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Sample records for molars anatomical aspects

  1. The maxillary second molar - anatomical variations (case report).

    PubMed

    Beshkenadze, E; Chipashvili, N

    2015-01-01

    To be acquainted with dental anatomical specificity is of great importance for dental endodontic treatment algorithm. The subject of present publication is 2 clinical cases of upper second molars, detailed characterization of, which is considered very important for enrichment of anatomical knowledge about dental anatomical variations. In one case, the reason for admission to the clinic of a 38-year-old woman was complains as of esthetic character as well as functional misbalance (disturbance of chewing function due to the damage of orthopedic construction). The patient indicated to the existence of coronary defects of large size aesthetic discomforts, damage and discolouration of old orthopedic construction (denture) in maxillary right molar area. According to the data obtained after clinical and visiographical examinations, chronic periodontitis of 17 teeth was identified as a result of incomplete endodontic treatment. According to the data obtained after clinical and visiographical examinations, the diagnosis of chronic periodontitis of 17 teeth was identified, tooth 17 with 2 roots and 2 canals. In the second clinical case, the reason for admission to the clinic of a 39-year-old woman was severe pain in the upper right molar area. The patient indicated to the caries on the tooth 17. After completion of proper survey clinical and visiographical examinations, acute pulpitis (K04.00) - with three roots and 4 canals was diagnosed. In both cases after the proper examinations and agreement with the patients a treatment plan envisaging: 17 teeth endodontic treatment, filling of caries defects and their preparation on one hand for orthopedic construction (denture) and on the other hand for restoration of anatomical integrity by light-cured composite, was scheduled. The present study is designed to prevent complications of endodontic treatment of the second molar, to optimize diagnosis and treatment algorithm, once again proving reliable information indicating to the

  2. Anatomically guided implant site preparation technique at molar sites.

    PubMed

    Rodriguez-Tizcareño, Mario H; Bravo-Flores, Claudia

    2009-10-01

    Immediate postextraction implant placement in the areas of multiradicular teeth is a difficult procedure in view of having to place the implant in an ideal position without jeopardizing its initial stability. The surgeon often faces the problem of directing the initial osteotomy in the medial portion of the alveolus with the difficulty of engaging the inter-radicular septum of the extraction socket. The drill may slip continually leading to an inaccurate site preparation, and consequently to a deficient implant insertion. The fixture is often placed directly into either one of the extraction sockets of the tooth to be replaced. The anatomically guided site preparation technique is a very useful tool to perform implant placement in the areas of multiradicular teeth. This approach of implant insertion consists of a progressive preparation of the implant site using the anatomy and geometry of the root of the multiradicular teeth to be extracted as a reference and as an aid to engage the inter-radicular septum. This places the implants in a favorable and proper position from a biomechanical and occlusal standpoint. The objective of this article is to describe the anatomically guided implant site preparation technique as an aid to favorably place dental implants in multiradicular teeth postextraction. PMID:22129957

  3. Anatomical Relationship of Lingual Nerve to the Region of Mandibular Third Molar

    PubMed Central

    de Carvalho Leite Leal Nunes, Carla Maria; de Almeida Lopes, Maria Cândida

    2013-01-01

    ABSTRACT Objectives This study evaluated the relationship of the lingual nerve with the adjacent anatomical structures of the mandibular third molar region, influencing the dentist to be aware of the variability of these relationships. Material and Methods Samples of 24 human corpse half-heads were selected and divided according with the presence or absence of the mandibular third molars. The lingual nerve (LN) was explored, showing its run from the oblique line until its crossing with the submandibular gland duct. The measurements along the LN and the adjacent anatomical structures were taken at the retromolar, molar and sublingual region with the use of a digital caliper. Results The distance from the LN and the third molar socket, which represents the horizontal distance of the lingual plate to the nerve, on average, was 4.4 mm (SD 2.4 mm). The distance from the LN and the lingual alveolar rim, which represents the vertical relationship between the nerve and the lingual alveolar rim of the third molar socket, on average, was 16.8 mm (SD 5.7 mm). The LN has a varied topography that leaves it very vulnerable during any procedure executed in this region. Conclusions Unless adequate protection of the lingual nerve is acquired by following an adequate surgical technique, the lingual nerve will always be vulnerable to damage during surgical intervention or manipulation in this region. PMID:24478912

  4. Anatomical and clinical aspects of Klinefelter's syndrome.

    PubMed

    Bird, Rebecca J; Hurren, Bradley J

    2016-07-01

    Klinefelter's syndrome, the most common sex disorder associated with chromosomal aberrations, is characterized by a plethora of clinical features. Parameters for diagnosis of the syndrome are constantly expanding as new anatomical and hormonal abnormalities are noted, yet Klinefelter's remains underdiagnosed and underreported. This review outlines the key anatomical characteristics associated with the syndrome, which are currently used for clinical diagnosis, or may provide means for improving diagnosis in the future. Clin. Anat. 29:606-619, 2016. © 2016 Wiley Periodicals, Inc. PMID:26823086

  5. Anatomical aspects of angiosperm root evolution

    PubMed Central

    Seago, James L.; Fernando, Danilo D.

    2013-01-01

    Background and Aims Anatomy had been one of the foundations in our understanding of plant evolutionary trends and, although recent evo-devo concepts are mostly based on molecular genetics, classical structural information remains useful as ever. Of the various plant organs, the roots have been the least studied, primarily because of the difficulty in obtaining materials, particularly from large woody species. Therefore, this review aims to provide an overview of the information that has accumulated on the anatomy of angiosperm roots and to present possible evolutionary trends between representatives of the major angiosperm clades. Scope This review covers an overview of the various aspects of the evolutionary origin of the root. The results and discussion focus on angiosperm root anatomy and evolution covering representatives from basal angiosperms, magnoliids, monocots and eudicots. We use information from the literature as well as new data from our own research. Key Findings The organization of the root apical meristem (RAM) of Nymphaeales allows for the ground meristem and protoderm to be derived from the same group of initials, similar to those of the monocots, whereas in Amborellales, magnoliids and eudicots, it is their protoderm and lateral rootcap which are derived from the same group of initials. Most members of Nymphaeales are similar to monocots in having ephemeral primary roots and so adventitious roots predominate, whereas Amborellales, Austrobaileyales, magnoliids and eudicots are generally characterized by having primary roots that give rise to a taproot system. Nymphaeales and monocots often have polyarch (heptarch or more) steles, whereas the rest of the basal angiosperms, magnoliids and eudicots usually have diarch to hexarch steles. Conclusions Angiosperms exhibit highly varied structural patterns in RAM organization; cortex, epidermis and rootcap origins; and stele patterns. Generally, however, Amborellales, magnoliids and, possibly

  6. Morphologic Measurements of Anatomic Landmarks in Pulp Chambers of Human First Molars: A Study of Bitewing Radiographs

    PubMed Central

    Khojastepour, Leila; Rahimizadeh, Naser; Khayat, Akbar

    2008-01-01

    INTRODUCTION: Knowledge of the anatomic location and dimension of the molar pulp chamber may preserve healthy pulp during operative procedure and reduce risk of perforation of chamber during access preparation. A review of literatures regarding the morphology of pulp chamber however revealed very little information; so the aim of this in vivo study was to measure the dimensions of first molar pulp chambers as seen on bitewing (BW) radiographs. MATERIALS AND METHODS: In this cross-sectional study molar's BW radiographs of 130 subjects in two age groups were taken under standardized conditions (group of 18-25 years old subjects and group of 50-65 years old subjects). The films were digitized and nine anatomical landmarks were evaluated from the image of each first molar as follow: A; mesial to distal pulp horn distance, B; mesial to distal walls at the middle of pulp chamber, C; mesial to distal orifices, D; mesial cusp tip to its horn, E; distal cusp tip to its horn, F; pulp chamber height, G; pulp chamber floor to furcation, H; pulp chamber ceiling to furcation, I; cusp tips to furcation. The data were evaluated by using AUTOCAD (2007) software with 0.00 precision. Two way ANOVA test (Uni-variant analysis) were used to determine the interaction between restoration and age on pulp chamber dimensions. RESULTS: There was no significant difference in pulp chamber dimensions between the genders. Although there was significant reduction in the size of pulp chamber with advancing age, no significant differences were found in the restored and non restored teeth. CONCLUSION: The finding of this study showed size reduction and changes of pulp chamber with age so may enhance knowledge to minimize errors during endodontics treatments. PMID:24265638

  7. Anatomical study of C-shaped canals in mandibular second molars by analysis of computed tomography.

    PubMed

    Jin, Guang-Chun; Lee, Seong-Jong; Roh, Byoung-Duck

    2006-01-01

    The aim of this study was to investigate the prevalence and configuration of the C-shaped canal using serial axial computed tomography images of the mandibular second molars that had not been restored severely or treated endodontically, and to compare the thickness of the remaining tooth structure from the center of the canal to the outer surface of the deepest groove area in C-shaped mandibular second molar to that of "danger zone of perforation" in normal mandibular second molar. This distance was measured at the cervical, middle, and apical third level each. From 220 teeth, C-shaped canals were found in 98 teeth (44.5%). Almost all the grooves were directed lingual (99%). The continuous C-shaped canal was the most frequently found (49%) and the separated canal was the least (17.4%). The thinnest remaining tooth structure in the groove area of the C-shaped mandibular second molar was not different from that of the danger zone of normal mandibular second molar at the three levels (p > 0.05). PMID:16410060

  8. Morphological measurements of anatomic landmarks in human maxillary and mandibular molar pulp chambers.

    PubMed

    Deutsch, Allan S; Musikant, Barry Lee

    2004-06-01

    The aim of this in vitro study was to measure critical morphology of molar pulp chambers. One hundred random human maxillary and mandibular molars (200 teeth in total) were used. Each molar was radiographed mesiodistally on a millimeter grid. Using a stereomicroscope, the measurements were read to the nearest 0.5 mm. Results were as follows (mean, mm): pulp chamber floor to furcation, maxillary = 3.05 +/- 0.79, mandibular = 2.96 +/- 0.78; pulp chamber ceiling to furcation, maxillary = 4.91 +/- 1.06, mandibular = 4.55 +/- 0.91; buccal cusp to furcation, maxillary = 11.15 +/- 1.21, mandibular = 10.90 +/- 1.21; buccal cusp to pulp chamber floor, maxillary = 8.08 +/- 0.88, mandibular = 7.95 +/- 0.79; buccal cusp to pulp chamber ceiling, maxillary = 6.24 +/- 0.88, mandibular = 6.36 +/- 0.93; and pulp chamber height, maxillary = 1.88 +/- 0.69, mandibular = 1.57 +/- 0.68. The pulp chamber ceiling was at the level of the cementoenamel junction in maxillary, 98%, and mandibular, 97% of the specimens. The measurements showing the lowest percentage variance were buccal cusp to furcation (approximately 11%) and buccal cusp to pulp chamber ceiling (approximately 14%). The measurements were similar for both maxillary and mandibular molars. PMID:15167463

  9. Reproductive system of females of the Magdalena river endemic stingray Potamotrygon magdalenae: Anatomical and functional aspects.

    PubMed

    del Mar Pedreros-Sierra, Tania; Arrieta-Prieto, Dagoberto M; Mejía-Falla, Paola A

    2016-05-01

    We studied anatomical and functional aspects of the reproductive system of females of the Magdalena river stingray Potamotrygon magdalenae using microscopic and macroscopic analysis of each organ. Although the reproductive tract was fully functional on both side, the left organs possibly have a greater contribution to reproductive success, because left ovary and uterus were more developed and had higher number of oocytes and embryos, respectively, than the right ones. This species has histotrophic viviparity given by the presence of uterine trophonemata and by glandular character in pregnant and postpartum females. We suggest that the epigonal organ is involved in the degradation of components of atretic follicles and the embryos begin to develop surrounded by a gelatinous tertiary envelope produced by the oviducal gland. This latter organ is composed by three zones in mature females, club, papillary, and baffle zone, as described for other elasmobranchs. From the anatomical observations, a maturity scale comprising six sexual maturity stages (Immature I, Immature II, early mature, pregnant, post-partum, and regenerating) was established for female P. magdalenae, and it can be useful as basis for reproductive studies of other potamotrygonid species. Finally, we propose a continuous reproductive cycle for P. magdalenae. PMID:26968745

  10. Selection of an animal model for implant fixation studies: anatomical aspects.

    PubMed Central

    Goel, V. K.; Drinker, H.; Panjabi, M. M.; Strongwater, A.

    1982-01-01

    A number of different animal models have been employed by investigators to study the biology of the bone-cement interface as it relates to the problem of hip implant loosening in humans. This study compares to the human three species (baboon, dog, and sheep) currently under use as experimental animal models from an anatomical point of view. A number of parameters, important for the dimensional design of a femoral prosthesis, loads at the hip joint and its subsequent performance, were used for comparing external and internal femoral anatomy. The baboon and dog femora were found to be most similar to the human femur in their external anatomy. The quantification of cancellous bone distribution within the medullary canal revealed that, of the species studied, the sheep femur provided the least support to the prosthesis. The results suggest that the dog and baboon are anatomically appropriate for studying hip implant biomechanics experimentally. Thus, from an anatomical point of view, the current extensive use of the dog as an experimental animal appears appropriate. Images FIG. 3 FIG. 4 PMID:7136007

  11. Comparing and authenticating on anatomical aspects of Abrus cantoniensis and Abrus mollis by microscopy

    PubMed Central

    Zhang, Zhifeng; Lu, Luyang; Liu, Yuan; Qing, Linsen

    2015-01-01

    Background: Abrus cantoniensis is popularly used as traditional Chinese medicine and a cool tea in South of China. However, due to diminishing source of A. cantoniensis, it is usually interchanged or adulterated with other species of Abrus genus because of the limited knowledge in identification and differentiation. Especially, Abrus mollis is widely mixed on herbal markets and pharmaceutical preparation. Objective: To ensure safety and efficacy, a detailed comparison was undertaken to carry out an anatomical and micro-morphological study of two species of A. cantoniensis and A. mollis. Materials and Methods: Microscopic characteristics of roots, leaves and stems, including transverse sections and the crude drug powder, were observed using a light microscope according to the usual microscopic techniques. Results: The basic diagnostic features of A. cantoniensis include that stem is extremely thin; xylem vessels of root are radially arranged in 10 or more bundles; pith is hollow in stem, and the palisade tissue is made up of two layers of palisade cells. Furthermore, scanning electron microscopy was used to compare nonglandular hairs and the stomata of the leaflet surface. A table of the key authentication parameters based on the analyzed microscopic characteristics was drawn up. Conclusion: The study demonstrated that the microscopy and related techniques provided a systematic method that is convenient, feasible, and can be unambiguously applied to the authentication of the species of Abrus. PMID:25829788

  12. Diseases in the cranio-cervical junction: Anatomical and pathological aspects and detailed clinical accounts

    SciTech Connect

    Voth, D.; Glees, P.

    1987-01-01

    This book contains over 40 selections. Some of the titles are: Radionuclide imaging of the cranio-cervical region; Magnetic resonance imaging in the cranio-cervical region: Experiences in 194 cases; NMR-finding in a case of Morquio's syndrome with syncope; The dynamic evaluation of the cervical spinal canal and spinal cord by magnetic resonance imaging during movement; and A review of clinical and radiological aspects of rheumatoid arthritis of head joints.

  13. Rats show molar sensitivity to different aspects of random-interval-with-linear-feedback-functions and random-ratio schedules.

    PubMed

    Reed, Phil

    2015-10-01

    Three experiments examined the impact of various aspects of reinforcement contingencies on responding maintained by free-operant schedules by food-deprived rats. Experiment 1 demonstrated that random interval (RI) and random-interval-with-positive-response-reinforcer-feedback (RI+) schedules maintained similar rates of responding at a variety of reinforcer frequencies. Experiment 2 demonstrated that a random ratio (RR) schedule maintained higher rates than RI or RI+ schedules, except at high rates of reinforcement, where response rates were similar on all schedules. Experiment 3 again demonstrated that RR schedules produced higher response rates than either RI or RI+ schedules, but modification of the RI+ schedule to prevent ratio strain enhanced response rates relative to an RI schedule. Together these results reveal a pattern of interacting factors in schedule controlled behavior: at high rates of reinforcement, this factor overrides the impact of other controlling factors, but as reinforcement rate decreases the joint impact of interresponse times reinforcement, response-reinforcer feedback functions, and ratio strain are observed. PMID:25915752

  14. Maxillary First Molar with Two Root Canals

    PubMed Central

    Rahimi, Saeed; Ghasemi, Negin

    2013-01-01

    Knowledge regarding the anatomic morphology of maxillary molars is absolutely essential for the success of endodontic treatment. The morphology of the permanent maxillary first molar has been reviewed extensively; however, the presence of two canals in a two-rooted maxillary first molar has rarely been reported in studies describing tooth and root canal anatomies. This case report presents a patient with a maxillary first molar with two roots and two root canals, who was referred to the Department of Endodontics, Tabriz University of Medical Sciences, Iran. PMID:23862051

  15. Endodontic treatment of molars

    PubMed Central

    Habl, Claudia; Bodenwinkler, Andrea; Stürzlinger, Heidi

    2006-01-01

    Objective Commissioned by the German Institute of Medical Documentation and Information (DIMDI) the Austrian Health Institute (ÖBIG) prepared a HTA report on the long-term effectiveness of endodontic treatment (root canal treatment, RCT) of molars. The focus is to examine factors influencing the outcome of endodontic treatment and showing their impact on long-term results. Additionally, economic aspects of root canal treatment in Germany are discussed. Methodology By performing a systematic literature search in 29 databases (e.g. MEDLINE), the Cochrane Library and by hand searching two peer-reviewed endodontic journals the authors could identify 750 relevant articles, of which finally 18 qualified for assessment. Results The findings show that the most relevant factor influencing the long-term outcome of endodontic treatment is the preoperative status of a tooth. The lowest success rates are reported for molars with a preoperative devital or necrotic pulp and persisting periapical lesions (so called periapical disease). Discussion Even if there is no positive selection of patients and the RCT is performed by a normal dentist rather than an endodontist - a fact which is very common - long-term success rates of more then 90% are possible. The overall success rates for endodontic treatment of molars therefore seem to be similar to those of other tooth-types. Conclusions Especially primary, conventional (i.e. non-surgical) root canal treatment is an effective and efficient therapy for endodontically ill molars, especially if no large periapical lesion persists. Nonetheless, a long term successful endodontic therapy requires a thorough assessment of the pre-operative status of the molar and treatment according to established guidelines. PMID:21289954

  16. Single-rooted primary first mandibular molar

    PubMed Central

    Haridoss, SelvaKumar; Swaminathan, Kavitha; Rajendran, Vijayakumar; Rajendran, Bharathan

    2014-01-01

    Morphological variations like single-rooted molar in primary dentition are scarce. Understanding the root canal anatomy and variations is necessary for successful root canal therapy. The purpose of the present article is to report successful endodontic treatment of primary left mandibular first molar with an abnormal morphology of a single root. This case report highlights the importance of knowledge and its applications in the management of anomalous anatomic variants which play a crucial role in the success of endodontic treatment. PMID:25150245

  17. Deciduous molar hypomineralization and molar incisor hypomineralization.

    PubMed

    Elfrink, M E C; ten Cate, J M; Jaddoe, V W V; Hofman, A; Moll, H A; Veerkamp, J S J

    2012-06-01

    This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. This study focused on the relationship between Deciduous Molar Hypomineralization (DMH) and Molar Incisor Hypomineralization (MIH). First permanent molars develop during a period similar to that of second primary molars, with possible comparable risk factors for hypomineralization. Children with DMH have a greater risk of developing MIH. Clinical photographs of clean, moist teeth were taken with an intra-oral camera in 6,161 children (49.8% girls; mean age 74.3 mos, SD ± 5.8). First permanent molars and second primary molars were scored with respect to DMH or MIH. The prevalence of DMH and MIH was 9.0% and 8.7% at child level, and 4.0% and 5.4% at tooth level. The Odds Ratio for MIH based on DMH was 4.4 (95% CI, 3.1-6.4). The relationship between the occurrence of DMH and MIH suggests a shared cause and indicates that, clinically, DMH can be used as a predictor for MIH. PMID:22370445

  18. Role of third molars in orthodontics.

    PubMed

    Almpani, Konstantinia; Kolokitha, Olga-Elpis

    2015-02-16

    The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not been discussed at the same level is their involvement in orthodontic therapy. The aim of this study is to present a review of the contemporary literature regarding the most broadly discussed aspects of the multifactorial role of third molars in orthodontics and which are of general dental interest too. PMID:25685759

  19. Autotransplantation of Mandibular Third Molar: A Case Report

    PubMed Central

    Ravi kumar, Pabbati; Jyothi, Mandava; Sirisha, Kantheti; Racca, Khushboo; Uma, Chalasani

    2012-01-01

    Autogenous transplantation is a feasible, fast, and economical option for the treatment of nonsalvageable teeth when a suitable donor tooth is available. This paper presents successful autotransplantation of a mature mandibular left third molar (38) without anatomical variances is used to replace a mandibular left second molar (37). The mandibular second molar was nonrestorable due to extensive root caries and resorption of distal root. After extraction of mandibular second and third molars, root canal therapy was done for the third molar extraorally, and the tooth was reimplanted into the extracted socket of second molar site. After one year, clinical and radiographic examination revealed satisfactory outcome with no signs or symptoms suggestive of pathology. In selected cases, autogenous tooth transplantation, even after complete root formation of the donor tooth, may be considered as a practical treatment alternative to conventional prosthetic rehabilitation or implant treatment. PMID:23346422

  20. Clinical significance of computed tomography assessment for third molar surgery.

    PubMed

    Nakamori, Kenji; Tomihara, Kei; Noguchi, Makoto

    2014-07-28

    Surgical extraction of the third molar is the most commonly performed surgical procedure in the clinical practice of oral surgery. Third molar surgery is warranted when there is inadequate space for eruption, malpositioning, or risk for cyst or odontogenic tumor formation. Preoperative assessment should include a detailed morphologic analysis of the third molar and its relationship to adjacent structures and surrounding tissues. Due to developments in medical engineering technology, computed tomography (CT) now plays a critical role in providing the clear images required for adequate assessment prior to third molar surgery. Removal of the maxillary third molar is associated with a risk for maxillary sinus perforation, whereas removal of the mandibular third molar can put patients at risk for a neurosensory deficit from damage to the lingual nerve or inferior alveolar nerve. Multiple factors, including demographic, anatomic, and treatment-related factors, influence the incidence of nerve injury during or following removal of the third molar. CT assessment of the third molar prior to surgery can identify some of these risk factors, such as the absence of cortication between the mandibular third molar and the inferior alveolar canal, prior to surgery to reduce the risk for nerve damage. This topic highlight presents an overview of the clinical significance of CT assessment in third molar surgery. PMID:25071882

  1. Clinical significance of computed tomography assessment for third molar surgery

    PubMed Central

    Nakamori, Kenji; Tomihara, Kei; Noguchi, Makoto

    2014-01-01

    Surgical extraction of the third molar is the most commonly performed surgical procedure in the clinical practice of oral surgery. Third molar surgery is warranted when there is inadequate space for eruption, malpositioning, or risk for cyst or odontogenic tumor formation. Preoperative assessment should include a detailed morphologic analysis of the third molar and its relationship to adjacent structures and surrounding tissues. Due to developments in medical engineering technology, computed tomography (CT) now plays a critical role in providing the clear images required for adequate assessment prior to third molar surgery. Removal of the maxillary third molar is associated with a risk for maxillary sinus perforation, whereas removal of the mandibular third molar can put patients at risk for a neurosensory deficit from damage to the lingual nerve or inferior alveolar nerve. Multiple factors, including demographic, anatomic, and treatment-related factors, influence the incidence of nerve injury during or following removal of the third molar. CT assessment of the third molar prior to surgery can identify some of these risk factors, such as the absence of cortication between the mandibular third molar and the inferior alveolar canal, prior to surgery to reduce the risk for nerve damage. This topic highlight presents an overview of the clinical significance of CT assessment in third molar surgery. PMID:25071882

  2. Five Canalled and Three-Rooted Primary Second Mandibular Molar

    PubMed Central

    Selvakumar, Haridoss; Kavitha, Swaminathan; Bharathan, Rajendran; Varghese, Jacob Sam

    2014-01-01

    A thorough knowledge of root canal anatomy and its variation is necessary for successful completion of root canal procedures. Morphological variations such as additional root canals in human deciduous dentition are rare. A mandibular second primary molar with more than four canals is an interesting example of anatomic variations, especially when three of these canals are located in the distal root. This case shows a rare anatomic configuration and points out the importance of looking for additional canals. PMID:25147744

  3. Five canalled and three-rooted primary second mandibular molar.

    PubMed

    Selvakumar, Haridoss; Kavitha, Swaminathan; Bharathan, Rajendran; Varghese, Jacob Sam

    2014-01-01

    A thorough knowledge of root canal anatomy and its variation is necessary for successful completion of root canal procedures. Morphological variations such as additional root canals in human deciduous dentition are rare. A mandibular second primary molar with more than four canals is an interesting example of anatomic variations, especially when three of these canals are located in the distal root. This case shows a rare anatomic configuration and points out the importance of looking for additional canals. PMID:25147744

  4. Ruptured tubal molar pregnancy.

    PubMed

    Yakasai, I A; Adamu, N; Galadanchi, H S

    2012-01-01

    Molar pregnancies in most instances develop within the uterine cavity, but may occur at any site. Ectopic molar pregnancy is a rare event. The objective of this study was to present a case of ruptured tubal molar gestation, discuss its clinical features and ways to improve diagnostic accuracy. A 35-year-old woman presented with features suggestive of ruptured tubal ectopic pregnancy. There was neither any evidence at the time of presentation to suspect a molar gestation, nor β human chorionic gonadotrophin (βhCG) hormone estimation was done, but only a clearview pregnancy test was carried out. She had total left salpingectomy and histological evaluation of the specimen revealed complete hydatidiform mole. The hCG level normalized within 3 weeks of follow-up. Clinical features of ectopic molar pregnancy may be indistinguishable from non-molar ectopic pregnancy. We recommend βhCG estimation as well as histological examination of the surgical specimen for all patients coming with features suggestive of ectopic pregnancy. PMID:23238205

  5. Mandibular Third Molar Impaction: Review of Literature and a Proposal of a Classification

    PubMed Central

    Daugela, Povilas

    2013-01-01

    ABSTRACT Objectives The purpose of present article was to review impacted mandibular third molar aetiology, clinical anatomy, radiologic examination, surgical treatment and possible complications, as well as to create new mandibular third molar impaction and extraction difficulty degree classification based on anatomical and radiologic findings and literature review results. Material and Methods Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular third molar, impacted mandibular third molar, inferior alveolar nerve injury third molar, lingual nerve injury third molar. The search was restricted to English language articles, published from 1976 to April 2013. Additionally, a manual search in the major anatomy and oral surgery journals and books was performed. The publications there selected by including clinical and human anatomy studies. Results In total 75 literature sources were obtained and reviewed. Impacted mandibular third molar aetiology, clinical anatomy, radiographic examination, surgical extraction of and possible complications, classifications and risk factors were discussed. New mandibular third molar impaction and extraction difficulty degree classification based on anatomical and radiologic findings and literature review results was proposed. Conclusions The classification proposed here based on anatomical and radiological impacted mandibular third molar features is promising to be a helpful tool for impacted tooth assessment as well as for planning for surgical operation. Further clinical studies should be conducted for new classification validation and reliability evaluation. PMID:24422029

  6. A Clinical Evaluation of Anatomic Features of Gingiva in Dental Students in Tabriz, Iran

    PubMed Central

    Shirmohammadi, Adileh; Faramarzie, Masoumeh; Lafzi, Ardeshir

    2008-01-01

    Background and aims The anatomical features of gingiva are important in appropriate periodontal treatment planning. This study was designed to determine the anatomic features of gingival in a group of dental students in Tabriz, Iran. Materials and methods One-hundred healthy subjects (aged 20-24 years old) with no history of periodontal or orthodontic treatment and a gingival index of zero or one were included. The following measurements were made using a periodontal probe: the distance between the gingival margin and base of gingival sulcus (depth of sulcus); the distance between the gingival margin and mucogingival junction (keratinized gingiva); and the distance between base of gingival sulcus and mucogingival junction (attached gingiva). Existence of free gingival groove was also recorded by observation. Mean values of collected data were calculated. Results The widest attached gingiva and keratin-ized gingiva on the buccal aspect was seen in upper lateral incisor and their minimum in lower premo-lars. The maximum depth of sulcus on the buccal surface was recorded in upper right molar and its minimum on the buccal surface was found in lower left canine. All of the studied students had free gin-gival groove on the buccal or oral aspect of at least one tooth. Conclusion The anatomic features found in this study were similar to those of the previous studies. However, mild variations with regard to race differ-ences were observed. PMID:23277852

  7. Molar Incisor Hypomineralization.

    PubMed

    Rao, Murali H; Aluru, Srikanth C; Jayam, Cheranjeevi; Bandlapalli, Anila; Patel, Nikunj

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect affecting teeth. High prevalence rates of MIH and its clinical implications are significant for both the patients and clinicians. A wide variation in defect prevalence (2.4-40.2%) is reported. It seems to differ with regions and various birth cohorts. Some of the recent prevalence studies are tabulated. Patient implications include hypersensitive teeth, rapid progression of caries, mastication impairment due to rapid attrition, and esthetic repercussions. Implications for clinicians include complexity in treatment planning and treatment implementation, poor prognosis of the restorations, difficulty in achieving pain control during treatment, and behavior management problems. Intention of this paper is to review the etio-pathogenesis, prevalence, clinical features, diagnostic features, and eventually present a sequential treatment approach, i.e., in accordance with current clinical practice guidelines. PMID:27595731

  8. Lower molar and incisor displacement associated with mandibular remodeling.

    PubMed

    Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L

    1997-01-01

    The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla. PMID:9107373

  9. Patients' anxieties with third molar surgery.

    PubMed

    Earl, P

    1994-10-01

    There has been little study of patients' anxieties about third molar surgery despite its widespread practice. 105 patients were invited to complete questionnaires preoperatively to assess anxieties about the procedure and to assess how well it was explained. They were also asked post operatively to assess differences from expectations, accuracy of the preoperative explanation and which aspect would worry them most should the procedure be repeated. Patients generally found their worries as expected or even better. Few found events worse with only pain (12%) and paraesthesia (13%) of note. Although 88% of patients assessed pain as better than or as expected, 43% would fear it most if the procedure was repeated. Pain is the single most feared factor despite evidence that it is usually no worse than originally feared. Reassurance and adequate pain control are the most important factors to patients in third molar surgery, and this reassurance should start at operation booking rather than on admission. PMID:7999736

  10. Controversy of the third molars.

    PubMed

    Pitekova, L; Satko, I

    2009-01-01

    Third molars are teeth that have little functional value and a relatively high rate of associated pain and disease. Their value as a part of the dentition of modern people is dubious. Our aim is to review the evolution, morbidity and complications of the third molars (Ref. 19). Full Text (Free, PDF) www.bmj.sk. PMID:19408843

  11. Anatomical study of total cystoprostatectomy.

    PubMed

    Benoit, G; Boccon-Gibod, L; Steg, A

    1985-01-01

    The authors describe an anatomical study of total cystoprostatectomy. They show that Denonvilliers' fascia is made up of many membranous layers starting at the bladder. They recall the fact that the preprostatic veins are attached at the bottom, not only to the venae dorsales penis, but also to the venae pudendae internae which runs under the levator ani muscle. These preprostatic veins lie inside a vessel-bearing blade of tissue made of muscular and collagenous tissue derived from the anterior vesical wall. This anatomical study recalls the fact that the interprostatorectal dissection line is behind Denonvilliers' fascia and that the preprostatic vein dissection line is on the anterior aspect of the membranous urethra. PMID:4043160

  12. Root Canal Therapy of a Mandibular First Molar with Five Root Canals: A Case Report

    PubMed Central

    Reyhani, Mohammad Frough; Rahimi, Saeed; Shahi, Shahriar

    2007-01-01

    A mandibular first molar requiring root canal therapy was found with five canals, three mesial canals, and two distal canals. Initially, four canals (mesiobuccal, mesiolingual, distobuccal, and distolingual) were identified. The mesiobuccal and mesiolingual canals were found in their normal locations, and a fifth canal was noted between these two. This case demonstrates a rare anatomical configuration and supplements previous reports of the existence of such configurations in mandibular first molars. PMID:24298291

  13. 3D imaging reconstruction and impacted third molars: case reports

    PubMed Central

    Tuzi, Andrea; Di Bari, Roberto; Cicconetti, Andrea

    2012-01-01

    Summary There is a debate in the literature about the need for Computed Tomagraphy (CT) before removing third molars, even if positive radiographic signs are present. In few cases, the third molar is so close to the inferior alveolar nerve that its extraction might expose patients to the risk of post-operative neuro-sensitive alterations of the skin and the mucosa of the homolateral lower lip and chin. Thus, the injury of the inferior alveolar nerve may represent a serious, though infrequent, neurologic complication in the surgery of the third molars rendering necessary a careful pre-operative evaluation of their anatomical relationship with the inferior alveolar nerve by means of radiographic imaging techniques. This contribution presents two case reports showing positive radiographic signs, which are the hallmarks of a possible close relationship between the inferior alveolar nerve and the third molars. We aim at better defining the relationship between third molars and the mandibular canal using Dental CT Scan, DICOM image acquisition and 3D reconstruction with a dedicated software. By our study we deduce that 3D images are not indispensable, but they can provide a very agreeable assistance in the most complicated cases. PMID:23386934

  14. Finite Element Reconstruction of a Mandibular First Molar

    PubMed Central

    Ehsani, Sara; Mirhashemi, Fatemeh Sadat; Asgary, Saeed

    2013-01-01

    Introduction Mandibular first molar is the most important tooth with complicated morphology. In finite element (FE) studies, investigators usually prefer to model anterior teeth with a simple and single straight root; it makes the results deviate from the actual case. The most complicated and time-consuming step in FE studies is modeling of the desired tooth, thus this study was performed to establish a finite element method (FEM) of reconstructing a mandibular first molar with the greatest precision. Materials and Methods An extracted mandibular first molar was digitized, and then radiographed from different aspects to achieve its outer and inner morphology. The solid model of tooth and root canals were constructed according to this data as well as the anatomy of mandibular first molar described in the literature. Result A three-dimensional model of mandibular first molar was created, giving special consideration to shape and root canal system dimensions. Conclusion This model may constitute a basis for investigating the effect of different clinical situations on mandibular first molars in vitro, especially on its root canal system. The method described here seems feasible and reasonably precise foundation for investigations. PMID:23717327

  15. [Headgear-free molar distalization].

    PubMed

    Manhartsberger, C

    1994-12-01

    The difficulty in treating dentoalveolar class II disharmonies is briefly outlined. An innovative treatment method is presented which makes possible a distalization without the use of headgear. In the treatment method bands are cemented on the first molars, next impressions are made of the upper and lower dental arch, and then the impressions are poured with plaster. Following this the models are mounted in centric relationship in an articulator and the bite is opened 2 mm to 3 mm, so that the molars can be moved without making occlusal contact. The apparatus, an acrylic splint, is constructed in such a fashion as to cover the palatal surfaces from 2nd premolar to 2nd premolar. In addition, the premolars are also covered occlusally and buccally and the canine tips and the incisal edges are covered labially. A headgear tube is attached at the buccal surface in the premolar region of the acrylic splint. This acrylic splint, which is itself retentive, is cemented using glass ionomer cement. Combining this apparatus with a modified Nance Button makes it possible to establish an anchoring segment which is able to retain its position in the face of molar distalization. Molar distalization is then performed using a 0.032 inch stainless steel wire, which is placed between the headgear tube of the acrylic splint and the headgear tube of the band of the first molar. Highly elastic nickel-titanium open coil springs are used as the force elements. PMID:7851830

  16. Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization.

    PubMed

    Negre-Barber, A; Montiel-Company, J M; Boronat-Catalá, M; Catalá-Pizarro, M; Almerich-Silla, J M

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9-86.6) and the negative predictive value 84.7% (80.6-88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9-17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47-0.68). The odds ratio was 18.2 (9.39-35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH. PMID:27558479

  17. Complications after third molar surgery.

    PubMed

    Pitekova, L; Satko, I; Novotnakova, D

    2010-01-01

    The authors describe the incidence of postoperative complications after the surgical removal of third molars, most common postoperative complications and their symptoms as well as risk factors leading to greater incidence of postoperative complications (Ref. 17). Full Text (Free, PDF) www.bmj.sk. PMID:20568422

  18. [Topographic features of lingual nerve and its relationship with other anatomical structures in maxillolingual groove].

    PubMed

    Dyidyikin, S S; Syomkin, V A; Kuzin, A V; Sogacheva, V V

    2016-01-01

    By surgical interventions in maxillolingual groove area one should consider anatomical variations and topography of vessels, glands ducts and lingual nerve to prevent their injury. At the Department of Operative Surgery and Topographic Anatomy of the First Moscow State Medical University named after I.M. Sechenov we carried out anatomical study on cadavers (men and women, n=30).The study revealed topographical features of the lingual nerve and its relationship to other anatomical structures in the maxillolingual groove. It was found out that at the level of the second molar (96%) lingual nerve "crosses" duct of submandibular salivary gland, at the level of the third molar lingual nerve is located under the duct and lateral to it, closer to the inner surface of the body of the mandible. At the level of the first molar lingual nerve is located above and medial to Wharton duct and passes along sublingual-lingual muscles (m.hyoglossus). PMID:26925560

  19. Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

    PubMed Central

    Negre-Barber, A.; Montiel-Company, J. M.; Boronat-Catalá, M.; Catalá-Pizarro, M.; Almerich-Silla, J. M.

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9–86.6) and the negative predictive value 84.7% (80.6–88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9–17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47–0.68). The odds ratio was 18.2 (9.39–35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH. PMID:27558479

  20. Fracture behavior of human molars.

    PubMed

    Keown, Amanda J; Lee, James J-W; Bush, Mark B

    2012-12-01

    Despite the durability of human teeth, which are able to withstand repeated loading while maintaining form and function, they are still susceptible to fracture. We focus here on longitudinal fracture in molar teeth-channel-like cracks that run along the enamel sidewall of the tooth between the gum line (cemento-enamel junction-CEJ) and the occlusal surface. Such fractures can often be painful and necessitate costly restorative work. The following study describes fracture experiments made on molar teeth of humans in which the molars are placed under axial compressive load using a hard indenting plate in order to induce longitudinal cracks in the enamel. Observed damage modes include fractures originating in the occlusal region ('radial-median cracks') and fractures emanating from the margin of the enamel in the region of the CEJ ('margin cracks'), as well as 'spalling' of enamel (the linking of longitudinal cracks). The loading conditions that govern fracture behavior in enamel are reported and observations made of the evolution of fracture as the load is increased. Relatively low loads were required to induce observable crack initiation-approximately 100 N for radial-median cracks and 200 N for margin cracks-both of which are less than the reported maximum biting force on a single molar tooth of several hundred Newtons. Unstable crack growth was observed to take place soon after and occurred at loads lower than those calculated by the current fracture models. Multiple cracks were observed on a single cusp, their interactions influencing crack growth behavior. The majority of the teeth tested in this study were noted to exhibit margin cracks prior to compression testing, which were apparently formed during the functional lifetime of the tooth. Such teeth were still able to withstand additional loading prior to catastrophic fracture, highlighting the remarkable damage containment capabilities of the natural tooth structure. PMID:22956116

  1. Comparison of Primary Molar Crown Dimensions with Stainless Steel Crowns in a Sample of Iranian Children

    PubMed Central

    Afshar, Hossein; Kamali Sabeti, Arghavan; Shahrabi, Mahdi

    2015-01-01

    Background and aims. Due to anatomic variation in tooth anatomy between populations, this study compared the buccolingual (BL) and mesiodistal (MD) dimensions of primary molars with those of stainless steel crowns (SSCs) in anIranian population. Materials and methods. Impressions were taken from both dental arches of children, and casts were poured. Teeth with caries, restoration, hypoplasia or other dental anomalies were excluded. 216 primary molars were selected and divided into 4 groups of 54 each (maxillary and mandibular first and second primary molars). MD/BL dimensions were measured using a digital caliper with 0.01 mm precision on casts and SCCs (3M brand). Data were assessed using paired t-test, post hoc test and ANOVA. P < 0.05 was considered statistically significant. Results. The MD dimension of the lower first molar SSC and the BL dimension of the lower second molar SSC had the least difference with the corresponding values of the respective teeth. The MD dimension of the upper second molar SSC and the BL dimension of the upper first molar SSC had the greatest difference with the corresponding values in the respective teeth. Comparison of the two different brands of SSCs for the upper first molar revealed that both types had significant differences with the teeth in terms of both MD (P = 0.0) and BL (P = 0.0) dimensions. Conclusion. In the studied population, best adaptation was seen in second lower molars and the least adaptationswere seen in first and second upper molars. PMID:26236433

  2. Mandibular lip bumper for molar torque control.

    PubMed

    Celentano, Giuseppe; Longobardi, Annalisa; Cannavale, Rosangela; Perillo, Letizia

    2011-01-01

    Treatment effects of lip bumpers alone include flaring of the mandibular incisors, distalization and uprighting of the mandibular first molars, and buccal expansion of the canines, premolars, and molar. Lip forces are transmitted through this appliance onto the molars. Moreover the lip bumper is able to derotate, expand or constrict, upright and reinforce the anchorage whereas torque control is lacking. Aim of this paper is the presentation of a new type of lip bumper that allows the molar torque control. PMID:21515237

  3. Molar versus as a paradigm clash.

    PubMed Central

    Baum, W M

    2001-01-01

    The molar view of behavior arose in response to the demonstrated inadequacy of explanations based on contiguity. Although Dinsmoor's (2001) modifications to two-factor theory render it irrefutable, a more basic criticism arises when we see that the molar and molecular views differ paradigmatically. The molar view has proven more productive. PMID:11453623

  4. [Distalization of the upper second molar: biomechanics].

    PubMed

    Castaldo, A

    1991-01-01

    The Author shows a system to dystalize the second upper molars and, if necessary, the third upper molars. This system, easy to be adapted, is made up by a palatal bar inserted between the first upper molars, by a sectional and a 100 grams precalibrated open Sentalloy coil spring used as an active force. PMID:1784296

  5. Reference Man anatomical model

    SciTech Connect

    Cristy, M.

    1994-10-01

    The 70-kg Standard Man or Reference Man has been used in physiological models since at least the 1920s to represent adult males. It came into use in radiation protection in the late 1940s and was developed extensively during the 1950s and used by the International Commission on Radiological Protection (ICRP) in its Publication 2 in 1959. The current Reference Man for Purposes of Radiation Protection is a monumental book published in 1975 by the ICRP as ICRP Publication 23. It has a wealth of information useful for radiation dosimetry, including anatomical and physiological data, gross and elemental composition of the body and organs and tissues of the body. The anatomical data includes specified reference values for an adult male and an adult female. Other reference values are primarily for the adult male. The anatomical data include much data on fetuses and children, although reference values are not established. There is an ICRP task group currently working on revising selected parts of the Reference Man document.

  6. Rat molar teeth as a study model for direct pulp capping research in dentistry.

    PubMed

    Dammaschke, Till

    2010-01-01

    The aim of this review is to evaluate the suitability of rat molar teeth in preclinical evaluation of medical devices for direct pulp capping. The ISO standard 7405 states clearly that only non-rodent mammals are suitable species for animal research in dentistry. Furthermore, without clear justification a considerable number of researchers previously rejected results of animal experiments concerning preclinical evaluation of the biocompatibility of dental materials undertaken in rat molar teeth. However, in the past 50 years about 70 studies have been published using rat molar teeth in order to evaluate direct pulp capping, pulpotomies and tissue reactions after pulp exposure. Numerous studies showed that the healing of rat molar pulp tissue after direct pulp capping is histologically comparable with humans and other animal species pulp tissue. Rat molar teeth, including pulp tissue, can be seen anatomically, histologically, biologically, and physiologically as miniature human molar teeth. Hence, the essential biological reactions of the pulp tissue and the interaction during the different stages of wound healing of rat molar teeth are comparable with that of other mammals. Rat molar teeth are a valid study model in order to provide valuable data concerning pulp tissue reaction after direct pulp capping and related questions in dentistry. Therefore, the use of rats may significantly reduce the number of currently used higher animals in research. Tests in higher developed animals should be limited to experiments which clarify inconsistent results. However, some technical difficulties, like the small size of rat molar teeth must be dealt with before undertaking any research. PMID:19854755

  7. An in vitro assessment of type, position and incidence of isthmus in human permanent molars

    PubMed Central

    de LIMA, Fernando José Camello; MONTAGNER, Francisco; JACINTO, Rogério Castilho; AMBROSANO, Glaucia Maria Bovi; GOMES, Brenda Paula Figueiredo de Almeida

    2014-01-01

    Root canal anatomical complexities, such as isthmus, may limit the action of the endodontic instruments, irrigant solutions and intracanal medications, leading to endodontic treatment failure. Objectives This in vitro study assessed the type, position and incidence of isthmus in human permanent molars. Material and Methods One hundred and twenty eight upper and lower first and second permanent molars were analyzed. The roots were embedded in transparent resin, and then split at different distances from the apex (1.0-2.5-4.0-5.5-7.0 mm). Following the sample examination in stereomicroscope, the data were submitted to chi-square statistical test at a 5% significance level. Results The highest isthmus incidence was at 7.0 mm from the root apex in all samples, except the distal root of lower molars (at 5.5 mm). In upper and lower molars, type V (complete isthmus with a continuous opening between the two main root canals) was the most common classification of isthmus (28.8%). In the mesial root of first and second mandibular molars, type IV had the highest incidence (36% and 23.9%, respectively). Conclusion It was concluded that isthmus was widely found in flat roots, with a low percentage in areas close to the apex. In upper and lower molars, these structures were most frequently found at 7 mm from the apex. PMID:25141198

  8. Endodontic Treatment of Hypertaurodontic Mandibular Molar Using Reciprocating Single-file System: A Case Report.

    PubMed

    C do Nascimento, Adriano; A F Marques, André; C Sponchiado-Júnior, Emílio; F R Garcia, Lucas; M A de Carvalho, Fredson

    2016-01-01

    Taurodontism is a developmental tooth disorder characterized by lack of constriction in the cementoenamel junction and consequent vertical stretch of the pulp chamber, accompanied by apical displacement of the pulpal floor. The endodontic treatment of teeth with this type of morpho-anatomical anomaly is challenging. The purpose of this article is to report the successful endodontic treatment of a hypertaurodontic mandibular molar using a reciprocating single-file system. PMID:27320297

  9. Value of Computed Tomography (CT) in Imaging the Morbidity of Submerged Molars: A Case Report

    PubMed Central

    Kırzıoḡlu, Zuhal; Karayılmaz, Hüseyin; Baykal, Bahattin

    2007-01-01

    Submerged primary molars can be difficult to manage due to the developing dentition. Rarely in some severe cases, may the surgical interventions be required while ensuring the vital structures are protected. Therefore these cases require sophisticated imaging techniques in order to locate the vital structures. In this case report, a 17 year old girl who had a retained and submerged deciduous molar which caused impaction of the second premolar and tipping of the first molar was presented. In addition, value of computed tomography (CT) for locating the vital anatomic structures was discussed. In our case, CT has been supplied effective information about localization of the vital structures and amount of bone volume during the diagnosis and treatment planning period in addition to the routine dental radiographies. PMID:19212475

  10. Endodontic management of mandibular first molar with seven canals using cone-beam computed tomography.

    PubMed

    Banode, Ankur Mahesh; Gade, Vandana; Patil, Sanjay; Gade, Jaykumar

    2016-01-01

    The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and clinically challenging. Successful endodontic therapy thus depends on the clinician's ability to anticipate and look for these aberrant variations. A mandibular first molar with seven canals represents a rare anatomical variant, particularly when four canals are found in distal root. Based on in vitro studies, its incidence is reported to be between 0.2% and 3%. With the advent of cone-beam computed tomography (CBCT) as an adjunctive diagnostic aid, the determination of root canal anatomy in teeth with complex canal configurations has become more precise. The present case report discusses successful nonsurgical management of radix entomolaris along with middle mesial canal and middle distal canal in mandibular first molar with seven canals (four canals in distal and three in mesial) employing CBCT as an adjunctive diagnostic aid to conventional radiography. PMID:27307680

  11. Endodontic management of mandibular first molar with seven canals using cone-beam computed tomography

    PubMed Central

    Banode, Ankur Mahesh; Gade, Vandana; Patil, Sanjay; Gade, Jaykumar

    2016-01-01

    The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and clinically challenging. Successful endodontic therapy thus depends on the clinician's ability to anticipate and look for these aberrant variations. A mandibular first molar with seven canals represents a rare anatomical variant, particularly when four canals are found in distal root. Based on in vitro studies, its incidence is reported to be between 0.2% and 3%. With the advent of cone-beam computed tomography (CBCT) as an adjunctive diagnostic aid, the determination of root canal anatomy in teeth with complex canal configurations has become more precise. The present case report discusses successful nonsurgical management of radix entomolaris along with middle mesial canal and middle distal canal in mandibular first molar with seven canals (four canals in distal and three in mesial) employing CBCT as an adjunctive diagnostic aid to conventional radiography. PMID:27307680

  12. Occipital neuralgia: anatomic considerations.

    PubMed

    Cesmebasi, Alper; Muhleman, Mitchel A; Hulsberg, Paul; Gielecki, Jerzy; Matusz, Petru; Tubbs, R Shane; Loukas, Marios

    2015-01-01

    Occipital neuralgia is a debilitating disorder first described in 1821 as recurrent headaches localized in the occipital region. Other symptoms that have been associated with this condition include paroxysmal burning and aching pain in the distribution of the greater, lesser, or third occipital nerves. Several etiologies have been identified in the cause of occipital neuralgia and include, but are not limited to, trauma, fibrositis, myositis, fracture of the atlas, and compression of the C-2 nerve root, C1-2 arthrosis syndrome, atlantoaxial lateral mass osteoarthritis, hypertrophic cervical pachymeningitis, cervical cord tumor, Chiari malformation, and neurosyphilis. The management of occipital neuralgia can include conservative approaches and/or surgical interventions. Occipital neuralgia is a multifactorial problem where multiple anatomic areas/structures may be involved with this pathology. A review of these etiologies may provide guidance in better understanding occipital neuralgia. PMID:25244129

  13. Retromolar foramen: an anatomical study with clinical considerations.

    PubMed

    Gamieldien, M Y; Van Schoor, A

    2016-09-01

    The retromolar canal and foramen, an anatomical variation in the mandibular retromolar area, houses and transmits neurovascular elements that may innervate the mandibular third molar and associated tissues. These structures have been implicated in local anaesthetic failure, loss of sensation in the normal distribution of the buccal nerve, and local haemorrhage during surgery. Examination of 885 dry mandibles showed that 70 had a retromolar foramen (8%). There were no significant differences between groups according to age, sex, or ancestry. The mean (SD) distance from molar to retromolar foramen was 16.8 (5.6) mm for the mandibular second molar and 10.5 (3.8) mm for the mandibular third molar. The link between these structures and failure of local anaesthesia seems tenuous at best. Bleeding may not represent a serious complication. Although there may be a possibility of perineural spread of infective and invasive pathology, we know of no reported cases. The only clear evidence of complications associated with a confirmed retromolar foramen seems to be loss of sensation in the normal distribution of the buccal nerve. Even though the retromolar foramen does not seem to be of great clinical importance, it could be a source of anxiety for the inexperienced practitioner. PMID:27354332

  14. Molar volumes and densities of minerals

    USGS Publications Warehouse

    Robie, Richard A.; Bethke, Philip M.

    1962-01-01

    These tables present critically chosen "best values" for the density and molar volume of selected mineral compounds. No attempt was made to be all-inclusive; rather we have tried to present data for chemically and physically well-defined phases for which the molar volume and/or density was knovvn to the order of 0. 2 percent.

  15. General technique of third molar removal.

    PubMed

    Farish, Sam E; Bouloux, Gary F

    2007-02-01

    The most commonly performed surgical procedure in most oral and maxillofacial surgery practices is the removal of impacted third molars. Extensive training, skill, and experience allow this procedure to be performed in an atraumatic fashion with local anesthesia, sedation, or general anesthesia. The decision to remove symptomatic third molars is not usually difficult, but the decision to remove asymptomatic third molars is sometimes less clear and requires clinical experience. A wide body of literature (discussed elsewhere in this issue) attempts to establish clinical practice guidelines for dealing with impacted teeth. Data is beginning to accumulate from third molar studies, which hopefully will provide surgeons and their patients with evidence-based guidelines regarding elective third molar surgery. PMID:18088862

  16. Expressly fabricated molar tube bases: enhanced adhesion.

    PubMed

    Sharma, Tarun; Phull, Tarun Singh; Rana, Tarun; Kumar, Varun

    2014-06-01

    Clinicians, Orthodontists and their patients' parents often expect the best results in the shortest time span possible. Orthodontic bonding of molar tubes has been an acceptable risk in a modern era of refined biomaterials and instrumentation. Although many orthodontists still prefer banding to bonding, it is the failure rate of the tubes on molars which accounts to an impedance in molar bonding. One of the reasons for molar attachment failures is attributed to improper adaptation of the buccal tube base with or without increased thickness of composite. Merits of banding the second molars especially when these are the terminal teeth for anchorage have been overemphasized in the literature. The present article presents a simple and relatively less time consuming technique of preparing molar tubes to be bonded on tooth surfaces which may be quite difficult to isolate especially for bonding, for example, mandibular second molars. The increased surface area of the composite scaffold helps not only in enhanced bond strength but also serves to reduce the incidence of plaque accumulation given the dexterity of invitro preparation. The removal of the occlusal part of the molar tube scaffold helps in prevention of open / raised bite tendencies. The present innovation, therefore, is not merely serendipity but a structured technique to overcome a common dilemma for the clinical orthodontist. The present dictum of banding being superior to molar tube bonding may prove to be futile with trendsetting molar attachments. It is also an established fact that bonding proves to be a lesser expensive modality when compared to banding procedures. PMID:25121070

  17. Dietary inference from upper and lower molar morphology in platyrrhine primates.

    PubMed

    Allen, Kari L; Cooke, Siobhán B; Gonzales, Lauren A; Kay, Richard F

    2015-01-01

    The correlation between diet and dental topography is of importance to paleontologists seeking to diagnose ecological adaptations in extinct taxa. Although the subject is well represented in the literature, few studies directly compare methods or evaluate dietary signals conveyed by both upper and lower molars. Here, we address this gap in our knowledge by comparing the efficacy of three measures of functional morphology for classifying an ecologically diverse sample of thirteen medium- to large-bodied platyrrhines by diet category (e.g., folivore, frugivore, hard object feeder). We used Shearing Quotient (SQ), an index derived from linear measurements of molar cutting edges and two indices of crown surface topography, Occlusal Relief (OR) and Relief Index (RFI). Using SQ, OR, and RFI, individuals were then classified by dietary category using Discriminate Function Analysis. Both upper and lower molar variables produce high classification rates in assigning individuals to diet categories, but lower molars are consistently more successful. SQs yield the highest classification rates. RFI and OR generally perform above chance. Upper molar RFI has a success rate below the level of chance. Adding molar length enhances the discriminatory power for all variables. We conclude that upper molar SQs are useful for dietary reconstruction, especially when combined with body size information. Additionally, we find that among our sample of platyrrhines, SQ remains the strongest predictor of diet, while RFI is less useful at signaling dietary differences in absence of body size information. The study demonstrates new ways for inferring the diets of extinct platyrrhine primates when both upper and lower molars are available, or, for taxa known only from upper molars. The techniques are useful in reconstructing diet in stem representatives of anthropoid clade, who share key aspects of molar morphology with extant platyrrhines. PMID:25738266

  18. Dietary Inference from Upper and Lower Molar Morphology in Platyrrhine Primates

    PubMed Central

    Allen, Kari L.; Cooke, Siobhán B.; Gonzales, Lauren A.; Kay, Richard F.

    2015-01-01

    The correlation between diet and dental topography is of importance to paleontologists seeking to diagnose ecological adaptations in extinct taxa. Although the subject is well represented in the literature, few studies directly compare methods or evaluate dietary signals conveyed by both upper and lower molars. Here, we address this gap in our knowledge by comparing the efficacy of three measures of functional morphology for classifying an ecologically diverse sample of thirteen medium- to large-bodied platyrrhines by diet category (e.g., folivore, frugivore, hard object feeder). We used Shearing Quotient (SQ), an index derived from linear measurements of molar cutting edges and two indices of crown surface topography, Occlusal Relief (OR) and Relief Index (RFI). Using SQ, OR, and RFI, individuals were then classified by dietary category using Discriminate Function Analysis. Both upper and lower molar variables produce high classification rates in assigning individuals to diet categories, but lower molars are consistently more successful. SQs yield the highest classification rates. RFI and OR generally perform above chance. Upper molar RFI has a success rate below the level of chance. Adding molar length enhances the discriminatory power for all variables. We conclude that upper molar SQs are useful for dietary reconstruction, especially when combined with body size information. Additionally, we find that among our sample of platyrrhines, SQ remains the strongest predictor of diet, while RFI is less useful at signaling dietary differences in absence of body size information. The study demonstrates new ways for inferring the diets of extinct platyrrhine primates when both upper and lower molars are available, or, for taxa known only from upper molars. The techniques are useful in reconstructing diet in stem representatives of anthropoid clade, who share key aspects of molar morphology with extant platyrrhines. PMID:25738266

  19. [Anatomical rationale for lingual nerve injury prevention during mandibular block].

    PubMed

    Semkin, V A; Dydikin, S S; Kuzin, A V; Sogacheva, V V

    2015-01-01

    The topographic and anatomical study of lingual nerve structural features was done. It was revealed that during mandibular anesthesia possible lingual nerve injury can occur if puncture needle is lower than 1 cm. of molars occlusal surface level. The position of the lingual nerve varies withmandible movements. At the maximum open mouth lingual nerve is not mobile and is pressed against the inner surface of the mandibular ramus by the medial pterygoid muscle and the temporal muscle tendon. When closing the mouth to 1.25±0.2 cmfrom the physiological maximum, lingual nerve is displaced posteriorly from the internal oblique line of the mandible and gets mobile. On the basis of topographic and anatomic features of the lingual nervestructure the authors recommend the re-do of inferior alveolar nerve block, a semi-closed mouth position or the use the "high block techniques" (Torus anesthesia, Gow-Gates, Vazirani-Akinozi). PMID:26271698

  20. The complexity of anatomical systems

    PubMed Central

    Grizzi, Fabio; Chiriva-Internati, Maurizio

    2005-01-01

    Background The conception of anatomical entities as a hierarchy of infinitely graduated forms and the increase in the number of observed anatomical sub-entities and structural variables has generated a growing complexity, thus highlighting new properties of organised biological matter. Results (1) Complexity is so pervasive in the anatomical world that it has come to be considered as a primary characteristic of anatomical systems. (2) Anatomical entities, when viewed at microscopic as well as macroscopic level of observation, show a different degree of complexity. (3) Complexity can reside in the structure of the anatomical system (having many diverse parts with varying interactions or an intricate architecture) or in its behaviour. Often complexity in structure and behaviour go together. (4) Complex systems admit many descriptions (ways of looking at the system) each of which is only partially true. Each way of looking at a complex system requires its own description, its own mode of analysis and its own breaking down of the system in different parts; (5) Almost all the anatomical entities display hierarchical forms: their component structures at different spatial scales or their process at different time scales are related to each other. Conclusion The need to find a new way of observing and measuring anatomical entities, and objectively quantifying their different structural changes, prompted us to investigate the non-Euclidean geometries and the theories of complexity, and to apply their concepts to human anatomy. This attempt has led us to reflect upon the complex significance of the shape of an observed anatomical entity. Its changes have been defined in relation to variations in its status: from a normal (i.e. natural) to a pathological or altered state introducing the concepts of kinematics and dynamics of anatomical forms, speed of their changes, and that of scale of their observation. PMID:16029490

  1. Maxillary second molar impaction in the adjacent ectopic third molar: Report of five rare cases.

    PubMed

    Souki, Bernardo Q; Cheib, Paula L; de Brito, Gabriela M; Pinto, Larissa S M C

    2015-01-01

    Maxillary second molar impaction in the adjacent ectopic third molar is a rare condition that practitioners might face in the field of pediatric dentistry and orthodontics. The early diagnosis and extraction of the adjacent ectopic third molar have been advocated, and prior research has reported a high rate of spontaneous eruption following third molar removal. However, some challenges in the daily practice are that the early diagnosis of this type of tooth impaction is difficult with conventional radiographic examination, and sometimes the early surgical removal of the maxillary third molar must be postponed because of the risks of damaging the second molar. The objective of this study is to report a case series of five young patients with maxillary second molar impaction and to discuss the difficulty of early diagnosis with the conventional radiographic examination, and unpredictability of self-correction. PMID:26321848

  2. Tracking in anatomic pathology.

    PubMed

    Pantanowitz, Liron; Mackinnon, Alexander C; Sinard, John H

    2013-12-01

    Bar code-based tracking solutions, long present in clinical pathology laboratories, have recently made an appearance in anatomic pathology (AP) laboratories. Tracking of AP "assets" (specimens, blocks, slides) can enhance laboratory efficiency, promote patient safety, and improve patient care. Routing of excess clinical material into research laboratories and biorepositories are other avenues that can benefit from tracking of AP assets. Implementing tracking is not as simple as installing software and turning it on. Not all tracking solutions are alike. Careful analysis of laboratory workflow is needed before implementing tracking to assure that this solution will meet the needs of the laboratory. Such analysis will likely uncover practices that may need to be modified before a tracking system can be deployed. Costs that go beyond simply that of purchasing software will be incurred and need to be considered in the budgeting process. Finally, people, not technology, are the key to assuring quality. Tracking will require significant changes in workflow and an overall change in the culture of the laboratory. Preparation, training, buy-in, and accountability of the people involved are crucial to the success of this process. This article reviews the benefits, available technology, underlying principles, and implementation of tracking solutions for the AP and research laboratory. PMID:23634908

  3. Proximity of the mandibular molar root apex from the buccal bone surface: a cone-beam computed tomographic study

    PubMed Central

    Kim, Dokyung; Jin, Myoung-Uk

    2016-01-01

    Objectives The purpose of this study was to evaluate the proximity of the mandibular molar apex to the buccal bone surface in order to provide anatomic information for apical surgery. Materials and Methods Cone-beam computed tomography (CBCT) images of 127 mandibular first molars and 153 mandibular second molars were analyzed from 160 patients' records. The distance was measured from the buccal bone surface to the root apex and the apical 3.0 mm on the cross-sectional view of CBCT. Results The second molar apex and apical 3 mm were located significantly deeper relative to the buccal bone surface compared with the first molar (p < 0.01). For the mandibular second molars, the distance from the buccal bone surface to the root apex was significantly shorter in patients over 70 years of age (p < 0.05). Furthermore, this distance was significantly shorter when the first molar was missing compared to nonmissing cases (p < 0.05). For the mandibular first molars, the distance to the distal root apex of one distal-rooted tooth was significantly greater than the distance to the disto-buccal root apex (p < 0.01). In mandibular second molar, the distance to the apex of C-shaped roots was significantly greater than the distance to the mesial root apex of non-C-shaped roots (p < 0.01). Conclusions For apical surgery in mandibular molars, the distance from the buccal bone surface to the apex and apical 3 mm is significantly affected by the location, patient age, an adjacent missing anterior tooth, and root configuration. PMID:27508159

  4. Unilateral Molar Distalization: A Nonextraction Therapy

    PubMed Central

    Prasad, M. Bhanu; Sreevalli, S.

    2012-01-01

    In the recent years, nonextraction treatment approaches and noncompliance therapies have become more popular in the correction of space discrepancies. One of the conventional approaches for space gaining in the arches without patient compliance is done by using certain extra oral appliances or intraoral appliance. The greatest advantage of certain appliances like fixed functional and molar distalization appliances is that they minimize the dependence on patient cooperation. Molar distalization appliances like pendulum appliance which distalizes the molar rapidly without the need of head gear can be used in patients as a unilateral space gaining procedure due to buccal segment crowding. PMID:23320203

  5. The anatomical school of Padua.

    PubMed

    Porzionato, Andrea; Macchi, Veronica; Stecco, Carla; Parenti, Anna; De Caro, Raffaele

    2012-06-01

    The University of Padua is one of the most ancient in the world, being founded in 1222, and the most important anatomists of the XVI, XVII, and XVIII centuries studied and taught here. Probably, the first professor of anatomy and surgery was Bruno da Longobucco (c. 1200-c. 1286), who had previously studied at the Salerno School of Medicine. While professor in Padua, Andreas Vesalius (1514-1564) published De Humani Corporis Fabrica (1543), which is considered as the birth of the modern anatomy. Following professors were Realdo Colombo (c. 1516-1559), Gabriel Fallopius (1523-1562), Hieronymus Fabricius ab Aquapendente (1533-1619), Iulius Casserius (1552-1616), Johann Wesling (1598-1649), and Johann Georg Wirsung (1589-1643). Many other foreign scholars studied in the University of Padua, such as Thomas Linacre (c. 1460-1524), the founder of the Royal College of Physicians, Werner Rolfinck (1599-1673), and Olof Rudbeck (1630-1702), who created anatomical theatres in Germany and Sweden, respectively, on the basis of the Paduan model. The anatomy of the XVII century characteristically widened the scope of its enquiry to function, as in the Exercitatio Anatomica De Motu Cordis et Sanguinis in Animalibus (1628) by William Harvey (1578-1657). Further evolution was then given by the anatomy in the XVIII century, which tried to correlate alterations of structure with clinical symptoms. The most important anatomist of this century is Giovanni Battista Morgagni (1682-1771), whose masterpiece De Sedibus et Causis Morborum per Anatomen Indagatis (1761) is a landmark contribution that is viewed as the beginning of modern pathologic anatomy. This year falls the 300th anniversary of Morgagni's inaugural lecture on medical education, Nova Institutionum Medicarum Idea (1712), which is still relevant in its effort to stress the importance of a deep knowledge of all the preclinical and clinical aspects of medical science. PMID:22581496

  6. Evolution of the anatomical theatre in Padova.

    PubMed

    Macchi, Veronica; Porzionato, Andrea; Stecco, Carla; De Caro, Raffaele

    2014-01-01

    The anatomical theatre played a pivotal role in the evolution of medical education, allowing students to directly observe and participate in the process of dissection. Due to the increase of training programs in clinical anatomy, the Institute of Human Anatomy at the University of Padova has renovated its dissecting room. The main guidelines in planning a new anatomical theatre included: (1), the placement of the teacher and students on the same level in a horizontal anatomical theatre where it is possible to see (theatre) and to perform (dissecting room); (2), in the past, dissection activities were concentrated at the center of the theatre, while in the new anatomical theatre, such activities have been moved to the periphery through projection on surrounding screens-thus, students occupy the center of the theatre between the demonstration table, where the dissection can be seen in real time, and the wall screens, where particular aspects are magnified; (3), three groups of tables are placed with one in front with two lateral flanking tables in regards to the demonstration table, in a semicircular arrangement, and not attached to the floor, which makes the room multifunctional for surgical education, medical students and physician's continued professional development courses; (4), a learning station to introduce the students to the subject of the laboratory; (5), cooperation between anatomists and architects in order to combine the practical needs of a dissection laboratory with new technologies; (6), involvement of the students, representing the clients' needs; and (7), creation of a dissecting room of wide measurements with large windows, since a well-illuminated space could reduce the potentially negative psychological impact of the dissection laboratory on student morale. PMID:24706523

  7. Primate molar crown formation times and life history evolution revisited.

    PubMed

    Macho, G A

    2001-12-01

    Comparative studies have convincingly demonstrated that the pattern and timing of tooth emergence are highly correlated with life-history variables and brain size. Conversely, a firm relationship between molar formation time and life-history variables has not yet been established. It seems counterintuitive that one aspect of dental development should be correlated with life-history variables, whereas the other should not. In order to shed light on this apparent discrepancy this study analyzed all data on primate molar crown formations available in the published literature in relation to life-history variables, brain size, and female body mass. Crown formation times were found to be particularly highly correlated with both female body mass and brain size. Species that depart from the overall brain/body allometry by being relatively large-bodied, e.g., Gorilla gorilla and later Theropithecus oswaldi, also have shorter molar crown formation times than expected. The reverse is not found for species that depart from the overall brain/body allometry due to their larger brains, i.e., Homo sapiens. This finding is interpreted within an evolutionary and ecological framework. Specifically, by focusing on ecological commonalities, a scenario is proposed which may allow predictions to be made about the evolutionary history of other extinct primates also. If confirmed in future studies, crown formation time may again become a powerful tool in evolutionary enquiry. PMID:11748692

  8. Morphometric evaluation and planning of anticurvature filing in roots of maxillary and mandibular molars.

    PubMed

    Oliveira, Maria Antonieta Veloso Carvalho; Venâncio, Jessyca Figueira; Raposo, Luís Henrique Araújo; Barbosa Júnior, Nelson; Biffi, João Carlos Gabrielli

    2015-01-01

    This study aimed to guide the planning of anticurvature filing using pre-determined anatomical points on teeth to establish directions for proper implementation of the technique. Two hundred digital periapical radiographs of human molar teeth were selected and divided into two groups (n = 100): MX (maxillary) and MD (mandibular) molars. Mesiobuccal roots were considered for the MX group and mesial roots for the MD group. Pre-determined anatomical points required for planning the anticurvature filing on the root canal path were located, and the distances between these points obtained. The anticurvature filing was simulated in two different protocols for each group, and the region of dentin removal and the remaining dentin thickness were measured in the safety and danger zones of the root canals. Statistical analysis was carried out at a significance level of 5%. The distances between the anatomical points and the thickness of remaining dentin showed significant differences when the two groups were compared (p < 0.001). No significant differences were found between the two experimental groups regarding the area of dentin removal at the root region, but differences were detected in comparison with dentin removal at the crown (p < 0.001). In terms of wear produced after simulation of both anticurvature filing protocols, significant differences were verified for all regions, except for the dentin remaining at the danger zone. The radiographic location of anatomical points allows for planning and implementation of controlled and efficient anticurvature filing and can be performed in the same manner for maxillary and mandibular molars. PMID:25466326

  9. Molars and incisors: show your microarray IDs

    PubMed Central

    2013-01-01

    Background One of the key questions in developmental biology is how, from a relatively small number of conserved signaling pathways, is it possible to generate organs displaying a wide range of shapes, tissue organization, and function. The dentition and its distinct specific tooth types represent a valuable system to address the issues of differential molecular signatures. To identify such signatures, we performed a comparative transcriptomic analysis of developing murine lower incisors, mandibular molars and maxillary molars at the developmental cap stage (E14.5). Results 231 genes were identified as being differentially expressed between mandibular incisors and molars, with a fold change higher than 2 and a false discovery rate lower than 0.1, whereas only 96 genes were discovered as being differentially expressed between mandibular and maxillary molars. Numerous genes belonging to specific signaling pathways (the Hedgehog, Notch, Wnt, FGF, TGFβ/BMP, and retinoic acid pathways), and/or to the homeobox gene superfamily, were also uncovered when a less stringent fold change threshold was used. Differential expressions for 10 out of 12 (mandibular incisors versus molars) and 9 out of 10 selected genes were confirmed by quantitative reverse transcription-PCR (qRT-PCR). A bioinformatics tool (Ingenuity Pathway Analysis) used to analyze biological functions and pathways on the group of incisor versus molar differentially expressed genes revealed that 143 genes belonged to 9 networks with intermolecular connections. Networks with the highest significance scores were centered on the TNF/NFκB complex and the ERK1/2 kinases. Two networks ERK1/2 kinases and tretinoin were involved in differential molar morphogenesis. Conclusion These data allowed us to build several regulatory networks that may distinguish incisor versus molar identity, and may be useful for further investigations of these tooth-specific ontogenetic programs. These programs may be dysregulated in

  10. Anatomic Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Murawski, Christopher D.; Wolf, Megan R.; Araki, Daisuke; Muller, Bart; Tashman, Scott

    2013-01-01

    Anatomic anterior cruciate ligament (ACL) reconstruction is common procedure performed by orthopedic surgeons, particularly in association with sports-related injuries. Whereas traditional reconstruction techniques used a single bundle graft that was typically placed in a non-anatomic position, a renewed interest in anatomy has facilitated the popularization of anatomic reconstruction techniques. Recently, a focus has been placed on individualizing ACL surgery based on each patient’s native anatomical characteristics (e.g., insertion site size, notch size, and shape), thereby dictating the ultimate procedure of choice. As subjective outcome measurements have demonstrated varying outcomes with respect to single- versus double-bundle ACL reconstruction, investigators have turned to more objective techniques, such as in vivo kinematics, as a means of evaluating joint motion and cartilage contact mechanics. Further investigation in this area may yield important information with regard to the potential progression to osteoarthritis after ACL reconstruction, including factors affecting or preventing it. PMID:26069663

  11. Anatomically Shaped Tooth and Periodontal Regeneration by Cell Homing

    PubMed Central

    Kim, K.; Lee, C.H.; Kim, B.K.; Mao, J.J.

    2010-01-01

    Tooth regeneration by cell delivery encounters translational hurdles. We hypothesized that anatomically correct teeth can regenerate in scaffolds without cell transplantation. Novel, anatomically shaped human molar scaffolds and rat incisor scaffolds were fabricated by 3D bioprinting from a hybrid of poly-ε-caprolactone and hydroxyapatite with 200-µm-diameter interconnecting microchannels. In each of 22 rats, an incisor scaffold was implanted orthotopically following mandibular incisor extraction, whereas a human molar scaffold was implanted ectopically into the dorsum. Stromal-derived factor-1 (SDF1) and bone morphogenetic protein-7 (BMP7) were delivered in scaffold microchannels. After 9 weeks, a putative periodontal ligament and new bone regenerated at the interface of rat incisor scaffold with native alveolar bone. SDF1 and BMP7 delivery not only recruited significantly more endogenous cells, but also elaborated greater angiogenesis than growth-factor-free control scaffolds. Regeneration of tooth-like structures and periodontal integration by cell homing provide an alternative to cell delivery, and may accelerate clinical applications. PMID:20448245

  12. Maxillary molar distalization with first class appliance

    PubMed Central

    Ramesh, Namitha; Palukunnu, Biswas; Ravindran, Nidhi; Nair, Preeti P

    2014-01-01

    Non-extraction treatment has gained popularity for corrections of mild-to-moderate class II malocclusion over the past few decades. The distalization of maxillary molars is of significant value for treatment of cases with minimal arch discrepancy and mild class II molar relation associated with a normal mandibular arch and acceptable profile. This paper describes our experience with a 16-year-old female patient who reported with irregularly placed upper front teeth and unpleasant smile. The patient was diagnosed to have angles class II malocclusion with moderate maxillary anterior crowding, deep bite of 4 mm on a skeletal class II base with an orthognathic maxilla and retrognathic mandible and normal growth pattern. She presented an ideal profile and so molar distalization was planned with the first-class appliance. Molars were distalised by 8 mm on the right and left quadrants and class I molar relation achieved within 4 months. The space gained was utilised effectively to align the arch and establish a class I molar and canine relation. PMID:24577171

  13. A veterinary digital anatomical database.

    PubMed Central

    Snell, J. R.; Green, R.; Stott, G.; Van Baerle, S.

    1991-01-01

    This paper describes the Veterinary Digital Anatomical Database Project. The purpose of the project is to investigate the construction and use of digitally stored anatomical models. We will be discussing the overall project goals and the results to date. Digital anatomical models are 3 dimensional, solid model representations of normal anatomy. The digital representations are electronically stored and can be manipulated and displayed on a computer graphics workstation. A digital database of anatomical structures can be used in conjunction with gross dissection in teaching normal anatomy to first year students in the professional curriculum. The computer model gives students the opportunity to "discover" relationships between anatomical structures that may have been destroyed or may not be obvious in the gross dissection. By using a digital database, the student will have the ability to view and manipulate anatomical structures in ways that are not available through interactive video disk (IVD). IVD constrains the student to preselected views and sections stored on the disk. Images Figure 1 PMID:1807707

  14. Efficiency of a pendulum appliance for molar distalization related to second and third molar eruption stage.

    PubMed

    Kinzinger, Gero S M; Fritz, Ulrike B; Sander, Franz-Günter; Diedrich, Peter R

    2004-01-01

    A modified pendulum appliance, including a distal screw and special preactivated pendulum springs (built-in straightening activation and toe-in bending), was used for bilateral maxillary molar distalization in 36 adolescent patients in various stages of the molar dentition. The patients were divided into 3 groups (PG 1-3) according to the stage of eruption of their second and third molars. In PG 1 (18 patients), eruption of the second molars had either not yet taken place or was not complete. In PG 2 (15 patients), the second molars had already developed as far as the occlusal plane, with the third molars at the budding stage. In PG 3 (3 patients), germectomy of the wisdom teeth had been carried out, and the first and second molars on both sides had completely erupted. Analysis of cephalograms to identify any changes in the sagittal plane showed that, in the direction of distalization, a tooth bud acts on the mesial neighboring tooth like a fulcrum, and that tipping of the first molars in patients in whom the second molar was still at the budding stage was thus greater. In patients whose second molars had erupted completely, the degree of tipping was greater again when a third molar bud was located in the direction of movement. After previously completed germectomy of the wisdom teeth, almost exclusively bodily distalization of both molars is possible, even without bands being applied to the second molars. However, if the first and second molars are distalized simultaneously with a pendulum appliance, the duration of therapy will be longer, greater forces will have to be applied, and more anchorage will be lost. Statistical analysis of the results of dental-angular measurements showed significant differences in the degree of molar tipping and reciprocal incisor protrusion. The degree of distal tipping of first molars was less in patients with erupted second molars (PG 2 and PG 3) than in those whose second molars were not yet erupted (PG 1). For instance, the

  15. Classification of impacted mandibular third molars on cone-beam CT images

    PubMed Central

    Maglione, Michele; Bazzocchi, Gabriele

    2015-01-01

    Background Neurological involvement is a serious complication associated to the surgical removal of impacted mandibular third molars and the radiological investigation is the first mandatory step to assess the risk of a possible post-operative injury to the inferior alveolar nerve (IAN). The aim of this study was to introduce a new radiological classification that could be normally used in clinical practice to assess the relationship between an impacted third molar and mandibular canal on cone beam CT (CBCT) images. Material and Methods CBCT images of 80 patients (133 mandibular third molars) were independently studied by three members of the surgical team to draw a classification that could describe all the possible relationships between third molar and IAN on the cross-sectional images. Subsequently, the study population was subdivided according to this classification. The SPSS software, version 15.0 (SPSS® Inc., Chicago, Illinois, USA) was used for the statistical analysis. Results Eight different classes were proposed (classes 0-7) and six of them (classes 1-6) were subdivided in two subtypes (subtypes A-B). The distribution of classes showed a prevalence of buccal or apical course of the mandibular canal followed by lingual position and inter-radicular one. No differences have resulted in terms of anatomic relationship between males and females apart from a higher risk of real contact without corticalization of the canal when the IAN had a lingual course for female group. Younger patients showed an increased rate of direct contact with a reduced calibre of the canal and/or without corticalization. Conclusions The use of this classification could be a valid support in clinical practice to obtain a common language among operators in order to define the possible relationships between an impacted third molar and the mandibular canal on CBCT images. Key words:CBCT, classification, inferior alveolar nerve, third molars. PMID:26155337

  16. Anatomical pathology is dead? Long live anatomical pathology.

    PubMed

    Nicholls, John M; Francis, Glenn D

    2011-10-01

    The standard diagnostic instrument used for over 150 years by anatomical pathologists has been the optical microscope and glass slide. The advent of immunohistochemistry in the routine laboratory in the 1980s, followed by in situ hybridisation in the 1990s, has increased the armamentaria available to the diagnostic pathologist, and this technology has led to changed patient management in a limited number of neoplastic diseases. The first decade of the 21 century has seen an increasing number of publications using proteomic technologies that promise to change disease diagnosis and management, the traditional role of an anatomical pathologist. Despite the plethora of publications on proteomics and pathology, to date there are actually limited data where proteomic technologies do appear to be of greater diagnostic value than the standard histological slide. Though proteomic techniques will become more prevalent in the future, it will need the expertise of an anatomical pathologist to dissect out and validate this added information. PMID:21876472

  17. [Pathological-anatomical aspects of vagabondage (author's transl)].

    PubMed

    Veith, G; Schwindt, W

    1976-01-01

    Autopsies of 65 agabonds including 2 females are evaluated. Dwarfism, kyphoskoliosis and other skeletal deformities, malformations, disfigurations of the face and tatoo-marks are frequent exteriors. Compared with autopsies in other grous of population there are also numerical differences in internal diseases: In equivalent age groups ulcers of the stomach, duodenum or gastric resection respectively are found in 35,4% of our colective, in 8, % of clinical autopsies and in 4,8% of epileptic patients. Furthermore hypertension, myocardial infarction, chronic emphysema of the lungs and active tuberculosis of the lung are more frequent than in control groups... PMID:1044291

  18. Technical and anatomical aspects of novalis stereotactic radiosurgery sphenopalatine ganglionectomy

    SciTech Connect

    De Salles, Antonio A.F. . E-mail: adesalles@mednet.ucla.edu; Gorgulho, Alessandra; Golish, S. Raymond Ph.D.; Medin, Paul M.; Malkasian, Dennis; Solberg, Timothy D.; Selch, Michael T.

    2006-11-15

    Background: Several techniques have been applied for destruction of the sphenopalatine ganglion to control cluster headache and ocular pain with sympathetic component. Cluster headache has responded to radiofrequency ablation or phenol destruction. Radiosurgery of the sphenopalatine ganglion is promising due to the excellent visualization of the target on magnetic resonance imaging (MRI), computed tomography (CT), and skull X-rays. Material and Methods: Six patients and one cadaver head were analyzed in this study. The cadaver-head dissection confirmed the location of the sphenopalatine ganglion on X-rays and CT imaging. One patient undergoing radiofrequency sphenopalatine ablation participated for confirmation of the location of the ganglion on plain X-rays. Five patients received radiosurgery of the sphenopalatine ganglion. One patient had classic unilateral cluster headache. Two patients had neuropathic pain and 1 had bilateral migrainous neuralgia. The fifth patient had bilateral atypical facial pain. All received a single maximal dose of 90 Gy with a 5- or 7.5-mm circular collimator. MRI, CT, and skull X-rays identified and confirmed the target. Results: The sphenopalatine fossa is seen in the skull X-ray as an inverse tear drop just caudal to the sphenoid sinus. This location is readily correlated to the CT target by the stereotactic coordinates and confirmed with the presence of the ganglion visualized in the MRI scan. Only the patient with cluster headache experienced lasting pain relief. Conclusion: Multiple imaging modalities confirmed the location of the sphenopalatine ganglion for radiosurgery. The procedure was performed safely with CT and MRI fusion. Radiosurgery was significantly beneficial only on classic cluster headache.

  19. Orthodontic extrusion of horizontally impacted mandibular molars

    PubMed Central

    Ma, Zhigui; Yang, Chi; Zhang, Shanyong; Xie, Qianyang; Shen, Yuqing; Shen, Pei

    2014-01-01

    Objective: To introduce and evaluate a novel approach in treating horizontally impacted mandibular second and third molars. Materials and methods: An orthodontic technique was applied for treatment of horizontally impacted mandibular second and third molars, which included a push-type spring for rotation first, and then a cantilever for extrusion. There were 8 mandibular third molars (M3s) and 2 second molars (M2s) in this study. Tooth mobility, extraction time, the inclination and parallelism of the impacted tooth, alveolar bone height of the adjacent tooth, and the relationship of impacted M3 and the inferior alveolar nerve (IAN) were evaluated. Results: Two horizontally impacted M2s could be upright in the arch and good occlusal relationships were obtained after treatment. All impacted M3s were successfully separated from the IAN, without any neurologic consequences. The average extraction time was 5 minutes. There was a significant change in the inclination and parallelism of the impacted tooth after treatment. A new bone apposition with the average height of 3.2 mm was noted distal to the adjacent tooth. Conclusions: This two-step orthodontic technique as presented here may be a safe and feasible alternative in management of severely horizontally impacted mandibular molars, which achieves a successful separation of M3s from the IAN and an excellent position for M2s. PMID:25419364

  20. Oxygen from Hydrogen Peroxide. A Safe Molar Volume-Molar Mass Experiment.

    ERIC Educational Resources Information Center

    Bedenbaugh, John H.; And Others

    1988-01-01

    Describes a molar volume-molar mass experiment for use in general chemistry laboratories. Gives background technical information, procedures for the titration of aqueous hydrogen peroxide with standard potassium permanganate and catalytic decomposition of hydrogen peroxide to produce oxygen, and a discussion of the results obtained in three…

  1. Delayed removal of a maxillary third molar from the infratemporal fossa.

    PubMed

    Gómez-Oliveira, Guillermo; Arribas-García, Ignacio; Alvarez-Flores, Modesto; Gregoire-Ferriol, Johanna; Martínez-Gimeno, Carlos

    2010-05-01

    Removal of an impacted superior third molar is usually a simple and uncomplicated procedure for an Oral and Maxillofacial Surgeon. Nevertheless, complications are possible and include infection, facial swallowing, trismus, wound dehiscence, root fracture or even orosinusal fistula. Iatrogenic displacement into the infratemporal fossa is frequently mentioned but rarely reported. This anatomical fossa includes several important structures such as the internal maxillary artery, the venous pterygoid plexus, the sphenopalatine nerve, the coronoid process of the mandible and the pterygoid muscles. Recommended treatment includes immediate surgical removal if possible or initial observation and secondary removal, as necessary, because of infection, limited mandibular movement, inability to extract the tooth, or the patient's psychological unease. Sometimes, the displaced tooth may spontaneously migrate inferiorly and becomes accessible intraorally. This report describes the location and secondary surgical removal of a left maxillary third molar displaced into the infratemporal fossa, two weeks after first attempt at extraction. PMID:20038889

  2. Lower third molar eruption following orthodontic treatment.

    PubMed

    Salehi, P; Danaie, S Momene

    2008-01-01

    This study assessed the effect of extraction and preservation of the 1st premolar on lower 3rd molar eruption. Orthodontic clinic records from 1993 to 1995 were evaluated before and after treatment and 8-9 years after treatment for 3 groups of patients: 32 with extraction of 1st premolars in both jaws, 32 with no extraction but orthodontic treatment and 48 controls with no extraction but orthodontic treatment in the upper jaws only. Successful eruption of 3rd molars was evaluated. There was a significant difference in the rates of successful eruptions in the extraction (42%), non-extraction (12%) and control (20%) groups. The findings indicate that 1st premolar extraction may increase the chance of 3rd molar eruption, leading to a lower incidence of health and economic complications. PMID:19161121

  3. Molar and molecular views of choice.

    PubMed

    Baum, William M

    2004-06-30

    The molar and molecular views of behavior are not different theories or levels of analysis; they are different paradigms. The molecular paradigm views behavior as composed of discrete units (responses) occurring at moments in time and strung together in chains to make up complex performances. The discrete pieces are held together as a result of association by contiguity. The molecular view has a long history both in early thought about reflexes and in associationism, and, although it was helpful to getting a science of behavior started, it has outlived its usefulness. The molar view stems from a conviction that behavior is continuous, as argued by John Dewey, Gestalt psychologists, Karl Lashley, and others. The molar paradigm views behavior as inherently extended in time and composed of activities that have integrated parts. In the molar paradigm, activities vary in their scale of organization--i.e., as to whether they are local or extended--and behavior may be controlled sometimes by short-term relations and sometimes by long-term relations. Applied to choice, the molar paradigm rests on two simple principles: (a) all behavior constitutes choice; and (b) all activities take time. Equivalence between choice and behavior occurs because every situation contains more than one alternative activity. The principle that behavior takes time refers not simply to any notion of response duration, but to the necessity that identifying one action or another requires a sample extended in time. The molecular paradigm's momentary responses are inferred from extended samples in retrospect. In this sense, momentary responses constitute abstractions, whereas extended activities constitute concrete particulars. Explanations conceived within the molecular paradigm invariably involve hypothetical constructs, because they require causes to be contiguous with responses. Explanations conceived within the molar paradigm retain direct contact with observable variables. PMID:15157981

  4. [Pulmonary Echinococcosis: Surgical Aspects].

    PubMed

    Eichhorn, M E; Hoffmann, H; Dienemann, H

    2015-10-01

    Pulmonary cystic echinococcosis is a very rare disease in Germany. It is caused by the larvae of the dog tapeworm (echinococcus granulosus). The liver is the most affected organ, followed by the lungs. Surgery remains the main therapeutic approach for pulmonary CE. Whenever possible, parenchyma-preserving lung surgery should be preferred over anatomic lung resections. To ensure best therapeutic results, surgery needs to be performed under precise consideration of important infectiological aspects and patients should be treated in specialised centres based on interdisciplinary consensus. In addition to surgical aspects, this review summarises special infectiological features of this disease, which are crucial to the surgical approach. PMID:26351761

  5. Anatomically accurate individual face modeling.

    PubMed

    Zhang, Yu; Prakash, Edmond C; Sung, Eric

    2003-01-01

    This paper presents a new 3D face model of a specific person constructed from the anatomical perspective. By exploiting the laser range data, a 3D facial mesh precisely representing the skin geometry is reconstructed. Based on the geometric facial mesh, we develop a deformable multi-layer skin model. It takes into account the nonlinear stress-strain relationship and dynamically simulates the non-homogenous behavior of the real skin. The face model also incorporates a set of anatomically-motivated facial muscle actuators and underlying skull structure. Lagrangian mechanics governs the facial motion dynamics, dictating the dynamic deformation of facial skin in response to the muscle contraction. PMID:15455936

  6. 40 CFR Table 1 to Subpart Ja of... - Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Molar Exhaust Volumes and Molar Heat... Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents Constituent MEVa dscf/mol MHCb Btu/mol... Inerts 0.85 0 a MEV = molar exhaust volume, dry standard cubic feet per gram-mole (dscf/g-mol)...

  7. 40 CFR Table 1 to Subpart Ja of... - Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Molar Exhaust Volumes and Molar Heat... Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents Constituent MEVa dscf/mol MHCb Btu/mol... Inerts 0.85 0 a MEV = molar exhaust volume, dry standard cubic feet per gram-mole (dscf/g-mol)...

  8. Ectopic molar pregnancy: a case report

    PubMed Central

    Bousfiha, Najoua; Erarhay, Sanaa; Louba, Adnane; Saadi, Hanan; Bouchikhi, Chahrazad; Banani, Abdelaziz; Fatemi, Hind El; Sekkal, Med; Laamarti, Afaf

    2012-01-01

    The incidence of hydatidiform moles is 1 per 1,000 pregnancies. Ectopic pregnancy occurs in 20 per 1,000 pregnancies. Thus, the incidence of the ectopic molar gestation is very rare. We report a case of tubal molar pregnancy diagnosed at the systematic histology exam of an ectopic pregnancy. We report the case of 32 years old nulliparus women who presented a vaginal bleeding, lower abdominal pain and 6 weeks amenorrhea corresponding to the last menstrual period. At the clinical examination, the arterial pressure was 100/60 mmHG. The gynecological examination was difficult because of lower abdominal pain. Serum gonadotropin activity was 3454 ui/l. Pelvic ultrasound revealed an irregular echogenic mass in the left adnexa. Diagnostic laparoscopy revealed a left-sided unruptured ampullary ectopic pregnancy. A left laparoscopic salpingectomy was performed. The systematic histologic test identified an ectopic partial molar pregnancy, which was confirmed by DNA ploidy image analysis. The patient was followed with weekly quantitative B-hCG titers until three successive B-hCG levels were negative. It is pertinent that clinicians take routine histological examination of tubal specimens in ectopic pregnancy very seriously in order to diagnose cases of ectopic molar gestations early and mount appropriate post treatment surveillance. PMID:22655097

  9. Ectopic molar pregnancy: a case report.

    PubMed

    Bousfiha, Najoua; Erarhay, Sanaa; Louba, Adnane; Saadi, Hanan; Bouchikhi, Chahrazad; Banani, Abdelaziz; El Fatemi, Hind; Sekkal, Med; Laamarti, Afaf

    2012-01-01

    The incidence of hydatidiform moles is 1 per 1,000 pregnancies. Ectopic pregnancy occurs in 20 per 1,000 pregnancies. Thus, the incidence of the ectopic molar gestation is very rare. We report a case of tubal molar pregnancy diagnosed at the systematic histology exam of an ectopic pregnancy. We report the case of 32 years old nulliparus women who presented a vaginal bleeding, lower abdominal pain and 6 weeks amenorrhea corresponding to the last menstrual period. At the clinical examination, the arterial pressure was 100/60 mmHG. The gynecological examination was difficult because of lower abdominal pain. Serum gonadotropin activity was 3454 ui/l. Pelvic ultrasound revealed an irregular echogenic mass in the left adnexa. Diagnostic laparoscopy revealed a left-sided unruptured ampullary ectopic pregnancy. A left laparoscopic salpingectomy was performed. The systematic histologic test identified an ectopic partial molar pregnancy, which was confirmed by DNA ploidy image analysis. The patient was followed with weekly quantitative B-hCG titers until three successive B-hCG levels were negative. It is pertinent that clinicians take routine histological examination of tubal specimens in ectopic pregnancy very seriously in order to diagnose cases of ectopic molar gestations early and mount appropriate post treatment surveillance. PMID:22655097

  10. Mass versus molar doses, similarities and differences.

    PubMed

    Chmielewska, A; Lamparczyk, H

    2008-11-01

    Generally, they are two systems expressing the amounts of active substance in a given drug product, i.e. mass and molar dose. Currently, the dose system based on the mass is widely used in which doses are expressed in grams or milligrams. On the other hand, the molar dose system is in direct relation to the number of molecules. Hence, the objective of this work was to compare both systems in order to find their advantages and disadvantages. Active substances belonging to the groups of antibiotics, nootropic agents, beta-blockers, vitamins, GABA-analog, COX-2 inhibitors, calcium channel antagonists, benzodiazepine receptor agonists, lipid-modifying agents (fibrates), non-steroidal anti-inflammatory drugs (profens), estrogens, neuroleptics, analgesics and benzodiazepines were considered. Moreover, products containing two active substances were also taken into account. These are mixtures of hydrochlorothiazide with active substances influencing the renin-angiotensin system and combined oral contraceptives. For each active substance, belonging to the groups mentioned above molar doses were calculated from mass doses and molar mass. Hence, groups of drugs with a single active substance, drugs with similar pharmacological activities, pharmaceutical alternatives, and drugs with a single active ingredient manufactured in different doses were compared in order to find which dose system describes more adequately differences between and within the groups mentioned above. Comparisons were supported by a number of equations, which theoretically justify the data, and relationships derived from calculations. PMID:19069248

  11. Selective alveolar corticotomy to intrude overerupted molars.

    PubMed

    Oliveira, Dauro Douglas; de Oliveira, Bruno Franco; de Araújo Brito, Helio Henrique; de Souza, Margareth Maria Gomes; Medeiros, Paulo José

    2008-06-01

    Orthodontic intrusion of overerupted molars in adults is challenging for most clinicians. Efficient intrusion can be achieved by combining selective alveolar corticotomies with a modified full-coverage maxillary splint to reduce surgical risks, treatment time, and costs for both orthodontists and patients. PMID:18538256

  12. Till Surgery do us Part: Unexpected Bilateral Kissing Molars

    PubMed Central

    Anish, Narayanankutty; Vivek, Velayudhannair; Thomas, Sunila; Daniel, Vineet Alex; Thomas, Jincy; Ranimol, Prasanna

    2015-01-01

    The occurrence impacted teeth, single or multiple is very common. But, phenomenon of kissing molars is an extremely rare phenomenon. Mandibular third molars are the most common impacted teeth. Mandibular first or second molars does not share the same frequency of occurrence. But, there are rare cases in which the occlusal surfaces of impacted molars are united by the same follicular space and the roots point in the opposite direction, and are termed as kissing molars. Sometimes, these teeth will be associated with pathologies. This article reports a rare case of mandibular bilateral kissing molars. PMID:25918627

  13. Treatment of 3rd molar-induced periodontal defects with guided tissue regeneration.

    PubMed

    Oxford, G E; Quintero, G; Stuller, C B; Gher, M E

    1997-07-01

    Recent reports provide evidence of increased attachment levels when using guided tissue regeneration (GTR) techniques for the treatment of periodontal defects. Periodontal defects frequently occur at the distal aspect of mandibular 2nd molars which are next to mesioangular impacted 3rd molars that have oral communication. The purpose of this study was to determine whether the use of GTR can enhance probing attachment levels (PALs) following extraction of mesioangular impacted third molars. 12 patients with bilateral soft tissue impacted mandibular 3rd molars entered this split mouth study. After extractions, the previously exposed distal root surface of the 2nd molars were debrided. The defects on the randomly selected experimental sites were covered with expanded polytetraflouro-ethylene (e-PTFE) membrane and the tissue was replaced to cover the membrane. Membranes were removed after 6 weeks. Control sites were treated identically except no membrane was placed. GI, P1I, PD, PAL and BOP records were obtained at 0, 3 and 6 months. The use of barrier material did not provide statistically-significant differences in PAL when comparing experimental versus control sites. Nevertheless, PAL gain was consistently greater at 3 and 6 months when GTR techniques were used in sites with deep impactions. PMID:9226386

  14. [International anatomical terminology: controversial issues].

    PubMed

    Bolgov, Yu A

    2012-01-01

    The article contains an analysis of problems related to the content of the International anatomical terminology (IAT): the relationship and differences between the terms and concepts as the elements of the professional language of morphologists; forms in which concepts are reflected in IAT; classification of the IAT terms according to the principle of their relationship to the categories of concrete and abstract concepts. PMID:23659048

  15. The anatomical basis of prosopagnosia

    PubMed Central

    Meadows, J. C.

    1974-01-01

    Evidence is presented that patients with prosopagnosia have right anterior inferior occipital lesions in the region of the occipital temporal junction. Many if not all cases have an additional lesion in the left hemisphere; this is often but apparently not always symmetrical with the right hemisphere lesion. This evidence is discussed in relation to the anatomical connections of these regions and the results of experiments in animals. Images PMID:4209556

  16. Anatomical challenges for transcatheter mitral valve intervention.

    PubMed

    DE Backer, Ole; Luk, Ngai H; Søndergaard, Lars

    2016-06-01

    Following the success of transcatheter aortic and pulmonary valve implantation, there is a large interest in transcatheter mitral valve interventions to treat severe mitral regurgitation (MR). With the exception for the MitraClipTM (Abbott, Abbott Park, IL, USA) edge-to-edge leaflet plication system, most of these transcatheter mitral valve interventions are still in their early clinical or preclinical development phase. Challenges arising from the complex anatomy of the mitral valve and the interplay of the mitral apparatus with the left ventricle (LV) have contributed to a more difficult development process and mixed clinical results with these novel technologies. This review aims to discuss the several anatomical aspects and challenges related to transcatheter mitral valve intervention - the relevant anatomy will be reviewed in relation to specific requirements for device design and procedural aspects of transcatheter mitral valve interventions. To date, experience with these novel therapeutic modalities are still limited and resolution of many challenges are pending. Future studies have to evaluate for whom the transcatheter approach is a feasible and preferred treatment and which patients will benefit from either transcatheter mitral valve repair or replacement. Nevertheless, technological developments are anticipated to drive the transcatheter approach forward into a clinically feasible alternative to surgery for selected patients with severe MR. PMID:27028333

  17. Removal of Deeply Impacted Mandibular Molars by Sagittal Split Osteotomy

    PubMed Central

    Isler, Sabri Cemil

    2016-01-01

    Mandibular third molars are the most common impacted teeth. Mandibular first and second molars do not share the same frequency of occurrence. In rare cases the occlusal surfaces of impacted molars are united by the same follicular space and the roots pointing in opposite direction; these are called kissing molars. In some cases, a supernumerary fourth molar can be seen as unerupted and, in this case, such a supernumerary, deeply impacted fourth molar is seen neighboring kissing molars. The extraction of deeply impacted wisdom molars from the mandible may necessitate excessive bone removal and it causes complications such as damage to the inferior alveolar nerve and iatrogenic fractures of the mandible. This case report describes the use of the sagittal split osteotomy technique to avoid extensive bone removal and protect the inferior alveolar nerve during surgical extruction of multiple impacted teeth. PMID:27429810

  18. Enzyme Molar Fractions: A Powerful Tool for Understanding Enzyme Kinetics.

    ERIC Educational Resources Information Center

    Serra, Juan L.; And Others

    1986-01-01

    Deduces the relationship between reduced velocity and molar fractions for productive enzyme complexes; obtains the mathematical expression of molar fractions for an enzyme with two specific binding sites per molecule; and proposes a useful plot to follow the dependence of enzyme molar fractions with the concentration of one of its ligands. (JN)

  19. Molar tubal ectopic pregnancy: Report of two cases.

    PubMed

    Mbarki, Chaouki; Jerbi, Emna; Hsayaoui, Najeh; Zouari, Fatma; Ben Brahim, Ehsen; Oueslati, Hedhili

    2015-06-01

    Ectopic molar pregnancy is a rare occurrence and consequently not often considered as a diagnostic possibility. We report two cases of molar hydatidiform tubal pregnancy. Diagnosis of ectopic pregnancy was confirmed on clinical biological and sonographic investigations. Diagnosis of molar pregnancy was done on histopathology. The clinical course was favorable for both patients. Although rare, molar changes can occur at any site of an ectopic pregnancy. Clinical diagnosis of a molar pregnancy is difficult but histopathology is the gold standard for diagnosis. PMID:25510265

  20. Periodontal changes following molar intrusion with miniscrews

    PubMed Central

    Bayani, Shahin; Heravi, Farzin; Radvar, Mehrdad; Anbiaee, Najmeh; Madani, Azam Sadat

    2015-01-01

    Background: With the introduction of skeletal anchorage system, recently it is possible to successfully intrude molar teeth. On the other hand, there have been concerns about periodontal changes associated with intrusion and there are few studies on this topic, especially for posterior teeth. Materials and Methods: Ten female patients were enrolled in this study. Maxillary molar intrusion was achieved by inserting two miniscrews and a 17 × 25 titanium molybdenum alloy spring. Crestal height changes were evaluated at three intervals including: Baseline (T0), end of active treatment (T1) and 6 months after retention (T2). Other variables including probing depth, gingival recession, attachment level and bleeding on probing were evaluated by clinical measurements in the three above mentioned intervals. One-sample Kolmogrov-Smirnov test ascertained the normality of the data. For all patients, the changes in tooth position and crestal height were evaluated using one-sample t-test. (P < 0.05) Results: Supra-erupted molars were successfully intruded a mean of 2.1 ± 0.9 mm during active treatment (T0-T1). A mean bone resorption of 0.9 ± 0.9 mm in mesial crest and 1 ± 0.8 mm in distal crest had occurred in total treatment (T0-T2). A mean of 0.6 ± 1.4 mm bone was deposited on mesial crest during the retention period (T1-T2) following tooth relapse. On average, 0.8 ± 0.4 mm attachment gain was obtained. Gingival margin coronalized a mean of 0.8 ± 0.6 mm throughout the entire treatment. Probing depth showed no significant change during treatment. Conclusion: Within the limitations of this study, these results suggest that not only periodontal status was not negatively affected by intrusion, but also there were signs of periodontal improvement including attachment gain and shortening of clinical crown height. PMID:26288629

  1. Angle Class II, subdivision, with agenesis of mandibular second molars and extrusion of maxillary second molars *

    PubMed Central

    Tavares, Rubens Rodrigues

    2015-01-01

    This clinical case reports the treatment of an Angle Class II malocclusion in a young woman with a balanced face affected by agenesis of second and third mandibular molars and subsequent extrusion of second maxillary molars. The atypical and peculiar occlusal anomaly led to individualized treatment proposed in order to normalize dental malpositions, with subsequent rehabilitation of edentulous areas by means of a multidisciplinary approach. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) in partial fulfillment of the requirements for obtaining the title of certified by the BBO. PMID:25992995

  2. Brain anatomical network and intelligence.

    PubMed

    Li, Yonghui; Liu, Yong; Li, Jun; Qin, Wen; Li, Kuncheng; Yu, Chunshui; Jiang, Tianzi

    2009-05-01

    Intuitively, higher intelligence might be assumed to correspond to more efficient information transfer in the brain, but no direct evidence has been reported from the perspective of brain networks. In this study, we performed extensive analyses to test the hypothesis that individual differences in intelligence are associated with brain structural organization, and in particular that higher scores on intelligence tests are related to greater global efficiency of the brain anatomical network. We constructed binary and weighted brain anatomical networks in each of 79 healthy young adults utilizing diffusion tensor tractography and calculated topological properties of the networks using a graph theoretical method. Based on their IQ test scores, all subjects were divided into general and high intelligence groups and significantly higher global efficiencies were found in the networks of the latter group. Moreover, we showed significant correlations between IQ scores and network properties across all subjects while controlling for age and gender. Specifically, higher intelligence scores corresponded to a shorter characteristic path length and a higher global efficiency of the networks, indicating a more efficient parallel information transfer in the brain. The results were consistently observed not only in the binary but also in the weighted networks, which together provide convergent evidence for our hypothesis. Our findings suggest that the efficiency of brain structural organization may be an important biological basis for intelligence. PMID:19492086

  3. Brain Anatomical Network and Intelligence

    PubMed Central

    Li, Jun; Qin, Wen; Li, Kuncheng; Yu, Chunshui; Jiang, Tianzi

    2009-01-01

    Intuitively, higher intelligence might be assumed to correspond to more efficient information transfer in the brain, but no direct evidence has been reported from the perspective of brain networks. In this study, we performed extensive analyses to test the hypothesis that individual differences in intelligence are associated with brain structural organization, and in particular that higher scores on intelligence tests are related to greater global efficiency of the brain anatomical network. We constructed binary and weighted brain anatomical networks in each of 79 healthy young adults utilizing diffusion tensor tractography and calculated topological properties of the networks using a graph theoretical method. Based on their IQ test scores, all subjects were divided into general and high intelligence groups and significantly higher global efficiencies were found in the networks of the latter group. Moreover, we showed significant correlations between IQ scores and network properties across all subjects while controlling for age and gender. Specifically, higher intelligence scores corresponded to a shorter characteristic path length and a higher global efficiency of the networks, indicating a more efficient parallel information transfer in the brain. The results were consistently observed not only in the binary but also in the weighted networks, which together provide convergent evidence for our hypothesis. Our findings suggest that the efficiency of brain structural organization may be an important biological basis for intelligence. PMID:19492086

  4. Digital imaging in anatomic pathology.

    PubMed

    O'Brien, M J; Sotnikov, A V

    1996-10-01

    Advances in computer technology continue to bring new innovations to departments of anatomic pathology. This article briefly reviews the present status of digital optical imaging, and explores the directions that this technology may lead over the next several years. Technical requirements for digital microscopic and gross imaging, and the available options for image archival and retrieval are summarized. The advantages of digital images over conventional photography in the conference room, and the usefulness of digital imaging in the frozen section suite and gross room, as an adjunct to surgical signout and as a resource for training and education, are discussed. An approach to the future construction of digital histologic sections and the computer as microscope is described. The digital technologic applications that are now available as components of the surgical pathologist's workstation are enumerated. These include laboratory information systems, computerized voice recognition, and on-line or CD-based literature searching, texts and atlases and, in some departments, on-line image databases. The authors suggest that, in addition to these resources that are already available, tomorrow's surgical pathology workstation will include network-linked digital histologic databases, on-line software for image analysis and 3-D image enhancement, expert systems, and ultimately, advanced pattern recognition capabilities. In conclusion, the authors submit that digital optical imaging is likely to have a significant and positive impact on the future development of anatomic pathology. PMID:8853053

  5. Anatomical heterogeneity of Alzheimer disease

    PubMed Central

    Noh, Young; Jeon, Seun; Seo, Sang Won; Kim, Geon Ha; Cho, Hanna; Ye, Byoung Seok; Yoon, Cindy W.; Kim, Hee Jin; Chin, Juhee; Park, Kee Hyung; Heilman, Kenneth M.

    2014-01-01

    Objective: Because the signs associated with dementia due to Alzheimer disease (AD) can be heterogeneous, the goal of this study was to use 3-dimensional MRI to examine the various patterns of cortical atrophy that can be associated with dementia of AD type, and to investigate whether AD dementia can be categorized into anatomical subtypes. Methods: High-resolution T1-weighted volumetric MRIs were taken of 152 patients in their earlier stages of AD dementia. The images were processed to measure cortical thickness, and hierarchical agglomerative cluster analysis was performed using Ward's clustering linkage. The identified clusters of patients were compared with an age- and sex-matched control group using a general linear model. Results: There were several distinct patterns of cortical atrophy and the number of patterns varied according to the level of cluster analyses. At the 3-cluster level, patients were divided into (1) bilateral medial temporal–dominant atrophy subtype (n = 52, ∼34.2%), (2) parietal-dominant subtype (n = 28, ∼18.4%) in which the bilateral parietal lobes, the precuneus, along with bilateral dorsolateral frontal lobes, were atrophic, and (3) diffuse atrophy subtype (n = 72, ∼47.4%) in which nearly all association cortices revealed atrophy. These 3 subtypes also differed in their demographic and clinical features. Conclusions: This cluster analysis of cortical thickness of the entire brain showed that AD dementia in the earlier stages can be categorized into various anatomical subtypes, with distinct clinical features. PMID:25344382

  6. Mechanics analysis of molar tooth splitting.

    PubMed

    Barani, Amir; Chai, Herzl; Lawn, Brian R; Bush, Mark B

    2015-03-01

    A model for the splitting of teeth from wedge loading of molar cusps from a round indenting object is presented. The model is developed in two parts: first, a simple 2D fracture mechanics configuration with the wedged tooth simulated by a compact tension specimen; second, a full 3D numerical analysis using extended finite element modeling (XFEM) with an embedded crack. The result is an explicit equation for splitting load in terms of indenter radius and key tooth dimensions. Fracture experiments on extracted human molars loaded axially with metal spheres are used to quantify the splitting forces and thence to validate the model. The XFEM calculations enable the complex crack propagation, initially in the enamel coat and subsequently in the interior dentin, to be followed incrementally with increasing load. The fracture evolution is shown to be stable prior to failure, so that dentin toughness, not strength, is the controlling material parameter. Critical conditions under which tooth splitting in biological and dental settings are likely to be met, however rare, are considered. PMID:25584989

  7. Positional changes of the third molar in orthodontically treated patients

    PubMed Central

    Mihai, AM; Lulache, IR; Grigore, R; Sanabil, AS; Boiangiu, S; Ionescu, E

    2013-01-01

    Objective and Rationale. Over the years, the effects of the third molars eruption on the dental arches have been studied extensively. Still, literature provides less data regarding the effects of the orthodontic treatment on the third molars position. The aim of our study was to assess the positional changes of the third molars relative to the occlusal plane and to the second molar long axis, changes occurred during orthodontic treatment performed with or without premolar extractions. Method. This study included 20 orthodontic treated patients: 10 of them with premolar extractions and 10 without premolar extractions. The pretreatment and post treatment panoramic radiographs were analyzed, and the angles between the third molar long axis and the occlusal plane and between the long axis of the third molar and the long axis of the second molar were measured. Results. Changes in third molar position, from pretreatment to post treatment, for the two groups of patients were evaluated by using the Student’s t-test. The results of the statistical analysis revealed an improvement in third molars position, the best results were seen in the lower third molars, in the group of patients treated with premolar extractions. PMID:23904878

  8. Anatomic consideration for preventive implantation.

    PubMed

    Denissen, H W; Kalk, W; Veldhuis, H A; van Waas, M A

    1993-01-01

    The aim of preventive implant therapy is to prevent or delay loss of alveolar ridge bone mass. For use in an anatomic study of 60 mandibles, resorption of the alveolar ridge was classified into four preventive stages: (1) after extraction of teeth; (2) after initial resorption; (3) when the ridge has atrophied to a knife-edge shape; and (4) when only basal bone remains. Implantation in stage 3 necessitates removal of the knife-edge ridge to create space for cylindrical implants. Therefore, implantation in stage 2 is advocated to prevent the development of stage 3. The aim of implantation in stage 4 is to prevent total loss of function of the atrophic mandible. PMID:8359876

  9. Digital photography in anatomical pathology.

    PubMed

    Leong, F J; Leong, A S

    2004-01-01

    Digital imaging has made major inroads into the routine practice of anatomical pathology and replaces photographic prints and Kodachromes for reporting and conference purposes. More advanced systems coupled to computers allow greater versatility and speed of turnaround as well as lower costs of incorporating macroscopic and microscopic pictures into pathology reports and publications. Digital images allow transmission to remote sites via the Internet for consultation, quality assurance and educational purposes, and can be stored on and disseminated by CD-ROM. Total slide digitisation is now a reality and will replace glass slides to a large extent. Three-dimensional images of gross specimens can be assembled and posted on websites for interactive educational programmes. There are also applications in research, allowing more objective and automated quantitation of a variety of morphological and immunohistological parameters. Early reports indicate that medical vision systems are a reality and can provide for automated computer-generated histopathological diagnosis and quality assurance. PMID:15048004

  10. Endodontic treatment of the mandibular first molar with six roots canals - two case reports and literature review.

    PubMed

    Martins, Jorge N R; Anderson, Craig

    2015-04-01

    The most common configuration of the mandibular first molar is the presence of two roots and three root canals. The objective of this work is to present two rare anatomic configurations with six root canals on two mandibular left first molars diagnosed during endodontic therapy. Root canal therapy was performed using a dental operating microscope. Ultrasonic troughing in the grooves in between the mesial root canals and in between the distal root canals was able to show the middle root canals. Large samples population characterization researches and systematic reviews were unable to detect a single case of six root canals configuration in a mandibular first molar in their investigations. Although it is a rare configuration, a six root canal configuration is possible to be found in the mandibular first molar. Three different pulp chamber configurations are possible to be found. Two or three roots may be present and the root configuration more common in the mesial root is the Type 8 and Type 12 for the distal root. Some concepts about the required technique to approach these cases are also debated. PMID:26023651

  11. Endodontic Treatment of the Mandibular First Molar with Six Roots Canals – Two Case Reports and Literature Review

    PubMed Central

    Anderson, Craig

    2015-01-01

    The most common configuration of the mandibular first molar is the presence of two roots and three root canals. The objective of this work is to present two rare anatomic configurations with six root canals on two mandibular left first molars diagnosed during endodontic therapy. Root canal therapy was performed using a dental operating microscope. Ultrasonic troughing in the grooves in between the mesial root canals and in between the distal root canals was able to show the middle root canals. Large samples population characterization researches and systematic reviews were unable to detect a single case of six root canals configuration in a mandibular first molar in their investigations. Although it is a rare configuration, a six root canal configuration is possible to be found in the mandibular first molar. Three different pulp chamber configurations are possible to be found. Two or three roots may be present and the root configuration more common in the mesial root is the Type 8 and Type 12 for the distal root. Some concepts about the required technique to approach these cases are also debated. PMID:26023651

  12. Clinical Success Rate of Compomer and Amalgam Class II Restorations in First Primary Molars: A Two-year Study

    PubMed Central

    Ghaderi, Faezeh; Mardani, Ali

    2015-01-01

    Background and aims. The majority of failures in Class II amalgam restorations occur in the first primary molar teeth; in addition, use of compomer instead of amalgam for primary molar teeth restorations is a matter of concern. The aim ofthe present study was to compare the success rate of Class II compomer and amalgam restorations in the first primary molars. Materials and methods. A total of 17 amalgams and 17 compomer restorations were placed in 17 children based on a split-mouth design. Restorations were assessed at 12- and 24-month intervals for marginal integrity, the anatomic form and recurrent caries. Data were analyzed with SPSS 11. Chi-squared test was applied for the analysis. Statistical significance was set at P<0.05. Results. A total 34 restorations of 28 restorations (14 pairs) of the total restorations still survived after 24 months. Compomerrestorations showed significantly better results in marginal integrity. Recurrent caries was significantly lower incompomer restorations compared to amalgam restorations. Cumulative success rate at 24-month interval was significantlyhigher in compomer restorations compared to amalgam restorations. There was no statistically significant difference inanatomic form between the two materials. Conclusion. Compomer appears to be a suitable alternative to amalgam for Class II restorations in the first primary mo-lars. PMID:26236434

  13. Intrusion of overerupted molars by corticotomy and orthodontic skeletal anchorage.

    PubMed

    Moon, Cheol-Hyun; Wee, Jin-Uk; Lee, Hyun-Sun

    2007-11-01

    This article describes the orthodontic treatment of a 26-year-old female patient with overerupted left maxillary molar teeth. Her chief complaint was that the maxillary left first and the second molar intruded into the space required for the mandibular left first and the second molars, preventing prosthodontic treatment. The authors performed a corticotomy and used orthodontic skeletal anchorage with a miniplate and orthodontic miniscrews with a head modified to provide a specially designed hook. With this approach, they were able to achieve a sufficient amount of molar intrusion without discomfort, root resorption, or extrusion of the adjacent teeth. The first molar was intruded 3.0 mm and second molar was intruded 3.5 mm during 2 months of treatment. These results have been maintained for 11 months. PMID:18004918

  14. Molar mass distribution and solubility modeling of asphaltenes

    SciTech Connect

    Yarranton, H.W.; Masliyah, J.H.

    1996-12-01

    Attempts to model asphaltene solubility with Scatchard-Hildebrand theory were hampered by uncertainty in molar volume and solubility parameter distribution within the asphaltenes. By considering asphaltenes as a series of polyaromatic hydrocarbons with randomly distributed associated functional groups, molar volume and solubility parameter distributions are calculated from experimental measurements of molar mass and density. The molar mass distribution of Athabasca asphaltenes is determined from interfacial tension and vapor pressure osmometry measurements together with plasma desorption mass spectrometry determinations from the literature. Asphaltene densities are calculated indirectly from mixtures of known concentration of asphaltene in toluene. Asphaltene density, molar volume, and solubility parameter are correlated with molar mass. Solid-liquid equilibrium calculations based on solubility theory and the asphaltene property correlations successfully predict experimental data for both the precipitation point and the amount of precipitated asphaltenes in toluene-hexane solvent mixtures.

  15. Ab initio molar volumes and Gaussian radii.

    PubMed

    Parsons, Drew F; Ninham, Barry W

    2009-02-12

    Ab initio molar volumes are calculated and used to derive radii for ions and neutral molecules using a spatially diffuse model of the electron distribution with Gaussian spread. The Gaussian radii obtained can be used for computation of nonelectrostatic ion-ion dispersion forces that underlie Hofmeister specific ion effects. Equivalent hard-sphere radii are also derived, and these are in reasonable agreement with crystalline ionic radii. The Born electrostatic self-energy is derived for a Gaussian model of the electronic charge distribution. It is shown that the ionic volumes used in electrostatic calculations of strongly hydrated cosmotropic ions ought best to include the first hydration shell. Ionic volumes for weakly hydrated chaotropic metal cations should exclude electron overlap (in electrostatic calculations). Spherical radii are calculated as well as nonisotropic ellipsoidal radii for nonspherical ions, via their nonisotropic static polarizability tensors. PMID:19140766

  16. Molar extinction coefficients of some fatty acids

    NASA Astrophysics Data System (ADS)

    Sandhu, G. K.; Singh, Kulwant; Lark, B. S.; Gerward, L.

    2002-10-01

    The attenuation of gamma rays in some fatty acids, viz. formic acid (CH 2O 2), acetic acid (C 2H 4O 2), propionic acid (C 3H 6O 2), butyric acid (C 4H 8O 2), n-hexanoic acid (C 6H 12O 2), n-caprylic acid (C 8H 16O 2), lauric acid (C 12H 24O 2), myristic acid (C 14H 28O 2), palmitic acid (C 16H 32O 2), oleic acid (C 18H 34O 2) and stearic acid (C 18H 36O 2), has been measured at the photon energies 81, 356, 511, 662, 1173 and 1332 keV. Experimental values for the molar extinction coefficient, the effective atomic number and the electron density have been derived and compared with theoretical calculations. There is good agreement between experiment and theory.

  17. Cone beam computed tomography evaluation and endodontic management of permanent mandibular second molar with four roots: A rare case report and literature review

    PubMed Central

    Rajasekhara, Subhashini; Sharath Chandra, SM; Parthasarathy, Late Bharath

    2014-01-01

    The morphological variation in the number of roots and root canals, especially in multi-rooted teeth is a constant challenge for diagnosis and successful endodontic therapy. Knowledge of the most common anatomic characteristics and their possible variations is fundamental. Although, endodontic management of four-rooted mandibular first molars have been observed on a few occasions in the literature, to the best of our knowledge four-rooted mandibular second molars having two mesial and two distal roots have not been reported. This paper highlights endodontic management of mandibular second molar with four roots (two mesial and two distal) with one canal in each root and its cone beam computed tomography (CBCT) evaluation which was primarily done for post treatment assessment for diagnosing post-endodontic complications, at the same time confirmed our radiographic diagnosis of this variation. This also helped us portraying the anatomy of this rare variation. PMID:25125856

  18. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    ERIC Educational Resources Information Center

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  19. Endodontic treatment of a maxillary first molar with seven root canals confirmed with cone beam computer tomography - case report.

    PubMed

    Martins, Jorge N R

    2014-06-01

    The most common configuration of the maxillary first molar is the presence of three roots and four root canals, although the presence of several other configurations have already been reported. The objective of this work is to present a rare anatomic configuration with seven root canals diagnosed during an endodontic therapy. Endodontic treatment was performed using a dental operating microscope. Exploring the grooves surrounding the main canals with ultrasonic troughing was able expose unexpected root canals. Instrumentation with files of smaller sizes and tapers was performed to prevent root physical weakness. The anatomic configuration was confirmed with a Cone Beam Computer Tomography image analysis which was able to clearly show the presence of seven root canals. An electronic database search was conducted to identify all the published similar cases and the best techniques to approach them are discussed. PMID:25121069

  20. Endodontic Treatment of a Maxillary First Molar with Seven Root Canals Confirmed with Cone Beam Computer Tomography – Case Report

    PubMed Central

    2014-01-01

    The most common configuration of the maxillary first molar is the presence of three roots and four root canals, although the presence of several other configurations have already been reported. The objective of this work is to present a rare anatomic configuration with seven root canals diagnosed during an endodontic therapy. Endodontic treatment was performed using a dental operating microscope. Exploring the grooves surrounding the main canals with ultrasonic troughing was able expose unexpected root canals. Instrumentation with files of smaller sizes and tapers was performed to prevent root physical weakness. The anatomic configuration was confirmed with a Cone Beam Computer Tomography image analysis which was able to clearly show the presence of seven root canals. An electronic database search was conducted to identify all the published similar cases and the best techniques to approach them are discussed. PMID:25121069

  1. Endodontic management of permanent mandibular molars with 6 root canals: report of 3 cases.

    PubMed

    Malhotra, Amit; Ahlawat, Jyoti; Bansal, Chirag; Tahiliani, Divya

    2016-01-01

    Aberrations in the internal dental anatomy present challenges for clinicians performing endodontic therapy. These challenges have been partly resolved in recent years by a more comprehensive knowledge of root canal anatomy as well as advancements in the endodontic armamentarium. The aim of this case series is to describe successful root canal treatment, under magnification, in 3 cases of mandibular first molars with 6 root canals. Two of these teeth had 2 roots (mesial and distal) with 3 canals in each root; the third tooth had 3 root canals located mesially and 3 present distally as well as a radix entomolaris. A distal root with 3 canals is rare; however, it is important to look for such anatomical variations to ensure successful endodontic therapy. PMID:27599288

  2. Fusion of a supernumerary tooth to right mandibular second molar: a case report and literature review.

    PubMed

    Zhu, Min; Liu, Chao; Ren, Shuangshuang; Lin, Zintong; Miao, Leiying; Sun, Weibin

    2015-01-01

    Gemination or fusion is a rare occurrence in the mandibular posterior teeth. The aim of this article is to describe the problems encountered and the strategy employed in treating such cases. A 34 years old patient came with the complaint of spontaneous and radiating pain in the right mandibular posterior region. The tooth in concern was an anomalous 'double' second mandibular molar diagnosed as having necrotic pulp with chronic apical abscess of endodontic origin. The present case emphasizes the importance of identifying anatomical anomalies during treatment of fused teeth with supernumerary tooth, and the need for the use of advanced imaging modalities like CBCT which is a critical aid in the diagnosis of such cases. Fused teeth can be managed quite efficiently by an overall combined treatment including both endodontic and periodontal therapy. PMID:26550101

  3. Anatomical reconstruction of the anterior cruciate ligament: a logical approach

    PubMed Central

    Gali, Julio Cesar

    2015-01-01

    We describe the surgical approach that we have used over the last years for anterior cruciate ligament (ACL) reconstruction, highlighting the importance of arthroscopic viewing through the anteromedial portal (AMP) and femoral tunnel drilling through an accessory anteromedial portal (AMP). The AMP allows direct view of the ACL femoral insertion site on the medial aspect of the lateral femoral condyle, does not require guides for anatomic femoral tunnel reaming, prevents an additional lateral incision in the distal third of the thigh (as would be unavoidable when the outside-in technique is used) and also can be used for double-bundle ACL reconstruction. PMID:26417571

  4. Autotransplantation of a Buccally Erupted Matured Mandibular Third Molar to Replace a Grossly Decayed Second Molar

    PubMed Central

    Bodh, Ranjeet; Kaushik, Aishvarya; Talwar, Sangeeta

    2016-01-01

    Autotransplantation can be a treatment option for tooth loss as an alternative to fixed or implant-supported prostheses. It has predictable results comparable to implants, with reported success rates often greater than 90%. In present case, buccally erupted matured third molar was autotransplanted in extraction socket of grossly carious mandibular second molar. The tooth was splinted for 1 week followed by root canal treatment. After 12 months follow up, tooth was in perfect state of function and aesthetic with healthy periapical and periodontal architecture. High success rate was found in immature tooth transplantation in previous case reports. This case report describes that even matured tooth can also be used as donor if atraumatic extraction is possible and endodontic treatment is well performed. PMID:27042593

  5. Autotransplantation of a Buccally Erupted Matured Mandibular Third Molar to Replace a Grossly Decayed Second Molar.

    PubMed

    Yadav, Sukhwant Singh; Bodh, Ranjeet; Kaushik, Aishvarya; Talwar, Sangeeta

    2016-02-01

    Autotransplantation can be a treatment option for tooth loss as an alternative to fixed or implant-supported prostheses. It has predictable results comparable to implants, with reported success rates often greater than 90%. In present case, buccally erupted matured third molar was autotransplanted in extraction socket of grossly carious mandibular second molar. The tooth was splinted for 1 week followed by root canal treatment. After 12 months follow up, tooth was in perfect state of function and aesthetic with healthy periapical and periodontal architecture. High success rate was found in immature tooth transplantation in previous case reports. This case report describes that even matured tooth can also be used as donor if atraumatic extraction is possible and endodontic treatment is well performed. PMID:27042593

  6. Anchorage reinforcement with a fixed functional appliance during protraction of the mandibular second molars into the first molar extraction sites.

    PubMed

    Chhibber, Aditya; Upadhyay, Madhur

    2015-07-01

    Protraction of posterior teeth into edentulous spaces is a challenge. This report describes the treatment of a 19-year-old woman with missing mandibular first molars owing to caries. A fixed functional appliance was used for anchorage reinforcement during mandibular second molar protraction. Eight millimeters of bilateral protraction was done with bodily mesial movement of the molars and no lingual tipping of the incisors. PMID:26124039

  7. Singapore's anatomical future: quo vadis?

    PubMed

    Ang, Eng-Tat; Sugand, Kapil; Hartman, Mikael; Seow, Choon-Sheong; Bay, Boon-Huat; Abrahams, Peter

    2012-01-01

    The disciplines of anatomy and surgery are not dichotomous since one is dependent on the other. Traditionally, surgeons predominantly taught gross and clinical anatomy. In this review, we examine the context of how human anatomy is taught nowadays. In essence, we discovered that there are certain discernable trends consistently observable between the American and British systems. In Singapore, the British Russell Group first influenced its education landscape but now more so by the American Ivy League. Singapore now has three medical schools all offering differing anatomy curricula, which serves as an opportune time for it to consider if there is a best approach given that the practice of surgery is also evolving in parallel. This review discusses the various pedagogies and issues involved, and will serve as a forum and stimulus for discussion. By tweaking the curriculum correctly and the lessons learnt, future doctors and surgeons in training will receive a better anatomical education, not just in Singapore but the world in general. Key recommendations include the use of body painting, clay, plasticine to facilitate the learning of anatomy, and the implementation of a body donation program. Furthermore, strategic mergers with key stakeholders will also ensure the survival of the discipline. PMID:22566391

  8. Detection and analysis of statistical differences in anatomical shape.

    PubMed

    Golland, Polina; Grimson, W Eric L; Shenton, Martha E; Kikinis, Ron

    2005-02-01

    We present a computational framework for image-based analysis and interpretation of statistical differences in anatomical shape between populations. Applications of such analysis include understanding developmental and anatomical aspects of disorders when comparing patients versus normal controls, studying morphological changes caused by aging, or even differences in normal anatomy, for example, differences between genders. Once a quantitative description of organ shape is extracted from input images, the problem of identifying differences between the two groups can be reduced to one of the classical questions in machine learning of constructing a classifier function for assigning new examples to one of the two groups while making as few misclassifications as possible. The resulting classifier must be interpreted in terms of shape differences between the two groups back in the image domain. We demonstrate a novel approach to such interpretation that allows us to argue about the identified shape differences in anatomically meaningful terms of organ deformation. Given a classifier function in the feature space, we derive a deformation that corresponds to the differences between the two classes while ignoring shape variability within each class. Based on this approach, we present a system for statistical shape analysis using distance transforms for shape representation and the support vector machines learning algorithm for the optimal classifier estimation and demonstrate it on artificially generated data sets, as well as real medical studies. PMID:15581813

  9. Tomographic Evaluation of Mandibular Thickness on Premolar and Molar Regions Related to Monocortical Screws.

    PubMed

    Ribeiro, Jonathan; Marin, Charles; Homsi, Nicolas; Rocha Junior, Hernando; Magacho, Luiz; Fidalgo, Guto; Zanela, Manuella

    2016-06-01

    The aim of this study was to measure the thickness of the mandible from the external cortical plate to the teeth roots on premolar and molar regions using CT scan to determine the safety margin for the application of monocortical screws for internal rigid fixation. Thirty-one patients underwent CT-scan imaging for surgical planning. The images were used to measure bilaterally the distance from the external cortex of the mandible to the roots of teeth on premolar and molar region by means of Dental Slice software (Bioparts Prototipagem Biomedica, Brasília, DF, Brazil). Mean, median, standard deviation, one-way ANOVA and post hoc Tukey's test were used for statistical analysis. No statistical differences for thickness were found between right and left side (p = 0.1652). The mean thickness for the left side was 4.17 ± 1.68 mm and for right side 3.93 ± 1.49 mm. Increase in mandibular thickness from anterior to posterior regions in both sides was observed and statistical difference was found among the different groups according to the measured region (p < 0.05). The present results can predict the safety zone for the use of monocortical screws in the mandible, but the use of CT scan is imperative and individual analysis is desired owing to anatomical variations. Further studies with larger samples are necessary to confirm these data and should include other anatomic structures, different regions of mandible/maxilla, as well as other ethnic groups. PMID:27162564

  10. Morphologic analysis of third-molar maturity by digital orthopantomographic assessment.

    PubMed

    Introna, Francesco; Santoro, Valeria; De Donno, Antonio; Belviso, Maura

    2008-03-01

    Accurate timing of the eruption of first and permanent teeth is an important parameter in forensic odontology to establish the age of dead or live individuals. Determination of adulthood may determine, for example, whether an individual convicted of a crime is sentenced as an adult and incarcerated in a state penal institution or as a juvenile and sent to a juvenile camp. At present, there is a large immigrant population in Italy, and young foreign criminals sometimes have false passports bearing a later birth date, with the aim of evading punishment. In such circumstances, age determination is becoming a significant forensic issue.Late in adolescence, after formation of the premolars and canines, only the third molars continue to develop. According to several studies, although the third molars are the most variable teeth in the dentition, they remain the most reliable biologic indicator available for estimation of age during the middle teens and early twenties.In this study, the authors test the possibilities offered by orthopantomography executed by means of digital technology, with the aim of exploiting the advantages of the computerized digital technique compared with the conventional technique, to determine adult age on the basis of root development of the third molar.Digital radiography is simple to use, quick, and effective, allowing superimposition and enlargement; the images can be electronically stored and transported. In comparison with traditional orthopantomography, the digital technique features greater diagnostic accuracy of some anatomic structures: upper and lower front teeth, root apexes, floor of the nasal fossa and maxillary sinus, nasal septum, mandibular condylus. Moreover, digital orthopantomography suffers less from artifacts.The digital orthopantomographies of 83 Caucasian subjects (43 females and 40 males) aged between 16 and 22 years were analyzed in standard conditions, assessing the degree of maturation of the upper and lower third

  11. Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars

    PubMed Central

    Sharma, Pranjal; Swamy, Dinesh Francis; Shashidara, R; Swamy, Elaine Barretto

    2015-01-01

    ABSTRACT Need for the study: The most important procedure for a successful endodontic treatment is the cleaning and shaping of the canal system. Understanding the internal anatomy of teeth provides valuable information to the clinician that would help him achieve higher clinical success during endodontic therapy. Aims: To evaluate by computed tomography—the internal anatomy of mandibular second primary molars with respect to the number of canals, cross-sectional shape of canals, cross-sectional area of canals and the root dentin thickness. Materials and methods: A total of 31 mandibular second primary molars were subjected to computed-tomographic evaluation in the transverse plane, after mounting them in a prefabricated template. The images, thus, obtained were analyzed using De-winter Bio-wizard® software. Results: All the samples demonstrated two canals in the mesial root, while majority of the samples (65.48%) demonstrated two canals in the distal root. The cross-sectional images of the mesial canals demonstrated a round shape, while the distal canals demonstrated an irregular shape. The root dentin thickness was highly reduced on the distal aspect of mesial and mesial aspect of distal canals. Conclusion: The mandibular second primary molars demonstrated wide variation and complexities in their internal anatomy. A thorough understanding of the complexity of the root canal system is essential for understanding the principles and problems of shaping and cleaning, determining the apical limits and dimensions of canal preparations, and for performing successful endodontic procedures. How to cite this article: Kurthukoti AJ, Sharma P, Swamy DF, Shashidara R, Swamy EB. Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars. Int J Clin Pediatr Dent 2015;8(3):202-207. PMID:26628855

  12. The maxillary molar endodontic access opening: A microscope-based approach

    PubMed Central

    Mamoun, John Sami

    2016-01-01

    This article reviews the basic clinical techniques of performing a maxillary molar endodontic access opening, starting from the initial access opening into the pulp chamber, to the point where a size #10 file has been advanced to the apices of all three or four (or more) canals. The article explains how the use of the dental surgical operating microscope or microscope-level loupes magnification of ×6–8 or greater, combined with head-mounted or coaxial illumination, improve the ability of a dentist to identify microscopic root canal orifices, which facilitates the efficient creation of conservative access openings with adequate straight-line access in maxillary molars. Magnified photos illustrate various microscopic anatomical structures or landmarks of the initial access opening. Techniques are explored for implementing an access opening for teeth with vital versus necrotic pulpal tissues. The article also explores the use of piezoelectric or ultrasonic instruments for revealing root canal orifices and for removing pulp stones or calcified pulpal tissue inside the pulp chamber. PMID:27403069

  13. Accuracy of Cameriere's cut-off value for third molar in assessing 18 years of age.

    PubMed

    De Luca, S; Biagi, R; Begnoni, G; Farronato, G; Cingolani, M; Merelli, V; Ferrante, L; Cameriere, R

    2014-02-01

    Due to increasingly numerous international migrations, estimating the age of unaccompanied minors is becoming of enormous significance for forensic professionals who are required to deliver expert opinions. The third molar tooth is one of the few anatomical sites available for estimating the age of individuals in late adolescence. This study verifies the accuracy of Cameriere's cut-off value of the third molar index (I3M) in assessing 18 years of age. For this purpose, a sample of orthopantomographs (OPTs) of 397 living subjects aged between 13 and 22 years (192 female and 205 male) was analyzed. Age distribution gradually decreases as I3M increases in both males and females. The results show that the sensitivity of the test was 86.6%, with a 95% confidence interval of (80.8%, 91.1%), and its specificity was 95.7%, with a 95% confidence interval of (92.1%, 98%). The proportion of correctly classified individuals was 91.4%. Estimated post-test probability, p was 95.6%, with a 95% confidence interval of (92%, 98%). Hence, the probability that a subject positive on the test (i.e., I3M<0.08) was 18 years of age or older was 95.6%. PMID:24365729

  14. The maxillary molar endodontic access opening: A microscope-based approach.

    PubMed

    Mamoun, John Sami

    2016-01-01

    This article reviews the basic clinical techniques of performing a maxillary molar endodontic access opening, starting from the initial access opening into the pulp chamber, to the point where a size #10 file has been advanced to the apices of all three or four (or more) canals. The article explains how the use of the dental surgical operating microscope or microscope-level loupes magnification of ×6-8 or greater, combined with head-mounted or coaxial illumination, improve the ability of a dentist to identify microscopic root canal orifices, which facilitates the efficient creation of conservative access openings with adequate straight-line access in maxillary molars. Magnified photos illustrate various microscopic anatomical structures or landmarks of the initial access opening. Techniques are explored for implementing an access opening for teeth with vital versus necrotic pulpal tissues. The article also explores the use of piezoelectric or ultrasonic instruments for revealing root canal orifices and for removing pulp stones or calcified pulpal tissue inside the pulp chamber. PMID:27403069

  15. [Distalization of the upper second molar: clinical case].

    PubMed

    Castaldo, A; Blasi, S; Vettese, P

    1991-01-01

    The Authors showed a clinical case in which has been put on a distalizing system together with a palatal bar between the first upper molars, a sectional placed between the first and the second molar and a 100 g precalibrated Sentalloy coil. PMID:1784297

  16. Understanding the current anatomical competence landscape: Comparing perceptions of program directors, residents, and fourth-year medical students.

    PubMed

    Fillmore, Erin P; Brokaw, James J; Kochhar, Komal; Nalin, Peter M

    2016-07-01

    A mixed methods survey of fourth-year medical students, resident physicians, and residency program directors at the Indiana University School of Medicine gathered perceptions of anatomical competence-defined as the anatomical education necessary for effective clinical practice. The survey items explored numerous aspects of anatomical competence, including the most effective modes of instruction, perceptions of readiness for clinical practice, and specific suggestions for improving anatomical education during medical school and residency. The response rate was 46% for fourth-year medical students, 47% for residents (as graduates from 137 medical schools), and 71% for program directors. A majority of students and residents reported that their course in Gross Anatomy prepared them well for clinical practice; that cadaveric dissection was important in the early development of their anatomical competence; and that placing a greater emphasis on clinical relevance in medical school would have improved their anatomical competence even further. However, in terms of anatomical preparedness upon entering residency, the program directors rated their residents less prepared than the residents rated themselves. All three groups agreed that there is need for additional opportunities for anatomical educational during medical school and residency. Suggestions for improving anatomical education included the following: providing more opportunities for cadaveric dissection during medical school and residency; more consistent teaching of anatomy for clinical practice; more workshops that review anatomy; and better integration of anatomy with the teaching of other subjects during medical school. Anat Sci Educ 9: 307-318. © 2015 American Association of Anatomists. PMID:26632977

  17. Collaborative regression-based anatomical landmark detection

    NASA Astrophysics Data System (ADS)

    Gao, Yaozong; Shen, Dinggang

    2015-12-01

    Anatomical landmark detection plays an important role in medical image analysis, e.g. for registration, segmentation and quantitative analysis. Among the various existing methods for landmark detection, regression-based methods have recently attracted much attention due to their robustness and efficiency. In these methods, landmarks are localised through voting from all image voxels, which is completely different from the classification-based methods that use voxel-wise classification to detect landmarks. Despite their robustness, the accuracy of regression-based landmark detection methods is often limited due to (1) the inclusion of uninformative image voxels in the voting procedure, and (2) the lack of effective ways to incorporate inter-landmark spatial dependency into the detection step. In this paper, we propose a collaborative landmark detection framework to address these limitations. The concept of collaboration is reflected in two aspects. (1) Multi-resolution collaboration. A multi-resolution strategy is proposed to hierarchically localise landmarks by gradually excluding uninformative votes from faraway voxels. Moreover, for informative voxels near the landmark, a spherical sampling strategy is also designed at the training stage to improve their prediction accuracy. (2) Inter-landmark collaboration. A confidence-based landmark detection strategy is proposed to improve the detection accuracy of ‘difficult-to-detect’ landmarks by using spatial guidance from ‘easy-to-detect’ landmarks. To evaluate our method, we conducted experiments extensively on three datasets for detecting prostate landmarks and head & neck landmarks in computed tomography images, and also dental landmarks in cone beam computed tomography images. The results show the effectiveness of our collaborative landmark detection framework in improving landmark detection accuracy, compared to other state-of-the-art methods.

  18. Mandibular third molar autotransplantation--literature review with clinical cases.

    PubMed

    Mendes, Rui Amaral; Rocha, Germano

    2004-12-01

    Autotransplantation of mandibular third molars in a precocious phase of development is indicated when a substitute for adjacent compromised or missing molars is needed, and when mesial movements of the posterior teeth, the resultant loss of space, and overeruption of opposing teeth and consequent changes in the occlusion must be avoided. Provided that the apices of the mandibular third molar are immature, the immediate replacement of a lost or compromised tooth usually ensures a good outcome. Transplantation of third molars helps to maintain alveolar bone and enables endosseous implantation without requiring bone regeneration. We present examples of transplantation of mandibular third molars and review the factors that affect the success or failure of this procedure, such as atraumatic extraction and adequate immobilization of the transplanted tooth and root development after transplantation. Sex or age seem to have no effect on the final outcome. PMID:15588551

  19. Image analysis of anatomical traits in stalk transections of maize and other grasses

    SciTech Connect

    Heckwolf, Sven; Heckwolf, Marlies; Kaeppler, Shawn M.; de Leon, Natalia; Spalding, Edgar P

    2015-04-09

    Grass stalks architecturally support leaves and reproductive structures, functionally support the transport of water and nutrients, and are harvested for multiple agricultural uses. Research on these basic and applied aspects of grass stalks would benefit from improved capabilities for measuring internal anatomical features. In particular, methods suitable for phenotyping populations of plants are needed.

  20. Nonsurgical Endodontic Management of a Molar-Incisor Malformation-affected Mandibular First Molar: A Case Report.

    PubMed

    Yue, Wonyoung; Kim, Euiseong

    2016-04-01

    A molar-incisor malformation (MIM) is a newly reported type of dental anomaly that involves a characteristic root malformation in permanent first molars and deciduous second molars and a crown defect in permanent central incisors. This case report describes a nonsurgical root canal treatment of a MIM-affected molar by aid of a reformatted axial view of the tooth cone-beam computed tomography (CBCT). A MIM-affected molar has calcified canal orifices and a few immature accessory furcal canals. Conventional root canal treatment with the aid of CBCT followed by resin restoration was performed on the tooth. The malformed roots of MIM teeth generally make it difficult to apply conventional endodontic treatment; however, it was possible to do with the aid of the reformatted axial view of the CBCT. PMID:26706790

  1. Anatomical Basis for the Cardiac Interventional Electrophysiologist

    PubMed Central

    Sánchez-Quintana, Damián; Doblado-Calatrava, Manuel; Cabrera, José Angel; Macías, Yolanda; Saremi, Farhood

    2015-01-01

    The establishment of radiofrequency catheter ablation techniques as the mainstay in the treatment of tachycardia has renewed new interest in cardiac anatomy. The interventional arrhythmologist has drawn attention not only to the gross anatomic details of the heart but also to architectural and histological characteristics of various cardiac regions that are relevant to the development or recurrence of tachyarrhythmias and procedural related complications of catheter ablation. In this review, therefore, we discuss some anatomic landmarks commonly used in catheter ablations including the terminal crest, sinus node region, Koch's triangle, cavotricuspid isthmus, Eustachian ridge and valve, pulmonary venous orifices, venoatrial junctions, and ventricular outflow tracts. We also discuss the anatomical features of important structures in the vicinity of the atria and pulmonary veins, such as the esophagus and phrenic nerves. This paper provides basic anatomic information to improve understanding of the mapping and ablative procedures for cardiac interventional electrophysiologists. PMID:26665006

  2. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars

    PubMed Central

    Kamburoğlu, Kıvanç; Tatar, İlkan; Arıkan, Volkan; Çelik, Hakan Hamdi; Yüksel, Selcen; Özen, Tuncer

    2015-01-01

    Purpose This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Materials and Methods Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. Results The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images. Conclusion Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth. PMID:26730367

  3. Replacement of a first molar and 3 second molars by the mesial inclination of 4 impacted third molars in an adult with a Class II Division 1 malocclusion.

    PubMed

    Tomonari, Hiroshi; Yagi, Takakazu; Kuninori, Takaharu; Ikemori, Takahiro; Miyawaki, Shouichi

    2015-06-01

    This case report presents the successful replacement of 1 first molar and 3 second molars by the mesial inclination of 4 impacted third molars. A woman, 23 years 6 months old, had a chief complaint of crowding of her anterior teeth and linguoclination of a second molar on the left side. The panoramic radiographic images showed that the maxillary and mandibular third molars on both sides were impacted. Root resorption on the distal surfaces of the maxillary second molars was suspected. The patient was given a diagnosis of Angle Class II Division 1 malocclusion with severe crowding of the anterior teeth and 4 impacted third molars. After we extracted the treated maxillary second premolars and the second molars on both sides, the treated mandibular second premolar and the second molar on the left side, and the root canal-filled mandibular first molar on the right side, the 4 impacted third molars were uprighted and formed part of the posterior functional occlusion. The total active treatment period was 39 months. The maxillary and mandibular third molars on both sides successfully replaced the first and second molars. The replacement of a damaged molar by an impacted third molar is a useful treatment option for using sound teeth. PMID:26038080

  4. Anatomic Considerations in Frontal Sinus Surgery.

    PubMed

    Folbe, Adam J; Svider, Peter F; Eloy, Jean Anderson

    2016-08-01

    Comprehension of the complex anatomic variants comprising the frontal sinus outflow tract is essential for successful surgical intervention. Deviation from sound technique increases the potential for a variety of deleterious sequelae, including recurrent disease as well as catastrophic intracranial and orbital injury. Furthermore, incomplete removal of elements occluding the frontal recess can result in severe stenosis that can increase the difficulty of further interventions. This review covers anatomic considerations that should be kept in mind when performing frontal sinus surgery. PMID:27329978

  5. Legal aspects.

    PubMed

    Escher, A

    1975-01-01

    The manufacture, application, use and disposal of fluorescent whitening agents (FWAs) may give rise to legal questions relating mainly to environmental protection and the effects on man and animals. In addition to legal aspects, certain commercial aspects such as the law of competition and the obligations of industry, including compensation for damage caused by FWAs, are discussed. PMID:1064546

  6. Quantitative prediction and molar description of the environment

    PubMed Central

    Baum, William M.

    1989-01-01

    Molecular explanations of behavior, based on momentary events and variables that can be measured each time an event occurs, can be contrasted with molar explanations, based on aggregates of events and variables that can be measured only over substantial periods of time. Molecular analyses cannot suffice for quantitative accounts of behavior, because the historical variables that determine behavior are inevitably molar. When molecular explanations are attempted, they always depend on hypothetical constructs that stand as surrogates for molar environmental variables. These constructs allow no quantitative predictions when they are vague, and when they are made precise, they become superfluous, because they can be replaced with molar measures. In contrast to molecular accounts of phenomena like higher responding on ratio schedules than interval schedules and free-operant avoidance, molar accounts tend to be simple and straightforward. Molar theory incorporates the notion that behavior produces consequences that in turn affect the behavior, the notion that behavior and environment together constitute a feedback system. A feedback function specifies the dependence of consequences on behavior, thereby describing properties of the environment. Feedback functions can be derived for simple schedules, complex schedules, and natural resources. A complete theory of behavior requires describing the environment's feedback functions and the organism's functional relations. Molar thinking, both in the laboratory and in the field, can allow quantitative prediction, the mark of a mature science. PMID:22478030

  7. [Establishment of anatomical terminology in Japan].

    PubMed

    Shimada, Kazuyuki

    2008-12-01

    The history of anatomical terminology in Japan began with the publication of Waran Naikei Ihan-teimŏ in 1805 and Chŏtei Kaitai Shinsho in 1826. Although the establishment of Japanese anatomical terminology became necessary during the Meiji era when many western anatomy books imported into Janan were translated, such terminology was not unified during this period and varied among translators. In 1871, Tsukumo Ono's Kaibŏgaku Gosen was published by the Ministry of Education. Although this book is considered to be the first anatomical glossary terms in Japan, its contents were incomplete. Overseas, the German Anatomical Society established a unified anatomical terminology in 1895 called the Basle Nomina Anatomica (B.N.A.). Based on this development, Kaibŏgaku Meishŭ which follows the BNA, by Buntarŏ Suzuki was published in 1905. With the subsequent establishment in 1935 of Jena Nomina Anatomica (J.N.A.), the unification of anatomical terminology was also accelerated in Japan, leading to the further development of terminology. PMID:19108488

  8. Strong links between genomic and anatomical diversity in both mammalian olfactory chemosensory systems.

    PubMed

    Garrett, Eva C; Steiper, Michael E

    2014-05-22

    Mammalian olfaction comprises two chemosensory systems: the odorant-detecting main olfactory system (MOS) and the pheromone-detecting vomeronasal system (VNS). Mammals are diverse in their anatomical and genomic emphases on olfactory chemosensation, including the loss or reduction of these systems in some orders. Despite qualitative evidence linking the genomic evolution of the olfactory systems to specific functions and phenotypes, little work has quantitatively tested whether the genomic aspects of the mammalian olfactory chemosensory systems are correlated to anatomical diversity. We show that the genomic and anatomical variation in these systems is tightly linked in both the VNS and the MOS, though the signature of selection is different in each system. Specifically, the MOS appears to vary based on absolute organ and gene family size while the VNS appears to vary according to the relative proportion of functional genes and relative anatomical size and complexity. Furthermore, there is little evidence that these two systems are evolving in a linked fashion. The relationships between genomic and anatomical diversity strongly support a role for natural selection in shaping both the anatomical and genomic evolution of the olfactory chemosensory systems in mammals. PMID:24718758

  9. Lingual Guttering Technique for Removal of Impacted Mandibular Third Molars

    PubMed Central

    Kale, Tejraj P; Pandit, Vikram S; Patil, Shankargouda; Pawar, Vivek; Shetty, Nisha

    2014-01-01

    Background: To assess the clinical feasibility of lingual bone guttering technique for surgical extraction of mandibular third molars. Materials and Methods: 20 patients with thick lingual cortical plate were included in the study. Surgical extraction of mandibular third molars by lingual bone guttering technique was performed in all the subjects. These subjects were evaluated for integrity of lingual cortical plate and sensation of lingual nerve postoperatively. Results: All extractions done by lingual bone guttering technique were clinically feasible to perform and no complications were seen. Conclusion: Lingual bone guttering technique can be used safely in extraction of mandibular third molars with thick lingual cortical plate. PMID:25214725

  10. Molar heat capacity and entropy of calcium metal

    USGS Publications Warehouse

    Hemingway, B.S.; Robie, R.A.; Chase, M.W.

    1997-01-01

    The heat capacity of calcium has been measured at 85 mean temperatures between T ??? 8 K and T ??? 369 K using an adiabatically-shielded calorimeter in an intermittent heating mode. At T = 298.15 K, the recommended values for the molar heat capacity, molar entropy, and molar enthalpy increment referred to T = 0 are (25.77 ?? 0.08) J??K-1??mol-1, (42.90 ?? 0.11) J??K-1??mol-1, and (5811 ?? 12) J??mol-1, respectively. The uncertainties are twice the standard deviation of the mean. ?? 1997 Academic Press Limited.

  11. Modification of uprighting spring for derotation of second molars.

    PubMed

    Mallikarjun, Vankre; Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Jaipal, Pyata Reddy

    2013-01-01

    One of the most efficient ways for the correction of rotated upper molars is derotation with a transpalatal arch, but this appliance is usually favourable when the need for correction is same on both sides of the dental arch. Derotation of unilateral upper second molar is a difficult task, especially when there is no accessible tooth/ any attachment is available distal to it for the application of couple forces. We have designed a modification of uprighting spring which is far more convenient than using the conventional method of TPA for derotation of unilateral upper second molar. PMID:24640073

  12. [BODIES ARTIFACTS AND ANATOMICAL MODELS].

    PubMed

    Aruta, Alessandro

    2015-01-01

    Through three different museological approaches, diachronically arranged, the essay intends to introduce some pertinent questions related to the topic of the conference "Bodies and Anatomy: the corpses in the museums from Ruysch to Von Hagens. The first item analyzes a recent line of British museological studies, treating mainly medical British museums of the XVIII and XIX century, with intriguing developments arriving up to nowadays. A second point illustrates several aspects with regards to the donation and the arrangement of the morbid specimina Luigi Gedda collection, coming from the CSS Mendel of Rome to the Museum of Pathological Anatomy of Sapienza University of Rome. Finally, in a crossover between the previous points, it will be presented some recent studies regarding the employment of new communication technologies in the scientific and medical museology. PMID:26946593

  13. Cone-beam computed tomography analysis of the vestibular surgical pathway to the palatine root of the maxillary first molar

    PubMed Central

    Kalender, Atakan; Aksoy, Umut; Basmaci, Fatma; Orhan, Kaan; Orhan, Ayse Isil

    2013-01-01

    Objective: The aim of this study was to evaluate the anatomical distance between apices of the palatine root of the maxillary first molars to the buccal bone plate to identify the vestibular surgical pathway in a Turkish adult population using cone-beam computed tomography (CBCT) images. Methods: CBCT scans of 107 (48 male and 59 female) patients were retrospectively analyzed. The overall mean age was 38.6 years. The distance between the vestibular cortex and vestibular side of the palatine root was measured for 192 maxillary first molars both on axial images parallel to the palatal plane and on reformatted cross-sectional images. A Pearson’s chi square test and Mann-Whitney U-test were performed to evaluate differences among age, localization, and measurements. Differences were considered statistically significant at P<.05. Results: The mean distance between the buccal cortex and the buccal side of the palatine root of the superior first molar in both male and female patients was 10.13 and 9.70 mm, respectively. The incidence of interposition of the lateral recess of the maxillary sinus between the roots was 42.2% and 49% in men and women, respectively. Statistically significant sex-related differences were found in the vestibular surgical pathway (P<.05). Conclusions: For precise planning of endodontic surgery, it is crucial to determine the exact dimensions and location of the periapical lesion, as well as its relationship with the roots and other neighboring anatomical structures. CBCT can be a powerful tool for the evaluation of surgical cases in three dimensions with less ionizing radiation and better avoidance of complications during surgery. PMID:23408714

  14. Caries Management Strategies for Primary Molars

    PubMed Central

    Santamaria, R.M.; Innes, N.P.T.; Machiulskiene, V.; Evans, D.J.P.; Splieth, C.H.

    2014-01-01

    Minimal invasive approaches to managing caries, such as partial caries removal techniques, are showing increasing evidence of improved outcomes over the conventional complete caries removal. There is also increasing interest in techniques where no caries is removed. We present the 1-yr results of clinical efficacy for 3 caries management options for occlusoproximal cavitated lesions in primary molars: conventional restorations (CR; complete caries removal and compomer restoration), Hall technique (HT; no caries removal, sealing in with stainless steel crowns), and nonrestorative caries treatment (NRCT; no caries removal, opening up the cavity, teaching brushing and fluoride application). In sum, 169 children (3-8 yr old; mean, 5.56 ± 1.45 yr) were enrolled in this secondary care–based, 3-arm, parallel-group, randomized clinical trial. Treatments were carried out by specialist pediatric dentists or postgraduate trainees. One lesion per child received CR, HT, or NRCT. Outcome measures were clinical failure rates, grouped as minor failure (restoration loss/need for replacement, reversible pulpitis, caries progression, etc.) and major failure (irreversible pulpitis, abscess, etc.). There were 148 children (87.6%) with a minimum follow-up of 11 mo (mean, 12.23 ± 0.98 mo). Twenty teeth were recorded as having at least 1 minor failure: NRCT, n = 8 (5%); CR, n = 11 (7%); HT, n = 1 (1%) (p = .002, 95% CI = 0.001 to 0.003). Only the comparison between NRCT and CR showed no significant difference (p = .79, 95% CI = 0.78 to 0.80). Nine (6%) experienced at least 1 major failure: NRCT, n = 4 (2%); CR, n = 5 (3%); HT, n = 0 (0%) (p = .002, 95% CI = 0.001 to 0.003). Individual comparison of NRCT and CR showed no statistically significant difference in major failures (p = .75, 95% CI = 0.73 to 0.76). Success and failure rates were not significantly affected by pediatric dentists’ level of experience (p = .13, 95% CI = 0.12 to 0.14). The HT was significantly more successful

  15. Reanalysis of the Lukeino molar (KNM-LU 335).

    PubMed

    Ungar, P S; Walker, A; Coffing, K

    1994-06-01

    This paper details a reanalysis of KNM-LU 335, a hominoid mandibular first molar dated to about 6 Ma from the Lukeino Formation, Kenya. Researchers have argued that this molar closely resembles those of modern chimpanzees and may approximate the ancestral morphotype of humans and chimpanzees. The investigation presented here describes a morphometric study of the Lukeino molar and M1s of Homo sapiens, Pan troglodytes, and early australopithecines. Results indicate that KNM-LU 335 differs from both human and chimpanzee M1s in relative distances (measured in three dimensions) between crown fissure termini. Further, the Lukeino molar shares with early australopithecines a pronounced flaring of the buccal surface of the crown not seen for either modern sample. Results of this study do not exclude KNM-LU 335 as a potential ancestral morphotype for Pan and Homo but provide no evidence that this morphotype resembled modern chimpanzees. PMID:8085609

  16. Determining Molar Combining Ratios Using Radioisotopes--A Student Experiment

    ERIC Educational Resources Information Center

    Sears, Jerry A.

    1976-01-01

    Outlines an experimental procedure in which an iodine radioisotope is used to determine molar combining ratios of lead and silver with the iodine. Tables and graphs show the definitive results that should be attainable. (CP)

  17. On the Etiology of Molar-Incisor Hypomineralization.

    PubMed

    Vieira, Alexandre R; Kup, Elaine

    2016-01-01

    Molar-incisor hypomineralization (MIH) is a condition that is defined based on its peculiar clinical presentation. Reports on the etiology of the condition and possible risk factors are inconclusive and the original suggestion that MIH is an idiopathic condition is often cited. Our group was the first to suggest MIH has a genetic component that involves genetic variation in genes expressed during dental enamel formation. In this report, we provide a rationale to explain the preferential affection of molars and incisors. We suggest that MIH is a genetic condition based on its prevalence, which varies depending on the geographic location, and the evidence that on occasion second primary molars, permanent canines, and premolars can show signs of hypomineralization of enamel when molars and incisors are affected. PMID:27111773

  18. A Multidisciplinary Approach for Managing Severely Malaligned Lower Molars.

    PubMed

    Keinan, David; Birnboim-Blaum, Galit; Webber, Mariel

    2016-01-01

    An impacted mandibular molar is a common clinical situation that may damage adjacent teeth and impair periodontal health. Improper treatment brings the risk of damaging adjacent vital tissues. The risk can be reduced by early diagnosis and extraction of the impacted tooth by an experienced clinician. However, in clinical cases of two impacted molars, it may be beneficial for the patient to save at least one molar. This can be achieved by orthodontic alignment of one of the molars, while extracting the other. The decision should be based upon prognosis and risks for each procedure and for both teeth. The case presented here demonstrates a recommended clinical decision-making process before treatment, followed by monitored multidisciplinary treatment with adaptations made as the treatment progresses. PMID:26939154

  19. Fusion or gemination? An unusual mandibular second molar.

    PubMed

    Camargo, Angela Jordão; Arita, Emiko Saito; Watanabe, Plauto Christopher Aranha

    2016-01-01

    Fusion and gemination is not an uncommon finding and affected most primary dentition and the permanent maxillary incisors. These changes can develop a series of complication. A 11-year-old male presented radiography finding: an unusual mandibular second molar. A well-documented case brings a challenge for radiologists classify between fusion and gemination. In conclusion, this alteration although common in other regions, there are no case in the literature involving "second and third" molar. PMID:26945485

  20. Treatment of a Maxillary First Molar with Two Palatal Roots

    PubMed Central

    Asghari, Vahideh; Rahimi, Saeed; Ghasemi, Negin; Talebzadeh, Bita; Norlouoni, Ahmad

    2015-01-01

    Thorough knowledge of the morphology and internal anatomy of the root canal system is essential, because it determines the successful outcome of endodontic treatment. The main goal of endodontic treatment is to prevent apical periodontitis and/or to promote the healing of periapical lesion. Presence of two canals or roots on the palatal side of the first maxillary molar has rarely been reported. This case report presents a maxillary first molar with two separate palatal roots. PMID:26523146

  1. The orthodontic extraction of permanent molars: a literature review.

    PubMed

    Chua, Emilia S L; Felicita, A Sumathi

    2015-05-01

    The most common cause of dental crowding is the presence of an arch-length--tooth-size discrepancy. Conventional methods of gaining space in orthodontics involve the extraction of teeth, often premolars. However, there are a number of clinical situations in which the extraction of permanent molars might be considered. This paper highlights the indications, advantages, disadvantages and timing of the extraction of the first, second and third permanent molars in the treatment of a crowded malocclusion. PMID:26219149

  2. Cervicothoracic Subcutaneous Emphysema and Pneumomediastinum After Third Molar Extraction.

    PubMed

    Picard, Maxime; Pham Dang, Nathalie; Mondie, Jean Michel; Barthelemy, Isabelle

    2015-12-01

    Third molar extraction is one of the most common interventions in dental and maxillofacial surgery. Complications are frequent and well documented, with swelling, pain, bleeding, infection, and lingual or alveolar nerve injury being the most common. This report describes a case of subcutaneous extensive emphysema and pneumomediastinum that occurred 4 days after extraction of an impacted right mandibular third molar. The management and etiology of this case and those reported in the literature are discussed. PMID:26341684

  3. Fusion or gemination? An unusual mandibular second molar

    PubMed Central

    Camargo, Angela Jordão; Arita, Emiko Saito; Watanabe, Plauto Christopher Aranha

    2015-01-01

    Fusion and gemination is not an uncommon finding and affected most primary dentition and the permanent maxillary incisors. These changes can develop a series of complication. A 11-year-old male presented radiography finding: an unusual mandibular second molar. A well-documented case brings a challenge for radiologists classify between fusion and gemination. In conclusion, this alteration although common in other regions, there are no case in the literature involving “second and third” molar. PMID:26945485

  4. Root canal morphology of South Asian Indian maxillary molar teeth

    PubMed Central

    Singh, Shishir; Pawar, Mansing

    2015-01-01

    Objective: The objective was to study the root canal morphology of South Asian Indian Maxillary molars using a tooth clearing technique. Materials and Methods: Hundred teeth each comprising of first, second, and third molars collected from different dental schools and clinics in India were subjected to standard dye penetration, decalcification and clearing procedure before being studied. Results: The first molar mesiobuccal roots exhibited 69% Type I, 24% Type II, 4% Type IV, 2% Type V, and 1% exhibited a Vertuccis Type VIII canal anatomy. In the group with three separate roots the second molar mesiobuccal roots in exhibited 80.6% Type I, 15.3% Type II, 2.7% Type IV, and 1.4% Type V canal anatomy while the third molars mesiobuccal roots exhibited 57.4% Type I, 32% Type II, 2.1% Type III, 8.5% Type IV, 1% had a Type V canal anatomy in the similar group. Conclusion: A varied root canal anatomy was seen in the mesiobuccal root canal of the maxillary molars. PMID:25713497

  5. Kissing molars extraction: Case series and review of the literature

    PubMed Central

    Arjona-Amo, Manuel; Torres-Carranza, Eusebio; Batista-Cruzado, Antonio; Serrera-Figallo, Maria-Angeles; Crespo-Torres, Santos; Belmonte-Caro, Rodolfo; Albisu-Andrade, Claudio; Gutiérrez-Pérez, José-Luis

    2016-01-01

    Kissing molars are a very rare form of inclusion defined as molars included in the same quadrant, with occlusal surfaces contacting each other within a single dental follicle. We present four cases of this pathology: a 35 year-old male, referred to the Oral and Maxillofacial Surgery Department of the Hospital Virgen del Rocio in Seville, and three females of 24, 26, and 31 years, all of which had kissing molars that were treated by tooth extraction. We have found only 10 cases published in the medical literature in which this type of inclusion is briefly described, none of which elaborate on the surgical technique employed. In these cases, the indication for surgery is established when there is a history of recurring infections or cystic lesions associated with dental inclusions. The extraction of kissing molars requires an exhaustive comprehension of the anatomy of the region involved, sufficiently developed surgical abilities, and an extensive planning process. Key words:Impacted molar, kissing molar, surgical extraction. PMID:26855716

  6. Standardised studies on Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM): a need.

    PubMed

    Elfrink, M E C; Ghanim, A; Manton, D J; Weerheijm, K L

    2015-06-01

    In November 2014, a review of literature concerning prevalence data of Molar Incisor Hypomineralisation (MIH) and Hypomineralised Second Primary Molars (HSPM) was performed. A search of PubMed online databases was conducted for relevant articles published until November 2014. The reference lists of all retrieved articles were hand-searched. Studies were included after assessing the eligibility of the full-text article. Out of 1078 manuscripts, a total of 157 English written publications were selected based on title and abstract. Of these 157, 60 were included in the study and allocated as 52 MIH and 5 HSPM, and 3 for both MIH and HSPM. These studies utilised the European Academy of Paediatric Dentistry judgment criteria, the modified index of developmental defects of enamel (mDDE) and self-devised criteria, and demonstrated a wide variation in the reported prevalence (MIH 2.9-44 %; HSPM 0-21.8 %). Most values mentioned were representative for specific areas. More studies were performed in cities compared with rural areas. A great variation was found in calibration methods, number of participants, number of examiners and research protocols between the studies. The majority of the prevalence studies also investigated possible aetiological factors. To compare MIH and HSPM prevalence and or aetiological data around the world, standardisation of such studies seems essential. Standardisation of the research protocol should include a clearly described sample of children (minimum number of 300 for prevalence and 1000 for aetiology studies) and use of the same calibration sets and methods whereas aetiological studies need to be prospective in nature. A standardised protocol for future MIH and HSPM prevalence and aetiology studies is recommended. PMID:25894247

  7. Standardized anatomic space for abdominal fat quantification

    NASA Astrophysics Data System (ADS)

    Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.

    2014-03-01

    The ability to accurately measure subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) from images is important for improved assessment and management of patients with various conditions such as obesity, diabetes mellitus, obstructive sleep apnea, cardiovascular disease, kidney disease, and degenerative disease. Although imaging and analysis methods to measure the volume of these tissue components have been developed [1, 2], in clinical practice, an estimate of the amount of fat is obtained from just one transverse abdominal CT slice typically acquired at the level of the L4-L5 vertebrae for various reasons including decreased radiation exposure and cost [3-5]. It is generally assumed that such an estimate reliably depicts the burden of fat in the body. This paper sets out to answer two questions related to this issue which have not been addressed in the literature. How does one ensure that the slices used for correlation calculation from different subjects are at the same anatomic location? At what anatomic location do the volumes of SAT and VAT correlate maximally with the corresponding single-slice area measures? To answer these questions, we propose two approaches for slice localization: linear mapping and non-linear mapping which is a novel learning based strategy for mapping slice locations to a standardized anatomic space so that same anatomic slice locations are identified in different subjects. We then study the volume-to-area correlations and determine where they become maximal. We demonstrate on 50 abdominal CT data sets that this mapping achieves significantly improved consistency of anatomic localization compared to current practice. Our results also indicate that maximum correlations are achieved at different anatomic locations for SAT and VAT which are both different from the L4-L5 junction commonly utilized.

  8. Anatomical variants and pathologies of the vermix

    PubMed Central

    Deshmukh, Swati; Verde, Franco; Johnson, Pamela T.; Fishman, Elliot K.

    2015-01-01

    The appendix may demonstrate a perplexing range of normal and abnormal appearances on imaging exams. Familiarity with the anatomy and anatomical variants of the appendix is helpful in identifying the appendix on ultrasound, computed tomography, and magnetic resonance imaging. Knowledge of the variety of pathologies afflicting the appendix and of the spectrum of imaging findings may be particularly useful to the emergency radiologist for accurate diagnosis and appropriate guidance regarding clinical and surgical management. In this pictorial essay, we review appendiceal embryology, anatomical variants such as Amyand hernias, and pathologies from appendicitis to carcinoid, mucinous, and nonmucinous epithelial neoplasms. PMID:24570122

  9. Anatomic considerations for central venous cannulation

    PubMed Central

    Bannon, Michael P; Heller, Stephanie F; Rivera, Mariela

    2011-01-01

    Central venous cannulation is a commonly performed procedure which facilitates resuscitation, nutritional support, and long-term vascular access. Mechanical complications most often occur during insertion and are intimately related to the anatomic relationship of the central veins. Working knowledge of surface and deep anatomy minimizes complications. Use of surface anatomic landmarks to orient the deep course of cannulating needle tracts appropriately comprises the crux of complication avoidance. The authors describe use of surface landmarks to facilitate safe placement of internal jugular, subclavian, and femoral venous catheters. The role of real-time sonography as a safety-enhancing adjunct is reviewed. PMID:22312225

  10. Anatomical Considerations on Surgical Anatomy of the Carotid Bifurcation

    PubMed Central

    Michalinos, Adamantios; Chatzimarkos, Markos; Arkadopoulos, Nikolaos; Safioleas, Michail

    2016-01-01

    Surgical anatomy of carotid bifurcation is of unique importance for numerous medical specialties. Despite extensive research, many aspects such as precise height of carotid bifurcation, micrometric values of carotid arteries and their branches as their diameter, length, and degree of tortuosity, and variations of proximal external carotid artery branches are undetermined. Furthermore carotid bifurcation is involved in many pathologic processes, atheromatous disease being the commonest. Carotid atheromatous disease is a major predisposing factor for disabling and possibly fatal strokes with geometry of carotid bifurcation playing an important role in its natural history. Consequently detailed knowledge of various anatomic parameters is of paramount importance not only for understanding of the disease but also for design of surgical treatment, especially selection between carotid endarterectomy and carotid stenting. Carotid bifurcation paragangliomas constitute unique tumors with diagnostic accuracy, treatment design, and success of operative intervention dependent on precise knowledge of anatomy. Considering those, it becomes clear that selection and application of proper surgical therapy should consider anatomical details. Further research might ameliorate available treatment options or even lead to innovative ones. PMID:27047690

  11. First molar health status in different craniofacial relationships

    PubMed Central

    Linjawi, Amal I

    2016-01-01

    Objective To investigate the association between the health status of permanent first molars and different craniofacial relationships among adolescents. Study design This is a retrospective study on patients’ records aged 11–15 years. Sex, skeletal relationship, vertical growth pattern, malocclusion, overjet, and overbite were assessed. The health status of permanent first molars was recorded from the orthopantomograms and intraoral photographs as “sound” and “not sound”. Chi-square, Mann–Whitney U and Kruskal–Wallis tests, and Pearson’s correlation coefficient were used to analyze and correlate the assessed variables. Significance level was set at P<0.05. Results A total of 210 records were evaluated; 81 were male, 68 had Class I and 91 had Class II skeletal relationships. More than half of the subjects had normal (n=67) to moderate deep bite (n=72); normal (n=91), moderately increased (n=54), to severely increased (n=50) overjet; and Class I (n=106) and Class II division 1 (n=75) malocclusion. Significant differences were found in the health status of the permanent first molars with respect to sex (P=0.034), vertical growth pattern (P=0.01), and overbite (P=0.047). Strong correlations were only found between the health status of the permanent first molars and the following variables: sex (P=0.036) and vertical growth pattern (P=0.004). Significant correlation was further found between the upper left first molar health status and sex (P=0.019) and the lower right first molar health status and the vertical growth pattern (P=0.001). No significant association was found with the anteroposterior craniofacial relationships (P>0.05). Conclusion Sex difference and vertical growth patterns were found to be potential predictors of the health status of the permanent first molars. No significant association was found with the anteroposterior craniofacial relationships. PMID:27462176

  12. Genetic integration of molar cusp size variation in baboons.

    PubMed

    Koh, Christina; Bates, Elizabeth; Broughton, Elizabeth; Do, Nicholas T; Fletcher, Zachary; Mahaney, Michael C; Hlusko, Leslea J

    2010-06-01

    Many studies of primate diversity and evolution rely on dental morphology for insight into diet, behavior, and phylogenetic relationships. Consequently, variation in molar cusp size has increasingly become a phenotype of interest. In 2007 we published a quantitative genetic analysis of mandibular molar cusp size variation in baboons. Those results provided more questions than answers, as the pattern of genetic integration did not fit predictions from odontogenesis. To follow up, we expanded our study to include data from the maxillary molar cusps. Here we report on these later analyses, as well as inter-arch comparisons with the mandibular data. We analyzed variation in two-dimensional maxillary molar cusp size using data collected from a captive pedigreed breeding colony of baboons, Papio hamadryas, housed at the Southwest National Primate Research Center. These analyses show that variation in maxillary molar cusp size is heritable and sexually dimorphic. We also estimated additive genetic correlations between cusps on the same crown, homologous cusps along the tooth row, and maxillary and mandibular cusps. The pattern for maxillary molars yields genetic correlations of one between the paracone-metacone and protocone-hypocone. Bivariate analyses of cuspal homologues on adjacent teeth yield correlations that are high or not significantly different from one. Between dental arcades, the nonoccluding cusps consistently yield high genetic correlations, especially the metaconid-paracone and metaconid-metacone. This pattern of genetic correlation does not immediately accord with the pattern of development and/or calcification, however these results do follow predictions that can be made from the evolutionary history of the tribosphenic molar. PMID:20034010

  13. Erupted complex odontoma delayed eruption of permanent molar.

    PubMed

    Ohtawa, Yumi; Ichinohe, Saori; Kimura, Eri; Hashimoto, Sadamitsu

    2013-01-01

    Odontomas, benign tumors that develop in the jaw, rarely erupt into the oral cavity. We report an erupted odontoma which delayed eruption of the first molar. The patient was a 10-year-old Japanese girl who came to our hospital due to delayed eruption of the right maxillary first molar. All the deciduous teeth had been shed. The second premolar on the right side had erupted, but not the first molar. Slight inflammation of the alveolar mucosa around the first molar had exposed a tooth-like, hard tissue. Panoramic radiography revealed a radiopaque mass indicating a lesion approximately 1 cm in diameter. The border of the image was clear, and part of the mass was situated close to the occlusal surface of the first molar. The root of the maxillary right first molar was only half-developed. A clinical diagnosis of odontoma was made. The odontoma was subsequently extracted, allowing the crown of the first molar to erupt almost 5 months later. The dental germ of the permanent tooth had been displaced by the odontoma. However, after the odontoma had been extracted, the permanent tooth was still able to erupt spontaneously, as eruptive force still remained. When the eruption of a tooth is significantly delayed, we believe that it is necessary to examine the area radiographically. If there is any radiographic evidence of a physical obstruction that might delay eruption, that obstruction should be removed before any problems can arise. Regular dental checkups at schools might improve our ability to detect evidence of delayed eruption earlier. PMID:24521551

  14. Genetic integration of molar cusp size variation in baboons

    PubMed Central

    Koh, Christina; Bates, Elizabeth; Broughton, Elizabeth; Do, Nicholas T.; Fletcher, Zachary; Mahaney, Michael C.; Hlusko, Leslea J.

    2010-01-01

    Many studies of primate diversity and evolution rely on dental morphology for insight into diet, behavior, and phylogenetic relationships. Consequently, variation in molar cusp size has increasingly become a phenotype of interest. In 2007 we published a quantitative genetic analysis of mandibular molar cusp size variation in baboons. Those results provided more questions than answers, as the pattern of genetic integration did not fit predictions from odontogenesis. To follow up, we expanded our study to include data from the maxillary molar cusps. Here we report on these later analyses, as well as inter-arch comparisons with the mandibular data. We analyzed variation in two-dimensional maxillary molar cusp size using data collected from a captive pedigreed breeding colony of baboons, Papio hamadryas, housed at the Southwest National Primate Research Center. These analyses show that variation in maxillary molar cusp size is heritable and sexually dimorphic. We also estimated additive genetic correlations between cusps on the same crown, homologous cusps along the tooth row, and maxillary and mandibular cusps. The pattern for maxillary molars yields genetic correlations of one between the paracone-metacone and protocone-hypocone. Bivariate analyses of cuspal homologues on adjacent teeth yield correlations that are high or not significantly different from one. Between dental arcades, the non-occluding cusps consistently yield high genetic correlations, especially the metaconid-paracone and metaconid-metacone. This pattern of genetic correlation does not immediately accord with the pattern of development and/or calcification, however these results do follow predictions that can be made from the evolutionary history of the tribosphenic molar. PMID:20034010

  15. Molar Intrusion in Open-bite Adults Using Zygomatic Miniplates.

    PubMed

    Marzouk, Eiman S; Abdallah, Essam Mohamed; El-Kenany, Walid A

    2015-01-01

    The aim of this study is to evaluate the skeletal, dental and soft tissue changes that arise after intrusion of the maxillary molars using zygomatic miniplates in adult skeletal anterior open bite patients. In addition to measuring the amount and rate of molar intrusion; with special emphasis on changes in the axial inclination of the intruded molars. The study group was composed of 13 anterior open bite patients (mean age 18 years, 8 months ± 2 years, 2 months) with posterior dentoalveolar excess. Mini-plates were placed in the zygomatic buttress bilaterally. The upper arch was segmentally leveled and a double Trans-Palatal Arch (TPA) was bonded. Closed NiTi coil spring was placed bilaterally between the book of the mini-plate just mesial and distal to the first molar buccal tube applying intrusive force of 450 gper side. Lateral and posteroanterior cephalograms were taken before intrusion (T1: post upper segmental leveling) and after intrusion (T2). Comparison between means before and after the intrusion was done using Wilcoxon Signed Ranks test (WSRT). Mandibular autorotation followed the molar intrusion, SNB and SN-Pog angles significantly increased while the ANB, MP-SN angle and N-S-Gn angle significantly decreased. The mean amount of accomplished molar intrusion was 3.1mm ± 0.74mm, with a rate of 0.36mm per month ± 0.08mm per month and a bite closure of 6.55mm ± 1.83mm. There was no significant buccal tip in the right and left molars upon intrusion. Conclusion: Miniplates zygomatic anchorage can be used effectively for skeletal open bite correction through posterior dento-alveolar intrusion. Intrusion of the posterior teeth with skeletal anchorage induced counterclockwise rotation of the mandible and, as a consequence, corrected the anteroposterior intermaxillary relationship with a dramatic improvement in the facial soft tissue convexity. PMID:26349291

  16. Effect of anatomic, semi-anatomic and non-anatomic occlusal surface tooth preparations on the adaptation of zirconia copings

    PubMed Central

    Asiri, Waleed; Hefne, Mohammed Jameel

    2014-01-01

    PURPOSE To compare the accuracy of marginal and internal adaptation of zirconia (Zr) copings fabricated on anatomic (A), semi-anatomic (SA) and non-anatomic (NA) occlusal surface preparations. MATERIALS AND METHODS 45 extracted bicuspid teeth were prepared for receiving zirconia crowns, with different occlusal preparation designs A=15, SA=15 & NA=15. The Zr copings were fabricated by using CAD4DENT, CAD/CAM. The copings were adjusted, cemented and were cross sectioned centrally from buccal cusp tip to lingual cusp tip into mesial and distal halves. The copings were examined under electron microscope at ×200 magnification and the measurements were recorded at 9 predetermined areas in micrometers. RESULTS Overall mean gap values for the three groups was found to be 155.93±33.98 µm with Anatomical Occlusal preparation design having the least gap value of 139.23±30.85 µm showing the best adaptation among the groups. Post Hoc Tukey's test showed a statistically significant difference (P=.007) between the means of gap for A & NA preparation designs. Measurements recorded at 9 predetermined points showed variations for the three groups. CONCLUSION Anatomical occlusal preparation designs resulted in better marginal and internal adaptation of Zr copings. There is a considerable variation between the measured marginal and internal gap values for the Zr copings fabricated by the (CAD4DENT-CAD/CAM). This variation may be associated with the lack of standardization of the preparation of teeth, computerized designing of the coping for each tooth, cement used, uniform pressure application during the cementation of the copings, sectioning of the copings and the microscopic measurements. PMID:25551003

  17. Anatomic Variant of Liver, Gall Bladder and Inferior Vena Cava

    PubMed Central

    Gladwin, V.; Chand, Parkash

    2016-01-01

    The morphology and relations of liver, gall bladder and inferior vena cava are cardinal. Their anatomical variations may be a reason for the adverse surgical outcome. During routine anatomy dissection of an abdomen, we noticed a variant liver, gall bladder and inferior vena cava in a 63-year-old male cadaver. In the specimen, a retrohepatic segment of inferior vena cava was found to be intrahepatic. On dissection, it was observed that inferior vena cava was covered entirely by a liver tissue on its dorsal aspect. In the same specimen, the gall bladder had undulated inferior surface. On dissection of the gall bladder, numerous mucosal folds were present in the interior. A band of fibrous tissue was found, which was extending from the right side of the gall bladder to the falciform ligament. Hence, preoperative scanning of congenital variations of the liver, gall bladder and inferior vena cava may be compassionate in planning safe surgeries and interventional abdominal procedures.

  18. Evolution of the Anatomical Theatre in Padova

    ERIC Educational Resources Information Center

    Macchi, Veronica; Porzionato, Andrea; Stecco, Carla; Caro, Raffaele

    2014-01-01

    The anatomical theatre played a pivotal role in the evolution of medical education, allowing students to directly observe and participate in the process of dissection. Due to the increase of training programs in clinical anatomy, the Institute of Human Anatomy at the University of Padova has renovated its dissecting room. The main guidelines in…

  19. HPV Vaccine Effective at Multiple Anatomic Sites

    Cancer.gov

    A new study from NCI researchers finds that the HPV vaccine protects young women from infection with high-risk HPV types at the three primary anatomic sites where persistent HPV infections can cause cancer. The multi-site protection also was observed at l

  20. Giving Ourselves: The Ethics of Anatomical Donation

    ERIC Educational Resources Information Center

    Gunderman, Richard B.

    2008-01-01

    In some European countries, such as Italy, medical education is threatened by a dearth of anatomical specimens. Such a shortage could spread to other nations, including the United States. This article addresses two ethical questions in body donation. Why might people choose to donate their bodies to education and science? What sorts of ethical…

  1. Requirement of alveolar bone formation for eruption of rat molars.

    PubMed

    Wise, Gary E; He, Hongzhi; Gutierrez, Dina L; Ring, Sherry; Yao, Shaomian

    2011-10-01

    Tooth eruption is a localized event that requires a dental follicle (DF) to regulate the resorption of alveolar bone to form an eruption pathway. During the intra-osseous phase of eruption, the tooth moves through this pathway. The mechanism or motive force that propels the tooth through this pathway is controversial but many studies have shown that alveolar bone growth at the base of the crypt occurs during eruption. To determine if this bone growth (osteogenesis) was causal, experiments were designed in which the expression of an osteogenic gene in the DF, bone morphogenetic protein-6 (Bmp6), was inhibited by injection of the first mandibular molar of the rat with a small interfering RNA (siRNA) targeted against Bmp6. The injection was followed by electroporation to promote uptake of the siRNA. In 45 first molars injected, eruption was either delayed or completely inhibited (seven molars). In the impacted molars, an eruption pathway formed but bone growth at the base of the crypt was greatly reduced compared with the erupted first-molar controls. These studies show that alveolar bone growth at the base of the crypt is required for tooth eruption and that Bmp6 may be essential for promoting this growth. PMID:21896048

  2. Requirement of alveolar bone formation for eruption of rat molars

    PubMed Central

    Wise, Gary E.; He, Hongzhi; Gutierrez, Dina L.; Ring, Sherry; Yao, Shaomian

    2011-01-01

    Tooth eruption is a localized event that requires a dental follicle (DF) to regulate the resorption of alveolar bone to form an eruption pathway. During the intra-osseous phase of eruption, the tooth moves through this pathway. The mechanism or motive force that propels the tooth through this pathway is controversial but many studies have shown that alveolar bone growth at the base of the crypt occurs during eruption. To determine if this bone growth (osteogenesis) was causal, experiments were designed in which the expression of an osteogenic gene in the DF, bone morphogenetic protein-6 (BMP6), was inhibited by injection of the 1st mandibular molar of the rat with an siRNA targeted against BMP6. The injection was followed by electroporation to promote uptake of the siRNA. In 45 first molars injected, eruption either was delayed or completely inhibited (7 molars). In the impacted molars, an eruption pathway formed but bone growth at the base of the crypt was greatly reduced as compared to the erupted first molar controls. These studies show that alveolar bone growth at the base of the crypt is required for tooth eruption and that BMP6 may be an essential gene for promoting this growth. PMID:21896048

  3. Orthodontic band retention on primary molar stainless steel crowns.

    PubMed

    Beemer, R L; Ferracane, J L; Howard, H E

    1993-01-01

    The retention of orthodontic bands cemented on primary molar stainless steel crowns (SSC) was studied in vitro. Unitek maxillary and mandibular 1st and 2nd primary molar SSC were fitted with one of four commonly used orthodontic bands (Unitek regular, Unitek narrow, Rocky Mountain, or custom bands made from SSC) using glass ionomer cement. The cemented samples were tested for their resistance to dislodgment on the Instron Universal Testing Machine (Instron Engineering Corp., Canton, MA) in tensile mode. Alpha level for statistical significance was set at alpha = 0.05. Unitek regular bands cemented on the 2nd molar crowns and Unitek narrow bands cemented on the 1st molar crown samples had equivalent or superior resistance to dislodgment compared with the other bands in the study. When the inside of the band and the outside band-bearing surfaces of selected crowns were lightly scored with a diamond bur prior to cementation, samples exhibited significantly superior retention. Subgroup means increased from 107 to 330%, compared to the values obtained in their preroughened state. The mean values obtained using the roughened band/crown interface technique (range 52.9 +/- 7.6 to 73.6 +/- 8.4 lbs) compared favorably with retention values from the literature for orthodontic bands cemented on permanent molar and premolar teeth. PMID:8153003

  4. Aberration in the palatal root of the maxillary first molar

    PubMed Central

    Rajalbandi, Sandeep; Shingte, Sandhya Narayan; Sundaresh, K J; Mallikarjuna, Rachappa

    2013-01-01

    Thorough knowledge of root canal morphology is essential for the endodontic therapy. Variations in the root and root canal morphology, especially in multirooted teeth, are a constant challenge for diagnosis and management. The dentist needs to be familiar with the various root canal configurations and their variations for successful endodontic therapy. There are rare variations in canal number and configuration in maxillary molars, which could affect treatment outcome. Two lingual root structures are occasionally found on human permanent maxillary molars. One of these is the normal lingual root, which is always present, the other is a supernumerary structure which can be located either mesiolingually (radix mesiolingualis) or distolingually (radix distolingualis). The purpose of this paper is to review the literature and to demonstrate a case report which describes the successful non-surgical endodontic management of an unusual maxillary first molar with four separate roots and four canals. PMID:23632609

  5. Pendulum Therapy of Molar Distalization in Mixed Dentition.

    PubMed

    Patil, Raju Umaji; Prakash, Amit; Agarwal, Anshu

    2016-01-01

    Early and timely pedo-orthodontic treatment is aimed at eliminating the disturbances of skeletal or dentoalveolar development, to harmonize the stomatognathic system before the full eruption of all permanent teeth. The advantages of pendulum appliance are its minimal dependence on patient's compliance (child cooperation), ease of fabrication, onetime activation and adjustment of the springs if necessary to correct minor transverse and vertical molar positions. This article reports a successful treatment method of class II malocclusion with pendulum appliance in mixed dentition phase. Distalization of maxillary molar was done, followed by guidance of canine impaction orthodontically and other dental correction using 0.022 MBT appliances. Posttreatment results were stable and remarkable. How to cite this article: Patil RU, Prakash A, Agarwal A. Pendulum Therapy of Molar Distalization in Mixed Dentition. Int J Clin Pediatr Dent 2016;9(1):67-73. PMID:27274159

  6. Pendulum Therapy of Molar Distalization in Mixed Dentition

    PubMed Central

    Prakash, Amit; Agarwal, Anshu

    2016-01-01

    ABSTRACT Early and timely pedo-orthodontic treatment is aimed at eliminating the disturbances of skeletal or dentoalveolar development, to harmonize the stomatognathic system before the full eruption of all permanent teeth. The advantages of pendulum appliance are its minimal dependence on patient’s compliance (child cooperation), ease of fabrication, onetime activation and adjustment of the springs if necessary to correct minor transverse and vertical molar positions. This article reports a successful treatment method of class II malocclusion with pendulum appliance in mixed dentition phase. Distalization of maxillary molar was done, followed by guidance of canine impaction orthodontically and other dental correction using 0.022 MBT appliances. Posttreatment results were stable and remarkable. How to cite this article: Patil RU, Prakash A, Agarwal A. Pendulum Therapy of Molar Distalization in Mixed Dentition. Int J Clin Pediatr Dent 2016;9(1):67-73. PMID:27274159

  7. Radicular anatomy of permanent mandibular second molars in an Iranian population: A preliminary study

    PubMed Central

    Akhlaghi, Nahid M.; Abbas, Fatemeh Mashadi; Mohammadi, Mostafa; Shamloo, Mohammad Reza Karami; Radmehr, Orkideh; Kaviani, Ramin; Rakhshan, Vahid

    2016-01-01

    Background: Root morphology is of utmost importance to endodontic sciences. Since there are a few studies on the morphology of mandibular second molars' roots, and some anatomical variables are not evaluated before, the aim of this study was to investigate thoroughly radicular anatomy of this tooth. Materials and Methods: This ex vivo study was performed on 150 intact mandibular second molars. After access cavity preparation and ensuring canal patency, Indian ink was injected into root canals from the orifices. The teeth became transparent using methyl salicylate storage. Then, they were inspected by an endodontist under a ×10 stereomicroscope regarding numerous root morphological variables. Data were analyzed using chi-square test and analysis of variance (α = 0.05). Results: About 86.7% of teeth had two roots and 13.3% were single-rooted (P = 0.0001), of which, 50% were C-shaped (6.7% of all teeth, P = 0.0001). 86.7% of mesial roots were double canalled, whereas 75.3% of distal roots were single canalled (P = 0.0001). 71.45% and 95.3% of the mesial and distal roots had one apical foramen, respectively (P = 0.0001). Apical foramens were mostly central followed by lingual in most cases. Distances between apical foramen and apical constriction ranged between 0.27 and 0.40 mm (P = 0.0545). Distances between apical foramen and root apices ranged between 0.30 and 0.47 mm (P = 0.0001). Vertucci classifications of mesial canals were Type II in 62.6% and Type IV in 37.4%. 86.2% of single-canal distal roots were Type I. 66.7% of double-canal distal roots were Type II and 33.3% were Type IV (P = 0.0001). The mean root lengths from cervical to apex of mesial, distal, and single roots were 14.02 ± 0.85 (95% confidence interval [CI] = 13.87–14.17), 13.35 ± 0.91 (95% CI = 13.19–13.50), and 14.25 ± 0.72 mm (95% CI = 13.91–14.58), respectively. The extents of canal curvatures varied between 20° and 31° buccolingually (P = 0.0000), and between 19° and 27

  8. Sex assessment by molar odontometrics in North Indian population

    PubMed Central

    Narang, Ramandeep Singh; Manchanda, Adesh S.; Singh, Balwinder

    2015-01-01

    Introduction: Human identification is based on scientific principles, mainly involving dental records, fingerprints, estimation of age, postmortem reports, differentiation by blood groups, and DNA comparisons. Sex assessment is one of the prime factors employed to assist with the identification of an individual. Aims and Objective: To investigate univariate sex differences in the dimensions of permanent first molars and to assess sex, based on buccolingual (BL) and mesiodistal (MD) dimensions of permanent first molars in a population of north India. In addition, the study intended to evaluate the reliability of dimensional variation of these teeth in assessment of sex among the population. Materials and Methods: The study sample consists of 410 adult individuals (200 males and 210 females), from a north Indian population. The BL and MD diameters of the permanent first molars were measured using digital vernier callipers. Results: It was observed statistically significant difference between males and females with P < 0.05, in maxillary casts in both BL and MD dimensions; but only in the MD dimension in mandibular casts. A high level of sexual dimorphism of 7.7% was found in the BL dimension of the maxillary right first molar. The accuracy of sex assessment by each dimension was deliberated by univariate analyses with an overall accuracy ranging from 67.5 to 88% for various dimensions. Conclusion: Sexual dimorphism of teeth is population specific and among north Indian population, BL and MD dimensions in maxillary first molar and MD dimension in mandibular first molar can be used for sex assessment. PMID:25709321

  9. Molar enamel thickness and dentine horn height in Gigantopithecus blacki.

    PubMed

    Olejniczak, A J; Smith, T M; Wang, W; Potts, R; Ciochon, R; Kullmer, O; Schrenk, F; Hublin, J-J

    2008-01-01

    Absolutely thick molar enamel is consistent with large body size estimates and dietary inferences about Gigantopithecus blacki, which focus on tough or fibrous vegetation. In this study, 10 G. blacki molars demonstrating various stages of attrition were imaged using high-resolution microtomography. Three-dimensional average enamel thickness and relative enamel thickness measurements were recorded on the least worn molars within the sample (n = 2). Seven molars were also virtually sectioned through the mesial cusps and two-dimensional enamel thickness and dentine horn height measurements were recorded. Gigantopithecus has the thickest enamel of any fossil or extant primate in terms of absolute thickness. Relative (size-scaled) measures of enamel thickness, however, support a thick characterization (i.e., not "hyper-thick"); G. blacki relative enamel thickness overlaps slightly with Pongo and completely with Homo. Gigantopithecus blacki dentine horns are relatively short, similar to (but shorter than) those of Pongo, which in turn are shorter than those of humans and African apes. Gigantopithecus blacki molar enamel (and to a lesser extent, that of Pongo pygmaeus) is distributed relatively evenly across the occlusal surface compared with the more complex distribution of enamel thickness in Homo sapiens. The combination of evenly distributed occlusal enamel and relatively short dentine horns in G. blacki results in a flat and low-cusped occlusal surface suitable to grinding tough or fibrous food objects. This suite of molar morphologies is also found to varying degrees in Pongo and Sivapithecus, but not in African apes and humans, and may be diagnostic of subfamily Ponginae. PMID:17941103

  10. Historical evolution of anatomical terminology from ancient to modern.

    PubMed

    Sakai, Tatsuo

    2007-06-01

    The historical development of anatomical terminology from the ancient to the modern can be divided into five stages. The initial stage is represented by the oldest extant anatomical treatises by Galen of Pergamon in the Roman Empire. The anatomical descriptions by Galen utilized only a limited number of anatomical terms, which were essentially colloquial words in the Greek of this period. In the second stage, Vesalius in the early 16th century described the anatomical structures in his Fabrica with the help of detailed magnificent illustrations. He coined substantially no anatomical terms, but devised a system that distinguished anatomical structures with ordinal numbers. The third stage of development in the late 16th century was marked by innovation of a large number of specific anatomical terms especially for the muscles, vessels and nerves. The main figures at this stage were Sylvius in Paris and Bauhin in Basel. In the fourth stage between Bauhin and the international anatomical terminology, many anatomical textbooks were written mainly in Latin in the 17th century, and in modern languages in the 18th and 19th centuries. Anatomical terms for the same structure were differently expressed by different authors. The last stage began at the end of the 19th century, when the first international anatomical terminology in Latin was published as Nomina anatomica. The anatomical terminology was revised repeatedly until the current Terminologia anatomica both in Latin and English. PMID:17585563

  11. Anatomical calibration for wearable motion capture systems: Video calibrated anatomical system technique.

    PubMed

    Bisi, Maria Cristina; Stagni, Rita; Caroselli, Alessio; Cappello, Angelo

    2015-08-01

    Inertial sensors are becoming widely used for the assessment of human movement in both clinical and research applications, thanks to their usability out of the laboratory. This work aims to propose a method for calibrating anatomical landmark position in the wearable sensor reference frame with an ease to use, portable and low cost device. An off-the-shelf camera, a stick and a pattern, attached to the inertial sensor, compose the device. The proposed technique is referred to as video Calibrated Anatomical System Technique (vCAST). The absolute orientation of a synthetic femur was tracked both using the vCAST together with an inertial sensor and using stereo-photogrammetry as reference. Anatomical landmark calibration showed mean absolute error of 0.6±0.5 mm: these errors are smaller than those affecting the in-vivo identification of anatomical landmarks. The roll, pitch and yaw anatomical frame orientations showed root mean square errors close to the accuracy limit of the wearable sensor used (1°), highlighting the reliability of the proposed technique. In conclusion, the present paper proposes and preliminarily verifies the performance of a method (vCAST) for calibrating anatomical landmark position in the wearable sensor reference frame: the technique is low time consuming, highly portable, easy to implement and usable outside laboratory. PMID:26077101

  12. Detection and management of a complex canal configuration in mesiobuccal root of maxillary first molar using three dimensional imaging.

    PubMed

    Deepa, Velagala L; Bollu, Indira Priyadharsini; Dhamaraju, Bhargavi; Yadla, Padmasri

    2016-04-01

    This case report discusses the identification and management of complex canal configuration of 3-2-1 in the mesiobuccal (MB) root of the maxillary left first molar. Careful attention to details of the pulpal floor and applying the knowledge of the laws of orifice location along with deepening the subpulpal groove with ultrasonic tips helped in identifying the three MB canals. Manual scouting helped in understanding the anatomic configuration; the use of three-dimensional imaging technique and spiral computed tomography (SCT) confirmed the same. SCT images showed buccolingually wide and bulbous mesiobuccal root with three separate canals at coronal third that merged into two canals in the middle and exited as a single canal at the apex. This article highlights the role of SCT in three-dimensionally analyzing the unseen rarest canal configurations that ultimately enabled the clinician to thoroughly explore, debride, and obturate the entire root canal system. PMID:27195233

  13. Detection and management of a complex canal configuration in mesiobuccal root of maxillary first molar using three dimensional imaging

    PubMed Central

    Deepa, Velagala L.; Bollu, Indira Priyadharsini; Dhamaraju, Bhargavi; Yadla, Padmasri

    2016-01-01

    This case report discusses the identification and management of complex canal configuration of 3-2-1 in the mesiobuccal (MB) root of the maxillary left first molar. Careful attention to details of the pulpal floor and applying the knowledge of the laws of orifice location along with deepening the subpulpal groove with ultrasonic tips helped in identifying the three MB canals. Manual scouting helped in understanding the anatomic configuration; the use of three-dimensional imaging technique and spiral computed tomography (SCT) confirmed the same. SCT images showed buccolingually wide and bulbous mesiobuccal root with three separate canals at coronal third that merged into two canals in the middle and exited as a single canal at the apex. This article highlights the role of SCT in three-dimensionally analyzing the unseen rarest canal configurations that ultimately enabled the clinician to thoroughly explore, debride, and obturate the entire root canal system. PMID:27195233

  14. Procedures to recover DNA from pre-molar and molar teeth of decomposed cadavers with different post-mortem intervals.

    PubMed

    Raimann, Paulo E; Picanço, Juliane B; Silva, Deborah S B S; Albuquerque, Trícia C K; Paludo, Francis Jackson O; Alho, Clarice S

    2012-11-01

    A task-force to resolve 26 pending forensic caseworks was carried out. We tested four different protocols to extract DNA from molar and pre-molar teeth from 26 cadavers with post-mortem intervals from 2 months to 12 years. We compared the amount of DNA and DNA profiles with the time elapsed between death and laboratory procedures. Molar or pre-molar teeth were removed from the corpses, cleaned, and DNA was extracted using 2 or 12h of incubation on lysis buffer and filtered using concentration column or precipitated with isopropanol. DNA profiles were obtained using PowerPlex16™ System PCR Amplification Kit, AmpFlSTR(®) Yfiler™ and/or mtDNA sequencing. Complete DNA profiles comparison and statistical evaluation allowed unambiguous identification of the 26 victims. No significant differences were observed in the amount of DNA obtained with the distinct incubation times. The use of concentration column resulted in an increased amount of DNA when compared to isopropanol. However, the lower concentration of DNA obtained with isopropanol seemed to have been compensated by the higher purity. No significant differences in the number of amplified loci were found. A non-significant tendency was found between the amount of total DNA recovered and the time elapsed between death and laboratory procedures. The increase of post-mortem time did not interfere in the analysed autosomal loci. In conclusion, molar and pre-molar teeth were shown to be good candidates to obtain satisfactory DNA profiles, suggesting the high potential of tooth samples as source for DNA typing independently of the decomposed corpse's time or laboratory procedures. PMID:23040740

  15. Integrating anatomical pathology to the healthcare enterprise.

    PubMed

    Daniel-Le Bozec, Christel; Henin, Dominique; Fabiani, Bettina; Bourquard, Karima; Ouagne, David; Degoulet, Patrice; Jaulent, Marie-Christine

    2006-01-01

    For medical decisions, healthcare professionals need that all required information is both correct and easily available. We address the issue of integrating anatomical pathology department to the healthcare enterprise. The pathology workflow from order to report, including specimen process and image acquisition was modeled. Corresponding integration profiles were addressed by expansion of the IHE (Integrating the Healthcare Enterprise) initiative. Implementation using respectively DICOM Structured Report (SR) and DICOM Slide-Coordinate Microscopy (SM) was tested. The two main integration profiles--pathology general workflow and pathology image workflow--rely on 13 transactions based on HL7 or DICOM standard. We propose a model of the case in anatomical pathology and of other information entities (orders, image folders and reports) and real-world objects (specimen, tissue samples, slides, etc). Cases representation in XML schemas, based on DICOM specification, allows producing DICOM image files and reports to be stored into a PACS (Picture Archiving and Communication System. PMID:17108550

  16. Detection of environmental effects through anatomic pathology.

    PubMed

    Miller, R W

    1985-01-01

    Anatomic pathology has produced considerable knowledge about environmental teratogens and carcinogens. A special disease registry established by a pathologist provided details of the association between oral contraceptives and hepatic neoplams. Pathologists were also involved in establishing in the link between diethylstilbestrol use and clear-cell adenocarcinomas of the vagina. An area of particular interest has been gender and ethnic differences in the incidence of certain diseases. Pathologists further make use of animal studies to investigate the pathogenesis of human tumors. Finally, stored serum or tissue is often used by pathologists to help diagnose diseases retrospectively. Human skin fibroblasts grown in culture and stored have been especially valuable for laboratory research. This chapter briefly highlights some of the milestones in the detection of enviromental effects through anatomic pathology. PMID:2997598

  17. Anatomic pathology laboratory information systems: a review.

    PubMed

    Park, Seung Lyung; Pantanowitz, Liron; Sharma, Gaurav; Parwani, Anil Vasdev

    2012-03-01

    The modern anatomic pathology laboratory depends on a reliable information infrastructure to register specimens, record gross and microscopic findings, regulate laboratory workflow, formulate and sign out report(s), disseminate them to the intended recipients across the whole health system, and support quality assurance measures. This infrastructure is provided by the Anatomical Pathology Laboratory Information Systems (APLIS), which have evolved over decades and now are beginning to support evolving technologies like asset tracking and digital imaging. As digital pathology transitions from "the way of the future" to "the way of the present," the APLIS continues to be one of the key effective enablers of the scope and practice of pathology. In this review, we discuss the evolution, necessary components, architecture and functionality of the APLIS that are crucial to today's practicing pathologist and address the demands of emerging trends on the future APLIS. PMID:22313836

  18. The Computerized Anatomical Man (CAM) model

    NASA Technical Reports Server (NTRS)

    Billings, M. P.; Yucker, W. R.

    1973-01-01

    A computerized anatomical man (CAM) model, representing the most detailed and anatomically correct geometrical model of the human body yet prepared, has been developed for use in analyzing radiation dose distribution in man. This model of a 50-percentile standing USAF man comprises some 1100 unique geometric surfaces and some 2450 solid regions. Internal body geometry such as organs, voids, bones, and bone marrow are explicitly modeled. A computer program called CAMERA has also been developed for performing analyses with the model. Such analyses include tracing rays through the CAM geometry, placing results on magnetic tape in various forms, collapsing areal density data from ray tracing information to areal density distributions, preparing cross section views, etc. Numerous computer drawn cross sections through the CAM model are presented.

  19. Quantifying anatomical shape variations in neurological disorders.

    PubMed

    Singh, Nikhil; Fletcher, P Thomas; Preston, J Samuel; King, Richard D; Marron, J S; Weiner, Michael W; Joshi, Sarang

    2014-04-01

    We develop a multivariate analysis of brain anatomy to identify the relevant shape deformation patterns and quantify the shape changes that explain corresponding variations in clinical neuropsychological measures. We use kernel Partial Least Squares (PLS) and formulate a regression model in the tangent space of the manifold of diffeomorphisms characterized by deformation momenta. The scalar deformation momenta completely encode the diffeomorphic changes in anatomical shape. In this model, the clinical measures are the response variables, while the anatomical variability is treated as the independent variable. To better understand the "shape-clinical response" relationship, we also control for demographic confounders, such as age, gender, and years of education in our regression model. We evaluate the proposed methodology on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database using baseline structural MR imaging data and neuropsychological evaluation test scores. We demonstrate the ability of our model to quantify the anatomical deformations in units of clinical response. Our results also demonstrate that the proposed method is generic and generates reliable shape deformations both in terms of the extracted patterns and the amount of shape changes. We found that while the hippocampus and amygdala emerge as mainly responsible for changes in test scores for global measures of dementia and memory function, they are not a determinant factor for executive function. Another critical finding was the appearance of thalamus and putamen as most important regions that relate to executive function. These resulting anatomical regions were consistent with very high confidence irrespective of the size of the population used in the study. This data-driven global analysis of brain anatomy was able to reach similar conclusions as other studies in Alzheimer's disease based on predefined ROIs, together with the identification of other new patterns of deformation. The

  20. Endoscopic Ankle Lateral Ligament Graft Anatomic Reconstruction.

    PubMed

    Michels, Frederick; Cordier, Guillaume; Guillo, Stéphane; Stockmans, Filip

    2016-09-01

    Chronic instability is a common complication of lateral ankle sprains. If nonoperative treatment fails, a surgical repair or reconstruction may be indicated. Today, endoscopic techniques to treat ankle instability are becoming more popular. This article describes an endoscopic technique, using a step-by-step approach, to reconstruct the ATFL and CFL with a gracilis graft. The endoscopic technique is reproducible and safe with regard to the surrounding anatomic structures. Short and midterm results confirm the benefits of this technique. PMID:27524711

  1. Absence of multiple premolars and ankylosis of deciduous molar with cant of the occlusal plane treated using skeletal anchorage.

    PubMed

    Farret, Marcel M; Farret, Milton M B

    2015-01-01

    Ankylosis and the absence of premolars are two relatively common conditions encountered in the field of orthodontics. However, the absence of multiple premolars, particularly two adjacent premolars, along with ankylosis of deciduous teeth, is unusual. Herein, we present a case report and discuss some aspects related to these abnormalities. A 15-year-old boy was missing the upper right first and second premolars and the lower right and left second premolars. In addition, the deciduous lower left second molar was ankylosed and in infraocclusion, causing canting of the occlusal plane. The patient was treated with a mini-implant to correct the Class II malocclusion on the left side and a miniplate to correct the cant of the occlusal plan. After treatment, the upper right space was kept closed, with the canine in contact with the first molar, and the lower left space was opened to an implant-prosthetic rehabilitation. PMID:24901068

  2. Engineering anatomically shaped human bone grafts

    PubMed Central

    Grayson, Warren L.; Fröhlich, Mirjam; Yeager, Keith; Bhumiratana, Sarindr; Chan, M. Ete; Cannizzaro, Christopher; Wan, Leo Q.; Liu, X. Sherry; Guo, X. Edward; Vunjak-Novakovic, Gordana

    2009-01-01

    The ability to engineer anatomically correct pieces of viable and functional human bone would have tremendous potential for bone reconstructions after congenital defects, cancer resections, and trauma. We report that clinically sized, anatomically shaped, viable human bone grafts can be engineered by using human mesenchymal stem cells (hMSCs) and a “biomimetic” scaffold-bioreactor system. We selected the temporomandibular joint (TMJ) condylar bone as our tissue model, because of its clinical importance and the challenges associated with its complex shape. Anatomically shaped scaffolds were generated from fully decellularized trabecular bone by using digitized clinical images, seeded with hMSCs, and cultured with interstitial flow of culture medium. A bioreactor with a chamber in the exact shape of a human TMJ was designed for controllable perfusion throughout the engineered construct. By 5 weeks of cultivation, tissue growth was evidenced by the formation of confluent layers of lamellar bone (by scanning electron microscopy), markedly increased volume of mineralized matrix (by quantitative microcomputer tomography), and the formation of osteoids (histologically). Within bone grafts of this size and complexity cells were fully viable at a physiologic density, likely an important factor of graft function. Moreover, the density and architecture of bone matrix correlated with the intensity and pattern of the interstitial flow, as determined in experimental and modeling studies. This approach has potential to overcome a critical hurdle—in vitro cultivation of viable bone grafts of complex geometries—to provide patient-specific bone grafts for craniofacial and orthopedic reconstructions. PMID:19820164

  3. A cervical ectopic masquerading as a molar pregnancy.

    PubMed

    Masir, N; Tamby, M R; Jamil, M A

    2000-03-01

    We report a case of cervical pregnancy complicated by life threatening hemorrhage. An initial diagnosis of molar pregnancy was made preoperatively. During uterine evacuation she developed profuse hemorrhage which required an emergency hysterectomy for uncontrolled bleeding. Histopathological examination confirmed a cervical pregnancy. The clinical and pathological criteria for the diagnosis and the etiology of cervical pregnancy are discussed. PMID:11072500

  4. Anterior tympanic plate fracture following extraction of the lower molar

    PubMed Central

    2016-01-01

    The present case report describes an external auditory canal injury following extraction of the lower molar. The external auditory canal was torn in the same fashion that occurs in an anterior tympanic plate fracture. This case demonstrates one of the rare complications associated with dental extractions. PMID:26904496

  5. Intrusion of overerupted molars by corticotomy and magnets.

    PubMed

    Hwang, H S; Lee, K H

    2001-08-01

    Although posterior tooth intrusion in an adult patient is a difficult procedure, it can be achieved without extruding the adjacent teeth by performing a corticotomy and using magnets. In carrying out this procedure on 2 adult patients whose molars had overerupted due to the early loss of antagonists, tooth movement was rapidly achieved without discomfort or side effects. PMID:11500664

  6. Management of Six Root Canals in Mandibular First Molar

    PubMed Central

    Gomes, Fabio de Almeida; Sousa, Bruno Carvalho

    2015-01-01

    Success in root canal treatment is achieved after thorough cleaning, shaping, and obturation of the root canal system. This clinical case describes conventional root canal treatment of an unusual mandibular first molar with six root canals. The prognosis for endodontic treatment in teeth with abnormal morphology is unfavorable if the clinician fails to recognize extra root canals. PMID:25685156

  7. The effect of dexamethasone on neurapraxia following third molar surgery.

    PubMed

    Von Arx, D P; Simpson, M T

    1989-12-01

    A double blind, controlled trial was undertaken to assess the effect of intra-muscular dexamethasone on neurapraxia following the surgical removal of mandibular third molars. No significant difference was found 24 h post-operatively between a control group and a group given dexamethasone. PMID:2597658

  8. Survival rates of porcelain molar crowns-an update.

    PubMed

    Kassem, Amr Shebl; Atta, Osama; El-Mowafy, Omar

    2010-01-01

    The aim of this study was to identify recent studies that dealt with the clinical performance of porcelain molar crowns and to explore the possibility of grouping the findings from similar studies together to draw overall conclusions. A MEDLINE literature search was conducted in early 2009 covering the preceding 12 years. Seventeen studies were indentified. However, only seven met the specific inclusion criteria and were analyzed. Among seven studies, five European countries were covered. Five studies reported on Procera AllCeram molar crowns while one reported on In-Ceram Alumina and Spinell crowns and another on CEREC crowns. For comparison, one additional study that reported on premolar crowns was included. In the five Procera AllCeram studies, 235 molar crowns were evaluated for 5 or more years, of which 24 failed. When the results of the five studies on the performance of Procera AllCeram molar crowns were considered collectively, an overall failure rate of 10.2% was found at 5 or more years. Int J Prosthodont 2010;23:60-62. PMID:20234895

  9. Non-compliance Appliances for Upper Molar Distalization: An Overview.

    PubMed

    Noorollahian, Saeed; Alavi, Shiva; Shirban, Farinaz

    2015-01-01

    Tooth Size Arch-length Discrepancy (TSALD) is a common problem in orthodontics. Its clinical signs are tooth crowding, impaction and incisor proclination. The treatment options are dental arch expansion or tooth mass reduction (stripping or extraction). The "extraction versus non-extraction" controversy has been widely debated in the orthodontic literature. Distalization is a kind of arch expansion in anetro-posterior dimension. Several studies have evaluated both the therapeutic effectiveness and the side effects of the appliances for this method of space gaining. In some cases molar distalization is preferred, e.g., a patient with acceptable profile and skeletal pattern and half cusp Class II molar malocclusion or even less. In some cases molar distalization is the only way, e.g., the patient with previous upper premolar extraction and excessive overijet, or a skeletal Class III patient with previous upper premolar extraction needed upper anterior teeth retraction to create reverse overjet aspre surgical orthodontic decompensation. In this review article, we described non-compliance upper molar distalizing appliances. PMID:26720949

  10. A Time for Heresy: A Molar Reading Model.

    ERIC Educational Resources Information Center

    Williamson, Leon E.

    A survey of the literature concerning the mental processes used in reading reveals a proliferation of molecular theories which explain only a small (and frequently neurological) component of the reading act. Enough information exists, however, to sketch an integrated, molar model of the reading process, which stresses the interrelationships…

  11. Determination of sexual dimorphism via maxillary first molar teeth in Himachali population

    PubMed Central

    Singla, Swati; Gupta, Rakhi; Puri, Abhiney; Bansal, Sucheta; Singla, Smita; Nangia, Rajat

    2015-01-01

    Context: Sex determination of skeletal remains forms part of archaeological and medicolegal examinations. It is an aspect of forensic odontology. Forensic odontology primarily deals with identification, based on recognition of unique features present in an individual's dental structures. Correct sex determination limits the pool of missing persons to just one half of the population. Aim of Study: Purpose of this study is to evaluate the existence of sexual dimorphism and variation in left and right maxillary first molars using bucco-lingual and mesio-distal dimensions in population of Sirmour District, H.P. Materials and Methods: Base sample comprised 100 subjects (50 males and 50 females) of an age group ranging from 17 to 25 years. Statistical Analysis Used: Unpaired t-test. Results: It was observed that the comparison of mean values of bucco-lingual and mesio-distal parameters showed highly statistically significant differences between males and females, measured both intraorally and on study casts. There were no significant differences between the mean values of both the parameters on the left side as compared to right side. Conclusion: The study concludes that sexual dimorphism is population specific. Among Himachali people, mesio-distal dimensions and bucco-lingual dimensions of first molar can aid in sex determination. PMID:26005295

  12. Human cochlea: anatomical characteristics and their relevance for cochlear implantation.

    PubMed

    Rask-Andersen, Helge; Liu, Wei; Erixon, Elsa; Kinnefors, Anders; Pfaller, Kristian; Schrott-Fischer, Annelies; Glueckert, Rudolf

    2012-11-01

    This is a review of the anatomical characteristics of human cochlea and the importance of variations in this anatomy to the process of cochlear implantation (CI). Studies of the human cochlea are essential to better comprehend the physiology and pathology of man's hearing. The human cochlea is difficult to explore due to its vulnerability and bordering capsule. Inner ear tissue undergoes quick autolytic changes making investigations of autopsy material difficult, even though excellent results have been presented over time. Important issues today are novel inner ear therapies including CI and new approaches for inner ear pharmacological treatments. Inner ear surgery is now a reality, and technical advancements in the design of electrode arrays and surgical approaches allow preservation of remaining structure/function in most cases. Surgeons should aim to conserve cochlear structures for future potential stem cell and gene therapies. Renewal interest of round window approaches necessitates further acquaintance of this complex anatomy and its variations. Rough cochleostomy drilling at the intricate "hook" region can generate intracochlear bone-dust-inducing fibrosis and new bone formation, which could negatively influence auditory nerve responses at a later time point. Here, we present macro- and microanatomic investigations of the human cochlea viewing the extensive anatomic variations that influence electrode insertion. In addition, electron microscopic (TEM and SEM) and immunohistochemical results, based on specimens removed at surgeries for life-threatening petroclival meningioma and some well-preserved postmortal tissues, are displayed. These give us new information about structure as well as protein and molecular expression in man. Our aim was not to formulate a complete description of the complex human anatomy but to focus on aspects clinically relevant for electric stimulation, predominantly, the sensory targets, and how surgical atraumaticity best could be

  13. Corticotomy-assisted molar protraction with the aid of temporary anchorage device.

    PubMed

    Uribe, Flavio; Janakiraman, Nandakumar; Fattal, Amine N; Schincaglia, Gian Pietro; Nanda, Ravindra

    2013-11-01

    This case report describes the interdisciplinary management of a 58-year-old woman who was missing lower first molars and supraerupted maxillary first molars. The treatment plan included intrusion of the upper first molars and corticotomy-assisted mandibular second molar protraction with the aid of temporary anchorage devices. Miniscrews were effective in intrusion of the maxillary first molars and protraction of the lower second molars. Although good functional outcome was achieved in 41 months, the corticotomy-assisted procedure did not significantly reduce the treatment time. PMID:23834274

  14. Cone Beam Computed Tomographic Evaluation and Diagnosis of Mandibular First Molar with 6 Canals

    PubMed Central

    Pasha, Shiraz; Chaitanya, Bathula Vimala; Somisetty, Kusum Valli

    2016-01-01

    Root canal treatment of tooth with aberrant root canal morphology is very challenging. So thorough knowledge of both the external and internal anatomy of teeth is an important aspect of root canal treatment. With the advancement in technology it is imperative to use modern diagnostic tools such as magnification devices, CBCT, microscopes, and RVG to confirm the presence of these aberrant configurations. However, in everyday endodontic practice, clinicians have to treat teeth with atypical configurations for root canal treatment to be successful. This case report presents the management of a mandibular first molar with six root canals, four in mesial and two in distal root, and also emphasizes the use and importance of Cone Beam Computed Tomography (CBCT) as a diagnostic tool in endodontics. PMID:26904310

  15. The anatomical diaspora: evidence of early American anatomical traditions in North Dakota.

    PubMed

    Stubblefield, Phoebe R

    2011-09-01

    The current focus in forensic anthropology on increasing scientific certainty in ancestry determination reinforces the need to examine the ancestry of skeletal remains used for osteology instruction. Human skeletal remains were discovered on the University of North Dakota campus in 2007. After recovery, the osteological examination resulted in a profile for a 33- to 46-year-old woman of African descent with stature ranging from 56.3 to 61.0 in. The pattern of postmortem damage indicated that the remains had been prepared for use as an anatomical teaching specimen. Review of the American history of anatomical teaching revealed a preference for Black subjects, which apparently extended to states like North Dakota despite extremely low resident populations of people of African descent. This study emphasizes the need to examine the ancestry of older teaching specimens that lack provenience, rather than assuming they are derived from typical (i.e., Indian) sources of anatomical material. PMID:21447074

  16. Anatomical organization of the rat organum vasculosum laminae terminalis.

    PubMed

    Prager-Khoutorsky, Masha; Bourque, Charles W

    2015-08-15

    The organum vasculosum of the laminae terminalis (OVLT) is a circumventricular organ located along the ventral part of the anterior wall of the third ventricle. Because it lacks a complete blood-brain barrier (BBB), blood-borne signals detected in the OVLT provide the brain with information from the periphery and contribute to the generation of centrally mediated responses to humoral feedback and physiological stressors. Experimental studies on the rat OVLT are hindered by a poor understanding of its precise anatomical dimensions and cellular organization. In this study, we use histological techniques to characterize the spatial outline of the rat OVLT and to examine the location of neurons, astrocytes, tanycytes, and ependymocytes within its confines. Our data reveal that OVLT neurons are embedded in a dense network of tanycyte processes. Immunostaining against the neuronal marker NeuN revealed that neurons are distributed throughout the OVLT, except for a thick midline septum, which comprises densely packed cells of unknown function or lineage. Moreover, the most ventral aspect of the OVLT is devoid of neurons and is occupied by a dense network of glial cell processes that form a thick layer between the neurons and the pial surface on the ventral aspect of the nucleus. Lastly, combined detection of NeuN and c-Fos protein following systemic injection of hypertonic NaCl revealed that neurons responsive to this stimulus are located along the entire midline core of the OVLT, extending from its most anterior ventral aspect to the more caudally located "dorsal cap" region. PMID:26017494

  17. Piezoelectric Versus Conventional Rotary Techniques for Impacted Third Molar Extraction

    PubMed Central

    Jiang, Qian; Qiu, Yating; Yang, Chi; Yang, Jingyun; Chen, Minjie; Zhang, Zhiyuan

    2015-01-01

    Abstract Impacted third molars are frequently encountered in clinical work. Surgical removal of impacted third molars is often required to prevent clinical symptoms. Traditional rotary cutting instruments are potentially injurious, and piezosurgery, as a new osteotomy technique, has been introduced in oral and maxillofacial surgery. No consistent conclusion has been reached regarding whether this new technique is associated with fewer or less severe postoperative sequelae after third molar extraction. The aim of this study was to compare piezosurgery with rotary osteotomy techniques, with regard to surgery time and the severity of postoperative sequelae, including pain, swelling, and trismus. We conducted a systematic literature search in the Cochrane Library, PubMed, Embase, and Google Scholar. The eligibility criteria of this study included the following: the patients were clearly diagnosed as having impacted mandibular third molars; the patients underwent piezosurgery osteotomy, and in the control group rotary osteotomy techniques, for removing impacted third molars; the outcomes of interest include surgery time, trismus, swelling or pain; the studies are randomized controlled trials. We used random-effects models to calculate the difference in the outcomes, and the corresponding 95% confidence interval. We calculated the weighted mean difference if the trials used the same measurement, and a standardized mean difference if otherwise. A total of seven studies met the eligibility criteria and were included in our analysis. Compared with rotary osteotomy, patients undergoing piezosurgery experienced longer surgery time (mean difference 4.13 minutes, 95% confidence interval 2.75–5.52, P < 0.0001). Patients receiving the piezoelectric technique had less swelling at postoperative days 1, 3, 5, and 7 (all Ps ≤0.023). Additionally, there was a trend of less postoperative pain and trismus in the piezosurgery groups. The number of included randomized controlled

  18. TOPICAL REVIEW: Anatomical imaging for radiotherapy

    NASA Astrophysics Data System (ADS)

    Evans, Philip M.

    2008-06-01

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  19. Exploring metameric variation in human molars: a morphological study using morphometric mapping.

    PubMed

    Morita, Wataru; Morimoto, Naoki; Ohshima, Hayato

    2016-09-01

    Human molars exhibit a type of metameric variation, which is the difference in serially repeated morphology within an organism. Various theories have been proposed to explain how this variation is brought about in the molars. Actualistic data that support the theories, however, are still relatively scarce because of methodological limitations. Here we propose new methods to analyse detailed tooth crown morphologies. We applied morphometric mapping to the enamel-dentine junction of human maxillary molars and examined whether odontogenetic models were adaptable to human maxillary molars. Our results showed that the upper first molar is phenotypically distinct among the maxillary molars. The average shape of the upper first molar is characterized by four well-defined cusps and precipitous surface relief of the occlusal table. On the other hand, upper third molar is characterized by smooth surface relief of the occlusal table and shows greater shape variation and distinct distribution patterns in morphospace. The upper second molar represents an intermediate state between first and third molar. Size-related shape variation was investigated by the allometric vector analysis, and it appeared that human maxillary molars tend to converge toward the shape of the upper first molar as the size increases. Differences between the upper first molar and the upper second and third molar can thus be largely explained as an effect of allometry. Collectively, these results indicate that the observed pattern of metameric variation in human molars is consistent with odontogenetic models of molar row structure (inhibitory cascade model) and molar crown morphology (patterning cascade model). This study shows that morphometric mapping is a useful tool to visualize and quantify the morphological features of teeth, which can provide the basis for a better understanding of tooth evolution linking morphology and development. PMID:27098351

  20. [Sigismund Laskowski and his anatomical preparations technique].

    PubMed

    Gryglewski, Ryszard W

    2015-01-01

    Fixation of the entire bodies or individual organs, and later as well tissues and cellular structures, was and still is often a challenge for anatomists and histologists. Technique that combines extensive knowledge of natural sciences, as well as technical skills, was by those best researchers as Frederik Ruysch, brought to perfection. Preparations, if done with care and talent, are really propelling progress in anatomical studies and determining the quality of education for medical students and young physicians. And as it is true for many of today's medical disciplines and natural sciences, the nineteenth century was in many ways a breaking point for preparatory techniques in the realm of anatomy and histology. Among those who have achieved success, earning notoriety during their lifetime and often going into the annals of European most distinguished scholars were some Polish names: Louis Maurice Hirschfeld, whose preparations of the nervous system earned him well-deserved, international fame, Louis Charles Teichmann, who was the very first so precisely describing the lymphatic system and a creator of unique injection mass, Henry Kadyi, known for his outstanding preparations, especially of vascular system. Henry Frederick Hoyer sen., who was one of the first to use formalin regularly for accurate microscopic preparations, is seen by many as the founder of the Polish histology. In this group of innovators and precursors of modern preparation techniques place should be reserved for Zygmunt (Sigismund) Laskowski, Polish patriot, fighting in January Uprising, later an immigrant, a professor at the university sequentially Paris and Geneva. Acclaimed author of anatomical tables and certainly creator of one of the groundbreaking techniques in anatomical preparations. Based after many years of research on the simple glycerine-phenol mixture achieved excellent results both in fixation of entire bodies and organs or tissues. Quality of those preparations was as high and

  1. Regulatory aspects

    NASA Astrophysics Data System (ADS)

    Stern, Arthur M.

    1986-07-01

    At this time, there is no US legislation that is specifically aimed at regulating the environmental release of genetically engineered organisms or their modified components, either during the research and development stage or during application. There are some statutes, administered by several federal agencies, whose language is broad enough to allow the extension of intended coverage to include certain aspects of biotechnology. The one possible exception is FIFRA, which has already brought about the registration of several natural microbial pesticides but which also has provision for requiring the registration of “strain improved” microbial pesticides. Nevertheless, there may be gaps in coverage even if all pertinent statutes were to be actively applied to the control of environmental release of genetically modified substances. The decision to regulate biotechnology under TSCA was justified, in part, on the basis of its intended role as a gap-filling piece of environmental legislation. The advantage of regulating biotechnology under TSCA is that this statute, unlike others, is concerned with all media of exposure (air, water, soil, sediment, biota) that may pose health and environmental hazards. Experience may show that extending existing legislation to regulate biotechnology is a poor compromise compared to the promulgation of new legislation specifically designed for this purpose. It appears that many other countries are ultimately going to take the latter course to regulate biotechnology.

  2. Effects of anatomical constraints on tumor growth

    NASA Astrophysics Data System (ADS)

    Capogrosso Sansone, B.; Delsanto, P. P.; Magnano, M.; Scalerandi, M.

    2001-08-01

    Competition for available nutrients and the presence of anatomical barriers are major determinants of tumor growth in vivo. We extend a model recently proposed to simulate the growth of neoplasms in real tissues to include geometrical constraints mimicking pressure effects on the tumor surface induced by the presence of rigid or semirigid structures. Different tissues have different diffusivities for nutrients and cells. Despite the simplicity of the approach, based on a few inherently local mechanisms, the numerical results agree qualitatively with clinical data (computed tomography scans of neoplasms) for the larynx and the oral cavity.

  3. Anatomic Locking Plate Fixation for Scaphoid Nonunion

    PubMed Central

    Yeung, Just; Sapienza, Anthony

    2016-01-01

    Nonunion can occur relatively frequently after scaphoid fracture and appears to be associated with severity of injury. There have been a number of techniques described for bone grafting with or without screw fixation to facilitate fracture healing. However, even with operative fixation of scaphoid fractures with bone grafting nonunion or malunion rates of 5 to 10 percent are still reported. This is the first report of an anatomic locking plate for scaphoid fracture repair in a 25-year-old right hand dominant healthy male. PMID:27366338

  4. Jugular foramen: anatomic and computed tomographic study

    SciTech Connect

    Daniels, D.L.; Williams, A.L.; Haughton, V.M.

    1984-01-01

    The computed tomographic (CT) appearance of the jugular foramen was examined in detail, and anatomic and CT sections were correlated. The pars nervosa and pars vascularis were identified, and, with intravenous contrast enhancement, a rapid sequence of scans at a gantry angle of +30/sup 0/ to the canthomeatal line demonstrated cranial nerves IX, X, and XI. The osseous margins of the jugular foramen were best shown by CT at planes of sections parallel and positive (0/sup 0/-30/sup 0/) to the canthomeatal line. CT can be used to evaluate osseous anatomy and the jugular foramen with precision sufficient to confidently exclude an intracanalicular mass.

  5. Human vs model observers in anatomic backgrounds

    NASA Astrophysics Data System (ADS)

    Eckstein, Miguel P.; Abbey, Craig K.; Whiting, James S.

    1998-04-01

    Model observers have been compared to human performance detecting low contrast signals in a variety of computer generated background including white noise, correlated noise, lumpy backgrounds, and two component noise. The purpose of the present paper is to extend this work by comparing a cumber of previously proposed model observers to human visual detection performance in real anatomic backgrounds. Human and model observer performance are compared as a function of increasing added white noise. Our results show that three of the four models are good predictors of human performance.

  6. Ectopic 3rd Molar Tooth in the Maxillary Antrum

    PubMed Central

    Bello, Seidu A.; Oketade, Ifeoluwa O.; Osunde, Otasowie D.

    2014-01-01

    Location of ectopic tooth in a nondentate area like the maxillary antrum is rare. A 17-year-old boy, with one year history of recurrent right facial swelling and radiographic finding of a maxillary third molar tooth located at the posterior wall of the maxillary antrum, is presented. Under endotracheal intubation, the tooth was extracted through a Caldwell-Luc antrostomy approach and patient had an uneventful recovery and has been symptom free for eight months. Ectopic tooth in the maxillary antrum is rare and is commonest with maxillary third molar. It may be symptomless but is more commonly associated with inflammatory symptoms. The treatment of choice is surgical excision which is mostly carried out with Caldwell-Luc approach, even though endoscopic approach is being reported. PMID:25132999

  7. Thermal correction to the molar polarizability of a Boltzmann gas

    SciTech Connect

    Jentschura, U. D.; Puchalski, M.; Mohr, P. J.

    2011-12-15

    Metrology in atomic physics has been crucial for a number of advanced determinations of fundamental constants. In addition to very precise frequency measurements, the molar polarizability of an atomic gas has recently also been measured very accurately. Part of the motivation for the measurements is due to ongoing efforts to redefine the International System of Units (SI), for which an accurate value of the Boltzmann constant is needed. Here we calculate the dominant shift of the molar polarizability in an atomic gas due to thermal effects. It is given by the relativistic correction to the dipole interaction, which emerges when the probing electric field is Lorentz transformed into the rest frame of the atoms that undergo thermal motion. While this effect is small when compared to currently available experimental accuracy, the relativistic correction to the dipole interaction is much larger than the thermal shift of the polarizability induced by blackbody radiation.

  8. Thermal correction to the molar polarizability of a Boltzmann gas

    NASA Astrophysics Data System (ADS)

    Jentschura, U. D.; Puchalski, M.; Mohr, P. J.

    2011-12-01

    Metrology in atomic physics has been crucial for a number of advanced determinations of fundamental constants. In addition to very precise frequency measurements, the molar polarizability of an atomic gas has recently also been measured very accurately. Part of the motivation for the measurements is due to ongoing efforts to redefine the International System of Units (SI), for which an accurate value of the Boltzmann constant is needed. Here we calculate the dominant shift of the molar polarizability in an atomic gas due to thermal effects. It is given by the relativistic correction to the dipole interaction, which emerges when the probing electric field is Lorentz transformed into the rest frame of the atoms that undergo thermal motion. While this effect is small when compared to currently available experimental accuracy, the relativistic correction to the dipole interaction is much larger than the thermal shift of the polarizability induced by blackbody radiation.

  9. Ectopic 3rd molar tooth in the maxillary antrum.

    PubMed

    Bello, Seidu A; Oketade, Ifeoluwa O; Osunde, Otasowie D

    2014-01-01

    Location of ectopic tooth in a nondentate area like the maxillary antrum is rare. A 17-year-old boy, with one year history of recurrent right facial swelling and radiographic finding of a maxillary third molar tooth located at the posterior wall of the maxillary antrum, is presented. Under endotracheal intubation, the tooth was extracted through a Caldwell-Luc antrostomy approach and patient had an uneventful recovery and has been symptom free for eight months. Ectopic tooth in the maxillary antrum is rare and is commonest with maxillary third molar. It may be symptomless but is more commonly associated with inflammatory symptoms. The treatment of choice is surgical excision which is mostly carried out with Caldwell-Luc approach, even though endoscopic approach is being reported. PMID:25132999

  10. Extrusion of impacted mandibular second molar using removable appliance

    PubMed Central

    Karthikeyan, M. K.; Prabhakar, Ramachandran; Saravanan, R.; Vikram, N. Raj; Kumar, R. Vinoth; Prasath, R. Eshwara

    2014-01-01

    The purpose of this article is to review the principles of case management of impacted mandibular molars and to illustrate their potential to respond well to treatment. Although the scope of treatment may be influenced by the patient's age, past dental history, severity of impaction, dentoalveolar development, and root form, the case reports demonstrate the inherent potential for good treatment outcome even in the most unfavorable circumstances. PMID:25210378

  11. Fate of the molar dental lamina in the monophyodont mouse.

    PubMed

    Dosedělová, Hana; Dumková, Jana; Lesot, Hervé; Glocová, Kristýna; Kunová, Michaela; Tucker, Abigail S; Veselá, Iva; Krejčí, Pavel; Tichý, František; Hampl, Aleš; Buchtová, Marcela

    2015-01-01

    The successional dental lamina (SDL) plays an essential role in the development of replacement teeth in diphyodont and polyphyodont animals. A morphologically similar structure, the rudimental successional dental lamina (RSDL), has been described in monophyodont (only one tooth generation) lizards on the lingual side of the developing functional tooth. This rudimentary lamina regresses, which has been proposed to play a role in preventing the formation of future generations of teeth. A similar rudimentary lingual structure has been reported associated with the first molar in the monophyodont mouse, and we show that this structure is common to all murine molars. Intriguingly, a lingual lamina is also observed on the non-replacing molars of other diphyodont mammals (pig and hedgehog), initially appearing very similar to the successional dental lamina on the replacing teeth. We have analyzed the morphological as well as ultrastructural changes that occur during the development and loss of this molar lamina in the mouse, from its initiation at late embryonic stages to its disappearance at postnatal stages. We show that loss appears to be driven by a reduction in cell proliferation, down-regulation of the progenitor marker Sox2, with only a small number of cells undergoing programmed cell death. The lingual lamina was associated with the dental stalk, a short epithelial connection between the tooth germ and the oral epithelium. The dental stalk remained in contact with the oral epithelium throughout tooth development up to eruption when connective tissue and numerous capillaries progressively invaded the dental stalk. The buccal side of the dental stalk underwent keratinisation and became part of the gingival epithelium, while most of the lingual cells underwent programmed cell death and the tissue directly above the erupting tooth was shed into the oral cavity. PMID:26010446

  12. Effective molarity in a nucleic acid-controlled reaction.

    PubMed

    Catalano, Michael J; Price, Nathan E; Gates, Kent S

    2016-06-01

    Positioning of reactive functional groups within a DNA duplex can enable chemical reactions that otherwise would not occur to an appreciable extent. However, few studies have quantitatively defined the extent to which the enforced proximity of reaction partners in duplex DNA can favor chemical processes. Here, we measured substantial effective molarities (as high as 25M) afforded by duplex DNA to a reaction involving interstrand cross-link formation between 2'-deoxyadenosine and a 2-deoxyribose abasic (Ap) site. PMID:27117430

  13. Fate of the Molar Dental Lamina in the Monophyodont Mouse

    PubMed Central

    Dosedělová, Hana; Dumková, Jana; Lesot, Hervé; Glocová, Kristýna; Kunová, Michaela; Tucker, Abigail S.; Veselá, Iva; Krejčí, Pavel; Tichý, František; Hampl, Aleš; Buchtová, Marcela

    2015-01-01

    The successional dental lamina (SDL) plays an essential role in the development of replacement teeth in diphyodont and polyphyodont animals. A morphologically similar structure, the rudimental successional dental lamina (RSDL), has been described in monophyodont (only one tooth generation) lizards on the lingual side of the developing functional tooth. This rudimentary lamina regresses, which has been proposed to play a role in preventing the formation of future generations of teeth. A similar rudimentary lingual structure has been reported associated with the first molar in the monophyodont mouse, and we show that this structure is common to all murine molars. Intriguingly, a lingual lamina is also observed on the non-replacing molars of other diphyodont mammals (pig and hedgehog), initially appearing very similar to the successional dental lamina on the replacing teeth. We have analyzed the morphological as well as ultrastructural changes that occur during the development and loss of this molar lamina in the mouse, from its initiation at late embryonic stages to its disappearance at postnatal stages. We show that loss appears to be driven by a reduction in cell proliferation, down-regulation of the progenitor marker Sox2, with only a small number of cells undergoing programmed cell death. The lingual lamina was associated with the dental stalk, a short epithelial connection between the tooth germ and the oral epithelium. The dental stalk remained in contact with the oral epithelium throughout tooth development up to eruption when connective tissue and numerous capillaries progressively invaded the dental stalk. The buccal side of the dental stalk underwent keratinisation and became part of the gingival epithelium, while most of the lingual cells underwent programmed cell death and the tissue directly above the erupting tooth was shed into the oral cavity. PMID:26010446

  14. Spontaneous emergence of overgrown molar teeth in a colony of Prairie voles (Microtus ochrogaster)

    PubMed Central

    Jheon, Andrew H; Prochazkova, Michaela; Sherman, Michael; Manoli, Devanand S; Shah, Nirao M; Carbone, Lawrence; Klein, Ophir

    2015-01-01

    Continuously growing incisors are common to all rodents, which include the Microtus genus of voles. However, unlike many rodents, voles also possess continuously growing molars. Here, we report spontaneous molar defects in a population of Prairie voles (Microtus ochrogaster). We identified bilateral protuberances on the ventral surface of the mandible in several voles in our colony. In some cases, the protuberances broke through the cortical bone. The mandibular molars became exposed and infected, and the maxillary molars entered the cranial vault. Visualisation upon soft tissue removal and microcomputed tomography (microCT) analyses confirmed that the protuberances were caused by the overgrowth of the apical ends of the molar teeth. We speculate that the unrestricted growth of the molars was due to the misregulation of the molar dental stem cell niche. Further study of this molar phenotype may yield additional insight into stem cell regulation and the evolution and development of continuously growing teeth. PMID:25634121

  15. Spontaneous emergence of overgrown molar teeth in a colony of Prairie voles (Microtus ochrogaster).

    PubMed

    Jheon, Andrew H; Prochazkova, Michaela; Sherman, Michael; Manoli, Devanand S; Shah, Nirao M; Carbone, Lawrence; Klein, Ophir

    2015-03-01

    Continuously growing incisors are common to all rodents, which include the Microtus genus of voles. However, unlike many rodents, voles also possess continuously growing molars. Here, we report spontaneous molar defects in a population of Prairie voles (Microtus ochrogaster). We identified bilateral protuberances on the ventral surface of the mandible in several voles in our colony. In some cases, the protuberances broke through the cortical bone. The mandibular molars became exposed and infected, and the maxillary molars entered the cranial vault. Visualisation upon soft tissue removal and microcomputed tomography (microCT) analyses confirmed that the protuberances were caused by the overgrowth of the apical ends of the molar teeth. We speculate that the unrestricted growth of the molars was due to the misregulation of the molar dental stem cell niche. Further study of this molar phenotype may yield additional insight into stem cell regulation and the evolution and development of continuously growing teeth. PMID:25634121

  16. Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans.

    PubMed

    Shen, Bing; Dong, Lin; Xiao, Shuhai; Lang, Xianguo; Huang, Kangjun; Peng, Yongbo; Zhou, Chuanming; Ke, Shan; Liu, Pengju

    2016-01-01

    Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (∼2,500-750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The convergence was driven by the abundant production of methyl sulphides (dimethyl sulphide and methanethiol) in euxinic or H2S-rich seawaters that were widespread in Proterozoic continental margins. In this convergence zone, methyl sulphides served as a non-competitive substrate supporting methane generation and methanethiol inhibited anaerobic oxidation of methane, resulting in the buildup of CH4, formation of degassing cracks in sediments and an increase in the benthic methane flux from sediments. Precipitation of crack-filling microspar was driven by methanogenesis-related alkalinity accumulation. Deep ocean ventilation and oxygenation around 750 Ma brought molar tooth structures to an end. PMID:26739600

  17. Variable permanent mandibular first molar: Review of literature

    PubMed Central

    Ballullaya, Srinidhi V; Vemuri, Sayesh; Kumar, Pabbati Ravi

    2013-01-01

    Introduction: The success of root canal therapy depends on the locations of all the canals, thourough debridement and proper sealing. At times the clinicians are challenged with variations in morphology of root canal. This review article attempts to list out all the variations of permanent mandibular first molar published so for in the literature. Materials and Methods: An exhaustive search was undertaken using PUBMED database to identify published literature from 1900 to 2010 relating to the root canal morphology of permanent first molar by using key words. The selected artcles were obtained and reviewed. Results: Total ninty seven articles were selected out of which 50 were original article and forty seven were case reports. The incidence of third canal in mesial root was 0.95% to 15%. The incidence of three rooted mandibular first molar was 3% to 33%. Only ninety cases reported with c-shape canal configuration. Incidence of Taurodintism without congenital disorder was very rare. Conclusion: The root canal treatment requires proper knowlegde of variations in root canal morphology in order to recognise, disinfect and seal all portal of exit. This can be accomplished with proper diagnosis using newer modes, modification in access preparation, use of operating microscope, enhanced methods of disinfecting and sealing of all canals. PMID:23716959

  18. The Use of Narrow Diameter Implants in the Molar Area

    PubMed Central

    Saad, M.; Assaf, A.; Gerges, E.

    2016-01-01

    Implant rehabilitations in the posterior jaw are influenced by many factors such as the condition of the remaining teeth, the force factors related to the patient, the quality of the bone, the maintenance of the hygiene, the limited bone height, the type and extent of edentulism, and the nature of the opposing arch. The gold standard is to place a regular diameter implant (>3.7 mm) or a wide one to replace every missing molar. Unfortunately, due to horizontal bone resorption, this option is not possible without lateral bone augmentation. In this situation, narrow diameter implant (NDI < 3.5 mm) could be the alternative to lateral bone augmentation procedures. This paper presents a clinical study where NDIs were used for the replacement of missing molars. They were followed up to 11 years. Special considerations were observed and many parameters were evaluated. NDI could be used to replace missing molar in case of moderate horizontal bone resorption if strict guidelines are respected. Yet, future controlled prospective clinical trials are required to admit their use as scientific evidence. PMID:27293436

  19. From molecular to molar: a paradigm shift in behavior analysis.

    PubMed Central

    Baum, William M

    2002-01-01

    A paradigm clash is occurring within behavior analysis. In the older paradigm, the molecular view, behavior consists of momentary or discrete responses that constitute instances of classes. Variation in response rate reflects variation in the strength or probability of the response class. The newer paradigm, the molar view, sees behavior as composed of activities that take up varying amounts of time. Whereas the molecular view takes response rate and choice to be "derived" measures and hence abstractions, the molar view takes response rate and choice to be concrete temporally extended behavioral allocations and regards momentary "responses" as abstractions. Research findings that point to variation in tempo, asymmetry in concurrent performance, and paradoxical resistance to change are readily interpretable when seen in the light of reinforcement and stimulus control of extended behavioral allocations or activities. Seen in the light of the ontological distinction between classes and individuals, extended behavioral allocations, like species in evolutionary taxonomy, constitute individuals, entities that change without changing their identity. Seeing allocations as individuals implies that less extended activities constitute parts of larger wholes rather than instances of classes. Both laboratory research and everyday behavior are explained plausibly in the light of concrete extended activities and their nesting. The molecular- view, because it requires discrete responses and contiguous events, relies on hypothetical stimuli and consequences to account for the same phenomena. One may prefer the molar view on grounds of elegance, integrative power, and plausibility. PMID:12144313

  20. The Use of Narrow Diameter Implants in the Molar Area.

    PubMed

    Saad, M; Assaf, A; Gerges, E

    2016-01-01

    Implant rehabilitations in the posterior jaw are influenced by many factors such as the condition of the remaining teeth, the force factors related to the patient, the quality of the bone, the maintenance of the hygiene, the limited bone height, the type and extent of edentulism, and the nature of the opposing arch. The gold standard is to place a regular diameter implant (>3.7 mm) or a wide one to replace every missing molar. Unfortunately, due to horizontal bone resorption, this option is not possible without lateral bone augmentation. In this situation, narrow diameter implant (NDI < 3.5 mm) could be the alternative to lateral bone augmentation procedures. This paper presents a clinical study where NDIs were used for the replacement of missing molars. They were followed up to 11 years. Special considerations were observed and many parameters were evaluated. NDI could be used to replace missing molar in case of moderate horizontal bone resorption if strict guidelines are respected. Yet, future controlled prospective clinical trials are required to admit their use as scientific evidence. PMID:27293436

  1. Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans

    NASA Astrophysics Data System (ADS)

    Shen, Bing; Dong, Lin; Xiao, Shuhai; Lang, Xianguo; Huang, Kangjun; Peng, Yongbo; Zhou, Chuanming; Ke, Shan; Liu, Pengju

    2016-01-01

    Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (~2,500-750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The convergence was driven by the abundant production of methyl sulphides (dimethyl sulphide and methanethiol) in euxinic or H2S-rich seawaters that were widespread in Proterozoic continental margins. In this convergence zone, methyl sulphides served as a non-competitive substrate supporting methane generation and methanethiol inhibited anaerobic oxidation of methane, resulting in the buildup of CH4, formation of degassing cracks in sediments and an increase in the benthic methane flux from sediments. Precipitation of crack-filling microspar was driven by methanogenesis-related alkalinity accumulation. Deep ocean ventilation and oxygenation around 750 Ma brought molar tooth structures to an end.

  2. Determination of partial molar volumes from free energy perturbation theory†

    PubMed Central

    Vilseck, Jonah Z.; Tirado-Rives, Julian

    2016-01-01

    Partial molar volume is an important thermodynamic property that gives insights into molecular size and intermolecular interactions in solution. Theoretical frameworks for determining the partial molar volume (V°) of a solvated molecule generally apply Scaled Particle Theory or Kirkwood–Buff theory. With the current abilities to perform long molecular dynamics and Monte Carlo simulations, more direct methods are gaining popularity, such as computing V° directly as the difference in computed volume from two simulations, one with a solute present and another without. Thermodynamically, V° can also be determined as the pressure derivative of the free energy of solvation in the limit of infinite dilution. Both approaches are considered herein with the use of free energy perturbation (FEP) calculations to compute the necessary free energies of solvation at elevated pressures. Absolute and relative partial molar volumes are computed for benzene and benzene derivatives using the OPLS-AA force field. The mean unsigned error for all molecules is 2.8 cm3 mol−1. The present methodology should find use in many contexts such as the development and testing of force fields for use in computer simulations of organic and biomolecular systems, as a complement to related experimental studies, and to develop a deeper understanding of solute–solvent interactions. PMID:25589343

  3. Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans

    PubMed Central

    Shen, Bing; Dong, Lin; Xiao, Shuhai; Lang, Xianguo; Huang, Kangjun; Peng, Yongbo; Zhou, Chuanming; Ke, Shan; Liu, Pengju

    2016-01-01

    Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (∼2,500–750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The convergence was driven by the abundant production of methyl sulphides (dimethyl sulphide and methanethiol) in euxinic or H2S-rich seawaters that were widespread in Proterozoic continental margins. In this convergence zone, methyl sulphides served as a non-competitive substrate supporting methane generation and methanethiol inhibited anaerobic oxidation of methane, resulting in the buildup of CH4, formation of degassing cracks in sediments and an increase in the benthic methane flux from sediments. Precipitation of crack-filling microspar was driven by methanogenesis-related alkalinity accumulation. Deep ocean ventilation and oxygenation around 750 Ma brought molar tooth structures to an end. PMID:26739600

  4. Determination of partial molar volumes from free energy perturbation theory.

    PubMed

    Vilseck, Jonah Z; Tirado-Rives, Julian; Jorgensen, William L

    2015-04-01

    Partial molar volume is an important thermodynamic property that gives insights into molecular size and intermolecular interactions in solution. Theoretical frameworks for determining the partial molar volume (V°) of a solvated molecule generally apply Scaled Particle Theory or Kirkwood-Buff theory. With the current abilities to perform long molecular dynamics and Monte Carlo simulations, more direct methods are gaining popularity, such as computing V° directly as the difference in computed volume from two simulations, one with a solute present and another without. Thermodynamically, V° can also be determined as the pressure derivative of the free energy of solvation in the limit of infinite dilution. Both approaches are considered herein with the use of free energy perturbation (FEP) calculations to compute the necessary free energies of solvation at elevated pressures. Absolute and relative partial molar volumes are computed for benzene and benzene derivatives using the OPLS-AA force field. The mean unsigned error for all molecules is 2.8 cm(3) mol(-1). The present methodology should find use in many contexts such as the development and testing of force fields for use in computer simulations of organic and biomolecular systems, as a complement to related experimental studies, and to develop a deeper understanding of solute-solvent interactions. PMID:25589343

  5. Molar Macrowear Reveals Neanderthal Eco-Geographic Dietary Variation

    PubMed Central

    Fiorenza, Luca; Benazzi, Stefano; Tausch, Jeremy; Kullmer, Ottmar; Bromage, Timothy G.; Schrenk, Friedemann

    2011-01-01

    Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources. PMID:21445243

  6. Efficacy of Postoperative Prophylactic Antibiotic Therapy in Third Molar Surgery

    PubMed Central

    Reddy B, Praveen

    2014-01-01

    Introduction: Surgical extraction of mandibular third molar is the most frequently performed procedure in oral surgery. This procedure is associated with significant postoperative sequelae such as trismus, swelling, pain and infection. The need of antibiotic therapy during the removal of mandibular third molar has been a contentious issue. Method: This study investigated a regimen by using amoxycillin and metronidazole in one group and without using antibiotics in the other. Both the groups were assessed postoperatively on the 1st, 2nd, 5th, 7th and 10th days by the same observer for post operative mouth opening (interincisal distance), presence of a purulent discharge at the site of surgery, pain and swelling. Result: Overall, no statistically significant difference was seen between both the treatment groups when interincisal distance, pain, swelling and purulent discharge were considered. Conclusion: The results of this study failed to show any advantage which was associated with the routine postoperative use of antibiotics in asymptomatic third molar surgeries. PMID:24995236

  7. [Anatomical visibility of the meridian information channels].

    PubMed

    Chang, Xi-lang

    2008-12-01

    The "structure imperfectness of signal channel rule" put forward by the author of the present paper may provide a theoretical evidence for the systematicness of meridian information channel. The conclusion that no special structure of the meridian-collateral system has been found is likely to serve as a piece of counterevidence. According to the latest structural view, the development of capillaries, lymphatic vessels and nerves needs target cells-released inducible factors. In the initial phase of the development of the organism, the asymmetry of the interspaces among cells results in the production and arrangement imbalance of the sequential factors which make the capillaries, lymphatic vessels and nerves distribute sequentially in time and space. Meridian-collateral, following the "systemic statistic distribution rule", is a general expression of this distribution pattern. As a systematic structure, the meridian-collateral system distributes in an optimized way in the human body and has both orderly and compatible characteristics. The author thinks that the meridian-collateral information channel is anatomically visible in the time and spatial structure, and in its logical structure and compatibility during the process of growth. Hence, many techniques of delicate anatomy, quantitative anatomy, growth anatomy, comparative anatomy, tridimensional remodeling of living creature and dynamical remodeling of growth all should be used as the important tools for studying the meridian information channel. The theory and the anatomical techniques determine what you would finally find. PMID:19288907

  8. Anatomical and molecular imaging of skin cancer

    PubMed Central

    Hong, Hao; Sun, Jiangtao; Cai, Weibo

    2008-01-01

    Skin cancer is the most common form of cancer types. It is generally divided into two categories: melanoma (∼ 5%) and nonmelanoma (∼ 95%), which can be further categorized into basal cell carcinoma, squamous cell carcinoma, and some rare skin cancer types. Biopsy is still the gold standard for skin cancer evaluation in the clinic. Various anatomical imaging techniques have been used to evaluate different types of skin cancer lesions, including laser scanning confocal microscopy, optical coherence tomography, high-frequency ultrasound, terahertz pulsed imaging, magnetic resonance imaging, and some other recently developed techniques such as photoacoustic microscopy. However, anatomical imaging alone may not be sufficient in guiding skin cancer diagnosis and therapy. Over the last decade, various molecular imaging techniques (in particular single photon emission computed tomography and positron emission tomography) have been investigated for skin cancer imaging. The pathways or molecular targets that have been studied include glucose metabolism, integrin αvβ3, melanocortin-1 receptor, high molecular weight melanoma-associated antigen, and several other molecular markers. Preclinical molecular imaging is thriving all over the world, while clinical molecular imaging has not lived up to the expectations because of slow bench-to-bedside translation. It is likely that this situation will change in the near future and molecular imaging will truly play an important role in personalized medicine of melanoma patients. PMID:21437135

  9. Anatomical modeling of the bronchial tree

    NASA Astrophysics Data System (ADS)

    Hentschel, Gerrit; Klinder, Tobias; Blaffert, Thomas; Bülow, Thomas; Wiemker, Rafael; Lorenz, Cristian

    2010-02-01

    The bronchial tree is of direct clinical importance in the context of respective diseases, such as chronic obstructive pulmonary disease (COPD). It furthermore constitutes a reference structure for object localization in the lungs and it finally provides access to lung tissue in, e.g., bronchoscope based procedures for diagnosis and therapy. This paper presents a comprehensive anatomical model for the bronchial tree, including statistics of position, relative and absolute orientation, length, and radius of 34 bronchial segments, going beyond previously published results. The model has been built from 16 manually annotated CT scans, covering several branching variants. The model is represented as a centerline/tree structure but can also be converted in a surface representation. Possible model applications are either to anatomically label extracted bronchial trees or to improve the tree extraction itself by identifying missing segments or sub-trees, e.g., if located beyond a bronchial stenosis. Bronchial tree labeling is achieved using a naïve Bayesian classifier based on the segment properties contained in the model in combination with tree matching. The tree matching step makes use of branching variations covered by the model. An evaluation of the model has been performed in a leaveone- out manner. In total, 87% of the branches resulting from preceding airway tree segmentation could be correctly labeled. The individualized model enables the detection of missing branches, allowing a targeted search, e.g., a local rerun of the tree-segmentation segmentation.

  10. Arthroscopic Anatomic Glenoid Reconstruction Without Subscapularis Split

    PubMed Central

    Wong, Ivan H.; Urquhart, Nathan

    2015-01-01

    The role of bone loss from the anterior glenoid in recurrent shoulder instability has been well established. We present a completely arthroscopic technique for reconstructing the anterior glenoid with distal tibial allograft and without a subscapularis split. We perform the arthroscopy in the lateral position. We measure and size an allograft distal tibial graft and place it arthroscopically. We use an inside-out medial portal to introduce the graft into the shoulder, passing it through the rotator interval and above the subscapularis. A double-cannula system is used to pass the graft, which is temporarily fixed with K-wires and held in place with cannulated screws. We then perform a Bankart-like repair of the soft tissues to balance the shoulder and augment our repair. Our technique is not only anatomic in the re-creation of the glenoid surface but also anatomic in the preservation of the coracoid and subscapularis tendon and repair of the capsulolabral complex. PMID:26697303