models with Jaw Relation Based on Reference Point System Alignment

    PubMed Central

    Li, Weiwei; Yuan, Fusong; Lv, Peijun; Wang, Yong; Sun, Yuchun

    2015-01-01

    Objectives To apply contact measurement and reference point system (RPS) alignment techniques to establish a method for 3D reconstruction of the edentulous jaw models with centric relation and to quantitatively evaluate its accuracy. Methods Upper and lower edentulous jaw models were clinically prepared, 10 pairs of resin cylinders with same size were adhered to axial surfaces of upper and lower models. The occlusal bases and the upper and lower jaw models were installed in the centric relation position. Faro Edge 1.8m was used to directly obtain center points of the base surface of the cylinders (contact method). Activity 880 dental scanner was used to obtain 3D data of the cylinders and the center points were fitted (fitting method). 3 pairs of center points were used to align the virtual model to centric relation. An observation coordinate system was interactively established. The straight-line distances in the X (horizontal left/right), Y (horizontal anterior/posterior), and Z (vertical) between the remaining 7 pairs of center points derived from contact method and fitting method were measured respectively and analyzed using a paired t-test. Results The differences of the straight-line distances of the remaining 7 pairs of center points between the two methods were X: 0.074 ± 0.107 mm, Y: 0.168 ± 0.176 mm, and Z: −0.003± 0.155 mm. The results of paired t-test were X and Z: p >0.05, Y: p <0.05. Conclusion By using contact measurement and the reference point system alignment technique, highly accurate reconstruction of the vertical distance and centric relation of a digital edentulous jaw model can be achieved, which meets the design and manufacturing requirements of the complete dentures. The error of horizontal anterior/posterior jaw relation was relatively large. PMID:25659133

  20. In vivo measurements of precision of fit involving implant-supported prostheses in the edentulous jaw.

    PubMed

    Jemt, T

    1996-01-01

    The objective of this study was to measure and compare the precision of fit of implant-supported prostheses in the edentulous jaw by using both the master cast replicas and the intraoral implants as references. Seven maxillary and 10 mandibular prostheses were randomly selected and measured by means of a three-dimensional (3-D) photogrammetric technique. The results indicated that prostheses routinely connected to osseointegrated implants could demonstrate distortion between the framework and individual implants of up to several hundred microns. When master casts were used as a reference, the mean 3-D distortion of the center point of gold cylinders was 37 microns (SD 18) and 75 microns (SD 40) for mandibular and maxillary prostheses, respectively. The corresponding mean displacement was 90 microns (SD 51) and 111 microns (SD 59), respectively, when the intraoral implants were used as references. The mean 3-D distortion was significantly higher for the intraoral measurements in both arches (P < .001 and P < .05). Furthermore, the overall distortion was significantly higher for the maxillary prostheses when the master casts were used as the reference (P < .05). However, for the intraoral measurements, no statistically significant difference of fit between the arches was possible to observe (P < .05). This could possibly be explained by the finding that intraoral measurements of the mandibular prostheses indicated a deformation and rotation of the mandible that was not observed in the maxillary prostheses. A further factor in the lack of statistical significance could be the relatively small sample size.

  1. Implant treatment in edentulous maxillae: a 5-year follow-up report on patients with different degrees of jaw resorption.

    PubMed

    Jemt, T; Lekholm, U

    1995-01-01

    In a retrospective study, 150 patients with edentulous maxillae were selected for treatment with Brånemark implants. The patients were arranged into four different groups, based on jaw shape prior to implant placement. After second-stage surgery, they were provided with either fixed prostheses, removable overdentures followed by fixed prostheses after at least 1 year, or overdentures for the whole period. Patients were followed up for 5 years, with implant and prosthesis survival, annual visits, marginal bone loss, and complications recorded. Results of the study indicated that treatment outcome in edentulous maxillae might be predicted by careful presurgical evaluation of jaw shape. Five-year cumulative implant failure rates varied from 7.9% for patients considered to have enough bone to be provided with fixed prostheses immediately after second-stage surgery to 28.8% for those with severely resorbed jaws receiving an overdenture. The corresponding cumulative prosthesis failure rates were 3.0% and 18.9%, respectively. Patients provided with autogenous bone grafts compared favorably to the group presenting severely resorbed jaws and provided with overdentures, but showed a compromised result compared to the group with the least resorption. Failure of implant treatment correlated significantly with bone quality and ratio of 7-mm implants. All groups, except those treated with bone grafts, showed an average marginal bone level of 1.2 mm after 5 years, irrespective of type of prosthesis. The bone-grafted group showed a corresponding mean level of 2.3 mm after 5 years of function. Regarding clinical complications, a different pattern, mainly related to the type of prosthetic construction used, was observed between the groups. The number of visits clearly indicated that severely resorbed jaws provided with overdentures were the most demanding.

  2. Reconstruction-based Digital Dental Occlusion of the Partially Edentulous Dentition

    PubMed Central

    Zhang, Jian; Xia, James J.; Li, Jianfu; Zhou, Xiaobo

    2016-01-01

    Partially edentulous dentition presents a challenging problem for the surgical planning of digital dental occlusion in the field of craniomaxillofacial surgery because of the incorrect maxillomandibular distance caused by missing teeth. We propose an innovative approach called Dental Reconstruction with Symmetrical Teeth (DRST) to achieve accurate dental occlusion for the partially edentulous cases. In this DRST approach, the rigid transformation between two symmetrical teeth existing on the left and right dental model is estimated through probabilistic point registration by matching the two shapes. With the estimated transformation, the partially edentulous space can be virtually filled with the teeth in its symmetrical position. Dental alignment is performed by digital dental occlusion reestablishment algorithm with the reconstructed complete dental model. Satisfactory reconstruction and occlusion results are demonstrated with the synthetic and real partially edentulous models. PMID:26584502

  3. Immediate occlusal loading in edentulous jaws, CT-guided surgery and fixed provisional prosthesis: a maxillary arch clinical report.

    PubMed

    Drago, Carl; del Castillo, Robert; Peterson, Thomas

    2011-04-01

    Immediate occlusal loading (IOL) in edentulous jaws has been reported in numerous publications with implant cumulative survival rates consistent with conventional, unloaded healing protocols. Computed Tomography (CT)-guided surgery has more recently been developed and accepted as an additional treatment modality for maxillary and mandibular implant placement, with or without IOL. Reports as to the accuracy of planned versus actual implant placement in CT-guided surgeries have indicated that CT-guided surgery is not 100% accurate; standard deviations have been reported with values between 1 and 2 mm in terms of actual versus planned placement. The purpose of this article is to review the clinical parameters associated with IOL, and CT-guided surgery in edentulous jaws; and to present a clinical case illustrating the clinical and laboratory phases of treatment. The illustrated treatment was accomplished with an IOL protocol and includes fabrication and placement of a laboratory-processed provisional maxillary prosthesis. This particular protocol had slightly increased costs relative to conventional implant placement; however, the clinicians and patient benefited from improved accuracy of the provisional prostheses and decreased chairtime for the clinical procedures. The benefits and limitations of this treatment protocol are also discussed.

  4. CNC-milled titanium frameworks supported by implants in the edentulous jaw: a 10-year comparative clinical study.

    PubMed

    Örtorp, Anders; Jemt, Torsten

    2012-03-01

    No long-term clinical studies covering more than 5 years are available on Computer Numeric Controlled (CNC) milled titanium frameworks. To evaluate and compare the clinical and radiographic performance of implant-supported prostheses provided with CNC titanium frameworks in the edentulous jaw with prostheses with cast gold-alloy frameworks during the first 10 years of function. Altogether, 126 edentulous patients were by random provided with 67 prostheses with titanium frameworks (test) in 23 maxillas and 44 mandibles, and with 62 prostheses with gold-alloy castings (control) in 31 maxillas and 31 mandibles. Clinical and radiographic 10-year data were collected for the groups and statistically compared on patient level. The 10-year prosthesis and implant cumulative survival rate was 95.6% compared with 98.3%, and 95.0% compared with 97.9% for test and control groups, respectively (p > .05). No implants were lost after 5 years of follow-up. Smokers lost more implants than nonsmokers after 5 years of follow-up (p < .01). Mean marginal bone loss in the test group was 0.7 mm (SD 0.61) and 0.7 mm (SD 0.85) in the maxilla and mandible, with similar pattern in the control group (p > .05), respectively. One prosthesis was lost in each group due to loss of implants, and one prosthesis failed due to framework fracture in the test group. Two metal fractures were registered in each group. More appointments of maintenance were needed for the prostheses in the maxilla compared with those in the mandible (p < .001). The frequency of complications was low with similar clinical and radiological performance for both groups during 10 years. CNC-milled titanium frameworks are a viable alternative to gold-alloy castings for restoring patients with implant-supported prostheses in the edentulous jaw. © 2009 Wiley Periodicals, Inc.

  5. Main occluding area in partially edentulous patients: changes before and after implant treatment.

    PubMed

    Goto, T; Nishinaka, H; Kashiwabara, T; Nagao, K; Ichikawa, T

    2012-09-01

    The 'main occluding area', the location where food crushing occurs during the first stroke of mastication, is reported to be an important concept; however, it is currently limited to findings in individuals with normal dentition. The purpose of this study was to assess the changes in the location, area and bite force of the main occluding area before and after implant treatments. We enrolled 50 partially edentulous and 22 normally dentate subjects. To identify the location of the main occluding area, each subject was instructed to freely bite once on a dental stopping using the partially edentulous side or the normally dentate area. The location, occluding contact area and bite force of the main occluding area before and after the implant treatments were analysed. The main occluding area was located at a reproducible location in the partially edentulous and normally dentate subjects. This location was principally the first molar region, and for the partially edentulous patients with missing teeth in the molar regions, it moved from the premolar region to the first molar region after treatment. The occluding contact area and bite force for the main occluding area increased (P < 0·05) after the implant treatment in the partially edentulous patients with missing teeth in the molar regions. These results suggest that the main occluding area can be restored to the first molar region after implant treatment and may be an important factor in the assessment of prosthodontic treatment.

  6. Prosthetic Rehabilitation in Partially Edentulous Elders – A Case Report

    PubMed Central

    PICOS, ALINA MONICA; DONCA, VALER; PICOS, ANDREI

    2014-01-01

    Complex treatment involving removable articulated to fixed prostheses is indicated in extended edentulous areas, which represent clinical conditions more frequently encountered in elderly patients. A number of aspects must be considered in elderly patients before starting the therapy: physical and mental condition, self-care capacity, time and cost of treatment, predictability. In institutionalized elders, suffering of systemic diseases, the therapy of choice should be the least invasive and able to restore function at an acceptable level. Active healthy elders can be beneficiaries of complex prosthetic treatments involving many long sessions and difficult treatments. We present a case of a 74 year-old male with extended maxillary edentulous areas, in whom a complex prosthetic treatment was performed. PMID:26528025

  7. Immediate rehabilitation of completely edentulous jaws with fixed prostheses supported by implants placed into fresh extraction sockets and in healed sites: a 4-year clinical evaluation.

    PubMed

    Covani, Ugo; Orlando, Bruno; DʼAmbrosio, Aniello; Sabattini, Vincenzo Bucci; Barone, Antonio

    2012-08-01

    To evaluate the outcome of treatment in the rehabilitation of edentulous jaws with early loaded full-arch screw-retained prostheses after up to 4 years of function. Patients with completely edentulous maxillae and/or mandibles, or presenting natural teeth with a poor or hopeless prognosis, received 6 implants each in the mandible and/or 8 in the upper jaw. All patients received a full-arch prosthetic reconstruction. A total of 19 patients were treated with a total of 164 implants. One hundred nineteen implants were placed immediately after tooth extraction, and 45 implants were placed in healed sites. Overall, 8 implants failed, leading to a 4-year cumulative survival rate of 95.1%. The rehabilitation of the edentulous maxilla and mandible with an early loaded prosthesis represents a viable alternative treatment to classic loading protocols.

  8. Management of long span partially edentulous maxilla with fixed removable denture prosthesis

    PubMed Central

    Jeyavalan, Mahilan I.; Narasimman, M.; Venkatakrishnan, C. J.; Philip, Jacob M.

    2012-01-01

    Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis. PMID:23293488

  9. Six-mm versus 10-mm long implants in the rehabilitation of posterior edentulous jaws: a 5-year follow-up of a randomised controlled trial.

    PubMed

    Romeo, Eugenio; Storelli, Stefano; Casano, Giuseppe; Scanferla, Massimo; Botticelli, Daniele

    2014-01-01

    To compare the clinical outcome of 6-mm and 10-mm long implants in partially edentulous posterior areas. Twenty-four patients, with a partially edentulous area in the jaws with a height and width allowing the positioning of 2 to 3 adjacent 10 × 4.1 mm implants without any augmentation procedure, were randomly allocated according to a parallel group design to receive 6-mm long or 10-mm long implants. A total of 54 implants were placed (26 × 6 mm and 28 × 10 mm implants). Patients were restored 8 weeks after surgery and were followed for 5 years. Outcome measures were prosthesis and implant survival, as well as marginal bone level changes and complications. After 5 years, 18 patients were available. One 6 mm implant failed during the healing period and its related prosthesis could not be placed. No implants were lost after loading. The 6 mm group registered 5 complications (1 mucositis, 3 prosthesis decementations and 1 chipping), while only 3 were registered in the 10 mm group (2 decementations and 1 chipping). The difference in complications between the two groups was not statistically significant (P = 0.39). Marginal bone loss at 5 years was 0.43 and 0.24 mm with the 6 mm and 10 mm groups, respectively (not statistically significant; difference between the two groups 0.19 mm; SD 0.23 mm; 95% CI -0.34;0.73; t test P = 0.42). Implant and prosthetic survival and success rates were similar between prostheses supported by 6-mm or 10-mm long implants.

  10. Evaluation of the accuracy of a common regional registration method for three-dimensional reconstruction of edentulous jaw relation by a 7-axis three-dimensional measuring system.

    PubMed

    Sun, Yuchun; Yuan, Fusong; Li, Hong; Zhao, Yijiao; Lv, Peijun; Wang, Yong

    2014-01-01

    This study was to design a method to quantitatively evaluate three-dimensional (3D) reconstruction accuracy of spatial relationship of dental models based on a 7-axis contact 3D measuring system, and to evaluate the accuracy of a common regional registration method for edentulous jaw relation reconstruction. 3D surface data of edentulous dental casts with 10 positioning cylinders and wax occlusion rims of five patients were obtained using a dental scanner. The jaw relation was reconstructed using the common regional registration in the Geomagic software. Measurements were obtained for line length, vertical distance and horizontal distance between centric points from two sources with upper jaw model base plane as a reference plane. The statistical description of measurement data was done. x ± s of line length, vertical distance and horizontal distance between the center points of each data set were 0.107 ± 0.354, 0.076 ± 0.576 and 0.108 ± 0.530 mm, respectively. Data was analyzed using the paired samples t-test and one-way analysis of variance. Paired t-test results of each patient and one-way analysis of variance for the five patients showed no significant differences (P>0.05). Using the Faro Edge system and standardized positioning cylinders, quantitative evaluation of the 3D reconstruction accuracy of edentulous jaw relation was workable. And results of common regional registration method met clinical requirements.

  11. Orthodontic treatment and implant-prosthetic rehabilitation of a partially edentulous patient.

    PubMed

    Farret, Milton M B; Farret, Marcel Marchiori; Carlesso, Jhosué; Carlesso, Oscar

    2013-10-01

    This article describes the treatment of a 61-year-old man who had a completely edentulous maxillary arch and partially edentulous mandibular arch. The patient was orthodontically treated to correct an anterior crossbite by distalization of the mandibular teeth using a removable prosthesis serving as an anchorage unit. Subsequently, the patient received two zygomatic implants, five conventional implants in the maxillary arch, and six conventional implants in the mandibular arch. By the end of treatment, the convexity of the facial profile improved, and esthetic and functional occlusion was established. © 2013 by the American College of Prosthodontists.

  12. Gingival overgrowth in partially edentulous ridges in an elderly female patient with epilepsy: a case report.

    PubMed

    Dhingra, Kunaal; Prakash, Shobha

    2012-06-01

    Drug-influenced gingival overgrowth is an unaesthetic overgrowth of gingiva principally associated with intake of drugs like phenytoin, cyclosporin A and nifedipine. Its occurrence in both dentate and edentulous regions of oral cavity is poorly understood. This report highlights clinical and histological description, aetiology and management of gingival overgrowth in a partially edentulous (non-denture wearer) 60-year-old female patient with epilepsy on phenytoin and phenobarbital drugs from past 7 years. Patient's intraoral examination revealed lobulated and fibrotic consistency gingival overgrowth around teeth and on partially edentulous ridges of upper and lower arches along with generalised tooth mobility. Under medical consultation, full mouth extraction, surgical excision of overgrowth followed by complete denture rehabilitation and replacement of combination drugs with sodium valproate were accomplished. Histologically, the lesion showed fibro-epithelial hyperplasia. Clinical results after 6 months demonstrated almost complete resolution of gingival overgrowth. The findings of present case suggest that gingival overgrowth can occur even in partially edentulous ridges (not exposed to denture wear) that could be due to persistence of gingival overgrowth, which may not resolve completely following tooth extraction or occurs because of incorporation of specific subpopulation of gingival fibroblasts in alveolar ridge mucosa. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

  13. Clinical accuracy outcomes of closed-tray and open-tray implant impression techniques for partially edentulous patients.

    PubMed

    Gallucci, German O; Papaspyridakos, Panos; Ashy, Linah M; Kim, Go Eun; Brady, Nicholas J; Weber, Hans-Peter

    2011-01-01

    The aim of this research was to compare the accuracy outcomes of open- and closed-tray implant impressions for partially edentulous patients. Eleven partially edentulous spaces in seven patients with two existing implants for fixed partial dentures were included. Group I (closed-tray) and group II (open-tray) were compared using microcomputed tomography scanning. No statistically significant differences were found between the closed- and open-tray techniques (P = .317). The subjective evaluation of patient comfort showed no differences with either impression technique. There were no differences seen between open- and closed-tray impression techniques in partially edentulous patients when implants had less than 10 degrees of angulation.

  14. Cross-arch arrangement in complete denture prosthesis to manage an edentulous patient with oral submucous fibrosis and abnormal jaw relation

    PubMed Central

    Tambe, Abhijit; Patil, Sanjayagouda B; Bhat, Sudhakara; Badadare, Mokshada M

    2014-01-01

    A patient with oral submucous fibrosis and resorbed ridges poses a challenge for prosthodontic rehabilitation because of the limited mouth opening and fibrotic mucosa. The fabrication of prosthesis is very difficult due to abnormal jaw relations, influencing the long-term prognosis of the patient. To present a case of oral submucous fibrosis with severely resorbed edentulous ridges which was successfully managed by adopting a modified technique in fabricating a complete denture prosthesis. A 55-year-old female patient with completely edentulous maxillary and mandibular arches diagnosed with oral submucous fibrosis was rehabilitated with complete dentures by recording neutral zone for resorbed mandibular ridge and by arranging the posterior teeth in cross arch relation for compensation of the abnormal jaw relations. The cross-arch arrangement of posterior teeth provides a more stable and retentive complete denture prosthesis for patients with severely resorbed ridges and a wider mandibular arch. PMID:25239981

  15. Implant and root supported overdentures - a literature review and some data on bone loss in edentulous jaws

    PubMed Central

    2014-01-01

    PURPOSE To present a literature review on implant overdentures after a brief survey of bone loss after extraction of all teeth. MATERIALS AND METHODS Papers on alveolar bone loss and implant overdentures have been studied for a narrative review. RESULTS Bone loss of the alveolar process after tooth extraction occurs with great individual variation, impossible to predict at the time of extraction. The simplest way to prevent bone loss is to avoid extraction of all teeth. To keep a few teeth and use them or their roots for a tooth or root-supported overdenture substantially reduces bone loss. Jaws with implant-supported prostheses show less bone loss than jaws with conventional dentures. Mandibular 2-implant overdentures provide patients with better outcomes than do conventional dentures, regarding satisfaction, chewing ability and oral-health-related quality of life. There is no strong evidence for the superiority of one overdenture retention-system over the others regarding patient satisfaction, survival, peri-implant bone loss and relevant clinical factors. Mandibular single midline implant overdentures have shown promising results but long-term results are not yet available. For a maxillary overdenture 4 to 6 implants splinted with a bar provide high survival both for implants and overdenture. CONCLUSION In edentulous mandibles, 2-implant overdentures provide excellent long-term success and survival, including patient satisfaction and improved oral functions. To further reduce the costs a single midline implant overdenture can be a promising option. In the maxilla, overdentures supported on 4 to 6 implants splinted with a bar have demonstrated good functional results. PMID:25177466

  16. Immediate loading of mandibular dental implants in partially edentulous patients: a prospective randomized comparative study.

    PubMed

    Margossian, Patrice; Mariani, Paul; Stephan, Grégory; Margerit, Jacques; Jorgensen, Christian

    2012-04-01

    While immediate loading in the edentulous mandible is a well-documented procedure, there are limited scientific data on immediate loading in the partially edentulous mandible. Two-year success rates of immediate loading and conventional delayed loading of dental implants in partially dentate mandibles were compared. Patients were randomized into three groups: group A (n = 40), immediate provisionalization with nonocclusal loading; group B (n = 40), immediate provisionalization with occlusal loading; and group C (n = 37), delayed loading with single-stage surgery. Baseline and 2-year measurements included implant stability quotient, insertion torque, and peri-implant bone crest radiography. Two hundred nine implants were immediately loaded in 80 patients. The 2-year success rates were 93.3% for group B and 100% for groups A and C. Immediate provisionalization provided success rates similar to those for delayed loading only when not loaded in occlusion.

  17. Accuracy evaluation of a new three-dimensional reproduction method of edentulous dental casts, and wax occlusion rims with jaw relation.

    PubMed

    Yuan, Fu-Song; Sun, Yu-Chun; Wang, Yong; Lü, Pei-Jun

    2013-09-01

    The article introduces a new method for three-dimensional reproduction of edentulous dental casts, and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method's accuracy in vitro. The method comprises three main steps: (i) acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims; (ii) acquisition of the three-dimensional stereolithography data of jaw relations; and (iii) registration of these data with the reverse engineering software and completing reconstruction. To evaluate the accuracy of this method, dental casts and wax occlusion rims of 10 edentulous patients were used. The lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement tool. The direct data were considered as the true values. The paired-samples t-test was used for statistical analysis. The mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant (P>0.05). Statistical significance among 10 patients was assessed using one-way analysis of variance (P<0.05). The result showed that the 10 patients were considered statistically no significant. Therefore, accurate three-dimensional reproduction of the edentulous dental casts, wax occlusion rims, and jaw relations was achieved. The proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures.

  18. Accuracy evaluation of a new three-dimensional reproduction method of edentulous dental casts, and wax occlusion rims with jaw relation

    PubMed Central

    Yuan, Fu-Song; Sun, Yu-Chun; Wang, Yong; Lü, Pei-Jun

    2013-01-01

    The article introduces a new method for three-dimensional reproduction of edentulous dental casts, and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method's accuracy in vitro. The method comprises three main steps: (i) acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims; (ii) acquisition of the three-dimensional stereolithography data of jaw relations; and (iii) registration of these data with the reverse engineering software and completing reconstruction. To evaluate the accuracy of this method, dental casts and wax occlusion rims of 10 edentulous patients were used. The lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement tool. The direct data were considered as the true values. The paired-samples t-test was used for statistical analysis. The mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant (P>0.05). Statistical significance among 10 patients was assessed using one-way analysis of variance (P<0.05). The result showed that the 10 patients were considered statistically no significant. Therefore, accurate three-dimensional reproduction of the edentulous dental casts, wax occlusion rims, and jaw relations was achieved. The proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures. PMID:23907676

  19. Flapless implant surgery in the edentulous jaw based on three fixed intraoral reference points and image-guided surgical templates: accuracy in human cadavers.

    PubMed

    Widmann, Gerlig; Zangerl, Antoniette; Keiler, Martin; Stoffner, Rudolf; Bale, Reto; Puelacher, Wolfgang

    2010-08-01

    In edentulous patients, accurate and stable positioning of a surgical template is impeded by the mobile mucosal tissue. The objective was to evaluate the accuracy of flapless computer-assisted template-guided surgery in an edentulous human cadaver specimen using three fixed oral reference points (FRP) for fixation of the registration mouthpiece and the consecutive surgical template. Oral implants were planned on the computed tomography (CT) of an edentulous human cadaver specimen. Surgical templates have been fabricated using a multipurpose navigation system. Both the registration mouthpiece and consecutive surgical template were supported via three FRP. Study implants were inserted through the guide sleeves and the accuracy was evaluated on a post-surgical CT of the cadaver jaws fused with the pre-surgical planning CT. A Matlab script enabled comparison of the planned surgical path with the study implants. In five maxillary and three mandibular edentulous human cadaver specimens, a total of 51 implants (35 implants in the maxilla and 16 implants in the mandible) have been placed. The mean+/-standard deviation total error (Euclidean distance)/lateral error (normal deviation) were 1.1+/-0.6/0.7+/-0.5 mm at the implant base and 1.2+/-0.7/0.9+/-0.7 mm at the implant tip. The mean angular error was 2.8+/-2.2 degrees. Flapless surgery based on FRP-supported image-guided surgical templates may provide similar accuracy as reported for tooth-supported surgical templates or surgical navigation.

  20. A radiographic evaluation of cervical bone loss associated with immediate and delayed implants placed for fixed restorations in edentulous jaws.

    PubMed

    Schwartz-Arad, Devorah; Yaniv, Yael; Levin, Liran; Kaffe, Israel

    2004-05-01

    Placement of dental implants is considered a successful and predictable procedure. An important biological benefit is the preservation of bone height following implantation. The purpose of this study was to examine the cervical bone loss (CBL) and its correlation with implant characteristics and anatomic factors, 1 to 8 years post-implantation of immediate and delayed implants. A total of 381 implants (144 immediate and 237 delayed) were placed in 44 edentulous patients (53 jaws) for fixed ceramometal restoration from 1989 to 1996. The mean mesial and distal cervical bone resorption of each implant was measured using panoramic radiographs, by an objective examiner using a computerized scanner before second stage surgery and 1 to 8 years (mean 3.5 years) follow-up. The length of the implant served as an internal standard. The examiner had no prior information on the examined implants. Total CBL was 0.78 +/- 1.22 mm. There was a significant difference (P = 0.049) between CBL of immediate implants compared to delayed ones. Implants > 13 mm showed a significantly (P < 0.001) lower CBL than shorter implants. Hydroxyapatite-coated implants had a higher CBL (P < 0.001) compared to commercially pure titanium implants (P < 0.001). The CBL of maxillary implants was higher than mandibular implants (P < 0.001). Step-wise multiple regression pr.obability tests demonstrated that implant location followed by coating, length, and timing of placement were the most important parameters for implant success (R2 = 0.102). Cervical bone loss around dental implants is influenced by location, coating, length, and implant timing.

  1. Implant prosthodontic management of posterior partial edentulism: long-term follow-up of a prospective study.

    PubMed

    Attard, Nikolai; Zarb, George A

    2002-02-01

    This paper reports on the long-term outcome of implant-supported posterior-zone prostheses in the first 35 consecutive, partially edentulous patients treated in the Implant Prosthodontic Unit (IPU) at the University of Toronto, Toronto, Ontario. A total of 106 Brånemark dental implants were placed in 46 posterior edentulous spans in 35 patients for the management of multiple missing teeth; the patients were followed prospectively. Treatment planning principles involved a minimum of 2 or 3 implants at each edentulous site and scrupulous occlusal prosthodontic designs. The overall survival of posterior implants was 94%. No factors in the patients' history adversely affected implant survival. This clinical update suggests that the use of Brånemark implants in the rehabilitation of patients who are partially edentulous in the posterior zone is highly effective and that survival of the implants is excellent.

  2. Prosthetic rehabilitation and treatment outcome of partially edentulous patients with severe tooth wear: 3-years results.

    PubMed

    Katsoulis, Joannis; Nikitovic, Senka Geissbühler; Spreng, Sophie; Neuhaus, Klaus; Mericske-Stern, Regina

    2011-10-01

    The purpose of this study was to report on the management and treatment outcomes of partially edentulous elderly patients with severe tooth wear. Partially edentulous patients with severe tooth wear who underwent the same protocols for full prosthodontic rehabilitation were eligible for this observational study. Their clinical diagnoses were based on a complete oral examination, photos, functional and cast analysis, general health conditions and behavioural aspects, such as acidic diets and bruxism. A 6-month preliminary phase with splints and provisional prostheses was maintained prior to the final fabrication of fixed and removable prostheses. All patients completed a follow-up period of ≥3years. The outcomes were technical and biological complications with the prosthesis (wear or fracture of anchorage, abutment, prosthesis core or veneering, and implants, plaque index, caries, endodontic and periodontal lesions, tooth fractures and periimplantitis) and oral health-related quality of life (using the oral health impact profile questionnaire, German version of OHIP G-14). Data from 42 patients (33 men, 9 women) with a mean age of 62±8years were available. The probability that a first, second or third technical complication occurred was 49%, 38% and 21%, respectively. About 50% of the patients remained without any complication. The average OHIP-value was 5±7, which represents high oral health-related quality of life. No statistically significant correlations between the OHIP values and the type of prostheses or the occurrence of complications were observed. From multiple perspectives, the rehabilitation of partially edentulous patients with severe tooth wear is a complex task, and more information regarding treatment protocols, prosthetic indications and treatment outcome is needed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Efficacy of soft tissue augmentation around dental implants and in partially edentulous areas: a systematic review.

    PubMed

    Thoma, Daniel S; Buranawat, Borvornwut; Hämmerle, Christoph H F; Held, Ulrike; Jung, Ronald E

    2014-04-01

    To review the dental literature in terms of efficacy of soft tissue augmentation procedures around dental implants and in partially edentulous sites. A Medline search was performed for human studies augmenting keratinized mucosa (KM) and soft tissue volume around implants and in partially edentulous areas. Due to heterogeneity in between the studies, no meta-analyses could be performed. Nine (KM) and eleven (volume) studies met the inclusion criteria. An apically positioned flap/vestibuloplasty (APF/V) plus a graft material [free gingival graft (FGG)/subepithelial connective tissue graft (SCTG)/collagen matrix (CM)] resulted in an increase of keratinized tissue (1.4-3.3 mm). Statistically significantly better outcomes were obtained for APF/V plus FGG/SCTG compared with controls (APF/V alone; no treatment) (p < 0.05). For surgery time and patient morbidity, statistically significantly more favourable outcomes were reported for CM compared to SCTGs (p < 0.05) in two randomized controlled clinical trials (RCTs), even though rendering less keratinized tissue. SCTGs were the best-documented method for gain of soft tissue volume at implant sites and partially edentulous sites. Aesthetically at immediate implant sites, better papilla fill and higher marginal mucosal levels were obtained using SCTGs compared to non-grafted sites. An APF/V plus FGG/SCTG was the best-documented and most successful method to increase the width of KM. APF/V plus CM demonstrated less gain in KM, but also less patient morbidity and surgery time compared to APF/V plus SCTG based on two RCTs. Autogenous grafts (SCTG) rendered an increase in soft tissue thickness and better aesthetics compared to non-grafted sites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Fixed reconstructions in partially edentulous patients using two-part ITI implants (Bonefit) as abutments.

    PubMed

    Brägger, U; Hämmerle, C; Weber, H P

    1990-12-01

    Fixed reconstructions on implant abutments may be a welcome modality in the treatment of partially edentulous patients following the principles of a prophylactically oriented comprehensive care. The option to create artificial tissue integrated abutments widens the range of indications for fixed reconstructions. Risky long-span bridges as well as the preparation of intact teeth for bridge abutments may frequently be avoided. Never should the contours of the prosthesis interfere with the patient's performance of optimal plaque control. Furthermore, supportive periodontal therapy with regular maintenance visits must be provided to optimize a long-term prognosis of the dention as well as the tissue-integrated artificial abutments.

  5. Restoration-Guided Implant Rehabilitation of the Complex Partial Edentulism: a Clinical Report

    PubMed Central

    Tzerbos, Fotios; Tzoras, Vasilios

    2010-01-01

    ABSTRACT Background The hard and soft tissue deficiency is a limiting factor for the prosthetic restoration and any surgical attempt to correct the anatomic foundation needs to be precisely executed for optimal results. The purpose of this paper is to describe the clinical steps that are needed to confirm the treatment plan and allow its proper execution. Methods Team work and basic principles are emphasized in a step-by-step description of clinical methods and techniques. This clinical report describes the interdisciplinary approach in the rehabilitation of a partially edentulous patient. The importance of the transitional restoration which sets the guidelines for the proper execution of the treatment plan is especially emphasized along with all the steps that have to be followed. Results The clinical report describes the diagnostic arrangement of teeth, the ridge augmentation based on the diagnostic evaluation of the removable prosthesis, the implant placement with a surgical guide in the form of the removable partial denture duplicate and finally the special 2-piece design of the final fixed prosthesis. Conclusions Clinical approach and prosthesis design described above offers a predictable way to restore partial edentulism with a fixed yet retrievable prosthesis, restoring soft tissue and teeth and avoiding an implant supported overdenture. PMID:24421964

  6. Implant Restoration of Edentulous Jaws with 3D Software Planning, Guided Surgery, Immediate Loading, and CAD-CAM Full Arch Frameworks

    PubMed Central

    De Riu, Giacomo; Pisano, Milena; Campus, Guglielmo; Tullio, Antonio

    2013-01-01

    Purpose. The aim of this study was to analyze the clinical and radiographic outcomes of 23 edentulous jaws treated with 3D software planning, guided surgery, and immediate loading and restored with CAD-CAM full arch frameworks. Materials and Methods. This work was designed as a prospective case series clinical study. Twenty patients have been consecutively rehabilitated with an immediately loaded implant supported fixed full prosthesis. A total of 120 fixtures supporting 23 bridges were placed. 117 out of 120 implants were immediately loaded. Outcome measures were implants survival, radiographic marginal bone levels and remodeling, soft tissue parameters, and complications. Results. 114 of 117 implants reached a 30 months follow-up, and no patients dropped out from the study. The cumulative survival rate was 97.7%; after 30 months, mean marginal bone level was 1.25 ± 0.31 mm, mean marginal bone remodeling value was 1.08 ± 0.34, mean PPD value was 2.84 ± 0.55 mm, and mean BOP value was 4% ± 2.8%. Only minor prosthetic complications were recorded. Conclusion. Within the limitations of this study, it can be concluded that computer-guided surgery and immediate loading seem to represent a viable option for the immediate rehabilitations of completely edentulous jaws with fixed implant supported restorations. This trial is registered with Clinicaltrials.gov NCT01866696. PMID:23983690

  7. Comparative clinical evaluation of removable partial dentures made of two different materials in Kennedy Applegate class II partially edentulous situation

    PubMed Central

    Hundal, Maninder; Madan, Rajesh

    2015-01-01

    Background Cast Chromium Cobalt alloy has been the material of choice for fabricating Removable Partial Dentures (RPDs) but has certain drawbacks. Newer materials like the flexible Nylon based Super Polyamide have been introduced to overcome these drawbacks. The present study has compared the above two materials for nine clinical parameters. Method The study was carried out on 30 patients presenting with a Kennedy Applegate class II partially edentulous situation who were divided into two equal groups and clinically assessed. Result Statistically significant results were obtained in favor of flexible RPDs, in the parameters of ‘aesthetics’ and ‘overall patient satisfaction’. Both groups showed more or less similar values for ‘frequency of fracture of the prosthesis during usage’ with the incidence being slightly higher for patients wearing the cast RPDs. The clinical parameters of ‘oral soft tissue tolerance’, ‘gingival health’, ‘periodontal health’ and ‘adaptability in areas with undercut’ were statistically at par for all the 30 patients thus suggesting the comparable biocompatibility of the two materials. The highlight of this study was the relative ease in fabrication of the flexible RPDs as compared to the cast RPDs. Conclusion Based on the favorable clinical results of this study, it can be summarized that the flexible RPDs is a viable alternative to cast RPDs in Kennedy Applegate class II partially edentulous situation in the short term. PMID:26843744

  8. Digital versus conventional implant impressions for partially edentulous arches: An evaluation of accuracy.

    PubMed

    Marghalani, Amin; Weber, Hans-Peter; Finkelman, Matthew; Kudara, Yukio; El Rafie, Khaled; Papaspyridakos, Panos

    2017-09-16

    To the authors' knowledge, while accuracy outcomes of the TRIOS scanner have been compared with conventional impressions, no available data are available regarding the accuracy of digital impressions with the Omnicam and True Definition scanners versus conventional impressions for partially edentulous arches. The purpose of this in vitro study was to compare the accuracy of digital implant impressions using 2 different intraoral scanners (IOSs) with that of conventional impressions for partially edentulous arches. Two partially edentulous mandibular casts with 2 implant analogs with a 30-degree angulation from 2 different implant systems (Replace Select RP; Nobel Biocare and Tissue level RN; Straumann) were used as controls. Sixty digital models were made from these 2 definitive casts in 6 different groups (n=10). Splinted implant-level impression procedures followed by digitization were used to produce the first 2 groups. The next 2 groups were produced by digital impression with Omnicam. The last 2 groups were produced by digital impression with the True Definition scanner. Accuracy was evaluated by superimposing the digital files of each test group onto the digital file of the controls with inspection software. The difference in 3-dimensional (3D) deviations (median ±interquartile range) among the 3 impression groups for Nobel Biocare was statistically significant among all groups (P<.001), except for the Omnicam (20 ±4 μm) and True Definition (15 ±6 μm) groups; the median ±interquartile range for the conventional group was 39 ±18 μm. The difference in 3D deviations among the 3 impression groups for Straumann was statistically significant among all groups (P=.003), except for the conventional impression (22 ±5 μm) and True Definition (17 ±5 μm) groups; the median ±interquartile range for the Omnicam group was 26 ±15 μm. The difference in 3D deviations between the 2 implant systems was significant for the Omnicam (P=.011) and conventional (P<.001

  9. Implant-prosthodontic rehabilitation of anterior partial edentulism: a clinical review.

    PubMed

    Krennmair, Gerald; Seemann, Rudolf; Weinländer, Michael; Wegscheider, Walther; Piehslinger, Eve

    2011-01-01

    The aim of this retrospective study was to evaluate implant survival/success rates and peri-implant parameters as well as patient satisfaction for uniformly designed implant-supported anterior maxillary or mandibular fixed partial dentures (FPDs). A retrospective study was conducted on patients with maxillary or mandibular anterior partial edentulism (all incisors missing) treated between 2002 and 2006 with a two-implant-supported four-unit FPD. All FPDs were of the same design: two implant abutments in the lateral incisor positions and two ovate pontics in the central incisor positions. Cumulative implant survival rates and peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index, Periotest values) as well as the incidence and type of prosthodontic maintenance were evaluated. The patients' subjective satisfaction rate was surveyed using multiple questionnaires with a 10-point scoring system (0 = not satisfied to 10 = highly satisfied). Thirty-six of 38 patients (dropout: 5%) with 72 implants (50 maxillary and 22 mandibular implants, 25 maxillary and 11 mandibular FPDs) were available for follow-up after a mean observation period of 56.2 ± 10.3 months. High cumulative implant survival and success rates (100%) and healthy peri-implant parameters (mean marginal bone resorption: 1.8 ± 0.3 mm; mean pocket depth: 2.5 ± 1.0 mm; Periotest value: -4.5 ± 1.1; and Plaque/Bleeding/Gingival indices of 0 in 70% of sites [with significantly better results in the maxilla than in the mandible]) were achieved. The most frequent required prosthodontic maintenance efforts were maxillary recementation (3/25; 12%) and mandibular rebasing (2/11; 18.2%). A high score for satisfaction was obtained, although slightly better overall results were seen for maxillary than for mandibular FPDs. For all parameters evaluated, these FPDs proved to be a viable treatment procedure for anterior partial edentulism with good clinical and esthetic

  10. Digital approach to planning computer-guided surgery and immediate provisionalization in a partially edentulous patient.

    PubMed

    Arunyanak, Sirikarn P; Harris, Bryan T; Grant, Gerald T; Morton, Dean; Lin, Wei-Shao

    2016-07-01

    This report describes a digital approach for computer-guided surgery and immediate provisionalization in a partially edentulous patient. With diagnostic data obtained from cone-beam computed tomography and intraoral digital diagnostic scans, a digital pathway of virtual diagnostic waxing, a virtual prosthetically driven surgical plan, a computer-aided design and computer-aided manufacturing (CAD/CAM) surgical template, and implant-supported screw-retained interim restorations were realized with various open-architecture CAD/CAM systems. The optional CAD/CAM diagnostic casts with planned implant placement were also additively manufactured to facilitate preoperative inspection of the surgical template and customization of the CAD/CAM-fabricated interim restorations. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  11. Implant prosthodontic management of anterior partial edentulism: long-term follow-up of a prospective study.

    PubMed

    Zarb, John P; Zarb, George A

    2002-02-01

    This paper reports on the long-term outcome of patients with Kennedy Class IV partial edentulism treated in the Implant Prosthodontic Unit (IPU) at the University of Toronto, Toronto, Ontario. The information for this paper was gathered from the charts of the first 30 consecutive, partially edentulous patients treated at the IPU. These patients all had Class IV edentulism and formed part of the original prospective clinical studies that were initiated in 1983. The patients' dental history suggested maladaptive experiences with traditional removable prostheses or a reluctance to have intact or quasi-intact teeth prepared as retainers for fixed prostheses. Fifteen men and 15 women treated with 94 Br nemark dental implants, supporting 34 prostheses, were followed until June 2000 (25 patients) or until they were lost to follow-up (5 patients). The multiple missing teeth occurred in 19 maxillae and 15 mandibles. The original prosthodontic treatments were intended to result in 33 fixed partial prostheses and 1 overdenture. At the time of this report, 25 patients with 86 implants supporting 31 fixed prostheses and 3 overdentures had been followed for an average of 12 years (range 7 16 years). The overall survival of implants was 92%. The difference between men (94%) and women (89%) was not statistically significant. This report is an interim update on an ongoing long-term prospective study. The results so far demonstrate a high survival rate for Br nemark implants supporting tissue-integrated prostheses for the management of anterior partial edentulism.

  12. Biologic outcome of implant-supported restorations in the treatment of partial edentulism. Part 2: a longitudinal radiographic study.

    PubMed

    Naert, Ignace; Koutsikakis, George; Quirynen, Marc; Duyck, Joke; van Steenberghe, Daniel; Jacobs, Reinhilde

    2002-08-01

    The purpose of this study was to evaluate over time the marginal bone level changes around implants installed to treat partial edentulism and to investigate the possible effect of several confounding variables. Consecutive intraoral radiographs taken with the paralleling technique were used. In all, 660 partially edentulous patients ever treated in the departments (248 males; 15-83 years of age) with 1655 implants, which were successfully integrated at abutment connection, were loaded by means of fixed partial prostheses. The observation period starting at abutment connection reached 16 years (mean 5.1). Implants were divided into three groups: 235 implants supported single-tooth crowns, 398 supported implant-tooth connected and 1022 free-standing fixed partial prostheses. Implants were placed in maxilla and mandible, both anteriorly and posteriorly. No significant difference in bone level evolution was predicted between the three groups of implants, either for posterior or for anterior sites. The estimated marginal bone loss for the first 6 months is 0.31 mm/year and after that 0.015 mm/year higher in the maxilla than in the mandible. More bone loss was predicted for the first 6 months when dehiscences existed, when a membrane or a bone graft were used, or when metal/ceramic prosthesis material was applied. Age and gender did not affect the change in bone level. The use of subsequently situated single-implant crowns to restore an edentulous space did not lead to more marginal bone loss than around splinted implants. Based on marginal bone height maintenance, the excellent prognosis of the presently used implants to support restorations in the treatment of partial edentulism was confirmed.

  13. Prevalence and pattern of partial edentulism among dental patients attending College of Dentistry, Aljouf University, Saudi Arabia

    PubMed Central

    Fayad, Mostafa I.; Baig, Mohamed N.; Alrawaili, Abdulrazaq M.

    2016-01-01

    Objective: The current study aimed to determine the prevalence and pattern of partial edentulism among dental patients attending the College of Dentistry, Aljouf University, Saudi Arabia. Patients and Methods: A total of 142 patients were selected, and the prevalence of partial edentulism among the selected patient was recorded. Patients were grouped into three age groups; Group I: 21–30 years, Group II: 31–40 years, and Group III: 41–50 years. Kennedy's classification was used to determine the pattern of partially edentulous arches. Modification areas were not included in the assessment to avoid complexity. Data was analyzed using the Statistical Package for the Social Sciences version 20.0 for windows. Results: The results showed that the occurrence of Kennedy Class III partial edentulism was 67.2 % in the maxillary arch and 64.1% in the mandibular arch. Followed by Class II in both maxillary and mandibular arch with an average of 16.3 % in maxillary arch and14.8% in the mandibular arch. Based on these results, class III has the highest prevalence in group II (31- 40 years). Class I and class II have the highest incidence among group III Patients (41–50 years). Conclusions: Among selected patients, Class III dental arch was the most prevalent pattern in maxillary and mandibular arches. Class IV being the least dominant pattern between all classes. There are a rise in Kennedy Class I and Kennedy Class II pattern and a decline in Class III and Class IV with an increase in age. PMID:28217535

  14. Recording Myocentric Relation in a Partially Edentulous Patient: A Case Report

    PubMed Central

    Manchanda, Sunny; Bhawsar, Sanjay Vasant; Manchanda, Jyoti; Ramchandani, Amit

    2015-01-01

    The masticatory system constitutes four closely interrelated components: Teeth, muscles, nerves, and temporomandibular joints (TMJ). The stable and physiologic rest position of the TMJ is based on the muscle guidance (mainly masticatory, and partially facial), neurally determined and controlled occlusion, integrated together with its peripheral proprioceptors and relax mechanism of the central nervous system. Oral rehabilitation procedures should emphasize on a holistic approach to establish a physiologic relationship of the lower jaw to the base of the cranium resulting in a neuromuscular rest position. This position then would support an occlusion for the stability of the TMJ, the masticatory muscles of the orofacial region and the teeth along with their supporting periodontium. Such a holistic approach becomes more important in cases where the patient not only requires oral rehabilitation but also presents with related TMJ problems. This is a case report where an attempt is made to rehabilitate a patient in a neuromuscular rest position by establishing a myocentric relation. PMID:26668492

  15. [Detection of masticatory muscle in bilateral distal-extension partially edentulous patients before and after prosthetic rehabilitation by surface electromyography].

    PubMed

    Yu, Chu-Hua; Chen, Yu-Qin; Zhang, Fu-Qiang

    2006-10-01

    To analyze the difference of masticatory muscle in bilateral distal-extension partially edentulous patients before and after prosthetic rehabilitation by surface electromyography. Twenty-seven bilateral distal-extension partially edentulous patients were randomly selected, and be detected before and after prosthetic rehabilitation by surface electromyography. During the detection, the amplitudes of the anterior temporalis and masseter muscle were registered. Using them, the asymmetry index of total, asymmetry index of the masseter, asymmetry index of the anterior temporalis and mastication index were calculated. Student's t test was used to analyze the results. The asymmetry index of total and asymmetry index of the masseter in group of one month after prosthetic rehabilitation increased significantly than that in the group before prosthetic rehabilitation (P < 0.05); The asymmetry index of total and asymmetry index of the anterior temporalis in group of three or six months after prosthetic rehabilitation decreased significantly than that in the group before prosthetic rehabilitation (P < 0.05); The mastication index decreased gradually after prosthetic rehabilitation, the difference was also be significant between group of three or six months after prosthetic rehabilitation and group before prosthetic rehabilitation (P < 0.05). After prosthetic rehabilitation, the equation and reservation of muscle's energy in bilateral distal-extension partially edentulous patients were significantly better than before. Whereas it costed more than three months for patients to adapt the dentures.

  16. Rotational path removable partial denture (RPD): conservative esthetic treatment option for the edentulous mandibular anterior region: a case report.

    PubMed

    Suh, Jennifer S; Billy, Edward J

    2008-01-01

    It can be esthetically and financially daunting for patients to lose teeth in an anterior region of the mouth. For these patients, traditional treatment options presented in the past have included fixed partial denture, implants, and conventional removable partial denture (RPD). For patients faced with financial, anatomical, and/or esthetic limitations, the edentulous region can be restored successfully with a rotational path RPD. Rotational path RPD designs have often been overlooked by the dental profession due to its complex concepts involving the prosthetic design and sensitive laboratory techniques. With better understanding of the concepts and design, the dental clinician can deliver the highest esthetic outcome in compromised areas in which other treatment options may often face limitations. This paper reviews the method used to esthetically design and plan a posterior-anterior rotational path RPD in an edentulous mandibular anterior region for a patient missing the mandibular incisors. Due to inadequate understanding of the mechanics of rotational path RPDs, many clinicians have not adapted the application of this advantageous prosthesis. When correctly designed and fabricated, the rotational path RPD provides improved esthetics, cleanliness, and retention for patients who may not be suitable candidates for implants or fixed partial dentures in tooth-supported edentulous regions.

  17. Mucosal topography around implants in edentulous upper jaws. Photogrammetric three-dimensional measurements of the effect of replacement of a removable prosthesis with a fixed prosthesis.

    PubMed

    Jemt, T; Book, K; Lie, A; Börjesson, T

    1994-12-01

    A photogrammetric technique was tested to measure the topography of the mucosa around implants, placed in edentulous upper jaws. Photographs were taken of casts from 6 patients, who all had used a removable overdenture for one year. Another series of photographs was taken on new casts after the use of a fixed prosthesis for a second year. The 6 pairs of photographs were measured and compared in an analytical stereo plotter for surface contour and implant positions. The results from the measurements indicated a trend of general recession of the mucosa after one year with fixed prosthesis, both on the buccal as well as on the palatal side. The mean volume of recession was 222.4 mm3, corresponding to an average of 0.4 mm3/mm2 of mucosa. More recession was generally observed on the palatal side, but obvious variations between the patients were present. In conclusion, the photogrammetric technique was considered to be well suited for analysing tissue contours in various dental situations.

  18. Computed tomography and partial coronoidectomy for open-mouth jaw locking in two cats.

    PubMed

    Soukup, Jason W; Snyder, Christopher J; Gengler, William R

    2009-01-01

    Open-mouth jaw locking in the cat has traditionally been minimally evaluated with diagnostic imaging. Multiple methods have been described for surgical management of this problem. This report describes the use of computed tomography to diagnose open-mouth jaw locking in 2 cats secondary to ventrolateral displacement of the coronoid process in relation to the zygomatic arch. In these 2 cases, a previously unreported surgical approach whereby the coronoid was not reduced before partial coronoidectomy was used with successful outcomes.

  19. Comparison between inflammation-related markers in peri-implant crevicular fluid and clinical parameters during osseointegration in edentulous jaws.

    PubMed

    Bielemann, Amália M; Marcello-Machado, Raissa M; Leite, Fábio Renato Manzolli; Martinho, Frederico Canato; Chagas-Júnior, Otacílio Luiz; Antoninha Del Bel Cury, Altair; Faot, Fernanda

    2017-07-14

    The aim of this study is to improve the understanding of interleukin mechanisms during osseointegration to enhance the monitoring of implant failure and success. Clinical parameters, implant stability, and cytokine levels in peri-implant crevicular fluid (PICF) during early bone healing after implant placement were investigated. Sixty narrow implants were placed in mandible anterior region of 30 edentulous patients (67.23 ± 7.66 years). Bone type, insertion torque, and primary stability were registered during surgery. Clinical measurements of peri-implant health and the secondary implant stability quotient (ISQ) were recorded. Samples from the PICF were collected 1, 2, 4, 8, and 12 weeks after surgery and analyzed for IL-1β, IL-6, IL-10, and TNF-α levels using ELISAs. The gingival index increased significantly during the first week (p = 0.05), while the plaque index increased significantly between 4 to 8 and 8 to 12 weeks (p < 0.05). The probing depth and the ISQ also reduced significantly (p < 0.05) over time. The TNF-α release increased significantly after the 2nd week for non-atrophic patients and 4th week for atrophic patients (p < 0.05). The IL-1β concentrations showed a short-lived peak after 1st week (p = 0.003), specially in atrophic patients and sites with bone type I (p = 0.034; p = 0.007). The IL-6 concentrations peaked during the 1st and 2nd weeks (p < 0.05; p = 0.005) in atrophic patients and in bone type II (p = 0.023; p = 0.003). The IL-10 concentrations increased gradually over time, showing the highest concentrations at the 12th week (p < 0.005). A total of 12 implants failed at different periods. While the clinical measurements presented differences between the evaluation periods, these were not indicative of early dental implant failure or peri-implant diseases. Smoking, bone atrophy, and bone type can greatly influence the cytokines concentrations during the healing time.

  20. The Effect of Ridge Expansion on Implant Stability in Narrow Partially Edentulous Ridges - A Preliminary Clinical Study

    PubMed Central

    Shaik, Latheef Saheb; Meka, Sridhar; Chakravarthi, Srinivas Pandi; Kolli, Naga Neelima Devi; Lingamaneni, Krishna Prasad; Avvaru, Susmita; Tiwari, Rahul

    2016-01-01

    Introduction Currently, dental treatments with better aesthetic results and less treatment time is more acceptable by the patients. Inadequate amount of bone for implant placement at functionally and aesthetically most appropriate position is a common problem. Aim To assess the effect of ridge expansion on implant stability in narrow partially edentulous ridges and to evaluate clinically and radiographically the success of dental implants, placed immediately following ridge expansion procedure. Material and Methods Ten participants (nine males, one female, average age - 28 years) with partial edentulism associated with narrow atrophic alveolar ridges with adequate height and willing to participate in the study were included. The ridge expansion was performed using osteotomes and simultaneous implant placement was done. A total of 10 implants were placed. Stability, achieved ridge width and radiographic crestal bone loss were assessed three months post-operatively. Results Three months follow-up revealed stable implants both clinically and radiographically. All 10 implants were surrounded by adequate amount of bone required for successful functional rehabilitation. Conclusion The study reveals that the technique of ridge expansion using osteotomes is successful in horizontal expansion, in cases of atrophic alveolar ridges thus, eliminating the need for more complex treatment as well as reduces the rehabilitation time along with improving the quality of bone support. PMID:27790575

  1. Immediate Implant Loading in Compromised Maxillary Partially Edentulous Arch- A Case Report

    PubMed Central

    Ramesh, Sachhi; Patil, Veena; Jain, Anoop; Gaddale, Reetika

    2014-01-01

    As the aesthetic demands are increasing day by day, demand of immediate restoration or replacement of teeth is also increasing. Because of this, immediate implant placement, along with immediate loading of implant, is a favourite treatment option for patients as well as dentists. This case report discusses the immediate implant loading in compromised maxillary anterior region, in which patient got immediate restoration of edentulous area. More importantly, from the patients’ points of view, immediate loading can produce positive social and psychological effects. PMID:24959519

  2. Relationship of central incisor implant placement to the ridge configuration anterior to the nasopalatine canal in dentate and partially edentulous individuals: a comparative study

    PubMed Central

    2015-01-01

    Background. The aims of this study were to investigate the ridge contour anterior to the nasopalatine canal, and the difference between the incidences of the nasopalatine canal perforation in dentate and partially edentulous patients by cone-beam computed tomography. Methods. Cone-beam computed tomography scan images from 72 patients were selected from database and divided into dentate and partially edentulous groups. The configuration of the ridge anterior to the canal including palatal concavity depth, palatal concavity height, palatal concavity angle, bone height coronal to the incisive foramen, and bone width anterior to the canal was measured. A virtual implant placement procedure was used, and the incidences of perforation were evaluated after implant placement in the cingulum position with the long axis along with the designed crown. Results. Comparing with variable values from dentate patients, the palatal concavity depth and angle were greater by 0.9 mm and 4°, and bone height was shorter by 1.1 mm in partially edentulous patients, respectively. Bone width in edentulous patients was narrower than in dentate patients by 1.2 mm at incisive foramen level and 0.9 mm at 8 mm subcrestal level, respectively. After 72 virtual cylindrical implants (4.1 × 12 mm) were placed, a total of 12 sites (16.7%) showed a perforation and three-fourths occurred in partially edentulous patients. After replacing with 72 tapered implants (4.3 × 13 mm), only 6 implants (8.3%) broke into the canal in the partially edentulous patient group. Conclusions. The nasopalatine canal may get close to the implant site and the bone width anterior to the canal decreases after the central incisor extraction. The incidence of nasopalatine canal perforation may occur more commonly during delayed implant placement in central incisor missing patients. PMID:26557434

  3. Prosthodontic treatment in a partially edentulous patient with a complex medical history of epilepsy and deep vein thrombosis: a case report.

    PubMed

    Kosyfaki, Panagiota; Woerner, Wolf; Att, Wael

    2011-05-01

    This report describes the prosthodontic rehabilitation of a partially edentulous patient by means of a maxillary implant-supported removable dental prosthesis and mandibular telescopic crown prosthesis. Due to the patient's contributory medical history for epilepsy and deep vein thrombosis, clinical management considerations are outlined along with an evidence-based, medically oriented treatment sequence concerning the surgical and prosthodontic stages of the case.

  4. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 1: two example cases of a combined fixed-removable restoration].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    After a careful diagnosis, treatment planning and pretreatment, two partially edentulous patients were restored partly by onlays, crowns and bridges, partly by removable prostheses. According to esthetic and functional demands all- and/or metal-ceramic restorations were used as well as cast frame prostheses with clasps or extracoronal attachments.

  5. A Survey of Removable Partial Denture (RPD) Retentive Elements in Relation to the Type of Edentulism and Abutment Teeth Found in Commercial Laboratories, Athens, Greece.

    PubMed

    Polychronakis, Nick; Sotiriou, Michael; Zissis, Alcibiades

    2014-09-01

    The aim of this survey was to record removable partial denture (RPD) retentive elements and abutment teeth in partially edentulous patients, identified in commercial laboratories in Athens, Greece. 628 master casts with the corresponding cast metal frameworks used in the construction of RPDs were evaluated. Casts were photographed to identify the number and position of existing teeth, the partial edentulism class and the retentive elements. Prevalence tables and the x(2) test were used for the statistical analysis of the collected data (α=.05). There were 276 maxillary (43.9%) and 352 (56.1%) mandibular casts. Maxillary edentulism entailed almost a total absence of right third molars in 96.7% and left third molars 96.0% of casts, with lower rates for the first and second molars. Edentulism in the posterior mandible presented a similar pattern. The most profound findings concerning retentive elements were: 91.9% of the retainers used were clasps and the remaining 8.1% were attachments. Of the clasps used, 48.9% were of the Roach Τ type, a finding more common in Kennedy Class I as compared to other Kennedy Classes (p<0.01). The circumferential clasps accounted for 19.3% of the total clasps used, and it was less frequently presented (8.8%) in Kennedy I Classes (p<0.01). Roach clasps were used in the majority of cases whereas RPI clasps and attachments were rarely used.

  6. Oral health related quality-of-life outcomes of partially edentulous patients treated with implant-supported single crowns or fixed partial dentures

    PubMed Central

    2017-01-01

    Background Oral health-related quality of life (OHRQoL) is afflicted by different variables. Limited information is available regarding the impact of different phases of implant therapy on OHRQoL of edentulous patients. This study was carried out to assess the OHRQoL of patients treated with implant-supported single crowns or fixed partial dentures. Material and Methods A total of 79 healthy partially edentulous subjects needing implant therapy were incorporated in this study. Before placement of the implants, the subjects were instructed to fill the original version of OHIP questionnaire. Subsequently patients received titanium oral implants of the ITI® Dental Implant System. After 1st, 2nd and 3rd year of implant placement, patients filled the same OHIP-49 questionnaire. In this manner the impact of implant therapy on OHRQoL by putting in comparison pre- and post-treatment OHIP-49 scores was assessed. Statistical analyses were performed using Statistical Package for the Social Science software (SPSS, version 22, Chicago, IL, USA). Paired t test and Unpaired t test were performed and a statistical significance was set at 5% level of significance (p<0.05). Results Functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability were significantly decreased from baseline to 1st year (p<0.05) except handicap (p>0.05). All variables were also significantly decreased from baseline to 2nd year and 3rd year (p<0.05). There were no significant differences dependent on gender with respect to OHIP (p>0.05). Patients aged less than 60 years and more than 60 years of age groups differed significantly with respect to OHIP scores measured at 1st year, 2nd year and at 3rd year of implant placement (p<0.05). Conclusions Decrease in pre- and post-treatment OHIP scores OHIP demonstrated the significant increase in the OHRQoL after the therapy, which suggested increased levels of patient satisfaction. Key words:Edentulism

  7. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients.

    PubMed

    Dolcini, Giorgio Andrea; Colombo, Marco; Mangano, Carlo

    2016-01-01

    Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results.

  8. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients

    PubMed Central

    2016-01-01

    Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results. PMID:27493665

  9. Aesthetic considerations for the treatment of partially edentulous patients with removable dentures.

    PubMed

    Budtz-Jørgensen, E; Bochet, G; Grundman, M; Borgis, S

    2000-10-01

    Treatment with removable partial dentures (RPDs) is an affordable solution for anterior or posterior tooth loss. In determining a proper treatment solution, it is important for the clinician to consider the patient's aesthetic expectations, socioeconomic situation, and the prognosis for the prosthesis and remaining dentition. This article presents guidelines to optimize the aesthetic result of this treatment and considers framework and clasp concepts; rotational path design; minimal extension of the denture bases; auxiliary attachments or retentive bars; and implants for retention and support of RPDs.

  10. Oral health-related quality of life in partially edentulous patients before and after implant therapy: a 2-year longitudinal study

    PubMed Central

    BRAMANTI, E.; MATACENA, G.; CECCHETTI, F.; ARCURI, C.; CICCIÙ, M.

    2013-01-01

    SUMMARY Objectives. The aim of this study was to measure the Oral Health-Related Quality of Life (OHRQoL) before and after a prosthodontic implant therapy so to determine the physical and psychological impact of implant-supported fixed partial dentures (IFPD) rehabilitation among edentulous patients. Methods. 50 partially edentulous patients aged 40–70 years, treated with IFPD, completed the OHRQoL questionnaire before the implant surgery (Time 0) and 2 years after their whole implant-prosthetic rehabilitation (Time 1). The questionnaire was proposed in a short version of Oral Health Impact Profile (OHIP-14, range 0–56) and analyzed through the ‘additive method’. We evaluated statistical mean, standard deviation, median, variance and mode of all OHIP-14 domains and the statistical significance about oral changes at Time 0 and Time 1 using the Chi-square test (p-values < 0.05). Results. Patients reported significant changes in mean OHIP scores (Time 0: 2.15; Time 1: 0.65; p < 0.01). The most prevalently affected domain was “functional limitation”, followed by “psychological discomfort” and “physical pain”. There were no significant differences dependent on age, gender and antagonistic teeth (p > 0.05). Patients with I and IV Kennedy’s class edentulism showed better improvement (p < 0.05). Conclusions. Preoperative and post-treatment assessments of OHRQoL exhibited significant differences. The IFPD treatment had a positive effect on the OHRQoL, which improved better in patients with I and IV Kennedy’s edentulous class. PMID:24175052

  11. Computer-guided implant surgery and immediate loading with a modifiable radiographic template in a patient with partial edentulism: A clinical report.

    PubMed

    Lanis, Alejandro; Padial-Molina, Miguel; Gamil, Rami; Alvarez del Canto, Orlando

    2015-09-01

    Computer-guided implant surgery in fresh extraction sites is an underdeveloped procedure. The presence of teeth that will be extracted makes the creation of an appropriate radiographic template for virtual simulation of the rehabilitation impossible. A modified radiographic template is presented to define a digital restorative simulation for the maxillary rehabilitation of a patient with partial edentulism. This modification enables 3-dimensional prosthetic virtual information in regions where teeth will be extracted. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Platform switching vs standard implants in partially edentulous patients using the Dental Tech Implant System: clinical and radiological results from a prospective multicenter study.

    PubMed

    Del Fabbro, Massimo; Bianchessi, Carlo; Del Lupo, Riccardo; Landi, Luca; Taschieri, Silvio; Corbella, Stefano

    2015-12-01

    The main objective of this study was to evaluate clinical and radiographic outcomes of implant-supported fixed partial prostheses, comparing platform switching and standard platform concepts. Patients with single or multiple partial edentulism were included in this prospective multicenter study. Success rate, as well as crestal bone loss and occurrence of complications were evaluated over time, for a minimum of 3 years after prosthesis delivery. Radiographic and clinical examination served to evaluate implant and prosthesis conditions. A total of 51 patients with 117 implants (55 in the centralized platform group and 62 in the standard platform group) were considered in the analysis. After 3 years of loading, the cumulative implant survival in test group was 90.3 %, while in the control group, it was 96.5 % without any statistically significant difference. After 3 years of function, the bone loss was 0.33 ± 0.19 mm in the test group and 0.48 ± 0.26 mm, revealing a significant difference. Platform switching concept may lead to a reduction of marginal bone loss over time if compared to standardized one. Such effect seemed not to be related to a reduction of overall success rate of the treatment. Platform switching could be a viable prosthetic option for implant treatment of partial edentulism.

  13. Edentulism in Brazil: trends, projections and expectations until 2040.

    PubMed

    Cardoso, Mayra; Balducci, Ivan; Telles, Daniel de Moraes; Lourenço, Eduardo José Veras; Nogueira Júnior, Lafayette

    2016-04-01

    The aim of this study was to examine the edentulism rates in Brazil and make projections for the next years. Data were collected from three national oral health surveys. The percentage of edentulous jaws was calculated. Projections were made for the years 2020, 2030 and 2040, assuming that edentulism follows a logistic function. Population projections were also performed. Annual change in proportion of edentulous jaws was -0.04% for teenagers, -0.96% for adults and 0.76% for the elderly. By 2040, edentulous jaws will be virtually zero among teenagers, 1.77% among adults and 85.96% among the elderly. Teenagers will slightly decrease in number; adults will increase and subsequently decrease; the elderly will continue to increase. In teenagers and adults, the number of edentulous jaws will decrease, being approximately 616,000 in 2040. In the elderly, it will increase alarmingly, reaching over 64 million in 2040. Edentulism is declining in Brazil among teenagers and middle-aged adults, but is still increasing and will continue to increase for the next decades among the elderly.

  14. Rehabilitation of long-span Kennedy class IV partially edentulous patient with a custom attachment-retained prosthesis

    PubMed Central

    Shetty, Pavithra Kumar; Shetty, Bharath Y; Hegde, Mayur; Prabhu, Bharath M

    2016-01-01

    The rehabilitation of a patient in the Kennedy class IV situation demands biomechanical balance and aesthetic improvement. The long-span condition complicates the problem because of the unavailability of sufficient number of abutments to support the prosthesis. Conventional removable prosthesis and fixed partial denture are not advised for the same reason. This report describes a novel technique for the fabrication of a custom attachment to retain prosthesis. An acrylic resin removable partial denture (RPD) is retained by a custom attachment. The patrix part of the custom attachment is fabricated using molar bands, prefabricated circumferential clasp, and straight die pins. The matrix part of the attachment is constituted by the plastic sleeves of the straight die pins, which are embedded inside the tissue-fitting surface of the prosthesis. This article describes an inexpensive custom attachment for rehabilitating the long-span Kennedy class IV situation. The entire technique is reversible, inexpensive, and demands less skill compared to semi-precision and precision attachments. PMID:27134433

  15. Impact of mandibular implant prostheses on the oral health-related quality of life in partially and completely edentulous patients.

    PubMed

    Yunus, Norsiah; Masood, Mohd; Saub, Roslan; Al-Hashedi, Ashwaq Ali; Taiyeb Ali, Tara Bai; Thomason, John Mark

    2016-07-01

    To assess the oral health-related quality of life (OHRQoL) of patients provided with mandibular implant fixed partial prostheses (IFPP) for rehabilitation of two adjacent missing posterior teeth and complete denture patients provided with mandibular implant-supported overdenture (ISOD). The response to change in OHRQoL with implant prostheses was additionally compared. In this prospective study, 20 IFPP (mean age 47.0; SD 12.9 years) and 28 ISOD (mean age 61.5; SD 9.1 years) patients received 2 mandibular implants. Metal ceramic nonsplinted fixed prostheses were provided in IFPP group, while in ISOD group, the mandibular overdentures were retained by nonsplinted attachments. Patients rated their oral health-related quality of life using OHIP-14 Malaysian version at baseline (T0), 2-3 months (T1) and 1 year (T2) postimplant treatment. Mean OHIP-14 for total and domain scores between groups and intervals was analysed using repeated-measures ANOVA and t-test. Mann-Whitney and Wilcoxon signed-rank tests were used for the comparison of mean score change and effect size, while the association between pre- and post-treatment scores was determined using multivariate linear regression modelling. The total OHIP and domain scores before implant treatment were significantly higher (lower OHRQoL) in IFPP than in ISOD groups, except for physical pain where this domain showed similar impact in both groups. Postimplant scores between groups at T1 and T2 showed no significant difference. The mean score changes at T0-T1 and T0-T2 for total OHIP-14 and domains were significantly greater in IFPP except in the domains of physical pain and disability which showed no difference. Large effect size (ES) was observed for total OHIP-14 in IFPP while moderate in ISOD. Improved OHRQoL was dependent on the treatment group and pretreatment score. Improvement in OHRQoL occurred following both mandibular implant-supported overdentures and implant fixed partial prostheses. © 2015 John Wiley

  16. Managing the maxillary partially edentulous patient with extensive anterior tooth loss and advanced periodontal disease using a removable partial denture: a clinical report.

    PubMed

    Ma, Polly S; Brudvik, James S

    2008-10-01

    The treatment modality, a continuous occlusal rest removable partial denture, not only restored missing teeth but also stabilized the remaining dentition in a patient with advanced periodontal attachment loss. By engaging the guiding planes at the mesial surfaces of the abutments anteriorly and also the distal surfaces of the abutments posteriorly, the remaining teeth, with varying amounts of mobility, were splinted together by the framework. This conservative treatment option allows flexibility for easy repair during the life span of the prosthesis.

  17. [Progress in research and application of the edentulous custom trays].

    PubMed

    Sun, Y C; Jin, E L; Zhao, T; Wang, Y; Ye, H Q; Zhou, Y S

    2016-11-09

    Well designed and fabricated custom tray is the precondition to acquire qualified edentulous impression and key to successful complete denture. It has shown that primary impression without custom trays is hard to meet clinical requirements for successful restoration of complete denture. According to the fabrication techniques, edentulous custom tray can be classified into several types such as: compound trimming technique, handcrafted technique with polymerizing acrylic resin based on the study cast, and computer aided design and three dimensional printing(CAD & 3DP) technique based on the primary impression or study cast, etc. With regard to some special edentulous jaws, the custom tray and impression techniques such as open-window, frame cut, closed-mouth custom trays, and so on can be applied to acquire accurate impressions. All above technologies have their own characteristics and emphases. In clinic, appropriate custom trays should be selected according to residual ridge condition, oral status, and other clinical requirements of each edentulous patient.

  18. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 2: two case studies represent the fixed, respectively the combined fixed-removable prosthetic restoration by utilization of implants].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    The prosthetic rehabilitation of two partially edentulous patients is presented: one Patient was restored by permanent crowns and bridges attached to natural teeth and to implants, the second was treated by crowns attached to natural teeth and removable implant- supported prostheses. Depending on esthetic requirements and the localization of preparation margins all- or metal-ceramics were used for single crowns, metal-ceramics was used for bridges. In general, a well coordinated cooperation of dentist, surgeon and dental technician in treatment planning and realization is required for a successful prosthetic rehabilitation.

  19. A retrospective evaluation of the survival rates of splinted and non-splinted short dental implants in posterior partially edentulous jaws.

    PubMed

    Mendonça, Jose Alfredo; Francischone, Carlos Eduardo; Senna, Plinio Mendes; Matos de Oliveira, Ana Elisa; Sotto-Maior, Bruno Salles

    2014-06-01

    The aim of the present study is to evaluate the survival rate and bone loss around short implants (≤10 mm) supporting splinted or non-splinted posterior prostheses during a follow-up period of 3 to 16 years. A total of 453 implants from 198 patients was divided into splinted or non-splinted groups. Implant survival rate was calculated for each group, and potential risk was represented as odds ratio (OR). The final linear distance from implant platform level to the first bone-to-implant contact was compared to this same reference just after loading by digital periapical radiographs to determine the marginal bone loss (BL). The splinted group comprised 219 implants in 86 patients, whereas the non-splinted group included 234 implants from 112 patients. The mean follow-up period was 9.7 ± 3.7 years. Although different success rates were found for splinted (97.7%) and non-splinted (93.2%) groups, they exhibited similar BL (1.22 ± 0.95 mm and 1.27 ± 1.15 mm, respectively). The success of splinted implants was associated with no other variable, whereas non-splinted implants exhibited higher risk of failure when placed in men (OR = 3.2) and when implants shorter than 10 mm were used (OR = 3.6 and 4.1 for 8.5 mm and 7 mm, respectively). Regardless of group, 71.4% of the unsuccessful implants failed before the end of the first year after loading. Non-splinted posterior short implants had a somewhat lower success rate than splinted short implants, and the failure rate in non-splinted short implants appeared to be greater in males as well as in implants ≤10 mm.

  20. Retrospective cohort clinical investigation of a dental implant with a narrow diameter and short length for the partial rehabilitation of extremely atrophic jaws.

    PubMed

    Maló, Paulo S; de Araújo Nobre, Miguel A; Lopes, Armando V; Ferro, Ana S

    2017-01-01

    We investigated the short-term clinical outcomes of narrow-diameter short-length implants for the fixed-prosthetic partial rehabilitation of extremely resorbed jaws. Twenty-three patients requiring partial rehabilitations with narrow-platform short-length implants in any jaw were included in this study. In total, 30 implants 3.3 mm in diameter and 7 (n = 15 implants) or 8.5 (n = 15 implants) mm in length were inserted. The primary outcome measure was implant cumulative survival rate (CSR); the secondary outcome measures were marginal bone resorption at 1 and 3 years and the incidence of biologic and mechanical complications. Five patients (21.7%) with six implants (20%) were lost to follow-up. Two implants failed in two patients, yielding a CSR at 3 years of follow-up of 93.4%. The average (standard deviation) marginal bone resorption was 1.34 mm (0.95 mm) after the first year and 1.38 mm (0.78 mm) after the third year. Biologic complications occurred in three patients; mechanical complications occurred in three patients. Despite the limitations of the study, our findings show that the use of new narrow-diameter short-length implants for the rehabilitation of extremely atrophic regions is viable in the short-term, and can be considered a treatment alternative in extremely resorbed jaws.

  1. Improved Prefrontal Activity and Chewing Performance as Function of Wearing Denture in Partially Edentulous Elderly Individuals: Functional Near-Infrared Spectroscopy Study

    PubMed Central

    Kamiya, Kazunobu; Narita, Noriyuki; Iwaki, Sunao

    2016-01-01

    The purpose of this study was to elucidate the effects of wearing a denture on prefrontal activity during chewing performance. We specifically examined that activity in 12 elderly edentulous subjects [63.1±6.1 years old (mean ± SD)] and 12 young healthy controls (22.1±2.3 years old) using functional near-infrared spectroscopy (fNIRS) in order to evaluate the quality of prefrontal functionality during chewing performance under the conditions of wearing a denture and tooth loss, and then compared the findings with those of young healthy controls. fNIRS and electromyography were used simultaneously to detect prefrontal and masticatory muscle activities during chewing, while occlusal force and masticatory score were also examined by use of a food intake questionnaire. A significant increase in prefrontal activity was observed during chewing while wearing a denture, which was accompanied by increased masticatory muscle activity, occlusal force, and masticatory score, as compared with the tooth loss condition. Prefrontal activation during chewing while wearing a denture in the elderly subjects was not much different from that in the young controls. In contrast, tooth loss in the elderly group resulted in marked prefrontal deactivation, accompanied by decreased masticatory muscle activity, occlusal force, and masticatory score, as compared with the young controls. We concluded that intrinsic prefrontal activation during chewing with a denture may prevent prefrontal depression induced by tooth loss in elderly edentulous patients. PMID:27362255

  2. Applications of biomaterials for bone augmentation of jaws: clinical outcomes and in vitro studies

    PubMed Central

    TETTAMANTI, L.; BASSI, M. ANDREASI; TRAPELLA, G.; CANDOTTO, V.; TAGLIABUE, A.

    2017-01-01

    SUMMARY Partially or totally edentulous jaws frequently undergoes from moderate to severe bone atrophy with problems of prosthetic rehabilitation. The inability to make a prosthetic rehabilitation on implants may led to the use of a partial or total removable denture with difficulties in eating and speech, ulcerations of the oral mucosa and loss of facial vertical dimension. These problems may be solved performing bone augmentation procedures. Bone grafts and distraction osteogenesis brought implant dentistry from an experimental practice to become a consolidate dental procedure. Bone grafts, in particular, are currently a valuable treatment modality for the prosthetic rehabilitation. Numerous biomaterials have been developed for the rehabilitation of partially or totally edentulous jaws with fixed or removable dentures. The aim of this paper is to describe biomaterials for bone augmentation. Biomaterials are gradually resorbed by the osteoclasts and replaced by new bone formed through osteoblastic activity. Many biomaterials have been studied, but the most common are as follows: Allogro®, Algipore®, Osteobiol®, Peptide-15, Engipore®, Medpore®, Osteoplant®, Calcium sulfate, Perioglass®, Bio-Oss®, Calcium phosphate. PMID:28757934

  3. Multidisciplinary Approach in the Management of a Complex Case: Implant-Prosthetic Rehabilitation of a Periodontal Smoking Patient with Partial Edentulism, Malocclusion, and Aesthetic Diseases.

    PubMed

    Lanza, Alessandro; Di Francesco, Fabrizio; De Marco, Gennaro; Scognamiglio, Fabio; Aruta, Valeria; Itro, Angelo

    2017-01-01

    Complex periprosthetic cases are considered as challenges by clinicians. Clinical and radiographic parameters should be considered separately to make the right choice between an endodontically or periodontally compromised treated tooth and implant. Therefore, in order to decide whether the tooth is safe or not, data that have to be collected are specific parameters of both the patient and the clinician. In addition, the presence of periodontal, prosthetic, and orthodontic diseases requires patients to be set in multidisciplinary approach. The aim of this case report is to describe how the multidisciplinary approach could be the best way to manage difficult cases of implant-prosthetic rehabilitation. How to rehabilitate with fixed prosthesis on natural teeth and dental implants a smoker patient who presents with active periodontitis, multiple edentulous areas, dental malocclusion, and severe aesthetic problems was also described.

  4. Multidisciplinary Approach in the Management of a Complex Case: Implant-Prosthetic Rehabilitation of a Periodontal Smoking Patient with Partial Edentulism, Malocclusion, and Aesthetic Diseases

    PubMed Central

    Di Francesco, Fabrizio; De Marco, Gennaro; Scognamiglio, Fabio; Aruta, Valeria; Itro, Angelo

    2017-01-01

    Complex periprosthetic cases are considered as challenges by clinicians. Clinical and radiographic parameters should be considered separately to make the right choice between an endodontically or periodontally compromised treated tooth and implant. Therefore, in order to decide whether the tooth is safe or not, data that have to be collected are specific parameters of both the patient and the clinician. In addition, the presence of periodontal, prosthetic, and orthodontic diseases requires patients to be set in multidisciplinary approach. The aim of this case report is to describe how the multidisciplinary approach could be the best way to manage difficult cases of implant-prosthetic rehabilitation. How to rehabilitate with fixed prosthesis on natural teeth and dental implants a smoker patient who presents with active periodontitis, multiple edentulous areas, dental malocclusion, and severe aesthetic problems was also described. PMID:28421148

  5. 10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients.

    PubMed

    van Velzen, Frank J J; Ofec, Ronen; Schulten, Engelbert A J M; Ten Bruggenkate, Christiaan M

    2015-10-01

    This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients. Patients who had dental implant surgery in the period between November 1997 and June 2001, with a follow-up of at least 10 years, were investigated for clinical and radiological examination. Among the 506 inserted dental implants in 250 patients, 10-year data regarding the outcome of implants were available for 374 dental implants in 177 patients. In the current study, peri-implantitis was defined as advanced bone loss (≧1.5 mm. postloading) in combination with bleeding on probing. At 10-year follow-up, only one implant was lost (0.3%) 2 months after implant surgery due to insufficient osseointegration. The average bone loss at 10 year postloading was 0.52 mm. Advanced bone loss at 10-year follow-up was present in 35 dental implants (9.8%). Seven percent of the observed dental implants showed bleeding on probing in combination with advanced bone loss and 4.2% when setting the threshold for advanced bone loss at 2.0 mm. Advanced bone loss without bleeding on probing was present in 2.8% of all implants. In this prospective study, the 10-year survival rate at implant and patient level was 99.7% and 99.4%, respectively. Peri-implantitis was present in 7% of the observed dental implants according to the above-mentioned definition of peri-implantitis. This study shows that SLA implants offer predictable long-term results as support in the treatment of fully and partially edentulous patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Conventional prosthodontic management of partial edentulism with a resilient attachment-retained overdenture in a patient with a cleft lip and palate: a clinical report.

    PubMed

    Acharya, Varun; Brecht, Lawrence E

    2014-08-01

    Recent advances in surgery and orthodontics have resulted in improvements in the management of patients with a cleft lip or palate. Early surgical intervention and bone-grafting procedures have frequently been used to ensure closure of the cleft and continuity of the alveolar bone. However, a need for the prosthodontic management of patients with a cleft palate still exists. Most frequently, the indication is to restore the edentulous spaces located anteriorly in the vicinity of the residual cleft defect. In addition to improving the esthetic outcome, prosthodontic management also is required to restore function, especially occlusion and speech. This clinical report illustrates the management of an adult patient with a unilateral cleft of the lip and palate who required prosthodontic rehabilitation after surgery. The patient had previously undergone multiple surgeries and did not want to consider implant therapy as a treatment option. Thus, the patient was managed with fixed and removable prosthodontics with a maxillary overdenture prosthesis retained by microextracoronal resilient attachments, which were laser welded onto crowns on abutment teeth to obtain a functionally and esthetically acceptable result.

  7. Rehabilitation of postrior atrophic edentulous jaws: prostheses supported by 5 mm short implants or by longer implants in augmented bone? One-year results from a pilot randomised clinical trial.

    PubMed

    Esposito, Marco; Pellegrino, Gerardo; Pistilli, Roberto; Felice, Pietro

    2011-01-01

    To evaluate whether 5 mm short dental implants could be an alternative to augmentation with anorganic bovine bone and placement of at least 10 mm long implants in posterior atrophic jaws. Fifteen patients with bilateral atrophic mandibles (5-7 mm bone height above the mandibular canal), and 15 patients with bilateral atrophic maxillae (4-6 mm bone height below the maxillary sinus) and bone thickness of at least 8 mm, were randomised according to a splitmouth design to receive one to three 5 mm short implants or at least 10 mm long implants in augmented bone. Mandibles were vertically augmented with interpositional bone blocks and maxillary sinuses with particulated bone via a lateral window. Implants were placed after 4 months, submerged and loaded, after 4 months, with provisional prostheses. Four months later, definitive provisionally cemented prostheses were delivered. Outcome measures were: prosthesis and implant failures, any complication and peri-implant marginal bone level changes. In 5 augmented mandibles, the planned 10 mm long implants could not be placed and shorter implants (7 and 8.5 mm) had to be used instead. One year after loading no patient dropped out. Two long (8.5 mm in the mandible and 13 mm in the maxilla) implants and one 5 mm short maxillary implant failed. There were no statistically significant differences in failures or complications. Patients with short implants lost on average 1 mm of peri-implant bone and patients with longer implants lost 1.2 mm. This difference was statistically significant. This pilot study suggests that 1 year after loading, 5 mm short implants achieve similar if not better results than longer implants placed in augmented bone. Short implants might be a preferable choice to bone augmentation since the treatment is faster, cheaper and associated with less morbidity, however their long-term prognosis is unknown.

  8. Three-year results from a randomised controlled trial comparing prostheses supported by 5-mm long implants or by longer implants in augmented bone in posterior atrophic edentulous jaws.

    PubMed

    Esposito, Marco; Pistilli, Roberto; Barausse, Carlo; Felice, Pietro

    2014-01-01

    To evaluate whether 5-mm short dental implants could be an alternative to augmentation with anorganic bovine bone and placement of at least 10-mm long implants in posterior atrophic jaws. Fifteen patients with bilateral atrophic mandibles (5 mm to 7 mm bone height above the mandibular canal) and 15 patients with bilateral atrophic maxillae (4 mm to 6 mm bone height below the maxillary sinus), and bone thickness of at least 8 mm, were randomised according to a split-mouth design to receive one to three 5-mm short implants or at least 10-mm long implants in augmented bone. Mandibles were vertically augmented with interpositional bone blocks and maxillary sinuses with particulated bone via a lateral window. Implants were placed after 4 months, submerged and loaded, after another 4 months, with provisional prostheses. Four months later, definitive provisionally cemented prostheses were delivered. Outcome measures were: prosthesis and implant failures; any complication and peri-implant marginal bone level changes. In five augmented mandibles, the planned 10-mm long implants could not be placed and shorter implants (7 mm and 8.5 mm) had to be used instead. Three years after loading, two patients, one treated in the mandible and one in the maxilla, dropped out. Three prostheses (1 mandibular and 2 maxillary) failed in the short implant group versus none in the long implant group. In mandibles, one long implant failed versus two short implants in 1 patient. In maxillae, one long implant failed versus three short implants in 2 patients. There were no statistically significant differences in the failures. Eight patients had 13 complications at short implants (1 patient accounted for 6 complications) and 11 patients had 13 complications at long implants. There were no statistically significant differences in complications (P = 0.63, difference = 0.10, 95% CI from -0.22 to 0.42). Three years after loading, patients with mandibular implants lost on average 1.44 mm at short

  9. Jaw bite force measurement device.

    PubMed

    Flanagan, Dennis; Ilies, Horea; O'Brien, Brendan; McManus, Anne; Larrow, Beau

    2012-08-01

    We describe a cost-effective device that uses an off-the-shelf force transducer to measure patient bite force as a diagnostic aid in determining dental implant size, number of implants, and prosthetic design for restoring partial edentulism. The main advantages of the device are its accuracy, simplicity, modularity, ease of manufacturing, and low cost.

  10. Management of Edentulous Orofacial Dyskinesia.

    PubMed

    Singh, Bishnupati; Sinha, Namrata; Giri, Tapan; Chethan, M D; Mahadevan, Vallabh; Tamrakar, Amit

    2015-07-01

    Edentulous orofacial dyskinesia is a rare condition, characterized by involuntary rhythmic movements of the mandible and presents an embarrassing situation for the patient. Edentulism has been considered as one of the proponents of these irregular movements, and rehabilitation of these patients with complete denture-fabrication using traditional technique restores the masticatory inefficiency and the esthetic component of the patient. Surprisingly, these movements disappear during the clinical steps of complete denture-fabrication and upon insertion of the dentures. Disturbances in the proprioception following loss of tooth may be a contributory factor for edentulous dyskinesia.

  11. Three-year treatment outcomes with three brands of implants placed in the posterior maxilla and mandible of partially edentulous patients.

    PubMed

    Ozkan, Yasar; Ozcan, Mutlu; Akoglu, Burcin; Ucankale, Mert; Kulak-Ozkan, Yasemin

    2007-02-01

    Survival rates of implants in posterior regions vary among clinical studies. Problems occur more often in the posterior segment of the maxilla due to proximity of the maxillary sinus and reduced quality or quantity of alveolar bone. This clinical study evaluated the treatment outcomes of 3 brands of implants in the posterior maxillae and mandibles of 63 patients. Treatment outcomes of all implants were assessed according to implant type, location, patient gender, periodontal status, and prosthesis type. A total of 203 implants-105 ITI (ITI), 53 Camlog (CAM), and 45 Frialit (FRI)-were placed in 63 patients (38 women, 25 men). One hundred twelve implants were located in the posterior mandible and 91 in the posterior maxilla. All implants were longer than 10 mm and had a diameter larger than 3.5 mm. Implants in the ITI group were placed in a 1-stage surgery. The CAM and FRI groups were treated with a 2-stage surgical protocol. Implants were not loaded until osseointegration was complete, which was determined clinically and radiographically. At that point, implants were restored with 50 single crowns and 81 fixed partial dentures (FPDs). While 11 FPDs connected implants to natural teeth, 70 FPDs were supported by implants only. Standardized radiographs were made, and clinical parameters were recorded at prosthesis insertion (baseline) and at each recall evaluation (6, 12, 24, and 36 months). Plaque index (PI), sulcus bleeding index (SBI), peri-implant probing depth (PD), and radiographic marginal bone loss (MBL) levels were recorded at baseline, along with any biological and mechanical complications. Repeated-measures ANOVA, Kruskal-Wallis test, Wilcoxon signed rank test, and paired samples tests were used for statistical analysis (alpha=.05). One implant was lost during the osseointegration period in 1 woman due to infection. The cumulative implant treatment outcome was 99.3%. At the 3-year recall, plaque accumulation was significantly higher than baseline scores (P

  12. Three-year post-loading results of a randomised, controlled, split-mouth trial comparing implants with different prosthetic interfaces and design in partially posterior edentulous mandibles.

    PubMed

    Pozzi, Alessandro; Tallarico, Marco; Moy, Peter K

    2014-01-01

    To compare the clinical and radiological outcomes of two implant designs with different prosthetic interfaces and neck configurations. Thirty-four partially edentate patients randomly received at least one NobelActive implant (Nobel Biocare, Göteborg, Sweden) with back-tapered collar, internal conical connection and platform shifting design, and one NobelSpeedy implant (Nobel Biocare) with external hexagon and flat-to-flat implant-abutment interface according to a split-mouth design. Follow-up continued to 3 years post-loading. The primary outcome measures were the success rates of the implants and prostheses, and the occurrence of any surgical and prosthetic complications during the entire follow-up. Secondary outcome measures were: horizontal and vertical peri-implant marginal bone level (MBL) changes, resonance frequency analysis values at implant placement and loading (4 months), sulcus bleeding index (SBI) and plaque score (PS). No drop-out occurred. No implants and prostheses failures were observed to the 3-year follow-up. MBL changes were statistically significant different with better results for the NobelActive implants for both horizontal and vertical measurements (P = 0.000). After 3 years post-loading, the NobelActive implants underwent a mean vertical bone resorption of 0.66 mm, compared with 1.25 mm for the NobelSpeedy Groovy implants (P = 0.000); the mean horizontal bone resorption was 0.19 mm for the NobelActive implants and 0.60 mm for the NobelSpeedy Groovy implants (P = 0.000). A high ISQ value was found for both implants, and no statistically significant difference was found for ISQ mean values between interventions (P = 0.941 at baseline; P = 0.454 at implantabutment connection; P = 0.120 at prosthesis delivery). All implants showed good periodontal health at the 3-year-in-function visit, with no significant differences between groups. The results of this research suggest that in well-maintained patients, the MBL changes could be affected by

  13. Bone tissue in different parts of the edentulous maxilla and mandible.

    PubMed

    Lindhe, Jan; Bressan, Eriberto; Cecchinato, Denis; Corrá, Enrico; Toia, Marco; Liljenberg, Birgitta

    2013-04-01

    The composition of the fully healed edentulous ridge of the posterior maxilla was recently examined and was found to contain about 50% mineralized bone and 16% bone marrow. The objective was to examine the composition of the tissue of the fully healed ridge in different portions of the maxilla and the mandible in partially dentate subjects. Eighty-seven healthy subjects were included. A trephine drill was used to harvest hard tissue specimens. The biopsies were decalcified, embedded in paraffin, sectioned, stained, and examined using a point-counting procedure. The marginal portion of the jaws almost consistently contained a cortical cap that was significantly wider in the mandible than in the maxilla and twice as wide in the anterior as in the posterior segments of the mandible. Lamellar bone and bone marrow were the dominating tissue elements. Lamellar bone occupied about 63% of the tissue in the mandible and 46% in the maxilla. The maxilla contained about 23% bone marrow as compared to 16% in the mandible. In the mandible, 70% (anterior) and 57% (posterior) were made up of lamellar bone. In the maxilla, the proportion of lamellar bone in the anterior and posterior segments was similar (about 45%). Bone marrow occupied close to 40% of the anterior maxilla, while in the posterior maxilla and the anterior and posterior mandible marrow comprised between 13 and 18%. Marked differences existed with respect to tissue composition of the edentulous ridge between the maxilla and the mandible. The cortical crest was wider in the mandible than in the maxilla, and widest in the symphysis region of the mandible. The proportion of bone marrow was greater in the maxilla than in the mandible. The maxillary front tooth region was poor in lamellar bone but rich in bone marrow, while the anterior mandible contained large amounts of mineralized bone but small amounts of bone marrow. © 2012 John Wiley & Sons A/S.

  14. Individual- and community-level social gradients of edentulousness.

    PubMed

    Ito, Kanade; Aida, Jun; Yamamoto, Tatsuo; Ohtsuka, Rika; Nakade, Miyo; Suzuki, Kayo; Kondo, Katsunori; Osaka, Ken

    2015-03-11

    Community-level factors as well as individual-level factors affect individual health. To date, no studies have examined the association between community-level social gradient and edentulousness. The aim of this study was to investigate individual- and community-level social inequalities in edentulousness and to determine any explanatory factors in this association. We analyzed the data from the Japan Gerontological Evaluation Study (JAGES). In 2010-2012, 112,123 subjects aged 65 or older responded to the questionnaire survey (response rate = 66.3%). Multilevel logistic regression analysis was applied to determine the association between community-level income and edentulousness after accounting for individual-level income and demographic covariates. Then, we estimated the probability of edentulousness by individual- and community-level incomes after adjusted for covariates. Of 79,563 valid participants, the prevalence of edentulousness among 39,550 men (49.7%) and 40,013 women (50.3%) were both 13.8%. Living in communities with higher mean incomes and having higher individual-level incomes were significantly associated with a lower risk of edentulousness (odds ratios [ORs] by 10,000 USD increments were 0.37 (95% confidence interval [CI] [0.22-0.63]) for community-level and 0.85 (95% CI [0.84-0.86]) for individual-level income). Individual- and community-level social factors, including density of dental clinics, partially explained the social gradients. However, in the fully adjusted model, both community- and individual-level social gradients of edentulousness remained significant (ORs = 0.43 (95% CI [0.27-0.67]) and 0.90 (95% CI [0.88-0.91]), respectively). One standard deviation changes in community- and individual-level incomes were associated with 0.78 and 0.84 times lower odds of edentulousness, respectively. In addition, compared to men, women living in communities with higher average incomes had a significantly lower risk of edentulousness (p-value for

  15. An introduction to the 'Mennen plate' and its use in treatment of fractures of the edentulous mandible.

    PubMed

    Maung Aung, T; Brook, I M; Crofts, C E; Trowbridge, E A

    1990-08-01

    A paraskeletal clamp plate (Mennen) offers a novel method of fixation for mandibular fractures. Its application is relatively atraumatic and this together with the minimal disruption to the local blood supply may make this clamp particularly suited to fixation of fractures of the atrophic edentulous jaw. Its use in six such cases is reported.

  16. Alveolar ridge atrophy related to facial morphology in edentulous patients

    PubMed Central

    Kuć, Joanna; Sierpińska, Teresa; Gołębiewska, Maria

    2017-01-01

    Objectives The morphology of the alveolar process determines the retention and stability of prosthetic restorations, thereby determining the result of the therapy. Considering that the edentulous jaws may be affected by the atrophy process, it was hypothesized that the morphology of the alveolar process of the maxilla may be dependent on the anterior facial height and anatomy of the mandible. Subjects and methods Twenty-five healthy edentulous Caucasian individuals were randomly chosen. Each subject underwent a lateral cephalogram before and after prosthetic rehabilitation. During exposition, newly made prostheses were placed in the patient’s mouth. Teeth remained in maximal intercuspidation. Morphological parameters were evaluated according to the Ricketts, McNamara, and Tallgren’s method. Results An inversely proportional association was observed between patient age and the distal part of the maxilla. A statistically significant connection was noted between the vertical dimension of alveolar ridge and anterior total and lower facial height conditioned by prosthetic rehabilitation. Conclusion The height of the lateral part of the alveolar ridge of the maxilla remains in connection with the anterior total and lower facial height obtained in the course of prosthetic rehabilitation. The vertical dimension of the alveolar ridge of the maxilla seems to be in close relationship with the morphology of the lower jaw.

  17. Socio-demographic factors and edentulism: the Nigerian experience

    PubMed Central

    Esan, Temitope Ayodeji; Olusile, Adeyemi Oluniyi; Akeredolu, Patricia Adetokunbo; Esan, Ayodeji Omobolanle

    2004-01-01

    Background The rate of total edentulism is said to be increasing in developing countries and this had been attributed mainly to the high prevalence of periodontal diseases and caries. Several reports have shown that non-disease factors such as attitude, behavior, dental attendance, characteristics of health care systems and socio-demographic factors play important roles in the aetiopathogenesis of edentulism. The aim of this study was to assess the relationship between socio-demographic factors and edentulism. Methods A total of 152 patients made up of 80 (52.6%) males and 72 (47.4%) females who presented in two prosthetic clinics located in an urban and a rural area were included in the study. The relationship between gender, age, socio-economic status and edentulism in this study population was established. Results No significant relationship between gender and denture demand was noted in the study. The demand for complete dentures increased with age while the demand for removable partial dentures also increased with age until the 3rd decade and then started to decline. A significant relationship was found between denture demand and the level of education with a higher demand in lower educational groups (p < 0.001). In addition, the lower socio-economic group had a higher demand more for prostheses than the higher group. Conclusions The findings in this study revealed a significant relationship between socio-demographic variables and edentulism with age, educational level and socio-economic status playing vital roles in edentulism and denture demand. PMID:15555072

  18. Symposium on semiprecision attachments in removable partial dentures. Occlusal relationships.

    PubMed

    Whitbeck, P; Ivanhoe, J R

    1985-01-01

    This article discusses current concepts of occlusion and describes the methods of creating a physiologic occlusion for the partially edentulous patient. Specific recommendations are made for choices of materials, techniques, and occlusal schemes for various edentulous situations.

  19. Jaw Injuries and Disorders

    MedlinePlus

    ... Jaw problems include Fractures Dislocations Temporomandibular joint dysfunction Osteonecrosis, which happens when your bones lose their blood supply Cancers Treatment of jaw problems depends on the cause.

  20. [The atrophic jaw from the dental surgeon's point of view].

    PubMed

    Obwegeser, H

    1977-09-01

    A report on 3000 cases of jaw atrophy over a period of 20 years. These cases underwent surgery and the results were obtained on the basis of close collaboration between maxillofacial surgery and prosthetics. Certain deductions could be obtained from these numerous patients over a longe period of observation. It is now possible to separate wistful thinking from reality. Subperiosteal implants have, in spite of chronic infections, functioned over a period of 10 years and more. Enossal implants seem to do the same for partial prosthetics. Complete failure of either form of implant is to be expected in edentulous mouths. Loss of a subperiosteal or enossal implant generally leaves a condition requiring new surgical intervention. The methods of vestibuloplasty, tuberoplasty and lowering of the floor of the mouth have been generally successful, if proper indication, surgical technique and prosthetic rehabilitation are observed by competent professionals. In plastic surgery of the alveolar process the use of ribs has been successful in this clinic. Even though postoperative resorption may destroy 50% and more of the obtained height of the alveolar process, the results justify this kind of surgery. The obtained results suggest that the methods described have justified their due place in maxillofacial surgery, because they may be considered to be results at long term.

  1. Muscular activity may improve in edentulous patients after implant treatment.

    PubMed

    Afrashtehfar, Kelvin I; Schimmel, Martin

    2016-12-01

    Data sourcesMedline via Pubmed and the Cochrane Library were searched from January 1980 to September 2013. This was complemented by a manual search of the magazines Deutsche Zahnaerztliche Zeitung, Quintessenz, Zeitschrift für Zahnärztliche Implantologie, Schweizerische Monatszeitschrift and Implantologie. Additionally, the list of reference s of all selected full-text articles and related reviews were further scrutinised for potential included studies in English or German.Study selectionThree review authors independently searched for clinical trials that assessed the muscular activity in the intervention groups: edentulous patients treated with implant-overdentures (IODs) and implant-supported fixed dental prostheses (ISFDPs) and the comparison groups: dentates and edentulous patients treated with mucosa-borne complete removable dental prostheses (CRDPs).Data extraction and synthesisThe primary outcome was the muscular activity (measured by electromyography [EMG]) in masseter or temporalis muscle of the participants during clenching and chewing. The data extraction of each included study consisted of author, year, age range, treatment, number of participants, number of implants inserted, arch treated, opposite jaw, kind and side of the muscles that were measured. EMG gain or loss (unit measured: volt) was considered by using the effect size. For the meta-analyses only the studies that included masseter muscle measured separately from temporalis were considered. Concerning the side of measurement (right and left side measured together or right and left side measured separately), only the dominant type in each category was included.ResultsSixteen articles, out of the initial 646 retrieved abstracts, were analysed. The muscular activity of edentulous subjects increased after implant support therapy during clenching (effect size [ES]: 2.18 [95% confidence interval [CI]: 1.14, 3.23]) and during chewing (ES: 1.45 [95 % CI: 1.21, 1.69]). In addition, the pooled EMG

  2. Maxillo Mandibular Fixation in Edentulous Scenarios: Combined MMF Screws and Gunning Splints.

    PubMed

    Chaudhary, Zainab; Sharma, Rakesh; Krishnan, Sriram

    2014-06-01

    A fracture of the maxillary or mandibular bone requires the afflicted to undergo a maxillo mandibular fixation for the establishment of pre traumatic occlusion. This process is quiet tedious and consumes a considerable period of time before any surgical procedure can commence. Such a situation can be complicated in case the individual with maxillomandibular fracture has sparse or absent dentition; for such cases a splint is fabricated or an erstwhile existing denture is used for maintaining a vertical jaw proportion. Stabilizing such splints to the jaw requires various invasive approaches that can bring into harm's way, adjacent soft tissue vital structures. We describe here an innovative technique combining the time tested method of the "gunning splint" and the advanced minimally invasive MMF screws for obtaining closed reduction in edentulous jaw fractures.

  3. [Three-dimensional finite element analysis of stress distribution about abutments periodontal membranes of separated removable partial denture and conical telescope].

    PubMed

    Tang, Ying; Wang, Min; Luo, Yun; Man, Yi

    2009-10-01

    To investigate and compare the stress of edentulous mucosa and periodontal membranes of the abutments under vertical loads for separated removable partial denture or conical telescope denture. One patient who had lost the second premolar and the first molar on the upper jaw and had I mobile abutments was chosen in the study. Two precise three dimensional finite element models were constructed by using screw CT image reconstruction technique and Materialise Mimics, Pro/Engineer WF 2.0, ANSYS Workbench software. Vertical forces were loaded on the two models. Then comparing and analyzing the von Mises stress distribution of the edentulous mucosa and the periodontal membranes of abutments between the separate removable partial denture and conical telescope denture in the software of ANSYS Workbench. The von Mises stress values of the edentulous mucosa of separate removable partial denture were larger than that of the conical telescope denture. The von Mises stress values of abutments periodontal membranes of separate removable partial denture were lower than that of conical telescope denture. Under vertical loads, compare with conical telescope denture, the separate removable partial denture can protect the abutments.

  4. The oral health-related quality of life in edentulous patients treated with conventional complete dentures.

    PubMed

    Albaker, Abdulaziz M

    2013-03-01

    To compare the oral health-related quality of life (OHRQoL) between patients with both maxillary and mandibular complete denture and those with either the maxillary or the mandibular complete denture. Satisfaction of denture wearers can be estimated using the OHRQoL questionnaires like the OHIP-EDENT and the Geriatric Oral Health Assessment Index (GOHAI). Two questionnaires were used to compare the OHRQoL between edentulous patients who had conventional removable complete denture on both jaws and those who had on either one of the jaws. The age of the participants ranged from 42 to 75 years, with the mean age of 58 ± 8.12 years. The mean OHIP-EDENT scores were significantly high among those who wore conventional dentures in both jaws (54.12 ± 5.21), compared with the participants who only had denture either on upper or lower jaw (46.52 ± 7.35). It was noticed that the mean GOHAI score was significantly lower (p < 0.05) among participants who had conventional denture on both upper and lower jaw (28.25 ± 3.67), as compared to those who had conventional denture only on one arch (35.12 ± 2.11). Patients with complete dentures in both jaw (Group I) were less satisfied than patients with single complete denture (Group II). The result obtained in this study shows dissatisfaction with conventional dentures among edentulous patients. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

  5. A Case of Bisphosphonate-Related Osteonecrosis of the Jaw in a Patient with Subpontic Osseous Hyperplasia

    PubMed Central

    Watanabe, Hiroshi; Nakayama, Hidenori; Goto, Mitsuo; Kurita, Kenichi

    2017-01-01

    Subpontic osseous hyperplasia (SOH) is a growth of bone occurring on the edentulous ridge beneath the pontics of fixed partial dentures (FPDs). This report describes a case of bisphosphonate- (BP-) related osteonecrosis of the jaw (BRONJ) in a SOH patient followed by deciduation of the bony lesion. A 73-year-old woman visited a dental clinic after experiencing pain and swelling beneath the pontics of a FPD that had been inserted 15 years ago. The pontics were removed, but the symptoms persisted and she was referred to our hospital. There was an osseous bulge and gum swelling around the edentulous ridge of teeth 18 and 19, as well as bone exposure. As she had been taking an oral BP for 6 years, we diagnosed this case as stage 2 BRONJ. Following BP withdrawal, the bony lesion detached from the mandible. The tissue was diagnosed as sequestrum based on the histopathological findings. Two months after deciduation, epithelialization over the area of exposed bone was achieved and no recurrence has been observed. PMID:28286679

  6. [Jaws of primitive mammals].

    PubMed

    Tsubamoto, Takehisa

    2005-06-01

    Some of main osteological differences between mammals and reptiles are seen in the number of bones that constitute lower jaw and in jaw articulation. A lower jaw of mammals consists of only one bone, while in reptiles it consists of several bones (e.g., four to six in lizards and five in crocodiles). The jaw articulation in mammals is performed by squamosal of the skull and the mandible ( = dentary), while in reptiles it is done by quadrate of the skull and articular of the lower jaw. When mammals first appeared about 200 million years ago in the Mesozoic Era, the jaws of primitive mammals were morphologically intermediate between those of reptiles and typical mammals. Here, I briefly introduce the evolution of lower jaw morphology from the reptilian one to the mammalian one, showing lower jaw features of some mammal-like reptiles and primitive mammals.

  7. Jaw and Order

    ERIC Educational Resources Information Center

    Mooshammer, Christine; Hoole, Philip; Geumann, Anja

    2007-01-01

    It is well-accepted that the jaw plays an active role in influencing vowel height. The general aim of the current study is to further investigate the extent to which the jaw is active in producing consonantal distinctions, with specific focus on coronal consonants. Therefore, tongue tip and jaw positions are compared for the German coronal…

  8. Aesthetic treatment option for completely edentulous patients using CAD/CAM technology.

    PubMed

    Kleinman, Alejandro; Avendano, Sergio; Leyva, Francisco

    2008-04-01

    In recent years, advancements have been made in CAD/CAM technology that have allowed for the development of different treatments regarding the rehabilitation of patients with natural dentition, as well as patients with dental implants. Contemporary systems can also allow prosthetic rehabilitation for partially and completely edentulous patients. This article describes a restorative alternative to fixed implant-supported reconstruction of completely edentulous patients, utilizing a CAD/CAM-generated framework and CAD/CAM-generated all-ceramic cement-retained crowns. In addition to delivering an optimally aesthetic restoration, this design permits a precise and passive prosthetic fit.

  9. Prevalence of signs of temporomandibular joint dysfunction in asymptomatic edentulous subjects: a cross-sectional study.

    PubMed

    Shetty, Rajesh

    2010-06-01

    Patients having complete dentures with reduced vertical dimension generally do not manifest Temporomandibular Joint problems. It is not understood as to why the closure of jaws in dentulous individuals can predispose to Temporomandibular Joint problems, while the same etiology in edentulous subjects does not cause any concern. This study was planned to find out the prevalence of various Temporomandibular Joint dysfunction signs in subjects who were edentulous for a period of 6 months to 2 year. The various signs were obtained from a population of 100 healthy asymptomatic edentulous subjects by a questionnaire and then were clinically examined for the presence or absence of signs of Temporomandibular Joint dysfunction. 59% of the subjects exhibited one or more signs of Temporomandibular Joint dysfunction, 41% of the subjects did not show any signs of Temporomandibular Joint dysfunction. 56.6% of males reported signs of Temporomandibular Joint dysfunction when compared with females which was 62.5%. 43.3% of males did not show any signs of Temporomandibular Joint dysfunction when compared with those of the females which was 37.5%. The number of subjects who showed two signs was 29%, subjects who had only one sign was 25%. It was found that dysfunction was prevalent among both men and women in more than half of the asymptomatic subjects examined. 59% had one or as many as three signs of Temporomandibular dysfunction. The most commonly seen Joint dysfunction was the joint sounds which was 47%

  10. [Application of one-piece implant-supported detachable telescope retained fixed bridge in edentulous cases].

    PubMed

    Wang, Qiao-na; Li, Ming; Qiu, Jing; Zhang, Xiao-zhen; Wu, Zi-qiang; Chen, Dong-lei; Xu, Jing-ming; Tang, Chun-bo

    2015-12-01

    To evaluate the clinical effectiveness of one-piece implant-supported detachable telescopic fixed bridge in edentulous patients. Seventeen patients were treated with one-piece implant-supported detachable telescopic fixed bridge. A total of 18 prostheses were fabricated with 8 in the upper jaws and 10 in the lower jaws.Fixed bridges retained by telescopic crowns were used as final prostheses, with milling titanium or all-ceramic abutments as primary crowns, gold-electroforming crowns as secondary crowns. Surveys about clinical and radiographic examination, satisfaction and prosthetic complications were conducted after 3 months,1 year, 2 years, 3 years after final rehabilitation. Data analysis was performed using SPSS 17.0 software package. Radiography showed stable bone levels for all implants except 2 implants, which were observed slight marginal bone resorption. The results of one-way ANOVA showed that no significant difference in modified plaque index or modified sulcus blooding index was found during the follow-up period (P>0.05). The probing attachment level deteriorated by 1.5 mm during the first 3 years (P<0.05). Eighteen restoration provided sufficient fixation and stability. Two porcelain fractures occured but had no influence on restoration. The patients were highly satisfied with the outcomes. The frequency of prosthetic maintenance per patient per year was 0.11. One-piece implant-supported detachable telescopic fixed bridge is an effective method with satisfactory long-term aesthetic and stable outcomes in edentulous patients.

  11. Digital Cephalometric Tracings by PRO-CEPH V3 Software for Comparative Analyses of Vertical Dimension in Edentulous Patients

    PubMed Central

    Chittaranjan, B.; Kumar, B. Arun; Taruna, M.; Kumar, M. Pavan; Reddy, M. Ramu

    2015-01-01

    Background Several methods, some physiological, some radiographical and some merely based on experience are taken upon by the practitioner to get him/her close to VDO in the edentulous patients. No single method can however claim to be the perfect answer. Lateral cephalograms have been a standard mode of determining the vertical dimensions in dentate and edentulous patients since the past. Due to unavoidable manual errors, there are chances of variations in the radiographic method too. Advancement in the digital technology has made recording jaw relations faster, simpler and more precise. Aim This study compared the vertical dimension of occlusion in edentulous patients recorded by using three different physiological methods with the aid of digital cephalometric tracings using indigenously developed PRO-CEPH V3 software. Materials and Methods For the present study a total of 50 dentulous and 25 edentulous patients were selected through inclusion and exclusion criteria. A lateral cephalometric radiograph was taken for all the 50 dentulous subjects at Maximum Intercuspation (VDO) whereas three lateral cephalometric radiographs were obtained for all edentulous patients at the VDO following three different techniques- the Niswonger’s method, Phonetics method and Swallowing threshold method. Cephalometric tracings were carried out using indigenously developed PRO-CEPH V3 software. Linear and angular measurement were made and analysed. Conclusion The indigenously developed software PRO-CEPH V3 is capable of making both the linear and angular measurement and therefore provide with relative credibility information regarding the possible VDO in the edentulous patients through cephalometric radiography. PMID:26155550

  12. Application of FDM three-dimensional printing technology in the digital manufacture of custom edentulous mandible trays

    PubMed Central

    Chen, Hu; Yang, Xu; Chen, Litong; Wang, Yong; Sun, Yuchun

    2016-01-01

    The objective was to establish and evaluate a method for manufacture of custom trays for edentulous jaws using computer aided design and fused deposition modeling (FDM) technologies. A digital method for design the custom trays for edentulous jaws was established. The tissue surface data of ten standard mandibular edentulous plaster models, which was used to design the digital custom tray in a reverse engineering software, were obtained using a 3D scanner. The designed tray was printed by a 3D FDM printing device. Another ten hand-made custom trays were produced as control. The 3-dimentional surface data of models and custom trays was scanned to evaluate the accuracy of reserved impression space, while the difference between digitally made trays and hand-made trays were analyzed. The digitally made custom trays achieved a good matching with the mandibular model, showing higher accuracy than the hand-made ones. There was no significant difference of the reserved space between different models and its matched digitally made trays. With 3D scanning, CAD and FDM technology, an efficient method of custom tray production was established, which achieved a high reproducibility and accuracy. PMID:26763620

  13. Application of FDM three-dimensional printing technology in the digital manufacture of custom edentulous mandible trays.

    PubMed

    Chen, Hu; Yang, Xu; Chen, Litong; Wang, Yong; Sun, Yuchun

    2016-01-14

    The objective was to establish and evaluate a method for manufacture of custom trays for edentulous jaws using computer aided design and fused deposition modeling (FDM) technologies. A digital method for design the custom trays for edentulous jaws was established. The tissue surface data of ten standard mandibular edentulous plaster models, which was used to design the digital custom tray in a reverse engineering software, were obtained using a 3D scanner. The designed tray was printed by a 3D FDM printing device. Another ten hand-made custom trays were produced as control. The 3-dimentional surface data of models and custom trays was scanned to evaluate the accuracy of reserved impression space, while the difference between digitally made trays and hand-made trays were analyzed. The digitally made custom trays achieved a good matching with the mandibular model, showing higher accuracy than the hand-made ones. There was no significant difference of the reserved space between different models and its matched digitally made trays. With 3D scanning, CAD and FDM technology, an efficient method of custom tray production was established, which achieved a high reproducibility and accuracy.

  14. Prosthetic rehabilitation of an edentulous patient with cleft palate.

    PubMed

    Sarmento, Hugo Ramalho; Rodigues, Polyana Barbara; Marcello-Machado, Raissa Micaella; Pinto, Luciana Rezende; Faot, Fernanda

    2014-01-01

    It is difficult today to find older patients without their cleft palate prosthetically rehabilitated. This case report presents the rehabilitation by conventional dental prostheses of a cleft palate patient who had no prior treatment. A 52-year-old male presented himself to have his fissured palate obturated and occlusion restored. He reported difficulties in swallowing food and liquids, along with a severe speech disability. The patient's medical history revealed diabetes mellitus type II, hypertension, low vision due to macular atrophic lesions, and xerostomia. The upper and lower arches were completely and partially edentulous, respectively. The treatment plan involved a conventional denture to be placed in the upper arch, and a removable partial denture to be placed in the lower arch.

  15. Biological Width around One- and Two-Piece Implants Retrieved from Human Jaws

    PubMed Central

    Judgar, Ricardo; Zenobio, Elton; Coelho, Paulo G.; Feres, Magda; Rodrigues, Jose A.; Mangano, Carlo; Iezzi, Giovanna; Piattelli, Adriano; Shibli, Jamil Awad

    2014-01-01

    Several histologic studies regarding peri-implant soft tissues and biological width around dental implants have been done in animals. However, these findings in human peri-implant soft tissues are very scarce. Therefore, the aim of this case series was to compare the biological width around unloaded one- and two-piece implants retrieved from human jaws. Eight partially edentulous patients received 2 test implants in the posterior mandible: one-piece (solid implants that comprise implant and abutment in one piece) and two-piece (external hexagon with a healing abutment) implants. After 4 months of healing, the implants and surrounding tissue were removed for histologic analysis. The retrieved implants showed healthy peri-implant bone and exhibited early stages of maturation. Marginal bone loss, gaps, and fibrous tissue were not present around retrieved specimens. The biologic width dimension ranged between 2.55 ± 0.16 and 3.26 ± 0.15 to one- and two-piece implants, respectively (P < 0.05). This difference was influenced by the connective tissue attachment, while sulcus depth and epithelial junction presented the same dimension for both groups (P > 0.05). Within the limits of this study, it could be shown that two-piece implants resulted in the thickening of the connective tissue attachment, resulting in the increase of the biological width, when compared to one-piece implants. PMID:25050375

  16. Oral conditions and aptitude to receive implants in patients with removable partial denture: a cross-sectional study. Part II Aptitude.

    PubMed

    Bassi, F; Schierano, G; Lorenzetti, M; Preti, G

    1996-03-01

    The aim of this study was to evaluate the possibility of replacing removable partial denture (RPD) with fixed partial dentures on osseointegrated implants in a selective group of patients with partially edentulous lower jaws. Forty patients were evaluated to receive implants. Twenty-three patients showed a precarious oral hygiene, five patients refused the treatment (being satisfied with their RPD), six refused for economic reasons, three patients refused for fear and scepticism, one for long duration of therapy, and one was not treated because of a very marked atrophy of the alveolar crest. Finally, one patient was treated with implants. For these reasons, at the present time implants are not an appropriate treatment for introduction into large-scale public health programmes and RPD must still be considered a valid therapeutic procedure.

  17. Jaw - broken or dislocated

    MedlinePlus

    ... This may be due to: Assault Industrial accident Motor vehicle accident Recreational or sports injury Trips and falls ... Hold the jaw gently in place with your hands on the way to the emergency room. You ...

  18. [Jaws of herbivorous mammals].

    PubMed

    Konishi, Shogo

    2005-08-01

    The jaws of herbivorous mammals are characterized by their large occlusal surface of the molar; high crown of the molar; long snout; etc. However, elephants, the biggest herbivorous mammal, have other characteristics. In the evolutionary trends of proboscidean skulls, concomitant with the increase in tusk size comes on the enlargement, antero-posterior shortening, dorso-ventral elongation of the cranium with increasing cheek teeth size. Naturally, the jaw follows the same evolutionary trends as the cranium.

  19. Edentulous site enhancement: a regenerative approach to the management of edentulous areas. Part 2: Peri-implant tissues.

    PubMed

    Calesini, Gaetano; Micarelli, Costanza; Coppè, Stefano; Scipioni, Agostino

    2009-02-01

    The appearance and long-term stability of peri-implant bone, mucosa, and gingiva determine the success of implant-supported prostheses from both the esthetic and functional standpoints. Any surgical or prosthetic technique that takes into consideration only some variables, or that only intervenes in a limited phase of treatment, is a potential source of a partially successful and/or unpredictable clinical outcome. This article describes the underlying principles and surgical-prosthetic procedures of a systematic regenerative approach, edentulous site enhancement (ESE). The goal of this approach is to improve the anatomy of edentulous sites. Applied to implant dentistry, this approach enables peri-implant tissue to be managed predictably, optimizing the functional and esthetic result of restorations with regard to treatment time, number of surgical stages, long-term prognosis, and incidence of complications. The principles underlying the ESE approach, which are independent of any specific implant system, are applicable in the majority of clinical situations, regardless of the esthetic requirements.

  20. Three-dimensional positional changes of teeth adjacent to posterior edentulous spaces in relation to age at time of tooth loss and elapsed time.

    PubMed

    Petridis, Haralampos P; Tsiggos, Nikolaos; Michail, Achilleas; Kafantaris, Sotirios N; Hatzikyriakos, Andreas; Kafantaris, Nikolaos M

    2010-06-01

    The purpose of this study was to study the stability of teeth adjacent to posterior edentulous spaces and correlate it with patient age and time lapse since tooth loss. Dental casts, panoramic radiographs, and questionnaires of patients treated in a University setting were employed. Teeth adjacent and opposing posterior edentulous spaces were examined for the following parameters: Supraeruption, rotation, space closure, and axial inclination. One hundred twenty three patients with 229 edentulous spaces were analyzed. Statistical analysis showed that the effects of "jaw", "gender", and "age group at the time of tooth loss" were not significant for any of the variables tested. The effect of time lapse since tooth loss was significant regarding the "amount of distal tooth inclination" (P<0.001), the "amount of distal tooth rotation" (P=0.004), and "space closure" (P=0.038). Post-hoc analysis of the "amount of distal tooth inclination" revealed a marked increase in inclination 5 years after tooth loss. Within the limitations of this study, it was concluded that in the group of patients studied, minor positional changes in teeth opposing or adjacent to posterior edentulous spaces had occurred. The greatest changes in position were recorded for mandibular teeth distal to edentulous spaces.

  1. An evidence-based protocol for immediate rehabilitation of the edentulous patient.

    PubMed

    Duello, George V

    2012-09-01

    A procedure using 4 dental fixtures with an immediate-loaded prosthesis for totally edentulous patients is the focus of an evidence-based analysis that uses modern methodologies to review an innovative clinical technique. The long-term outcomes for this surgical and prosthetic treatment for previously or newly edentulated patients by clinical teams worldwide, as well as the author's clinical personal data in a referral-based private practice, are reported in this investigation. An independent research dentist performed the literature review using terms that would identify articles commensurate with this article. The search years for keywords were limited to 2010 and 2011 because the purpose of the article was limited to current thinking and evidence on this specific technique. In this article, the author elected to restrict the literature search to journals that are commonly read and received in his clinical practice on a monthly basis. Because of the specific nature of this procedure, all historical references to the "all-on-4" procedure were also included in the database inquiries. The literature search revealed that the investigated technique has been reported worldwide by multiple authors using retrospective clinical analyses. In the maxillary jaw, the range of implants placed was 27 to 980 fixtures with 1 to 7 years of follow-up, demonstrating a cumulative implant success rate range of 92.5% to 100%. The mandibular arch demonstrated cumulative success rates of 93.8% to 100% with 1 to 10 years of follow-up with a range of 18 to 980 fixtures being placed. The investigator's own personal clinical statistics compared favorably with other clinical teams, with a total of 120 fixtures being placed in both jaws with 6 years of follow-up with a cumulative survival implant success rate of 100%. Continuous stability of the definitive final prosthesis was above 99% in the largest reported review and 100% for this author's private practice. Based on extensive reporting by

  2. Biochemical and mechanical characterization of Nereis worm jaws

    NASA Astrophysics Data System (ADS)

    Broomell, Christopher C.

    The ultimate goal of biomimetics is to elucidate the design principles governing performance in biological materials and apply them to engineering systems. Successful transfer of these principles will require a thorough understanding of the complex interplay between molecular composition, organization and mechanical properties of the material. This dissertation describes the mechanical and biochemical characterization of jaws from the marine polychaete Nereis virens. Nereid jaws possess remarkable mechanical properties considering their predominantly organic composition. Hardness and stiffness are comparable to human dentin. However, in stark contrast to dentin, in Nereis these properties are achieved without mineralization. The role of metal ions in jaw sclerotization is addressed. In the pristine state, Zn ions are concentrated at the tip and toothed-edge of the jaw and are critical for hardness and modulus; both properties are reduced by ˜70% following Zn removal by treatment with EDTA. Furthermore, metal content in the jaw can be manipulated by soaking Zn-depleted samples in metal solutions; the comparative effects of treatment with alternative transition metals under both dry and hydrated conditions are described. The molecular composition of the jaw is also addressed. Protein comprises ˜90% of the jaw mass; amino acid analysis indicates that histidine is increased in the hardened, Zn-rich tip. The major protein component in Nereid jaw extracts is purified and characterized by partial peptide mapping and isolation of a partial clone from a jaw pulp cDNA library. Nvjp-1 is a 38 kDa glycine- histidine-rich protein and is believed to be the principle structural protein in the hardened jaw tip. The effects of selected environmental factors on Nvjp-1 structure and assembly are described. Transition from low to high pH is accompanied by changes in secondary structure and a significant molecular elongation. Furthermore, exposure to transition metals, notably Zn and

  3. Morphology and evolution of the jaw suspension in lamniform sharks.

    PubMed

    Wilga, C D

    2005-07-01

    The morphology of the jaw suspension and jaw protrusion mechanism in lamniform sharks is described and mapped onto a cladogram to investigate how changes in jaw suspension and protrusion have evolved. This has revealed that several evolutionary modifications in the musculoskeletal apparatus of the jaws have taken place among lamniform sharks. Galeomorph sharks (Carcharhiniformes, Lamniformes, Orectolobiformes, and Heterodontiformes) have paired ethmopalatine ligaments connecting the ethmoid process of the upper jaw to the ethmoid region of the cranium. Basal lamniform sharks also acquired a novel single palatonasal ligament connecting the symphysis of the upper jaw to the cranium mid-ventral to the nasal capsule. Sharks in the family Lamnidae subsequently lost the original paired ethmopalatine ligament while retaining the novel palatonasal ligament. Thus, basal lamniform taxa (Mitsukurina owstoni, Carcharius taurus, Alopias vulpinnis) have increased ligamentous support of the lateral region of the upper jaw while derived species (Lamnidae) have lost this lateral support but gained anterior support. In previous studies the morphology of the jaw suspension has been shown to play a major role in the mechanism of upper jaw protrusion in elasmobranchs. The preorbitalis is the primary muscle effecting upper jaw protrusion in squalean (sister group to galeomorphs) and carcharhiniform (sister group to lamniforms) sharks. The preorbitalis originates from the quadratomandibularis muscle and inserts onto the nasal capsule in squalean and carcharhiniform sharks. Carcharhiniform sharks have evolved a subdivided preorbitalis muscle with the new division inserting near the ethmoid process of the palatoquadrate (upper jaw). Alopid sharks have also independently evolved a partially subdivided preorbitalis with the new division inserting at the base of the ethmoid process and surrounding connective tissue. Lamnid sharks have retained the two preorbitalis divisions but have modified

  4. Evaluation of Resting Tongue Position in Recently Extracted and Long Term Completely Edentulous Patients: A Prospective Interventional Study

    PubMed Central

    Kohli, Shivani; Mathew, Xavier K

    2017-01-01

    Introduction Presence of abnormal resting tongue position can lead to poor denture retention and stability. The prevalence of retracted tongue position has been found to be higher in partially edentulous subjects compared to dentate subjects and is greatest in completely edentulous individuals. Aim To evaluate resting tongue position in recently extracted and long term completely edentulous patients, and to evaluate the efficacy of achieving retracted tongue position by simple modification in complete denture along with certain tongue exercises. Materials and Methods A total of 62 study subjects were classified into two groups based on duration of edentulousness. Group A: Recently extracted completely edentulous subjects (<1 year), Group B: Long term completely edentulous subjects (>1-10 year). The patients with retracted tongue position were subjected to a simple modification in complete denture along with inclusion of certain tongue exercises. After eight months patients were recalled and evaluated. The data was analysed using SPSS statistical tests like mean, standard deviation, proportion, Chi square test and McNemar Test. Results Among the study subjects, 54.9% had retracted tongue position. Group B showed high proportion of retracted tongue position (68.8%) as compared to Group A. After the intervention, 42.8% study subjects gained normal resting tongue position. Conclusion Long term completely edentulous subjects presented retracted tongue position in higher percentage when compared to the recently extracted group. The interventional method employed for the subjects with retracted tongue position, played a significant role to assume normal resting tongue position and showed improvement in denture stability and retention. PMID:28571264

  5. Osteonecrosis of the jaw.

    PubMed

    Sambrook, Philip N; Ebeling, Peter

    2008-04-01

    Bisphosphonates are effective therapy for osteoporosis, Paget's disease, and metastatic bone disease. Generally, the side effects of bisphosphonates are minimal. Recently, an uncommon adverse reaction affecting the maxilla or mandible, called osteonecrosis of the jaw, has been reported, especially in those patients receiving high doses of bisphosphonates in the oncology setting. Regarding doses used to treat osteoporosis, clinicians must keep the very small potential absolute risk of jaw osteonecrosis in perspective and consider it in relation to the demonstrated benefit of bisphosphonates. Still, in a very small number of patients taking bisphosphonates, intractable, painful, nonhealing exposed bone may occur following dental extractions or denture irritation.

  6. [The biomechanical behaviour of the flexible acrylic partial prosthetics].

    PubMed

    Gheban, E; Forna, Norina Consuela

    2008-01-01

    The simulation methods constitute a modern method absolutely necessary at the forerunner stage of the practical unwinding of the research stages, outlining the precise directions for the practical application, the final results influencing the dental practice. Our study proposes itself to analyze through the method of the finite element the status of the tension and the deformations registered at the level of the partially extended indentured prosthetic field and at the level of the partially flexible acrylic prosthetics. The first step was constituted by the realization of CT followed by their scanning and the usage of the material constants. Following the tomographic computer exam at the patients submitted to the study, it was observed a resorption and an important atrophy at the level of the jaw indented crest, after a period of four months, with the flexible prosthetics type Valplast, this aspect having profound clinical and viability implications to the selected therapy solution. For the 3D reconstruction of the different types of partial extended indentation the Amira universal program was used for the 3D reconstructions for any type of Tomographic Computer. Following the 3D reconstructions of the information obtained on the tomographic computer on the images it can be observed an important resorption of the jaw bone in the area of the edentulous space with an acrylic flexible prosthetics. The intrusion of the silicon material Rubber type, as a viable solution for the reduction of the absorption rate and atrophy of the partially indented prosthetics field, has results proportional to the type of the force applied and the applying of this. The simulation of the real clinical situations following the contribution of the tomographic computer constitutes a highly important stage in the evaluation of the degree of resorption and atrophy at the level of the indented crests, process whose parameters are influenced by the factorial accumulation with a profound impact

  7. [Jaws of amphibians and reptiles].

    PubMed

    Tanimoto, Masahiro

    2005-04-01

    Big jaws of amphibians and reptiles are mainly treated in this article. In amphibians enlarged skulls are for the big jaw in contrast with human's skulls for the brain. For example, famous fossils of Homo diluvii testis are ones of salamanders in fact. In reptiles, mosasaur jaws and teeth and their ecology are introduced for instance.

  8. A population-based study of edentulism in the US: does depression and rural residency matter after controlling for potential confounders?

    PubMed Central

    2014-01-01

    Background Oral health is an integral component of general health and well-being. While edentulism has been examined in relation to socioeconomic status, rural residency, chronic disease and mental health, no study that we know of has examined edentulism and these factors together. The objective of this study was to determine whether depression and rural residency were significantly associated with partial and full edentulism in US adults after controlling for potential confounders. Methods 2006 Behavioral Risk Factor Surveillance Survey (BRFSS) data were analyzed to identify factors associated with increased odds of partial or full edentulism. This year of BRFSS data was chosen for analysis because in this year the standardized and validated Personal Health Questionnaire-8 (PHQ-8) was used to measure current depression. This measure was part of the optional questions BRFSS asks, and in 2006 33 states and/or territories included them in their annual surveillance data collection. Bivariate and logistic regression analyses were performed on weighted BRFSS data. Results Logistic regression analysis using either full or partial edentulism as the dependent variable yielded that rural residency or living in a rural locale, low and/or middle socioeconomic status (SES), depression as measured by the PHQ-8, and African American race/ethnicity were all independent risk factors when controlling for these and a number of additional covariates. Conclusions This study adds to the epidemiological literature by assessing partial and full edentulism in the US utilizing data from the CDC’s Behavioral Risk Factor Surveillance System (BRFSS). Examining data collected through a large national surveillance system such as BRFSS allows for an analysis that incorporates an array of covariates not available from clinically-based data alone. This study demonstrated that current depression and rural residency are important factors related to partial and full edentulism after controlling for

  9. Radiographic apparatus for photographing entire jaws

    SciTech Connect

    Nakano, K.

    1985-01-22

    This disclosure relates to a dental radiographic apparatus for photographing the entire jaw designed to control the rotation of a rotary arm such that the film surface of a film holder mounted at one end of the rotary arm may rotate and move substantially at equal speed substantially equidistantly along the dental arch and that the X-ray beams irradiated upon the film surface from an X-ray generator mounted at the other end of the arm may fall on the dental arch at any point thereof at right angles with the arch. The apparatus makes it possible to obtain a very clear tomographic picture of a curved plane of the entire jaws, the picture being free of a double image of the teeth, partial change in enlargement ratio of the image obtained, and partial difference in the shade of the image obtained.

  10. Relationships between facial morphology and activity of orofacial muscles in patients with a complete upper and a partial lower denture.

    PubMed

    Tallgren, A; Tryde, G

    1995-08-01

    In a sample of 30 partially edentulous subjects, provided with an immediate complete upper denture and a partial lower denture and followed for 2 years, a correlation analysis was performed between facial morphology, as measured by lateral head films, and EMG peak mean voltages of the anterior temporal and masseter muscles when clenched and during swallowing and chewing, and of the lip muscles during swallowing. At the pre-treatment stage, when the patients occluded on a residual anterior dentition, correlations between facial morphologic characteristics and peak mean voltages of the jaw closing muscles indicated stronger muscle activity in individuals with a square facial type. No significant associations were observed between muscle activity and the age of the subjects, which ranged from 36 to 71 years. After placement and use of the dentures a significant forward-upward rotation of the mandible with a decrease in overbite occurred, as a result of resorption of the edentulous maxillary ridge. At the 1 year stage of denture use, the elevator activity showed no significant correlations with facial morphology. On the other hand, negative correlations were observed especially between the anterior temporal activity and anterior overbite. Similar negative correlations were observed for the lip activity during swallowing, especially of the upper lip. These findings suggest occlusal contact between the incisors during the various functions in subjects with a small overbite. The findings further suggest that the anterior temporal and the upper lip muscles are sensitive to changes in anterior occlusal relations of the dentures.

  11. Modern application of the Skinner vertical movement stress director for distal extension partial removable dental prostheses: A clinical report.

    PubMed

    Schulz, Kyle S; Downs, Donald; Cagna, David R

    2013-07-01

    This article describes the prosthetic rehabilitation of a partially edentulous patient with a partial removable dental prosthesis (PRDP) designed to dissipate stress transmission to the denture foundation and abutment teeth. The Skinner stress director is considered an alternative design for managing partially edentulous patients.

  12. Additively manufactured sub-periosteal jaw implants.

    PubMed

    Mommaerts, M Y

    2017-02-28

    Severe bone atrophy jeopardizes the success of endosseous implants. This technical note aims to present the innovative concept of additively manufactured sub-periosteal jaw implants (AMSJIs). Digital datasets of the patient's jaws and wax trial in occlusion are used to segment the bone and dental arches, for the design of a sub-periosteal frame and abutments in the optimal location related to the dental arch and for the design of the suprastructure. The implants and suprastructure are three-dimensionally (3D) printed in titanium alloy. The provisional denture is 3D-printed in polymer. AMSJIs offer an alternative approach for patients with extreme jaw bone atrophy. This report refers to the use of this technique for full maxillary rehabilitation, but partial defects in either jaw and extended post-resection defects may also be approached using the same technique. This customized, prosthesis-driven reverse-engineering approach avoids bone grafting and provides immediate functional restoration with one surgical session.

  13. Implant Supported Mandibular Overdenture: A Viable Treatment Option for Edentulous Mandible

    PubMed Central

    Lambade, Pravin; Gundawar, Sham

    2014-01-01

    The prosthetic management of the edentulous patient has long been a major challenge. Complete maxillary and mandibular dentures have been the traditional standard of care. However, most of the patients report problems adapting to their mandibular denture due to a lack of comfort, retention, stability and inability to masticate. Implant-supported overdentures have been a common treatment for edentulous patients for the past 20 years and predictably achieve good clinical results. Implant supported overdentures offer many practical advantages over conventional complete dentures and removable partial dentures. These include decreased bone resorption, reduced prosthesis movement, better esthetics, improved tooth position, better occlusion, increased occlusal function and maintenance of the occlusal vertical dimension. This article presents a design and fabrication technique of the implant-retained overdenture that uses four freestanding mandibular implants. PMID:24995252

  14. Ewing's tumor of the jaw.

    PubMed

    Wood, R E; Nortje, C J; Hesseling, P; Grotepass, F

    1990-01-01

    Previous reports have focused on the fact that laminar periosteal new bone is a common radiologic sign of Ewing's sarcoma of the jaws. Critical analysis of the literature does not lead to this conclusion. A case is reported and radiologic appearances described. A review of the literature shows striking clinical and radiologic similarities to osteogenic sarcoma of the jaws. A differential radiologic interpretation of Ewing's sarcoma of the jaws is offered.

  15. Impact of fixed implant supported prostheses in edentulous patients: protocol for a systematic review

    PubMed Central

    López, Carolina S; Saka, Constanza H; Rada, Gabriel; Valenzuela, Daniela D

    2016-01-01

    Introduction Edentulism is a debilitating and irreversible condition described as the ‘final marker of disease burden for oral health’. Therapy with dental implants is being used on a large scale to replace missing teeth and to rehabilitate edentulous patients with overdentures and implant supported fixed dentures as a method of solving the problem of instability and lack of retention associated with conventional removable prostheses. Fixed implant supported prostheses are an alternative for implant rehabilitation treatment that allow patients to have new fixed teeth. They can be indicated in partial or total edentulous patients, and they can replace single teeth, or teeth and supporting tissues (hybrid prosthesis). They overcome the limitations of conventional dentures, increasing stability and retention, providing functional and psychological advantages for the patients. Methods and analysis We will electronically search for randomised controlled trials evaluating the effects of fixed implant supported prostheses in edentulous patients in the following databases: Pubmed/MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. We will also try to obtain literature screening references of included studies, searching for trial protocols in the WHO International Clinical Trials Registry Platform, reviewing International Team for Implantology conference proceedings and searching for non-published studies through Open Gray. Two researchers will independently undertake selection of studies, data extraction and assessment of the quality of the included studies. Data synthesis and subgroup analyses will be performed using special Review Manager software. Data will be combined in a meta-analysis using a random effects model. Results The results will be presented as risk ratios for dichotomous data, and as mean difference or standardised mean difference for continuous data. Ethics and dissemination No ethics approval is considered necessary. The results

  16. Impact of fixed implant supported prostheses in edentulous patients: protocol for a systematic review.

    PubMed

    López, Carolina S; Saka, Constanza H; Rada, Gabriel; Valenzuela, Daniela D

    2016-02-23

    Edentulism is a debilitating and irreversible condition described as the 'final marker of disease burden for oral health'. Therapy with dental implants is being used on a large scale to replace missing teeth and to rehabilitate edentulous patients with overdentures and implant supported fixed dentures as a method of solving the problem of instability and lack of retention associated with conventional removable prostheses. Fixed implant supported prostheses are an alternative for implant rehabilitation treatment that allow patients to have new fixed teeth. They can be indicated in partial or total edentulous patients, and they can replace single teeth, or teeth and supporting tissues (hybrid prosthesis). They overcome the limitations of conventional dentures, increasing stability and retention, providing functional and psychological advantages for the patients. We will electronically search for randomised controlled trials evaluating the effects of fixed implant supported prostheses in edentulous patients in the following databases: Pubmed/MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. We will also try to obtain literature screening references of included studies, searching for trial protocols in the WHO International Clinical Trials Registry Platform, reviewing International Team for Implantology conference proceedings and searching for non-published studies through Open Gray. Two researchers will independently undertake selection of studies, data extraction and assessment of the quality of the included studies. Data synthesis and subgroup analyses will be performed using special Review Manager software. Data will be combined in a meta-analysis using a random effects model. The results will be presented as risk ratios for dichotomous data, and as mean difference or standardised mean difference for continuous data. No ethics approval is considered necessary. The results of this study will be disseminated via peer reviewed publications and

  17. Edentulous site enhancement: a regenerative approach for the management of edentulous areas. Part 1. Pontic areas.

    PubMed

    Calesini, Gaetano; Micarelli, Costanza; Coppè, Stefano; Scipioni, Agostino

    2008-10-01

    The successful esthetic integration of a prosthesis is dependent on the anatomic site in which the restoration is inserted. Edentulous site enhancement is a regenerative approach based on the following: (1) anatomic evidence that the morphology of soft tissues is dependent on the underlying support (bone, roots, implants) but also significantly influenced by overlying structures (fixed or removable prostheses); (2) histologic evidence of the remarkable regenerative capacity of the newly formed tissue that develops during healing by secondary intention; (3) clinical evidence that it is possible to guide the formation of this new regenerative tissue by creating a support with proper morphology and a highly polished surface; (4) observations that positive pressure exerted by alimentary bolus and negative pressure produced by deglutition affect the growth of this tissue healing by second intention; and (5) the application of appropriate oral hygiene techniques to guide tissue healing and maintain its integrity. The edentulous site enhancement approach is simple, practical, and predictable and offers minimal postoperative complications. This paper describes the edentulous site enhancement approach as applied in the pontic areas.

  18. Solitary plasmacytoma of the jaw

    PubMed Central

    Marotta, Serena; Di Micco, Pierpaolo

    2010-01-01

    Solitary plasmacytoma may be considered as a rare neoplasm of head and neck and is a different disease compared to multiple myeloma. The main difference is related to the better clinical prognosis of solitary plasmacytoma, which may be clinically silent for several years but several local recurrences may be possible once diagnosed and treated. Clinical signs and symptoms of solitary plasmacytoma are related to bone pain and possible bone fractures. Partial local impairment of local bone function may be present. Bone swelling and local involvement of mucosa and local soft tissue may be revealed. Systemic findings related to the production of monoclonal protein are usually not present and a monoclonal spike in serum electrophoresis may be absent as the monoclonal Bence–Jones protein in the urine. Other systemic dysfunctions as systemic bone marrow involvement with related anemia and absent thrombocytopenia. However, although very rare, solitary plasmacytoma of the jaw may have several clinical presentations and here we review clinical differences reported in the literature. PMID:22282681

  19. Development of teeth and jaws in the earliest jawed vertebrates.

    PubMed

    Rücklin, Martin; Donoghue, Philip C J; Johanson, Zerina; Trinajstic, Kate; Marone, Federica; Stampanoni, Marco

    2012-11-29

    Teeth and jaws constitute a model of the evolutionary developmental biology concept of modularity and they have been considered the key innovations underpinning a classic example of adaptive radiation. However, their evolutionary origins are much debated. Placoderms comprise an extinct sister clade or grade to the clade containing chondrichthyans and osteichthyans, and although they clearly possess jaws, previous studies have suggested that they lack teeth, that they possess convergently evolved tooth-like structures or that they possess true teeth. Here we use synchrotron radiation X-ray tomographic microscopy (SRXTM) of a developmental series of Compagopiscis croucheri (Arthrodira) to show that placoderm jaws are composed of distinct cartilages and gnathal ossifications in both jaws, and a dermal element in the lower jaw. The gnathal ossification is a composite of distinct teeth that developed in succession, polarized along three distinct vectors, comparable to tooth families. The teeth are composed of dentine and bone, and show a distinct pulp cavity that is infilled centripetally as development proceeds. This pattern is repeated in other placoderms, but differs from the structure and development of tooth-like structures in the postbranchial lamina and dermal skeleton of Compagopiscis and other placoderms. We interpret this evidence to indicate that Compagopiscis and other arthrodires possessed teeth, but that tooth and jaw development was not developmentally or structurally integrated in placoderms. Teeth did not evolve convergently among the extant and extinct classes of early jawed vertebrates but, rather, successional teeth evolved within the gnathostome stem-lineage soon after the origin of jaws. The chimaeric developmental origin of this model of modularity reflects the distinct evolutionary origins of teeth and of component elements of the jaws.

  20. Augmentation of an anterior edentulous ridge for fixed prosthodontics with combined use of orthodontics and surgery: a clinical report.

    PubMed

    Capri, Diego; Albehbehani, Yousif; Smukler, Hyman

    2003-08-01

    Untreated periodontitis may lead to tooth and tissue loss that can result in diminished masticatory function and esthetic deformities. Combined periodontal/prosthodontic treatment for patients with advanced periodontal disease has been well documented, and treatment results can often be improved with the use of adjunctive orthodontic treatment such as forced eruption. This clinical report describes a method of preprosthetic preparation of an edentulous ridge for a fixed partial denture that incorporates the combined use of orthodontics and surgical ridge augmentation.

  1. Predictors and correlates of edentulism in healthy older people.

    PubMed

    Starr, John M; Hall, Roanna

    2010-01-01

    To review peer-reviewed, original research studies published in 2008-2009 that present data relating to the predictors and correlates of edentulism and tooth loss in older adults. Edentulism rates vary markedly between countries and between urban and rural settings within countries. Rates are generally falling over time, but this reduction largely reflects a cohort effect on tooth loss in childhood and young adulthood. Socioeconomic factors, along with accompanying lifestyles and health behaviours remain strong predictors of edentulism, many of these factors relate to peak prior intelligence. Immunological mechanisms of tooth loss are becoming elucidated. Edentulism, itself, predicts mortality and correlates with a wide range of health outcomes, but these, in turn, also correlate with predictors of tooth loss such as peak prior intelligence. Edentulism correlates separately from these lifelong traits with measures of self-esteem and quality of life. Edentulism is important as a correlate of self-esteem and quality of life in older adults. It is also a useful marker of socioeconomic status earlier in life.

  2. Implications of edentulism on quality of life among elderly.

    PubMed

    Rodrigues, Suely Maria; Oliveira, Ana Cristina; Vargas, Andréa Maria Duarte; Moreira, Allyson Nogueira; E Ferreira, Efigênia Ferreira

    2012-01-01

    This study aimed was to test the association between quality of life and edentulism among elderly individuals in a city in southeastern Brazil. This cross-sectional study was carried out with 163 individuals aged 60 years or older, functionally independent and non-institutionalized. Data were collected with a questionnaire and oral examination. The edentulism was the dependent variable. The independent variables were sex, age, household income and quality of life (WHOQOL-Old) and their scores. To assess the association between the dependent variable and independent variables was used bivariate analysis (p < 0.10). Poisson regression model was performed, adjusting for age and sex. The average age of participants was 69 years (± 6.1), 68.7% were female and 52.8% were diagnosed as completely edentulous (90% CI: 0.33-1.24). When the independent variables were associated to the prevalence of edentulism, statistically significant associations were found for age (p = 0.03) and social participation dimension of the WHOQOL-Old (p = 0.08). In the Poisson regression, social participation remained statistically associated to edentulism {RP = 2.12 [90% CI (1.10-4.00)]}. The social participation proved to have a significant association to edentulism, thereby attesting to the negative effect of this condition on social aspects.

  3. Implications of Edentulism on Quality of Life among Elderly

    PubMed Central

    Rodrigues, Suely Maria; Oliveira, Ana Cristina; Vargas, Andréa Maria Duarte; Moreira, Allyson Nogueira; e Ferreira, Efigênia Ferreira

    2012-01-01

    This study aimed was to test the association between quality of life and edentulism among elderly individuals in a city in southeastern Brazil. This cross-sectional study was carried out with 163 individuals aged 60 years or older, functionally independent and non-institutionalized. Data were collected with a questionnaire and oral examination. The edentulism was the dependent variable. The independent variables were sex, age, household income and quality of life (WHOQOL-Old) and their scores. To assess the association between the dependent variable and independent variables was used bivariate analysis (p < 0.10). Poisson regression model was performed, adjusting for age and sex. The average age of participants was 69 years (± 6.1), 68.7% were female and 52.8% were diagnosed as completely edentulous (90% CI: 0.33–1.24). When the independent variables were associated to the prevalence of edentulism, statistically significant associations were found for age (p = 0.03) and social participation dimension of the WHOQOL-Old (p = 0.08). In the Poisson regression, social participation remained statistically associated to edentulism {RP = 2.12 [90% CI (1.10–4.00)]}. The social participation proved to have a significant association to edentulism, thereby attesting to the negative effect of this condition on social aspects. PMID:22470281

  4. Human jaw and muscle modelling.

    PubMed

    Peck, Christopher C; Hannam, Alan G

    2007-04-01

    Dynamic mathematical modelling is an invaluable method to help understand the biomechanics of the anatomically and functionally complex masticatory system. It provides insight into variables which are impossible to measure directly such as joint loads and individual muscle tensions, and into physical relationships between jaw structure and function. Individual parameters can be modified easily to understand their influence on function. Our models are constructed with best available structural and functional data, and evaluated against human jaw behaviour. Image data provide hard and soft tissue morphology and the jaw's inertial properties. The drive to the system is provided by actuators which simulate active and passive jaw muscle properties. In whole-jaw modelling, muscle models which behave plausibly rather than mimic the ultra-structural cross-bridge interactions are common since they are computationally feasible. Whole-jaw models have recently incorporated flexible finite-elements to explore tissue distortion in the temporomandibular joint and tongue movements. Furthermore, the jaw has been integrated with laryngeal models to explore complex tasks such as swallowing. These dynamic models have helped better understand joint loading, movement constraints and muscle activation strategies. Future directions will include further incorporation of rigid and flexible model dynamics and the creation of subject-specific models to better understand the functional implications of pathology.

  5. Removable partial overdentures for the irradiated patient

    SciTech Connect

    Rosenberg, S.W. )

    1990-10-01

    Patients who have received radiotherapy to the head and neck area must avoid dental extractions and seek simplicity in treatment and home care follow-up. For partially edentulous patients, removable partial overdenture therapy can fulfill these goals while maintaining the high level of function and aesthetics desired by patients.11 references.

  6. Six-implant-supported immediate fixed rehabilitation of atrophic edentulous maxillae with tilted distal implants.

    PubMed

    Wentaschek, S; Hartmann, S; Walter, C; Wagner, W

    2017-12-01

    The aim of this retrospective study was to evaluate the treatment outcome of six Bredent blueSky™ implants (Bredent GmbH, Senden, Germany) immediately loaded with a fixed full-arch prosthesis (two tilted posterior and four axial frontal and premolar implants). All 10 patients with atrophic edentulous maxillae being treated with a standardized procedure from 09/2009 to 01/2013, who had a follow-up of at least 3 years, were included. Sixty implants were placed to support 10 screwed prostheses. Twenty-one of them were inserted in fresh extraction sockets. Lab-side-prepared provisional fixed prostheses were placed at the day of implantation. Periotest (PT) values and implant stability quotient (ISQ) were measured after implant surgery and after 3 months of healing in all patients. The analyzed implants were in function in mean 64 ± 13 months (range 42 to 84 months). One axial and two tilted implants failed in three patients. The mean PT values decreased, and ISQ increased significantly after the first 3 months at the osseointegrated tilted and axial implants. With an area under the curve of 0.503 and 0.506 in the receiver operating characteristic, the PT values and the ISQ were unspecific parameters and unsuitable as a predictor for the risk of non-osseointegration. Within the limits of this small group (n = 10 patients/60 implants), the failure rate of the analyzed implant system (n = 3 respective 5% implant loss) seems to be comparable with other immediate-loading protocols. The failure rate of tilted implants in the atrophic upper jaw was quite high, but the aimed treatment concept could be achieved in every patient. The rehabilitation of the posterior region in edentulous maxilla remains a challenge.

  7. Posterior jaws rehabilitated with partial prostheses supported by 4.0 x 4.0 mm or by longer implants: One-year post-loading results from a multicenter randomised controlled trial.

    PubMed

    Felice, Pietro; Checchi, Luigi; Barausse, Carlo; Pistilli, Roberto; Sammartino, Gilberto; Masi, Irene; Ippolito, Daniela Rita; Esposito, Marco

    2016-01-01

    To evaluate whether 4.0 x 4.0 mm dental implants could be an alternative to implants at least 8.5 mm long, which were placed in posterior jaws, in the presence of adequate bone volumes. One hundred and fifty patients with posterior (premolar and molar areas) jaws having at least 12.5 mm bone height above the mandibular canal or 11.5 mm below the maxillary sinus, were randomised according to a parallel group design, in order to receive one to three 4.0 mm-long implants or one to three implants which were at least 8.5 mm-long, at three centres. All implants had a diameter of 4.0 mm. Implants were loaded after 4 months with definitive screw-retained prostheses. Patients were followed up to 1-year post-loading and outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes. Seventy-five patients were randomly allocated to each group. One patient dropped out after the 4-month post-loading evaluation from the long implant group. Up to 1-year post-loading, 3 patients lost one 4.0 mm-long implant each in comparison to 2 patients who lost one long implant each (difference in proportion = 0.013; 95% CI: -0.058 to 0.087; P = 0.506). All failures occurred before loading, the failed implants were replaced and the delivery of two prostheses in each group was delayed for several months (difference in proportion = 0.0004; 95% CI: -0.068 to 0.069; P = 0.685). Three short implant patients experienced three complications versus 2 long implant patients (difference in proportion = 0.013; 95% CI: -0.058 to 0.087; P = 0.506). There were no statistically significant differences in prosthesis failures, implant failures and complications. Patients with short implants lost on average 0.53 mm of peri-implant bone and patients with longer implants lost 0.57 mm. There were no statistically significant differences in bone level changes up to 1 year between short and long implants (mean difference = 0.038 mm; 95% CI: -0.068 to 0.138; P = 0

  8. A method for studying jaw muscle activity during standardized jaw movements under experimental jaw muscle pain.

    PubMed

    Sae-Lee, Daraporn; Wanigaratne, Kamal; Whittle, Terry; Peck, Christopher C; Murray, Greg M

    2006-10-30

    This paper describes a method for studying superficial and deep jaw muscle activity during standardized jaw movements under experimental jaw muscle pain. In 22 healthy adults, pain was elicited in the right masseter muscle via tonic infusion of 4.5% hypertonic saline and which resulted in scores of 30-60 mm on a 100-mm visual analogue scale. Subjects performed tasks in five sessions in a repeated measures design, i.e., control 1, test 1 (during hypertonic or isotonic saline infusion), control 2 (without infusion), test 2 (during isotonic or hypertonic saline infusion), control 3 (without infusion). During each session, subjects performed maximal clenching and standardized jaw tasks, i.e., protrusion, lateral excursion, open/close, chewing. Mandibular movement was recorded with a 6-degree-of-freedom tracking system simultaneously with electromyographic (EMG) activity from the inferior head of the lateral pterygoid muscle with fine-wire electrodes (verified by computer tomography), and from posterior temporalis, the submandibular muscle group and bilateral masseter muscles with surface electrodes. EMG root mean square values were calculated at each 0.5 mm increment of mandibular incisor movement for all tasks under each experimental session. This establishes an experimental model for testing the effects of pain on jaw muscle activity where the jaw motor system is required to perform goal-directed tasks, and therefore should extend our understanding of the effects of pain on the jaw motor system.

  9. Diagnosis and treatment of dynamic closed-mouth jaw locking in a dog.

    PubMed

    Frazho, Jean K; Tano, Cheryl A; Ferrell, Eric A

    2008-09-01

    A 5-year-old neutered male English Bulldog was evaluated for intermittent closed-mouth jaw locking of approximately 1 week's duration. Initial physical examination revealed a nonpainful inability to open the jaw with and without manual assistance; however, manipulation of the jaw after the dog was sedated for diagnostic imaging restored jaw function. Anesthesia was subsequently induced, and computed tomography was performed with the jaw open and closed; contrast agent-enhanced images of the closed jaw were also obtained. No abnormalities of the temporomandibular joints or retrobulbar space were detected. Fluoroscopic examination of movement of the temporomandibular joints revealed a dynamic interference of the rostrodorsal aspect of the coronoid process of the left mandibular ramus with the medial surface of the frontal process of the left zygomatic bone or the left orbital ligament. Partial excision of the coronoid process of the left mandibular ramus was performed. The dog recovered without complication and was able to open and close its jaw and eat within 6 hours after surgery. No additional episodes of jaw locking were detected during the 6 months after surgery. To the authors' knowledge, closed-mouth jaw locking in animals attributable to dynamic interference of the rostrodorsal aspect of the coronoid process of a mandibular ramus with the medial surface of the frontal process of a zygomatic bone or an orbital ligament has not been described. Surgical excision of the coronoid process of the mandibular ramus appeared to provide a successful outcome in the dog of this report.

  10. Osteonecrosis of the jaws in periodontal patients with a history of bisphosphonates treatment.

    PubMed

    Ficarra, G; Beninati, F; Rubino, I; Vannucchi, A; Longo, G; Tonelli, P; Pini Prato, G

    2005-11-01

    Osteonecrosis of the jaws is being increasingly reported in patients with bone metastasis from a variety of solid tumours and disseminated multiple myeloma receiving intra-venous bisphosphonates. The signs and symptoms that may occur before the appearance of clinical evident osteonecrosis include changes in the health of periodontal tissues, non-healing mucosal ulcers, loose teeth and unexplained soft-tissue infection. A series of nine periodontally involving patients showing osteonecrosis of the jaws that appeared following the intra-venous use of bisphosphonates is reported. Nine consecutive patients with osteonecrosis of the jaws were prospectically studied. Patients' past medical histories and the drugs that they had received for their malignant disease were systematically documented. Clinical, histopathological and radiographic features and proposal for treatment modalities of osteonecrosis are also reported. Of the nine patients (six women and three men) observed, all had osteonecrosis in the mandible; two had maxillary involvement as well. All nine patients had a history of extraction of periodontally hopeless teeth preceding the onset of osteonecrosis. In two patients, the lesions also appeared in edentulous areas spontaneously. All the patients had received intra-venous bisphosphonates as treatment for their disseminated haematological neoplasms or metastatic bone disease. The duration of bisphosphonate therapy at presentation ranged from 10 to 70 months (median: 33 months). Jaw osteonecrosis appears to be associated with the intra-venous use of bisphosphonates. Dental professionals should be aware of this potentially serious complication in periodontal patients receiving long-term treatment with bisphosphonates. Copyright (c) Blackwell Munksgaard, 2005.

  11. Impaired polymorphonuclear neutrophils in the oral cavity of edentulous individuals.

    PubMed

    Rijkschroeff, Patrick; Loos, Bruno G; Nicu, Elena A

    2017-10-01

    Oral health is characterized by functional oral polymorphonuclear neutrophils (oPMNs). Edentulism might be associated with a loss of oPMNs because these cells enter the oral cavity primarily through the gingival crevices. The main aim of this study was to investigate the numbers of oPMNs in rinse samples obtained from edentulous (n = 21) and dentate (n = 20) subjects. A second study aim was to investigate possible differences between oPMNs and peripheral blood polymorphonuclear neutrophils (cPMNs). Apoptosis/necrosis and cell-activation markers (CD11b, CD63 and CD66b) were analyzed using flow cytometry. Reactive oxygen species (ROS) production was determined either without stimulation (constitutive) or in response to 10 μM phorbol myristate acetate or Fusobacterium nucleatum. The edentulous subjects presented with lower oPMN counts and higher percentages of apoptotic/necrotic oPMNs compared with dentate subjects. Furthermore, oPMNs from edentulous donors expressed low levels of all three activation markers and low constitutive ROS. In contrast, oPMNs from dentate subjects expressed high levels of all three activation markers and a higher level of constitutive ROS than cPMNs. When challenged, oPMNs from edentulous subjects showed no upregulation in ROS production, whereas oPMNs from dentate subjects retained their ability to respond to stimulation. The functional characteristics of cPMNs were comparable between edentulous and dentate subjects. This study demonstrates that despite having functional cPMNs, edentulous subjects have low oPMN numbers that are functionally impaired. © 2017 The Authors. Eur J Oral Sci published by John Wiley & Sons Ltd.

  12. Pediatric jaw tumors: Our experience.

    PubMed

    Saxena, Susmita; Kumar, Sanjeev; Pundir, Siddharth

    2012-01-01

    Reports of series of central jaw tumours in children are rare hence predicting their biological behaviour as well as treatment, prognosis have not been documented from this part of the world. To study retrospectively, the paediatric central jaw tumours, reported to our institute with relation to site of occurrence, presentation and biological behaviour. All consecutive patients (<18 years), between 2004-2010, histologically diagnosed as having an intraosseous tumour or tumour-like lesions formed the study population. Patients fulfilling the inclusion criteria were only considered for further study. The entire study material was analyzed and grouped into various categories for logical conclusions. The data accumulated were grouped, entered and analyzed. Sixty-one cases fulfilled the criteria. Gender distribution was equal, with mandible predominance (2.2:1) and a predominance of non-odontogenic lesions (2:1). There were 4 malignant and 57 benign conditions. Anterior jaw lesions were 23 while 38 were present in the posterior region of jaws (1:1:6). The pattern of central jaw tumours presentation in children from this part of India has been documented. In this study, paediatric jaw tumours are less common compared to those in adults with non-odontogenic tumours being common. The finding of the present study indicates that an impacted tooth, beyond the eruption time deserves more attention for the reason of associated pathologies in children.

  13. Posterior jaws rehabilitated with partial prostheses supported by 4.0 x 4.0 mm or by longer implants: Four-month post-loading data from a randomised controlled trial.

    PubMed

    Esposito, Marco; Barausse, Carlo; Pistilli, Roberto; Checchi, Vittorio; Diazzi, Michele; Gatto, Maria Rosaria; Felice, Pietro

    2015-01-01

    To evaluate whether 4.0 x 4.0 mm dental implants could be an alternative to implants at least 8.5 mm long, which were placed in posterior jaws in the presence of adequate bone volumes. One hundred and fifty patients with posterior (premolar and molar areas) mandibles having at least 12.5 mm bone height above the mandibular canal or 11.5 mm bone height below the maxillary sinus, were randomised according to a parallel group design, in order to receive one to three 4.0 mm-long implants or one to three implants which were at least 8.5 mm long, at three centres. All implants had a diameter of 4.0 mm. Implants were loaded after 4 months with definitive screw-retained prostheses. Patients were followed up to 4-month post-loading and outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes. No patients dropped-out before the 4-month evaluation. Three patients experienced the early failures of one 4.0 mm-long implant each, in comparison to two patients who lost one long implant each (difference in proportion = 0.01; 95% CI -0.06 to 0.09; P = 0.50). Consequently, two prostheses in each group could not be delivered as planned (difference in proportion = 0; 95% CI -0.07 to 0.07; P = 0.69), and one patient from each group is still waiting to have their prostheses delivered. Three short implant patients experienced three complications versus two long implant patients (difference in proportion = 0.01; 95% CI -0.06 to 0.09; P = 0.50). There were no statistically significant differences in prosthesis failures, implant failures and complications. Patients with short implants lost on average 0.38 mm of peri-implant bone at 4 months and patients with long mandibular implants lost 0.42 mm. There were no statistically significant differences in bone level changes up to 4 months between short and long implants (mean difference = 0.04 mm; 95% CI: -0.041 to 0.117; P = 0.274). Four months after loading, 4.0 x 4.0 mm implants

  14. [Indications for removable partial dentures].

    PubMed

    van Waas, M A J

    2009-11-01

    Since there are many ways of preserving a natural dentition, if necessary with support of solitary crowns and fixed partial dentures, sometimes on dental implants, removable partial dentures are nowadays primarily indicated in patients with complaints about missing teeth in the aesthetic zone, which cannot be solved in another way. In addition to this, a removable partial denture is indicated in patients with extremely reduced dentitions or large or multiple edentulous areas, in patients with severe periodontitis or excessive loss of alveolar bone, in patients who are physically or emotionally vulnerable, as an interim solution on the way to edentulousness, as a temporary solution waiting for more extensive treatment and for patients who cannot afford an alternative.

  15. The alveolar process of the edentulous maxilla in periodontitis and non-periodontitis subjects.

    PubMed

    Lindhe, Jan; Cecchinato, Denis; Bressan, Eriberto A; Toia, Marco; Araújo, Mauricio G; Liljenberg, Birgitta

    2012-01-01

    Early implant failures may document that the bone tissue or the wound-healing process following installation surgery was compromised. Subjects who have lost teeth for periodontal reasons exhibit more earlier implant failures than subjects who had experienced tooth loss for other reasons. To describe the tissue of the fully healed extraction sites in subjects who had lost teeth as a result of periodontitis or for other reasons. Thirty-six otherwise healthy, partially dentate subjects with fully healed edentulous portions in the posterior maxilla were included. Nineteen of these subjects had lost teeth because of advanced periodontitis (group P) and 17 for other reasons (group NP). Using a trephine drill, a 4-6 mm long hard tissue specimen was harvested. The biopsies were decalcified, embedded in paraffin, sectioned, stained and examined. The edentulous posterior maxilla was comprised of 47.1 ± 11% lamellar bone, 8.1 ± 7.1% woven bone, 4.3 ± 3.1% osteoid and 16.5 ± 10.4% bone marrow. There were no significant differences in the tissue composition of post-extraction sites of (i) P and NP subjects and (ii) premolar and molar sites. More than 50% of the edentulous maxilla was comprised of mineralized bone (lamellar and woven bone). The bone trabeculae frequently appeared to have a random orientation. The direction of the trabeculae rather than the lack of mineralized bone tissue may explain the clinical impression that the bone in the posterior maxilla provides limited resistance to mechanical instrumentation. © 2011 John Wiley & Sons A/S.

  16. Silent period-dentate, edentulous, and patients with craniomandibular dysfunction.

    PubMed

    Goiato, Marcelo Coelho; Haddad, Marcela Filiè; dos Santos, Daniela Micheline; Garcia, Alício Rosalino; Zuim, Paulo Renato Junqueira; Zavanelli, Adriana Cristina

    2010-09-01

    The record of electrical activity of elevator muscles in mandible is important for the evaluation of muscular potency and diagnosis of neuromuscular pathologies, which allows prevention and treatment. The aim of this study was to define silent periods (SPs) and the importance in dentistry and compare the SPs in masticatory muscles of dentate and edentulous patients wearing prosthesis considering the presence or absence of craniomandibular dysfunction (CMD). Literature review in PubMed database. Silent periods are isolated pulses of transcranial magnetic stimulation in the primary motor cortex during voluntary muscular activity that generates an interruption of muscular activity for hundredths of milliseconds. The SP duration depends on the patient (dentate or edentulous), type of stimulus, and presence of CMD. The SP is higher in complete edentulous patients and in individuals with occlusal disharmonies than in dentate patients without CMDs. The treatment of CMDs through occlusal therapy decreases SP duration.

  17. Lack of dental insurance is correlated with edentulism.

    PubMed

    Simon, Lisa; Nalliah, Romesh P; Seymour, Brittany

    2015-01-01

    The correlation between insurance status and edentulism has not previously been reported in a population with known access to a dentist, and little is known about patient demographics in corporate dental settings. This study investigated patient demographics of a former dental franchise in Chicopee, Massachusetts, and examined a correlation between dental insurance and edentulism in this group. The correlation of edentulism with age, gender, and dental risk factors (diabetes, temporomandibular disorder, trouble with previous dental work, or oral sores and ulcers) was also examined. This was a retrospective case study. Age, gender, and presence of dental risk factors were recorded from the patient medical history intake form. Dentate status was recorded from patient odontograms. Dental insurance status was obtained from billing records. Data was aggregated and deidentified. Descriptive and bivariate statistics and logistic regression models were used to identify associations (p-value ≤ 0.05 significance). Of 1,123 records meeting inclusion criteria, 52.54 percent of patients had dental insurance, 26.27 percent had at least one dental risk factor, and 18.17 percent were edentulous. Age and insurance status were significantly correlated with edentulism. Correcting for age, individuals without insurance were 1.56 times as likely to be edentulous. This case study provides insight into patient demographics that might seek care in a corporate setting and suggests that access to a dentist alone may not be adequate in preserving the adult dentition; dental insurance may also be important to health. As the corporate dental practice model continues to grow, these topics deserve further study.

  18. Jaw stretch reflexes in children.

    PubMed

    Finan, Donald S; Smith, Anne

    2005-07-01

    The substantial morphological transformations that occur during human development present the nervous system with a considerable challenge in terms of motor control. Variability of skilled motor performance is a hallmark of a developing system. In adults, the jaw stretch reflex contributes to the functional stability of the jaw. We have investigated the response properties of the jaw stretch reflex in two groups of young children and a group of young adults. Response latencies increased with development, and all age groups produced stimulus-magnitude-dependent increases in reflex gain and resulting biting force. Reflex gain was largest for the older children (9-10 years), yet net increases in resulting biting force were comparable across age groups. These data and earlier experiments suggest that oral sensorimotor pathways mature throughout childhood in concert with the continued acquisition of complex motor skills.

  19. Introduction to the JAWS Program

    NASA Technical Reports Server (NTRS)

    Mccarthy, John

    1987-01-01

    The JAWS Project is the Joint Airport Weather Studies project conceived in 1980 jointly between the National Center for Atmospheric Research and the Univ. of Chicago. The objectives of the program are threefold: (1) Basic scientific characterization of the microbursts and the statistics of microbursts occurrence; (2) Detection and warning, using the Low Level Wind Shear Alert System (LLWSAS) operation and performance; and (3) Doppler radar and airborne systems. These goals and the operation of the JAWS system in general are discussed in detail.

  20. Edentulism, beaks, and biomechanical innovations in the evolution of theropod dinosaurs.

    PubMed

    Lautenschlager, Stephan; Witmer, Lawrence M; Altangerel, Perle; Rayfield, Emily J

    2013-12-17

    Maniraptoriformes, the speciose group of derived theropod dinosaurs that ultimately gave rise to modern birds, display a diverse and remarkable suite of skeletal adaptations. Apart from the evolution of flight, a large-scale change in dietary behavior appears to have been one of the main triggers for specializations in the bauplan of these derived theropods. Among the different skeletal specializations, partial or even complete edentulism and the development of keratinous beaks form a recurring and persistent trend in from the evolution of derived nonavian dinosaurs. Therizinosauria is an enigmatic maniraptoriform clade, whose members display these and other osteological characters thought to be correlated with the shift from carnivory to herbivory. This makes therizinosaurians prime candidates to assess the functional significance of these morphological characters. Based on a highly detailed biomechanical model of Erlikosaurus andrewsi, a therizinosaurid from the Upper Cretaceous of Mongolia, different morphological configurations incorporating soft-tissue structures, such as a keratinous rhamphotheca, are evaluated for their biomechanical performance. Our results indicate that the development of beaks and the presence of a keratinous rhamphotheca would have helped to dissipate stress and strain, making the rostral part of the skull less susceptible to bending and displacement, and this benefit may extend to other vertebrate clades that possess rhamphothecae. Keratinous beaks, paralleled by edentulism, thus represent an evolutionary innovation developed early in derived theropods to enhance cranial stability, distinct to postulated mass-saving benefits associated with the origin of flight.

  1. Implant-supported overdenture with prefabricated bar attachment system in mandibular edentulous patient

    PubMed Central

    Ha, Seung-Ryong; Song, Seung-Il; Hong, Seong-Tae; Kim, Gy-Young

    2012-01-01

    Implant-supported overdenture is a reliable treatment option for the patients with edentulous mandible when they have difficulty in using complete dentures. Several options have been used for implant-supported overdenture attachments. Among these, bar attachment system has greater retention and better maintainability than others. SFI-Bar® is prefabricated and can be adjustable at chairside. Therefore, laboratory procedures such as soldering and welding are unnecessary, which leads to fewer errors and lower costs. A 67-year-old female patient presented, complaining of mobility of lower anterior teeth with old denture. She had been wearing complete denture in the maxilla and removable partial denture in the mandible with severe bone loss. After extracting the teeth, two implants were placed in front of mental foramen, and SFI-Bar® was connected. A tube bar was seated to two adapters through large ball joints and fixation screws, connecting each implant. The length of the tube bar was adjusted according to inter-implant distance. Then, a female part was attached to the bar beneath the new denture. This clinical report describes two-implant-supported overdenture using the SFI-Bar® system in a mandibular edentulous patient. PMID:23236580

  2. Edentulism, beaks, and biomechanical innovations in the evolution of theropod dinosaurs

    PubMed Central

    Lautenschlager, Stephan; Witmer, Lawrence M.; Altangerel, Perle; Rayfield, Emily J.

    2013-01-01

    Maniraptoriformes, the speciose group of derived theropod dinosaurs that ultimately gave rise to modern birds, display a diverse and remarkable suite of skeletal adaptations. Apart from the evolution of flight, a large-scale change in dietary behavior appears to have been one of the main triggers for specializations in the bauplan of these derived theropods. Among the different skeletal specializations, partial or even complete edentulism and the development of keratinous beaks form a recurring and persistent trend in from the evolution of derived nonavian dinosaurs. Therizinosauria is an enigmatic maniraptoriform clade, whose members display these and other osteological characters thought to be correlated with the shift from carnivory to herbivory. This makes therizinosaurians prime candidates to assess the functional significance of these morphological characters. Based on a highly detailed biomechanical model of Erlikosaurus andrewsi, a therizinosaurid from the Upper Cretaceous of Mongolia, different morphological configurations incorporating soft-tissue structures, such as a keratinous rhamphotheca, are evaluated for their biomechanical performance. Our results indicate that the development of beaks and the presence of a keratinous rhamphotheca would have helped to dissipate stress and strain, making the rostral part of the skull less susceptible to bending and displacement, and this benefit may extend to other vertebrate clades that possess rhamphothecae. Keratinous beaks, paralleled by edentulism, thus represent an evolutionary innovation developed early in derived theropods to enhance cranial stability, distinct to postulated mass-saving benefits associated with the origin of flight. PMID:24297877

  3. Presence of Serum Ferritin before and after Bariatric Surgery: Analysis in Dentate and Edentulous Patients

    PubMed Central

    Mosquim, Victor; Sales Peres, Matheus de Carvalho; Ceneviva, Reginaldo; Chaim, Elinton Adami

    2016-01-01

    Society has changed its own lifestyle, specially its eating habits and physical activities, leading to excessive weight and a sedentary behavior, which has contributed to obesity increase. Bariatric surgery is the most effective treatment to obesity, allowing weight loss and its maintenance. However, it has been related high levels of iron deficiency after surgery. A person’s nutritional status might be affected by total or partial tooth loss. The aim of this longitudinal prospective cohort study was to evaluate the levels of serum ferritin before and after bariatric surgery and to identify if there is a relation with tooth loss. The sample was composed of 50 patients selected and assisted at Amaral Carvalho Hospital, located in Jaú city, Brazil. The use and necessity of prosthesis, dental absence or presence, and serum ferritin dosage were evaluated. Student’s t test, Univariate analysis, Chi-square and Odds Ratio were adopted (p<0.05). There was no significant difference regarding the serum ferritin levels between dentate and edentulous patients prior to surgery (p = 0.436). After surgery, the serum ferritin levels were higher in edentulous patients (prosthesis users) when compared to the pre-surgical levels, and the post-surgical levels presented significant difference regarding the dentate patients (p = 0.024). It can be concluded that rehabilitated patients in postoperative period showed better levels of serum ferritin after surgical intervention. PMID:27695053

  4. Clasping system with rotational path of insertion. 2. Relation between mesio-distal distance of edentulous space and retentive force.

    PubMed

    Yamaga, T; Uji, M; Chikagawa, W; Nokubi, T; Okuno, Y

    1990-12-01

    The rotational path of insertion differs substantially from the conventional path or perpendicular path of insertion. With a rotational path, one segment of the partial denture is seated first, then the remainder of it is rotated into position. One segment of this system is the rigid retentive component with a long occlusal rest and the other is the conventional clasp. This study examined the influence of mesio-distal distance of the edentulous space, the point of the displacing force, the undercut of rigid retentive component and the inclination of the abutment tooth on the retention of this system. The following results were obtained: 1) Retention of the denture was the lowest when a displacing force was applied at the conventional clasp part under the conditions of mesio-distal distances with edentulous spaces of 10, 20 and 30 mm, respectively. 3) Retention showed a tendency to decrease progressively as the proximal undercut on the rigid retentive component was changed to 2.0, 1.5, 1.0 and 0.5 mm, respectively. The values of the decreasing ratio of retentive forces were almost the same regardless of the mesio-distal distance of the edentulous space. 4) Retention of the denture was improved when a tilted tooth was used as an abutment tooth on the rigid retentive component side.

  5. Neuromuscular interaction of jaw and neck muscles during jaw clenching.

    PubMed

    Giannakopoulos, Nikolaos Nikitas; Hellmann, Daniel; Schmitter, Marc; Krüger, Bastian; Hauser, Thomas; Schindler, Hans J

    2013-01-01

    To test the hypothesis that jaw muscles and specific neck muscles, ie, levator scapulae, trapezius, sternocleidomastoideus, and splenius capitis, co-contract at the different submaximum bite forces usually generated during jaw clenching and tooth grinding, and for different bite force directions. Bite-force transducers that measured all three spatial force components were incorporated in 11 healthy subjects. The test persons developed feedback-controlled submaximum bite forces in a variety of bite-force directions. The electromyographic (EMG) activity of the levator scapulae, splenius capitis, and trapezius muscles was recorded, at the level of the fifth cervical vertebra, by use of intramuscular wire electrodes. The activity of the sternocleidomastoideus and masseter muscles was recorded by surface electrodes. For normalization of the EMG data, maximum-effort tasks of the neck muscles were conducted in eight different loading directions by means of a special force-transducer system. Differences between neck-muscle activity during chewing, maximum biting in intercuspation, and the force-controlled motor tasks were compared with the baseline activity of the various muscles by one-way repeated-measures analysis of variance. The results confirmed the hypothesis. Co-contractions of the neck muscles in the range of 3% to 10% of maximum voluntary contraction were observed. Significant (P < .05) activity differences were recorded as a result of the different force levels and force directions exerted by the jaw muscles. Long-lasting action potential trains of single motor units triggered by jaw clenching tasks were also detected. The findings support the assumption of a relationship between jaw clenching and the neck muscle activity investigated. The low level of co-contraction activity, however, requires further study to elucidate possible pathophysiological interactions at the level of single motor units.

  6. Functional Morphology of Eunicidan (Polychaeta) Jaws

    NASA Astrophysics Data System (ADS)

    Clemo, W. C.; Dorgan, K. M.

    2016-02-01

    Polychaetes exhibit diverse feeding strategies and diets, with some species possessing hardened teeth or jaws of varying complexity. Species in the order Eunicida have complex, rigidly articulated jaws consisting of multiple pairs of maxillae and a pair of mandibles. While all Eunicida possess this general jaw structure, a number of characteristics of the jaw parts vary considerably among families. These differences, described for fossilized and extant species' jaws, were used to infer evolutionary relationships, but current phylogeny shows that jaw structures that are similar among several families are convergent. Little has been done, however, to relate jaw functional morphology and feeding behavior to diet. To explore these relationships, we compared the jaw kinematics of two taxa with similar but evolutionarily convergent jaw structures: Diopatra (Onuphidae) and Lumbrineris (Lumbrineridae). Diopatra species are tube-dwelling and predominantly herbivorous, whereas Lumbrineris species are burrowing carnivores. Jaw kinematics were observed and analyzed by filming individuals biting or feeding and tracking tooth movements in videos. Differences in jaw structure and kinematics between Diopatra and Lumbrineris can be interpreted to be consistent with their differences in diet. Relating jaw morphology to diet would provide insight into early annelid communities by linking fossil teeth (scolecodonts) to the ecological roles of extant species with similar morphologies.

  7. Will wearing dentures affect edentulous patients' breathing during sleep?

    PubMed

    Chen, Qiuwen; Zou, Dong; Feng, Hailan; Pan, Shaoxia

    2017-01-14

    The purpose of this study is to investigate the effect of wearing dentures on obstructive sleep apnea and hypopnea among completely edentulous patients. A self-controlled study was conducted among 30 edentulous patients. Polysomnograms were recorded in the sleep laboratory on two consecutive nights. Participants slept with their dentures in one night and without dentures in the other. The apnea and hypopnea index (AHI), lowest oxygen saturation (L-SpO2), and morning blood pressure (MBP) were collected for statistical analysis. Among the edentulous participants, 24 showed a higher AHI when sleeping with dentures. The average AHI for all 30 participants was significantly higher when they slept with dentures than without dentures (16.3 ± 14.7 vs 13.4 ± 14.0/h, P < 0.05). Participants in the non-obstructive sleep apnea-hypopnea syndrome (non-OSAHS) subgroup (AHI <5 when sleeping without dentures) had a significant increase in AHI when sleeping with dentures, and nearly half of them (5 out of 11) reached the diagnostic standard for OSAHS (AHI >5). A higher morning diastolic blood pressure was recorded when participants slept with dentures (P < 0.05), while no significant difference was found in the L-SpO2 score and morning systolic blood pressure. Wearing dentures can lead to significant increase of AHI and diastolic MBP among edentulous people. Hence, we suggest that Chinese edentulous people should remove their dentures before sleep. ChiCTR-IOR-16008404.

  8. Marcus Gunn jaw-winking phenomenon: a new supplemental test in the preoperative evaluation.

    PubMed

    Wong, J F; Thériault, J F; Bouzouaya, C; Codère, F

    2001-11-01

    To introduce a new method for the evaluation of Marcus Gunn jaw-winking ptosis that more precisely defines the severity of blepharoptosis. A retrospective review of 16 consecutive patients with Marcus Gunn jaw-winking ptosis presenting to our institution between 1993 to 1999 was performed. The position of the affected eyelid was observed after applying a technique of jaw immobilization and disruption of fusion with temporary occlusion of the ipsilateral side. In patients presenting with mild to moderate Marcus Gunn jaw-winking, the majority (62.5%) demonstrated a positive test, uncovering complete or near complete ptosis. Test results were partially positive in 3 patients (18.8%) with increased but not complete ptosis and negative in 3 patients (18.8%) with no change in eyelid position. Blepharoptosis associated with Marcus Gunn jaw-winking phenomenon is often more severe than found by conventional clinical evaluation. This finding may explain the frequent undercorrection and unpredictable results following levator resection. In patients exhibiting a positive jaw-winking ptosis test, disappointing outcomes with levator resection may be avoided by instead proceeding with a frontalis suspension with levator disinsertion as recommended for ptosis with severe jaw winking.

  9. The Impact of Edentulism on Oral and General Health

    PubMed Central

    Emami, Elham; de Souza, Raphael Freitas; Kabawat, Marla; Feine, Jocelyne S.

    2013-01-01

    An adequate dentition is of importance for well-being and life quality. Despite advances in preventive dentistry, edentulism is still a major public health problem worldwide. In this narrative review, we provide a perspective on the pathways that link oral to general health. A better understanding of disease indicators is necessary for establishing a solid strategy through an organized oral health care system to prevent and treat this morbid chronic condition. PMID:23737789

  10. Horizontal alveolar ridge distraction in an edentulous patient.

    PubMed

    Laster, Zvi; Reem, Younis; Nagler, Rafael

    2011-02-01

    Full fixed dental rehabilitation, including attachment based over denture (to dental implants) is the optimal solution for edentulous patients, although the insertion of implants will be impossible when the alveolar ridge has been horizontally and severely absorbed. A full arch narrow ("knife-edge") alveolar crest creates a "borderline" condition. Dental implants cannot be inserted into a narrow ridge, which is also at risk of rapid absorption, especially under the pressure of a full denture. Current clinical solutions have been limited. In bone augmentation, the bone absorption rate has been approximately 50%, requiring 6-month therapy prolongation for the grafted bone to consolidate. We have described an edentulous patient whose "knife-edge" maxillary alveolar crest was widened with crest expanders (horizontal distractors). Only 6 weeks after initiation of the distraction, a wide enough ridge had been created, allowing bilateral insertion of implants, followed by attachment-based full dental rehabilitation. Bone augmentation was avoided, and the implants were placed in the correct lateral position, with sufficient attached gingiva obtained. Horizontal crest expanding in narrow-alveolar edentulous patients can significantly reduce both morbidity and the therapeutic period and substantially increase the therapeutic success rate, based on both soft tissue and bone distraction. With this technique, our patient was without the denture for only 6 weeks. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Reconstruction of severe atrophic jaws with Fresh Frized Bone Allografts: clinical histologic and histomorphometric evaluation.

    PubMed

    Boniello, R; Gasparini, G; D'Amato, G; Torroni, A; Marianetti, T M; Foresta, E; Azzuni, C; Cervelli, D; Pelo, S

    2013-05-01

    Rehabilitation of maxillary edentulism with implant-supported prostheses has come into common clinical practice. Although autologous bone has osteoinductive, osteoconductive and osteogenetic properties, its use is subject to certain disadvantages such as: Increased morbidity Limited amount of bone harvested from each donor site. The aim of this study is to analyze clinical, histological and histomorphometric results of homologous bone for implantoprosthetic rehabilitation in severe atrophic jaws. Twenty consecutive patients, 14 female and 6 males, were treated with homologous bone bank. Treatment protocol consist of: first surgycal step, trasversal and vertical volume restore, second surgycal step: screw remove, specimen biopsy and insert implant fixtures. Data show that Fresh Frozen Bone Allografts (FFBA) could be a valuable substitute for autologous bone, in as much as histological and histomorphometric results are widely overlapping. Homologous bone is a valuable option for its large availability with a low cost, good versatility, no morbidity at the donor site, shorter surgical time and hospital stay.

  12. The effect of different prosthetic restorations on the dietary selection in edentulous patients. A longitudinal study of patients initially treated with optimal complete dentures and finally with tissue-integrated prostheses.

    PubMed

    Sandström, B; Lindquist, L W

    1987-12-01

    The effect of prosthetic restoration of masticatory ability on dietary selection was evaluated in 23 edentulous patients with denture adaptation problems. The patients were first given optimal complete dentures and then a fixed prosthesis on tissue-integrated implants in the lower jaw. Changes in dietary selection were evaluated from 4-day records obtained before prosthetic treatment and on six occasions up to 78 months after treatment. With the method used, no significant changes in food selection were recorded during the rehabilitation period, except for a slight increase in intake of crisp bread and fresh fruit after treatment with fixed tissue-integrated prostheses in the mandibular jaw. It is concluded that an improved oral function will not in itself lead to a change in dietary selection and that dietary changes probably require professional and individually given dietary advice by a trained dietitian.

  13. Asymmetric Requirement of Surface Epithelial β-Catenin During the Upper and Lower Jaw Development

    PubMed Central

    Sun, Ye; Teng, Ian; Huo, Randi; Rosenfeld, Michael G; Olson, Lorin E; Li, Xiaokun; Li, Xue

    2012-01-01

    Background: Intercellular communication between epithelial and mesenchymal cells is central to mammalian craniofacial development. β-catenin is the gateway of canonical Wnt signaling, one of the major evolutionarily conserved cell–cell communication pathways in metazoa. In this study, we report an unexpected stage- and tissue-specific function of β-catenin during mammalian jaw development. Results: Using a unique mouse genetic tool, we have discovered that epithelial β-catenin is essential for lower jaw formation, while attenuation of β-catenin is required for proper upper jaw development. Changes in β-catenin in vivo alter major epithelial Fgf8, Bmp4, Shh, and Edn1 signals, resulting in partial transcriptional reprogramming of the neural crest-derived mesenchyme, the primary source of jawbones. Conclusions: The Wnt/β-catenin signal coordinates expression of multiple epithelial signals and has stage-specific asymmetric functions during mammalian upper and lower jaw development. In addition, these findings suggest that evolutionary changes of the canonical Wnt/β-catenin signaling pathway may lead to innovation of jaws. Developmental Dynamics 241:663–674, 2012. © 2012 Wiley Periodicals, Inc. Key Findings Mammalian epithelial Wnt/β-catenin signaling has asymetric functions in the upper and lower jaw development. The canonical Wnt/β-catenin pathway coordinates expression of multiple epithelial signals including Fgf8, Bmp4, Shh, and Edn1. Activation of epithelial Wnt/β-catenin signaling induces molecular transformation of the upper jaw to the lower jaw mesenchymal phenotype. Evolutionary changes of the canonical Wnt/β-catenin signaling pathway may lead to innovation of jaws. PMID:22354888

  14. Functional impression and jaw registration: a single session procedure for the construction of complete dentures.

    PubMed

    Utz, K-H; Müller, F; Kettner, N; Reppert, G; Koeck, B

    2004-06-01

    The conventional fabrication of complete dentures involves two separate clinical sessions for functional impression making and jaw registration. The presented method combines both procedures in one session. The aim of this study was to survey the three-dimensional tooth positions in complete dentures with reference to the ridges to establish arbitrary guideline values that could be used for the manufacturing of tooth-position analogue plastic rims on functional impression trays. New complete dentures were fabricated by supervised undergraduate students in the conventional manner for 104 edentulous patients. The position of the maxillary teeth was surveyed in the horizontal plane using the Schmuth 'vizor-measuring plate'. The vertical dimension of occlusion, represented as the distance between opposing ridge areas of the dentures in maximum intercuspation, was measured at different sites by means of a Gutowski gauge. The tooth positions on the dentures varied widely, e.g. the horizontal distances between the incisive papilla and the maxillary incisors was 7.1 +/- 2.3 (3-14) mm. The vertical dimension of occlusion, which is most important in the jaw registration, varied equally with an anterior inter-alveolar distance between 12 and 33 (20.4 +/- 4.0) mm. Arbitrary moulding of the tooth position-analogue plastic rims does not seems to be an ideal method of pre-shaping functional impression trays, because the individual anatomical variation is considerable. Alternatively, the horizontal and vertical tooth positions of functionally and aesthetically pleasing dentures should be measured to pre-shape the rims of functional impression trays in the maxillary and the mandibular jaw. Such trays are a valuable tool for functional impressions and an immediate preliminary jaw registration in the fabrication of new complete dentures. This method allows a first try-in of the full set-up in the third clinical visit without loosing precision.

  15. 21 CFR 872.2060 - Jaw tracking device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Jaw tracking device. 872.2060 Section 872.2060...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.2060 Jaw tracking device. (a) Jaw tracking device for monitoring mandibular jaw positions relative to the maxilla—(1) Identification. A jaw tracking...

  16. 21 CFR 872.2060 - Jaw tracking device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Jaw tracking device. 872.2060 Section 872.2060...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.2060 Jaw tracking device. (a) Jaw tracking device for monitoring mandibular jaw positions relative to the maxilla—(1) Identification. A jaw tracking...

  17. Focal dystonia of the jaw and the differential diagnosis of unilateral jaw and masticatory spasm.

    PubMed Central

    Thompson, P D; Obeso, J A; Delgado, G; Gallego, J; Marsden, C D

    1986-01-01

    The clinical features, differential diagnosis and treatment of unilateral spasms of the jaw and masticatory muscles are discussed and illustrated by eight cases of unilateral jaw spasms of various aetiologies. These include focal dystonia of the jaw, hemimasticatory spasm with and without facial hemiatrophy, paroxysmal events in multiple sclerosis and tetany. Attention is particularly drawn to four cases of unilateral dystonia of the jaw which has not been described before. Images PMID:3734821

  18. Bone Height Changes of the Mandibular Edentulous Ridge in Screw Retained Versus Telescopic Restorations for Completely Edentulous Patients

    PubMed Central

    Helal, Eman; El-Zawahry, Mohamed; Gouda, Ayman; Elkhadem, Amr Hosny; Ibrahim, Samira Ibrahim

    2017-01-01

    AIM: This study was established to evaluate the amount of bone height changes in the posterior mandibular area of edentulous patients receiving screw-retained prostheses versus removable telescopic implant overdentures. MATERIAL AND METHODS: Every patient received four inter-foraminal implants regarding the mandibular arch and four anterior implants for the maxillary arch, computer guided surgical guides were planned for the insertion of the implants accurately with a flapless technique. Panoramic radiographs were made immediately, six months and twelve months after the prostheses` use proportional area and vertical measurements were applied to determine changes in the bone height of the posterior mandibular edentulous area. RESULTS: After twelve months, a statistically non-significant amount of bone resorption was reported for both groups. CONCLUSION: Up to the limitations of this study both treatment options the screw retained and telescopic overdenture can be used for rehabilitation of completely edentulous patients. These cases must be followed for a longer period to have a definite answer regarding their efficiency in the long run. PMID:28293321

  19. Self-aligning lathe chuck jaws

    DOEpatents

    Not Available

    1980-08-26

    A lathe chuck jaw for a lathe chuck having a radially moving actuator which radially moves the jaw into and out from the workpiece is described. A jaw base part is rigidly connected to the actuator. A jaw shoe part is rotatably attached to the base part. The shoe part has a workpiece-conforming surface which can hold the workpiece. The rotatable attachment of the shoe part allows it to match the general orientation of the workpiece, including a nonlongitudinal orientation due to a workpiece's imperfect shape.

  20. Self-aligning lathe chuck jaws

    SciTech Connect

    Peterson, William R.

    1982-01-01

    A lathe chuck jaw for a lathe chuck having a radially moving actuator which radially moves the jaw in to and out from the workpiece. A jaw base part is rigidly connected to the actuator. A jaw shoe part is rotatably attached to the base part. The shoe part has a workpiece-comforming surface which can hold the workpiece. The rotatable attachment of the shoe part allows it to match the general orientation of the workpiece, including a nonlongitudinal orientation due to a workpiece's imperfect shape.

  1. Self-aligning lathe chuck jaws

    SciTech Connect

    Peterson, W.R.

    1982-10-12

    A lathe chuck jaw for a lathe chuck having a radially moving actuator which radially moves the jaw in to and out from the workpiece. A jaw base part is rigidly connected to the actuator. A jaw shoe part is rotatably attached to the base part. The shoe part has a workpiece-comforming surface which can hold the workpiece. The rotatable attachment of the shoe part allows it to match the general orientation of the workpiece, including a nonlongitudinal orientation due to a workpiece's imperfect shape.

  2. Osteonecrosis of the jaw due to bisphosphonates.

    PubMed

    2008-10-01

    Bisphosphonates are widely used to treat osteoporosis, bone complications of cancer, malignant hypercalcaemia and Paget's disease. Osteonecrosis of the jaw is a major adverse effect of these drugs. It can affect eating, interpersonal relations, and physical appearance. Ulceration of the tongue and nerve involvement can also occur. Osteonecrosis of the jaw due to bisphosphonates is mainly seen in cancer patients, and more rarely in patients treated for osteoporosis. Between 5% and 11% of cancer patients treated with bisphosphonates develop osteonecrosis of the jaw. The frequency of jaw osteonecrosis increases with the duration of bisphosphonate treatment and is higher in case of recent dental work. The main bisphosphonate withdrawal and surgery are rarely effective. In practice, when bisphosphonate therapy is needed, the patient must be informed of the risks, should seek dental care (if possible) before starting treatment, see a dentist regularly, and consult a doctor in case of delayed healing after dental extraction, jaw pain, or numbness.

  3. [Method of functional impression receiving for edentulous patients].

    PubMed

    Zhulev, E N; Manakov, A L

    2007-01-01

    150 edentulous patients (78 men and 72 women) aged from 34 to 86 were examined and prosthodontically treated according to improved method. The method of taking preliminary and final mucodynamic impressions was suggested. Contractive activity of muscle groups related to the surrounding tissues was studied in comparison with the method of F. Gerbst. Optoelectronic method was used to study 3-dimensional virtual models of gypsum casts poured from impressions made both in accordance to the regular and improved methods. Better fixation of complete dentures followed getting impressions with the help of improved method was achieved.

  4. Prosthetic rehabilitation of edentulism prevents malnutrition in nursing home residents.

    PubMed

    Andreas Zenthöfer, Andreas; Rammelsberg, Peter; Cabrera, Tomas; Hassel, Alexander

    2015-01-01

    To investigate the association between prosthetic rehabilitation and malnutrition in institutionalized elders, 255 nursing home residents were recruited for this study and underwent a comprehensive dental examination. The body mass index (BMI) was administered to estimate the nutritional condition. Participants with BMI < 20 kg/mc were categorized as malnourished (n = 33), whereas all others were categorized as adequately nourished (n = 222). The number of teeth present and the prevalence of prosthetic rehabilitation were significantly lower in malnourished participants (P < .05). Malnutrition risk was 4.6 times higher for participants who were edentulous and did not wear dentures. Adequate replacement of teeth is important to prevent malnutrition in institutionalized older people.

  5. Prosthetic rehabilitation of edentulous mandibulectomy patient: a clinical report.

    PubMed

    Prakash, Vijay

    2008-01-01

    Segmental resection of the mandible commonly results in deviation of the mandible to the defective side. The amount of deviation depends on the amount of hard and soft tissue involvement, the method of surgical site closure, the degree of impaired tongue function, the number of remaining teeth and the extent of loss of sensory and motor innervations. Prosthodontic treatment along with physical therapy may be useful in reducing mandibular deviation and improving masticatory efficiency. This clinical report describes the use of two rows of nonanatomic teeth on the unresected side. This provided a broader occlusal table and improved masticatory efficiency in our edentulous madibulectomy patient.

  6. Histomorphometric analysis of implant anchorage for 3 types of dental implants following 6 months of healing in baboon jaws.

    PubMed

    Carr, A B; Gerard, D A; Larsen, P E

    2000-01-01

    In an effort to better understand the supporting anatomy for unloaded endosseous dental implants, this study focused on the histomorphometric analysis of 3 different types of implants placed into non-human primate jaws and allowed to heal for 6 months. This report describes data from 24 screw-type dental implants placed in edentulated (2 months healing time) posterior arches of 4 adult female baboons. Three different implants were placed and allowed to heal for 6 months prior to processing for evaluation: commercially pure titanium (n = 8), titanium alloy (n = 8), and titanium plasma-sprayed (n = 8). Circumferential bone-implant interface sampling from 6 regions along the entire length of each implant was obtained for evaluation of percent bone-implant contact (%BIC) and percent bone area (%BA), within 3 mm of the implant. Data were collected (reliability of 1.6% for both parameters) and analyzed by an observer blinded to implant material using IMAGE analysis software for differences between jaws, implant biomaterials, and jaw/biomaterial (analysis of variance, pairwise comparison using least squares method with Bonferroni adjustment). The results indicated that the overall mean %BIC was 55.8 and mean %BA was 48.1. Maxillary and mandibular differences for both parameters were statistically significantly different: %BIC in maxilla 50.8, in mandible 60.8; %BA in maxilla 43.6, in mandible 52.6 (both significant at the P < .05 level). The biomaterial analyses revealed no significant differences between the different implants for %BIC or %BA. The trend observed--that mandibular values were greater than maxillary values for the overall jaw comparisons--was found to be consistent at the jaw/biomaterial level, although the small sample size limited statistical power. These data, along with data from a previous 3-month study, provide insight into baseline supporting anatomy for dental implants.

  7. Surgical and prosthetic rehabilitation of edentulous adult cleft palate patients by dental implants.

    PubMed

    Güven, Orhan; Gürbüz, Ayhan; Baltali, Evre; Yilmaz, Burak; Hatipoğlu, Murat

    2010-09-01

    Adult patients who did not receive proper treatment for cleft palate are challenging for clinicians in terms of prosthetic rehabilitation. Moreover, during the late stages of adulthood when patients become edentulous, prosthetic reconstruction becomes even more challenging. This clinical report describes the prosthetic rehabilitation of 2 edentulous geriatric patients with unrepaired cleft palate by placement of dental implants after closure of the oronasal communications.

  8. A 2-year report on maxillary and mandibular fixed partial dentures supported by Astra Tech dental implants. A comparison of 2 implants with different surface textures.

    PubMed

    Karlsson, U; Gotfredsen, K; Olsson, C

    1998-08-01

    In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO-blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100% (TiO-blasted) vs 95.3% (machined), P = 0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 types of implant after 2 years of loading, 0.04 (0.82) mm, P > 0.30.

  9. Design variations of the rotational path removable partial denture.

    PubMed

    Schwartz, R S; Murchison, D G

    1987-09-01

    The rotational path removable partial denture is a convenient design to use when restoring anterior edentulous spaces and can produce excellent esthetic results. In situations that are not ideal for the conventional rotational path, design alterations can be made that will allow the same excellent results to be achieved.

  10. Assessment of bone mineral density in the jaws and its relationship to radiomorphometric indices

    PubMed Central

    Gulsahi, A; Paksoy, CS; Ozden, S; Kucuk, NO; Cebeci, ARI; Genc, Y

    2010-01-01

    Objectives The aim of this study was to evaluate maxillary, mandibular and femoral neck bone mineral density using dual energy X-ray absorptiometry (DXA) and to determine any correlation between the bone mineral density of the jaws and panoramic radiomorphometric indices. Methods 49 edentulous patients (18 males and 31 females) aged between 41 and 78 years (mean age 60.2 ± 11.04) were examined by panoramic radiography. Bone mineral density (BMD) of the jaws and femoral neck was measured with a DXA; bone mineral density was calculated at the anterior, premolar and molar regions of the maxilla and mandible. Results The mean maxillary molar BMD (0.45 g cm−2) was significantly greater than the maxillary anterior and premolar BMD (0.31 g cm−2, P < 0.05). Furthermore, the mean mandibular anterior and premolar BMD (1.39 g cm−2 and 1.28 g cm−2, respectively) was significantly greater than the mean mandibular molar BMD (1.09 g cm−2, P < 0.01). Although BMD in the maxillary anterior and premolar regions were correlated, BMD in all the mandibular regions were highly correlated. Maxillary and mandibular BMD were not correlated with femoral BMD. In addition, mandibular cortical index (MCI) classification, mental index (MI) or panoramic mandibular index (PMI) values were not significantly correlated with the maxillary and mandibular BMDs (P > 0.05). Conclusions The BMD in this study was highest in the mandibular anterior region and lowest in the maxillary anterior and premolar regions. The BMD of the jaws was not correlated with either femoral BMD or panoramic radiomorphometric indices. PMID:20587652

  11. Swiveling Lathe Jaw Concept for Holding Irregular Pieces

    NASA Technical Reports Server (NTRS)

    David, J.

    1966-01-01

    Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.

  12. Evaluation of the effect of the residual bone angulation on implant-supported fixed prosthesis in mandibular posterior edentulism. Part II: 3-D finite element stress analysis.

    PubMed

    Akça, K; Iplikçioğlu, H

    2001-01-01

    Buccolingual angulation of the mandibular posterior edentulous region may affect the prosthetic load conditions, so as to cause high stress concentrated areas that may easily lead to failure. The aim of this study was to evaluate the effect of various predetermined buccolingual angulation values on stress distribution in the mandibular posterior edentulous region restored with implant-supported fixed partial dentures, using three-dimensional finite element analysis. Stress analyses were performed applying 400N oblique force to implant-supported fixed prosthesis. Stress analyses indicated tensile stress values on the buccal surface and compressive stress values on the lingual surface of cortical bone were increased as the angulation of the edentulous bone increased (especially corresponding to the cervical region of the implants). Compressive stress values, observed where two implants were placed at the second premolar and second molar regions (5-7 design) and first and second molar regions (6-7 design), respectively, were very close to or even exceeded the ultimate compressive strength of bone. It is concluded that when a definite buccolingual angulation is added to other existing risk factors such as bruxism, placing an implant for every missing tooth might reduce the high stress concentration areas.

  13. Jaw movement alters the reaction of human jaw muscles to incisor stimulation.

    PubMed

    Brinkworth, Russell S A; Türker, Kemal S

    2005-07-01

    The changes in the minimum time to consciously react (reaction time) and the order of jaw muscle recruitment to precisely controlled axial stimulation of the incisors during controlled jaw movements are not known. To this end, ten subjects were recruited to investigate the reaction time of bilateral temporalis and masseter muscles and bite force. Stimuli were delivered axially to the upper central incisors during active jaw closing and opening, and under static conditions. The results showed that the reaction time was increased an average of 35% during both jaw opening and closing movements when compared with static jaw conditions. The left temporalis was recruited approximately 10 ms before the right temporalis, whereas no significant side differences were found between the masseter muscles. The masseter muscles were recruited an average of 20 ms before the temporalis muscles during jaw closing, but no difference existed during opening. Under static conditions the reaction time in the bite force was approximately 16 ms longer than the left temporalis, but was not significantly different from the reaction time of any of the other muscles, indicating that, under the static conditions tested, the left temporalis was more often responsible for initiation of the mechanical reactions in the jaw. Because of active compensation, no force measurements were made during jaw movement. This study is a prerequisite for investigations into the modulation of reflexes during jaw movement, because a response to a stimulus commencing after the minimum reaction time may not be entirely reflex in origin.

  14. Digital versus conventional implant impressions for edentulous patients: accuracy outcomes.

    PubMed

    Papaspyridakos, Panos; Gallucci, German O; Chen, Chun-Jung; Hanssen, Stijn; Naert, Ignace; Vandenberghe, Bart

    2016-04-01

    To compare the accuracy of digital and conventional impression techniques for completely edentulous patients and to determine the effect of different variables on the accuracy outcomes. A stone cast of an edentulous mandible with five implants was fabricated to serve as master cast (control) for both implant- and abutment-level impressions. Digital impressions (n = 10) were taken with an intraoral optical scanner (TRIOS, 3shape, Denmark) after connecting polymer scan bodies. For the conventional polyether impressions of the master cast, a splinted and a non-splinted technique were used for implant-level and abutment-level impressions (4 cast groups, n = 10 each). Master casts and conventional impression casts were digitized with an extraoral high-resolution scanner (IScan D103i, Imetric, Courgenay, Switzerland) to obtain digital volumes. Standard tessellation language (STL) datasets from the five groups of digital and conventional impressions were superimposed with the STL dataset from the master cast to assess the 3D (global) deviations. To compare the master cast with digital and conventional impressions at the implant level, analysis of variance (ANOVA) and Scheffe's post hoc test was used, while Wilcoxon's rank-sum test was used for testing the difference between abutment-level conventional impressions. Significant 3D deviations (P < 0.001) were found between Group II (non-splinted, implant level) and control. No significant differences were found between Groups I (splinted, implant level), III (digital, implant level), IV (splinted, abutment level), and V (non-splinted, abutment level) compared with the control. Implant angulation up to 15° did not affect the 3D accuracy of implant impressions (P > 0.001). Digital implant impressions are as accurate as conventional implant impressions. The splinted, implant-level impression technique is more accurate than the non-splinted one for completely edentulous patients, whereas there was no difference in the accuracy

  15. A Geometric Classification of Jaw Deformities

    PubMed Central

    Gateno, Jaime; Alfi, David; Xia, James J.; Teichgraeber, John F.

    2015-01-01

    In the United States, the most widely used classification system for jaw deformities is the one provided by the International Classification of Diseases, Clinical Modification (ICD-CM), a taxonomy scheme that is based on the World Health Organization's International Classification of Diseases (ICD). The last iteration of ICD-CM, version 10, sorts jaw deformities according to geometry, into 3 groups: anomalies of jaw size, anomalies of jaw-cranial base relationship, or unspecified. Yet these deformities can affect 6 different geometric attributes: size, position, orientation, shape, symmetry, and completeness. In clinical practice and in teaching we have found the ICD-CM classification to be incomplete and disjointed. With this in mind, we have developed a better classification system. The purpose of this paper is to present it. PMID:26608152

  16. Wire-free fixation of jaw fractures.

    PubMed

    Cousin, G C S

    2009-10-01

    Stainless steel wire is often used in the management of jaw fractures to provide intraoperative or postoperative intermaxillary fixation (IMF). Wiring of the jaws is time-consuming, a second procedure is needed to remove it, and needlestick injuries occur during placement. We report on 151 consecutive patients who had wire-free fixation of jaw fractures, and outline the value of a system of plastic anchorage points applied to individual teeth in both jaws that allows for wire-free IMF when they are linked by elastics (Rapid IMF, Synthes, PA, USA). A total of 150 successive patients had wire-free fixation of 146 mandibular and 5 maxillary fractures. Ninety-eight were hand-held in occlusion, and 52 were treated using Rapid IMF. There were few complications.

  17. Bisphosphonate-related osteonecrosis of the jaw: the Florence experience

    PubMed Central

    Borgioli, Alberto; Duvina, Marco; Brancato, Leila; Viviani, Christian; Brandi, Maria Luisa; Tonelli, Paolo

    2007-01-01

    Aims. Bisphosphonates (BPs) are important therapeutic drugs in multiple myeloma and cancers with bone metastases. Bisphosphonate-Related Osteonecrosis of the Jaw (BRONJ) has been described as a potential side effect of the last generation BPs. The Authors evaluated clinical features, preventing measures and treatment strategies. Patients and methods. The Authors retrospectively analyzed 19 patients affected by malignant cancer in endovenous treatment with BPs. Fourteen patients were treated with zoledronate, 1 with pamidronate and 4 with both drugs for breast cancer (9 patients), multiple myeloma (6 patients), prostatic cancer (3 patients) and colon cancer (1 patient). Results. The lenght of therapy was 5-36 months before osteonecrosis was observed; in 15 patients BRONJ involved the mandible, in 2 the maxilla and in 2 both jaws. The trigger factors were tooth extractions, inadequate removable total denture, basic and advanced surgery, root canal treatment. Ten patients received non-surgical treatment, 7 patients minor surgical procedures and 2 patients a partial maxillectomy. Healing was achieved in all maxillary localization, and in one mandibular localization with partial maxillectomy. Conclusions. Prevention is the best important phase in the management of this pathology. Risk factors are the type of bisphosphonate and the length of exposure, while dental surgical procedures are trigger factors. Conservative treatment seems to be the best way to control BRONJ, but bone resection and soft tissue closure have to be performed when the lesion is refractory to conservative approach. PMID:22460753

  18. A survey of edentulous individuals in a district in Amsterdam, the Netherlands.

    PubMed

    Swallow, J N; van Groenestijn, M A; Maas-de Waal, C J; Mileman, P A

    1978-07-01

    A survey of a representative adult population of a district in Amsterdam (the Jordaan) revealed an overall edentulousness rate of 23%. Proportionally more females than males wore complete dentures, and the lower socioeconomic group was proportionally better represented in edentate group than were the middle and the higher classes. No significant differences were found in comparisons of the edentulousness rate in the Study group and other investigations in Holland and England and Wales. It is suggested that there might be a relationship between the rate of edentulousness and changes in the amount of freely disposable income.

  19. Missing Teeth and Prosthetic Treatment in Patients Treated at College of Dentistry, University of Dammam

    PubMed Central

    Al-Harbi, Fahad A.; Khan, Soban Q.; Raustia, Aune

    2017-01-01

    The percentage of completely and partially edentulous patients and their prosthetic treatment at the Department of Substitutive Dental Sciences (SDS), College of Dentistry, University of Dammam, were investigated. Panoramic radiographs and medical records of adult patients (n = 479, mean age 45.9 years, and range 25–96 years) treated in 2011–2014 were examined. 6% of the patients were completely edentulous, 8% had single jaw edentulousness, and 74% were partially edentulous. Edentulousness was significantly correlated with age and the number of missing teeth was significantly higher among males (p < 0.026). Diabetes was significantly associated with complete edentulousness, single edentulous jaw (p value 0.015), and partial edentulousness (p value 0.023). Kennedy class III was the most frequent class of partial edentulousness in single and/or both jaws (p = 0.000). Patients having class I and/or class II were treated most often with removable partial dentures (RPD) (p = 0.000), while patients having class III were treated with fixed partial dentures (FPD). It was found that complete edentulousness increases in older age and the number of missing teeth was significantly higher among males. Kennedy class III was most common in both upper and lower jaw and was treated more often with FPD than with RPD. PMID:28828005

  20. Functional jaw muscle assessment in patients with a full fixed prosthesis on a limited number of implants: a review of the literature.

    PubMed

    Dellavia, Claudia; Rosati, Riccardo; Del Fabbro, Massimo; Pellegrini, Gaia

    2014-01-01

    Full fixed prosthesis on a limited number of implants (FFP) are a viable treatment option for edentulous patients with a reduced amount of residual bone. Jaw muscular function in FFP patients has been evaluated in several studies, however heterogeneous data emerge from literature. The aim of this review of the literature was to assess the function of jaw muscles in edentulous patients restored with full fixed prostheses on a limited number (≤ 6) of implants, as compared to dentate subjects and edentulous subjects wearing dentures, implant-supported overdentures or full fixed prostheses supported by more than six implants. An electronic search of databases up to December 2013 was performed. The articles were selected using specific inclusion criteria, independent of the study design. A total of 1598 records were identified. After removing the duplicates and excluding records based on title and abstract, only 37 eligible records were identified. After full-text review, seventeen studies were selected for analysis according to the inclusion criteria. From the included studies, only one evaluated masseter muscle thickness in a cross sectional study by means of ultrasound, while the 16 remaining papers evaluated muscular function by using electromyography (EMG). Those studies analysed several heterogeneous parameters throughout the execution of five functional tests and were therefore described and pooled according to the following task categories: clenching; swallowing; reflex and fatigue for statics; and chewing for dynamics. The results of selected studies seem to indicate that, compared to dentate controls, FFP patients display a global satisfactory neuromuscular equilibrium in static activities, but still have some impairment during chewing.

  1. Removable partial dentures--treatment now and for the future.

    PubMed

    Jones, John D; Turkyilmaz, Ilser; Garcia, Lily T

    2010-04-01

    The use of a removable partial denture (RPD) in clinical practice remains a viable treatment modality. Various advancements have improved the quality of a RPD, subsequently improving the quality of life for the individuals that use them. This article describes four removable partial denture treatment modalities that provide valuable treatment for the partially edentulous patient. These modalities include: the implant supported RPD, attachment use in RPDs, rotational path RPDs, and Titanium and CAD/CAM RPDs. Data on future needs for RPDs indicate that while there is a decline in tooth loss in the U.S., the need for RPDs will actually increase as the population increases and ages. With the growth in the geriatric population, which includes a high percentage of partially edentulous patients, the use of RPDs in clinical treatment will continue to be predictable treatment option in clinical dentistry.

  2. Evaluation by quantitative magnetic resonance imaging of trabecular bone quality in the dentate and edentulous mandible.

    PubMed

    Celenk, Cetin; Celenk, Peruze

    2008-01-01

    To quantify the differences in mandibular trabecular bone quality between edentulous and dentate patients using quantitative magnetic resonance imaging (QMRI). The patients in this study had been referred to our clinic for QMRI examination for various reasons. A total of 40 male patients (18 dentate, 22 edentulous), 45-55 years of age, were examined. Mandibular T2* axial cross-sections were performed following receipt of consent from each patient. T2* relaxation time values (RTVs) were determined in the trabecular area. The mean mandibular T2* RTVs of dentate and edentulous patients were 181 and 182, respectively. There were no significant differences between the two groups (P=0.929) (Student's t-test). Mandibular trabecular bone quality may not be influenced by edentulousness according to QMRI.

  3. Biomechanical considerations on tooth-implant supported fixed partial dentures

    PubMed Central

    Calvani, Pasquale; Hirayama, Hiroshi

    2012-01-01

    This article discusses the connection of teeth to implants, in order to restore partial edentulism. The main problem arising from this connection is tooth intrusion, which can occur in up to 7.3% of the cases. The justification of this complication is being attempted through the perspective of biomechanics of the involved anatomical structures, that is, the periodontal ligament and the bone, as well as that of the teeth- and implant-supported fixed partial dentures. PMID:23255882

  4. Prosthetic rehabilitation of edentulous patient with limited oral access: A clinical report.

    PubMed

    Kumar, Sandeep; Arora, Aman; Yadav, Reena

    2012-07-01

    Microstomia may result from surgical treatment of orofacial neoplasms, cleft lips, maxillofacial trauma, burns, radiotherapy or scleroderma. A maximal oral opening that is smaller than the size of a complete denture can make prosthetic treatment challenging. This clinical report presents the prosthodontic management of a total edentulous patient with microstomia. Sectional mandibular and maxillary trays and foldable mandibular and maxillary denture were fabricated for the total edentulous patient.

  5. [Effects of wearing dentures on sleep breathing among edentulous people: a preliminary study].

    PubMed

    Zou, Dong; Dong, Xiao-song; Han, Fang; Pan, Shao-xia; Feng, Hai-lan

    2014-04-18

    To investigate the effects of wearing dentures on sleep breathing among edentulous people. Nine edentulous people were recruited to participate in this selfcontrolled case series clinical study. Polysomnogram (PSG) was carried out on two consecutive nights, on one night the patients slept wearing dentures, and on the other without dentures. The indexes such as apnea and hypopnea index (AHI), L-SpO2, and morning blood pressure etc. were compared. Among the nine edentulous people, eight showed a higher AHI when they slept with dentures, and only one showed a lower AHI. The average AHI of the nine edentulous people was 8.82 without dentures and 11.72 with dentures, which meant that AHI was significantly higher when the edentulous people slept with dentures in their mouths (P<0.05). While no significant differences were found in the score of L-SpO2 and morning blood pressures (P>0.05). Wearing dentures might lead to an increase of AHI during sleep among edentulous people.

  6. Automatic, computer-based speech assessment on edentulous patients with and without complete dentures - preliminary results.

    PubMed

    Stelzle, F; Ugrinovic, B; Knipfer, C; Bocklet, T; Nöth, E; Schuster, M; Eitner, S; Seiss, M; Nkenke, E

    2010-03-01

    Dental rehabilitation of edentulous patients with complete dentures includes not only aesthetics and mastication of food, but also speech quality. It was the aim of this study to introduce and validate a computer-based speech recognition system (ASR) for automatic speech assessment in edentulous patients after dental rehabilitation with complete dentures. To examine the impact of dentures on speech production, the speech outcome of edentulous patients with and without complete dentures was compared. Twenty-eight patients reading a standardized text were recorded twice - with and without their complete dentures in situ. A control group of 40 healthy subjects with natural dentition was recorded under the same conditions. Speech quality was evaluated by means of a polyphone-based ASR according to the percentage of the word accuracy (WA). Speech acceptability assessment by expert listeners and the automatic rating of the WA by the ASR showed a high correlation (corr = 0.71). Word accuracy was significantly reduced in edentulous speakers (55.42 +/- 13.1) compared to the control group's WA (69.79 +/- 10.6). On the other hand, wearing complete dentures significantly increased the WA of the edentulous patients (60.00 +/- 15.6). Speech production quality is significantly reduced after complete loss of teeth. Reconstitution of speech production quality is an important part of dental rehabilitation and can be improved for edentulous patients by means of complete dentures. The ASR has proven to be a useful and easily applicable tool for automatic speech assessment in a standardized way.

  7. Implementation and commissioning of an integrated micro-CT/RT system with computerized independent jaw collimation

    SciTech Connect

    Jensen, Michael D.; Hrinivich, W. Thomas; Jung, Jongho A.; Holdsworth, David W.; Drangova, Maria; Chen, Jeff; Wong, Eugene

    2013-08-15

    Purpose: To design, construct, and commission a set of computer-controlled motorized jaws for a micro-CT/RT system to perform conformal image-guided small animal radiotherapy.Methods: The authors designed and evaluated a system of custom-built motorized orthogonal jaws, which allows the delivery of off-axis rectangular fields on a GE eXplore CT 120 preclinical imaging system. The jaws in the x direction are independently driven, while the y-direction jaws are symmetric. All motors have backup encoders, verifying jaw positions. Mechanical performance of the jaws was characterized. Square beam profiles ranging from 2 × 2 to 60 × 60 mm{sup 2} were measured using EBT2 film in the center of a 70 × 70 × 22 mm{sup 3} solid water block. Similarly, absolute depth dose was measured in a solid water and EBT2 film stack 50 × 50 × 50 mm{sup 3}. A calibrated Farmer ion chamber in a 70 × 70 × 20 mm{sup 3} solid water block was used to measure the output of three field sizes: 50 × 50, 40 × 40, and 30 × 30 mm{sup 2}. Elliptical target plans were delivered to films to assess overall system performance. Respiratory-gated treatment was implemented on the system and initially proved using a simple sinusoidal motion phantom. All films were scanned on a flatbed scanner (Epson 1000XL) and converted to dose using a fitted calibration curve. A Monte Carlo beam model of the micro-CT with the jaws has been created using BEAMnrc for comparison with the measurements. An example image-guided partial lung irradiation in a rat is demonstrated.Results: The averaged random error of positioning each jaw is less than 0.1 mm. Relative output factors measured with the ion chamber agree with Monte Carlo simulations within 2%. Beam profiles and absolute depth dose curves measured from the films agree with simulations within measurement uncertainty. Respiratory-gated treatments applied to a phantom moving with a peak-to-peak amplitude of 5 mm showed improved beam penumbra (80%–20%) from 3.9 to

  8. Jaw adductor muscles across lepidosaurs: a reappraisal.

    PubMed

    Daza, Juan Diego; Diogo, Rui; Johnston, Peter; Abdala, Virginia

    2011-10-01

    The exact homologies of tetrapod jaw muscles remain unresolved, and this provides a barrier for phylogenetic analysis and tracing character evolution. Here, lepidosaur jaw muscles are surveyed using direct examination of species from 23 families and published descriptions of species from 10 families. A revised nomenclature is applied according to proposed homologies with Latimeria. Among lepidosaurs, variation was found in many aspects of jaw muscle anatomy. The superficial layers mm. levator and retractor anguli oris (LAO and RAO) are present in Sphenodon but not all squamates. The external jaw adductor muscles universally present in lepidosaurs are homologous with the main adductor muscle, A2, of Latimeria and include four layers: superficialis (A2-SUP), medialis (A2-M), profundus (A2-PRO), and posterior (A2-PVM). The A2-SUP appears divided in Agamidae, Gekkota, Xantusiidae, and Varanidae. The A2-M is layered lateromedial in lizards but anteroposterior in snakes. The names pseudotemporalis (PS) and pterygomandibularis (PTM) are recommended for subdivisions of the internal adductors of reptiles and amphibians, because the homology of this muscle with the A3' and A3 ″ of Latimeria remains inconclusive. The intramandibularis of lepidosaurs and Latimeria (A-ω) are homologous. The distribution of six jaw muscle characters was found to plot more parsimoniously on phylogenies based on morphological rather than and molecular data. Character mapping indicates that Squamata presents reduction in the divisions of the A2-M, Scincoidea presents reduction or loss of LAO, and two apomorphic features are found for the Gekkota.

  9. [Fixed restorations of a dentition with reduced periodontal support in partially edentulous patients].

    PubMed

    De Boever, J A

    1990-05-01

    Placing restorations in patients who have a limited number of teeth and reduced periodontal support is no longer controversial, given careful selection of patients, preprosthetic periodontal treatment, and a thorough maintenance program. In this paper, attention is drawn to general prosthetic planning, including the use of long-span bridges. Because of increased tooth mobility, cross-arch stabilization of the bridges with interlocks or with postsolder connections is advocated. The framework should be rigid enough to avoid deflection of the bridges. Preparation of the vital and nonvital abutment teeth needs much attention. To avoid using a removable prosthesis, a cantilever bridge can be used, but it makes the construction more prone to fracture. A number of periodontal-prosthetic patients demonstrate a "posterior collapsed bite." Rehabilitation requires the restoration at a "new" vertical dimension of occlusion. This can be done, without functional hazards, in a one-step clinical procedure. A long functional adaptation period is unnecessary. The treatment outcome of furcations is not always predictable. Therefore, hemisection or amputation are often the treatments of choice. On these hemisected roots, bridges can be made and successfully maintained. Finally, it should be stressed that not all teeth have to be replaced: a premolar, shortened-arch occlusion is often sufficient for adequate function.

  10. Successful rehabilitation of partial edentulous maxilla and mandible with new type of implants: molecular precision implants.

    PubMed

    Danza, Matteo; Lauritano, Dorina; Carinci, Francesco

    2014-01-01

    The extraction of teeth results in rapid bone resorption both vertically and horizontally in the first month. The loss of alveolar ridge reduces the chance of implant rehabilitation. Atraumatic extraction, implant placement in extraction socket, and an immediate prosthesis have been proposed as alternative therapies to maintain the volume and contours tissue and reduce time and cost of treatment. The immediate load of implants is a universally practiced procedure; nevertheless a successful procedure requires expertise in both the clinical and the reconstructive stages using a solid implant system. Excellent primary stability and high bone-implant contact are only minimal requirements for any type of implant procedure. In this paper we present a case report using a new type of implants. The new type of implants, due to its sophisticated control system of production, provides to the implantologist a safe and reliable implant, with a macromorphology designed to ensure a close contact with the surrounding bone.

  11. Successful Rehabilitation of Partial Edentulous Maxilla and Mandible with New Type of Implants: Molecular Precision Implants

    PubMed Central

    Danza, Matteo; Carinci, Francesco

    2014-01-01

    The extraction of teeth results in rapid bone resorption both vertically and horizontally in the first month. The loss of alveolar ridge reduces the chance of implant rehabilitation. Atraumatic extraction, implant placement in extraction socket, and an immediate prosthesis have been proposed as alternative therapies to maintain the volume and contours tissue and reduce time and cost of treatment. The immediate load of implants is a universally practiced procedure; nevertheless a successful procedure requires expertise in both the clinical and the reconstructive stages using a solid implant system. Excellent primary stability and high bone-implant contact are only minimal requirements for any type of implant procedure. In this paper we present a case report using a new type of implants. The new type of implants, due to its sophisticated control system of production, provides to the implantologist a safe and reliable implant, with a macromorphology designed to ensure a close contact with the surrounding bone. PMID:25525437

  12. Drug induced osteonecrosis of the jaw.

    PubMed

    Hamadeh, Issam S; Ngwa, Bridget A; Gong, Yan

    2015-05-01

    Despite the widespread use of bisphosphonates and their unequivocal efficacy for the treatment of various disease states, osteonecrosis of the jaw remains one of the most feared complications associated with their use. Current evidence, however, suggests that there is also a relationship between occurrence of osteonecrosis of the jaw and use of other classes of pharmacotherapies namely RANKL inhibitors as well as angiogenesis inhibitors. Although these drugs have different mechanisms of action than bisphosphonates, they all seem to interfere with the bone remodeling process i.e. alter the balance between bone resorption and bone formation which may be the most plausible explanation for pathogenesis of osteonecrosis of the jaw. The main objective of this review is to introduce the readership to a number of relatively new medications that may cause osteonecrosis of the jaw. Accordingly, we will summarize latest findings from clinical studies, meta analyses and case reports published in medical literature on this topic. For some of these medications, the evidence may not appear as robust as that for bisphosphonates; yet, the possibility of this adverse event occurring with these non bisphosphonate drugs should never be precluded unless proven otherwise. Thus, it is imperative that health care providers implement preventive measures so as to circumvent the incidence of osteonecrosis of the jaw. In this day of age where medical care is becoming personalized, we will highlight some of significant findings from studies seeking to identify genetic markers that may potentially play a role in development of osteonecrosis of the jaw. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Soft Bodies, Hard Jaws: An Introduction to the Symposium, with Rotifers as Models of Jaw Diversity.

    PubMed

    Hochberg, Rick; Wallace, Robert L; Walsh, Elizabeth J

    2015-08-01

    Jaws have evolved numerous times in the animal kingdom and they display a wide variety of structural, compositional, and functional characteristics that reflect their polyphyletic origins. Among soft-bodied invertebrates, jaws are known from annelids, chaetognaths, flatworms, gnathostomulids, micrognathozoans, mollusks, rotifers, and several ecdysozoans. Depending on the taxon, jaws may function in the capture of prey (e.g., chaetognaths and flatworms), processing of prey (e.g., gnathostomulids and onychophorans), or both (e.g., rotifers). Although structural diversity among invertebrates’ jaws is becoming better characterized with the use of electron microscopy, many details remain poorly described, including neuromuscular control, elemental composition, and physical characteristics, such as hardness and resistance to wear. Unfortunately, absence of relevant data has impeded understanding of their functional diversity and evolutionary origins. With this symposium, we bring together researchers of disparately jawed taxa to draw structural and mechanistic comparisons among species to determine their commonalities. Additionally, we show that rotifers’ jaws, which are perhaps the best-characterized jaws among invertebrates, are still enigmatic with regard to their origins and mechanics. Nevertheless, technologies such as energy dispersive X-ray spectroscopy (EDX) and 3D modeling are being used to characterize their chemical composition and to develop physical models that allow exploration of their mechanical properties, respectively. We predict that these methods can also be used to develop biomimetic and bioinspired constructs based on the full range of the complexity of jaws, and that such constructs also can be developed from other invertebrate taxa. These approaches may also shed light on common developmental and physiological processes that facilitate the evolution of invertebrates’ jaws.

  14. Breastfeeding is early functional jaw orthopedics (an introduction).

    PubMed

    Page, D C

    2001-01-01

    Breastfeeding places beneficial orthopedic forces on the jaws, similar to the forces of Functional Jaw Orthopedics--the newest form of orthodontics. To date most breastfeeding benefits have been attributed to the content of mother's milk. The true orthopedic benefits of breastfeeding, suckling, deserve more definitive attention and research. Breastfeeding is early preventive Functional Jaw Orthopedics because breastfeeding forces impact the jaws during a very rapid period of infant jaw growth. Breast suckling aids proper development of the jaws which form the gateway to the human airway. Bottle, pacifier and digit sucking deform jaws and airways. Forward forces of suckling clearly oppose the backward forces of sucking. Dentists who understand the positive impact of forward orthopedic forces on the jaws should support and advocate exclusive breastfeeding for about 6 months.

  15. Edentulous patients' knowledge of dental hygiene and care of prostheses.

    PubMed

    de Castellucci Barbosa, Luciano; Ferreira, Manoela Rejane Maia; de Carvalho Calabrich, Carolina Freire; Viana, Aline Cavalcanti; de Lemos, Maria Catarina Lavigne; Lauria, Roberta Andrade

    2008-06-01

    The aim of this study was to analyse denture users' oral care habits with regard to the use of their prostheses. Rehabilitative treatment is only successful when patients are motivated and aware of correct prosthesis use and hygiene. Questionnaires were distributed to 150 complete denture users at the Federal University of Bahia School of Dentistry, the Esmeralda Natividade Health Center, the Bahian Science Development Foundation and a Salvador nursing home. The questionnaire included information on gender, age, length of prosthesis use, cleaning methods and materials, etc. The data were analysed using EpiInfo version 6 software. The chi-squared test was used for statistical analysis, with a significance level of 5%. Questionnaire results showed that 78% of the subjects, with an average age of 67.3 years, had used the same complete denture for over 5 years. 64% slept with their prostheses and 44% removed them from the mouth only for cleaning. None of the patients interviewed knew anything about brushes designed specifically for complete dentures. 37.3% had a restricted diet and 44% believed that a complete denture would last for more than 10 years. Within the limitations of this study, it was concluded that the edentulous patients surveyed had limited awareness of prosthetic hygiene and long-term oral care despite extended periods of denture use.

  16. Exploratory factor analysis of the Brazilian OHIP for edentulous subjects.

    PubMed

    Souza, R F; Leles, C R; Guyatt, G H; Pontes, C B; Della Vecchia, M P; Neves, F D

    2010-03-01

    The use of seven domains for the Oral Health Impact Profile (OHIP)-EDENT was not supported for its Brazilian version, making data interpretation in clinical settings difficult. Thus, the aim of this study was to assess patients' responses for the translated OHIP-EDENT in a group of edentulous subjects and to develop factor scales for application in future studies. Data from 103 conventional and implant-retained complete denture wearers (36 men, mean age of 69.1 +/- 10.3 years) were assessed using the Brazilian version of the OHIP-EDENT. Oral health-related quality of life domains were identified by factor analysis using principal component analysis as the extraction method, followed by varimax rotation. Factor analysis identified four factors that accounted for 63% of the 19 items total variance, named masticatory discomfort and disability (four items), psychological discomfort and disability (five items), social disability (five items) and oral pain and discomfort (five items). Four factors/domains of the Brazilian OHIP-EDENT version represent patient-important aspects of oral health-related quality of life.

  17. Prosthesis misfit and marginal bone loss in edentulous implant patients.

    PubMed

    Jemt, T; Book, K

    1996-01-01

    The objective of this study was to statistically correlate in vivo measurements of prosthesis misfit and change of marginal bone level in implants placed in the edentulous maxilla. Two groups, each comprising seven patients, were followed up either prospectively for 1 year or retrospectively for the last 4 years of the 5-year period after second-stage surgery. Measurements of prosthesis misfit were performed by means of a three-dimensional photogrammetric technique, and marginal bone levels were measured from standard intraoral radiographs. Results showed that none of the prostheses presented a completely passive fit to the implants in vivo. Furthermore, similar distortions of the prostheses were found in the two groups, indicating that the implants seemed to be stable and did not move, even after several years in function. The maximal range of three-dimensional distortion of cylinder center points was about 275 microns for both groups. Mean center point misfit was 111 (SD 59) and 91 (SD 51) microns for the 1-year and 5-year groups, respectively. The corresponding mean marginal bone loss was 0.5 and 0.2 mm for the two follow-up groups. No statistical correlations (P > .05) between change of marginal bone levels and different parameters of prosthesis misfit were observed in the two groups. The study indicated that a certain biologic tolerance for misfit may be present. The degree of misfit reported in the study was clinically acceptable with regard to observed marginal bone loss.

  18. Edentulous child with Allgrove syndrome: a rare case report

    PubMed Central

    Vahedi, Mohammad; Allahbakhshi, Hanif

    2016-01-01

    Triple-A syndrome, also known as Allgrove syndrome, is a rare autosomal recessive disorder. The 3 features of this syndrome are achalasia, adrenal insufficiency, and alacrima. Achalasia could be the first manifestation of the triple-A syndrome; however, its etiology is unclear. Alacrima is generally asymptomatic but can be detected by obtaining patient history. Although adrenal insufficiency could have manifestations such as asthenia, it might be wrongly diagnosed as muscle fatigue. Vitamin D and calcium supplements are usually prescribed for the prevention of osteoporosis. Neurologic manifestations could be present in adults. In some individuals with this disorder, genetic examination indicates mutations in both alleles of the AAAS gene, which encodes a special 546-amino-acid protein designated ALADIN, and in chromosome 12q13. The genetic cause of the triple A syndrome in some patients who do not have an identified mutation is unknown. While very few such cases have been reported till date, one such case was presented to us as an edentulous child. PMID:27895694

  19. Obstructive airway disease and edentulism in the atherosclerosis risk in communities (ARIC) study

    PubMed Central

    Offenbacher, Steven; Beck, James D; Barros, Silvana P; Suruki, Robert Y; Loewy, Zvi G

    2012-01-01

    Objectives We examined the potential association between prior chronic obstructive pulmonary disease (COPD) and edentulism, and whether the association varied by COPD severity using data from the Dental Atherosclerosis Risk in Communities Study. Design Cross-sectional. Setting Community dwelling subjects from four US communities. Participants and measurements Cases were identified as edentulous (without teeth) and subjects with one or more natural teeth were identified as dentate. COPD cases were defined by spirometry measurements that showed the ratio of forced expiratory volume (1 s) to vital capacity to be less than 0.7. The severity of COPD cases was also determined using a modified Global Initiative for Chronic Obstructive Lung Disease classification criteria (GOLD stage I–IV). Multiple logistic regression was used to examine the association between COPD and edentulism, while adjusting for age, gender, centre/race, ethnicity, education level, income, diabetes, hypertension, coronary heart disease and congestive heart failure, body mass index, smoking, smokeless tobacco use and alcohol consumption. Results 13 465 participants were included in this analysis (2087 edentulous; 11 378 dentate). Approximately 28.3% of edentulous participants had prior COPD compared with 19.6% among dentate participants (p<0.0001). After adjustment for potential confounders, we observed a 1.3 (1.08 to 1.62) and 2.5 (1.68 to 3.63) fold increased risk of edentulism among GOLD II and GOLD III/IV COPD, respectively, as compared with the non-COPD/dentate referent. Given the short period of time between the measurements of COPD (visit 2) and dentate status (visit 4) relative to the natural history of both diseases, neither temporality nor insight as to the directionality of the association can be ascertained. Conclusions We found a statistically significant association between prior COPD and edentulism, with evidence of a positive incremental effect seen with increasing GOLD

  20. Population prevalence of edentulism and its association with depression and self-rated health

    PubMed Central

    Tyrovolas, Stefanos; Koyanagi, Ai; Panagiotakos, Demosthenes B.; Haro, Josep Maria; Kassebaum, Nicholas J.; Chrepa, Vanessa; Kotsakis, Georgios A.

    2016-01-01

    Edentulism is associated with various adverse health outcomes but treatment options in low- and middle-income countries (LMICs) are limited. Data on its prevalence and its effect on mental health and overall-health is lacking, especially from LMICs. Self-reported data on complete edentulism obtained by standardized questionnaires on 201,953 adults aged ≥18 years from 50 countries which participated in the World Health Survey (WHS) 2002–2004 were analyzed. Age and sex-standarized edentulism prevalence ranged from 0.1% (95% CI = 0.0–0.3) (Myanmar) to 14.5% (95% CI = 13.1–15.9) (Zimbabwe), and 2.1% (95% CI = 1.5–3.0) (Ghana) to 32.3% (95% CI = 29.0–35.8) (Brazil) in the younger and older age groups respectively. Edentulism was significantly associated with depression (OR 1.57, 95% CI = 1.23–2.00) and poor self-rated health (OR 1.38, 95% CI = 1.03–1.83) in the younger group with no significant associations in the older age group. Our findings highlight the edentulism-related health loss in younger persons from LMICs. The relative burden of edentulism is likely to grow as populations age and live longer. Given its life-long nature and common risk factors with other NCDs, edentulism surveillance and prevention should be an integral part of the global agenda of NCD control. PMID:27853193

  1. Population prevalence of edentulism and its association with depression and self-rated health.

    PubMed

    Tyrovolas, Stefanos; Koyanagi, Ai; Panagiotakos, Demosthenes B; Haro, Josep Maria; Kassebaum, Nicholas J; Chrepa, Vanessa; Kotsakis, Georgios A

    2016-11-17

    Edentulism is associated with various adverse health outcomes but treatment options in low- and middle-income countries (LMICs) are limited. Data on its prevalence and its effect on mental health and overall-health is lacking, especially from LMICs. Self-reported data on complete edentulism obtained by standardized questionnaires on 201,953 adults aged ≥18 years from 50 countries which participated in the World Health Survey (WHS) 2002-2004 were analyzed. Age and sex-standarized edentulism prevalence ranged from 0.1% (95% CI = 0.0-0.3) (Myanmar) to 14.5% (95% CI = 13.1-15.9) (Zimbabwe), and 2.1% (95% CI = 1.5-3.0) (Ghana) to 32.3% (95% CI = 29.0-35.8) (Brazil) in the younger and older age groups respectively. Edentulism was significantly associated with depression (OR 1.57, 95% CI = 1.23-2.00) and poor self-rated health (OR 1.38, 95% CI = 1.03-1.83) in the younger group with no significant associations in the older age group. Our findings highlight the edentulism-related health loss in younger persons from LMICs. The relative burden of edentulism is likely to grow as populations age and live longer. Given its life-long nature and common risk factors with other NCDs, edentulism surveillance and prevention should be an integral part of the global agenda of NCD control.

  2. Self-aligning fixture used in lathe chuck jaw refacing

    NASA Technical Reports Server (NTRS)

    Linn, C. C.

    1965-01-01

    Self-aligning tool positions and rigidly holds lathe chuck jaws for refacing and truing of the clamping surface. The jaws clamp the fixture in the manner of clamping a workpiece. The fixture can be modified to accommodate four-jawed checks.

  3. Biomechanical analysis of jaw-closing movements.

    PubMed

    Koolstra, J H; van Eijden, T M

    1995-09-01

    This study concerns the complex interaction between active muscle forces and passive guiding structures during jaw-closing movements. It is generally accepted that the ligaments of the joint play a major role in condylar guidance during these movements. While these ligaments permit a wide range of motions, it was assumed that they are not primarily involved in force transmission in the joints. Therefore, it was hypothesized that muscle forces and movement constraints caused by the articular surfaces imply a necessary and sufficient condition to generate ordinary jaw-closing movements. This hypothesis was tested by biomechanical analysis. A dynamic six-degrees-of-freedom mathematical model of the human masticatory system has been developed for qualitative analysis of the contributions of the different masticatory muscles to jaw-closing movements, it was found that the normally observed movement, which includes a swing-slide condylar movement along the articular eminence, can be generated by various separate pairs of masticatory muscles, among which the different parts of the masseter as well as the medial pterygoid muscle appeared to be the most suitable to complete this action. The results seem to be in contrast to the general opinion that a muscle with a forward-directed force component may not be suitable for generating jaw movements in which the condyle moves backward. The results can be explained, however, by biomechanical analysis which includes not only muscle and joint forces as used in standard textbooks of anatomy, but also the torques generated by these forces.

  4. Effects of eccentric jaw exercise on temporal summation in jaw-closing muscles of healthy subjects.

    PubMed

    Torisu, Tetsurou; Wang, Kelun; Svensson, Peter; De Laat, Antoon; Tanaka, Mihoko; Shimada, Akiko; Ikoma, Akiko; Murata, Hiroshi; Arendt-Nielsen, Lars

    2010-08-01

    Eccentric jaw exercises has been known to cause muscle soreness but no studies have so far examined to what extent temporal summation mechanisms within the exercised muscles are changed. The purpose of the present study was to investigate the effects of an eccentric biting exercise on the temporal summation, mechanical pressure sensitivity and jaw muscle activity. A total of 15 healthy men participated in a two-session-experiment: In one session, they performed 30 min controlled eccentric jaw exercise and the other session served as a no-exercise control. Soreness sensations at rest and during maximal biting, pressure pain thresholds (PPTs) and electromyographic (EMG) activity during maximal jaw biting were recorded before (baseline), immediately after (Post-task), and 1 day after the exercise (1-day-after). The temporal summation ratio using intra-muscular electrical stimulation of the masseter was investigated at baseline and at 1-day-after. The eccentric jaw exercise was associated with significant increases in soreness sensation and decreased PPTs at Post-task and at 1-day-after. The EMG activity and biting force did not change. The summation ratio was significantly decreased at 1-day-after in both sessions. The present findings demonstrate that eccentric jaw exercise does not induce detectable changes in temporal summation. However, the summation ratio may have clinical utility to differentiate the location of sensitization. Copyright (c) 2009 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

  5. Mapping, profiling and clustering of pressure pain threshold (PPT) in edentulous oral mucosa.

    PubMed

    Ogawa, T; Tanaka, M; Ogimoto, T; Okushi, N; Koyano, K; Takeuchi, K

    2004-03-01

    Edentulous oral mucosa involves different tissue types, various innervation and wound healing process. We hypothesized that pressure pain threshold (PPT) of edentulous oral mucosa varies significantly among different regions. The objective of this study is to examine regional differences and correlations of PPT in edentulous oral mucosa. Pain threshold (PPT) was measured at 112 sites in 15 edentulous patients using an electric-controlled pressure algometer. PPT mapping was created by the level of PPT, and PPT clustering was undertaken based on the inter-site correlation of PPT. PPT increased from the anterior to posterior alveolus in both maxilla and mandible, but decreased from the anterior palate to the posterior palate. PPT decreased from the ridge crest to the buccal vestibule. The inter-site difference was four fold within the maxilla and 2.4 fold within the mandible. Principal component analysis applied on PPT inter-site correlation matrix revealed that the maxilla and mandible could be differentiated statistically. The maxilla and mandible were divided into three and four clusters, respectively. These results demonstrate that different areas of edentulous oral mucosa have different PPT and that the PPT varies proportionally in selected areas, providing useful diagnostic and therapeutic information in removable prosthodontics and a new opportunity for understanding pain underneath the denture.

  6. Edentulism risk indicators among Mexican elders 60-year-old and older.

    PubMed

    Islas-Granillo, H; Borges-Yañez, S A; Lucas-Rincón, S E; Medina-Solís, C E; Casanova-Rosado, A J; Márquez-Corona, M L; Maupomé, G

    2011-01-01

    The objective of this study was to determine the prevalence of edentulism in Mexican elders aged 60 years and older, and the associated risk indicators. A cross-sectional study was undertaken in 139 elders living in either of two long-term care (LTC) facilities, or attending an adult day center (ADC) in Pachuca, Mexico. A subject was edentulous when natural teeth were completely absent, determined through a clinical examination. Risk indicators were collected using questionnaires. Analyses were performed using binary logistic regression in STATA 9.0. Mean age was 79.0±9.8 years. Many subjects were women (69.1%). The prevalence of edentulism was 36.7%. In multivariate analysis, after adjusting for age and sex, the variables that were inversely associated (p<0.05) with edentulism were living with a spouse (odds ratio=OR=0.31), and lacking health insurance (OR=0.70). Variables associated with higher risk of being edentate were lower educational attainment (OR=1.61), having received radiation therapy (OR=4.49), being a smoker (OR=4.82), and having diabetes (OR=2.94) or other chronic illnesses (OR=1.82) (with hypertension approaching significance, p=0.067). In this sample of Mexican elders, diverse variables were associated with edentulism, in particular smoking and past radiotherapy. Oral health programs within and outside LTC/ADC should take into account risk factors specific to the older population.

  7. [Clinical epidemiological study of xerostomia in elderly totally edentulous].

    PubMed

    Pescio, Jorge J

    2006-01-01

    Because of an increasing number of older people in our community presenting with a variable decrease of salivary flow which affects their quality of life, we aimed to analyze the prevalence of salivary decrease and xerostomia in relation to various causing factors. The objective of this study was to analyze the prevalence of a decrease of normal salivary secretion and xerostomia in relation to various factors in the older population of our community. One hundred and twenty-six edentulous male and female subjects older than 50 years (62.41 8.24) were entered . A chart was specially designed for this study where both local and general predisposing factors were recorded. The results were statistically analyzed.(P < 0.05) 40.5% of the subjects had xerostomia. The number of cases increased with age and was larger among women, being differences statistically significant in women aged 60-69 years. 34.9% appeared to be in good health, 65.1% suffered from one or more systemic diseases, while 53.3% used medication daily (2.4 +/- 1.10 daily drugs). There were significant differences when scarce salivary flow and a feeling of oral dryness were associated with health problems and the use of medication. The study showed that old age is a major factor in the decrease of salivary secretion and xerostomia, and that women are usually more affected. Xerostomia may be attributed to various causes. It is not considered a disease but a clinical manifestation of oral dryness with or without hyposalivation. Once the disorder has been identified, health professionals should join to design a suitable treatment planning.

  8. Surface EMG of jaw-elevator muscles and chewing pattern in complete denture wearers.

    PubMed

    Piancino, M G; Farina, D; Talpone, F; Castroflorio, T; Gassino, G; Margarino, V; Bracco, P

    2005-12-01

    The aim of this study was to investigate the adaptation process of masticatory patterns to a new complete denture in edentulous subjects. For this purpose, muscle activity and kinematic parameters of the chewing pattern were simultaneously assessed in seven patients with complete maxillary and mandibular denture. The patients were analysed (i) with the old denture, (ii) with the new denture at the delivery, (iii) after 1 month and (iv) after 3 months from the delivery of the new denture. Surface electromyographic (EMG) signals were recorded from the masseter and temporalis anterior muscles of both sides and jaw movements were tracked measuring the motion of a tiny magnet attached at the lower inter-incisor point. The subjects were asked to chew a bolus on the right and left side. At the delivery of the new denture, peak EMG amplitude of the masseter of the side of the bolus was lower than with the old denture and the masseters of the two sides showed the same intensity of EMG activity, contrary to the case with the old denture. EMG amplitude and asymmetry of the two masseter activities returned as with the old denture in 3 months. The EMG activity in the temporalis anterior was larger with the old denture than in the other conditions. The chewing cycle width and lateral excursion decreased at the delivery of the new denture and recovered after 3 months.

  9. Architecture of the human jaw-closing and jaw-opening muscles.

    PubMed

    Van Eijden, T M; Korfage, J A; Brugman, P

    1997-07-01

    The human jaw-closing and jaw-opening muscles produce forces leading to the development of three-dimensional bite and chewing forces and to three-dimensional movements of the jaw. The length of the sarcomeres is a major determinant for both force and velocity, and the maximal work, force, and shortening range each muscle is capable of producing are proportional to the architectural parameter volume, physiological cross-sectional area, and fiber length, respectively. In addition, the mechanical role the muscles play is strongly related to their three-dimensional position and orientation in the muscle-bone-joint system. The objective of this study was to compare relevant architectural characteristics for the jaw-closing and jaw-opening muscles and to provide a set of data that can be used in biomechanical modeling of the masticatory system. In eight cadavers, sarcomere lengths, muscle masses, fiber lengths, pennation angles, and physiological cross-sectional areas were determined for the following muscles: superficial and deep masseter, anterior and posterior temporalis, anterior and posterior medial pterygoid, inferior and superior lateral pterygoid, posterior and anterior digastric, geniohyoid, posterior and anterior mylohyoid, and stylohyoid. To determine the spatial position of their action lines, the three-dimensional coordinates of the attachment sites were registered. Compared with the jaw openers, the jaw closers were characterized by shorter sarcomere lengths at the closed jaw, larger masses of contractile and tendinous tissue, larger physiological cross-sectional areas, larger pennation angles, shorter fiber lengths, shorter moment arms, and lower fiber-length-to-muscle-length ratios. In addition, architectural features differed across the muscles of the same functional group. Sarcomere length did not differ significantly among the regions of the same muscle. In contrast, in some muscles, significant intramuscular differences were found with respect to, e

  10. Coordination of jaw and extrinsic tongue muscle activity during rhythmic jaw movements in anesthetized rabbits.

    PubMed

    Ariyasinghe, Sajjiv; Inoue, Makoto; Yamamura, Kensuke; Harasawa, Yohji; Kurose, Masayuki; Yamada, Yoshiaki

    2004-08-06

    To clarify the jaw-closer and tongue-retractor muscle activity patterns during mastication, electromyographic activity of the styloglossus (SG) as a tongue-retractor and masseter (Mass) as a jaw-closer muscles as well as jaw-movement trajectories were recorded during cortically evoked rhythmic jaw movements (CRJMs) in anesthetized rabbits. The SG and Mass muscles were mainly active during the jaw-closing (Cl) phase. The SG activity was composed of two bursts in one masticatory cycle; one had its peak during the jaw-opening (Op) phase (SG1 burst) and the other during the Cl phase (SG2 burst). The Mass activity during the Cl phase was dominant on the working side (opposite to the stimulating side) while the SG1 and SG2 bursts were not different between the sides. When the wooden stick was inserted between the molar teeth on the working side during CRJMs, the facilitatory effects on the SG1 and SG2 bursts on both sides were noted as well as those on the Mass bursts, but the effects on the SG1 burst seemed to be weak as compared with those on the Mass and SG2 bursts. The difference in the burst timing between the sides was noted only in the SG1 burst. When the trigeminal nerves were blocked, the peak and area of the SG and Mass burst decreased during CRJMs, and the facilitatory effects of the wooden stick application on the muscles were not noted. The results suggest that the jaw and tongue muscle activities may be adjusted to chew the food and make the food bolus.

  11. Vinyl polysiloxane impression material in removable prosthodontics. Part 1: edentulous impressions.

    PubMed

    Massad, Joseph J; Cagna, David R

    2007-08-01

    Recent advances in impression materials and stock edentulous impression trays have resulted in simplified approaches to impression making in removable prosthodontics. Once considered an absolute necessity, it is now possible to avoid the need for custom impression trays. In an effort to achieve reliable master casts in a single appointment, new and innovative procedures are now available. This article, the first in a 3-part series, will review historical information, basic concepts, materials considerations, and philosophic approaches to impression making in complete-denture therapy. A modem technique using readily available impression materials will be described and illustrated so readers can consider the benefits of incorporation into their daily management of edentulous patients.

  12. Vinyl polysiloxane impression material in removable prosthodontics. Part 1: Edentulous impressions.

    PubMed

    Massad, Joseph J; Cagna, David R

    2009-02-01

    Recent advances in impression materials and stock edentulous impression trays have resulted in simplified approaches to impression making in removable prosthodontics. Once considered an absolute necessity, it is now possible to avoid the need for custom impression trays. In an effort to achieve reliable master casts in a single appointment, new and innovative procedures are now available. This article, the first in a 3-part series, will review historical information, basic concepts, materials considerations, and philosophic approaches to impression making in complete-denture therapy. A modern technique using readily available impression materials will be described and illustrated so readers can consider the benefits of incorporation into their daily management of edentulous patients.

  13. Rationale for and Evaluation of a CAI Tutorial in a Removable Partial Prosthodontics Classification System

    ERIC Educational Resources Information Center

    Tira, Daniel E.

    1977-01-01

    A CAI tutorial for learning the Applegate-Kennedy (dental) Classification System for Partially Edentulous (toothless) Situations was developed at University of Missouri-Kansas City School of Dentistry. Evaluative data from three comparison groups of second year students indicated that this is generally a viable instructional alternative to…

  14. Clinical investigation on axial versus tilted implants for immediate fixed rehabilitation of edentulous arches: preliminary results of a single cohort study.

    PubMed

    Agnini, Alessandro; Agnini, Andrea Mastrorosa; Romeo, Davide; Chiesi, Manuele; Pariente, Leon; Stappert, Christian F J

    2014-08-01

    The purpose of this clinical investigation was to evaluate full-arch fixed-dental restorations supported by immediate loaded axial and tilted implants in a single-cohort study. Survival rate of axial and tilted implants was compared. From 2006 to 2010, 30 patients were recruited and treated with dental implants. Provisional fixed-dental prostheses were screw-retained over axial or axial and tilted implants within 24 hours after surgery. Follow-ups at 6, 12, and 24 months and annually up to 5 years were scheduled, and radiographic evaluation of peri-implant bone level changes was conducted. Thirty patients (20 females and 10 males) were followed up for an average of 44 months (range 18-67 months). Six patients received both upper and lower implant rehabilitations, resulting in 36 restorations. A total of two hundred two implants were placed (maxilla = 118; mandible = 84) and 46% of the fixtures were evaluated at the 4-year recall. Four axial implants were lost in three patients, leading to 98.02% implant (97.56% axial implants and 100% tilted implants) and 100% prosthetic cumulative survival rate, respectively. No significant difference in marginal bone loss was found between tilted and axial implants in both jaws at 1-year evaluation. Midterm results confirmed that immediate loading of axial and tilted implants provides a viable treatment modality for the rehabilitation of edentulous arches. © 2012 Wiley Periodicals, Inc.

  15. Chemical and Radiation Associated Jaw Lesions

    PubMed Central

    Omolehinwa, Temitope T.; Akintoye, Sunday O.

    2015-01-01

    Synopsis Osteonecrosis of the jaw, at one time considered to be infrequent has now become a major public health concern not only in the United States, but throughout the world. The wide-spread use of radiotherapy for head and neck cancer as well as bone antiresorptives and antiangiogenic agents have increased the incidence of osteonecrosis. While the exact pathophysiological process of osteonecrosis is yet to be clearly defined, there has been a much higher incidence of medication-related osteonecrosis of the jaw relative to the other types of osteonecrosis. The traditional osteoradionecrosis still occurs despite better treatment planning and shielding to minimize collateral damage to bone. There are other related necrotic lesions secondary to usage of recreation drugs and the use of steroids. This chapter will give comprehensive information about these different types of bone necrosis; provide the readers with radiographic diagnostic criteria and updates on current theories on pathophysiology of osteonecrosis. PMID:26614957

  16. Heterogeneous conservation of Dlx paralog co-expression in jawed vertebrates.

    PubMed

    Debiais-Thibaud, Mélanie; Metcalfe, Cushla J; Pollack, Jacob; Germon, Isabelle; Ekker, Marc; Depew, Michael; Laurenti, Patrick; Borday-Birraux, Véronique; Casane, Didier

    2013-01-01

    The Dlx gene family encodes transcription factors involved in the development of a wide variety of morphological innovations that first evolved at the origins of vertebrates or of the jawed vertebrates. This gene family expanded with the two rounds of genome duplications that occurred before jawed vertebrates diversified. It includes at least three bigene pairs sharing conserved regulatory sequences in tetrapods and teleost fish, but has been only partially characterized in chondrichthyans, the third major group of jawed vertebrates. Here we take advantage of developmental and molecular tools applied to the shark Scyliorhinus canicula to fill in the gap and provide an overview of the evolution of the Dlx family in the jawed vertebrates. These results are analyzed in the theoretical framework of the DDC (Duplication-Degeneration-Complementation) model. The genomic organisation of the catshark Dlx genes is similar to that previously described for tetrapods. Conserved non-coding elements identified in bony fish were also identified in catshark Dlx clusters and showed regulatory activity in transgenic zebrafish. Gene expression patterns in the catshark showed that there are some expression sites with high conservation of the expressed paralog(s) and other expression sites with events of paralog sub-functionalization during jawed vertebrate diversification, resulting in a wide variety of evolutionary scenarios within this gene family. Dlx gene expression patterns in the catshark show that there has been little neo-functionalization in Dlx genes over gnathostome evolution. In most cases, one tandem duplication and two rounds of vertebrate genome duplication have led to at least six Dlx coding sequences with redundant expression patterns followed by some instances of paralog sub-functionalization. Regulatory constraints such as shared enhancers, and functional constraints including gene pleiotropy, may have contributed to the evolutionary inertia leading to high

  17. Heterogeneous Conservation of Dlx Paralog Co-Expression in Jawed Vertebrates

    PubMed Central

    Debiais-Thibaud, Mélanie; Metcalfe, Cushla J.; Pollack, Jacob; Germon, Isabelle; Ekker, Marc; Depew, Michael; Laurenti, Patrick

    2013-01-01

    Background The Dlx gene family encodes transcription factors involved in the development of a wide variety of morphological innovations that first evolved at the origins of vertebrates or of the jawed vertebrates. This gene family expanded with the two rounds of genome duplications that occurred before jawed vertebrates diversified. It includes at least three bigene pairs sharing conserved regulatory sequences in tetrapods and teleost fish, but has been only partially characterized in chondrichthyans, the third major group of jawed vertebrates. Here we take advantage of developmental and molecular tools applied to the shark Scyliorhinus canicula to fill in the gap and provide an overview of the evolution of the Dlx family in the jawed vertebrates. These results are analyzed in the theoretical framework of the DDC (Duplication-Degeneration-Complementation) model. Results The genomic organisation of the catshark Dlx genes is similar to that previously described for tetrapods. Conserved non-coding elements identified in bony fish were also identified in catshark Dlx clusters and showed regulatory activity in transgenic zebrafish. Gene expression patterns in the catshark showed that there are some expression sites with high conservation of the expressed paralog(s) and other expression sites with events of paralog sub-functionalization during jawed vertebrate diversification, resulting in a wide variety of evolutionary scenarios within this gene family. Conclusion Dlx gene expression patterns in the catshark show that there has been little neo-functionalization in Dlx genes over gnathostome evolution. In most cases, one tandem duplication and two rounds of vertebrate genome duplication have led to at least six Dlx coding sequences with redundant expression patterns followed by some instances of paralog sub-functionalization. Regulatory constraints such as shared enhancers, and functional constraints including gene pleiotropy, may have contributed to the evolutionary

  18. Jaw opening in novice and experienced classically trained singers.

    PubMed

    Austin, Stephen F

    2007-01-01

    This study examined the amount of jaw opening used by two groups of singers, those with less than 4 years of training (novice) and those with more than 8 years of training (experienced) in the Western tradition of opera and art song. Movement of the jaw in the superior-inferior plane was measured with the use of a lightweight head-mounted cephalostat with a strain gauge. The subjects spoke and then sung a carrier phrase "I say b(v)p," where (v) was each of three vowels, [a], [i], and [u]. The phrase was first spoken with a natural inflection and then sung on a repeated pitch at three notes from the low, medium, and high singing voice range. There was no statistically significant difference in jaw opening between the two groups of singers. Vowel was significant for jaw opening in both groups, with [a] being produced with more jaw opening than [i] or [u]. The voicing condition was also significant for jaw opening with greater jaw opening being used as pitch increased. In general the amount of jaw opening was smallest for the low singing voice condition and greatest for the high singing voice condition. The jaw opening most typically was less in the low voice condition than in the speech condition and then increased for both the medium and high voice tasks. All but two singers used more jaw opening on the [a] vowel than the other two vowels at all voicing conditions.

  19. [Bisphosphonate-associated osteonecrosis of the jaw].

    PubMed

    Koy, S; Schubert, M; Koy, J; Ney, M; Lauer, G; Sabatowski, R

    2015-04-01

    Bisphosphonates (BP) are used in the treatment of severe osteoporosis and metastasis of malignant diseases. A possible relationship between the occurrence of osteonecrosis of the jaw and BP therapy was first described in 2003. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is difficult to treat. In some cases the condition of the patients is so compromised that only minimally invasive surgery is possible. Histopathologically, osteonecrosis shows the features of chronic sequestered osteomyelitis, which can be found in different areas of the upper and lower jaw. Sometimes extensive resections of the jaw are necessary. Thus, BRONJ can cause mutilation, impairment of function and esthetics in the orofacial system and, thereby, compromise the life quality of the patients. Triggering factors are often tooth extraction without surgical plastic wound closure of the alveoli, but can also be associated with bruises from denture or other minor wounds. The purpose of this article is to present results from our own patient collective, including therapy regime, success rate, and therapy recommendations. The patient populations at three German hospitals were analyzed using a standard questionnaire. The patients in the study group, entered into a follow-up system for early detection of possible BRONJ, were evaluated for treatement outcome. The success rate for prophylactic surgery in asymptomatic patients was very high at 96 %. In the group with symptomatic BRONJ, the outcome was significantly lower (76.4 %). Because of the complex symptoms, close cooperation between oncologists, dentists, and maxillofacial surgeons is required in the treatment of BRONJ. Before starting therapy with bisphosphonates and during the therapy, dental treatment and monitoring of the patient' oral health is necessary.

  20. Osteonecrosis of jaw associated with bisphosphonate use

    PubMed Central

    Rastogi, Ashu; Rattan, Vidya; Bhadada, Sanjay Kumar

    2012-01-01

    Bisphosphonates are associated with osteonecrosis of the jaw (ONJ) that is defined as an area of exposed, nonvital bone in the maxilla or mandible persisting over 6–8 weeks. We describe a case of 55-year-old female who developed ONJ after tooth extraction and had been receiving oral ibandronate for osteoporosis. Diagnosis of ONJ was confirmed on CT scan. The patient was managed conservatively as she denied teriparatide therapy because of cost constraints. PMID:22629519

  1. Toolmarks made by lathe chuck jaws.

    PubMed

    Finkelstein, Nir; Aronson, Ayal; Tsach, Tsadok

    2017-06-01

    This paper presents a forensic method to evidentially tie a workpiece with a specific lathe. Examining using this method can prove or exclude a connection between the two. The importance of this method is mostly due to the growing trend among lawbreakers of manufacturing improvised firearm parts using machining processes. This method is based on comparing jaw impressions made by the chuck on a workpiece. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Removable partial denture with a lateral rotational path of insertion.

    PubMed

    Baharav, H; Ben-Ur, Z; Laufer, B Z; Cardash, H S

    1995-08-01

    A removable partial denture with a lateral path of insertion is useful when unsightly facial clasps are objectional to the patient. Rounded rest seat preparations allow extensions of the minor connector to rotate laterally into embrasure undercuts, providing retention. Guiding planes on the contralateral side ensure a different path of withdrawal from the retentive elements. A Kennedy Class IV arch with a long edentulous span is used to illustrate the denture design.

  3. Laboratory procedures for the one-clasp removable partial denture.

    PubMed

    Ring, M

    1989-05-01

    The lateral rotational path of insertion for removable partial dentures in the Kennedy class II category is generally limited to situations where the dentulous side has been restored with fixed restorations that provide a lingual undercut. The rigid lingual plate is first inserted horizontally into the undercut, followed by a lateral rotation to seat the edentulous side. No alterations of properly designed fixed restorations are necessary. This article discusses the technical procedures in detail.

  4. The characters of Palaeozoic jawed vertebrates

    PubMed Central

    Brazeau, Martin D; Friedman, Matt

    2014-01-01

    Newly discovered fossils from the Silurian and Devonian periods are beginning to challenge embedded perceptions about the origin and early diversification of jawed vertebrates (gnathostomes). Nevertheless, an explicit cladistic framework for the relationships of these fossils relative to the principal crown lineages of the jawed vertebrates (osteichthyans: bony fishes and tetrapods; chondrichthyans: sharks, batoids, and chimaeras) remains elusive. We critically review the systematics and character distributions of early gnathostomes and provide a clearly stated hierarchy of synapomorphies covering the jaw-bearing stem gnathostomes and osteichthyan and chondrichthyan stem groups. We show that character lists, designed to support the monophyly of putative groups, tend to overstate their strength and lack cladistic corroboration. By contrast, synapomorphic hierarchies are more open to refutation and must explicitly confront conflicting evidence. Our proposed synapomorphy scheme is used to evaluate the status of the problematic fossil groups Acanthodii and Placodermi, and suggest profitable avenues for future research. We interpret placoderms as a paraphyletic array of stem-group gnathostomes, and suggest what we regard as two equally plausible placements of acanthodians: exclusively on the chondrichthyan stem, or distributed on both the chondrichthyan and osteichthyan stems. PMID:25750460

  5. [Bisphosphonate-related osteonecrosis of the jaw].

    PubMed

    Atanes-Bonome, P; Atanes-Bonome, A; Ríos-Lage, P; Atanes-Sandoval, A D

    2014-04-01

    The bisphosphonates are stable inorganic pyrophosphate analogs that have demonstrated their efficacy in treatment of osteolytic lesions associated with bony metastases, and multiple myeloma, malignant hypercalcemia, Paget's disease, and osteoporosis. Several publications within the last few years have suggested that osteonecrosis of the jaw is associated with bisphosphonate therapy. The diagnosis and management strategies of the patients with bisphosphonate-related osteonecrosis of the jaw is very difficult. It is important for patients to be informed of the risk of this complication, so that they have the opportunity to assess the need for dental treatment before starting therapy. Preventive measures must be taken before, during, and after treatment with bisphosphonates. If osteonecrosis of the jaw is present, management should be conservative: oral chlorhexidine and antibiotics. Surgical treatment should be reserved for those patients who are symptomatic. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  6. Titanium-zirconium alloy narrow-diameter implants (Straumann Roxolid(®)) for the rehabilitation of horizontally deficient edentulous ridges: prospective study on 18 consecutive patients.

    PubMed

    Chiapasco, M; Casentini, P; Zaniboni, M; Corsi, E; Anello, T

    2012-10-01

    (i) To evaluate the survival and success rates of the new Roxolid narrow diameter implant placed in horizontally deficient ridges; and (ii) to evaluate the incidence of prosthetic complications. In a 24-month period (2009-2010) 18 partially or totally edentulous patients received 51 Straumann Roxolid (13 tissue level, 38 bone level) implants. Prosthetic loading of implants was either immediate (four implants; one patient) or delayed (2-12 months after placement; 47 implants; 17 patients). The patients were rehabilitated with either fixed (16 patients; 45 implants) or removable (two patients; six implants) prostheses. All implants successfully achieved osseointegration and all patients completed the planned prosthetic rehabilitation. Peri-implant bone resorption values ranged from 0 to 1 mm at the end of the observation period (range: 3-19 months). Implant survival and success rates were therefore 100%. No prosthetic complications occurred and all implants are still in function; therefore the prosthesis success rate was 100%. Narrow diameter implants fabricated with the new titanium-zirconium alloy were demonstrated to be reliable in supporting both fixed and removable prosthetic rehabilitations in horizontally deficient ridges. Implant survival, peri-implant bone resorption, and prosthetic complication rates were consistent with those reported in the literature for standard diameter implants placed in non-deficient edentulous ridges. © 2011 John Wiley & Sons A/S.

  7. A Comparative Evaluation of Condylar Guidance Value from Radiograph with Interocclusal Records made During Jaw Relation and Try-in: A Pilot Study.

    PubMed

    Shetty, Shilpa; Satish Babu, C L; Tambake, Deepti; Surendra Kumar, G P; Setpal, Abhishek T

    2013-09-01

    The purpose of this study was to evaluate the reliability of programming the articulator using the radiographs and the interocclusal records made during Jaw relation (Arrow point tracing) and Try-in stage. The study comprised of 15 edentulous subjects with well formed maxillary and mandibular ridges, with no signs and symptoms of temporomandibular joint disorders and neuromuscular disorders. Digital Orthopantomograph was taken for all the subjects. The condylar guidance angles were traced on Orthopantomograph for right and left sides and the values were recorded. The protrusive interocclusal records were made at jaw relation stage and at try-in stage using bite registration paste (Bitrex- vinyl polysiloxane) for all subjects. These interocclusal records were used to programme the Semi-adjustable articulator (Hanau Wide Vue) and the condylar guidance values on the right and left sides were recorded. The condylar guidance values so obtained were compared with the values obtained by Orthopantomograph. The condylar guidance values obtained by the various procedures were subjected to statistical analysis. The results showed statistically significant difference between the condylar guidance values obtained from Orthopantomograph (Radiograph) and the condylar guidance values obtained at the stage of jaw relation and also between Orthopantomograph and condylar guidance values obtained at the stage of Try-in. Condylar guidance values obtained from the Radiographs were higher than those obtained at the stage of Jaw relation and at the stage of Try-in. However, we notice that the mean condylar guidance values obtained at the stage of Try-in were nearer to the mean condylar guidance values obtained on the Radiographs.

  8. The prevalence of craniomandibular disorders in completely edentulous denture-wearing subjects.

    PubMed

    Mercado, M D; Faulkner, K D

    1991-05-01

    A total of 201 completely edentulous subjects taken consecutively from the waiting list of the Royal Dental Hospital of Melbourne were examined. Data were obtained from the dental history and anamnestic and clinical examinations. Analysis revealed that parafunctional habits were prevalent among complete denture wearers, and that elderly complete denture wearers potentially present more signs and symptoms of craniomandibular disorders than do younger subjects.

  9. Two implant overdenture–the first alternative treatment for patients with complete edentulous mandible

    PubMed Central

    Marin, M; Preoteasa, E; Tancu, AM; Preoteasa, CT

    2011-01-01

    Given the increasing life expectancy in the coming years, dental practitioners, as other specialists from different medical fields, will encounter an increasing number of complete edentulous patients. These patients, with a longer active life and higher standards of life quality, will have different expectations for their complete dentures, higher than the standard treatment that uses conventional complete dentures. Two–implant overdenture is considered the first alternative treatment in complete edentulous mandible, according to current medical standards established by a team of specialists in prosthodontics and implantology, and globally known as the McGill Consensus from McGill University, Montreal, Canada. The Consensus was established during a–dayߝand–a–half session of presentations done by experts who presented data, scientific information on the subject, and, not less significant, personal experiences of participants and patients. Overdenture on implants, as an alternative treatment for complete edentulous mandible, has multiple benefits in achieving better conditions of prosthesis: balance and effectiveness, with positive effects on oral structures, aesthetics, and quality of life. Mandibular two–implant overdenture, established as a standard treatment by the highest international forum, should gradually become the first choice of treatment in complete edentulous mandible. PMID:21776308

  10. Treatment of Edentulous Mandibular Fractures with Rigid Internal Fixation: Case Series and Literature Review

    PubMed Central

    Franciosi, Edgardo; Mazzaro, Eduardo; Larranaga, Juan; Rios, Alfredo; Picco, Pedro; Figari, Marcelo

    2014-01-01

    The aim of the study is to analyze the effectiveness of rigid internal fixation (RIF) for treating edentulous mandibular fractures. Because of the low incidence of fractures in edentulous mandible, there is no consensus of the optimal treatment for it. This study included all edentulous patients with mandibular fracture diagnosis, who were treated with internal fixation at the Hospital Italiano de Buenos Aires from November 1991 to July 2011. Data such as age, gender, etiology and location of fracture, surgical approach, type of osteosynthesis used, and postoperative complications were analyzed. A total of 18 patients, 76.2 years mean age, 12 females (66.6%), presented a total of 35 mandibular fractures. The mandibular body was the most common localization of the fractures. Twenty-five fractures received surgical treatment with RIF, mainly approached extraorally. Reconstruction plates were the most common type of fixation used. Fracture reduction was considered satisfactory in 96.5%, with 22.2% of complications and 11.1% of reoperations needed. Open reduction and RIF demonstrated to be a reliable method for treating edentulous mandibular fractures. Nevertheless, there is lack of high-level recommendation publication to support this. PMID:24624255

  11. [Severe periodontitis, edentulism and neuropathy in patients with type 2 diabetes mellitus].

    PubMed

    Menchaca-Díaz, Rufino; Bogarín-López, Bernardo; Zamudio-Gómez, Miguel Alberto; Anzaldo-Campos, María Cecilia

    2012-01-01

    Periodontitis is a frequent pathologic condition in diabetic patient, and has been associated with chronic complications like nephropathy, cardiovascular disease, peripheral artery disease or death. To document the association between severe periodontitis and edentulism with the presence of sensory-motor neuropathy in diabetic patients. Cross-sectional study in type 2 diabetic patients from the family medicine unit no. 27 of the IMSS in Tijuana, México. Patients were evaluated to identify periodontitis and sensory-motor neuropathy. Information was also obtained about sex, age, duration of diabetes, glycemic control, smoking and alcohol use. Four hundred and thirty-six patients completed all measurements. In 180 (41.3%) neuropathy was identified, and associated with age (p < 0.001); duration of diabetes (p < 0.001); fasting glucose (p < 0.001); severe periodontitis (OR: 2.7; IC 95%: 1.5-4.8);and with edentulism (OR: 4.4; IC 95%: 2.0-9.4). Logistic regression multivariable analysis kept as significative the association between severe periodontitis and edentulism with neuropathy (adjusted OR: 1.7; IC 95%: 1.1-2.6). Periodontitis and edentulism are associated with the presence of neuropathy in diabetic patients.

  12. [Preprosthetic surgery of the edentulous maxilla: vestibular deepening with the aid of the CO2 laser].

    PubMed

    Mahler, P; Pouyssegur, V; Rocca, J-P; De Moor, R; Nammour, S

    2009-01-01

    Vestibular deepening for maxillary edentulous patients is mainly indicated once instability cannot be reached due to important bone resorption. Vestibular deepening with CO2 super-pulsed laser enhance, in a bloodless environment, sustentation as well retention of those full dentures in good operative conditions as compared with conventional techniques.

  13. Immediate versus delayed loading of strategic mini dental implants for the stabilization of partial removable dental prostheses: a patient cluster randomized, parallel-group 3-year trial.

    PubMed

    Mundt, Torsten; Al Jaghsi, Ahmad; Schwahn, Bernd; Hilgert, Janina; Lucas, Christian; Biffar, Reiner; Schwahn, Christian; Heinemann, Friedhelm

    2016-07-30

    Acceptable short-term survival rates (>90 %) of mini-implants (diameter < 3.0 mm) are only documented for mandibular overdentures. Sound data for mini-implants as strategic abutments for a better retention of partial removable dental prosthesis (PRDP) are not available. The purpose of this study is to test the hypothesis that immediately loaded mini-implants show more bone loss and less success than strategic mini-implants with delayed loading. In this four-center (one university hospital, three dental practices in Germany), parallel-group, controlled clinical trial, which is cluster randomized on patient level, a total of 80 partially edentulous patients with unfavourable number and distribution of remaining abutment teeth in at least one jaw will receive supplementary min-implants to stabilize their PRDP. The mini-implant are either immediately loaded after implant placement (test group) or delayed after four months (control group). Follow-up of the patients will be performed for 36 months. The primary outcome is the radiographic bone level changes at implants. The secondary outcome is the implant success as a composite variable. Tertiary outcomes include clinical, subjective (quality of life, satisfaction, chewing ability) and dental or technical complications. Strategic implants under an existing PRDP are only documented for standard-diameter implants. Mini-implants could be a minimal invasive and low cost solution for this treatment modality. The trial is registered at Deutsches Register Klinischer Studien (German register of clinical trials) under DRKS-ID: DRKS00007589 ( www.germanctr.de ) on January 13(th), 2015.

  14. A modified occlusal wafer for managing partially dentate orthognathic patients--a case series.

    PubMed

    Soneji, Bhavin Kiritkumar; Esmail, Zaid; Sharma, Pratik

    2015-03-01

    A multidisciplinary approach is essential in orthognathic surgery to achieve stable and successful outcomes. The model surgery planning is an important aspect in achieving the desired aims. An occlusal wafer used at the time of surgery aids the surgeon during correct placement of the jaws. When dealing with partially dentate patients, the design of the occlusal wafer requires modification to appropriately position the jaw. Two cases with partially dentate jaws are presented in which the occlusal wafer has been modified to provide stability at the time of surgery.

  15. Does denture-wearing status in edentulous South Korean elderly persons affect their nutritional intakes?

    PubMed

    Han, Sun Young; Kim, Cheoul Sin

    2016-06-01

    The aim of this cross-sectional study was to determine whether denture-wearing status in edentulous South Korean elders affected their nutritional intakes, using the 2008-2010 data from the Korean National Health and Nutrition Examination Survey (KNHANES). Good nutritional status is a requirement for healthy aging in the elders. Tooth loss is the key to lead to low masticatory ability and alterative food choice, which may increase the risks of systemic disease. Therefore, denture treatment is important to improve general health of edentulous persons. From KNHANES data, 1168 edentulous older people were selected as the participants of the present study. Nutrient intake data collected via participants' 24-h dietary recalls were used to determine the ratio of nutrient intake to the Recommended Dietary Allowance for Koreans, the percentage of individuals with inadequate nutrient and the effects of denture wearing on the risk of undernourishment. The results showed that compared to denture wearers, edentulous persons without dentures had lower intakes of potassium, niacin and vitamin C. In addition, the distribution of inadequate nutrient intake among participants without dentures was higher than among participants with dentures; the risk of undernourishment was 1.89 times that of denture wearers. [Correction made on 21 March 2014, after first online publication: "[…] participants with dentures was higher than among participants without dentures" was corrected to "[…] participants without dentures was higher than among participants with dentures"] Denture wearing was seen to have a significant effect on the level of nutrient intake in edentulous elders. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  16. Nasal mask ventilation is better than face mask ventilation in edentulous patients

    PubMed Central

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. Results: A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients. PMID:27625477

  17. Nasal mask ventilation is better than face mask ventilation in edentulous patients.

    PubMed

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

  18. Edentulism and other variables associated with self-reported health status in Mexican adults.

    PubMed

    Medina-Solís, Carlo Eduardo; Pontigo-Loyola, América Patricia; Pérez-Campos, Eduardo; Hernández-Cruz, Pedro; Avila-Burgos, Leticia; Mendoza-Rodríguez, Martha; Maupomé, Gerardo

    2014-05-23

    To determine if edentulism, controlling for other known factors, is associated with subjective self-report health status (SRH) in Mexican adults. We examined the SRH of 13 966 individuals 35 years and older, using data from the National Survey of Performance Assessment, a cross-sectional study that is part of the technical collaboration between the Ministry of Health of Mexico and the World Health Organization, which used the survey instrument and sampling strategies developed by WHO for the World Health Survey. Sociodemographic, socioeconomic, medical, and behavioral variables were collected using questionnaires. Self-reported health was our dependent variable. Data on edentulism were available from 20 of the 32 Mexican states. A polynomial logistic regression model adjusted for complex sampling was generated. In the SRH, 58.2% reported their health status as very good/good, 33.8% said they had a moderate health status, and 8.0% reported that their health was bad/very bad. The association between edentulism and SRH was modified by age and was significant only for bad/very bad SRH. Higher odds of reporting moderate health or poor/very poor health were found in women, people with lower socio-economic status and with physical disabilities, those who were not physically active, or those who were underweight or obese, those who had any chronic disease, and those who used alcohol. The association of edentulism with a self-report of a poor health status (poor/very poor) was higher in young people than in adults. The results suggest socioeconomic inequalities in SRH. Inequality was further confirmed among people who had a general health condition or a disability. Dentists and health care professionals need to recognize the effect of edentulism on quality of life among elders people.

  19. Morphology and morphometry of the human sublingual glands in mouth floor enlargements of edentulous patients

    PubMed Central

    de SÁ, Josiane Costa Rodrigues; TOLENTINO, Elen de Souza; AZEVEDO-ALANIS, Luciana Reis; IWAKI FILHO, Liogi; LARA, Vanessa Soares; DAMANTE, José Humberto

    2013-01-01

    Asymptomatic mouth floor enlargements may be observed in edentulous patients. These masses, which protrude from the mouth floor, may complicate the fitting of dentures and require surgery. Whether this "entity" may be considered an anatomical variation of the mouth floor or represent specific alterations in the sublingual gland is not known. Objective The aim of this work is to investigate the morphological and morphometric aspects of the sublingual glands of edentulous patients with mouth floor enlargements and compare the glands of these patients with the sublingual glands of human cadavers. Material and Methods Microscopic evaluation was performed on human sublingual glands from edentulous patients with mouth floor enlargements (n=20) and edentulous cadavers (n=20). The patients and cadavers were of similar ages. The data were compared using Mann-Whitney U, Fisher's exact and Student's t tests (p<0.05). Results Acinar atrophy, duct-like structures, mononuclear infiltrates, replacement of parenchyma with fibrous/adipose tissue, mucous extravasation and oncocytosis were similar between the groups (p>0.05). Only the variables "autolysis" and "congested blood vessels" presented statistical difference between groups (p=0.014; p=0.043). The morphometric study revealed that the volume densities of acini, ducts, stroma and adipose tissue were similar between the groups (p>0.05). Conclusion The microscopic characteristics of the sublingual glands in mouth floor enlargements in edentulous patients correspond to characteristics associated with the normal aging process. The glands are not pathological and represent an age-related alteration that occurs with or without the presence of the mouth floor enlargements. PMID:24473720

  20. Morphology and morphometry of the human sublingual glands in mouth floor enlargements of edentulous patients.

    PubMed

    Sá, Josiane Costa Rodrigues de; Tolentino, Elen de Souza; Azevedo-Alanis, Luciana Reis; Iwaki Filho, Liogi; Lara, Vanessa Soares; Damante, José Humberto

    2013-01-01

    Asymptomatic mouth floor enlargements may be observed in edentulous patients. These masses, which protrude from the mouth floor, may complicate the fitting of dentures and require surgery. Whether this "entity" may be considered an anatomical variation of the mouth floor or represent specific alterations in the sublingual gland is not known. The aim of this work is to investigate the morphological and morphometric aspects of the sublingual glands of edentulous patients with mouth floor enlargements and compare the glands of these patients with the sublingual glands of human cadavers. Microscopic evaluation was performed on human sublingual glands from edentulous patients with mouth floor enlargements (n=20) and edentulous cadavers (n=20). The patients and cadavers were of similar ages. The data were compared using Mann-Whitney U, Fisher's exact and Student's t tests (p<0.05). Acinar atrophy, duct-like structures, mononuclear infiltrates, replacement of parenchyma with fibrous/adipose tissue, mucous extravasation and oncocytosis were similar between the groups (p>0.05). Only the variables "autolysis" and "congested blood vessels" presented statistical difference between groups (p=0.014; p=0.043). The morphometric study revealed that the volume densities of acini, ducts, stroma and adipose tissue were similar between the groups (p>0.05). The microscopic characteristics of the sublingual glands in mouth floor enlargements in edentulous patients correspond to characteristics associated with the normal aging process. The glands are not pathological and represent an age-related alteration that occurs with or without the presence of the mouth floor enlargements.

  1. Removable partial denture occlusion.

    PubMed

    Ivanhoe, John R; Plummer, Kevin D

    2004-07-01

    No single occlusal morphology, scheme, or material will successfully treat all patients. Many patients have been treated, both successfully and unsuccessfully, using widely varying theories of occlusion, choices of posterior tooth form, and restorative materials. Therefore, experience has demonstrated that there is no one righ r way to restore the occlusion of all patients. Partially edentulous patients have many and varied needs. Clinicians must understand the healthy physiologic gnathostomatic system and properly diagnose what is or may become pathologic. Henderson [3] stated that the occlusion of the successfully treated patient allows the masticating mechanism to carry out its physiologic functions while the temporomandibular joints, the neuromuscular mechanism, the teeth and their supporting structures remain in a good state of health. Skills in diagnosis and treatment planning are of utmost importance in treating these patients, for whom the clinician's goals are not only an esthetic and functional restoration but also a lasting harmonious state. Perhaps this was best state by DeVan [55] more than 60 years ago in his often-quoted objective. "The patient's fundamental need is the continued meticulous restoration of what is missing, since what is lost is in a sense irretrievably lost." Because it is clear that there is no one method, no one occlusal scheme, or one material that guarantees success for all patients, recommendations for consideration when establishing or reestablishing occlusal schemes have been presented. These recommendations must be used in conjunction with other diagnostic and technical skills.

  2. Eating with a saw for a jaw: functional morphology of the jaws and tooth-whorl in Helicoprion davisii.

    PubMed

    Ramsay, Jason B; Wilga, Cheryl D; Tapanila, Leif; Pruitt, Jesse; Pradel, Alan; Schlader, Robert; Didier, Dominique A

    2015-01-01

    The recent reexamination of a tooth-whorl fossil of Helicoprion containing intact jaws shows that the symphyseal tooth-whorl occupies the entire length of Meckel's cartilage. Here, we use the morphology of the jaws and tooth-whorl to reconstruct the jaw musculature and develop a biomechanical model of the feeding mechanism in these early Permian predators. The jaw muscles may have generated large bite-forces; however, the mechanics of the jaws and whorl suggest that Helicoprion was better equipped for feeding on soft-bodied prey. Hard shelled prey would tend to slip anteriorly from the closing jaws due to the curvature of the tooth-whorl, lack of cuspate teeth on the palatoquadrate (PQ), and resistance of the prey. When feeding on soft-bodied prey, deformation of the prey traps prey tissue between the two halves of the PQ and the whorl. The curvature of the tooth-whorl and position of the exposed teeth relative to the jaw joint results in multiple tooth functions from anterior to posterior tooth that aid in feeding on soft-bodied prey. Posterior teeth cut and push prey deeper into the oral cavity, while middle teeth pierce and cut, and anterior teeth hook and drag more of the prey into the mouth. Furthermore, the anterior-posterior edges of the teeth facilitate prey cutting with jaw closure and jaw depression. The paths traveled by each tooth during jaw depression are reminiscent of curved pathways used with slashing weaponry such as swords and knifes. Thus, the jaws and tooth-whorl may have formed a multifunctional tool for capturing, processing, and transporting prey by cyclic opening and closing of the lower jaw in a sawing fashion.

  3. New insights into dinosaur jaw muscle anatomy.

    PubMed

    Holliday, Casey M

    2009-09-01

    Jaw muscles are key components of the head and critical to testing hypotheses of soft-tissue homology, skull function, and evolution. Dinosaurs evolved an extraordinary diversity of cranial forms adapted to a variety of feeding behaviors. However, disparate evolutionary transformations in head shape and function among dinosaurs and their living relatives, birds and crocodylians, impair straightforward reconstructions of muscles, and other important cephalic soft tissues. This study presents the osteological correlates and inferred soft tissue anatomy of the jaw muscles and relevant neurovasculature in the temporal region of the dinosaur head. Hypotheses of jaw muscle homology were tested across a broad range archosaur and sauropsid taxa to more accurately infer muscle attachments in the adductor chambers of non-avian dinosaurs. Many dinosaurs likely possessed m. levator pterygoideus, a trait shared with lepidosaurs but not extant archosaurs. Several major clades of dinosaurs (e.g., Ornithopoda, Ceratopsidae, Sauropoda) eliminated the epipterygoid, thus impacting interpretations of m. pseudotemporalis profundus. M. pseudotemporalis superficialis most likely attached to the caudoventral surface of the laterosphenoid, a trait shared with extant archosaurs. Although mm. adductor mandibulae externus profundus and medialis likely attached to the caudal half of the dorsotemporal fossa and coronoid process, clear osteological correlates separating the individual bellies are rare. Most dinosaur clades possess osteological correlates indicative of a pterygoideus ventralis muscle that attaches to the lateral surface of the mandible, although the muscle may have extended as far as the jugal in some taxa (e.g., hadrosaurs, tyrannosaurs). The cranial and mandibular attachments of mm adductor mandibulae externus superficialis and adductor mandibulae posterior were consistent across all taxa studied. These new data greatly increase the interpretive resolution of head anatomy in

  4. Bisphosphonates and osteonecrosis of the jaw.

    PubMed

    Shannon, Jodi; Shannon, John; Modelevsky, Steven; Grippo, Anne A

    2011-12-01

    Bisphosphonates are used worldwide as a successful treatment for people with osteoporosis, which is the major underlying cause of fractures in postmenopausal women and older adults. These agents are successful at increasing bone mass and bone trabecular thickness, decreasing the risk of fracture, and decreasing bone pain, enabling individuals to have better quality of life. Bisphosphonates are also used to treat multiple myeloma, bone metastasis, and Paget's disease; however, bisphosphonate treatment may result in negative side effects, including osteonecrosis of the jaw (ONJ). ONJ involves necrotic, exposed bone in the jaw, pain, possible secondary infection, swelling, painful lesions, and various dysesthesias, although less-severe cases may be asymptomatic. First-generation bisphosphonates, which do not contain nitrogen, are metabolized into a nonfunctional, cytotoxic analogue of adenosine triphosphate and cause osteoclast death by starvation. Second-generation bisphosphonates are nitrogen-containing agents; these inhibit osteoclast vesicular trafficking, membrane ruffling, morphology, and cytoskeletal arrangement by inhibiting farnesyl diphosphate synthase in the mevalonate pathway. Physicians treating older adults with osteoporosis and cancer should work together with dental practitioners, pharmacists, and other clinicians to inform individuals receiving bisphosphonates of their possible side effects and to suggest precautionary steps that may minimize the risk of osteonecrosis, particularly of the jaw. These include practicing good oral hygiene; scheduling regular dental examinations and cleanings; and cautioning people who are scheduling treatment for periodontal disease, oral and maxillofacial therapy, endodontics, implant placement, restorative dentistry, and prosthodontics. Recommendations for management of people with ONJ include an oral rinse, such as chlorhexidine, and antibiotics. © 2011, Copyright the Authors Journal compilation © 2011, The American

  5. Dosimetric comparison between jaw tracking and static jaw techniques in intensity-modulated radiotherapy.

    PubMed

    Feng, Zhongsu; Wu, Hao; Zhang, Yibao; Zhang, Yunjun; Cheng, Jinsheng; Su, Xu

    2015-01-27

    To compare the dosimetric differences between jaw tracking technique (JTT) and static jaw technique (SJT) in dynamic intensity-modulated radiotherapy (d-IMRT) and assess the potential advantages of jaw tracking technique. Two techniques, jaw tracking and static jaw, were used respectively to develop the d-IMRT plans for 28 cancer patients with various lesion sites: head and neck, lungs, esophageal, abdominal, prostate, rectal and cervical. The dose volume histograms (DVH) and selected dosimetric indexes for the whole body and for organs at risk (OARs) were compared. A two dimensional ionization chamber Array Seven29 (PTW, Freiburg, Germany) and OCTAVIUS Octagonal phantom (PTW, Freiburg, Germany) were used to verify all the plans. For all patients, the treatment plans using both techniques met the clinical requirements. The V5, V10, V20, V30, V40 (volumes receiving 5, 10, 20, 30 and 40 Gy at least, respectively), mean dose (Dmean) for the whole body and V5, V10, V20, Dmean for lungs in the JTT d-IMRT plans were significantly less than the corresponding values of the SJT d-IMRT plans (p < 0.001). The JTT d-IMRT plans deposited lower maximum dose (Dmax) to the lens, eyes, brainstem, spinal cord, and right optic nerve, the doses reductions for these OARs ranged from 2.2% to 28.6%. The JTT d-IMRT plans deposited significantly lower Dmean to various OARs (all p values < 0.05), the mean doses reductions for these OARs ranged from 1.1% to 31.0%, and the value reductions depend on the volume and the location of the OARs. The γ evaluation method showed an excellent agreement between calculation and measurement for all techniques with criteria of 3%/3 mm. Both jaw tracking and static jaw d-IMRT plans can achieve comparable target dose coverage. JTT displays superior OARs sparing than SJT plans. These results are of clinical importance, especially for the patients with large and complex targets but close to some highly radio-sensitive organs to spare, and for patients

  6. Bisphosphonates and osteonecrosis of the jaw.

    PubMed

    Sambrook, Philip; Olver, Ian; Goss, Alastair

    2006-10-01

    Recently an association between bisphosphonate use and a rare dental condition termed 'osteonecrosis of the jaw' (ONJ) has been reported. Patients with osteoporosis and Paget disease who take bisphosphonates have a significantly reduced risk of fracture and other skeletal complications. This represents significant health benefits, against which the small risk of ONJ needs to be considered. In patients with bone malignancy, the risk of ONJ needs to be balanced against the benefit of therapy on the underlying malignancy. There are still many uncertainties about this condition. This position paper seeks to summarise what is currently known about ONJ to provide information to medical practitioners and dental practitioners.

  7. Thermal resilient multiple jaw braze fixture

    DOEpatents

    Ney, Robert; Perrone, Alex J.

    1995-07-11

    A braze fixture has side walls forming a cavity with an opening to receive a stack of parts to be brazed. Sidewalls of the housing have a plurality of bearing receiving openings into which bearing rods or jaws are inserted to align the stacked elements of the workpiece. The housing can also have view ports to allow a visual check of the alignment. Straps or wires around the fixture are selected to have thermal characteristics similar to the thermal characteristics of the workpiece undergoing brazing. The straps or wires make physical contact with the bearing rods thereby causing bearing rods to maintain the workpiece in proper alignment throughout the entire brazing cycle.

  8. ANN-Models for Jaw-Research

    DTIC Science & Technology

    2007-11-02

    Recently [5], the Peck-Langenbach-Hannam ( PLH ) dynamic model has been developed at U.B.C for the human jaw. It is based on published musculoskele- tal...of Abstract UU Number of Pages 4 Table 1: 3 sets from a 59–set of steady–state measurements of T(m;i) from the PLH simulator. m Set i=1 Set i=2 Set...Training sets can be obtained from the PLH model. The training sets will have special interest be- cause we want the network to generalize by predicting near

  9. Evaluation of Vertical Bone Gain Following Alveolar Distraction Osteogenesis in the Anterior Edentulous Mandible: A Clinical Study.

    PubMed

    Kumar, K A Jeevan; Masrom, Aruna Kishore; Patil, Kapil; Kunusoth, Ramesh; Begum, Farzana; Venkatesh, Veerareddy

    2014-12-01

    To calculate the gain in bony height and volume of the distracted upper segment using an extraosseous unidirectional device to improve the retention of the future prosthesis. Ten cases with completely or partially edentulous but severely or considerably resorbed anterior mandibles were managed by vertical alveolar distraction osteogenesis. All the patients were evaluated preoperatively, intraoperatively and post-operatively for various parameters clinically and radiographically i.e. on OPG, lateral cephalogram and on CT scan, at different time intervals. In all cases there was increase in vertical bone height. The study showed mean vertical bone gain (VBG) on OPG as 8.2 mm. The mean VBG on lateral cephalogram was 8.1 mm. The mean VBG on CT scan at right canine was 8.35 mm, at left canine was 8.2 mm and at midline was 8.27 mm. Alveolar distraction osteogenesis is a predictable method for restoring alveolar ridges prior to implant placement or prosthesis. Distraction osteogenesis is ideally suited for recreating missing tissue in the anterior esthetic zone by increasing vertical bone height as well as good width and soft tissue growth.

  10. Oral health and oral implant status in edentulous patients with implant-supported dental prostheses who are receiving long-term nursing care.

    PubMed

    Isaksson, Rita; Becktor, Jonas P; Brown, Andrew; Laurizohn, Christer; Isaksson, Sten

    2009-12-01

    The aim of this study was to investigate oral health and oral implant status in a group of edentulous patients receiving long-term residential or nursing care (LTC), all of whom had implant-supported fixed or removable dental prostheses. A dental examination was performed on a total of 3310 patients receiving LTC and from this population 35 edentulous patients in whom dental implants had been placed formed the cohort for this study. All examinations were performed by a specialist in hospital dentistry and took place in the patients' own home environment. Oral health was assessed by means of a protocol which evaluated oral hygiene status, possible oral mucosal inflammation and oral mucosal friction levels. Any problems with the implant-supported prosthesis, implant mobility or other complications were also assessed. In addition, patients were asked about any oral symptoms and their usual oral hygiene procedures. About half of the subjects (17/35) were registered as having no/mild inflammation with 18 of 35 having moderate/severe inflammation. Twelve of the 35 patients had good/acceptable oral hygiene and 23 of 35 had poor/bad oral hygiene. Twenty-one of the 35 patients depended on help from the nursing personnel for their daily oral hygiene procedures. Obvious problems with food impaction were noted in 11 patients. A total of 229 implants had been placed in 43 jaws supporting 40 full arch-fixed prostheses and three implant-borne overdentures. There was no evidence of mobility or fractures of either the implants or the prostheses. Fifteen implants showed some exposed screw threads. Pus was exuding from one implant site and general peri-implant gingival hyperplasia was noted in two patients. Twenty-four patients were completely satisfied with the function and appearance of their implant-supported prostheses. Two patients were totally dissatisfied. This study indicates that oral implant therapy can be considered as a treatment of choice in elderly patients, even if

  11. 21 CFR 872.2060 - Jaw tracking device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., while at rest and during jaw movement. (2) Classification. Class I (general controls). The device is... the diagnosis of temporomandibular joint disorders and associated orofacial pain is a nonpowered or... maxilla, while at rest and during jaw movement. The device records, displays, and stores information...

  12. 21 CFR 872.2060 - Jaw tracking device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., while at rest and during jaw movement. (2) Classification. Class I (general controls). The device is... the diagnosis of temporomandibular joint disorders and associated orofacial pain is a nonpowered or... maxilla, while at rest and during jaw movement. The device records, displays, and stores information...

  13. Jaw morphology and fighting forces in stag beetles.

    PubMed

    Goyens, Jana; Dirckx, Joris; Aerts, Peter

    2016-09-15

    The jaws of different species of stag beetles show a large variety of shapes and sizes. The male jaws are used as weapons in fights, and they may exert a very forceful bite in some species. We investigated in 16 species whether and how the forcefulness of their bite is reflected in their jaw morphology. We found a large range of maximal muscle forces (1.8-33 N; factor of 18). Species investing in large bite muscles also have disproportionately large jaw volumes. They use this additional jaw volume to elongate their jaws, increasing their chances of winning in battles. The fact that this also decreases the mechanical advantage is largely compensated for by elongated in-levers. As a result, high muscle forces are correlated with elevated bite forces (0.27-7.6 N; factor of 28). Despite the large difference in the forcefulness of their bite, all investigated species experience similar Von Mises stresses in their jaws while biting (29-114 MPa; factor of 4.0; calculated with finite element simulations). Hence, stag beetles have successfully adapted their jaw anatomy according to their bite force in fights.

  14. Bisphophonates related osteonecrosis of the jaw

    PubMed Central

    Gupta, Swati; Gupta, Hemant; Mandhyan, Devendra; Srivastava, Sanjeev

    2013-01-01

    Objective: With sporadic reporting of BPs related osteonecrosis of jaw and in absence of definitive guidelines regarding the management of such patients, the dentists and the oral and maxillofacial surgeons need to be updated about this issue. The objective of this article was to produce an updated bibliographic review of BPs related ONJ. This paper reviews the literature regarding the same for better understanding of the problem and its management. Background: Bisphosphonates (BPs) are potent inhibitors of bone resorption and are widely used in the treatment of osteoporosis and other diseases that cause bone mass loss, such as Paget's disease, bone metastases, and multiple myeloma, to prevent pathological fractures. With increasing use, evidence is emerging that patients taking BP drugs are at risk of developing osteonecrosis of the jaws (ONJs), sometimes occurring spontaneously, but more commonly following dental extractions or oral bone surgery. Materials and Methods: A bibliographic search was carried out using PubMed, Medline, and search engines ending in April, 2013. The search terms used were: Oral BPs, dental implants, and osteonecrosis. Conclusion: On the basis of available literature, the management of patients on bisphosphonates requiring dental treatment is classified according to the duration of BPs treatment, method of administration of BPs etc. Dental treatments when planned carefully in such patients have a fair to good prognosis. PMID:24665168

  15. Jaw muscles of New World squirrels.

    PubMed

    Ball, S S; Roth, V L

    1995-06-01

    The jaw, suprahyoid, and extrinsic tongue muscles are described for eight species of New World squirrels, spanning more than an order of magnitude in body mass. Anatomical differences are discussed in the light of body size, natural history, and phylogeny. The relative sizes of different muscles, their orientations, and the shapes and positions of their areas of attachment vary but show few trends in relation to body size. The anatomical differences are likewise not readily explained by the mechanical requirements of the animals' diets, which are similar. The most marked anatomical differences occur in Sciurillus (the pygmy tree squirrel), as well as those genera--Glaucomys (the flying squirrel) and Tamias (the chipmunk)--that are taxonomically most distinct from the tree squirrels. Sciurillus is noteworthy for its unusually small temporalis and an anterior deep masseter that is oriented to assist in retraction of the jaw. Tamias has a more vertically oriented temporalis and greater inclination in the anterior masseter muscles than the other squirrels, features that may be associated with its large diastema and relatively posteriorly situated cheek teeth, which in turn may relate to its having cheek pouches. Our results form a valuable database of information to be used in further studies of functional morphology and phylogeny.

  16. On tooth movements and associated tissue alterations related to edentulous areas and bone defects.

    PubMed

    Stokland, Birgitta Lindskog

    2011-01-01

    The aim of the thesis was to study orthodontic tooth movement in relation to edentulous areas and infrabony pockets as well as the physiological movement of teeth facing an edentulous area. A dog model was used in Studies I and II. Teeth were orthodontically moved into and out from inflamed, infrabony periodontal pockets (Study I) and into areas of reduced bone height (Study II). Clinical, radiographic and histometric analyses were made with respect to changes in tooth-supporting tissues. Study III involved clinical, radiographic and 3D model assessments of changes in periodontal conditions and alveolar ridge dimensions in adult patients subjected to tooth movement into areas with reduced ridge dimensions. In Study IV, panoramic radiographs of 292 subjects, taken at an interval of 12 years, were analyzed with regard to changes in the elongation of unopposed molars and tipping of molars facing a mesial edentulous space. In the animal study orthodontic bodily movement of teeth with inflamed, infrabony pockets caused an enhanced rate of progression of the periodontal lesion (Study 1), particularly when the tooth movement was directed towards the infrabony defect. Teeth with healthy periodontium that were orthodontically moved into areas of markedly reduced bone height maintained their periodontal tissue support (Study II). Corresponding orthodontic tooth movement in humans (Study III) resulted in minor dimensional alterations of the periodontal tissues and an increased bucco-lingual width of the alveolar ridge in the area into which the tooth had been moved, whereas a decreased width of the newly established edentulous area was noted. All teeth that were moved showed lateral root resorption at the level of the bone crest on the pressure side, but signs of repair were noticed 1-year post-treatment. In the 12-year radiographic study (Study IV) unopposed molars showed a significant increase in elongation over the 12 years of follow-up. The degree of elongation increased

  17. Changes in jaw-jerk on different levels of jaw closure and teeth-clenching in humans.

    PubMed

    Fukuyama, E; Fujita, Y; Soma, K

    2000-11-01

    We investigated how the jaw-jerk in the human masseter muscle is modulated in relation to the level of jaw closure (JC) and teeth clenching. Electromyographic (EMG) activity was recorded with surface electrodes. Background EMG activity of the masseter muscle was kept at three low teeth clenching levels with visual feedback. The level of JC was changed in six steps along the habitual path of closure relative to the mean maximal jaw opening during gum chewing by inserting a bite block between the upper and lower molars. The jaw-jerk was evoked by applying mechanical stimulation of about 20 N with a hammer to the bite-fork placed on the lower molars on one side in each condition of combination of a level of JC with a level of teeth-clenching. At the resting condition the excitability of the jaw-jerk increased with JC, while at weak voluntary teeth clenching it then decreased and increased again as the jaw was progressively closed. It is suggested that the excitability of the jaw-jerk would increase toward the occlusal position, which in turn would contribute to smooth masticatory movements. In addition, the mode of modulation of the jaw-jerk was studied in a subject with skeletal malocclusion.

  18. Florid cemento-osseous dysplasia: review of an uncommon fibro-osseous lesion of the jaw with important clinical implications.

    PubMed

    Fenerty, Sarah; Shaw, Wei; Verma, Rahul; Syed, Ali B; Kuklani, Riya; Yang, Jie; Ali, Sayed

    2017-05-01

    Florid cemento-osseous dysplasia (FCOD) is a rare, benign, multifocal fibro-osseous dysplastic process affecting tooth-bearing areas of the jaw, characterized by replacement of normal trabecular bone with osseous tissue and dense acellular cementum in a fibrous stroma. It is one clinicopathologic variant in a spectrum of related non-neoplastic fibro-osseous lesions known as cemento-osseous dysplasias (CODs), thought to arise from elements of the periodontal ligament. Diagnosis primarily relies upon radiographic and clinical findings; unnecessary biopsy should be avoided, as inoculation with oral pathogens may precipitate chronic infection in these hypovascular lesions. Appropriate management of uncomplicated FCOD consists of periodic radiographic follow-up. Accordingly, it is important that both radiologists and clinicians performing endodontic interventions possess familiarity with this entity in order to prevent misdiagnosis and inappropriate intervention, which may result in a protracted clinical course. Lesions are usually asymptomatic in the absence of infection, typically discovered on routine dental radiographs or imaging performed for unrelated indications. Radiographically, the condition typically manifests as widespread non-expansile intraosseous masses of varying internal lucency and sclerosis that surround the root apices of vital teeth or edentulous areas in the posterior jaw. While all CODs share similar microscopic features, FCOD is distinguished by its multifocal distribution, involving two or more quadrants of the maxilla and mandible, often in a bilateral symmetric fashion. The vast majority of cases are sporadic, though few exhibit an autosomal dominant familial inheritance pattern. In this pictorial review, we discuss the radiologic characteristics of this entity, pertinent clinical and histologic features, differential diagnoses, and management options.

  19. Power spectrum density analysis for the influence of complete denture on the brain function of edentulous patients - pilot study.

    PubMed

    Perumal, Praveen; Chander, Gopi Naveen; Anitha, Kuttae Viswanathan; Reddy, Jetti Ramesh; Muthukumar, Balasubramanium

    2016-06-01

    This pilot study was to find the influence of complete denture on the brain activity and cognitive function of edentulous patients measured through Electroencephalogram (EEG) signals. The study recruited 20 patients aged from 50 to 60 years requiring complete dentures with inclusion and exclusion criteria. The brain function and cognitive function were analyzed with a mental state questionnaire and a 15-minute analysis of power spectral density of EEG alpha waves. The analysis included edentulous phase and post denture insertion adaptive phase, each done before and after chewing. The results obtained were statistically evaluated. Power Spectral Density (PSD) values increased from edentulous phase to post denture insertion adaption phase. The data were grouped as edentulous phase before chewing (EEG p1-0.0064), edentulous phase after chewing (EEG p2-0.0073), post denture insertion adaptive phase before chewing (EEG p3-0.0077), and post denture insertion adaptive phase after chewing (EEG p4-0.0096). The acquired values were statistically analyzed using paired t-test, which showed statistically significant results (P<.05). This pilot study showed functional improvement in brain function of edentulous patients with complete dentures rehabilitation.

  20. [Preliminary analysis of the bilateral disc-condyle relationship of TMJ before and after prosthetic rehabilitation in edentulous patients].

    PubMed

    Ling, Yue-hua; Shi, Hui-min; Zhao, Jun

    2011-10-01

    To observe the disc-condyle relationship, joint effusion, and osseous abnormalities of the condyle before and after prosthetic rehabilitation in 8 edentulous patients with asymptomatic of bilateral temporomandibular joints (TMJs). Complete dentures of 8 edentulous patients were made. Bilateral TMJ MRI before and after prosthetic rehabilitation was performed to observe TMJ internal changes. Before prosthetic rehabilitation, 10 joint disc displacements were found in 62.5% of 16 TMJs of 8 edentulous patients, including 7 medial disc displacement, 2 lateral disc displacement and anterior disc displacement (6.25%); 7 TMJs had effusion 4 had condylar abnormalities. After prosthetic rehabilitation, 10 disc displacements were found in 16 TMJs of 8 edentulous patients, including 7 medial disc displacement, 2 lateral disc displacement, and 1 anterior disc displacement; 7 TMJs effusion. 4 TMJs had condylar abnormalities. Long-time tooth loss may lead to internal derangement of TMJ in edentulous patients. In short term after prosthetic rehabilitation with complete denture, there is no distinct change in disc-condylar relationship, joint effusion, and condylar abnormalities in edentulous patients.

  1. Power spectrum density analysis for the influence of complete denture on the brain function of edentulous patients - pilot study

    PubMed Central

    Perumal, Praveen; Anitha, Kuttae Viswanathan; Reddy, Jetti Ramesh; Muthukumar, Balasubramanium

    2016-01-01

    PURPOSE This pilot study was to find the influence of complete denture on the brain activity and cognitive function of edentulous patients measured through Electroencephalogram (EEG) signals. MATERIALS AND METHODS The study recruited 20 patients aged from 50 to 60 years requiring complete dentures with inclusion and exclusion criteria. The brain function and cognitive function were analyzed with a mental state questionnaire and a 15-minute analysis of power spectral density of EEG alpha waves. The analysis included edentulous phase and post denture insertion adaptive phase, each done before and after chewing. The results obtained were statistically evaluated. RESULTS Power Spectral Density (PSD) values increased from edentulous phase to post denture insertion adaption phase. The data were grouped as edentulous phase before chewing (EEG p1-0.0064), edentulous phase after chewing (EEG p2-0.0073), post denture insertion adaptive phase before chewing (EEG p3-0.0077), and post denture insertion adaptive phase after chewing (EEG p4-0.0096). The acquired values were statistically analyzed using paired t-test, which showed statistically significant results (P<.05). CONCLUSION This pilot study showed functional improvement in brain function of edentulous patients with complete dentures rehabilitation. PMID:27350852

  2. Augmentation of the rat jaw with autogeneic cortico-cancellous bone grafts and guided tissue regeneration.

    PubMed

    Donos, Nikolaos; Kostopoulos, Lambros; Karring, Thorkild

    2002-04-01

    The aim of the present study was to evaluate the effect of augmenting the maxillary alveolar ridge and the lateral aspect of the mandible with onlay autogeneic cortico-cancellous bone grafts that were covered with e-PTFE membranes. The experiment was carried out in 51 rats. In 15 rats, the edentulous maxillary jaw between the incisor and the first molar was augmented by means of an autogeneic ischiac bone graft that was fixed with a gold-coated microimplant. In one side, the graft was covered with an e-PTFE membrane, while the other side, which served as control, was treated without a membrane. In the other 36 rats, the lateral aspect of the mandible was augmented in both sides by means of an autogeneic ischiac bone graft that was fixed with a gold-coated or a titanium microimplant. In one side, the augmented area was covered with an e-PTFE membrane, while the contralateral side was treated without a membrane. Histological analysis at 60, 120 and 180 days after augmentation of the maxilla showed that, in the case of the test sites (where most of the membranes were either exposed or lost), the bone grafts presented extensive resorption and there was a lack of bone continuity between the graft and the recipient site. Similar findings were made at the non-membrane-treated control sides. In the case of augmentation of the mandible with membranes, the bone grafts were not resorbed, but were integrated into newly formed bone at the recipient site. In the control sides, the grafts presented varying degrees of resorption and integration into the recipient bone. It is concluded that, in comparison to bone grafting alone, onlay ischiac bone grafting combined with guided tissue regeneration eliminates the risk of bone graft resorption and ensures integration of the graft into newly formed bone at the recipient site, provided that closure of the operated area can be maintained during healing.

  3. Temporomandibular Disorders (TMD) in Edentulous Patients: A Review and Proposed Classification (Dr. Bader's Classification).

    PubMed

    Alzarea, Bader K

    2015-04-01

    Temporomandibular disorders (TMD) are a collective term given to a number of clinical problems that involve the masticatory musculature, the temporomandibular joints and associated structures, or both. Although the aetiology of TMD has not been fully understood, in general it is considered to be multifactorial. The signs and symptoms of TMD which present in patients with natural teeth may also occur in edentulous patients. These symptoms may appear in various combinations and degrees. TMD has attained a prominent role within the context of dental care due to its high prevalence. The present paper is a review of the current literature on TMD in edentulous patients; with an attempt to propose a classification for the same.

  4. Temporomandibular Disorders (TMD) in Edentulous Patients: A Review and Proposed Classification (Dr. Bader’s Classification).

    PubMed Central

    2015-01-01

    Temporomandibular disorders (TMD) are a collective term given to a number of clinical problems that involve the masticatory musculature, the temporomandibular joints and associated structures, or both. Although the aetiology of TMD has not been fully understood, in general it is considered to be multifactorial. The signs and symptoms of TMD which present in patients with natural teeth may also occur in edentulous patients. These symptoms may appear in various combinations and degrees. TMD has attained a prominent role within the context of dental care due to its high prevalence. The present paper is a review of the current literature on TMD in edentulous patients; with an attempt to propose a classification for the same. PMID:26023660

  5. [Conceptual approach to classification of implant supported prosthesis for edentulous patients].

    PubMed

    Trezubov, V N; Rozov, R A; Azarin, G S

    2017-01-01

    The aim of this study was the creation of a conceptual model of the standard implant prosthetics for edentulous patients using the data of comprehensive examination and implantation prosthetics in 372 patients aged 38 to 80 years (201 women, 171 men) with 582 implant supported prosthesis of various types, supporting on implants «Nobel Replace Select/Groove» and «Nobel Speedy Groove» (3675 implants). Clinical classification of implant-supported prosthesis for edentulous patients included 5 classes: class 1 (1-2 implants) included 6.2% of implant supported prosthesis, class 2 (3-4 implant) - 19.2% of prostheses, class 3 (5-6 implants) - 30.2% of replacement structures; IV (7-10 implants) - 44%, and V - 0,3%. Restoration class was age-dependent.

  6. Lingualized integration: tooth molds and an occlusal scheme for edentulous implant patients.

    PubMed

    Lang, B R; Razzoog, M E

    1992-01-01

    The interface of bone and soft tissue to dental implants has been extensively documented, while the influence of biomechanics and the occlusal interface continues to be overlooked. Yet that same occlusal interface may ultimately be the prime factor in the lifetime survival rate of dental implants. What is lacking, for the practitioner, is a clear concept of the occlusal rehabilitation which is required and appropriate for the totally edentulous implant patient. Lingualized integration represents an occlusal scheme using specific tooth molds designed to improve the likelihood of maximum intercuspation and an absence of deflective occlusal contacts, provide cusp height for selective occlusal reshaping, and achieve a natural and pleasing appearance. Factors in the articulation and arrangement of the posterior teeth to assure the attainment of the fundamental goals of comfort, function, and appearance in occlusal rehabilitation for edentulous implant patients are included.

  7. A principal components analysis: how pneumatization and edentulism contribute to maxillary atrophy.

    PubMed

    Wagner, F; Dvorak, G; Nemec, S; Pietschmann, P; Figl, M; Seemann, R

    2017-01-01

    The aim of this retrospective cohort study was to investigate the role of sinus pneumatization and residual ridge resorption in maxillary bone loss in 400 computed tomography (CT) scans. In 200 dentate and 200 edentulous patients, both sinuses were analysed using CT scans. The image analysis sequence consisted of manual placement of 24 reference points, followed by automated segmentation and final manual refinement. Finally, a principal components analysis was performed. A total of 788 sinuses were included into the analysis. The edentulous group (98 female: 67.77 ± 11.28 years, 99 male: 65.22 ± 9.87) was significantly older than the group with teeth (99 female: 46.89 ± 16.77 years, 96 male: 49.74 ± 16.2). Female and male patients did not differ regarding age. The alveolar height differed significantly between the groups (edentulous: 7.1 ± 4.3 mm, with teeth: 9.7 ± 4.1 mm), but not between gender (female: 8.3 ± 4.4 mm, male: 8.5 ± 4.4 mm). Principal components analysis was able to explain 90% of the variation in sinus morphology. Prolonged edentulism in the maxillary molar region leads to centripetal and to minor degrees centrifugal ridge resorption. Minor pneumatization occurs in the sinus walls, but the sinus depth underlies the anatomical variation independent of dentition. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Management of a fully edentulous mandible using an implant supported overdenture: a case report.

    PubMed

    Egesi, Edward; Uguru, Chibuzo

    2015-01-01

    The choice for rehabilitation of an edentulous mandible by an implant supported overdenture is now the recommended minimally accepted option. This prosthesis has many advantages over conventional dentures and root or tooth supported overdentuers. We present a case of a failed conventional long span bridge which was treated satisfactorily using a four implant supported over denture and discuss our treatment option along with its advantages. This is a new and developing treatment option in our country.

  9. The Peripheral Giant Cell Granuloma in Edentulous Patients: Report of Three Unique Cases

    PubMed Central

    Etoz, Osman A.; Demirbas, Ahmet Emin; Bulbul, Mehmet; Akay, Ebru

    2010-01-01

    The peripheral giant cell granuloma (PGCG) is a rare reactive exophytic lesion taking place on the gingiva and alveolar ridge usually as a result of local irritating factors such as trauma, tooth extraction, badly finished fillings, unstable dental prosthesis, plaque, calculus, chronic infections, and impacted food. This article presents 3 cases of PGCG that presented at the same location of the edentulous mandible of patients that using complete denture for over ten years. PMID:20613923

  10. Edentulism and other variables associated with self-reported health status in Mexican adults

    PubMed Central

    Medina-Solís, Carlo Eduardo; Pontigo-Loyola, América Patricia; Pérez-Campos, Eduardo; Hernández-Cruz, Pedro; Avila-Burgos, Leticia; Mendoza-Rodríguez, Martha; Maupomé, Gerardo

    2014-01-01

    Background To determine if edentulism, controlling for other known factors, is associated with subjective self-report health status (SRH) in Mexican adults. Material/Methods We examined the SRH of 13 966 individuals 35 years and older, using data from the National Survey of Performance Assessment, a cross-sectional study that is part of the technical collaboration between the Ministry of Health of Mexico and the World Health Organization, which used the survey instrument and sampling strategies developed by WHO for the World Health Survey. Sociodemographic, socioeconomic, medical, and behavioral variables were collected using questionnaires. Self-reported health was our dependent variable. Data on edentulism were available from 20 of the 32 Mexican states. A polynomial logistic regression model adjusted for complex sampling was generated. Results In the SRH, 58.2% reported their health status as very good/good, 33.8% said they had a moderate health status, and 8.0% reported that their health was bad/very bad. The association between edentulism and SRH was modified by age and was significant only for bad/very bad SRH. Higher odds of reporting moderate health or poor/very poor health were found in women, people with lower socio-economic status and with physical disabilities, those who were not physically active, or those who were underweight or obese, those who had any chronic disease, and those who used alcohol. Conclusions The association of edentulism with a self-report of a poor health status (poor/very poor) was higher in young people than in adults. The results suggest socioeconomic inequalities in SRH. Inequality was further confirmed among people who had a general health condition or a disability. PMID:24852266

  11. Measurement of Mucosal Thickness in Denture-bearing Area of Edentulous Mandible

    PubMed Central

    Dong, Jian; Zhang, Fei-Yu; Wu, Guang-Hui; Zhang, Wei; Yin, Jian

    2015-01-01

    Background: The thickness of the alveolar mucosa influences the probability of the occurrence of denture-induced irritations. Thick denture-supporting tissues offer relief from mucosal tenderness and ulcers; however, the uniformity of the thickness across the entire mandibular alveolar mucosa cannot be accurately determined in edentulous patients. This study aimed to assess the mucosal thickness of the denture-bearing area in the edentulous mandible. Methods: Twenty-seven edentulous patients underwent cone-beam computed tomography scanning, wherein the patients wore a record base to retract soft tissues away from the alveolar mucosa. The measured regions were the central incisor (IC), lateral incisor (IL), canine (Ca), first premolar (P1), second premolar (P2), first molar (M1), and second molar (M2) regions. The thickness was measured in the alveolar ridge crest (T), buccal (B1–B4), and lingual (L1–L4) alveolar ridge mucosa. The average thickness of the mucosa at buccal sides (B) and lingual sides (L) were also assessed. Results: The differences in the mucosal thickness between the left and right sides were not significant. In the Ca–M2 regions, T was the thickest, and L3 was the thinnest of all the measured points in the same regions. L was significantly less than B in posterior regions (P < 0.01). On the other hand, M2 at L4 was thinnest of all the measured regions from Ca to M2 (P < 0.01), and was thicker than IC, IL, P1, and P2 at B2. Conclusions: Since the mucosal thickness of denture-bearing area in the edentulous mandible is not uniform; the tissue surface of the denture base or custom tray should be selectively relieved, which may reduce the risk of denture-induced irritations. PMID:25635429

  12. Five-year prospective study of immediate/early loading of fixed prostheses in completely edentulous jaws with a bone quality-based implant system.

    PubMed

    Misch, Carl E; Degidi, Marco

    2003-01-01

    The concept of immediate loading of root-form implants for fixed restorations has received increasing interest over the last 5 years. Several authors have commented on parameters that may influence results, including implant number, implant length, bone density, and patient habits. The trigger for bone remodeling around an implant may occur from the surgical trauma of insertion or the mechanical environment of strain at the interface. In the classic two-stage approach, these were divided episodes, separated by 3 to 6 months. Immediate loading compresses this time frame; the two driving mechanisms for bone repair occur concurrently. A scientific approach to the interface development is to match the bone healing response of trauma (woven bone of repair) to the response of mechanical load (reactive woven bone), so the sum of these two entities does not result in fibrous tissue formation and clinical mobility of the implant. It is the purpose of this article to review the scientific rationale of these statements and coordinate them to bone physiology and bone biomechanics. Findings from previous reports in the literature were reviewed and summarized to form the basis of a prospective study using a bone quality-based implant system (Biohorizons, Maestro Dental Implants, Birmingham, AL, USA). A transitional prosthesis was delivered either on the day of surgery or within 2 weeks for 30 patients and 31 arches. A total of 244 implants were used to support these restorations, for an average of 7.8 implants per prosthesis. After 4 to 7 months, the final restorations were fabricated. One year after the final restoration was loaded, the implant survival was 100%; the 31 restorations also had a survival of 100% over this time frame. This report presents these implants and restorations over a 1- to 5-year period, with an average follow-up period of 2.6 years. The bone loss from implant insertion to final prosthesis delivery averaged 0.7 mm. The first-year bone loss after final prosthesis delivery averaged 0.07 mm. A slight increase in bone height was observed after the first year, but generally no increase was observed over the remaining evaluation period. In the current report, no implant failure occurred, and crestal bone loss values were similar to or less than values reported with the conditional two-stage approach. This may be related to the number and position of implants, implant design, and/or the surface condition of the implant loading.

  13. A Survey of the Knowledge of Dental Implants as a Choice in Treatment of Edentulous Jaws among Health Workers in Government Dental Clinics in Enugu

    PubMed Central

    Mgbeokwere, U; Okoye, L; Ekwueme, O

    2011-01-01

    Background: Dental implantology is fast becoming a specialty in the field of dentistry. Within the last five decades, dentistry appears to have recorded its most significant advancement in the field of dental implantology. With dental implants, missing teeth can now be replaced with stable, comfortable and natural-looking and feeling artificial replacements. Inspite of this lenght of time associated with the innovation, the awareness and practice of dental implantology in the government dental clinics in Enugu is still aground. Objectives: To determine if health workers in these hospitals were aware of dental implants as a choice for replacing missing teeth. Methods: The survey was conducted using a random sampling with self-administered questionnaires among health workers in the three health institutions in Enugu between January and February, 2009. Results: Out of 320 respondents in the study, only 31 (9.7%) were aware of dental implant, while 23( 7.2% ) recognised it as a choice in tooth replacement. Conclusion: The knowledge of dental implants as a replacement choice for missing dentitions is low among health workers in Enugu. PMID:23209960

  14. Analysis of jaw movements and muscle activity during mastication with JawReports Software.

    PubMed

    John, D; Ruge, S; Kordass, B

    2011-01-01

    We are currently developing new software for simultaneous visualisation and analysis of computerized recorded masticatory function and masticatory muscle activity. With the software, motion data recorded using the Jaw Motion Analyser and EMG data on masseter muscle activity can be uploaded in order to evaluate chewing activity immediately proximal to the occlusal surfaces. The software successfully differentiated between jaw opening and closing movements and filtered out muscle activity peaks, which were graphically depicted in the respective movement trajectories. This tracking strategy made it possible to visualize the movement sectors where chewing forces were effective and to estimate the strength of these forces. In the future, this software should improve our ability to analyze and assess the development of chewing forces. Therefore, it could provide a tool for optimal planning of implant-supported or CAD/CAM restorations.

  15. Complete denture wearing and fractures among edentulous patients treated in university clinics.

    PubMed

    Takamiya, Aline S; Monteiro, Douglas R; Marra, Juliê; Compagnoni, Marco A; Barbosa, Debora B

    2012-06-01

    The prevalence of wearing and fracture of complete dentures was evaluated among edentulous patients treated in two dental schools in Brazil. Acceptance and wearing of complete dentures are related to adaptive behaviour of edentulous patients. However, one reason that could interfere with the wearing dentures is their potential to fracture, which is still a common complication in denture rehabilitation practice. Two hundred and twenty-four edentulous patients rehabilitated with complete dentures from 2000 to 2005 in Araçatuba and Araraquara Dental School, University of State of São Paulo, were assessed in 2006 and 2007 to answer a questionnaire about wearing and fracture of their dentures. Statistical analysis were performed using Epi Info software and chi-squared test to compare maxillary and mandibular data (α = 0.05). Almost 26% of the patients did not wear their dentures, and among the remainder, the majority wore the maxillary denture. About 30% of the dentures were fractured, with higher prevalence in the maxillary arch (p = 0.003). Discontinuation of wearing dentures was quite high, especially considering the treatment which was carried out in university clinics. Prevalence of fractures was also high, greater for the maxillary denture, and was one of the main reasons for non-wearing of complete dentures. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

  16. Impacts of wearing complete dentures on bolus transport during feeding in elderly edentulous.

    PubMed

    Yamamoto, H; Furuya, J; Tamada, Y; Kondo, H

    2013-12-01

    Prosthetic treatment with dentures is often required for the elderly who have reduced swallowing function. Therefore, it is important to understand the relationship between denture-wearing and feeding function from the perspective of swallowing. To clarify changes in bolus transport during feeding in elderly edentulous patients with or without complete dentures. Subjects were 15 elderly edentulous volunteers who were treated with maxillary and mandibular complete dentures. The test food was 10 g of minced agar jelly containing barium sulphate with a particle diameter of 4·0-5·6 mm. Lateral videofluoroscopy was performed to assess the position of the leading edge of the bolus, the bolus volume in each area at swallow onset, bolus transit time and the mandibular position during pharyngeal swallowing. There were significant changes between the bolus transport with and without dentures. Without dentures, the leading edge of the bolus at swallow onset fell from the valleculae area to the hypopharynx, and the bolus volume in the hypopharynx increased. Bolus transit time increased in the oral cavity, valleculae and hypopharynx. The mandibular position shifted anterosuperior direction. The results arose owing to anatomical changes in the oral and pharyngeal structure and the following functional changes: poor food manipulation, poor bolus formation and delayed swallowing reflex. Removing dentures in elderly edentulous individuals influences bolus transport during feeding, resulting in the exacerbation of the reduced swallowing reserve capacity that accompanies ageing, and may increase the risk of dysphagia. © 2013 John Wiley & Sons Ltd.

  17. Fixed implant-retained rehabilitation of the edentulous maxilla: 11-year results of a prospective study.

    PubMed

    Mertens, Christian; Steveling, Helmut G; Stucke, Kathrin; Pretzl, Bernadette; Meyer-Bäumer, Amelie

    2012-12-01

    The aim of the present study was to assess long-term survival and success rates of implants in the edentulous maxilla restored with an implant-supported fixed prosthesis. Seventeen edentulous patients received six to eight implants and implant-supported fixed prostheses by one surgeon. Yearly recalls were conducted by two examiners over a period of 11 years. Survival and success rates (biological complications) were determined; marginal bone loss was examined radiographically. Furthermore, microbiological tests as well as test for interleukin-1 composite genotype were assessed and potential risk factors were evaluated. After a mean time of 11.26 years, 15 patients of 17 could be reexamined. Out of 94 implants, three were lost in one patient. Mean marginal bone loss reached 0.88 mm, two patients (at seven implants) showed bone loss of ≥3.2 mm. Survival rate of implants reached 96.8%. Success rates on implant level hit 92.6% according to the criteria of Albrektsson and colleagues and 83.0% in accordance with Karoussis and colleagues. One prosthesis had to be renewed. Within the limitation of this study, restoration of the edentulous maxilla with an implant-supported fixed prosthesis represents an effective tool for rehabilitation over a period of 11 years. © 2012 Wiley Periodicals, Inc.

  18. Implant-Retained Obturator for an Edentulous Patient with a Hemimaxillectomy Defect Complicated with Microstomia

    PubMed Central

    2016-01-01

    Patient. A 68-year-old man was operated on for squamous cell carcinoma (T3N3M0) of the maxilla creating the hemimaxillary surgical defect on right side. The remaining arch was completely edentulous. There was remarkable limitation in the oral opening with reduced perimeter of the oral cavity due to radiation and surgical scar contracture. This article describes prosthetic rehabilitation by modifying the design of the obturator and achieving the retention with dental implant. Discussion. Severe limitation in the oral opening may occur in clinical situations following the postsurgical management of oral and maxillofacial defects. The prosthetic rehabilitation of the surgical defect in such patients becomes a challenging task due to limited access to the oral cavity. This challenge becomes even more difficult if the patient is edentulous and there are no teeth to gain the retention, stability, and support. Conclusion. In severe microstomia prosthesis insertion and removal can be achieved with modification of the maximum width of the prosthesis. Dental implant retention is useful treatment option in edentulous patients with maxillary surgical defect provided that sufficient bone volume and accessibility are there for implant placement. PMID:27843652

  19. [Bisphosphonate and osteonecrosis of the jaw.

    PubMed

    Taguchi, Akira

    Marx first reported avascular osteonecrosis of the jaw(ONJ)in oncology patients who had used high dose intravenous bisphosphonate(BP)at 2003. Ruggiero et al. also reported BP-related ONJ in osteoporosis patients who had used low dose oral BP at 2004. Since tooth extraction was considered one of risk factors for ONJ, discontinuation of BP before and after tooth extraction was recommended as one of preventive strategy for ONJ, especially in osteoporosis patients. However, recent studies showed that discontinuation of BP did not prevent ONJ, but increased the occurrence of adverse events such as fracture. Best strategies for preventing ONJ include elimination of oral disease such as periodontal and/or periapical diseases prior to initiation of BP, as well as maintenance of good oral hygiene. Development of a strategy for sharing information about ONJ among physicians, dentists, and patients is required to reduce the incidence of ONJ.

  20. Thermal resilient multiple jaw braze fixture

    DOEpatents

    Ney, R.; Perrone, A.J.

    1995-07-11

    A braze fixture has side walls forming a cavity with an opening to receive a stack of parts to be brazed. Sidewalls of the housing have a plurality of bearing receiving openings into which bearing rods or jaws are inserted to align the stacked elements of the workpiece. The housing can also have view ports to allow a visual check of the alignment. Straps or wires around the fixture are selected to have thermal characteristics similar to the thermal characteristics of the workpiece undergoing brazing. The straps or wires make physical contact with the bearing rods thereby causing bearing rods to maintain the workpiece in proper alignment throughout the entire brazing cycle. 9 figs.

  1. [A comparative study on the responses of blood vessels of oral mucosa to thermal stimulation in dentulous and edentulous subjects].

    PubMed

    Naitoh, T; Torii, K; Kobayashi, Y

    1989-08-01

    The purpose of this experiment was to clarify the characteristic changes of vasculature in edentulous alveolar mucosa and the effect of wearing a complete denture during sleep. Thermal stimulations were applied to the oral mucosa of five normal subjects and five completely edentulous patients and the responses of blood vessels were observed using both Impedance Plethysmography (IMP) and Reflection Photoelectric Plethysmography (RPP). Quantitative comparisons were made between edentulous patients and dentulous normal subjects, and between patients wearing complete dentures during sleep and those who do not. The following results were obtained. 1) The responses of blood vessels were divided into four groups. Type 1 showed dilatation in IMP and RPP. Type 2 showed dilatation but had late initial rising in IMP. Type 3 showed initial contraction in either or both IMP and RPP, and followed by dilatation few seconds later. Type 4 showed no changes in RPP but dilatation in IMP. 2) There was definite difference between edentulous and dentulous subjects in the frequency of exhibition of each type. Especially for the edentulous patients type 4 was observed in all stimulation temperature. 3) For the dentulous subjects there were more cases showing responses of RPP in digital apex than those do not. This was most conspicuous at the 50 degrees C stimulation. However for the edentulous patients there were about equal number of each cases. 4) The responses of blood vessels for both dentulous and edentulous subjects became greater and blood volume increased both with time at each temperature and as the stimulation temperature were raised. However the increase in the response was greater for the edentulous patients when the stimulation temperature was raised from 0 degrees C to 50 degrees C. 5) The responses of blood vessels became greater after two weeks when complete dentures were worn during sleep at night. And when dentures were not worn during sleep the responses decreased to a

  2. Flexible thermoplastic denture base materials for aesthetical removable partial denture framework.

    PubMed

    Singh, Kunwarjeet; Aeran, Himanshu; Kumar, Narender; Gupta, Nidhi

    2013-10-01

    Conventional fixed partial dentures, implant supported Fixed Partial Dentures (FDPs) and removable partial dentures are the most common treatment modalities for the aesthetic and functional rehabilitation of partially edentulous patients. Although implants and FDP have certain advantages over removable partial dentures, in some cases, removable partial dentures may be the only choice which is available. Removable cast partial dentures are used as definitive removable prostheses when indicated, but location of clasps may affect aesthetics. So, when patient is concerned about aesthetics, flexible partial dentures which is aesthetically superior to flipper and cast partial dentures, may be considered. But for the success of flexible removable partial denture, proper diagnosis, treatment planning and insertion technique of this prosthesis is very important, which have been thoroughly described in this article.

  3. Implants (3.3 mm diameter) for the rehabilitation of edentulous posterior regions: a retrospective clinical study with up to 11 years of follow-up.

    PubMed

    Maló, Paulo; de Araújo Nobre, Miguel

    2011-06-01

    There is limited evidence for the use of narrow-diameter implants for rehabilitation of the posterior regions of the jaws using different surgical techniques. The purpose of this study was to report the clinical results of implant-supported prosthetic rehabilitations in the posterior regions of both jaws, using narrow-diameter implants. The study included 147 patients (115 males and 32 females), with an age range of 26 to 77 years (mean = 47.5 years), with a total of 247 implants inserted and followed between 1 and 11 years, with a median follow-up time of 5 years. The patients were in need of fixed prosthetic implant-supported rehabilitations in the posterior region of the jaw, presenting a reduced interradicular bone or a thin alveolar crest. The implant survival estimate was computed using the Kaplan-Meier product limit estimator. The survival rate for narrow diameter implants was 95.1% at 11 years (Kaplan-Meier), with a distribution of 91.4% at 11 years, 95.9% at 10 years, and 95.5% at 9 years for the two-stage, one-stage, and immediate function techniques, respectively. The mean marginal bone resorption recorded at 1, 5, and 10 years were 1.16, 1.53, and 1.74 mm, respectively. Backward conditional logistic regression identified "type of implant" as a strong protective factor against implant failure (MkIII and NobelSpeedy implants compared to the MkII implant; OR = 0.14), and "type of rehabilitation" as a strong risk factor for implant failure (partial rehabilitations compared to single teeth rehabilitations; OR = 4.75). The results indicate that within the limitations of this study, the use of narrow-diameter implants for the prosthetic rehabilitation of posterior regions of the jaws is viable, with good outcomes in the long-term, irrespective of the surgical technique implemented. © 2009 Wiley Periodicals, Inc.

  4. Age, period, and cohort analysis of regular dental care behavior and edentulism: A marginal approach

    PubMed Central

    2011-01-01

    Background To analyze the regular dental care behavior and prevalence of edentulism in adult Danes, reported in sequential cross-sectional oral health surveys by the application of a marginal approach to consider the possible clustering effect of birth cohorts. Methods Data from four sequential cross-sectional surveys of non-institutionalized Danes conducted from 1975-2005 comprising 4330 respondents aged 15+ years in 9 birth cohorts were analyzed. The key study variables were seeking dental care on an annual basis (ADC) and edentulism. For the analysis of ADC, survey year, age, gender, socio-economic status (SES) group, denture-wearing, and school dental care (SDC) during childhood were considered. For the analysis of edentulism, only respondents aged 35+ years were included. Survey year, age, gender, SES group, ADC, and SDC during childhood were considered as the independent factors. To take into account the clustering effect of birth cohorts, marginal logistic regressions with an independent correlation structure in generalized estimating equations (GEE) were carried out, with PROC GENMOD in SAS software. Results The overall proportion of people seeking ADC increased from 58.8% in 1975 to 86.7% in 2005, while for respondents aged 35 years or older, the overall prevalence of edentulism (35+ years) decreased from 36.4% in 1975 to 5.0% in 2005. Females, respondents in the higher SES group, in more recent survey years, with no denture, and receiving SDC in all grades during childhood were associated with higher probability of seeking ADC regularly (P < 0.05). The interaction of SDC and age (P < 0.0001) was significant. The probabilities of seeking ADC were even higher among subjects with SDC in all grades and aged 45 years or older. Females, older age group, respondents in earlier survey years, not seeking ADC, lower SES group, and not receiving SDC in all grades were associated with higher probability of being edentulous (P < 0.05). Conclusions With the use of GEE

  5. Molecular decay of enamel matrix protein genes in turtles and other edentulous amniotes

    PubMed Central

    2013-01-01

    Background Secondary edentulism (toothlessness) has evolved on multiple occasions in amniotes including several mammalian lineages (pangolins, anteaters, baleen whales), birds, and turtles. All edentulous amniote clades have evolved from ancestors with enamel-capped teeth. Previous studies have documented the molecular decay of tooth-specific genes in edentulous mammals, all of which lost their teeth in the Cenozoic, and birds, which lost their teeth in the Cretaceous. By contrast with mammals and birds, tooth loss in turtles occurred in the Jurassic (201.6-145.5 Ma), providing an extended time window for tooth gene degradation in this clade. The release of the painted turtle and Chinese softshell turtle genomes provides an opportunity to recover the decayed remains of tooth-specific genes in Testudines. Results We queried available genomes of Testudines (Chrysemys picta [painted turtle], Pelodiscus sinensis [Chinese softshell turtle]), Aves (Anas platyrhynchos [duck], Gallus gallus [chicken], Meleagris gallopavo [turkey], Melopsittacus undulatus [budgerigar], Taeniopygia guttata [zebra finch]), and enamelless mammals (Orycteropus afer [aardvark], Choloepus hoffmanni [Hoffmann’s two-toed sloth], Dasypus novemcinctus [nine-banded armadillo]) for remnants of three enamel matrix protein (EMP) genes with putative enamel-specific functions. Remnants of the AMBN and ENAM genes were recovered in Chrysemys and retain their original synteny. Remnants of AMEL were recovered in both testudines, although there are no shared frameshifts. We also show that there are inactivated copies of AMBN, AMEL and ENAM in representatives of divergent avian lineages including Galloanserae, Passeriformes, and Psittaciformes, and that there are shared frameshift mutations in all three genes that predate the basal split in Neognathae. Among enamelless mammals, all three EMP genes exhibit inactivating mutations in Orycteropus and Choloepus. Conclusions Our results highlight the power of

  6. Molecular decay of enamel matrix protein genes in turtles and other edentulous amniotes.

    PubMed

    Meredith, Robert W; Gatesy, John; Springer, Mark S

    2013-01-23

    Secondary edentulism (toothlessness) has evolved on multiple occasions in amniotes including several mammalian lineages (pangolins, anteaters, baleen whales), birds, and turtles. All edentulous amniote clades have evolved from ancestors with enamel-capped teeth. Previous studies have documented the molecular decay of tooth-specific genes in edentulous mammals, all of which lost their teeth in the Cenozoic, and birds, which lost their teeth in the Cretaceous. By contrast with mammals and birds, tooth loss in turtles occurred in the Jurassic (201.6-145.5 Ma), providing an extended time window for tooth gene degradation in this clade. The release of the painted turtle and Chinese softshell turtle genomes provides an opportunity to recover the decayed remains of tooth-specific genes in Testudines. We queried available genomes of Testudines (Chrysemys picta [painted turtle], Pelodiscus sinensis [Chinese softshell turtle]), Aves (Anas platyrhynchos [duck], Gallus gallus [chicken], Meleagris gallopavo [turkey], Melopsittacus undulatus [budgerigar], Taeniopygia guttata [zebra finch]), and enamelless mammals (Orycteropus afer [aardvark], Choloepus hoffmanni [Hoffmann's two-toed sloth], Dasypus novemcinctus [nine-banded armadillo]) for remnants of three enamel matrix protein (EMP) genes with putative enamel-specific functions. Remnants of the AMBN and ENAM genes were recovered in Chrysemys and retain their original synteny. Remnants of AMEL were recovered in both testudines, although there are no shared frameshifts. We also show that there are inactivated copies of AMBN, AMEL and ENAM in representatives of divergent avian lineages including Galloanserae, Passeriformes, and Psittaciformes, and that there are shared frameshift mutations in all three genes that predate the basal split in Neognathae. Among enamelless mammals, all three EMP genes exhibit inactivating mutations in Orycteropus and Choloepus. Our results highlight the power of combining fossil and genomic evidence

  7. Jaw-muscle architecture and mandibular morphology influence relative maximum jaw gapes in the sexually dimorphic Macaca fascicularis.

    PubMed

    Terhune, Claire E; Hylander, William L; Vinyard, Christopher J; Taylor, Andrea B

    2015-05-01

    Maximum jaw gape is a performance variable related to feeding and non-feeding oral behaviors, such as canine gape displays, and is influenced by several factors including jaw-muscle fiber architecture, muscle position on the skull, and jaw morphology. Maximum gape, jaw length, and canine height are strongly correlated across catarrhine primates, but relationships between gape and other aspects of masticatory apparatus morphology are less clear. We examine the effects of jaw-adductor fiber architecture, jaw-muscle leverage, and jaw form on gape in an intraspecific sample of sexually dimorphic crab-eating macaques (Macaca fascicularis). As M. fascicularis males have relatively larger maximum gapes than females, we predict that males will have muscle and jaw morphologies that facilitate large gape, but these morphologies may come at some expense to bite force. Male crab-eating macaques have relatively longer jaw-muscle fibers, masseters with decreased leverage, and temporomandibular joint morphologies that facilitate the production of wide gapes. Because relative canine height is correlated with maximum gape in catarrhines, and males have relatively longer canines than females, these results support the hypothesis that male M. fascicularis have experienced selection to increase maximum gape. The sexes do not differ in relative masseter physiologic cross-sectional area (PCSA), but males compensate for a potential trade-off between muscle excursion versus muscle force with increased temporalis weight and PCSA. This musculoskeletal configuration is likely functionally significant for behaviors involving aggressive canine biting and displays in male M. fascicularis and provides additional evidence supporting the multifactorial nature of the catarrhine masticatory apparatus. Our results have implications for the evolution of craniofacial morphology in catarrhine primates and reinforce the importance of evaluating additional factors other than feeding behavior and diet

  8. Motor control of jaw muscles in chewing and in isometric biting with graded narrowing of jaw gape.

    PubMed

    Pröschel, P A; Jamal, T; Morneburg, T R

    2008-10-01

    When a certain bite force is applied during unilateral chewing, the combination of jaw elevator muscle activities is different than when a comparable force is applied in unilateral isometric biting, e.g. on a force transducer. Masticatory peak force is generated in a nearly isometric phase of the chewing cycle, with a jaw gape of about 1 mm. In contrast, peak force in isometric biting on force measuring equipment usually induces jaw gapes of 6 mm or even more. Therefore, we tested the hypothesis that the jaw gape influences relative activation of elevator muscles in unilateral isometric biting. We further examined whether such influence could explain the different activity combinations of chewing and isometric biting. In thirty asymptomatic males, masseter and temporalis activities were recorded during intermittent isometric biting with jaw gapes of 6, 5, 3, 2 and 1 mm and during unilateral chewing. Activity combinations were described by working/balancing ratios and by temporalis/masseter ratios. With decreasing jaw gape the working/balancing ratio of the posterior temporalis decreased (P < 0.002) while that of the masseter increased (P < 0.001). Likewise, the temporalis/masseter ratio on the balancing side increased (P < 0.001). With decreasing jaw gape, activity ratios of isometric biting approached ratios of chewing. We conclude that: (i) relative jaw muscle activation in isometric biting depends on the jaw gape, (ii) relative muscle activation in chewing resembles relative activation of isometric biting with a small 'chewing-like' gape. This suggests that characteristic activity combinations in chewing are mainly a result of the approximately isometric contraction during the slow closing phase of the chewing cycle.

  9. Telescopic Overdenture and Implant Supported Fixed Partial Denture: A Pragmatic Treatment Approach

    PubMed Central

    Dede, Doğu Ömür; Cenk Durmuşlar, M.; Şahın, Onur; Köroğlu, Ayşegül; İşısağ, Özer

    2015-01-01

    This case report presents a patient who had been rehabilitated with a telescopic overdenture and implant supported fixed partial denture (ISFPD). The treatment process was as follows: (1) fabricating telescopic crowns and overdenture prosthesis for the lower jaw and a temporary complete denture for the upper jaw, (2) using the temporary denture as diagnostic and surgical guide to optimize dental implant placement, and (3) fabricating ISFPD for the upper jaw. Using the patient's existing or temporary denture not only serves as an alternative surgical guide to calibrate the dental implant locations but also helps to finish the restoration at desired dimension, size, and anatomic form. PMID:26106491

  10. 33. DETAIL VIEW LOOKING DOWN AT THE BLAKE JAW CRUSHER. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. DETAIL VIEW LOOKING DOWN AT THE BLAKE JAW CRUSHER. NOT THE IDLER PULLEYS AND THE PULLEYS AD SHAFT OF THE POWER SYSTEM OVERHEAD. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  11. Bisphosphonates and osteonecrosis of the jaws: science and rationale.

    PubMed

    Gutta, Rajesh; Louis, Patrick J

    2007-08-01

    Bisphosphonates as a group of drugs were introduced for the management of various conditions such as osteoporosis, Paget's disease, multiple myeloma, hypercalcemia of malignancy, breast cancer, prostate cancer, and other tumors. This group of drugs has improved the quality of life in many patients with proven efficacy in limiting pain and skeletal-related events. The controversy of osteonecrosis of the jaws and bisphosphonates is a recent and growing problem. Osteonecrosis of the jaws is recognized as a serious complication of bisphosphonate therapy, more commonly with the intravenous form of the drugs. However, there is limited scientific understanding about the association between osteonecrosis of the jaws and bisphosphonates. In the present article we discuss various mechanisms of action of bisphosphonates, the rationale for occurrence of osteonecrosis in the jaws, and treatment guidelines for the condition.

  12. Dependence of jaw opening on pitch and vowel in singers.

    PubMed

    Sundberg, J; Skoog, J

    1997-09-01

    In singing, F0 sometimes is much higher than the typical frequency value of F1. According to previous investigations, sopranos raise F1 to a frequency near F0 by widening the jaw opening in such cases. In the present study, the jaw opening was measured in 10 professional singers of different categorizations whose task was to sing an ascending two-octave scale on different vowels. Their normal F1 values for these vowels were determined at a low F0. Only for the vowels /a/ and /a/ did the singers widen the jaw opening when F0 approached the F1 value measured at a low pitch. For the other vowels, jaw opening was widened, beginning at a higher F0. It is assumed that for these vowels the singers used other articulatory means to increase F1.

  13. [Relationship between osteonecrosis of the jaw and bisphosphonate treatment].

    PubMed

    Badel, Tomislav; Keros, Jadranka; Krapac, Ladislav; Pavicin, Ivana Savić

    2010-09-01

    Bisphosphonate treatment and its aetiopathogenic association with aseptic osteonecrosis of the jaw is one of the more prominent public health issues today. The aim of this review is to see into the mechanisms of bisphosphonate effects on bones described in literature (anti-osteoclastic activity, cytotoxicity, antiangiogenesis, genetic factors, and imbalance between osteoclasts and osteoblasts). Bisphosphonate treatment is the dominant cause of jaw necrosis. Epidemiological data show an exclusive incidence of osteonecrosis of the jaw in patients who took one or a combination of nitrogen-containing bisphosphonates. Risk factors vary by the bisphosphonate potency (particularly risky are the highly potent pamidronate and zoledronate, which are given intravenously), dosage, duration of treatment, and the illness. Jaw necrosis is most common in oncology patients, and only 5 % in patients with osteoporosis. From a dental-medical point of view, a good oral health is important because osteonecrosis often appears after a periodontal or oral surgical procedure.

  14. Monte Carlo-based simulation of dynamic jaws tomotherapy

    SciTech Connect

    Sterpin, E.; Chen, Y.; Chen, Q.; Lu, W.; Mackie, T. R.; Vynckier, S.

    2011-09-15

    Purpose: Original TomoTherapy systems may involve a trade-off between conformity and treatment speed, the user being limited to three slice widths (1.0, 2.5, and 5.0 cm). This could be overcome by allowing the jaws to define arbitrary fields, including very small slice widths (<1 cm), which are challenging for a beam model. The aim of this work was to incorporate the dynamic jaws feature into a Monte Carlo (MC) model called TomoPen, based on the MC code PENELOPE, previously validated for the original TomoTherapy system. Methods: To keep the general structure of TomoPen and its efficiency, the simulation strategy introduces several techniques: (1) weight modifiers to account for any jaw settings using only the 5 cm phase-space file; (2) a simplified MC based model called FastStatic to compute the modifiers faster than pure MC; (3) actual simulation of dynamic jaws. Weight modifiers computed with both FastStatic and pure MC were compared. Dynamic jaws simulations were compared with the convolution/superposition (C/S) of TomoTherapy in the ''cheese'' phantom for a plan with two targets longitudinally separated by a gap of 3 cm. Optimization was performed in two modes: asymmetric jaws-constant couch speed (''running start stop,'' RSS) and symmetric jaws-variable couch speed (''symmetric running start stop,'' SRSS). Measurements with EDR2 films were also performed for RSS for the formal validation of TomoPen with dynamic jaws. Results: Weight modifiers computed with FastStatic were equivalent to pure MC within statistical uncertainties (0.5% for three standard deviations). Excellent agreement was achieved between TomoPen and C/S for both asymmetric jaw opening/constant couch speed and symmetric jaw opening/variable couch speed, with deviations well within 2%/2 mm. For RSS procedure, agreement between C/S and measurements was within 2%/2 mm for 95% of the points and 3%/3 mm for 98% of the points, where dose is greater than 30% of the prescription dose (gamma analysis

  15. Evolutionary Trends in the Jaw Adductor Mechanics of Ornithischian Dinosaurs.

    PubMed

    Nabavizadeh, Ali

    2016-03-01

    Jaw mechanics in ornithischian dinosaurs have been widely studied for well over a century. Most of these studies, however, use only one or few taxa within a given ornithischian clade as a model for feeding mechanics across the entire clade. In this study, mandibular mechanical advantages among 52 ornithischian genera spanning all subclades are calculated using 2D lever arm methods. These lever arm calculations estimate the effect of jaw shape and difference in adductor muscle line of action on relative bite forces along the jaw. Results show major instances of overlap between taxa in tooth positions at which there was highest mechanical advantage. A relatively low bite force is seen across the tooth row among thyreophorans (e.g., stegosaurs and ankylosaurs), with variation among taxa. A convergent transition occurs from a more evenly distributed bite force along the jaw in basal ornithopods and basal marginocephalians to a strong distal bite force in hadrosaurids and ceratopsids, respectively. Accordingly, adductor muscle vector angles show repeated trends from a mid-range caudodorsal orientation in basal ornithischians to a decrease in vector angles indicating more caudally oriented jaw movements in derived taxa (e.g., derived thyreophorans, basal ornithopods, lambeosaurines, pachycephalosaurs, and derived ceratopsids). Analyses of hypothetical jaw morphologies were also performed, indicating that both the coronoid process and lowered jaw joint increase moment arm length therefore increasing mechanical advantage of the jaw apparatus. Adaptive trends in craniomandibular anatomy show that ornithischians evolved more complex feeding apparatuses within different clades as well as morphological convergences between clades. © 2016 Wiley Periodicals, Inc.

  16. Estimates of loss rates of jaw tags on walleyes

    USGS Publications Warehouse

    Newman, Steven P.; Hoff, Michael H.

    1998-01-01

    The rate of jaw tag loss was evaluated for walleye Stizostedion vitreum in Escanaba Lake, Wisconsin. We estimated tag loss using two recapture methods, a creel census and fykenetting. Average annual tag loss estimates were 17.5% for fish recaptured by anglers and 27.8% for fish recaptured in fyke nets. However, fyke-net data were biased by tag loss during netting. The loss rate of jaw tags increased with time and walleye length.

  17. Jaw Dislocation as an Unusual Complication of Upper Endoscopy

    PubMed Central

    Dellon, Evan S.; Steele, David

    2016-01-01

    This case report presents an unusual complication of upper endoscopy, resulting in jaw dislocation. Temporomandibular joint dislocation is commonly reported in association with anesthesia and intubation, but it is not widely recognized as a complication of gastrointestinal endoscopy. This report also reviews the current literature regarding this complication and discusses the potential causes of dislocation, differential diagnoses for jaw pain following endoscopy, and recommendations for prevention. PMID:27403117

  18. Caecilian jaw-closing mechanics: integrating two muscle systems.

    PubMed

    Kleinteich, Thomas; Haas, Alexander; Summers, Adam P

    2008-12-06

    Caecilians (Lissamphibia: Gymnophiona) are unique among vertebrates in having two sets of jaw-closing muscles, one on either side of the jaw joint. Using data from high-resolution X-ray radiation computed tomography scans, we modelled the effect of these two muscle groups (mm. levatores mandibulae and m. interhyoideus posterior) on bite force over a range of gape angles, employing a simplified lever arm mechanism that takes into account muscle cross-sectional area and fibre angle. Measurements of lever arm lengths, muscle fibre orientations and physiological cross-sectional area of cranial muscles were available from three caecilian species: Ichthyophis cf. kohtaoensis; Siphonops annulatus; and Typhlonectes natans. The maximal gape of caecilians is restricted by a critical gape angle above which the mm. levatores mandibulae will open the jaw and destabilize the mandibular joint. The presence of destabilizing forces in the caecilian jaw mechanism may be compensated for by a mandibular joint in that the fossa is wrapped around the condyle to resist dislocation. The caecilian skull is streptostylic; the quadrate-squamosal complex moves with respect to the rest of the skull. This increases the leverage of the jaw-closing muscles. We also demonstrate that the unusual jaw joint requires streptostyly because there is a dorsolateral movement of the quadrate-squamosal complex when the jaw closes. The combination of the two jaw-closing systems results in high bite forces over a wide range of gape angles, an important advantage for generalist feeders such as caecilians. The relative sizes and leverage mechanics of the two closing systems allow one to exert more force when the other has a poor mechanical advantage. This effect is seen in all three species we examined. In the aquatic T. natans, with its less well-roofed skull, there is a larger contribution of the mm. levatores mandibulae to total bite force than in the terrestrial I. cf. kohtaoensis and S. annulatus.

  19. Prototyping artificial jaws for the robotic dental testing simulator.

    PubMed

    Alemzadeh, K; Raabe, D

    2008-11-01

    This paper presents a robot periphery prototyped for the six-degrees-of-freedom robotic dental testing simulator, simulating the wear of materials on dental components, such as individual teeth, crowns, bridges, or a full set of teeth. The robot periphery consists of the artificial jaws and compliance module. The jaws have been reverse engineered and represent a human-like mandible and maxilla with artificial teeth. Each clinically fabricated tooth consists of a crown and glass ceramic roots which are connected using resin cement. Normal clinical occlusion of the artificial jaws assembly was emulated by a dental articulator based on 'Andrew's six keys to occlusion'. The radii of the von Spee curve, the Monson curve, and the Wilson curve were also measured as important jaw characteristic indicators to aid normal occlusion. A compliance module had to be built between the lower jaw and the robot platform to sustain the fluctuating forces that occur during normal chewing in the occlusal contact areas, where these high bite forces are major causes of dental component failure. A strain gauge force transducer has been integrated into the machined lower jaw, underneath the second molars, to measure axial biting forces applied to the posterior teeth. The experiments conducted have shown that the sensor is able to sense small changes in the compression force satisfactorily, when applied perpendicular to the occlusal surfaces of the teeth.

  20. Jaw movement during the speech in children with allergic rhinitis.

    PubMed

    Lima, Sandro Júnior Henrique; Pernambuco, Leandro de Araújo; Lins, Aline de Lima; Albuquerque, Lucas Carvalho Aragão; Silva, Hilton Justino da

    2015-01-01

    Allergic rhinitis can cause changes in stomatognathic functions, which may alter the mandibular dynamics. Electrognathography is used in the recording of jaw movements, making it valid for analysis of movements in speech. To characterize the amplitude and velocity of jaw movements during speech in children with and without allergic rhinitis. The sample consisted of 32 children aged 7-12 years, treated at a university hospital, divided into two groups: one with rhinitis and the other without rhinitis. To capture the jaw movements during speech, we used an electrognathography with the aid of a list of phonetically balanced figures. For the analysis of data, we used, in addition to descriptive statistics, nonparametric tests, Spearman correlation coefficient and the Mann-Whitney test, with a significant value of p=0.05. No significant difference was observed in jaw movements between groups, with values of p equals to 0.175, 0.650, and 0.462 for amplitude and jaw opening and closing velocity, respectively. However, a strong correlation was observed between the variables velocity and amplitude of mouth opening, being slightly higher in the group of children with allergic rhinitis. The amplitude and velocity of jaw movements are found to be similar in children with and without allergic rhinitis, and a correlation exits between these variables. In addition, they were more heterogeneous in the group without allergic rhinitis.

  1. Specification of jaw identity by the Hand2 transcription factor

    PubMed Central

    Funato, Noriko; Kokubo, Hiroki; Nakamura, Masataka; Yanagisawa, Hiromi; Saga, Yumiko

    2016-01-01

    Acquisition of the lower jaw (mandible) was evolutionarily important for jawed vertebrates. In humans, syndromic craniofacial malformations often accompany jaw anomalies. The basic helix-loop-helix transcription factor Hand2, which is conserved among jawed vertebrates, is expressed in the neural crest in the mandibular process but not in the maxillary process of the first branchial arch. Here, we provide evidence that Hand2 is sufficient for upper jaw (maxilla)-to-mandible transformation by regulating the expression of homeobox transcription factors in mice. Altered Hand2 expression in the neural crest transformed the maxillae into mandibles with duplicated Meckel’s cartilage, which resulted in an absence of the secondary palate. In Hand2-overexpressing mutants, non-Hox homeobox transcription factors were dysregulated. These results suggest that Hand2 regulates mandibular development through downstream genes of Hand2 and is therefore a major determinant of jaw identity. Hand2 may have influenced the evolutionary acquisition of the mandible and secondary palate. PMID:27329940

  2. A study of the emotional effects of tooth loss in an edentulous Gujarati population and its association with depression.

    PubMed

    Shah, Rupal J; Diwan, Fatema J; Diwan, Munira J; Chauhan, Vishal J; Agrawal, Hemal S; Patel, Ghanshyam C

    2015-01-01

    To fully estimate the burden of illness due to edentulism and establish valid treatment outcomes measures in this regard, it is equally important to study its psychosocial repercussions. The aim was to conduct a study to explore the emotional reactions to tooth loss, screen for current depressive symptoms and test for association between the two; among an edentulous Gujarati population. A total of 147 edentulous people visiting the Prosthodontics Department were surveyed. A questionnaire (based on previous studies) to test the emotional reactions to tooth loss and Nine Item-Patient Health Questionnaire to test for depression were used. The data were analyzed using the Chi-square (χ (2)) test with the help of SPSS v. 18.0 (IBM Corp., Armonk, NY, USA). Totally, 100 out of 147 edentulous people returned the questionnaire of which 58% experienced difficulties in accepting tooth loss and 37% felt unprepared for its effects. Those with difficulties accepting tooth loss had a greater effect on self esteem and social life, had more reservation about discussing tooth loss and was more likely to experience depression. Both groups were satisfied with dentures, had no problem meeting their friends or partners without dentures and leaving out dentures at night. About 58% of edentulous people had difficulties accepting tooth loss, which was unrelated to denture satisfaction. Respondents appeared to be restricted in social activities mainly due to functional limitations. Those with difficulties accepting tooth loss were more likely to experience depression.

  3. Impact of removable partial denture prosthesis on chewing efficiency

    PubMed Central

    BESSADET, Marion; NICOLAS, Emmanuel; SOCHAT, Marine; HENNEQUIN, Martine; VEYRUNE, Jean-Luc

    2013-01-01

    Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described. Objectives The objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters. Material and Methods Nineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded. Results With RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm. Conclusion RPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function. Clinical relevance This study encourages the clinical improvement of oral rehabilitation procedure. PMID:24212983

  4. Phosphorus Necrosis of the Jaw: A Present-day Study

    PubMed Central

    Hughes, J. P. W.; Baron, R.; Buckland, D. H.; Cooke, M. A.; Craig, J. D.; Duffield, D. P.; Grosart, A. W.; Parkes, P. W. J.; Porter, A.

    1962-01-01

    A historical note on the aetiology of phossy jaw shows that present-day knowledge is little greater than it was a century ago. The varied clinical course of the disease is described together with a report of 10 classical cases not previously reported. Six cases, not amounting to true necrosis but in which healing after dental extraction was delayed, and described, and mention is made of the noticeable differences in the oral state and appearances of tartar of healthy workmen exposed to phosphorus compared with healthy workmen not exposed. But no systematic differences of any kind were found in the incidence of general infections, fractures of bones, haematological findings, and biochemical studies of blood and urine in two groups of healthy men most exposed and least exposed to phosphorous in the same factory. An intensive study in hospital of a case of classical necrosis showed no departure from normal, except delayed healing following bone biopsy from the iliac crest, and a reversed polymorphonuclear/lymphocyte ratio. In the discussion the time of onset of necrosis after first exposure to phosphorus, clinical and radiological diagnosis, the organisms present, personal susceptibility, the appearance of the sequestra, and regeneration of bone are considered. An up-to-date note on prevention of the disease is given, although this has met with only partial success. Some persons are highly susceptible and, whilst complete protection is impossible in the light of our present knowledge, early diagnosis and modern treatment have robbed the disease of its terrible manifestations of Victorian times and turned it into a minor, although often uncomfortable complaint, with little or no resulting disability. Images PMID:14449812

  5. Flexible piezoelectric energy harvesting from jaw movements

    NASA Astrophysics Data System (ADS)

    Delnavaz, Aidin; Voix, Jérémie

    2014-10-01

    Piezoelectric fiber composites (PFC) represent an interesting subset of smart materials that can function as sensor, actuator and energy converter. Despite their excellent potential for energy harvesting, very few PFC mechanisms have been developed to capture the human body power and convert it into an electric current to power wearable electronic devices. This paper provides a proof of concept for a head-mounted device with a PFC chin strap capable of harvesting energy from jaw movements. An electromechanical model based on the bond graph method is developed to predict the power output of the energy harvesting system. The optimum resistance value of the load and the best stretch ratio in the strap are also determined. A prototype was developed and tested and its performances were compared to the analytical model predictions. The proposed piezoelectric strap mechanism can be added to all types of head-mounted devices to power small-scale electronic devices such as hearing aids, electronic hearing protectors and communication earpieces.

  6. Updates on osteonecrosis of the jaw.

    PubMed

    Yamashita, Junro; McCauley, Laurie K; Van Poznak, Catherine

    2010-09-01

    Osteonecrosis of the jaw (ONJ) is an uncommon condition noted to occur in patients with cancer who are receiving intravenous bisphosphonates. The cause of ONJ remains unknown. The leading hypotheses addressing the mechanism of ONJ are reviewed here. The present clinical data suggest that ONJ may occur in approximately 5% of patients with metastatic bone disease. The ability to predict an individual's risk of developing ONJ remains elusive. It is likely that an altered bone microenvironment and/or host defense mechanisms effected by medications used to treat patients with metastatic bone disease contributes to the development of ONJ. Medications that significantly reduce osteoclastic activity are associated with ONJ. Preclinical models of ONJ are being developed but to establish such an intricate systemic condition in animals is challenging. The ONJ field has progressed via knowledge gained by case reports, population-based studies, and emerging animal models. Still, there are myths that need to be resolved and important clues that need to be investigated. Understanding the pathophysiology of this condition will be critical to improve patient care. Communications between oncologists, dentists, basic scientists, and patients are central to effective treatment and research for this condition.

  7. Updates on Osteonecrosis of the Jaw

    PubMed Central

    Yamashita, Junro; McCauley, Laurie; Van Poznak, Catherine

    2010-01-01

    Purpose of review Osteonecrosis of the Jaw (ONJ) in an uncommon condition noted to occur in patients with cancer receiving intravenous bisphosphonates. The etiology of ONJ remains unknown. The leading hypotheses addressing the mechanism of ONJ are reviewed here. Recent findings The present clinical data suggests that ONJ may occur in approximately 5% of patients with metastatic bone disease. The ability to predict an individual’s risk of developing ONJ remains elusive. It is likely that an altered bone microenvironment and/or host defense mechanisms effected by medications used to treat patients with metastatic bone disease contributes to the development of ONJ. Medications that significantly reduce osteoclastic activity are associated with ONJ. Preclinical models of ONJ are being developed, but to establish such an intricate systemic condition in animals is challenging. Summary The ONJ field has progressed via knowledge gained by case reports, population-based studies and emerging animal models. Still, there are myths that need to be resolved and important clues that need to be investigated. Understanding the pathophysiology of this condition will be critical to improve patient care. Communications between oncologists, dentists, basic scientists and patients are central to effective treatment and research for this condition. PMID:20657284

  8. Jaw muscles of Old World squirrels.

    PubMed

    Thorington, R W; Darrow, K

    1996-11-01

    The jaw, suprahyoid, and extrinsic tongue muscles were studied in 11 genera, belonging to five tribes, of Old World squirrels. Significant variation in most of the adductor muscles is evident. The most primitive state of sciuromorphy is seen in the African tree squirrels Paraxerus and Funisciurus, especially as reflected in the anterior deep masseter. A derived state of sciuromorphy is found in five genera of Old World squirrels and perhaps evolved independently in each. Reduction of the temporalis muscle was observed in three genera, distantly related to one another. A unique arrangement of the superficial masseter is reported in the Asian giant tree squirrels, Ratufa. The arrangement of the masseter in the African pygmy squirrel, Myosciurus, is very similar to that of the South American pygmy squirrel, Sciurillus. We present hypotheses about the functional significance of these differences. In the derived state of sciuromorphy, which is found in three cases in squirrels that feed extensively on hard fruits, the anterior deep masseter is well positioned to increase the strength of the power stroke of the incisor bite. Among the pygmy squirrels, the position of the anterior deep masseter suggests that it plays a more significant role in molar chewing.

  9. [Bisphosphonates and osteonecrosis of the jaws].

    PubMed

    Urade, Masahiro

    2007-02-01

    The osteonecrosis of the jaws (ONJ) has been reported occasionally in cancer patients treated with radiotherapy and chemotherapy. However, bisphosphonate (BP)-associated ONJ in patients with cancer such as multiple myeloma, breast cancer and prostate cancer mainly administered with intravenous BPs has been first reported in 2003. Since then, many cases over 2,500 are accumulating worldwide. Since BPs are often used for osteoporosis, cancer-associated hypercalcemia and osteolytic bone metastasis, it is speculated that ONJ cases will increase in Japan where a small number of them were reported until now. Most of ONJ in cancer patients receiving BP administration occur after dental treatments such as tooth extraction, periodontal surgery and dental implants, and do not respond to conventional treatment modalities such as debridement, antibiotic therapy and hyperbaric oxygen therapy. No effective therapy for ONJ is established yet and empirical conservative therapy is recommended in the guidelines for prevention, diagnosis, and treatment of ONJ. Therefore, dentists and oral and maxillofacial surgeons need to recognize ONJ as a serious side effect of BPs and to make informed consent to the patients and a close consultation with medical oncologists for administration of BPs.

  10. Microbial signatures of oral dysbiosis, periodontitis and edentulism revealed by Gene Meter methodology.

    PubMed

    Hunter, M Colby; Pozhitkov, Alex E; Noble, Peter A

    2016-12-01

    Conceptual models suggest that certain microorganisms (e.g., the "red" complex) are indicative of a specific disease state (e.g., periodontitis); however, recent studies have questioned the validity of these models. Here, the abundances of 500+ microbial species were determined in 16 patients with clinical signs of one of the following oral conditions: periodontitis, established caries, edentulism, and oral health. Our goal was to determine if the abundances of certain microorganisms reflect dysbiosis or a specific clinical condition that could be used as a 'signature' for dental research. Microbial abundances were determined by the analysis of 138,718 calibrated probes using Gene Meter methodology. Each 16S rRNA gene was targeted by an average of 194 unique probes (n=25nt). The calibration involved diluting pooled gene target samples, hybridizing each dilution to a DNA microarray, and fitting the probe intensities to adsorption models. The fit of the model to the experimental data was used to assess individual and aggregate probe behavior; good fits (R(2)>0.90) were retained for back-calculating microbial abundances from patient samples. The abundance of a gene was determined from the median of all calibrated individual probes or from the calibrated abundance of all aggregated probes. With the exception of genes with low abundances (<2 arbitrary units), the abundances determined by the different calibrations were highly correlated (r~1.0). Seventeen genera were classified as 'signatures of dysbiosis' because they had significantly higher abundances in patients with periodontitis and edentulism when contrasted with health. Similarly, 13 genera were classified as 'signatures of periodontitis', and 14 genera were classified as 'signatures of edentulism'. The signatures could be used, individually or in combination, to assess the clinical status of a patient (e.g., evaluating treatments such as antibiotic therapies). Comparisons of the same patient samples revealed

  11. Face mask ventilation in edentulous patients: a comparison of mandibular groove and lower lip placement.

    PubMed

    Racine, Stéphane X; Solis, Audrey; Hamou, Nora Ait; Letoumelin, Philippe; Hepner, David L; Beloucif, Sadek; Baillard, Christophe

    2010-05-01

    In edentulous patients, it may be difficult to perform face mask ventilation because of inadequate seal with air leaks. Our aim was to ascertain whether the "lower lip" face mask placement, as a new face mask ventilation method, is more effective at reducing air leaks than the standard face mask placement. Forty-nine edentulous patients with inadequate seal and air leak during two-hand positive-pressure ventilation using the ventilator circle system were prospectively evaluated. In the presence of air leaks, defined as a difference of at least 33% between inspired and expired tidal volumes, the mask was placed in a lower lip position by repositioning the caudal end of the mask above the lower lip while maintaining the head in extension. The results are expressed as mean +/- SD or median (25th-75th percentiles). Patient characteristics included age (71 +/- 11 yr) and body mass index (24 +/- 4 kg/m2). By using the standard method, the median inspired and expired tidal volumes were 450 ml (400-500 ml) and 0 ml (0-50 ml), respectively, and the median air leak was 400 ml (365-485 ml). After placing the mask in the lower lip position, the median expired tidal volume increased to 400 ml (380-490), and the median air leak decreased to 10 ml (0-20 ml) (P < 0.001 vs. standard method). The lower lip face mask placement with two hands reduced the air leak by 95% (80-100%). In edentulous patients with inadequate face mask ventilation, the lower lip face mask placement with two hands markedly reduced the air leak and improved ventilation.

  12. New approach for immediate prosthetic rehabilitation of the edentulous mandible with three implants: a retrospective study.

    PubMed

    Hatano, Naoki; Yamaguchi, Masahiko; Yaita, Tomoyuki; Ishibashi, Takao; Sennerby, Lars

    2011-11-01

    Immediate/early prosthetic rehabilitation of the edentulous mandible with four or more implants for support of a fixed bridge is a well-documented procedure. Only a few studies have reported on the outcome of using three implants for this purpose. To retrospectively analyze the clinical outcome when using three implants for support of an immediately loaded fixed bridge in the totally edentulous mandible. In total, 132 patients (67 females and 65 males, mean age 62.6 years, range 35-85 years) treated with 396 implants (Brånemark System) over an 11-year period in one clinic were retrospectively analyzed with regard to implant survival. Implants with both machined and oxidized surface had been used. Eighty percent of the implants were 13 mm in length or longer. The permanent bridge with acrylic teeth was delivered to the patient the same day. The patients were re-called annually for clinical examinations. All patients had been followed for at least 1 year, with the longest follow-up of 10 years and a mean follow-up of 5 years. Thirteen implant failures in 10 patients were experienced, all occurring during the first 12 months of loading. The overall survival rate was 96.7% for implants and 92.4% for original bridges. More machined than oxidized implants failed, 7% vs. 1.2%. Fourteen additional implants were placed at the time of removal of the failed implants when also the fixed bridge was adjusted on the same day. Thus, all patients received and maintained a fixed bridge, except for a few hours in the 10 failure cases when the bridges were adjusted. This retrospective survival analysis shows that three implants can be used to support a fixed bridge for immediate loading in the edentulous mandible. The study indicated that oxidized implants were more successful than machined ones. © 2011 John Wiley & Sons A/S.

  13. Transcriptome of Healthy Gingival Tissue from Edentulous Sites in Patients with a History of Aggressive Periodontitis.

    PubMed

    Taiete, Tiago; Casarin, Renato Corrêa Viana; Silvério Ruiz, Karina Gonzales; Nociti Júnior, Francisco Humberto; Sallum, Enilson Antônio; Casati, Marcio Zaffalon

    2017-08-28

    This study evaluated the transcriptome of healthy gingival tissue from edentulous sites in patients with a history of generalized aggressive periodontitis (GAgP), chronic periodontitis (CP) and in patients with no history of periodontitis (H), using microarray and quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis. Healthy gingival tissue from edentulous sites was taken from GAgP (n =12), CP (n=12) and H (n=12) patients. Initially, total RNA from 4 tissues samples per group was employed in transcriptomic microarray analysis. Differential gene expression (fold-change), gene ontology (GO; biological process) and pathway analyses were performed. Genes that were differentially expressed and showing a significant role on altered pathways were validated by qRT-PCR analysis on 12 samples per group. In total, 270 probes sets and 50 GO groups were differentially expressed (up-regulated or down-regulated) between GAgP and H. Natural killer cell receptors and other genes related to the immune system were up-regulated in GAgP, while genes with functions in neural processes and in proliferation/differentiation of keratinocytes were under-expressed. There were 220 probe sets and 75 GO groups that were differentially expressed when comparing CP and GAgP. CP was characterized by the increased expression of genes related to responses to external stimuli and an under-expression of immune system-related genes. qRT-PCR analysis confirmed the microarray results, that KIR2DL4, IL6 and SELE were highly expressed in GAgP than CP or H patients. This study demonstrates differences in the transcriptome of healthy gingival tissue from edentulous sites from GAgP when compared with that of H or CP patients.

  14. [Prosthetic evaluation of the sagittal curve of the edentulous mandibular ridge].

    PubMed

    Fejérdy, Pál; Esztári, Imre; Kaán, Miklós

    2003-10-01

    The literature lacks reports on measurement-based investigations of the sagittal curve of the mandibular ridge. The prosthetic significance of that curve is a debated issue even today. Our investigations have been carried out on functional samples of randomly selected edentulous patients (55 females and 17 males) treated at the Department of Prosthodontics of the Semmelweis University, Budapest. We made photographs using a Polaroid MACRO 5 SLR camera on a squared factory-made film, under standard circumstances, from both right and left directions. The photographs were then scanned with 600 dpi resolution and saved as non-compressed tif files (Tag Image File Format). The evaluation of the digitalized photographs has been carried out using a specifically developed computer program. On the four-times enlarged pictures, we made three measurements at each point; the arithmetical means of those sets of three figures served as a basis for statistical analysis. The data were analysed by gender and by side, using the SPSS program package (t-test). Our measurements showed that the sagittal curve is characteristic of the edentulous mandibular ridge as well. However, it does not exhibit significant differences by gender, individual, or side. The average value of the lowest point of the sagittal curve was 5.78 mm, s +/- 1.96 mm, minimum = 1.83 mm, maximum = 11.12 mm. It was concluded from our measurements and comparative anatomical data--clinical observations, as well as measurement-based investigations--that the Spee-curve of the healthy dentition and the sagittal curve of the edentulous mandibular ridge are formed by the same forces. If, in everyday practice, sagittal curves of the occlusion surfaces of complete lower dentures are set parallel with the mandibular edge, this is the most preferable solution with respect to both the stability of complete lower dentures and the optimal functioning of constrictor muscles.

  15. Severe edentulism is a major risk factor influencing stroke incidence in rural Ecuador (The Atahualpa Project).

    PubMed

    Del Brutto, Oscar H; Mera, Robertino M; Zambrano, Mauricio; Del Brutto, Victor J

    2017-02-01

    Background There is no information on stroke incidence in rural areas of Latin America, where living conditions and cardiovascular risk factors are different from urban centers. Aim Using a population-based prospective cohort study design, we aimed to assess risk factors influencing stroke incidence in community-dwelling adults living in rural Ecuador. Methods First-ever strokes occurring from 1 June 2012 to 31 May 2016, in Atahualpa residents aged ≥40 years, were identified from yearly door-to-door surveys and other overlapping sources. Poisson regression models adjusted for demographics, cardiovascular risk factors, edentulism and the length of observation time per subject were used to estimate stroke incidence rate ratio as well as factors influencing such incidence. Results Of 807 stroke-free individuals prospectively enrolled in the Atahualpa Project, follow-up was achieved in 718 (89%), contributing 2,499 years of follow-up (average 3.48 ± 0.95 years). Overall stroke incidence rate was 2.97 per 100 person-years of follow-up (95% CI: 1.73-4.2), which increased to 4.77 (95% CI: 1.61-14.1) when only persons aged ≥57 years were considered. Poisson regression models, adjusted for relevant confounders, showed that high blood pressure (IRR: 5.24; 95% CI: 2.55-7.93) and severe edentulism (IRR: 5.06; 95% CI: 2.28-7.85) were the factors independently increasing stroke incidence. Conclusions Stroke incidence in this rural setting is comparable to that reported from the developed world. Besides age and high blood pressure, severe edentulism is a major factor independently predicting incident strokes. Public awareness of the consequences of poor dental care might reduce stroke incidence in rural settings.

  16. A Novel Technique for Attaining Maxillomandibular Fixation in the Edentulous Mandible Fracture

    PubMed Central

    Knotts, Christopher; Workman, Meredith; Sawan, Kamal; El Amm, Christian

    2012-01-01

    Edentulous mandible fractures present a unique and challenging surgical problem, particularly because of lack of occlusive dental surfaces to capitalize upon maxillomandibular fixation (MMF). We present a novel technique to achieve MMF using rigid plates spanning the oral cavity to fixate the maxilla to the mandible. The process is rapid and allows stability using the established principles of rigidity, external fixation, and osteosynthesis. This technique allows for a faster MMF than with a Gunning splint and allows for easier oral hygiene. An illustrative case and pre- and postoperative imaging are provided. PMID:23449752

  17. A novel technique for attaining maxillomandibular fixation in the edentulous mandible fracture.

    PubMed

    Knotts, Christopher; Workman, Meredith; Sawan, Kamal; El Amm, Christian

    2012-03-01

    Edentulous mandible fractures present a unique and challenging surgical problem, particularly because of lack of occlusive dental surfaces to capitalize upon maxillomandibular fixation (MMF). We present a novel technique to achieve MMF using rigid plates spanning the oral cavity to fixate the maxilla to the mandible. The process is rapid and allows stability using the established principles of rigidity, external fixation, and osteosynthesis. This technique allows for a faster MMF than with a Gunning splint and allows for easier oral hygiene. An illustrative case and pre- and postoperative imaging are provided.

  18. Prosthodontic rehabilitation after myofascial flap surgery of hemimaxillectomy defects in the edentulous patient: a clinical report.

    PubMed

    Lee, Joon-Seok; Lim, Young-Jun

    2014-01-01

    The aims of this clinical report were to present and discuss the clinical procedure and the treatment considerations of prosthetic rehabilitation after myofascial flap surgery. A 78-year-old edentulous woman with a squamous cell carcinoma underwent hemimaxillectomy. A temporalis myofascial flap surgery combined with implant-supported prosthesis is one successful approach to the restoration of oral function after hemimaxillectomy. Although the bulky and mobile nature of a temporalis myofascial flap prevented the retention of a tissue-borne denture, an appropriate impression technique and the fabrication of implant-supported prosthesis using an implant attachment system enhanced the overall satisfaction by the patient.

  19. Lack of association between oral bisphosphonates and osteonecrosis using jaw surgery as a surrogate marker.

    PubMed

    Pazianas, M; Blumentals, W A; Miller, P D

    2008-06-01

    Using jaw surgery as a surrogate marker for osteonecrosis of the jaw, this exploratory study did not find that the risk of jaw surgery was significantly increased with the use of oral bisphosphonates in postmenopausal women. The objective of this analysis was to explore the potential association between jaw surgery (as a surrogate marker for osteonecrosis of the jaw) and the use of oral bisphosphonates in postmenopausal women. A claims database was used to identify female patients > or = 45 years of age with jaw surgery claims from January 1, 2002 to December 31, 2005. Four controls (patients with no claims for jaw surgery) were matched to each jaw surgery case. Additional patient data collected included oral bisphosphonate prescriptions (including alendronate, risedronate, or ibandronate) and comorbid conditions. A total of 697 jaw surgery cases and 2,808 controls were identified. Of those jaw surgery cases, 96 (13.8%) received at least one prescription for an oral bisphosphonate. After adjustment for confounding variables, receiving at least one oral bisphosphonate prescription was not shown to significantly increase the risk of jaw surgery (odds ratio(adjusted) = 0.91; 95% confidence interval = 0.70-1.19). When bisphosphonate use was stratified by duration on therapy, no significant increases in the risk of jaw surgery were observed in any group. This exploratory analysis did not find a significant association between oral bisphosphonate use and increased risk of jaw surgery, a surrogate marker for osteonecrosis of the jaw.

  20. Factors associated with osteonecrosis of the jaw among bisphosponate users

    PubMed Central

    Hess, Lisa M; Jeter, Joanne M; Benham-Hutchins, Marge; Alberts, David S.

    2008-01-01

    Background Bisphosphonates are medications that impact bone reformation by inhibiting osteoclast function. Osteonecrosis of the jaw has been reported among patients receiving these medications. It is unclear if the risk factors associated with osteonecrosis of the jaw among cancer patients taking bisphosphonates are also possible risk factors among patients receiving these medications for other indications. Methods A systematic review search strategy was used to identify cases of osteonecrosis of the jaw among patients taking bisphosphonates for an indication other than cancer to identify potential contributing factors. Data were analyzed according to previous models to develop a more expanded model that may explain possible mechanisms for the development of osteonecrosis of the jaw among patients without cancer. Results Ninety-nine cases of osteonecrosis of the jaw were identified among patients who were prescribed a bisphosphonate for an indication other than cancer. These cases included 85 osteoporosis patients, 10 patients with Paget’s disease, two patients with rheumatoid arthritis, one patient with diabetes and one patient with maxillary fibrous dysplasia. The mean age was 69.4 years, 87.3% were female, and 87.6% were receiving oral, but not intravenous, bisphosphonates. Of the 63 patients reporting dental care information, 88.9% had a dental procedure prior to the onset of osteonecrosis of the jaw. Of all cases providing medical information, 71% were taking at least one medication that affects bone turnover in addition to the bisphosphonate, and 81.6% reported additional underlying health conditions. Conclusions The case details suggest a multiplicity of factors associated with this condition and provide the foundation for a model outlining the potential mechanism for the development of osteonecrosis of the jaw among patients taking bisphosphonates for an indication other than cancer. PMID:18501224

  1. Surgical treatment of jaw osteonecrosis in "Krokodil" drug addicted patients.

    PubMed

    Poghosyan, Yuri M; Hakobyan, Koryun A; Poghosyan, Anna Yu; Avetisyan, Eduard K

    2014-12-01

    Retrospective study of jaw osteonecrosis treatment in patients using the "Krokodil" drug from 2009 to 2013. On the territory of the former USSR countries there is widespread use of a self-produced drug called "Krokodil". Codeine containing analgesics ("Sedalgin", "Pentalgin" etc), red phosphorus (from match boxes) and other easily acquired chemical components are used for synthesis of this drug, which used intravenously. Jaw osteonecrosis develops as a complication in patients who use "Krokodil". The main feature of this disease is jawbone exposure in the oral cavity. Surgery is the main method for the treatment of jaw osteonecrosis in patients using "Krokodil". 40 "Krokodil" drug addict patients with jaw osteonecrosis were treated. Involvement of maxilla was found in 11 patients (27.5%), mandible in 21 (52.5%), both jaws in 8 (20%) patients. 35 Lesions were found in 29 mandibles and 21 lesions in 19 maxillas. Main factors of treatment success are: cessation of "Krokodil" use in the pre- (minimum 1 month) and postoperative period and osteonecrosis area resection of a minimum of 0.5 cm beyond the visible borders of osteonecrosis towards the healthy tissues. Surgery was not delayed until sequestrum formation. In the mandible marginal or segmental resection (with or without TMJ exarticulation) was performed. After surgery recurrence of disease was seen in 8 (23%) cases in the mandible, with no cases of recurrence in the maxilla. According to our experience in this case series, surgery is the main method for the treatment of jaw osteonecrosis in patients using "Krokodil". Cessation of drug use and jaw resection minimize the rate of recurrences in such patients.

  2. Segmental sandwich osteotomy and tunnel technique for three-dimensional reconstruction of the jaw atrophy: a case report.

    PubMed

    Santagata, Mario; Sgaramella, Nicola; Ferrieri, Ivo; Corvo, Giovanni; Tartaro, Gianpaolo; D'Amato, Salvatore

    2017-12-01

    A three-dimensionally favourable mandibular bone crest is desirable to be able to successfully implant placement to meet the aesthetic and functional criteria in the implant-prosthetic rehabilitation. Several surgical procedures have been advocated for bone augmentation of the atrophic mandible, and the sandwich osteotomy is one of these techniques. The aim of the present case report was to assess the suitability of segmental mandibular sandwich osteotomy combined with a tunnel technique of soft tissue. Based on our knowledge, nobody described before the sandwich osteotomy with tunnel technique to improve the healing of the wound and meet the dimensional requirements of preimplant bone augmentation in cases of a severely atrophic mandible. A 59-year-old woman with a severely atrophied right mandible was treated with the sandwich osteotomy technique filled with autologous bone graft harvested by a cortical bone collector from the ramus. Clinical examination revealed that the mandible was edentulous bilaterally from the first molar to the second molar region. Radiographically, atrophy of the mandibular alveolar ridge in the same teeth site was observed. We began to treat the right side. A horizontal osteotomy of the edentulous mandibular bone was then made with a piezoelectric device after tunnel technique of the soft tissue. The segmental mandibular sandwich osteotomy (SMSO) was finished by two (mesial and distal) slightly divergent vertical osteotomies. The entire bone fragment was displaced cranially, and the desirable position was obtained. The gap was filled completely with autologous bone chips harvested from the mandibular ramus through a cortical bone collector. No barrier membranes were used to protect the grafts. The vertical incisions were closing with interruptive suturing of the flaps with a resorbable material. In this way, the suture will not fall on the osteotomy line of the jaw; the result will be a better predictability of soft and hard tissue

  3. Osteonecrosis of the Jaw Developed in Mice

    PubMed Central

    Park, Sil; Kanayama, Keiichi; Kaur, Kawaljit; Tseng, Han-Ching Helen; Banankhah, Sina; Quje, Davood Talebi; Sayre, James W.; Jewett, Anahid; Nishimura, Ichiro

    2015-01-01

    Osteonecrosis of the jaw (ONJ), an uncommon co-morbidity in patients treated with bisphosphonates (BP), occurs in the segment of jawbone interfacing oral mucosa. This study aimed to investigate a role of oral mucosal barrier γδ T cells in the pathogenesis of ONJ. Female C57Bl/6J (B6) mice received a bolus zoledronate intravenous injection (ZOL, 540 μg/kg), and their maxillary left first molars were extracted 1 week later. ZOL-treated mice (WT ZOL) delayed oral wound healing with patent open wounds 4 weeks after tooth extraction with characteristic oral epithelial hyperplasia. γδ T cells appeared within the tooth extraction site and hyperplastic epithelium in WT ZOL mice. In ZOL-treated γδ T cell null (Tcrd−/− ZOL) mice, the tooth extraction open wound progressively closed; however, histological ONJ-like lesions were identified in 75 and 60% of WT ZOL and Tcrd−/− ZOL mice, respectively. Although the bone exposure phenotype of ONJ was predominantly observed in WT ZOL mice, Tcrd−/− ZOL mice developed the pustule/fistula disease phenotype. We further addressed the role of γδ T cells from human peripheral blood (h-γδ T cells). When co-cultured with ZOL-pretreated human osteoclasts in vitro, h-γδ T cells exhibited rapid expansion and robust IFN-γ secretion. When h-γδ T cells were injected into ZOL-treated immunodeficient (Rag2−/− ZOL) mice, the oral epithelial hyperplasia developed. However, Rag2−/− ZOL mice did not develop osteonecrosis. The results indicate that γδ T cells are unlikely to influence the core osteonecrosis mechanism; however, they may serve as a critical modifier contributing to the different oral mucosal disease variations of ONJ. PMID:26013832

  4. Risk Factors for Osteonecrosis of the Jaws

    PubMed Central

    Barasch, A.; Cunha-Cruz, J.; Curro, F.A.; Hujoel, P.; Sung, A.H.; Vena, D.; Voinea-Griffin, A.E.; Beadnell, Steven; Craig, Ronald G.; DeRouen, Timothy; Desaranayake, Ananda; Gilbert, Ann; Gilbert, Gregg H.; Goldberg, Ken; Hauley, Richard; Hashimoto, Mariko; Holmes, Jon; Latzke, Brooke; Leroux, Brian; Lindblad, Anne; Richman, Joshua; Safford, Monika; Ship [deceased], Jonathan; Thompson, Van P.; Williams, O. Dale; Yin, Wanrong

    2011-01-01

    Case reports and cohort studies have linked bisphosphonate therapy and osteonecrosis of the jaws (ONJ), but neither causality nor specific risks for lesion development have been clearly established. We conducted a 1:3 case-control study with three dental Practice-based Research Networks, using dentist questionnaires and patient interviews for collection of data on bisphosphonate therapy, demographics, co-morbidities, and dental and medical treatments. Multivariable logistic regression analyses tested associations between bisphosphonate use and other risk factors with ONJ. We enrolled 191 ONJ cases and 573 controls in 119 dental practices. Bisphosphonate use was strongly associated with ONJ (odds ratios [OR] 299.5 {95%CI 70.0-1282.7} for intravenous [IV] use and OR = 12.2 {4.3-35.0} for oral use). Risk markers included local suppuration (OR = 7.8 {1.8-34.1}), dental extraction (OR = 7.6 {2.4-24.7}), and radiation therapy (OR = 24.1 {4.9-118.4}). When cancer patients (n = 143) were excluded, bisphosphonate use (OR = 7.2 {2.1-24.7}), suppuration (OR = 11.9 {2.0-69.5}), and extractions (OR = 6.6 {1.6-26.6}) remained associated with ONJ. Higher risk of ONJ began within 2 years of bisphosphonate initiation and increased four-fold after 2 years. Both IV and oral bisphosphonate use were strongly associated with ONJ. Duration of treatment > 2 years; suppuration and dental extractions were independent risk factors for ONJ. PMID:21317246

  5. Full arch restoration with computer-assisted implant surgery and immediate loading in edentulous ridges with dental fresh extraction sockets. One year results of 10 consecutively treated patients: guided implant surgery and extraction sockets.

    PubMed

    Meloni, Silvio Mario; De Riu, Giacomo; Pisano, Milena; Tullio, Antonio

    2013-09-01

    There is a growing need for patients to be rehabilitated with a fixed, implant-supported prosthesis immediately after surgery. The present study aims to describe the results of a modified prosthetic and surgical protocol of computer-assisted implant insertion and immediate loading in edentulous jaws with extraction sockets. Ten patients were consecutively treated with a modified computer assisted implant surgery protocol and screw-retained provisional metal-acrylic prosthesis prepared ahead of surgery and delivered immediately. Overall, 60 implants (Nobel Replace Tapered Groovy) were inserted, of which 22 were inserted in fresh extraction sockets. Definitive prosthesis was delivered after 6-12 months. Outcome measures were radiographic marginal bone-level changes, survival of implants, and patient satisfaction. The follow-up period was of at least 12 months. All the patients felt comfortable and none withdrew from the study. No implants were lost, resulting in a cumulative survival rate of 100 %. Radiological estimation showed a mean peri-implant marginal bone loss of 1.4 ± 0.3 mm. No other complications, biological or mechanical, were recorded. In all cases, patients appeared to be very satisfied with the aesthetic and function. Within the limitations of this study, our data seem to validate this surgical and prosthetic protocol with valid functional and aesthetic results when applied in selected cases.

  6. Three-dimensional distortion of gold alloy castings and welded titanium frameworks. Measurements of the precision of fit between completed implant prostheses and the master casts in routine edentulous situations.

    PubMed

    Jemt, T

    1995-08-01

    Thirty routine patients, provided with fixed prostheses supported by osseointegrated Brånemark implants in edentulous lower jaws, were arranged into three different groups with regard to design of the metal framework. Ten patients received cast gold alloy frames and the other two groups were provided with two different designs of welded titanium frames. The fit of the completed prostheses was measured in three dimensions (3-D) in relation to the master cast, by means of a photogrammetric technique, prior to insertion. Mean 3-D distortion of the centre point of the gold cylinder was 42 (s.d. 8) microns for the cast framework. The corresponding mean distortion for the two designs of titanium frameworks was 43 (s.d. 16) and 36 (s.d. 10) microns, respectively. Least distortion was observed in vertical direction for all three designs. None of the different designs of metal frames showed a significantly better fit (P > 0.05), but the cast and oldest titanium framework design presented a much wider range of distortion. This indicated a higher risk of sectioning and resoldering during the fabrication of the prostheses as compared to the more consistently fabricated prostheses, with a new titanium framework design.

  7. Retrospective success and survival rates of dental implants placed with simultaneous bone augmentation in partially edentulous patients.

    PubMed

    Bazrafshan, Nima; Darby, Ivan

    2014-07-01

    The aim of this study was to assess the success and survival rate of dental implants placed with simultaneous hard tissue grafting. All patients treated in Royal Dental Hospital of Melbourne who had implant placement with and without guided bone regeneration (GBR) procedures were identified. Seventy-three attended a follow-up appointment. These patients were examined recording probing depth, bleeding on probing, plaque accumulation and radiographic bone loss by one examiner. Clinical and radiographic findings were compared in grafted and non-grafted groups and also analysed for years in function. Approximately 50% of implants were placed simultaneous guided bone regeneration technique. In the majority of cases, defects were filled by deproteinized bovine bone mineral and covered with collagen membrane. The range of time in function was 20-88 months with a mean 34.8 (±1.7). Seventy-nine per cent of the implants placed in anterior maxilla were placed with GBR, while only 18% in posterior mandible needed grafting procedure. The cumulative implant survival rates at the time of examination was 97.95% for both GBR and non-GBR group. The mean PPD, BOP, and Plaque index were not statistically significantly different in GBR vs. non-GBR groups two to seven years in function. However, bone loss is significantly less in GBR group 2-7 years after function. The overall success rate was around 90% after 2-7 years in function with the GBR group slightly less than the non-GBR group, but not statistically significant. For the subjects included in this retrospective study, the data demonstrate that GBR is a predictable procedure. The survival and success rates of the implants inserted with simultaneous GBR were similar, if slightly lower, to the non-grafted implants. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Astra Tech, Brånemark, and ITI implants in the rehabilitation of partial edentulism: two-year results.

    PubMed

    Bilhan, Hakan; Kutay, Omer; Arat, Selda; Cekici, Ali; Cehreli, Murat Cavit

    2010-10-01

    To explore the soft tissue, marginal bone, and prosthetic complications (if any) of Astra Tech, Brånemark, and ITI implants supporting fixed prostheses during an observation period of 2 years. The study comprised 26 patients, who received 42 Astra Tech, 36 Brånemark, and 29 ITI implants. After 3 months of healing, abutment connections were performed for Astra Tech and Brånemark implants, and fixed prostheses were delivered to the patients at 4 months. At 6-month, 1-year, and 2-year recall appointments, plaque index, periimplant inflammation index, and bleeding index scores, were recorded. The marginal bone levels were also measured at 2-year recall by means of radiographic evaluation, and prosthetic complications were recorded throughout the study. All implants survived during the 2-year observation period. The plaque index and periimplant inflammation index scores around Brånemark implants were higher than ITI and Astra Tech implants in the first year of function (P > 0.05). Marginal bone loss around ITI and Astra Tech implants was similar at 2 years (P > 0.05). The marginal bone loss around Brånemark implants was higher than Astra Tech implants (P < 0.05) but similar to ITI implants at 2-year recall appointment (P > 0.05). Fixed prostheses supported by ITI and Astra Tech implants did not experience prosthetic complications, and only 1 patient of the Brånemark group had porcelain veneer fracture. Astra Tech, Brånemark, and ITI implants supporting fixed prostheses had same survival rates (100%) in this study. ITI and Astra Tech implants had similar changes in marginal bone levels, whereas Brånemark implants had higher marginal bone loss, particularly in the first year of function.

  9. [New protocol combining orthodontics and implant therapy for partially edentulous adult patients. Part I: Description of the Decker protocol].

    PubMed

    Davarpanah, K; Decker, A; Sache, M P; Deffrennes, D; Demurashvili, G; Szmukler-Moncler, S

    2014-12-01

    The treatment of adult malocclusion is usually complex and pluridisciplinary. Its prognosis is not reliable. We present a new clinical protocol to improve the management and final result. We use a specific software (Simplant®, OMS®, Materialise Dental) and its accessory modules. It allows visualization of the expected final clinical result of the orthodontic treatment. Combined with guided-surgery, it allows placing implants at the beginning of treatment in a position that is compatible with the final position. The implants serve as absolute anchorage for dental motions during the orthodontic step; it is also used to support the final prosthesis. The treatment is thus optimized and its prognosis is improved. Finally, the reversed surgical sequences shorten the treatment thus promoting the compliance of patients. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Palatal Rugae Patterns in Edentulous Cases, Are They A Reliable Forensic Marker?

    PubMed Central

    Poojya, R.; Shruthi, C. S.; Rajashekar, Vaishali Mysore; Kaimal, Aswathy

    2015-01-01

    One of the main objectives of the forensic sciences is establishing a person’s identity which can be a very complex process. The analysis of the teeth, fingerprints and DNA evaluation are probably the most used techniques allowing fast and secure identification processes. Palatal rugae or transverse palatine folds are asymmetrical and irregular elevations of the mucosa located in the anterior third of the palate and are permanent, prominent and unique for individuals and thus can be used as identification for forensic purposes widely in edentulous patients wherein no teeth are present in the oral cavity. In forensic odontology dentists play a prime role in supporting legal and criminal issues. Palatoscopy or palatal rugoscopy is the name given to the study of palatal rugae in order to ascertain a person’s identity. Studies have demonstrated that no two individual rugae patterns are alike in their configuration and the characteristic rugae pattern of the palate does not change as a result of growth. Hence this article reviews the significance of palatal rugae patterns in edentulous cases as a reliable forensic marker. PMID:26508904

  11. Palatal Rugae Patterns in Edentulous Cases, Are They A Reliable Forensic Marker?

    PubMed

    Poojya, R; Shruthi, C S; Rajashekar, Vaishali Mysore; Kaimal, Aswathy

    2015-09-01

    One of the main objectives of the forensic sciences is establishing a person's identity which can be a very complex process. The analysis of the teeth, fingerprints and DNA evaluation are probably the most used techniques allowing fast and secure identification processes. Palatal rugae or transverse palatine folds are asymmetrical and irregular elevations of the mucosa located in the anterior third of the palate and are permanent, prominent and unique for individuals and thus can be used as identification for forensic purposes widely in edentulous patients wherein no teeth are present in the oral cavity. In forensic odontology dentists play a prime role in supporting legal and criminal issues. Palatoscopy or palatal rugoscopy is the name given to the study of palatal rugae in order to ascertain a person's identity. Studies have demonstrated that no two individual rugae patterns are alike in their configuration and the characteristic rugae pattern of the palate does not change as a result of growth. Hence this article reviews the significance of palatal rugae patterns in edentulous cases as a reliable forensic marker.

  12. Oral health-related quality of life of edentulous patients after complete dentures relining.

    PubMed

    Krunić, Nebojsa; Kostić, Milena; Petrović, Milica; Igić, Marko

    2015-04-01

    Tooth loss affects oral health-related life quality. More than a third of edentulous patients are not fully satisfied with their complete dentures and mainly complain of insufficient stability, retention, and pain during mastication. Solving the problem may include relining by materials that are based on silicone or acrylic. The aim of this study was to determine the level of patients' satisfaction before and after relining upper dentures with soft and rigid liners. The patients (n=24) were divided into two study groups. Maxillary denture relining of the first group of patients was performed with hard acrylic based resins while in the second group of patients complete denture was relined with a silicone-based soft liner. They were asked the questions from the specifically adapted the Oral Health Impact Profile Questionnaire for edentulous patients before and three months after relining dentures. After relining the patients showed a higher degree of satisfaction with their dentures in all the tested domains (masticatory function, psychological discomfort, social disability and retention and hygiene). The padents with soft denture relines were more satisfied. Refining of maxillary complete dentures significantly positively impacts the quality of life of patients in all the tested domains (masticatory function, psychological discomfort, social disability, pain and oral hygiene). Better results were achieved using a silicone-based soft liner, which recommends it as the material of choice for relining dentures.

  13. Prevalence of caries and edentulousness among 65-74-year-olds in Europe.

    PubMed Central

    Bourgeois, D.; Nihtila, A.; Mersel, A.

    1998-01-01

    Reviewed in this article are epidemiological studies included in the WHO Global Oral Data Bank for noninstitutionalized European adults aged 65-74 years for the period 1986-96. Edentulous percentages, decayed, missing, filled teeth (DMFT) index, and data on the mean number of teeth are presented. At least one representative study had been carried out in 48% of the countries, with the quantity of information from countries with developed market economies being similar to that from countries with economies in transition. The proportion of 65-74-year-olds who were edentulous varied from 12.8% to 69.6%, the mean number of teeth ranged from 15.1 to 3.8, and the DMFT index from 22.2 to 30.2. The observed disparities in the oral health status among older European adults suggest that it may be possible to develop and implement oral health policies that take into account geographical and socioeconomic differences in populations. PMID:9803592

  14. Treatment of edentulism: optimizing outcomes with tissue management and impression techniques.

    PubMed

    Salinas, Thomas J

    2009-02-01

    Significant numbers of patients throughout the world seek treatment for edentulism. The trend toward tissue-integrated prostheses has been a monumental step in restoring edentulous patients to function; however, this treatment can be out of reach for those who fail to qualify or those who do not have sufficient resources to afford it. In these cases, conventional dentures remain an important primary course of treatment. Attention to detail when diagnosing, treatment planning, and performing treatment for these patients is still a prime consideration for the best possible outcome. In particular, many experienced denture wearers are afflicted with chronically inflamed denture-bearing mucosa. Clinicians must recognize the need for tissue conditioning, choices of impression materials, and accepted fabrication techniques that can have favorable outcomes when matched with patients who are philosophical and realistic in their expectations. The purpose of this article is to review impression philosophies, associated materials, and methods of tissue conditioning. Retention and stability of the denture bases can be augmented by the routine use of denture adhesive, and indications for use of denture adhesive will be discussed.

  15. Nitric Oxide Concentration and Other Salivary Changes after Insertion of New Complete Dentures in Edentulous Subjects

    PubMed Central

    Breseghelo, Maria de Lourdes; Guillo, Lídia Andreu; Nogueira, Túlio Eduardo

    2016-01-01

    Objective. To assess changes in levels of salivary nitric oxide (NO) after insertion of new complete dentures and its association with clinical and salivary parameters. Methods. Nineteen fully edentulous subjects were included, mean age 64.4. Unstimulated whole saliva was collected before and after insertion of the dentures, at follow-up visits, and after 12 months. The concentration of the final stable NO product (nitrite) was measured by a colorimetric assay based on the Griess reaction. Clinical parameters were assessed during all clinical visits. Results. Functional adaptation to the dentures progressively improved, with no complaints at the long-term follow-up. NO concentration was not influenced by the level of functional adaptation, presence of injuries to the mucosa, salivary flow, and saliva viscosity. Pairwise comparison showed a reduction in NO concentration at the first follow-up compared to baseline values but differences were not statistically significant. Significant differences were observed in NO concentrations at the long-term follow-up when compared to the first (p = 0.024) and second (p = 0.027) visits. Conclusion. NO concentration reduced after denture insertion and returned to baseline levels in the long-term follow-up. This appears to be an autonomic response of the body and provides valuable complementary information for the management of the edentulous patient. PMID:27034674

  16. Prosthetic rehabilitation of edentulous ridges following alveolar distraction osteogenesis: clinical report of three cases.

    PubMed

    Ergun, Gulfem; Nagas, Isil Cekic; Yilmaz, Dervis; Ozturk, Mustafa

    2011-03-01

    Patients with complete edentulism who have insufficient bone for endosseous dental implant treatment present a challenge for dental practitioners. Distraction osteogenesis of the edentulous alveolar ridges is a process for augmentation of atrophic alveolar bone before dental implant placement. This clinical report describes the use of distraction osteogenesis and rehabilitation of patients with a fixed or removable implant-supported prosthesis to treat mandibular defects. Two female patients with segmental alveolar atrophy at the posterior regions of mandible and one female patient with defect at the anterior region of mandible were treated using distraction devices. However, lingual tipping of the distraction vector occurred during the distraction phase in patient 1. The morphology of the alveolar bone was also analyzed in relation to the planned implant position. After a consolidation period of 12 weeks on average, radiologic observation suggested that there was sufficient bone formation for implant installation. In all patients, implant-supported fixed or removable prosthetic oral rehabilitation was successfully performed, and the clinical and radiologic findings were satisfactory. After 4 years of follow-up, no functional or esthetic difficulties with the implants and restorations were noted. These case reports suggest that although alveolar distraction osteogenesis seems to be an effective technique for augmenting atrophic alveolar bone for creating bone and soft tissue, complications may occur after surgical procedures.

  17. Registration for computer-navigated surgery in edentulous patients: a problem-based decision concept.

    PubMed

    Lübbers, Heinz-Theo; Matthews, Felix; Zemann, Wolfgang; Grätz, Klaus W; Obwegeser, Joachim A; Bredell, Marius

    2011-09-01

    Surgical navigation is a commonly used tool in cranio-maxillofacial surgery. Registration is the key element for precision, and a number of studies have shown different techniques to be accurate. Nonetheless, uncertainty surrounds the special situation in edentulous patients and a practical approach to what can be a challenging problem. Four registration strategies for the Brainlab VectorVision(2) system are presented for surgical navigation of edentulous patients: three landmark-based, point-to-point techniques and one surface-based matching strategy are evaluated. The methods described differ in overall accuracy as well as in the region covered. In general, the more time-consuming and invasive the technique, the more precise it is. The non-invasive techniques are less precise, and they cover only small regions with sufficient accuracy. Taking into account which type of accuracy is clinically relevant and that the whole skull does not always need to be covered with the greatest possible accuracy, all the described techniques have their indications. The simpler and less invasive techniques can spare time, decrease costs, and harm patient. A decision tree is presented to the reader. Copyright © 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  18. Rehabilitation with implant-supported overdentures in total edentulous patients: A review.

    PubMed

    Martínez-Lage-Azorín, Juan F; Segura-Andrés, Gustavo; Faus-López, Joan; Agustín-Panadero, Rubén

    2013-12-01

    The main aim of this review article is to discuss implant-supported overdentures (ISOs) as treatment in edentulous patients. Besides, we will try to discuss among the different treatment options in such patients and to analyze their validity when ISOs are compared with other clinical modalities. At the same time, we will try to suggest clinical guidelines supported by current clinical studies. We performed a Medline search and review of pertinent articles on the mentioned subject from 1986 to 2011. As a searching strategy, we used the following words: implant-supported overdentures, attachment systems, Locator attachment, cantilever, fixed prosthesis. Implant-supported overdentures constitute an accurate and predictable treatment option and achieve a higher patients' satisfaction. This type of treatment constitutes a cheaper treatment than fixed prostheses and in some patients, with loss of lip support or with an interoclusal space larger than 15 mm, the choice of implant-supported overdentures seems to prevent future aesthetic or phonetic problems. Key words:Overdentures, implant occlusion, implant rehabilitation, total edentulous rehabilitation, fixed prosthesis.

  19. Transpositioned flap vestibuloplasty combined with implant surgery in the severely resorbed atrophic edentulous ridge.

    PubMed

    Kao, Shou-Yen; Yeung, Tze-Cheung; Hung, Kai-Feng; Chou, I-Chiang; Wu, Che-Hsian; Chang, Richard Che-Shoa

    2002-01-01

    The use of transpositioned flap (lipswitch) vestibuloplasty combined with implant surgery in patients with severely resorbed atrophic edentulous ridges is reviewed. The cases of 17 patients with severely resorbed atrophic edentulous ridges at the mandible undergoing implant rehabilitation were reviewed. Lipswitch vestibuloplasty was followed immediately by the implant surgery. Postoperative follow-up consisted of clinical and radiographic examinations. Seventeen patients with atrophic ridges (12 class II and 5 class III) each had 2 implant fixtures placed in the mandible as abutments for a clip and bar overdenture. The average time of follow-up was 6 years. Before surgery, all patients had severely atrophic ridges with a compromised shallow vestibule of varying degrees. Satisfactory results were observed in regard to the immediate and long-term morphology of the vestibule, the health of the peri-implant tissue, the stability of implant fixtures, and the functionality of the prostheses. The lipswitch vestibuloplasty offers a safe and convenient method of surgical access for implant fixture installation, with the advantage of rebuilding the vestibule of a compromised atrophic ridge in the anterior mandible.

  20. Rehabilitation with implant-supported overdentures in total edentulous patients: A review

    PubMed Central

    Segura-Andrés, Gustavo; Faus-López, Joan; Agustín-Panadero, Rubén

    2013-01-01

    Objectives: The main aim of this review article is to discuss implant-supported overdentures (ISOs) as treatment in edentulous patients. Besides, we will try to discuss among the different treatment options in such patients and to analyze their validity when ISOs are compared with other clinical modalities. At the same time, we will try to suggest clinical guidelines supported by current clinical studies. Material and methods: We performed a Medline search and review of pertinent articles on the mentioned subject from 1986 to 2011. As a searching strategy, we used the following words: implant-supported overdentures, attachment systems, Locator attachment, cantilever, fixed prosthesis. Results and conclusions: Implant-supported overdentures constitute an accurate and predictable treatment option and achieve a higher patients’ satisfaction. This type of treatment constitutes a cheaper treatment than fixed prostheses and in some patients, with loss of lip support or with an interoclusal space larger than 15 mm, the choice of implant-supported overdentures seems to prevent future aesthetic or phonetic problems. Key words:Overdentures, implant occlusion, implant rehabilitation, total edentulous rehabilitation, fixed prosthesis. PMID:24455093

  1. Neural crest cell-derived VEGF promotes embryonic jaw extension

    PubMed Central

    Wiszniak, Sophie; Mackenzie, Francesca E.; Anderson, Peter; Kabbara, Samuela; Ruhrberg, Christiana; Schwarz, Quenten

    2015-01-01

    Jaw morphogenesis depends on the growth of Meckel’s cartilage during embryogenesis. However, the cell types and signals that promote chondrocyte proliferation for Meckel’s cartilage growth are poorly defined. Here we show that neural crest cells (NCCs) and their derivatives provide an essential source of the vascular endothelial growth factor (VEGF) to enhance jaw vascularization and stabilize the major mandibular artery. We further show in two independent mouse models that blood vessels promote Meckel’s cartilage extension. Coculture experiments of arterial tissue with NCCs or chondrocytes demonstrated that NCC-derived VEGF promotes blood vessel growth and that blood vessels secrete factors to instruct chondrocyte proliferation. Computed tomography and X-ray scans of patients with hemifacial microsomia also showed that jaw hypoplasia correlates with mandibular artery dysgenesis. We conclude that cranial NCCs and their derivatives provide an essential source of VEGF to support blood vessel growth in the developing jaw, which in turn is essential for normal chondrocyte proliferation, and therefore jaw extension. PMID:25922531

  2. The evolutionary origin of jaw yaw in mammals

    PubMed Central

    Grossnickle, David M.

    2017-01-01

    Theria comprises all but three living mammalian genera and is one of the most ecologically pervasive clades on Earth. Yet, the origin and early history of therians and their close relatives (i.e., cladotherians) remains surprisingly enigmatic. A critical biological function that can be compared among early mammal groups is mastication. Morphometrics and modeling analyses of the jaws of Mesozoic mammals indicate that cladotherians evolved musculoskeletal anatomies that increase mechanical advantage during jaw rotation around a dorsoventrally-oriented axis (i.e., yaw) while decreasing the mechanical advantage of jaw rotation around a mediolaterally-oriented axis (i.e., pitch). These changes parallel molar transformations in early cladotherians that indicate their chewing cycles included significant transverse movement, likely produced via yaw rotation. Thus, I hypothesize that cladotherian molar morphologies and musculoskeletal jaw anatomies evolved concurrently with increased yaw rotation of the jaw during chewing cycles. The increased transverse movement resulting from yaw rotation may have been a crucial evolutionary prerequisite for the functionally versatile tribosphenic molar morphology, which underlies the molars of all therians and is retained by many extant clades. PMID:28322334

  3. Fossil jawless fish from China foreshadows early jawed vertebrate anatomy.

    PubMed

    Gai, Zhikun; Donoghue, Philip C J; Zhu, Min; Janvier, Philippe; Stampanoni, Marco

    2011-08-17

    Most living vertebrates are jawed vertebrates (gnathostomes), and the living jawless vertebrates (cyclostomes), hagfishes and lampreys, provide scarce information about the profound reorganization of the vertebrate skull during the evolutionary origin of jaws. The extinct bony jawless vertebrates, or 'ostracoderms', are regarded as precursors of jawed vertebrates and provide insight into this formative episode in vertebrate evolution. Here, using synchrotron radiation X-ray tomography, we describe the cranial anatomy of galeaspids, a 435-370-million-year-old 'ostracoderm' group from China and Vietnam. The paired nasal sacs of galeaspids are located anterolaterally in the braincase, and the hypophyseal duct opens anteriorly towards the oral cavity. These three structures (the paired nasal sacs and the hypophyseal duct) were thus already independent of each other, like in gnathostomes and unlike in cyclostomes and osteostracans (another 'ostracoderm' group), and therefore have the condition that current developmental models regard as prerequisites for the development of jaws. This indicates that the reorganization of vertebrate cranial anatomy was not driven deterministically by the evolutionary origin of jaws but occurred stepwise, ultimately allowing the rostral growth of ectomesenchyme that now characterizes gnathostome head development.

  4. The evolutionary origin of jaw yaw in mammals.

    PubMed

    Grossnickle, David M

    2017-03-21

    Theria comprises all but three living mammalian genera and is one of the most ecologically pervasive clades on Earth. Yet, the origin and early history of therians and their close relatives (i.e., cladotherians) remains surprisingly enigmatic. A critical biological function that can be compared among early mammal groups is mastication. Morphometrics and modeling analyses of the jaws of Mesozoic mammals indicate that cladotherians evolved musculoskeletal anatomies that increase mechanical advantage during jaw rotation around a dorsoventrally-oriented axis (i.e., yaw) while decreasing the mechanical advantage of jaw rotation around a mediolaterally-oriented axis (i.e., pitch). These changes parallel molar transformations in early cladotherians that indicate their chewing cycles included significant transverse movement, likely produced via yaw rotation. Thus, I hypothesize that cladotherian molar morphologies and musculoskeletal jaw anatomies evolved concurrently with increased yaw rotation of the jaw during chewing cycles. The increased transverse movement resulting from yaw rotation may have been a crucial evolutionary prerequisite for the functionally versatile tribosphenic molar morphology, which underlies the molars of all therians and is retained by many extant clades.

  5. Jaw muscle afferent firing during an isotonic jaw-positioning task in the monkey.

    PubMed

    Larson, C R; Finocchio, D V; Smith, A; Luschei, E S

    1983-07-01

    The activity of jaw muscle receptors was studied by recording neurons in the mesencephalic nucleus of the trigeminal nerve in monkeys trained to control the position and movement of their mandible. Jaw position was measured by a weighted lever resting on the mandibular incisors. The force required to maintain the position of the lever was varied; in most cases it was either 25 or 360 g. Firing rates of neurons were related to stationary mandibular positions and to the velocity of movements during intervals when the movement velocity was constant. Of 49 neurons studied in detail, 21 fired at rates that were consistently and linearly related to static incisal openings. This static position sensitivity was typically about 5 spikes/mm of incisal opening. Most position-sensitive neurons fired at higher rates during opening movements and at lower rates during closing movements than would be accounted for by their position sensitivity. This sensitivity to the velocity of movement was not linear, however; slow closing movements sometimes did not produce a decrease in firing rate, and an actual increase during muscle shortening was seen in a few instances. The position sensitivity of eight neurons was evaluated during different loading conditions; in no case did it change substantially. Of the remaining 28 neurons, 26 fired at high rates during all opening movements and either stopped firing or fired at low, sporadic rates during closing movements. The static position sensitivity of these neurons was weak and variable both within and between neurons. The velocity sensitivity of these stretch-sensitive neurons was very nonlinear. Except for a range of slow movements (+/- 5 mm/s), the firing rate was maximal (200 spikes/s or higher) for most opening movements and zero for most closing movements. Maximal firing rates were higher when the loads being moved were increased from 25 to 360 g. The majority of position-sensitive neurons exhibited a large interspike

  6. Telescopic Partial Dentures-Concealed Technology

    PubMed Central

    Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

    2015-01-01

    The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of “floating plastic” in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental implants or fixed partial denture is the better options, but they have certain limitations. However, overdentures and particularly telescopic denture is the overlooked technology in dentistry that would be a boon for such needy patients. Telescopic denture is especially indicated in the distal edentulous area with minimum two teeth bilaterally present with a good amount of periodontal support. This treatment modality is sort of preventive prosthodontics remedy, which in a conservative manner preserve the remaining teeth and helps in conservation of alveolar bone ultimately. There are two tenets related to this option, one is constant conservation edentulous ridge around the retained tooth and the most important is the endless existence of periodontal sensory action that directs and monitor gnathodynamic task. In this option the primary coping or inner coping are cemented on the prepared tooth, and a similar removable outer or inner telescopic crown placed tightly by using a mechanism of tenso-friction, this is firmly attached to a removable RPD in place without moving or rocking of the prosthesis, which is the common compliant of almost all patients of RPD. Copings are also protecting the abutment from tooth decay and also offers stabilization and maintaining of the outer crown. The outer crown engages the inner coping and gives as an anchor for the remainder of the dentition. This work is the review of telescopic prosthesis which is well supported by the case discussion, and

  7. Micro- and macroevolutionary decoupling of cichlid jaws: a test of Liem's key innovation hypothesis.

    PubMed

    Hulsey, C D; García de León, F J; Rodiles-Hernández, R

    2006-10-01

    The extent to which elements of functional systems can change independently (modularity) likely influences the diversification of lineages. Major innovations in organismal design, like the pharyngeal jaw in cichlid fishes, may be key to a group's success when they relax constraints on diversification by increasing phenotypic modularity. In cichlid fishes, pharyngeal jaw modifications that enhanced the ability to breakdown prey may have freed their oral jaws from serving their ancestral dual role as a site of both prey capture and prey processing. This functional decoupling that allowed the oral jaws to become devoted solely to prey capture has been hypothesized to have permitted the two sets of cichlid jaws to evolve independently. We tested the hypothesis that oral and pharyngeal jaw mechanics are evolutionarily decoupled both within and among Neotropical Heroine cichlids. In the trophically polymorphic species Herichthys minckleyi, molariforms that exhibit enlarged molarlike pharyngeal jaw teeth were found to have approximately 400% greater lower jaw mass compared to H. minckleyi with the alternative papilliform pharyngeal morphology. However, oral jaw gape, lower jaw velocity ratios, anterior jaw linkage mechanics, and jaw protrusion did not differ between the morphotypes. In 40 other Heroine species, there was a weak correlation between oral jaw mechanics and pharyngeal jaw mass when phylogenetic history was ignored. Yet, after expansion of the cytochrome b phylogeny for Heroines, change in oral jaw mechanics was found to be independent of evolutionary change in pharyngeal jaw mass based on independent contrasts. Evolutionary decoupling of oral and pharyngeal jaw mechanics has likely played a critical role in the unparalleled trophic diversification of cichlid fishes.

  8. Jaw-opening accuracy is not affected by masseter muscle vibration in healthy men.

    PubMed

    Wiesinger, B; Häggman-Henrikson, B; Wänman, A; Lindkvist, M; Hellström, F

    2014-11-01

    There is a functional integration between the jaw and neck regions with head extension-flexion movements during jaw-opening/closing tasks. We recently reported that trigeminal nociceptive input by injection of hypertonic saline into the masseter muscle altered this integrated jaw-neck function during jaw-opening/closing tasks. Thus, in jaw-opening to a predefined position, the head-neck component increased during pain. Previous studies have indicated that muscle spindle stimulation by vibration of the masseter muscle may influence jaw movement amplitudes, but the possible effect on the integrated jaw-neck function is unknown. The aim of this study was to investigate the effect of masseter muscle vibration on jaw-head movements during a continuous jaw-opening/closing task to a target position. Sixteen healthy men performed two trials without vibration (Control) and two trials with bilateral masseter muscle vibration (Vibration). Movements of the mandible and the head were registered with a wireless three-dimensional optoelectronic recording system. Differences in jaw-opening and head movement amplitudes between Control and Vibration, as well as achievement of the predefined jaw-opening target position, were analysed with Wilcoxon's matched pairs test. No significant group effects from vibration were found for jaw or head movement amplitudes, or in the achievement of the target jaw-opening position. A covariation between the jaw and head movement amplitudes was observed. The results imply a high stability for the jaw motor system in a target jaw-opening task and that this task was achieved with the head-neck and jaw working as an integrated system.

  9. Predictable Technique to Register Retruded Contact Position (RCP) Using a Disposable Jaw Relation Recording Device.

    PubMed

    Daher, Tony; Lobel, William A; Massad, Joseph; Ahuja, Swati; Danilov, Zarko Jack

    2015-05-01

    The dental literature presents various definitions and techniques to describe and register centric relation (CR) or centric occlusion (CO). Briefly reviewing the literature in relation to CR, this article proposes the use of the term retruded contact position (RCP), clinically defined as retruded, unstrained, repeatable position and where the mandibular movements start when a Gothic arch tracing is used. With this clinical definition, a technique can be easily selected that meets all the requirements of such position. The article discusses the use of a jaw recorder that is an intraorally graphic recording device that results in a tracing of mandibular movements in one plane, with the apex of the tracing indicating the retruded, unstrained, and repeatable relationship. The intersection of the arcs produced by the right and left working movement form the apex of the Gothic arch tracing. Several clinical situations using the jaw recorder are described. Clinicians can now quickly and accurately record RCP, balance complete, partial, or implant dentures, and orthopedically reposition the mandible. The technique achieves highly reliable and reproducible results.

  10. Bioengineered Dental Tissues Grown in the Rat Jaw

    PubMed Central

    Duailibi, S.E.; Duailibi, M.T.; Zhang, W.; Asrican, R.; Vacanti, J.P.; Yelick, P.C.

    2009-01-01

    Our long-term objective is to develop methods to form, in the jaw, bioengineered replacement teeth that exhibit physical properties and functions similar to those of natural teeth. Our results show that cultured rat tooth bud cells, seeded onto biodegradable scaffolds, implanted into the jaws of adult rat hosts and grown for 12 weeks, formed small, organized, bioengineered tooth crowns, containing dentin, enamel, pulp, and periodontal ligament tissues, similar to identical cell-seeded scaffolds implanted and grown in the omentum. Radiographic, histological, and immunohistochemical analyses showed that bioengineered teeth consisted of organized dentin, enamel, and pulp tissues. This study advances practical applications for dental tissue engineering by demonstrating that bioengineered tooth tissues can be regenerated at the site of previously lost teeth, and supports the use of tissue engineering strategies in humans, to regenerate previously lost and/or missing teeth. The results presented in this report support the feasibility of bioengineered replacement tooth formation in the jaw. PMID:18650546

  11. Jaw osteonecrosis in patients treated with bisphosphonates: an ultrastructural study.

    PubMed

    Perrotta, I; Cristofaro, M G; Amantea, M; Russo, E; De Fazio, S; Zuccalà, V; Conforti, F; Amorosi, A; Donato, G; Tripepi, S; Giudice, M

    2010-08-01

    Osteonecrosis of the jaw is a severe bone disorder traditionally associated with periodontal disease, local malignancy, chemotherapy, glucocorticoid therapy, or trauma. Recently a growing number of publications reported the occurrence of osteonecrosis of the jaw in patients undergoing treatment with bisphosphonates. The mechanism by which bisphosphonates might contribute to the development of osteonecrosis of the jaw is far from being fully elucidated. Suppression of bone turnover, infection, tissue hypoxia and cellular toxicity were proposed as possible mechanisms by which bisphosphonates may exert adverse effects on bone metabolism. Here, we studied 25 consecutive patients treated with bisphosphonates for osteoporosis or tumoral pathologies. We provide good evidence of hyperactive osteoclastic bone resorption and suggest a direct cytotoxic effect of bisphosphonates on bone tissue through induction of osteocyte cell death. We also demonstrate that bisphosphonates only have limited adverse effects on bone vascular network.

  12. Adalimumab: Another Medication Related to Osteonecrosis of the Jaws?

    PubMed Central

    Cassoni, Andrea; Romeo, Umberto; Terenzi, Valentina; Della Monaca, Marco; Rajabtork Zadeh, Oriana; Raponi, Ingrid; Fadda, Maria Teresa; Polimeni, Antonella; Valentini, Valentino

    2016-01-01

    Objective. The acronym MRONJ has been created in order to identify “Medication-Related Osteonecrosis of the Jaw,” observed after the use of Bisphosphonates, RANK ligand inhibitor, and antiangiogenic medications. Only a case of osteonecrosis of the jaw in a Chron's disease patient following a course of Bisphosphonate and Adalimumab therapy has been recently described, so that it has been supposed that also this medication could promote manifestation of osteonecrosis. Clinical Case. On August, 2014, a 63-year-old female with a history of idiopathic arthritis treated with medical treatment with Adalimumab from 2010 to 2013 presented referring pain in the right mandible. Results. This patient presented with nonexposed osteonecrosis of the jaw after placement, on September, 2010, of four titanium fixtures in the mandible. Conclusions. The authors suggest that the biologic therapy with an anti-TNF-α antibody might promote the manifestation of osteonecrosis and compromise oral healing capacity of the bone. PMID:27088019

  13. Adalimumab: Another Medication Related to Osteonecrosis of the Jaws?

    PubMed

    Cassoni, Andrea; Romeo, Umberto; Terenzi, Valentina; Della Monaca, Marco; Rajabtork Zadeh, Oriana; Raponi, Ingrid; Fadda, Maria Teresa; Polimeni, Antonella; Valentini, Valentino

    2016-01-01

    Objective. The acronym MRONJ has been created in order to identify "Medication-Related Osteonecrosis of the Jaw," observed after the use of Bisphosphonates, RANK ligand inhibitor, and antiangiogenic medications. Only a case of osteonecrosis of the jaw in a Chron's disease patient following a course of Bisphosphonate and Adalimumab therapy has been recently described, so that it has been supposed that also this medication could promote manifestation of osteonecrosis. Clinical Case. On August, 2014, a 63-year-old female with a history of idiopathic arthritis treated with medical treatment with Adalimumab from 2010 to 2013 presented referring pain in the right mandible. Results. This patient presented with nonexposed osteonecrosis of the jaw after placement, on September, 2010, of four titanium fixtures in the mandible. Conclusions. The authors suggest that the biologic therapy with an anti-TNF-α antibody might promote the manifestation of osteonecrosis and compromise oral healing capacity of the bone.

  14. Reflex control of human jaw muscles.

    PubMed

    Türker, Kemal S

    2002-01-01

    The aim of this review is to discuss what is known about the reflex control of the human masticatory system and to propose a method for standardized investigation. Literature regarding the current knowledge of activation of jaw muscles, receptors involved in the feedback control, and reflex pathways is discussed. The reflexes are discussed under the headings of the stimulation conditions. This was deliberately done to remind the reader that under each stimulation condition, several receptor systems are activated, and that it is not yet possible to stimulate only one afferent system in isolation in human mastication experiments. To achieve a method for uniform investigation, we need to set a method for stimulation of the afferent pathway under study with minimal simultaneous activation of other receptor systems. This stimulation should also be done in an efficient and reproducible way. To substantiate our conviction to standardize the stimulus type and parameters, we discuss the advantages and disadvantages of mechanical and electrical stimuli. For mechanical stimulus to be delivered in a reproducible way, the following precautions are suggested: The stimulus delivery system (often a probe attached to a vibrator) should be brought into secure contact with the area of stimulation. To minimize the slack between the probe, the area to be stimulated should be taken up by the application of pre-load, and the delivered force should be recorded in series. Electrical stimulus has advantages in that it can be delivered in a reproducible way, though its physiological relevance can be questioned. It is also necessary to standardize the method for recording and analyzing the responses of the motoneurons to the stimulation. For that, a new technique is introduced, and its advantages over the currently used methods are discussed. The new method can illustrate the synaptic potential that is induced in the motoneurons without the errors that are unavoidable in the current

  15. Why do edentulous adults with intellectual disabilities not wear dentures? Wave 2 of the IDS TILDA cohort study.

    PubMed

    Mac Giolla Phadraig, Caoimhin; Nunn, June; Carroll, Rachael; McCarron, Mary; McCallion, Philip

    2017-01-01

    Older adults with intellectual disabilities (ID) are often edentulous. When total tooth loss occurs, they are very unlikely to wear complete removable dentures (CRDs) to restore oral function in Ireland. The reasons for this are unclear, though opinion holds that this is because dentists do not offer prosthodontic treatment to this group. In this study we ask edentulous older adults with ID why they do not wear dentures. Cross-sectional survey data from Wave 2 of the Intellectual Disability Supplement to The Irish Longitudinal Study on Ageing (IDS-TILDA) was examined to study reported denture wear among edentulous older adults with ID. Out of 692 participants, 186 were edentulous (26.9%), of whom 57 (30.6%) wore CRDs and 129 (69.3%) did not. Twelve of this 129 had dentures but did not wear them. Of the 117 respondents who reported that they did not have dentures, 99 (valid %=92.5%) did not want dentures, while only 8 did. No respondents in this study reported that they were denied denture therapy. Rather, they simply did not want dentures. Clinicians should understand that extra steps may be needed to ensure that consent is truly informed when patients opt for, or decline, complete denture therapy. While there is a high normative need for prosthodontic rehabilitation, expressed need is low. Extra steps may be necessary to ensure optimal outcomes for people with ID. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  16. Record base for an edentulous maxillary arch with severe undercuts in the labial aspect of the anterior residual ridge.

    PubMed

    Nishigawa, Goro; Maruo, Yukinori; Okamoto, Makoto; Minagi, Shogo

    2002-01-01

    A procedure is described for the fabrication of a record base for an edentulous maxillary arch with severe undercuts in the labial aspect of the anterior residual ridge. The record base is fabricated from autopolymerizing resin without soft lining materials and without blockout of the labial undercut of the stone cast.

  17. Edentulism associates with worse cognitive performance in community-dwelling elders in rural Ecuador: results of the Atahualpa project.

    PubMed

    Del Brutto, Oscar H; Gardener, Hannah; Del Brutto, Victor J; Maestre, Gladys E; Zambrano, Mauricio; Montenegro, Jipson E; Wright, Clinton B

    2014-12-01

    Studies in industrialized nations suggest that severe edentulism correlates with cognitive impairment, but there is little information on this association in underserved populations. We conducted a community-based study to assess whether edentulism associates with cognitive impairment in elders living in rural Ecuador. Atahualpa residents aged ≥60 years were identified during a door-to-door census and evaluated using the Montreal Cognitive Assessment (MoCA). Persons were classified into two groups according to whether they have severe edentulism (<10 remaining teeth) or not. In addition, a questionnaire allowed self-rating of oral health. A total of 274 persons (mean age 69.6 ± 7.7 years; 59% women) were included. Persons with <10 remaining teeth (n = 116) have significantly lower MoCA scores than those with ≥10 teeth (n =158), after adjusting for demographics, cardiovascular risk factors, depression and dementia (β = -1.06, p = 0.03). Self-rated poor oral health was more prevalent among persons with <10 teeth (p < 0.0001), but did not correlate with MoCA scores (good vs. poor, β = -0.89, p = 0.89). Severe edentulism is associated with poor cognitive performance in elders living in rural Ecuador. Public health campaigns directed to improve oral health may facilitate early recognition of persons with cognitive impairment in underserved populations.

  18. The origin and early phylogenetic history of jawed vertebrates.

    PubMed

    Brazeau, Martin D; Friedman, Matt

    2015-04-23

    Fossils of early gnathostomes (or jawed vertebrates) have been the focus of study for nearly two centuries. They yield key clues about the evolutionary assembly of the group's common body plan, as well the divergence of the two living gnathostome lineages: the cartilaginous and bony vertebrates. A series of remarkable new palaeontological discoveries, analytical advances and innovative reinterpretations of existing fossil archives have fundamentally altered a decades-old consensus on the relationships of extinct gnathostomes, delivering a new evolutionary framework for exploring major questions that remain unanswered, including the origin of jaws.

  19. Implant support for removable partial overdentures: a case report.

    PubMed

    Halterman, S M; Rivers, J A; Keith, J D; Nelson, D R

    1999-01-01

    Functional stability and the preservation of remaining alveolar bone are primary, and often elusive, goals when restoring the partially edentulous arch. The incorporation of dental implants for the partial support of removable prostheses offers a practical adjunct in the fulfillment of these objectives. Planning for complex courses of treatment that include dental implants requires close coordination between the surgeon and the restorative dentist. Decisions that deal with type, location, size, number of implant fixtures, and design of the prosthesis are critical. All of these areas must be discussed and established as acceptable to the patient and each clinician before the initiation of treatment. In this report, we present a course of patient treatment in which a removable partial denture is supported by natural remaining teeth in conjunction with osseointegrated implants.

  20. A dynamic model of mouth closing movements in clariid catfishes: the role of enlarged jaw adductors.

    PubMed

    Van Wassenbergh, Sam; Aerts, Peter; Adriaens, Dominique; Herrel, Anthony

    2005-05-07

    Some species of Clariidae (air breathing catfishes) have extremely large (hypertrophied) jaw closure muscles. Besides producing higher bite forces, the enlarged muscles may also cause higher accelerations of the lower jaw during rapid mouth closure. Thus, jaw adductor hypertrophy could potentially also enable faster mouth closure. In this study, a forward dynamic model of jaw closing is developed to evaluate the importance of jaw adductor hypertrophy on the speed of mouth closure. The model includes inertia, pressure, tissue resistance and hydrodynamic drag forces on the lower jaw, which is modelled as a rotating half-ellipse. Simulations are run for four clariid species showing a gradual increase in jaw adductor hypertrophy (Clarias gariepinus, Clariallabes longicauda, Gymnallabes typus and Channallabes apus). The model was validated using data from high-speed videos of prey captures in these species. In general, the kinematic profiles of the fastest mouth closure from each species are reasonably well predicted by the model. The model was also used to compare the four species during standardized mouth closures (same initial gape angle, travel distance and cranial size). These simulations suggest that the species with enlarged jaw adductors have an increased speed of jaw closure (in comparison with the non-hypertrophied C. gariepinus) for short lower jaw rotations and when feeding at high gape angles. Consequently, the jaw system in these species seems well equipped to capture relatively large, evasive prey. For prey captures during which the lower jaw rotates freely over a larger distance before impacting the prey, the higher kinematic efficiency of the C. gariepinus jaw system results in the fastest jaw closures. In all cases, the model predicts that an increase in the physiological cross-sectional area of the jaw muscles does indeed contribute to the speed of jaw closure in clariid fish.

  1. A Systematic Review of the Role of Implant Design in the Rehabilitation of the Edentulous Maxilla.

    PubMed

    Jokstad, Asbjørn; Sanz, Mariano; Ogawa, Takahiro; Bassi, Francesco; Levin, Liran; Wennerberg, Ann; Romanos, Georgios E

    2016-01-01

    To identify and critically appraise scientific publications evaluating the possible effect of implant design on treatment outcomes in the rehabilitation of patients with a fully edentulous maxilla. Scientific reports were sought in three electronic bibliographic databases, combined with searches for meeting abstracts, and in the grey literature. English, German, or Scandinavian scientific publications on prospective or retrospective longitudinal studies with effects of an implant design or feature on the treatment outcomes were eligible. Minimum requirement for inclusion was at least 10 study participants who were followed up for at least 2 years after implant loading. The PRISMA guidelines were followed for selecting data to extract from the individual studies. These were characteristics of the individual studies, risk of bias within individual studies, and the results of individual studies. Three editorial teams independently identified and extracted the data. The search resulted in 998 primary studies, of which 525 met the inclusion criteria and were read in full text. Of these, 105 studies were included in qualitative syntheses. Seventeen studies were designed with an objective to assess effects of implant design or feature on outcomes, 23 studies described tilted implants to enable placement of longer implants, 30 studies reported effects of implants placed in zygomatic bone with or without additional alveolar implants, and 9 studies reported effects of implants placed in pterygoid bone or other bony buttresses with or without additional alveolar implants. Sixteen articles reported bone augmentation with simultaneous or delayed implant placement in patients with a predominantly Cawood-Howell bone class V and VI maxilla. Ten papers reported effects of implant design on outcomes, despite the lack of an a priori stated objective to assess a particular implant design or feature. There is a lack of compelling data to state that one particular implant system or

  2. Implant loading protocols for edentulous patients with fixed prostheses: a systematic review and meta-analysis.

    PubMed

    Papaspyridakos, Panos; Chen, Chun-Jung; Chuang, Sung-Kiang; Weber, Hans-Peter

    2014-01-01

    To report on the effect of immediate implant loading with fixed prostheses compared to early and conventional loading on implant and prosthesis survival, failure, and complications. An electronic and manual search was conducted to identify randomized controlled clinical trials (RCTs) as well as prospective and retrospective studies involving rough surface implants and implant fixed complete dental prostheses for edentulous patients. The 62 studies that fulfilled the inclusion criteria featured 4 RCTs, 2 prospective case-control studies, 34 prospective cohort studies, and 22 retrospective cohort studies. These studies yielded data from 2,695 patients (2,757 edentulous arches) with 13,653 implants. Studies were grouped according to the loading protocol applied; 45 studies reported on immediate loading, 8 on early loading, and 11 on conventional loading. For the immediate loading protocol with flap surgery, the implant and prosthesis survival rates ranged from 90.1% to 100% and 93.75% to 100%, respectively (range of follow-up, 1 to 10 years). When immediate loading was combined with guided flapless implant placement, the implant survival rates ranged from 90% to 99.4%. For the early loading protocol, the implant and prosthesis survival rates ranged from 94.74% to 100% and 93.75% to 100%, respectively (range of follow-up, 1 to 10 years). For the conventional loading protocol, the implant and prosthesis survival rates ranged from 94.95% to 100% and 87.5% to 100%, respectively (range of follow-up, 2 to 15 years). No difference was identified between maxilla and mandible. When selecting cases carefully and using dental implants with a rough surface, immediate loading with fixed prostheses in edentulous patients results in similar implant and prosthesis survival and failure rates as early and conventional loading. For immediate loading, most of the studies recommended a minimal insertion torque of 30 Ncm. The estimated 1-year implant survival was above 99% with all three

  3. A survey of removable partial denture casts and major connector designs found in commercial laboratories, Athens, Greece.

    PubMed

    Polychronakis, Nick; Sotiriou, Michael; Zissis, Alcibiades

    2013-04-01

    This survey was conducted to study the prevalence of partial edentulism, the type of removable partial denture (RPD) support, the type of major connectors, and the frequency of their use in relation to the partial edentulism classes encountered, concerning patients in Athens, Greece. The material comprised 628 final casts for RPDs. Each cast was photographed in a way that would allow the number of existing teeth, the classification of partial edentulism, the RPD support, and the particular parts of the metal framework to be identified. Data collected were analyzed statistically using prevalence tables and the χ(2) test. Two hundred seventy six (43.9%) casts were for the maxilla and 352 (56.1%) for the mandible. The most frequently encountered group was Kennedy class I for both arches, while class IV was the classification least encountered (p < 0.001). Of all RPDs constructed, 96.8% had a metal framework (tooth-borne and tooth/tissue-borne), while 3.2% of the RPDs were frameless (tissue-borne, acrylic dentures). The U-shaped palatal connector (horseshoe) in the maxilla and the lingual bar in the mandible were the most frequently used for all partial edentulism classes, at 55.2% and 95%, respectively. Analysis of the casts revealed that the type of major connectors selected does not comply with the indications for their applications, considering the lack of dental history and clinical examination. This notes the need for further training dentists and dental technicians in aspects of RPD framework design. © 2013 by the American College of Prosthodontists.

  4. The relationships among jaw-muscle fiber architecture, jaw morphology, and feeding behavior in extant apes and modern humans.

    PubMed

    Taylor, Andrea B; Vinyard, Christopher J

    2013-05-01

    The jaw-closing muscles are responsible for generating many of the forces and movements associated with feeding. Muscle physiologic cross-sectional area (PCSA) and fiber length are two architectural parameters that heavily influence muscle function. While there have been numerous comparative studies of hominoid and hominin craniodental and mandibular morphology, little is known about hominoid jaw-muscle fiber architecture. We present novel data on masseter and temporalis internal muscle architecture for small- and large-bodied hominoids. Hominoid scaling patterns are evaluated and compared with representative New- (Cebus) and Old-World (Macaca) monkeys. Variation in hominoid jaw-muscle fiber architecture is related to both absolute size and allometry. PCSAs scale close to isometry relative to jaw length in anthropoids, but likely with positive allometry in hominoids. Thus, large-bodied apes may be capable of generating both absolutely and relatively greater muscle forces compared with smaller-bodied apes and monkeys. Compared with extant apes, modern humans exhibit a reduction in masseter PCSA relative to condyle-M1 length but retain relatively long fibers, suggesting humans may have sacrificed relative masseter muscle force during chewing without appreciably altering muscle excursion/contraction velocity. Lastly, craniometric estimates of PCSAs underestimate hominoid masseter and temporalis PCSAs by more than 50% in gorillas, and overestimate masseter PCSA by as much as 30% in humans. These findings underscore the difficulty of accurately estimating jaw-muscle fiber architecture from craniometric measures and suggest models of fossil hominin and hominoid bite forces will be improved by incorporating architectural data in estimating jaw-muscle forces. Copyright © 2013 Wiley Periodicals, Inc.

  5. Jaw avascular osteonecrosis after treatment of multiple myeloma with zoledronate.

    PubMed

    Lobato, J V; Maurício, A C; Rodrigues, J M; Cavaleiro, M V; Cortez, P P; Xavier, L; Botelho, C; Hussain, N Sooraj; Santos, J D

    2008-01-01

    of metastatic disease evaluated by biopsy. In these three described clinical cases, surgical debridment without flap elevation, intensive antibiotherapy and the suspension of the zoledronate treatment allowed a partial recovery of the patients. The purpose of this clinical report is to point out that patients suffering from multiple myeloma can develop bone osteonecrosis induced by treatment with bisphosphonates. Research to determine the mechanism of this dental phenomenon is needed to fully validate and substantiate the possible link between bisphosphonate treatment of multiple myeloma or other cancer diseases and avascular osteonecrosis of the jaws. Until then, clinicians involved in the care of patients at risk should consider this possible complication.

  6. A study of the emotional effects of tooth loss in an edentulous Gujarati population and its association with depression

    PubMed Central

    Shah, Rupal J.; Diwan, Fatema J.; Diwan, Munira J.; Chauhan, Vishal J.; Agrawal, Hemal S.; Patel, Ghanshyam C.

    2015-01-01

    Context: To fully estimate the burden of illness due to edentulism and establish valid treatment outcomes measures in this regard, it is equally important to study its psychosocial repercussions. Aims: The aim was to conduct a study to explore the emotional reactions to tooth loss, screen for current depressive symptoms and test for association between the two; among an edentulous Gujarati population. Settings and Design: A total of 147 edentulous people visiting the Prosthodontics Department were surveyed. Subjects and Methods: A questionnaire (based on previous studies) to test the emotional reactions to tooth loss and Nine Item-Patient Health Questionnaire to test for depression were used. Statistical Analysis Used: The data were analyzed using the Chi-square (χ2) test with the help of SPSS v. 18.0 (IBM Corp., Armonk, NY, USA). Results: Totally, 100 out of 147 edentulous people returned the questionnaire of which 58% experienced difficulties in accepting tooth loss and 37% felt unprepared for its effects. Those with difficulties accepting tooth loss had a greater effect on self esteem and social life, had more reservation about discussing tooth loss and was more likely to experience depression. Both groups were satisfied with dentures, had no problem meeting their friends or partners without dentures and leaving out dentures at night. Conclusion: About 58% of edentulous people had difficulties accepting tooth loss, which was unrelated to denture satisfaction. Respondents appeared to be restricted in social activities mainly due to functional limitations. Those with difficulties accepting tooth loss were more likely to experience depression. PMID:26929519

  7. Bisphosphonate-related osteonecrosis of the jaws: a single-center study of 101 patients.

    PubMed

    Lazarovici, Towy Sorel; Yahalom, Ran; Taicher, Shlomo; Elad, Sharon; Hardan, Izhar; Yarom, Noam

    2009-04-01

    Osteonecrosis of the jaw (ONJ) is a devastating side effect of long-term bisphosphonate (BP) use. We present the largest case series from a single department. This case series included 101 ONJ patients. Data on demographics, medical background, type and duration of BP use, possible triggering events, mode of therapy, and outcome were recorded. ONJ was associated with intravenous BPs in 85 patients and with oral BPs in 16 patients. It was diagnosed after 48, 27, and 67 months of pamidronate, zoledronic acid, and alendronate use, respectively. Long-term antibiotics and minimal surgical procedures resulted in complete or partial healing in 18% and 52% of the patients, respectively; 30% had no response. There was no association between ONJ and diabetes, steroid and antiangiogenic treatment, or underlying periodontal disease. Diagnostic biopsies aggravated lesions without being informative about pathogenesis. A conservative regimen is our treatment of choice. Solutions for decreasing morbidity and poor outcome of ONJ remain elusive.

  8. Establishment, maintenance and modifications of the lower jaw dentition of wild Atlantic salmon (Salmo salar L.) throughout its life cycle.

    PubMed

    Huysseune, Ann; Hall, Brian K; Witten, P Eckhard

    2007-10-01

    In this paper we elucidate the pattern of initiation of the first teeth and the pattern of tooth replacement on the dentary of wild Atlantic salmon (Salmo salar L.), throughout nearly all stages of its life cycle, using serially sectioned heads and jaws, cleared and stained animals, and X-rays. The dentary teeth are set in one row. Tooth germs appear around hatching, first in odd positions, followed by even positions. From position 8 further backwards, teeth are added in adjacent positions. The first replacement teeth appear in animals of about 30 mm fork length. On the dentary of early life stages (alevins and fry), every position in the tooth row holds a functional (i.e. attached and erupted) tooth and a replacement tooth. The alternating pattern set up anteriorly in the dentary by the first-generation teeth changes in juveniles (parr) whereby teeth are in a similar functional (for the erupted teeth) or developmental stage (for the replacement teeth) every three positions. This pattern is also observed in marine animals during their marine life phase and in both sexes of adult animals prior to spawning (grilse and salmon), but every position now holds either a functional tooth or a mineralised replacement tooth. This is likely due to the fact that replacement tooth germs have to grow to a larger size before mineralisation starts. In the following spring, the dentary tooth pattern of animals that have survived spawning (kelts) is highly variable. The abundance of functional teeth in post-spawning animals nevertheless indicates that teeth are not lost over winter. We confirm the earlier reported lack of evidence for the existence of an edentulous life phase, preceding the appearance of so-called breeding teeth during upstream migration to the spawning grounds, and consider breeding teeth to be just another tooth generation in a regularly replacing dentition. This study shows how Atlantic salmon maintains a functional adaptive dentition throughout its complex life

  9. Establishment, maintenance and modifications of the lower jaw dentition of wild Atlantic salmon (Salmo salar L.) throughout its life cycle

    PubMed Central

    Huysseune, Ann; Hall, Brian K; Witten, P Eckhard

    2007-01-01

    In this paper we elucidate the pattern of initiation of the first teeth and the pattern of tooth replacement on the dentary of wild Atlantic salmon (Salmo salar L.), throughout nearly all stages of its life cycle, using serially sectioned heads and jaws, cleared and stained animals, and X-rays. The dentary teeth are set in one row. Tooth germs appear around hatching, first in odd positions, followed by even positions. From position 8 further backwards, teeth are added in adjacent positions. The first replacement teeth appear in animals of about 30 mm fork length. On the dentary of early life stages (alevins and fry), every position in the tooth row holds a functional (i.e. attached and erupted) tooth and a replacement tooth. The alternating pattern set up anteriorly in the dentary by the first-generation teeth changes in juveniles (parr) whereby teeth are in a similar functional (for the erupted teeth) or developmental stage (for the replacement teeth) every three positions. This pattern is also observed in marine animals during their marine life phase and in both sexes of adult animals prior to spawning (grilse and salmon), but every position now holds either a functional tooth or a mineralised replacement tooth. This is likely due to the fact that replacement tooth germs have to grow to a larger size before mineralisation starts. In the following spring, the dentary tooth pattern of animals that have survived spawning (kelts) is highly variable. The abundance of functional teeth in post-spawning animals nevertheless indicates that teeth are not lost over winter. We confirm the earlier reported lack of evidence for the existence of an edentulous life phase, preceding the appearance of so-called breeding teeth during upstream migration to the spawning grounds, and consider breeding teeth to be just another tooth generation in a regularly replacing dentition. This study shows how Atlantic salmon maintains a functional adaptive dentition throughout its complex life

  10. Osteonecrosis of the jaw in patients treated with denosumab for metastatic tumors to the bone: A series of thirteen patients.

    PubMed

    Owosho, Adepitan A; Blanchard, Ariel; Levi, Lauren; Kadempour, Arvin; Rosenberg, Haley; Yom, SaeHee K; Farooki, Azeez; Fornier, Monica; Huryn, Joseph M; Estilo, Cherry L

    2016-03-01

    This case series describes the course of osteonecrosis of the jaw (ONJ) in thirteen patients with metastatic bone tumors treated solely with denosumab. Patients on denosumab may be more prone to developing ONJ even without a risk/precipitating factor and they may develop ONJ early in their denosumab therapy. The outcomes of ONJ in ten patients following a period of denosumab discontinuation after the onset of ONJ were: 3 had complete resolution of symptoms, 4 patients' ONJ progressed, 2 patients' ONJ was unchanged and in 1 patient there was partial ONJ resolution. The role of drug discontinuation prior to an invasive dental procedure or after the onset of ONJ still remains debatable.

  11. On Comparing Two Different Tray-Holding Techniques for Edentulous Maxillary Impressions.

    PubMed

    Rignon-Bret, Christophe; Mushegyan, Vagan; Naveau, Adrien

    2016-01-01

    This study compared tissue three-dimensional (3D) displacements during the material setting phase of two maxillary impression tray-holding techniques: clinician manual pressure and patient occlusal pressure. The resultant two maxillary casts for each of 10 edentulous patients were compared using an optical 3D measurement system. The junction between the hard and soft palates acted like a rotation center during impression making. The vertical displacements were significantly lower and posteriorly set when the impression was taken with the patient's occlusion, in contrast to being located at the anterior two-thirds during the manual impression technique. Use of patient's occlusion as a tray-holding technique may be preferred during the material setting phase of maxillary impressions.

  12. [Review of scientific articles on complete edentulousness, published in the journal Fogorvosi Szemle].

    PubMed

    Kivovics, Péter; Gerle, János; Csadó, Kinga

    2009-08-01

    This publication is an assessment of scientific articles published in the Fogorvosi Szemle over the last 120 years dealing with the evolution of complete dentures and the treatment of complete edentulousness. Qualitative and quantitative analysis was performed to find the annual average number of scientific articles and to find the authors who published the most in this topic. Publications had been collected and categorized according to author, year and subject and an extensive comparative analysis was carried out. Nineteen authors had four or more first author publications during this time period. According to content, publications were divided into four major groups. Finally, the research activity of three academic scholars, Imre Kemény, Miklós Kaán and Géza Prágai, was introduced briefly based on their articles published in the Fogorvosi Szemle. All of them have contributed significantly to the scientific advance and the academic education of complete prosthetics.

  13. Elastic properties and apparent density of human edentulous maxilla and mandible.

    PubMed

    Seong, W-J; Kim, U-K; Swift, J Q; Heo, Y-C; Hodges, J S; Ko, C-C

    2009-10-01

    The aim of this study was to determine whether elastic properties and apparent density of bone differ in different anatomical regions of the maxilla and mandible. Additional analyses assessed how elastic properties and apparent density were related. Four pairs of edentulous maxilla and mandibles were retrieved from fresh human cadavers. Bone samples from four anatomical regions (maxillary anterior, maxillary posterior, mandibular anterior, mandibular posterior) were obtained. Elastic modulus (EM) and hardness (H) were measured using the nano-indentation technique. Bone samples containing cortical and trabecular bone were used to measure composite apparent density (cAD) using Archimedes' principle. Statistical analyses used repeated measures ANOVA and Pearson correlations. Bone physical properties differed between regions of the maxilla and mandible. Generally, mandible had higher physical property measurements than maxilla. EM and H were higher in posterior than in anterior regions; the reverse was true for cAD. Posterior maxillary cAD was significantly lower than that in the three other regions.

  14. Prosthodontic management of a completely edentulous patient with microstomia: a case report.

    PubMed

    Gauri, Mulay; Ramandeep, Dugal

    2013-09-01

    Patients with microstomia who need to wear removable dental prosthesis often face difficulty of being unable to insert or remove the prosthesis because of restricted opening of the oral cavity. Prosthetic rehabilitation of patients with microstomia presents difficulties in all the clinical steps. In such patients, it is difficult to make impressions and fabricate dentures using conventional method. This clinical report describes prosthodontic management of a completely edentulous patient with microstomia developed due to oral sub mucous fibrosis. Sectional maxillary denture was fabricated using a sectional impression tray technique. With the use of magnets and palatal midline press button attachment, the denture could be easily inserted and removed in two parts. Mandibular denture was fabricated by the conventional method.

  15. Mandibular subluxation for distal internal carotid artery exposure in edentulous patients.

    PubMed

    Jaspers, Gijs W; Witjes, Max J; van den Dungen, Jan J; Reintsema, Harry; Zeebregts, Clark J

    2009-12-01

    Four patients with high internal carotid artery (ICA) occlusive disease were indicated for surgical endarterectomy and needed additional exposure besides regular head rotation and extension. When indicated, in our clinic this is usually achieved by mandibular subluxation with interdental wiring. Due to dental wear and periodontal disease, all 4 patients were edentulous. As a consequence, the technique of interdental wiring could not be used. In this technical note we will explain a method for interarch fixation with the use of two ipsilateral monocortical miniscrews and wiring, and the use of patients' pre-existing mandibular implants and provisional overdenture. This method gives rise to an additional exposure of 15 to 20 mm of the ICA.

  16. Role of FNAC in the diagnosis of intraosseous jaw lesions

    PubMed Central

    Goyal, Surbhi; Kotru, Mrinalini; Gupta, Neelima

    2015-01-01

    Background FNAC of intraosseous jaw lesions has not been widely utilized for diagnosis due to rarity and diversity of these lesions, limited experience and lack of well established cytological features. Aim of the study was to determine the role of FNAC in the diagnosis of intraosseous jaw swellings. Material and Methods 42 patients underwent FNAC over a period of 7 years (2007-2013), of which 37 (88.1%) aspirates were diagnostic. Histopathology correlation was available in 33 cases and diagnostic accuracy of FNAC was calculated. Results Lesions were categorized into inflammatory 3, cysts/hamartomas 15 and neoplasms 19. Mandibular and maxillary involvement was seen in 21 and 16 patients respectively. Of these, benign cysts and malignant lesions were commonest, accounting for 27% lesions (10 cases) each. One case of cystic ameloblastoma was misdiagnosed as odontogenic cyst on cytology. Overall, sensitivity and specificity of FNAC were 94.7% and 100% respectively with a diagnostic accuracy of 97.3%. Definitive categorization of giant cell lesions, fibro-osseous lesions, odontogenic tumors and cystic lesions was not feasible on FNAC. Conclusions FNAC is a simple, safe and minimally invasive first line investigation which can render an accurate preoperative diagnosis of intraosseous jaw lesions, especially the malignant ones in the light of clinic-radiological correlation. Key words: Jaw swellings, intraosseous, FNAC. PMID:25662547

  17. 21 CFR 872.2060 - Jaw tracking device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... powered device that measures and records anatomical distances and angles in three dimensional space, to..., while at rest and during jaw movement. (2) Classification. Class I (general controls). The device is... position of the mandible in three dimensional space, with respect to the location and position of the...

  18. Jaw-Phonatory Coordination in Chronic Developmental Stuttering

    ERIC Educational Resources Information Center

    Loucks, Torrey M. J.; De Nil, Luc F.; Sasisekaran, Jayanthi

    2007-01-01

    A deficiency in sensorimotor integration in a person who stutters may be a factor in the pathophysiology of developmental stuttering. To test oral sensorimotor function in adults who stutter, we used a task that requires the coordination of a jaw-opening movement with phonation onset. The task was adapted from previous limb coordination studies,…

  19. The Sequential Development of Jaw and Lip Control for Speech

    PubMed Central

    Green, Jordan R.; Moore, Christopher A.; Reilly, Kevin J.

    2010-01-01

    Vertical displacements of the upper lip, lower lip, and jaw during speech were recorded for groups of 1-, 2-, and 6-year-olds and adults to examine if control over these articulators develops sequentially. All movement traces were amplitude- and time-normalized. The developmental course of upper lip, lower lip, and jaw control was examined by quantifying age-related changes in the similarity of each articulator's movement patterns to those produced by adult subjects and by same-age peers. In addition, differences in token-to-token stability of articulatory movement were assessed among the different age groups. The experimental findings revealed that 1- and 2-year-old children's jaw movements were significantly more adult-like than their upper and lower lip movements, which were more variable. In contrast, upper and lower lip movement patterns became more adult-like with maturation. These findings suggest that the earliest stages of speech motor development are constrained by the nonuniform development of articulatory control, with the jaw preceding the lips. The observed developmental patterns suggest that the properties of the oral motor control system significantly influence the pattern of speech sound acquisition. PMID:14748639

  20. Tongue-jaw kinematic correlates of /s/ spectra

    NASA Astrophysics Data System (ADS)

    Dembowski, James S.; Crumb, Richard K.

    2004-05-01

    Frequencies of spectral peaks for fricatives are determined by the size of the resonating cavity anterior to the place of articulatory constriction in the upper vocal tract. For /s/, this cavity size may be altered through anterior-posterior (a-p) movements of the tongue blade forming the constriction, changes of jaw height, and degree of lip protrusion. With respect to intensity, modeling studies suggest that intensity of fricative spectral peaks may be related to degree of articulatory constriction. These spectral-kinematic relationships have been little studied in natural speech. This study used data from the University of Wisconsin X-Ray Microbeam Database to examine the relationship between spectral peaks and movements of the tongue and jaw in the /s/ productions of one normal speaker. Results showed no relationship between a-p tongue position and frequency of spectral peaks. However, a significant inverse correlation related peak between frequency and jaw opening. Thus, for this speaker jaw height appeared a more important determinant of spectral variability for /s/ than tongue position. Additional results showed a significant relationship between peak intensity and distance of the tongue blade from the palate. These natural speech data will be discussed with respect to models and theories of fricative production.

  1. Embryology and Anatomy of the Jaw and Dentition.

    PubMed

    Zohrabian, Vahe M; Poon, Colin S; Abrahams, James J

    2015-10-01

    Radiologists should possess working knowledge of the embryological development and anatomy of the jaw and dentition in order to aid in the diagnosis of both simple and complex disorders that affect them. Here, we review the elaborate process of odontogenesis, as well as describe in detail the anatomy of a tooth and its surrounding structures.

  2. DETAIL VIEW OF ORE BINS AND JAW CRUSHER, LOOKING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF ORE BINS AND JAW CRUSHER, LOOKING NORTHWEST FROM NEARBY THE ENGINE. THE CONCRETE MACHINE PAD TO THE RIGHT OF THE CRUSHER PROBABLY HELD THE ENGINE THAT DROVE THE CRUSHER. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  3. 12. CLOSEUP OF THE CURRENT TRASH RAKELIFTING MECHANISM (CALLED 'JAWS' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. CLOSE-UP OF THE CURRENT TRASH RAKE-LIFTING MECHANISM (CALLED 'JAWS' BY THE PRESENT OPERATORS), LOOKING WEST. THIS EQUIPMENT WAS REMOVED IN AUTUMN OF 1996. - Washington Water Power Company Post Falls Power Plant, Middle Channel Powerhouse & Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  4. Jaw muscularization requires Dlx expression by cranial neural crest cells

    PubMed Central

    Heude, Églantine; Bouhali, Kamal; Kurihara, Yukiko; Kurihara, Hiroki; Couly, Gérard; Janvier, Philippe; Levi, Giovanni

    2010-01-01

    The origin of active predation in vertebrates is associated with the rise of three major, uniquely derived developmental characteristics of the head: (i) migratory cranial neural crest cells (CNCCs) giving rise to most skeletal skull elements; (ii) expression of Dlx genes by CNCCs in the Hox-free first pharyngeal arch (PA1); and (iii) muscularization of PA1 derivatives. Here we show that these three innovations are tightly linked. Expression of Dlx genes by CNCCs is not only necessary for head skeletogenesis, but also for the determination, differentiation, and patterning of cephalic myogenic mesoderm leading to masticatory muscle formation. In particular, inactivation of Dlx5 and Dlx6 in the mouse results in loss of jaw muscles. As Dlx5/6 are not expressed by the myogenic mesoderm, our findings imply an instructive role for Dlx5/6-positive CNCCs in muscle formation. The defect in muscularization does not result from the loss of mandibular identity observed in Dlx5/6−/− mice because masticatory muscles are still present in EdnRA−/− mutants, which display a similar jaw transformation. The genesis of jaws and their muscularization should therefore be seen as an integrated Dlx-dependent developmental process at the origin of the vertebrate head. The role of Dlx genes in defining gnathostome jaw identity could, therefore, be secondary to a more primitive function in the genesis of the oral skeletomuscular system. PMID:20534536

  5. Pediatric odontogenic tumor of the jaw - a case report.

    PubMed

    Muddana, Keerthi; Pasupula, Ajay Prakash; Dorankula, Shyam Prasad Reddy; Thokala, Madhusudan Rao; Muppallai, Jaya Nagendra Krishna

    2014-02-01

    Central jaw tumors (intra osseous) in children occur infrequently and few oral pathologists have had the opportunity or experience in diagnosing these lesions and predicting their biological behavior. Some children are not diagnosed correctly at the initial stages as having a neoplasm and are wrongly treated for infections by antibiotic administration. Subsequent to an unresponsive antibiotic therapy radiographs are taken to reveal a radiolucent or radio dense lesion in the jaws. Finally a tissue diagnosis becomes necessary in order to diagnose and initiate proper therapy. One among the central jaw tumors that occur infrequently in children is Ameloblastoma. It is often aggressive and destructive, with the capacity to attain great size, erode bone and invade adjacent structures. Ameloblastoma not only accounts for 1% of all tumors of maxilla and mandible but also 11% of all odontogenic tumors. It has a high percentage of local recurrence rate and possible malignant development when treated inadequately. Here we present a central jaw tumor in an 8-year-old child which was a case of unusually large plexiform ameloblastoma involving entire ramus up to the condyle, and part of body of the mandible.

  6. Osteonecrosis of the jaw associated with ziv-aflibercept

    PubMed Central

    Enzinger, Peter; McCleary, Nadine; Manon, Reshma; Villa, Alessandro; Treister, Nathaniel; Woo, Sook-Bin

    2016-01-01

    Medication-related osteonecrosis of the jaw (MRONJ) has been associated with medications that include bisphosphonates (BPs), denosumab, bevacizumab and sunitinib. Ziv-aflibercept is a recombinant human vascular endothelial growth factor (VEGF) receptor which has been used to treat patients with various advanced solid tumors. We report three patients without a history of the use of medications known to cause MRONJ presenting with jaw osteonecrosis typical for MRONJ following therapy with ziv-aflibercept. All patients had metastatic gastrointestinal cancer treated with ziv-aflibercept and were evaluated for MRONJ because of exposed bone in the oral cavity. None of the patients had received antiresorptive therapies or any other medication known to cause MRONJ, and none had received radiation therapy to the jaws. Patients were aged 43, 51, 63 and all were males. Patients received 7, 16 and 23 cycles of ziv-aflibercept treatment and developed necrotic bone. All three patients presented with mandibular involvement, with two reporting pain. Patients were managed with anti-microbial mouth rinse, antibiotics and non-surgical sequestrectomy and followed up for 1.5, 2, and 2 months; two patients became asymptomatic while one patient continued to have pain. These three reported patients with a history of ziv-aflibercept therapy and no reported use of other medications known to cause MRONJ developed exposed necrotic bone of the jaw. We believe that ziv-aflibercept is another medication that can potentially cause MRONJ probably through its anti-VEGF activity, similar to bevacizumab and sunitinib. PMID:28078129

  7. Spectral characteristics of speech with fixed jaw displacements

    NASA Astrophysics Data System (ADS)

    Solomon, Nancy P.; Makashay, Matthew J.; Munson, Benjamin

    2004-05-01

    During speech, movements of the mandible and the tongue are interdependent. For some research purposes, the mandible may be constrained to ensure independent tongue motion. To examine specific spectral characteristics of speech with different jaw positions, ten normal adults produced sentences with multiple instances of /t/, /s/, /squflg/, /i/, /ai/, and /squflgi/. Talkers produced stimuli with the jaw free to vary, and while gently biting on 2- and 5-mm bite blocks unilaterally. Spectral moments of /s/ and /squflg/ frication and /t/ bursts differed such that mean spectral energy decreased, and diffuseness and skewness increased with bite blocks. The specific size of the bite block had minimal effect on these results, which were most consistent for /s/. Formant analysis for the vocoids revealed lower F2 frequency in /i/ and at the end of the transition in /ai/ when bite blocks were used; F2 slope for diphthongs was not sensitive to differences in jaw position. Two potential explanations for these results involve the physical presence of the bite blocks in the lateral oral cavity, and the oromotor system's ability to compensate for fixed jaw displacements. [Work supported by NIDCD R03-DC06096.

  8. Jaw-Phonatory Coordination in Chronic Developmental Stuttering

    ERIC Educational Resources Information Center

    Loucks, Torrey M. J.; De Nil, Luc F.; Sasisekaran, Jayanthi

    2007-01-01

    A deficiency in sensorimotor integration in a person who stutters may be a factor in the pathophysiology of developmental stuttering. To test oral sensorimotor function in adults who stutter, we used a task that requires the coordination of a jaw-opening movement with phonation onset. The task was adapted from previous limb coordination studies,…

  9. Treatment of edentulism using Astra Tech implants and ball abutments to retain mandibular overdentures.

    PubMed

    Cooper, L F; Scurria, M S; Lang, L A; Guckes, A D; Moriarty, J D; Felton, D A

    1999-01-01

    The goal of this study was to provide evidence to support simplified treatment of mandibular edentulism using denture fabrication and implant placement to circumvent the need for second-stage surgeries or prosthodontic superstructures. A 5-year prospective clinical trial is reported, which involved treatment of mandibular edentulism using the single-stage surgical placement of a TiOblast microthreaded titanium screw implant with immediate replacement of a relieved mandibular overdenture and eventual retention of the overdenture with reduced ball abutments. Fifty-eight patients were treated; 116 implants were placed using a single-stage surgical approach, with a duplicate mandibular denture as the tomographic/surgical template. Mandibular dentures were relieved and relined with a tissue conditioning material and placed immediately after implant surgery. After 3 months, Conical Seal Design ball abutments were placed and attachments were secured in the overdentures by heat-polymerizing laboratory reline methods. Five of the 116 consecutively placed implants failed at 2 to 4 months, providing an immediate implant survival rate of 95.69% at the time of attachment connection. Pain and inflammation were not common to all failures, and infection was not reported in any of the 5 failures. The immediate placement of implants by a single-stage surgical procedure in the parasymphyseal region of the mandible, followed by placement of a relined mandibular denture, results in predictable and asymptomatic healing of implants that display the clinical and radiographic features of osseointegration. Encouraging results at the immediate observation period (attachment connection) must be tempered by the need for prudent and detailed clinical and radiologic evaluation over the 5-year trial period.

  10. A systematic review of biologic and technical complications with fixed implant rehabilitations for edentulous patients.

    PubMed

    Papaspyridakos, Panos; Chen, Chun-Jung; Chuang, Sung-Kiang; Weber, Hans-Peter; Gallucci, German O

    2012-01-01

    The purpose of this systematic review was to assess the incidence and types of biologic and technical complications associated with implant-supported fixed complete dental prostheses (IFCDPs) for edentulous patients. An electronic MEDLINE/PubMED search was conducted to identify randomized controlled clinical trials and prospective cohort studies with IFCDPs for edentulous patients. Reports with at least 5 years of follow-up after prosthesis insertion were selected. Pooled data were analyzed statistically, and the cumulative complication rates were calculated by meta-analysis and regression. Of a total of 281 one-piece IFCDPs (mean exposure time of 9.5 years) and 653 complication events, the complication rate was estimated at 24.6% per 100 restoration-years. The cumulative rates of "prosthesis free of complications" after 5 and 10 years were 29.3% and 8.6%, respectively. The most common implantrelated biologic complication was peri-implant bone loss (> 2 mm), at rates of 20.1% after 5 years and 40.3% after 10 years. The most frequent implant-related technical complication was screw fracture, yielding a 5-year complication rate of 10.4% and a 10-year rate of 20.8%. The most frequent prosthesis-related biologic complication was hypertrophy or hyperplasia of tissue around the IFCDPs (13.0% and 26.0% after 5 and 10 years, respectively). The most common prosthesis-related technical complication reported with IFCDPs was chipping or fracture of the veneering material (33.3% at 5 years and 66.6% at 10 years). Biologic and technical complications after the placement of IFCDPs occur continuously over time as a result of fatigue and stress. These events may not lead to implant/prosthetic failures, but they are significant in relation to the amount of repair and maintenance needed, time, and cost to both the clinician and patient.

  11. An economic evaluation of implant treatment in edentulous patients-preliminary results.

    PubMed

    Zitzmann, Nicola U; Sendi, Pedram; Marinello, Carlo P

    2005-01-01

    Edentulous patients with denture problems benefit from implant treatment with overdenture prostheses. The aim of this prospective study was to investigate a method of analyzing cost effectiveness in dentistry. As an example, overdenture treatment with two or four implants was compared to the conventional complete denture (CD). In a self-selected trial, 20 patients each were treated with implant-retained overdentures (two implants, IRET), implant-supported overdentures (four implants, ISUP), or CDs (control group) in the edentulous mandible. A cost-effectiveness analysis was performed from the patient's perspective, with a time horizon of 6 months. Direct health-care costs were calculated in Swiss Francs (in 2000), and effects were defined as improvements in perceived chewing ability compared with the baseline value before treatment (measured on a VAS). Point estimates for mean incremental cost-effectiveness ratios were complemented with cost-effectiveness acceptability curves to account for uncertainties associated with costs and effects. Mean incremental costs were CHF 4,329 (IRET-CD), CHF 13,360 (ISUP-CD), and CHF 9,031 (ISUP-IRET); these cost differences were all statistically significant. The mean incremental effects at 6 months were 19% (IRET-CD), 23% (ISUP-CD), and 4% (ISUP-IRET). Incremental cost-effectiveness ratios were CHF 228 (IRET-CD), CHF 581 (ISUP-CD), and CHF 2,258 (IRET-ISUP) per percentage increase in chewing ability. From an economic point of view, IRETs were more attractive than ISUPs. The latter were associated with a statistically significant improvement in perceived chewing ability compared to CDs, but at substantially higher costs.

  12. Success rates of microimplants in edentulous patients with residual ridge resorption.

    PubMed

    Morneburg, Thomas R; Pröschel, Peter A

    2008-01-01

    Restorative therapy of edentulous mandibles with residual ridge resorption is still a great challenge. Even though implant-supported stabilization of dentures has proved to be of value in these cases, treatment is sometimes problematic, not only due to narrow width of the denture-bearing areas but also because elderly patients are often averse to surgery. Implants with a normal length but a reduced diameter might facilitate therapy in patients with implant-supported dentures. The aim of the present study was to evaluate the clinical success of implants with a small diameter. In a prospective study, patients were provided with 2 implants 2.5 mm in diameter (MicroPlant; Brasseler, Lemgo, Germany) in a 2-stage procedure in the intraforaminal area of the edentulous mandible. Subsequently, the patients were monitored in periodic recalls. Periotest value, Gingival Index, and attachment level were monitored at these recall evaluations. Peri-implant bone loss was measured using panoramic radiographs. Patients rated the functionality of their denture using questionnaires administered before and after treatment. Sixty-seven patients were monitored during an average observation time of 6 years (SD 2.7). The cumulative survival rate of the implants was 95.5%. Clinical and radiographic parameters yielded results comparable to those of implants with a larger diameter. The questionnaire revealed sharp and significant improvement in denture retention and chewing ability after denture stabilization with the implants. The clinical data and the results of the questionnaire clearly indicated that the patients were satisfied with the concept of stabilization of complete mandibular dentures with small-diameter implants.

  13. Effects of Salivary Oxidative Markers on Edentulous Patients’ Satisfaction with Prosthetic Denture Treatments: A Pilot Study

    PubMed Central

    Feng, Sheng-Wei; Miao, Nae-Fang; Lin, Pei-Huan; Lin, Che-Tong; Tsai, Shin-Han; Huang, Yung-Kai

    2016-01-01

    Objectives The purpose of this study was to assess relationships among periodontal conditions, salivary antioxidant levels, and patients’ satisfaction with their prostheses. Methods This study was conducted at the Division of Prosthodontics, Department of Dentistry, Taipei Medical University Hospital. The periodontal condition of patients was based on an assessment of the plaque index (PI) and gingival index (GI). The pH value, flow rate, and buffer capacity of the saliva were estimated. The salivary total antioxidant status (TAS) and superoxide dismutase (SOD) level were also determined. Patients’ satisfaction with prosthetic treatments was evaluated using the Chinese version of the short-form Oral Health Impact Profile (OHIP-14C). A multivariate regression model was used to determine whether patients’ satisfaction with prosthetic treatment was affected by their oral health status. Results In total, 35 edentulous patients were recruited. In the Spearman correlation analysis, salivary pH (r = -0.36, p = 0.03) and the buffer ability (r = -0.48, p<0.01) were associated with OHIP-14C scores. In the multivariate analysis, patients who had a higher GI also had a higher score of physical disabilities (β = 1.38, p = 0.04). Levels of SOD increased with the scores of psychological discomfort (β = 0.33 U/g protein, p = 0.04). Conclusions This study suggested that both the GI and SOD levels were associated with patients’ satisfaction with prosthetic treatments. To the best of our knowledge, this is the first study to elucidate the relationship between OHIP scores and salivary oxidative markers in edentulous patients. PMID:26986841

  14. Distal extension mandibular removable partial denture with implant support

    PubMed Central

    Bural, Canan; Buzbas, Begum; Ozatik, Sebnem; Bayraktar, Gulsen; Emes, Yusuf

    2016-01-01

    This case report describes the fabrication of a distal extension removable partial denture (RPD) of a 65-year-old man with implant support. Loss of fibroelasticity of the peripheral tissues and reduced mandibular vestibular sulcular depth due to a previous surgical resection and radiotherapy at the right side were the main clinical factors that created difficulty for denture retention and stability. The fabrication of a mandibular RPD supported by anterior teeth and two bilaterally placed implants in the molar area to convert from Kennedy Class 1 design to Kennedy Class 3 implant-bounded RPD is reported. Retention and stability of the denture were improved with implant support on the distal extension site of the RPD. The common clinical problems about distally extended RPDs are lack of retention and stability due to the movement around the rotational axis. Dental implant placement to the distal edentulous site minimizes the potential dislodgement of the RPD is popular. Implant-supported RPD can be suggested as an advantageous and cost-effective treatment option for the partially edentulous patients. PMID:28042277

  15. Building Finite Element Models to Investigate Zebrafish Jaw Biomechanics

    PubMed Central

    Brunt, Lucy H.; Roddy, Karen A.; Rayfield, Emily J.; Hammond, Chrissy L.

    2016-01-01

    Skeletal morphogenesis occurs through tightly regulated cell behaviors during development; many cell types alter their behavior in response to mechanical strain. Skeletal joints are subjected to dynamic mechanical loading. Finite element analysis (FEA) is a computational method, frequently used in engineering that can predict how a material or structure will respond to mechanical input. By dividing a whole system (in this case the zebrafish jaw skeleton) into a mesh of smaller 'finite elements', FEA can be used to calculate the mechanical response of the structure to external loads. The results can be visualized in many ways including as a 'heat map' showing the position of maximum and minimum principal strains (a positive principal strain indicates tension while a negative indicates compression. The maximum and minimum refer the largest and smallest strain). These can be used to identify which regions of the jaw and therefore which cells are likely to be under particularly high tensional or compressional loads during jaw movement and can therefore be used to identify relationships between mechanical strain and cell behavior. This protocol describes the steps to generate Finite Element models from confocal image data on the musculoskeletal system, using the zebrafish lower jaw as a practical example. The protocol leads the reader through a series of steps: 1) staining of the musculoskeletal components, 2) imaging the musculoskeletal components, 3) building a 3 dimensional (3D) surface, 4) generating a mesh of Finite Elements, 5) solving the FEA and finally 6) validating the results by comparison to real displacements seen in movements of the fish jaw. PMID:28060270

  16. Dynamic Jaws and Dynamic Couch in Helical Tomotherapy

    SciTech Connect

    Sterzing, Florian; Uhl, Matthias; Hauswald, Henrik; Schubert, Kai; Sroka-Perez, Gabriele; Chen Yu; Lu Weiguo; Mackie, Rock; Debus, Juergen; Herfarth, Klaus; Oliveira, Gustavo

    2010-03-15

    Purpose: To investigate the next generation of helical tomotherapy delivery with dynamic jaw and dynamic couch movements. Methods and Materials: The new technique of dynamic jaw and dynamic couch movements is described, and a comparative planning study is performed. Ten nasopharyngeal cancer patients with skull base infiltration were chosen for this comparison of longitudinal dose profiles using regular tomotherapy delivery, running-start-stop treatment, and dynamic jaw and dynamic couch delivery. A multifocal simultaneous integrated boost concept was used (70.4Gy to the primary tumor and involved lymph nodes; 57.4Gy to the bilateral cervical lymphatic drainage pathways, 32 fractions). Target coverage, conformity, homogeneity, sparing of organs at risk, integral dose, and radiation delivery time were evaluated. Results: Mean parotid dose for all different deliveries was between 24.8 and 26.1Gy, without significant differences. The mean integral dose was lowered by 6.3% by using the dynamic technique, in comparison with a 2.5-cm-field width for regular delivery and 16.7% with 5-cm-field width for regular delivery. Dynamic jaw and couch movements reduced the calculated radiation time by 66% of the time required with regular 2.5-cm-field width delivery (199 sec vs. 595 sec, p < 0.001). Conclusions: The current delivery mode of helical tomotherapy produces dose distributions with conformal avoidance of parotid glands, brain stem, and spinal cord. The new technology with dynamic jaw and couch movements improves the plan quality by reducing the dose penumbra and thereby reducing the integral dose. In addition, radiation time is reduced by 66% of the regular delivery time.

  17. The adaptive response of jaw muscles to varying functional demands.

    PubMed

    Grünheid, Thorsten; Langenbach, Geerling E J; Korfage, Joannes A M; Zentner, Andrej; van Eijden, Theo M G J

    2009-12-01

    Jaw muscles are versatile entities that are able to adapt their anatomical characteristics, such as size, cross-sectional area, and fibre properties, to altered functional demands. The dynamic nature of muscle fibres allows them to change their phenotype to optimize the required contractile function while minimizing energy use. Changes in these anatomical parameters are associated with changes in neuromuscular activity as the pattern of muscle activation by the central nervous system plays an important role in the modulation of muscle properties. This review summarizes the adaptive response of jaw muscles to various stimuli or perturbations in the orofacial system and addresses general changes in muscles as they adapt, specific adaptive changes in jaw muscles under various physiologic and pathologic conditions, and their adaptive response to non-surgical and surgical therapeutic interventions. Although the jaw muscles are used concertedly in the masticatory system, their adaptive changes are not always uniform and vary with the nature, intensity, and duration of the stimulus. In general, stretch, increases neuromuscular activity, and resistance training result in hypertrophy, elicits increases in mitochondrial content and cross-sectional area of the fibres, and may change the fibre-type composition of the muscle towards a larger percentage of slow-type fibres. In contrast, changes in the opposite direction occur when neuromuscular activity is reduced, the muscle is immobilized in a shortened position, or paralysed. The broad range of stimuli that affect the properties of jaw muscles might help explain the large variability in the anatomical and physiological characteristics found among individuals, muscles, and muscle portions.

  18. Full mouth rehabilitation of destroyed dentition with rotational path removable partial denture: a case report.

    PubMed

    Kim, Moon-Hyoung; Heo, Seong-Joo; Kim, Seong-Kyun; Koak, Jai-Young

    2010-06-01

    Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure.

  19. Full mouth rehabilitation of destroyed dentition with rotational path removable partial denture: a case report

    PubMed Central

    Kim, Moon-Hyoung; Heo, Seong-Joo; Kim, Seong-Kyun

    2010-01-01

    BACKGROUND Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. CASE DESCRIPTION A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. CLINICAL IMPLICATION The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure. PMID:21165187

  20. Jaw-muscle fiber architecture in tufted capuchins favors generating relatively large muscle forces without compromising jaw gape.

    PubMed

    Taylor, Andrea B; Vinyard, Christopher J

    2009-12-01

    Tufted capuchins (sensu lato) are renowned for their dietary flexibility and capacity to exploit hard and tough objects. Cebus apella differs from other capuchins in displaying a suite of craniodental features that have been functionally and adaptively linked to their feeding behavior, particularly the generation and dissipation of relatively large jaw forces. We compared fiber architecture of the masseter and temporalis muscles between C. apella (n=12) and two "untufted" capuchins (C. capucinus, n=3; C. albifrons, n=5). These three species share broadly similar diets, but tufted capuchins occasionally exploit mechanically challenging tissues. We tested the hypothesis that tufted capuchins exhibit architectural properties of their jaw muscles that facilitate relatively large forces including relatively greater physiologic cross-sectional areas (PCSA), more pinnate fibers, and lower ratios of mass to tetanic tension (Mass/P(0)). Results show some evidence supporting these predictions, as C. apella has relatively greater superficial masseter and temporalis PCSAs, significantly so only for the temporalis following Bonferroni adjustment. Capuchins did not differ in pinnation angle or Mass/P(0). As an architectural trade-off between maximizing muscle force and muscle excursion/contraction velocity, we also tested the hypothesis that C. apella exhibits relatively shorter muscle fibers. Contrary to our prediction, there are no significant differences in relative fiber lengths between tufted and untufted capuchins. Therefore, we attribute the relatively greater PCSAs in tufted capuchins primarily to their larger muscle masses. These findings suggest that relatively large jaw-muscle PCSAs can be added to the suite of masticatory features that have been functionally linked to the exploitation of a more resistant diet by C. apella. By enlarging jaw-muscle mass to increase PCSA, rather than reducing fiber lengths and increasing pinnation, tufted capuchins appear to have

  1. Jaw-muscle fiber architecture in tufted capuchins favors generating relatively large muscle forces without compromising jaw gape

    PubMed Central

    Taylor, Andrea B.; Vinyard, Christopher J.

    2009-01-01

    Cebus apella is renowned for its dietary flexibility and capacity to exploit hard and tough objects. Cebus apella differs from other capuchins in displaying a suite of craniodental features that have been functionally and adaptively linked to their feeding behavior, particularly the generation and dissipation of relatively large jaw forces. We compared fiber architecture of the masseter and temporalis muscles between the tufted capuchin (C. apella; n = 12 ) and two “untufted” capuchins (C. capuchinus, n = 3; C. albifrons, n = 5). These three species share broadly similar diets, but tufted capuchins occasionally exploit mechanically challenging tissues. We tested the hypothesis that C. apella exhibits architectural properties of their jaw muscles that facilitate relatively large forces, including relatively greater physiologic cross-sectional areas (PCSA), more pinnate fibers, and lower ratios of mass to tetanic tension (Mass/P0). Results show some evidence supporting these predictions, as C. apella has relatively greater superficial masseter, whole masseter, and temporalis PCSAs, significantly so only for the temporalis following Bonferroni adjustment. Capuchins did not differ in pinnation angle or Mass/P0. As an architectural trade-off between maximizing muscle force and muscle excursion/contraction velocity, we also tested the hypothesis that C. apella exhibits relatively shorter muscle fibers. Contrary to our prediction, there are no significant differences in relative fiber lengths between tufted and untufted capuchins. Therefore, we attribute the relatively greater PCSAs in C. apella primarily to their larger muscle masses. These findings suggest that relatively large jaw-muscle PCSAs can be added to the suite of masticatory features that have been functionally linked to the exploitation of a more resistant diet by C. apella. By enlarging jaw-muscle mass to increase PCSA, rather than reducing fiber lengths and increasing pinnation, tufted capuchins appear

  2. Apodemes associated with limbs support serial homology of claws and jaws in Onychophora (velvet worms).

    PubMed

    de Sena Oliveira, Ivo; Mayer, Georg

    2013-10-01

    Although the onychophoran jaw blades are believed to be derivatives of foot claws, serial homology of these structures has not been demonstrated. To shed light on the evolutionary origin of the onychophoran jaws, we searched for morphological landmarks and compared the internal and external anatomy of jaws and distal leg portions in representatives of the two major onychophoran subgroups, the Peripatidae and Peripatopsidae. Our data revealed hitherto unknown structures associated with the onychophoran limbs, such as a soft diastemal membrane separating the anterior and posterior portions of the inner jaw blade (present only in Peripatidae), apodemes associated with feet, an eversible dorsal sac at the basis of each foot claw, and a specific arrangement of musculature associated with the sclerotised claws, jaws and their apodemes. Specific correspondences in structure and position of apodemes support serial homology of claws and jaws, suggesting that the onychophoran jaw evolved from the distal portion rather than the entire limb in the last common ancestor of Onychophora.

  3. Partial Tonsillectomy.

    PubMed

    Wong, Kevin; Levi, Jessica R

    2017-03-01

    Evaluate the content and readability of health information regarding partial tonsillectomy. A web search was performed using the term partial tonsillectomy in Google, Yahoo!, and Bing. The first 50 websites from each search were evaluated using HONcode standards for quality and content. Readability was assessed using the Flesch-Kincaid Grade Level (FKGL), Flesch Reading Ease, Gunning-Fog Index, Coleman-Liau Index, Automated Readability Index, and SMOG score. The Freeman-Halton extension of Fisher's exact test was used to compare categorical differences between engines. Less than half of the websites mentioned patient eligibility criteria (43.3%), referenced peer-reviewed literature (43.3%), or provided a procedure description (46.7%). Twenty-two websites (14.7%) were unrelated to partial tonsillectomy, and over half contained advertisements (52%). These finding were consistent across search engines and search terms. The mean FKGL was 11.6 ± 0.11, Gunning-Fog Index was 15.1 ± 0.13, Coleman-Liau Index was 14.6 ± 0.11, ARI was 12.9 ± 0.13, and SMOG grade was 14.0 ± 0.1. All readability levels exceeded the abilities of the average American adult. Current online information regarding partial tonsillectomy may not provide adequate information and may be written at a level too difficult for the average adult reader.

  4. Relevance of Variations in the Opposing Dentition for the Functionality of Fixed and Removable Partial Dentures: A Systematic Review

    PubMed Central

    Pommer, Bernhard; Krainhöfner, Martin; Watzek, Georg; Tepper, Gabor; Dintsios, Charalabos-Markos

    2012-01-01

    The aim of this systematic review was to evaluate the functionality of fixed and removable partial dentures as test interventions in relation to variations in the opposing dentition and their prosthetic restoration. The abstracts identified in the respective databases were screened independently by two investigators. RCTs and uncontrolled studies were considered, provided the patients were included consecutively and the confounding variables were adequately monitored. Seventeen papers were included. The study and publication quality was assessed using a “biometric quality” tool showing an overall poor quality. The reported outcomes, such as survival rates, were in each case obtained from a single study. Two possible trends could be deduced for the endpoint longevity: (a) the first trend in favor of removable partial dentures, compared to fixed partial dentures, with a fully edentulous opposing arch fitted with a removable prosthesis; (b) the second trend in favor of implant-supported partial dentures, compared to conventionally fixed partial dentures, with natural opposing dentition or with a removable partial denture in the opposing arch. No evidence could be generated as to whether, and if so how, variations in the opposing dentition have a bearing on the decision to fit a partially edentulous arch with a fixed or removable partial denture. PMID:23193407

  5. Prevalence of Loss of All Teeth (Edentulism) and Associated Factors in Older Adults in China, Ghana, India, Mexico, Russia and South Africa †

    PubMed Central

    Peltzer, Karl; Hewlett, Sandra; Yawson, Alfred E.; Moynihan, Paula; Preet, Raman; Wu, Fan; Guo, Godfrey; Arokiasamy, Perianayagam; Snodgrass, James J.; Chatterji, Somnath; Engelstad, Mark E.; Kowal, Paul

    2014-01-01

    Little information exists about the loss of all one’s teeth (edentulism) among older adults in low- and middle-income countries. This study examines the prevalence of edentulism and associated factors among older adults in a cross-sectional study across six such countries. Data from the World Health Organization (WHO’s) Study on global AGEing and adult health (SAGE) Wave 1 was used for this study with adults aged 50-plus from China (N = 13,367), Ghana (N = 4724), India (N = 7150), Mexico (N = 2315), Russian Federation (N = 3938) and South Africa (N = 3840). Multivariate regression was used to assess predictors of edentulism. The overall prevalence of edentulism was 11.7% in the six countries, with India, Mexico, and Russia has higher prevalence rates (16.3%–21.7%) than China, Ghana, and South Africa (3.0%–9.0%). In multivariate logistic analysis sociodemographic factors (older age, lower education), chronic conditions (arthritis, asthma), health risk behaviour (former daily tobacco use, inadequate fruits and vegetable consumption) and other health related variables (functional disability and low social cohesion) were associated with edentulism. The national estimates and identified factors associated with edentulism among older adults across the six countries helps to identify areas for further exploration and targets for intervention. PMID:25361046

  6. Factors that dentists use to decide whether or not to render a patient edentulous. Part 2. An investigation using a postal questionnaire sent to dentists in East lancashire.

    PubMed

    Pearce, Mark; Gedling, Catherine; Whittle, Gary; Robinson, Janet; Whitehead, Hilary

    2011-01-01

    To investigate the factors that dentists use to decide whether or not to make a patient edentulous. A previous qualitative investigation identified factors that dentists would consider when making a patient edentulous. Using this information, a questionnaire was created and sent to all dentists practising in East Lancashire, asking them whether these factors would make them more or less likely to extract all remaining teeth for a patient. 123 usable questionnaires were returned from 187 dentists, a response rate of 67%. Dentists felt that clinical factors such as poor periodontal health and active decay were more likely to make them extract all remaining teeth. They were also concerned about retention and were keen to retain strategic teeth. Apart from their acknowledgment of the need to comply with the patient's wish to keep his or her teeth, the dentists had a neutral opinion of other factors such as poor health or their personal attitude to treatment. On average, respondents were rendering just over three patients per year edentulous. In this group of dentists, the key clinical factors that were considered when they decided whether or not to render a patient edentulous were periodontal disease, caries, and the attitude of the patient to tooth loss. Relatively few patients were rendered edentulous each year and if this pattern is common elsewhere in the United Kingdom, it may lead to a lack of skills within the dental workforce in managing patients' transition from dentate to edentulous.

  7. Analysis of the blood supply to the post-fracture edentulous mandible: study by colour Doppler sonography.

    PubMed

    Mancini, Júlio Cezar M A; Garcia, Márcio Ricardo Taveira; de Oliveira, Ilka Regina Souza; de Freitas, Ronaldo Rodrigues; Luz, João Gualberto C

    2016-12-01

    This study assessed the arterial blood supply to the mandible of edentulous patients treated for mandibular fractures using colour Doppler ultrasound. The blood supply of edentulous patients surgically treated for mandibular fractures (group A) and edentulous fracture-free individuals (group B) was assessed. Only the fractured sides were evaluated in the first group (N = 17), whereas each side was evaluated in the second group (N = 20). The arterial flow of six sites was assessed. The systolic-peak maximum velocity (SPV), final diastolic velocity (FDV), resistive index (RI), pulsatility index (PI), acceleration and flow direction of each artery were obtained. Additionally, the presence of local vascular obstructive factors was evaluated. The differences between groups were analysed using the Kruskal-Wallis test, which was complemented by the Mann-Whitney test, for correlations between the degree of alveolar atrophy and the study factors (p < 0.050). There was a significant decrease in the flow of certain arteries, especially the submental (SPV, p = 0.007, PI, p = 0.022, and acceleration, p = 0.015), in the fracture group. The facial artery in both groups showed lower values related to local obstructive factors (SPV, p = 0.001, FDV, p = 0.040, and PI, p = 0.030). The submental artery flow was higher (SPV, p = 0.006, and FDV, p = 0.009) in non-atrophic individuals. There was a decreased flow mainly in the submental artery, but there were no cases of major vascular injury in edentulous patients treated for mandibular fractures.

  8. Removable Partial Denture Supported by Implants with Prefabricated Telescopic Abutments - A Case Report

    PubMed Central

    Sehgal, Komal

    2014-01-01

    Implants have been designed to rehabilitate edentulous patients with fixed prosthesis or implant supported overdentures. Implant-supported single crowns and fixed partial dentures have become successful treatment alternatives to removable and fixed partial dentures. However, it is common to have clinical situations which make it impossible to use conventional as well as implant supported fixed partial dentures. The implant supported removable partial dentures can be a treatment modality that offers the multitude of benefits of implant-based therapy—biologic, biomechanical, social, and psychological to such patients. The aim of this article is to present a case report describing the fabrication and advantages of removable partial denture supported by teeth and implants for a patient with long edentulous span. The patient was satisfied with his dentures in terms of function and aesthetics. Regular follow-up visits over a period of three years revealed that the periodontal condition of remaining natural dentition and peri-implant conditions were stable. There was no evidence of excessive residual ridge resorption or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs. PMID:25121066

  9. Multiple Compond Odontomas in the Jaws: A Rare Case Report

    PubMed Central

    Sahni, Priya; Pereira, Treville; Zingade, Jyoti

    2015-01-01

    Odontomas are tumours of odontogenic origin. In these tumours both the epithelial and mesenchymal cells undergo differentiation to form enamel and dentin with variable amounts of cementum and pulp tissue. The odontomas represent a hamartoma rather than a neoplasm. When the enamel and dentin are laid down in an organized manner it is termed as a compound odontoma wherein the tumour forms a collection of small structures resembling teeth. On the other hand, an irregular mass with no similarity to teeth is termed as a complex odontoma. There are cases of extensive and multiple compound odontomas which have been identified in either of the jaws. The present case is rare with multiple compound odontomas involving both the jaws of 45-year-old male patient. A review of seven such cases reported so far has been presented. PMID:26816995

  10. The origin and early phylogenetic history of jawed vertebrates

    PubMed Central

    Brazeau, Martin D.; Friedman, Matt

    2015-01-01

    The focus of study for nearly two centuries1, fossils of early gnathostomes—or jawed vertebrates—yield key clues about the evolutionary assembly of the bodyplan common to the group, as well the divergence of the two living gnathostome lineages: the cartilaginous and bony fishes2,3. A series of remarkable new palaeontological discoveries4-10, analytical advances and innovative reinterpretations of old fossils11-14 have fundamentally altered a decades-old consensus on the relationships of extinct gnathostomes15,16, delivering a new evolutionary framework3,6,10-14 for exploring major questions which remain unanswered, including the origin of jaws17-19. PMID:25903631

  11. Jaw, blink and corneal reflex latencies in multiple sclerosis.

    PubMed Central

    Sanders, E A; Ongerboer de Visser, B W; Barendswaard, E C; Arts, R J

    1985-01-01

    Jaw, blink and corneal reflexes, which all involve the trigeminal system, were recorded in 54 patients with multiple sclerosis; thirty-seven of these patients were classified as having definite multiple sclerosis and 17 as indefinite multiple sclerosis, according to Schumacher's criteria. The jaw reflex was abnormal less frequently than either of the other two reflexes, but in four cases it was the only abnormal reflex found. Testing a combination of two or three trigeminal reflexes did not yield a higher incidence of abnormalities than testing the blink or corneal reflex alone. Nine patients showed abnormal reflexes which were unexpected on the basis of clinical symptoms. The combined recordings demonstrate at least one abnormal reflex in 74% of the patients. The various types of reflex abnormalities reflect major damage to different parts of the trigeminal system and may therefore make an important contribution to the diagnosis of multiple sclerosis. PMID:4087004

  12. Double lead spiral platen parallel jaw end effector

    NASA Technical Reports Server (NTRS)

    Beals, David C.

    1989-01-01

    The double lead spiral platen parallel jaw end effector is an extremely powerful, compact, and highly controllable end effector that represents a significant improvement in gripping force and efficiency over the LaRC Puma (LP) end effector. The spiral end effector is very simple in its design and has relatively few parts. The jaw openings are highly predictable and linear, making it an ideal candidate for remote control. The finger speed is within acceptable working limits and can be modified to meet the user needs; for instance, greater finger speed could be obtained by increasing the pitch of the spiral. The force relaxation is comparable to the other tested units. Optimization of the end effector design would involve a compromise of force and speed for a given application.

  13. Sunitinib related osteonecrosis of jaw: a case report.

    PubMed

    Fleissig, Yoram; Regev, Eran; Lehman, Hadas

    2012-03-01

    A 58-year-old woman presented to the Oral and Maxillofacial Surgery Clinic experiencing severe limited mouth opening and exposed bone in the socket of the right mandibular third molar 8 months following the extraction of the tooth. The patient had been treated during the year before her presentation with sunitinib, an antiangiogenic drug, for renal cell carcinoma. The clinical, radiographic, and histologic picture of a chronic nonhealing extraction socket was consistent with osteonecrosis of the jaw (ONJ), although she had never been treated with bisphosphonates or corticosteroids. The treatment with sunitinib was discontinued and the patient was treated with antibiotics and physiotherapy for 12 weeks with complete recovery. Sunitinib may cause osteonecrosis of the jaw after oral surgical interventions with no previous exposure to bisphosphonates. The pathogenesis may be related to its antiangiogenic mechanism and impaired wound healing. Full recovery may require long-term cessation of the insulting drug combined with prolonged antibiotic treatment.

  14. Reduction of jaw opening (trismus) in giant cell arteritis

    PubMed Central

    Nir-Paz, R; Gross, A; Chajek-Shaul, T

    2002-01-01

    Methods: the prevalence of such symptoms in patients with GCA was evaluated by performing a retrospective analysis of all patients with GCA and polymyalgia rheumatica who were diagnosed during admission to Hadassah University Hospital. Ten patients reported previously in the literature were also evaluated. Results: Six patients out of 88 (6.8%) had complaints of reduction in jaw opening. These six patients seemed to have a much more abrupt onset of disease with shorter duration until diagnosis, higher prevalence of eye involvement (50% v 27%), and a higher rate of positive pathology (100%). Conclusions: Reduction in jaw opening in the appropriate setting may indicate the presence of GCA. This sign should not be overlooked in the presence of the claudication sign as it seems to reflect more severe GCA disease. PMID:12176811

  15. The earliest herbivorous marine reptile and its remarkable jaw apparatus

    PubMed Central

    Chun, Li; Rieppel, Olivier; Long, Cheng; Fraser, Nicholas C.

    2016-01-01

    Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles. PMID:27386529

  16. Modeling of temporomandibular joint function using MRI and jaw-tracking technologies--mechanics.

    PubMed

    Gallo, Luigi M

    2005-01-01

    The study of mechanics of the temporomandibular joint (TMJ) is important because its dysfunction and breakdown could be, at least partially, of mechanical origin. The incongruity of the articular surfaces of the TMJ is compensated by a fibrocartilaginous articular disc. Its dislocation and failure seem to be closely related to the development of osteoarthritis of the TMJ. The analysis of mandibular kinematics permits the detection and assessment of irregularities of TMJ function due to internal obstacles such as a displaced articular disc. Furthermore, the measurement of the dynamic relationship between the articular surfaces of the TMJ is useful to determine the strains undergone by the disc that if too high might compromise its integrity. The development of our research in TMJ mechanics has evolved from the acquisition of the traces of single mandibular points to an accurate and compact description of mandibular motion, in which the mechanical advantage of jaw muscles, and forces and torques acting on the jaw are considered as well. The combination of three-dimensional software models of TMJ anatomies obtained from MRI and jaw tracking with six degrees of freedom permits a subject-specific dynamic analysis of the intra-articular space, providing insight into individual disc deformation during function and TMJ loading. Studies performed with this system indicate that both TMJs are loaded during chewing, the balancing more so than the working joint. In fact, during chewing, the intra-articular distance is smaller for hard than for soft food, on closing than on opening, on the balancing than on the working side. This last finding is confirmed by static biting experiments, in which the condyle-fossa distance decreases more on the side contralateral to the bite force, depending on its magnitude. Also studies on the dynamics of compression areas indicate that plowing can occur through the disc during function, especially mediolaterally, due to stress field translation

  17. Period between completion of radiation therapy and prosthetic rehabilitation in edentulous patients: a retrospective study.

    PubMed

    Gerngross, Peter J; Martin, Charles D; Ball, John D; Engelmeier, Robert L; Gilbert, Harry D; Powers, John M; Narendran, Sena; Chambers, Mark S

    2005-06-01

    The primary purposes of this study were: (1) to describe the number and types of complications patients had before and after insertion of a removable prosthesis (i.e., denture) following radiation therapy to the head and neck and (2) to investigate whether the time between radiation therapy and denture insertion might contribute to those complications. This research evaluated edentulous patients and those who were rendered edentulous as a result of their cancer treatment. After obtaining institutional approval following HIPAA regulations, a total of 349 charts were identified: 152 patients from Houston Veterans Administration Medical Center (HVAMC) and 197 patients from M. D. Anderson Cancer Center (MDACC). A total of 190 patients met the inclusion criteria with data available for review. No significant differences were found in any of the comparisons made, except when comparing complications that occurred after the dentures were inserted and the amount of time it took for prosthetic rehabilitation. The majority of patients had no complications. The patients who received their dentures in 180 days or less had the same number of complications when compared with those patients who received their dentures in 181 to 365 days and those who had to wait longer than a year for prosthetic rehabilitation. Patients with more pre-insertion complications tended to have delayed prosthetic rehabilitation. Those patients who had complications both before and after denture insertion tended to have bilateral dosing of their radiation treatment. Patients who had received radiation therapy were 1.7 times more likely to have post-prosthesis insertion complications. The majority of patients who experienced complications before and after denture insertion had greater than 5000 cGy. The numbers of complications reviewed in this retrospective analysis were considerably fewer than the number expected. There appears to be no difference in the number of pre- and post-insertion complications

  18. Virtual implant planning in the edentulous maxilla: criteria for decision making of prosthesis design.

    PubMed

    Avrampou, Marianna; Mericske-Stern, Regina; Blatz, Markus B; Katsoulis, Joannis

    2013-08-01

    To evaluate prosthetic parameters in the edentulous anterior maxilla for decision making between fixed and removable implant prosthesis using virtual planning software. CT- or DVT-scans of 43 patients (mean age 62 ± 8 years) with an edentulous maxilla were analyzed with the NobelGuide software. Implants (≥3.5 mm diameter, ≥10 mm length) were virtually placed in the optimal three-dimensional prosthetic position of all maxillary front teeth. Anatomical and prosthetic landmarks, including the cervical crown point (C-Point), the acrylic flange border (F-Point), and the implant-platform buccal-end (I-Point) were defined in each middle section to determine four measuring parameters: (1) acrylic flange height (FLHeight), (2) mucosal coverage (MucCov), (3) crown-Implant distance (CID) and (4) buccal prosthesis profile (ProsthProfile). Based on these parameters, all patients were assigned to one of three classes: (A) MucCov ≤ 0 mm and ProsthProfile≥45(0) allowing for fixed prosthesis, (B) MucCov = 0-5 mm and/or ProsthProfile = 30(0) -45(0) probably allowing for fixed prosthesis, and (C) MucCov ≥ 5 mm and/or ProsthProfile ≤ 30(0) where removable prosthesis is favorable. Statistical analyses included descriptive methods and non-parametric tests. Mean values were for FLHeight 10.0 mm, MucCov 5.6 mm, CID 7.4 mm, and ProsthProfile 39.1(0) . Seventy percent of patients fulfilled class C criteria (removable), 21% class B (probably fixed), and 2% class A (fixed), while in 7% (three patients) bone volume was insufficient for implant planning. The proposed classification and virtual planning procedure simplify the decision-making process regarding type of prosthesis and increase predictability of esthetic treatment outcomes. It was demonstrated that in the majority of cases, the space between the prosthetic crown and implant platform had to be filled with prosthetic materials. © 2012 John Wiley & Sons A/S.

  19. Polygonal Area of Prosthesis Support with Straight and Tilted Dental Implants in Edentulous Maxillae.

    PubMed

    Wentaschek, Stefan; Lehmann, Karl Martin; Scheller, Herbert; Weibrich, Gernot; Behneke, Nikolaus

    2016-01-01

    The aim of this in vitro study was to assess the increase in the polygonal area of implant-retained prosthesis supports in edentulous maxillae with the use of tilted distal implants compared with the use of straight distal implants, using a variety of implant lengths. A total of 25 DICOM datasets of atrophic edentulous maxillae were provided. Bone augmentations in the molar region had to be avoided. Two straight reference implants were virtually inserted in the anterior region. Two additional implants were placed far distally on both sides (4 groups: [1] straight, 12-mm length; [2] straight, 10 mm; [3] straight, 8 mm; [4] tilted, 12-16 mm). The resulting implant-supported polygon was measured for each of the 4 groups using three-dimensional planning software. The mean sagittal depth of the supported polygon in Group 1 was 9.9 mm (standard deviation [SD] 4.4) on the right and 10.2 mm (SD 4.4) on the left, and it was 33.7 mm (SD 5.8) in width. For Group 2, the mean sagittal depth was 11.5 mm (SD 5.0) on the right and 11.9 mm (SD 4.7) on the left, and the width was 35.2 mm (SD 5.6). The measurements for Group 3 were 13.8 mm (SD 4.9) deep on the right, 13.8 mm (SD 5.1) deep on the left, and 37.0 mm (SD 5.4) in width. For Group 4, the depth was 15.8 mm (SD 4.9) on the right and 16.4 mm (SD 5.8) on the left, and the width was 39.0 mm (SD 5.1). The area of implant-retained prosthesis support can be enlarged by the use of tilted implants (12 to 16 mm in length, 42 to 45 degrees) compared to the use of straight 8-mm implants (resulting increase: about 15%).

  20. Description of the lower jaws of Baculites from the Upper Cretaceous U.S. Western Interior

    NASA Astrophysics Data System (ADS)

    Larson, Neal L.; Landman, Neil H.

    2017-03-01

    We report the discovery of lower jaws of Baculites (Ammonoidea) from the Upper Cretaceous U.S. Western Interior. In the lower Campanian Smoky Hill Chalk Member of the Niobrara Chalk of Kansas, most of the jaws occur as isolated elements. Based on their age, they probably belong to Baculites sp. (smooth). They conform to the description of rugaptychus, and are ornamented with coarse rugae on their ventral side. One specimen is preserved inside a small fecal pellet that was probably produced by a fish. Another specimen occurs inside in a crushed body chamber near the aperture and is probably in situ. Three small structures are present immediately behind the jaw and may represent the remains of the gills. In the lower Maastrichtian Pierre Shale of Wyoming, two specimens of Baculites grandis contain lower jaws inside their body chambers, and are probably in situ. In both specimens, the jaws are oriented at an acute angle to the long axis of the shell, with their anterior ends pointing toward the dorsum. One of the jaws is folded into a U-shape, which probably approximates the shape of the jaw during life. Based on the measurements of the jaws and the shape of the shell, the jaws could not have touched the sides of the shell even if they were splayed out, implying that they could not have effectively served as opercula. Instead, in combination with the upper jaws and radula, they constituted the buccal apparatus that collected and conveyed food to the esophagus.

  1. Electrophysiological analysis of rhythmic jaw movements in the freely moving mouse.

    PubMed

    Kobayashi, Masayuki; Masuda, Yuji; Fujimoto, Yoshiyuki; Matsuya, Tokuzo; Yamamura, Kensuke; Yamada, Yoshiaki; Maeda, Norihiko; Morimoto, Toshifumi

    2002-03-01

    Although rhythmic jaw movement in feeding has been studied in mammals, such as rats, rabbits and monkeys, the cellular and molecular mechanisms underlying it are not well understood. Transgenic and gene-targeting technologies enable direct control of the genetic makeup of the mouse, and have led to the development of a new category of reagents that have the potential to elucidate the cellular and molecular mechanisms of neural networks. The present study attempts to characterize rhythmic jaw movements in the mouse and to demonstrate its relevance to rhythmic jaw movements found in higher mammals using newly developed jaw-tracking systems and electromyograms of the masticatory muscles. The masticatory sequence of the mouse during feeding was classified into two stages, incision and chewing. Small and rapid (8 Hz) open-close jaw movements were observed during incision, while large and slow (5 Hz) open-close jaw movements were observed during chewing. Integrated electromyograms of the masseteric and digastric muscles were larger during chewing than those observed during incision. Licking behavior was associated with regular (8 Hz), small open-close jaw movements with smaller masseteric activity than those observed during mastication. Grooming showed variable patterns of jaw movement and electromyograms depending on the grooming site. These results suggest that there are neuronal mechanisms producing different frequencies of rhythmic jaw movements in the mouse, and we conclude that the mouse is useful for understanding rhythmic jaw movements in higher mammals.

  2. Gum chewing and jaw muscle fatigue and pains.

    PubMed

    Christensen, L V; Tran, K T; Mohamed, S E

    1996-06-01

    To study possible associations between gum chewing and fatigue and pains in the jaw muscles, eight healthy adults performed prolonged idling, prolonged unilateral chewing of gum, and brief vigorous clenching of the teeth (MVC). Through surface electromyography (EMG), the authors monitored the cumulative (microV.s) as well as the average rates (microV.s-1) of contractile activities in the right and left masseter muscles. During 10 min of idling there was an absence of muscle fatigue and muscle pains when the EMG rates of the right and left masseter muscles were 2% and 3%, respectively, of those required to elicit isometric muscle pains through MVC. During 10 min of right-sided gum chewing at a rate of 1.2 Hz, the majority of subjects (75%) experienced weak jaw muscle fatigue-not jaw muscle pains-when the EMG rates of the right and left masseter muscles were 38% and 19%, respectively, of those required to elicit isometric pains through MVC. In comparison with 10 min of idling, the weak muscle fatigue of 10 min of unilateral gum chewing appeared when the total contractile activities of the right and left masseter muscles were increased by 1664% and 519%, respectively. It seemed as if prolonged unilateral gum chewing and previous pain-releasing MVC caused some sensitization of muscle nociceptors which, in turn, aggravated subsequent isometric jaw muscle pains elicited through MVC. Even though the right masseter muscle was the most frequent site of clinical fatigue and pains, the authors found no evidence supporting the theoretical foundation of the myofascial pain/dysfunction syndrome.

  3. Pharmacologic modalities in the treatment of osteoradionecrosis of the jaw.

    PubMed

    McCaul, James Anthony

    2014-05-01

    Managing osteoradionecrosis (ORN) of the facial bones is a challenge in maxillofacial head and neck surgery. Changes in understanding of ORN of the jaws has led to new studies using novel therapeutic modalities to manage this disorder. These treatment regimens may allow medical management to replace major reconstructive surgery for some patients who have already undergone chemoradiotherapy or combined modality therapy for head and neck cancer.

  4. An Endocrine Jaw Lesion: Dentist Perspective in Diagnosis

    PubMed Central

    Kalapala, Lavanya; Babburi, Suresh; Venigalla, Aparna; Pinisetti, Soujanya; Ganipineni, Kiranmai

    2016-01-01

    Brown tumor is a rare nonneoplastic focal giant cell lesion that occurs in hyperparathyroidism patients with a prevalence rate of 0.1% in jaws. We report an extremely rare case of brown tumor in mandible of a 40-year-old female patient that presented as the first clinical manifestation of hyperparathyroidism. Dentist played a pivotal role in the present case by the early diagnosis of lesion and its intervention. PMID:27974979

  5. Bisphosphonates and jaw osteonecrosis in patients with advanced breast cancer.

    PubMed

    Sanna, G; Preda, L; Bruschini, R; Cossu Rocca, M; Ferretti, S; Adamoli, L; Verri, E; Franceschelli, L; Goldhirsch, A; Nolè, F

    2006-10-01

    In recent years, several cases of mandibular necrosis associated with long-term use of bisphosphonates have been reported. The estimated incidence varies from 1% to 4.6%. We conducted an observational study with the aim of determining the incidence of jaw osteonecrosis in advanced breast cancer patients with bone metastases under bisphosphonate treatment and to identify subjects at higher risk of developing this complication evaluating preclinical signs. We considered two groups of patients. All the patients complaining of odontostomatological symptoms underwent maxillary CT scan and maxillo-surgeon clinical examination. Asymptomatic patients were asked to perform a standard orthopantomography (OPT). From February 2005 to October 2005, we observed five patients with jaw bone necrosis (6%). Diagnosis was radiological and clinical. In two patients a confirmatory biopsy was performed. In the same time interval, OPTs were collected from 76 asymptomatic patients. Three OPTs revealed radiological features of suspicious mandibular necrosis. Maxillary CT scan confirmed the presence of an osteolityc area with signs of periosteal reaction. All the three patients were referred to maxillo-surgeon and two out of three patients underwent mandibular biopsy, but histopathological results were not conclusive. In our experience, the incidence of jaw bone necrosis in breast cancer patients seems to be higher than in other reports (6%). Radiological features of suspicious jaw necrosis were observed in three asymptomatic patients. We do not know how these findings should be considered. Anyway, standard OPT is a simple procedure, and may allow identification of periodontal conditions that in some way can predispose to the development of this uncommon event.

  6. Interactions between the jaw-opening reflex and mastication.

    PubMed

    Lund, J P; Rossignol, S; Murakami, T

    1981-07-01

    Electrical stimulation of the anterior hard palate or upper lip was used to evoke the jaw-opening reflex in rabbits lightly anesthetized with urethane. The amplitude of each excitatory response recorded in the digastric electromyogram during mastication was compared with the mean amplitude of 10 prior control responses. When weak stimuli were used, the mean amplitude of the reflex dropped markedly during mastication and was smallest when the digastric muscle was inactive (closing and occlusal phases of the masticatory cycle). As the stimulus strength was increased, the size of the response during closing rose progressively until it exceeded values obtained during the control period or the jaw-opening phase. In addition, strong stimuli altered the total cycle length and the duration and amplitude of muscle activity in a phase-dependent manner. Stimuli given during closing were particularly effective in causing inhibition of jaw-closing muscle activity and in reducing the velocity and amplitude of closure. It is concluded that the cyclical gain changes of the reflex response to noxious stimuli are controlled to a large extent by premotoneuronal mechanisms and that the overall effect on the masticatory cycle structure is phase dependent.

  7. Midsagittal jaw movements as a sleep/wake marker.

    PubMed

    Senny, Frédéric; Destiné, Jacques; Poirrier, Robert

    2009-02-01

    The seriousness of the Obstructive Sleep Apnea/Hypopnea Syndrome is measured by the apnea-hypopnea index (AHI), the number of sleep apneas and hypopneas over the total sleep time (TST). Cardiorespiratory signals are used to detect respiratory events while the TST is usually assessed by the analysis of electroencephalogram traces in polysomnography (PSG) or wrist actigraphy trace in portable monitoring. This paper presents a sleep/wake automatic detector that relies on a wavelet-based complexity measure of the midsagittal jaw movement signal and multilayer perceptrons. In all, 63 recordings were used to train and test the method, while 38 recordings constituted an independent evaluation set for which the sensitivity, the specificity, and the global agreement of sleep recognition, respectively, reached 85.1%, 76.4%, and 82.9%, compared with the PSG data. The AHI computed automatically and only from the jaw movement analysis was significantly improved (p < 0.0001) when considering this sleep/wake detector. Moreover, a sensitivity of 88.6% and a specificity of 83.6% were found for the diagnosis of the sleep apnea syndrome according to a threshold of 15. Thus, the jaw movement signal is reasonably accurate in separating sleep from wake, and, in addition to its ability to score respiratory events, is a valuable signal for portable monitoring.

  8. Bisphosphonates and osteonecrosis of the jaw--current thoughts.

    PubMed

    Arrain, Yazdana; Masud, Tahir

    2009-09-01

    Bisphosphonates are increasingly being used in a number of bone conditions, including osteoporosis and metastatic cancer. As a consequence, the reported cases of bisphosphonate-related osteonecrosis of the jaw (BONJ) have increased. BONJ remains rare in patients being treated for osteoporosis, but is commoner in cancer patients where the bisphosphonate doses are much higher and mode of delivery is intravenous. Recently, much more is known about classification and mode of action of the bisphosphonates. The potency of the various nitrogen-containing bisphosphonates is dependent on a number of factors including bone binding, zeta potential and inhibition of the enzyme farnesyl pyrophosphate synthase. There is current debate on why BONJ affects the jaw, particularly in relation to whether the jaw has high bone turnover or not. More is being learnt about the micro-organisms involved in the pathogenesis of BONJ and there is increasing evidence on the role of surgical treatment of this disabling condition. Dentists should be aware of the association of bisphosphonates and BONJ. This paper provides recent knowledge on bisphosphonate action, pathogenesis of BONJ and its treatment.

  9. Computer Simulation Methods for Crushing Process in an Jaw Crusher

    NASA Astrophysics Data System (ADS)

    Il'ich Beloglazov, Ilia; Andreevich Ikonnikov, Dmitrii

    2016-08-01

    One of the trends at modern mining enterprises is the application of combined systems for extraction and transportation of the rock mass. Given technology involves the use the conveyor lines as a continuous link of combined technology. The application of a conveyor transport provides significant reduction of costs for energy resources, increase in labor productivity and process automation. However, the use of a conveyor transport provides for certain requirements for the quality of transported material. The maximum size of the rock mass pieces is one of the basic parameters for it. The crushing plants applies as a coarse crushing followed by crushing the material to the maximum size of piece which possible to use for conveyor transport. It is often represented by jaw crushers. Modelling of crushing process in jaw crushers allows to maximally optimize workflow and increase efficiency of the equipment at the further transportation and processing of rocks. We studied the interaction between walls of the jaw crusher and bulk material by using discrete element method (DEM) in this paper. The article examines the process of modeling by stages. It includes design of the crusher construction in solid and surface modeling system. Modelling of the crushing process based on the experimental data received via the crushing unit BOYD. The process of destruction and particle size distribution in the study was done. Analysis of research results shows a comparability of actual experiment and modeling process.

  10. Osteosarcoma of the jaws: demographic and CT imaging features

    PubMed Central

    Wang, S; Shi, H; Yu, Q

    2012-01-01

    Objective The aim of this study was to evaluate the patient demographic and CT imaging findings of primary osteosarcoma of the jaws. Methods 88 primary osteosarcomas of the jaws histopathologically diagnosed during 1997–2007 were reviewed. 21 cases of CT images were reviewed. Results Of 88 patients, 51 (58%) had tumours in the mandible and 37 (42%) in the maxilla. The mean age was 37.8 years (range 9–80 years). The male-to-female ratio was 1.32:1. The mean age of patients with mandibular lesions was 41.04 years and in those with maxillary lesions it was 33.3 years. CT imaging findings were available in 21 patients. In the maxilla (n = 9), all tumours (100%) arose from the alveolar ridge. In the mandible (n = 12), most tumours (9 cases, 75%), arose from the ramus and/or condyle. All except two lesions had the epicentrum within the medullary cavity of the involved bone. The presence of periosteal reaction was demonstrated in 13 cases (62%). Soft-tissue extension was present in 18 lesions (86%), with calcification identified in 13 (72%). Conclusions This study provides age, sex distribution, location and CT imaging features of primary osteosarcoma of the jaws. PMID:22074870

  11. Bisphosphonate-induced osteonecrosis of the jaw: a medical enigma?

    PubMed

    Siddiqi, Allauddin; Payne, Alan G T; Zafar, Sobia

    2009-09-01

    Bisphosphonates are used for the standard of care of patients with skeletal metastases and hypocalcemia of malignancy. Bisphosphonate-induced osteonecrosis (BION) is a serious complication. Clinically, BION presents as an area of exposed alveolar bone that occurs spontaneously or becomes evident following an invasive surgical procedure such as extraction of a tooth, periodontal surgery, apicoectomy, or oral implant placement. The mechanism by which bisphosphonates cause osteonecrosis is uncertain. There are no controlled trials to show a direct cause-effect relationship between bisphosphonates and osteonecrosis of the jaw. Oral bisphosphonate-induced necrosis is a rare clinical entity, less frequent, less aggressive, more predictable, and more responsive to treatment than IV forms of bisphosphonate-related osteonecrosis of the jaw. However, there have been reports of this complication with the less potent oral forms of bisphosphonates (0.007% to 0.01%). The morbidity of osteonecrosis of the jaw induced by IV bisphosphonates is significant, so prevention should receive prime importance. Patients should receive prophylactic dental examinations, and any necessary dental treatment before starting bisphosphonate therapy. Good communication among dentists, oral surgeons, physicians, and oncologists is of vital importance in providing care of these patients.

  12. Scaling and Accommodation of Jaw Adductor Muscles in Canidae

    PubMed Central

    Kemp, Graham J.; Jeffery, Nathan

    2016-01-01

    ABSTRACT The masticatory apparatus amongst closely related carnivoran species raises intriguing questions about the interplay between allometry, function, and phylogeny in defining interspecific variations of cranial morphology. Here we describe the gross structure of the jaw adductor muscles of several species of canid, and then examine how the muscles are scaled across the range of body sizes, phylogenies, and trophic groups. We also consider how the muscles are accommodated on the skull, and how this is influenced by differences of endocranial size. Data were collected for a suite of morphological metrics, including body mass, endocranial volume, and muscle masses and we used geometric morphometric shape analysis to reveal associated form changes. We find that all jaw adductor muscles scale isometrically against body mass, regardless of phylogeny or trophic group, but that endocranial volume scales with negative allometry against body mass. These findings suggest that head shape is partly influenced by the need to house isometrically scaling muscles on a neurocranium scaling with negative allometry. Principal component analysis suggests that skull shape changes, such as the relatively wide zygomatic arches and large sagittal crests seen in species with higher body masses, allow the skull to accommodate a relative enlargement of the jaw adductors compared with the endocranium. Anat Rec, 299:951–966, 2016. © 2016 The Authors The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc. PMID:27103346

  13. Evolution of the vertebrate jaw from developmental perspectives.

    PubMed

    Kuratani, Shigeru

    2012-01-01

    Attainment of the biting jaw is regarded as one of the major novelties in the early history of vertebrates. Based on a comparison between lamprey and gnathostome embryos, evolutionary developmental studies have tried to explain this novelty as changes in the developmental patterning of the mandibular arch, the rostralmost pharyngeal arch, at the molecular and cellular levels. On the other hand, classical theories in the field of comparative morphology assumed the involvement of hypothetical premandibular arch(es) that ancestral animals would have possessed rostral to the mandibular arch, in the transition from agnathan to gnathostome states. These theories are highly biased toward the segmental scheme of the vertebrate head, and the concept of premandibular "arches" is no longer accepted by the current understanding. Instead, the premandibular domain has now become of interest in the understanding of cranial development, especially in its rostral part. As newer theories that consider involvement of the premandibular domain, the neoclassical and heterotopy theories are here compared from evolutionary developmental perspectives, in conjunction with the development of nasal and hypophyseal placodes, in the context of the evolutionary acquisition of the jaw. Given recent advances in understanding of the lamprey development, evolution of the Dlx code is also discussed together with the evolutionary scenario of jaw acquisition. © 2012 Wiley Periodicals, Inc.

  14. A comparison of cephalometric analyses for assessing sagittal jaw relationship.

    PubMed

    Gul-e-Erum; Fida, Mubassar

    2008-11-01

    To compare the seven methods of cephalometric analysis for assessing sagittal jaw relationship and to determine the level of agreement between them. Cross-sectional, analytical study. Dental Section, the Aga Khan University Hospital, Karachi, from January to December 2004. Seven methods, describing anteroposterior jaw relationships (A-B plane, ANB, Wits, AXB, AF-BF, FABA and Beta angle) were measured on the lateral cephalographs of 85 patients. Correlation analysis, using Cramer's V-test, was performed to determine the possible agreement between the pair of analyses. The mean age of the sample, comprising 35 males and 50 females was 15 years and 3 months. Statistically significant relationships were found among seven sagittal parameters with p-value < 0.001. Very strong correlation was found between AXB and AF-BF distance (r=0.924); and weak correlation between ANB and Beta angle (r=0.377). Wits appraisal showed the greatest coefficient of variability. Despite varying strengths of association, statistically significant correlations were found among seven methods for assessing sagittal jaw relationship. FABA and A-B plane may be used to predict the skeletal class in addition to the established ANB angle.

  15. Jaw lesions associated with impacted tooth: A radiographic diagnostic guide

    PubMed Central

    Mortazavi, Hamed

    2016-01-01

    This review article aimed to introduce a category of jaw lesions associated with impacted tooth. General search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks were used to find relevant studies using keywords such as "jaw lesion", "jaw disease", "impacted tooth", and "unerupted tooth". More than 250 articles were found, of which approximately 80 were broadly relevant to the topic. We ultimately included 47 articles that were closely related to the topic of interest. When the relevant data were compiled, the following 10 lesions were identified as having a relationship with impacted tooth: dentigerous cysts, calcifying odontogenic cysts, unicystic (mural) ameloblastomas, ameloblastomas, ameloblastic fibromas, adenomatoid odontogenic tumors, keratocystic odontogenic tumors, calcifying epithelial odontogenic tumors, ameloblastic fibro-odontomas, and odontomas. When clinicians encounter a lesion associated with an impacted tooth, they should first consider these entities in the differential diagnosis. This will help dental practitioners make more accurate diagnoses and develop better treatment plans based on patients' radiographs. PMID:27672610

  16. Immediate rehabilitation of completely edentulous arches with a four-implant prosthesis concept in difficult conditions: an open cohort study with a mean follow-up of 2 years.

    PubMed

    Malo, Paulo; Nobre, Miguel de Araújo; Lopes, Armando

    2012-01-01

    There is a growing pressure in implant dentistry to perform implant rehabilitations in difficult conditions, such as fresh extraction sockets, periodontally compromised sites, or sites with low bone density and quantity that imply a high likelihood of dehiscences or fenestrations. The aim of this study was to document complete rehabilitations in both jaws through the so-called All-on-Four concept (ie, four implants with the posterior implants placed at an angle) using immediate function implants inserted in "nonideal" conditions (eg, implants inserted with dehiscences or fenestrations, in periodontally compromised sites, or in fresh extraction sockets). This prospective cohort study included patients with immediately functioning implants placed in difficult conditions to support fixed full-arch maxillary and mandibular prostheses. One hundred forty-two patients received 227 implants. A total of seven implants failed in six patients (three implants in three patients in the maxilla and four implants in three patients in the mandible), for cumulative patient and implant survival rates of 96.2% and 97.7% for the maxilla and 94.7% and 94.8% for the mandible, respectively, after 2 years (Kaplan-Meier). The average (standard deviation) peri-implant bone resorption after 1 year and 3 years in the maxilla was 1.3 mm (0.4 mm) and 1.6 mm (0.4 mm), respectively; in the mandible, the average (standard deviation) peri-implant bone resorption at 1 year and 5 years was 1.4 mm (0.3 mm) and 1.7 mm (0.6 mm), respectively. The results support the conclusion that the four-implant ("All-on-Four") immediate-function concept in completely edentulous maxillae and mandibles using implants inserted in difficult conditions is a viable concept in the short term.

  17. Influences of differences in tray design and impression material on impression pressure at edentulous mandible.

    PubMed

    Inoue, Sayumi; Kawara, Misao; Iida, Takashi; Iwasaki, Masatoshi; Komiyama, Osamu

    2017-08-31

    The aim of this study was to examine the effects of tray design and impression material on impression pressure in a clinical simulation model of an edentulous mandible. Two types of polyvinylsiloxane elastomer, one type of polyether elastomer, and one type of alginate were used. The three tray types had no relief, 0.36 mm of relief, or 1.4 mm of relief, with or without escape holes. Impression pressure was measured at the median alveolar crest, the bilateral alveolar crests corresponding to molars, and the bilateral buccal shelves. Impression pressure significantly differed in relation to tray design and sensor position. In trays without escape holes, impression pressure was highest at the median alveolar crest and lowest at the buccal shelves, for all impression materials. However, impression material had no significant effects on impression pressure. Our results suggest that bite-pressure load on alveolar crests can be alleviated by making an impression with a tray that has relief and escape holes, while applying pressure to buccal shelves and almost no pressure to alveolar crests.

  18. Prosthodontic rehabilitation for edentulous patients with palatal defect: report of two cases.

    PubMed

    Lin, Fen-Huey; Wang, Tsung-Chih

    2011-02-01

    Cancer resection is the most common cause of acquired palatal defects, whereas cleft palate is the main cause of congenital defects. Palatal defect can be repaired by reconstructive surgery and/or a dental prosthesis. We present prosthodontic rehabilitation of two maxillary edentulous patients, one with a surgically induced palatal defect and the other with congenital cleft palate. In case 1, an 86-year-old man underwent surgical removal of soft-palate squamous cell carcinoma. The acquired palatal defect was repaired by a maxillary complete denture with a posteriorly extended speech bulb. The final prostheses provided good chewing and speech functions. In case 2, a congenital cleft palate in a 65-year-old man was repaired by a maxillary complete denture with superior extension of the obturator, which was designed to improve retention and stability of the upper single denture. He was satisfied with the upper denture after prosthesis placement. Conventional maxillary complete denture with a posteriorly extended speech bulb or modified obturator provides a good chance to restore oral functions in patients with palatal defects. The patients' skill and previous experience of denture wearing might have been important in their successful treatment. However, different patients present with unique problems and need to be treated individually. Copyright © 2011 Formosan Medical Association & Elsevier. Published by Elsevier B.V. All rights reserved.

  19. Comparing a tablet computer and paper forms for assessing patient-reported outcomes in edentulous patients.

    PubMed

    Caetano, Thais Angelina; Ribeiro, Adriana Barbosa; Della Vecchia, Maria Paula; Cunha, Tatiana Ramirez; Chaves, Carolina de Andrade Lima; de Souza, Raphael Freitas

    2016-12-01

    The aim of this study was to determine whether two methods of documentation, print and electronic forms, for the assessment of patient-reported outcomes (PRO) in complete denture wearers provide comparable results. The study also quantified the time needed for filling the forms by each method. Thirty participants enrolled in a university clinic answered two forms (a questionnaire for denture satisfaction and OHIP-EDENT). They provided answers with two application methods in a random order, with a one-month interval between them: (1) electronic forms on a tablet computer; and (2) print forms. The methods were compared in terms of mean results, correlation/agreement, internal consistency, and spent time. Mean results for both methods were similar for each denture satisfaction item (100-mm VAS) and OHIP-EDENT summary score. Both questionnaires presented good internal consistency regardless of the application method (Cronbach's α=0.86 or higher). Correlation and agreement between the methods regarding specific items was at least moderate for the majority of cases. Mean time for the electronic and print forms were 9.2 and 8.5 minutes, respectively (paired t test, P=.06, non-significant). The electronic method is comparable to print forms for the assessment of important PRO of prosthetic treatment for edentulism, considering the results and time needed. Findings suggest the viability of replacing print forms with a tablet for applying the tested inventories in clinical trials.

  20. Electromyographic Evaluation of the Effect of Lined Dentures on Masticatory Muscle Activity in Edentulous Subjects

    PubMed Central

    Srivastava, Shitij; Gaur, Abhishek; Dupare, Arun; Rastogi, Shiksha; Kamatagi, Laxmikant

    2015-01-01

    Aim The purpose of this study was to examine changes in relative electromyographic (EMG) activities of temporal and masseter muscles after relining the dentures with silicone and acrylic-resin based denture liners. Materials and Methods Conventional complete dentures were fabricated for 20 edentulous patients. One month after completing adjustments of the dentures, electromyography of the masseter and temporalis muscle during maximum intercuspation was recorded. The dentures were then relined with a silicone denture liner and after an adaptation period of one month, were again subjected for electromyographic evaluation. Further, the dentures were relined with acrylic denture liner and subjected to electromyographic evaluation. Data was analysed using Statistical Package for Social Sciences (SPSS) version 15.0. Intergroup comparisons were done using ANOVA followed by post-hoc assessments using Tukey HSD test. Results Mean amplitude and duration with conventional dentures was found to be significantly lower as compared to silicone lined and acrylic lined dentures for all the comparisons. Statistically, no significant difference between silicone lined and acrylic lined dentures was observed for any of the comparisons. Conclusion Within the limitations of this experimental design, it was concluded that relining significantly increases electromyographic activity of the masseter and temporalis muscles. Thus, resulting in an improved biting force, chewing efficiency and masticatory performance. There were no significant differences between silicone and acrylic based denture liners for both electromyographic variables. PMID:26436054

  1. Stability of edentulous, atrophic mandibles after insertion of different dental implants. A biomechanical study.

    PubMed

    Torsiglieri, T; Raith, S; Rau, A; Deppe, H; Hölzle, F; Steiner, T

    2015-06-01

    Fractures of the atrophic edentulous mandible are a rare complication that can become severe after the insertion of dental implants. This in vitro study investigated the effects of different implant settings varying in number, diameter, and length. and the influence of a fixed bar. In biomechanical experiments on artificial mandibles, an unmodified reference group, four implant settings with two different implants, and the effect of adding a fixed bar to these settings were tested. All specimens were loaded with incisal biting forces until failure due to fracture. Implants weakened all specimens significantly compared with those in the reference group. Without a fixed bar, four short and thick implants showed the best results, with high significance. With a fixed bar, four long and thin implants withstood the highest loads. The addition of fixed bars reduced the differences between the implant settings. Fixed bars did not show increased stability for all groups; however, these groups showed a higher mean strength. Four implants with a short and thick design should be the first choice when implants are placed without a fixed bar in an atrophic mandible. With a fixed bar, four long and thin implants should be used. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  2. [Patient satisfaction with removable implant-supported prostheses in the edentulous mandible].

    PubMed

    Zitzmann, Nicola U; Marinello, Carlo P

    2006-01-01

    The aim of the present study was to investigate patients' satisfaction with removable implant restorations with two or four implants compared to a complete denture (CD) in the edentulous mandible. 20 patients in each group were asked to fill out a questionnaire ("Patient satisfaction related to the prosthetic restoration") before treatment, after six months and three years. With implant restorations, either implant-retained (IRET) or implant-supported (ISUP), greater improvements in prostheses retention and pain reduction were achieved in comparison to complete dentures. In addition, restrictions related to food selection were resolved for most implant patients. Despite great inter-individual differences, there was a tendency for larger improvements of almost all parameters with IRET, except chewing ability, which was rated best with ISUP. Long-term results revealed that patients with ISUP (four implants) assessed prostheses retention with the highest ratings compared to those with IRET and CD (p = 0,0147). These results indicate that an improvement in functional and psychological parameters can be achieved with two implants, whilst stabilization with four implants improves prosthesis retention, chewing ability and pain reduction in the long term. Maintenance efforts were more complex for implant restorations than for CD and imply a recall at least once a year.

  3. Rehabilitation of edentulous atrophic anterior mandible - the role of vertical alveolar distraction osteogenesis.

    PubMed

    Mampilly, Mathew O; Rao, Latha P; Sequiera, Joyce; Rao, B H Sripathi; Chandra, Jagadish; Rai, Gunachandra

    2014-11-01

    The rehabilitation of patients with edentulous alveolar ridge is always a challenge, more so in case of a long standing atrophic mandible. Mandible, the largest movable bone in the maxillofacial skeleton is associated with many soft tissue attachments which imparts dislodging forces to prosthesis. In addition to this, the rate of resorption of the mandibular ridge is four times that of the maxilla. These factors make the environment of the mandibular arch less favorable to complete denture stability and retention. An ideal solution would be to augment the atrophic alveolar ridge with native bone of the individual which shall eliminate the possible complications, associated with conventional ridge augmentation procedures. With advent of modern technology, and increased biological understanding, the principles of distraction osteogenesis are increasingly being applied to the craniofacial skeleton and have been found to be a viable option in augmenting the native alveolar bone in the mandible. Here the application of an indigenous stainless steel vertical alveolar distraction device to augment atrophic anterior mandibular ridge is assessed in six patients.

  4. Severely Resorbed Edentulous Ridges: A Preventive Prosthodontic Approach – A Case Report

    PubMed Central

    Karnam, Shalini; Basimi, Swapna; Surapaneni, Haragopal; Basapogu, Sreeramulu

    2015-01-01

    As a dentist our main aim should be prevention which not only includes prevention of caries and or periodontal disease but also prevention of residual alveolar bone loss after teeth are extracted. Today with greater stress on preventive measures, the dental profession has expanded this preventive concept into Prosthodontics. Preventive Prosthodontics emphasizes the importance of any procedure that can delay or eliminate the future Prosthodontic problem and stop further progression of oral disease and prevent the loss of remaining tissues. The Residual Ridge Resorption (RRR) is an inevitable consequence of tooth loss and denture wearing. Severe RRR gradually results in increased interarch distance, significant horizontal discrepancy between edentulous ridges, occurrence of flabby displaceable tissues in the denture bearing area and other sequelae. Prosthetic rehabilitation in these patients can be challenging. The conventional complete denture fabrication in such cases may further compound the poor denture bearing ability of the tissues and lead to decreased retention, stability and support which may result in psychological problems and social isolation. This case report emphasizes the importance of preventive concepts in every step of complete denture fabrication to offer a long serviceable prosthesis without any significant complications and compromise. PMID:26557629

  5. Comparing a tablet computer and paper forms for assessing patient-reported outcomes in edentulous patients

    PubMed Central

    Caetano, Thais Angelina; Ribeiro, Adriana Barbosa; Della Vecchia, Maria Paula; Cunha, Tatiana Ramirez; Chaves, Carolina de Andrade Lima

    2016-01-01

    PURPOSE The aim of this study was to determine whether two methods of documentation, print and electronic forms, for the assessment of patient-reported outcomes (PRO) in complete denture wearers provide comparable results. The study also quantified the time needed for filling the forms by each method. MATERIALS AND METHODS Thirty participants enrolled in a university clinic answered two forms (a questionnaire for denture satisfaction and OHIP-EDENT). They provided answers with two application methods in a random order, with a one-month interval between them: (1) electronic forms on a tablet computer; and (2) print forms. The methods were compared in terms of mean results, correlation/agreement, internal consistency, and spent time. RESULTS Mean results for both methods were similar for each denture satisfaction item (100-mm VAS) and OHIP-EDENT summary score. Both questionnaires presented good internal consistency regardless of the application method (Cronbach's α=0.86 or higher). Correlation and agreement between the methods regarding specific items was at least moderate for the majority of cases. Mean time for the electronic and print forms were 9.2 and 8.5 minutes, respectively (paired t test, P=.06, non-significant). CONCLUSION The electronic method is comparable to print forms for the assessment of important PRO of prosthetic treatment for edentulism, considering the results and time needed. Findings suggest the viability of replacing print forms with a tablet for applying the tested inventories in clinical trials. PMID:28018563

  6. Predicting the final result in implant-supported fixed restorations for completely edentulous patients.

    PubMed

    Kourtis, Stefanos; Kokkinos, Kyriakos; Roussou, Vasiliki

    2014-01-01

    Predicting the final result is a very important factor in implant restorations. When a fixed implant-supported restoration is planned for the restoration of completely edentulous patients, it is important to recognize the esthetic performance of the prosthesis in the initial stages. Bone resorbtion may result in an unfavorable interarch relationship, and soft tissue support may be needed. A detailed presurgical evaluation (including tooth setup, construction of radiological and surgical guide) is needed to ensure the placement of implants in prosthetically favored positions. In this paper, a technique is presented where a detailed wax-up of the restoration is accomplished on provisional implant abutments and tried on the patient after implant placement. This setup may offer valuable information on the expected lip support and the need of gingiva-colored ceramic. In this way, the esthetic result can be evaluated at early stages before any irreversible laboratory stages are performed and needed corrections can be done accordingly. In extended implant-supported fixed restorations, it is very important to predict the final esthetic result at an early stage. The presented technique allows a safe and accurate evaluation of the expected esthetic result before any construction stage. © 2013 Wiley Periodicals, Inc.

  7. Elastic properties and apparent density of human edentulous maxilla and mandible

    PubMed Central

    Seong, Wook-Jin; Kim, Uk-Kyu; Swift, James Q.; Heo, Young-Cheul; Hodges, James S.; Ko, Ching-Chang

    2009-01-01

    The aim of this study aim was to determine whether elastic properties and apparent density of bone differ in different anatomical regions of the maxilla and mandible. Additional analyses assessed how elastic properties and apparent density were related. Four pairs of edentulous maxilla and mandibles were retrieved from fresh human cadavers. Bone samples from four anatomical regions (maxillary anterior, maxillary posterior, mandibular anterior, mandibular posterior) were obtained. Elastic modulus (EM) and hardness (H) were measured using the nano-indentation technique. Bone samples containing cortical and trabecular bone were used to measure composite apparent density (cAD) using Archimedes’ principle. Statistical analyses used repeated measures ANOVA and Pearson correlations. Bone physical properties differed between regions of the maxilla and mandible. Generally, mandible had higher physical property measurements than maxilla. EM and H were higher in posterior than in anterior regions; the reverse was true for cAD. Posterior maxillary cAD was significantly lower than that in the three other regions. PMID:19647417

  8. Rehabilitation of Edentulous Atrophic Anterior Mandible – The Role of Vertical Alveolar Distraction Osteogenesis

    PubMed Central

    Rao, Latha P; Sequiera, Joyce; Rao, B H Sripathi; Chandra, Jagadish; Rai, Gunachandra

    2014-01-01

    The rehabilitation of patients with edentulous alveolar ridge is always a challenge, more so in case of a long standing atrophic mandible. Mandible, the largest movable bone in the maxillofacial skeleton is associated with many soft tissue attachments which imparts dislodging forces to prosthesis. In addition to this, the rate of resorption of the mandibular ridge is four times that of the maxilla. These factors make the environment of the mandibular arch less favorable to complete denture stability and retention. An ideal solution would be to augment the atrophic alveolar ridge with native bone of the individual which shall eliminate the possible complications, associated with conventional ridge augmentation procedures. With advent of modern technology, and increased biological understanding, the principles of distraction osteogenesis are increasingly being applied to the craniofacial skeleton and have been found to be a viable option in augmenting the native alveolar bone in the mandible. Here the application of an indigenous stainless steel vertical alveolar distraction device to augment atrophic anterior mandibular ridge is assessed in six patients. PMID:25584344

  9. Function of a key morphological innovation: fusion of the cichlid pharyngeal jaw

    PubMed Central

    Darrin Hulsey, C

    2005-01-01

    The pharyngeal jaw of cichlids may represent a key innovation that facilitated their unparalleled trophic divergence. In cichlids, ‘fusion’ of the lower pharyngeal jaw (LPJ) results from suturing between the two lower ceratobranchials. To examine, what novel abilities a more extensively fused pharyngeal jaw may confer, the function of LPJ suturing was examined in Heroine cichlids. Greater LPJ suturing, pharyngeal jaw splitting under compression and the forces used to crush molluscs in the wild suggest increased LPJ fusion in the trophically polymorphic Herichthys minckleyi operates to strengthen the pharyngeal jaw. Among Heroine cichlid species, the presence of an external LPJ suture and feeding specialization on molluscs was evolutionarily quite variable, but greater LPJ fusion estimated from the amount of external suturing was highly correlated with molluscivory. Throughout cichlid diversification, increased pharyngeal jaw fusion via suturing has likely helped to reinforce the LPJ during pharyngeal processing thereby facilitating the ability of cichlids to exploit durable prey. PMID:16608685

  10. Efficacy of the Dynamic Jaw Mode in Helical Tomotherapy With Static Ports for Breast Cancer

    PubMed Central

    Manabe, Yoshihiko; Hayashi, Akihiro; Murai, Taro; Takaoka, Taiki; Hattori, Yukiko; Iwata, Hiromitsu; Takenaka, Ran; Shibamoto, Yuta

    2015-01-01

    The recently developed dynamic jaw technology of tomotherapy can reduce craniocaudal dose spread without much prolonging the treatment time. This study aimed to investigate the efficacy of the dynamic jaw mode for tomotherapy of breast cancer. Static tomotherapy plans of the whole breast and supraclavicular regional lymph nodes, and plans for the whole breast only were generated in 25 patients with left-sided breast cancer. Plans with a field width of 2.5 or 5 cm with the dynamic or fixed jaw modes were made for each patient. The prescribed dose was 50 Gy in 25 fractions. In whole breast and supraclavicular nodal radiotherapy, dose distributions and homogeneity of the planning target volume (PTV) with the dynamic jaw mode were slightly inferior to those with the fixed jaw mode with a 5-cm field width (P < .05). However, lung low-dose volumes and mean doses of the larynx, thyroid, skin, and all the healthy tissues combined were smaller with the dynamic jaw mode than with the fixed jaw mode with a 5-cm field width (P < .001). In whole breast radiotherapy, mean doses of the skin and healthy tissues were lower with the dynamic jaw mode than with the fixed jaw mode with a 5-cm field width (P < .001) without significant differences in PTV dose distributions, homogeneity, and conformity. The dynamic jaw mode provided better sparing of organs at risks with minimal disturbance of dose–volume indices of PTV. Considering the treatment time, the 5-cm-field dynamic jaw mode is more efficient than the 2.5-cm fixed jaw mode. PMID:25398681

  11. A comparative study of identical VMAT plans with and without jaw tracking technique.

    PubMed

    Wu, Hao; Jiang, Fan; Yue, Haizhen; Hu, Qiaoqiao; Zhang, Jian; Liu, Zhuolun; Gong, Jian; Li, Sha; Geng, Jianhao; Zhang, Yibao

    2016-09-08

    The unwanted radiation transmission through the multileaf collimators could be reduced by the jaw tracking technique which is commercially available on Varian TrueBeam accelerators. On the basis of identical plans, this study aims to investigate the dosimetric impact of jaw tracking on the volumetric-modulated arc therapy (VMAT) plans. Using Eclipse treatment planning system (TPS), 40 jaw-tracking VMAT plans with various tumor volumes and shapes were optimized. Fixed jaw plans were created by editing the jaw coordinates of the jaw-tracking plans while other parameters were identical. The deliverability of this artificial modification was verified using COMPASS system via three-dimentional gamma analysis between the measurement-based reconstruction and the TPS-calculated dose distribution. Dosimetric parameters of dose-volume histogram (DVH) were compared to assess the improvement of dose sparing for organs at risk (OARs) in jaw-tracking plans. COMPASS measurements demonstrated that over 96.9% of structure volumes achieved gamma values less than 1.00 at criteria of 3 mm/3%. The reduction magnitudes of maximum and mean dose to various OARs ranged between 0.06% ~ 6.76% (0.04 ~ 7.29 Gy) and 0.09% ~ 7.81% (0.02 ~ 2.78 Gy), respectively, using jaw tracking, agreeing with the disparities of radiological characteristics between MLC and jaws. Jaw tracking does not change the delivery efficiency and total monitor units. The dosimetric comparison of VMAT plans with and without jaw tracking confirms the physics hypotheses that reduced transmission through tracking jaws will reduce doses to OARs without sacrificing the target dose coverage because it is meant to be covered by radiation beams going through the opening. © 2016 The Authors.

  12. Modulation of jaw reflexes induced by noxious stimulation to the muscle in anesthetized rats.

    PubMed

    Kurose, Masayuki; Yamamura, Kensuke; Noguchi, Makiko; Inoue, Makoto; Ootaki, Sachiko; Yamada, Yoshiaki

    2005-04-11

    Previous studies have shown that jaw reflexes and activity patterns of the jaw muscles were modulated in the presence of jaw muscle pain. However, there is no study comparing the modulatory effects on the jaw reflexes induced by noxious stimulation to the jaw muscle. To clarify this, effects of the application of mustard oil (MO), an inflammatory irritant, into the temporalis (jaw-closing) muscle on (1) jaw-opening reflex evoked by tooth pulp stimulation (TP-evoked JOR) as a nociceptive reflex, (2) jaw-opening reflex evoked by inferior alveolar nerve stimulation as a non-nociceptive reflex and (3) jaw-closing reflex evoked by trigeminal mesencephalic nucleus stimulation as a proprioceptive reflex were investigated in anesthetized rats. The MO application induced suppression of all reflexes, and the effect on the TP-evoked JOR was more prominent than on the other reflexes. To elucidate the involvement of endogenous opioid system for the suppressive effect, a systemic administration of naloxone following the MO application was conducted. The MO-induced suppressive effect on the TP-evoked JOR was reversed by the naloxone administration. The results suggest that noxious stimulation to the jaw muscle modulate jaw reflexes particularly for the nociceptive jaw-opening reflex, and the modulatory effect includes both facilitatory and inhibitory aspects. The results also suggest that pain modulatory systems such as the endogenous opioid system play a crucial role in the suppression of the nociceptive transmissions related to nociceptive reflexes, and in some pathological states, defense reflexes may not be evoked properly.

  13. A comparative study of identical VMAT plans with and without jaw tracking technique.

    PubMed

    Wu, Hao; Jiang, Fan; Yue, Haizhen; Hu, Qiaoqiao; Zhang, Jian; Liu, Zhuolun; Gong, Jian; Li, Sha; Geng, Jianhao; Zhang, Yibao

    2016-09-01

    The unwanted radiation transmission through the multileaf collimators could be reduced by the jaw tracking technique which is commercially available on Varian TrueBeam accelerators. On the basis of identical plans, this study aims to investigate the dosimetric impact of jaw tracking on the volumetric-modulated arc therapy (VMAT) plans. Using Eclipse treatment planning system (TPS), 40 jaw-tracking VMAT plans with various tumor volumes and shapes were optimized. Fixed jaw plans were created by editing the jaw coordinates of the jaw-tracking plans while other parameters were identical. The deliverability of this artificial modification was verified using COMPASS system via three-dimentional gamma analysis between the measurement-based reconstruction and the TPS-calculated dose distribution. Dosimetric parameters of dose-volume histogram (DVH) were compared to assess the improvement of dose sparing for organs at risk (OARs) in jaw-tracking plans. COMPASS measurements demonstrated that over 96.9% of structure volumes achieved gamma values less than 1.00 at criteria of 3 mm/3%. The reduction magnitudes of maximum and mean dose to various OARs ranged between 0.06%∼6.76%(0.04∼7.29 Gy) and 0.09%∼7.81%(0.02∼2.78 Gy), respectively, using jaw tracking, agreeing with the disparities of radiological characteristics between MLC and jaws. Jaw tracking does not change the delivery efficiency and total monitor units. The dosimetric comparison of VMAT plans with and without jaw tracking confirms the physics hypotheses that reduced transmission through tracking jaws will reduce doses to OARs without sacrificing the target dose coverage because it is meant to be covered by radiation beams going through the opening. PACS number(s): 87.55.de, 87.55.dk.

  14. Built to fight: variable loading conditions and stress distribution in stag beetle jaws.

    PubMed

    Goyens, Jana; Dirckx, Joris; Aerts, Peter

    2015-07-02

    Designing very robust structures in an efficient way is a reoccurring challenge in engineering. For male stag beetle weaponry, the solution to this problem was evolved by natural and sexual selection. Stag beetle armature is adapted to perform under extreme circumstances: male stag beetles fight pugnacious battles over females, by using their extremely large jaws as ferocious weapons. During violent encounters, these jaws have to withstand forces with a wide range of unpredictable directions at several application points. We constructed 1020 finite element models with different input forces to investigate how the male jaws are structurally adapted to avoid failure. The cross-sectional shape of the jaw is adapted to provide robustness against the reaction forces of biting. Nevertheless, the jaw's shape cannot prevent the fact that bite forces induce relatively high material stresses compared to other force directions. Also, males do not confine themselves in combats to bite with the most robust jaw regions. Both observations emphasize the usefulness of bite force modulation to avoid jaw failure. This is likely effectuated by a sensory network in the jaw exoskeleton, as sensor densities are nicely correlated to the maximal material stress caused by 510 different loading directions. Probably, stag beetles use this sensory information to adjust their fighting strategy as well. Finally, male jaws also need to resist the forceful bites inflicted by opponents. Even though this loading applies at other locations along the jaw, and bends the jaw in the opposite direction, our models show that the jaws are equally robust against these external forces as they are against the forces caused by their own biting.

  15. Efficacy of the Dynamic Jaw Mode in Helical Tomotherapy With Static Ports for Breast Cancer.

    PubMed

    Sugie, Chikao; Manabe, Yoshihiko; Hayashi, Akihiro; Murai, Taro; Takaoka, Taiki; Hattori, Yukiko; Iwata, Hiromitsu; Takenaka, Ran; Shibamoto, Yuta

    2015-08-01

    The recently developed dynamic jaw technology of tomotherapy can reduce craniocaudal dose spread without much prolonging the treatment time. This study aimed to investigate the efficacy of the dynamic jaw mode for tomotherapy of breast cancer. Static tomotherapy plans of the whole breast and supraclavicular regional lymph nodes, and plans for the whole breast only were generated in 25 patients with left-sided breast cancer. Plans with a field width of 2.5 or 5 cm with the dynamic or fixed jaw modes were made for each patient. The prescribed dose was 50 Gy in 25 fractions. In whole breast and supraclavicular nodal radiotherapy, dose distributions and homogeneity of the planning target volume (PTV) with the dynamic jaw mode were slightly inferior to those with the fixed jaw mode with a 5-cm field width (P < .05). However, lung low-dose volumes and mean doses of the larynx, thyroid, skin, and all the healthy tissues combined were smaller with the dynamic jaw mode than with the fixed jaw mode with a 5-cm field width (P < .001). In whole breast radiotherapy, mean doses of the skin and healthy tissues were lower with the dynamic jaw mode than with the fixed jaw mode with a 5-cm field width (P < .001) without significant differences in PTV dose distributions, homogeneity, and conformity. The dynamic jaw mode provided better sparing of organs at risks with minimal disturbance of dose-volume indices of PTV. Considering the treatment time, the 5-cm-field dynamic jaw mode is more efficient than the 2.5-cm fixed jaw mode.

  16. Mechanoreceptor distribution in stag beetle jaws corresponds to the material stress in fights.

    PubMed

    Goyens, J; Dirckx, J; Aerts, P

    2015-05-01

    Male stag beetles (Lucanidae) use their extremely elongated jaws to pinch their rivals forcefully in male-male battles. The morphology of these jaws has to be a compromise between robustness (to withstand the bite forces), length and weight. Cyclommatus metallifer stag beetles circumvent this trade-off by reducing their bite force when biting with their slender jaw tips. Here we describe the functional mechanism behind the force modulation behaviour. Scanning Electron Microscopy and micro CT imaging show large numbers of small sensors in the jaw cuticle. We find a strong correlation between the distribution of these sensors and that of the material stress in the same jaw region during biting. The jaw sensors are mechanoreceptors with a small protrusion that barely protrudes above the undulating jaw surface. The sensors stimulate dendrites that extend from the neuronal cell body through the entire thickness of the jaw exoskeleton towards the sensors at the external surface. They form a sensory field that functions in a feedback mechanism to control the bite muscle force. This negative feedback mechanism enabled the stag beetles to evolve massive bite muscles without risking overloading their valuable jaws.

  17. The retro-articular process, streptostyly and the caecilian jaw closing system.

    PubMed

    Summers, Adam P; Wake, Marvalee H

    2005-01-01

    Caecilians have two functionally separate sets of jaw closing muscles. The jaw adductor muscles are parallel fibered muscles positioned close to the jaw joint and their lever mechanics suggests they are well suited to rapidly closing the jaws. A second set of muscles, the hypaxial interhyoideus posterior (IHP), levers the jaws closed by pulling on the retro-articular process (RA) of the lower jaw. Models of the lower jaw point out that the angle and length of the RA has a profound effect on the closure force exerted by the IHP. The caecilian skull is streptostylic - the quadrate-squamosal apparatus (QSA) moves relative to the rest of the skull, a condition that seems at odds with a well-ossified cranium. Modeling the contribution of this streptostylic suspension of the lower jaw shows that rotational freedom of the QSA amplifies the force of the IHP by redirecting force applied along the low axis of the lower jaw. Measurements from several species and life stages of preserved caecilians reveal a large variation in predicted bite force (as a multiple of IHP force) with age and phylogeny.

  18. The combination of a nylon and traditional partial removable dental prosthesis for improved esthetics: a clinical report.

    PubMed

    Ito, Masayasu; Wee, Alvin G; Miyamoto, Takanari; Kawai, Yasuhiko

    2013-01-01

    A benefit of a nylon partial removable dental prosthesis (PRDP) is the absence of a metal framework, providing improved esthetics. Unfortunately, the lack of a traditional framework reduces rigidity and the support of occlusal rests. This clinical report describes a combination of a nylon PRDP (polyamide denture base resin) and a traditional PRDP (framework/resin) for a Kennedy Class II, Modification 1, partially edentulous mandible. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  19. Tilted Implants for Full-Arch Rehabilitations in Completely Edentulous Maxilla: A Retrospective Study

    PubMed Central

    Cavalli, Nicolò; Barbaro, Bruno; Spasari, Davide; Azzola, Francesco; Ciatti, Alberto; Francetti, Luca

    2012-01-01

    Purpose. The aims of this study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants in the edentulous maxilla and to evaluate the incidence of biological and prosthetic complications. Materials and Methods. Thirty-four patients (18 women and 16 men) were included in the study. Each patient received a maxillary full-arch fixed bridge supported by two axial implants and two distal tilted implants. A total of 136 implants were inserted. Loading was applied within 48 hours of surgery and definitive restorations were placed 4 to 6 months later. Patients were scheduled for followup at 6, 12, 18, and 24 months and annually up to 5 years. At each followup plaque level and bleeding scores were assessed and every complication was recorded. Results. The overall follow-up range was 12 to 73 mon