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Anatomy and Embryology of the Mouth and Dentition
Published in John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford, Head & Neck Surgery Plastic Surgery, 2018
Posterior to the premolars are three molars whose size decreases as one passes backwards. Each has a large rhomboid (upper jaw) or rectangular (lower jaw) occlusal surface with four or five cusps. The maxillary first molar has a cusp at each corner of its occlusal surface and the mesiopalatal cusp is connected to the distobuccal by an oblique ridge. A smaller cusplet or tubercle (cusplet of Carabelli) usually appears on the mesiopalatal cusp. The tooth has three widely separated roots, two buccal and one palatal. The smaller maxillary second molar has a reduced distopalatal cusp. Its three roots are less divergent and two of them may be fused. The maxillary third molar, the smallest, is very variable in form. It usually has three cusps (the distopalatal being absent) and commonly the three roots are fused.
Dental Trauma
Published in Jeffrey R. Marcus, Detlev Erdmann, Eduardo D. Rodriguez, Essentials of CRANIOMAXILLOFACIAL TRAUMA, 2014
Mark Daniel Fisher, Martha Ann Keels, Tom McGraw, Cynthia Neal, Kenneth Pinkerton
The pediatric or primary dentition includes 20 teeth denoted by letters A through T, totaling 20 teeth. Lettering begins from the right maxillary second molar. After reaching the left maxillary second molar (tooth J), lettering proceeds from the left second mandibular molar (K-T). Primary teeth include 4 incisors, 2 canines, and 4 molars per arch. There are no premolars.
Radiographic Applications in Forensic Dental Identification
Published in Michael J. Thali M.D., Mark D. Viner, B. G. Brogdon, Brogdon's Forensic Radiology, 2010
Sample case 2 (Figure 10.21). The second comparison resulted from a motor vehicle accident involving an automo-bile and a speeding dump truck carrying hot asphalt colliding head-on. The victim sustained blunt force trauma and severe thermal damage. Only the segment of bone that represented the maxillary right posterior segment survived the event. However, when the postmortem image was compared with the antemortem image of the suspected victim, a wealth of concordant dental restorative findings were apparent. The maxillary bicuspids in both images had been restored with a PFM crown and an MOD amalgam with a space between the two. The maxillary first molar had been restored with an amalgam in a manner that encircled the crown. However, the most unique finding was the crown on the maxillary second molar. This PFM crown very poorly fit the margins of the tooth structure with excess metal extending into the embrasure. This crown would normally have been replaced by any prudent practitioner as such an ill fitting crown will surely lead to a food trap resulting in periodontal disease and dental caries of the root surfaces. This was determined to be a positive dental identification.
Morphological variations and prevalence of aberrant traits of primary molars
Published in Annals of Human Biology, 2021
P. Sujitha, R. Bhavyaa, M. S Muthu, M. Kirthiga
The parastyle is a paramolar cusp of Bolk that occurs on the mesiobuccal surface of upper molars (Turner et al. 1991). Although the literature pertaining to this trait is negligible, it is said to be predominant in deciduous molars (Kustaloglu 1962). In the present study, the results yielded a prevalence rate of 0.51% in primary maxillary second molars and 3.48% in primary maxillary first molars. Studies conducted among southwestern and northwestern Indians (Kustaloglu 1962) gave a prevalence of 5.2% and 4.7%, respectively, in primary maxillary second molars. The prevalence found in the present study was comparatively less in primary maxillary second molars. However, the prevalence of the parastyle was higher in primary maxillary first molars. The literature suggests primary maxillary first molars to be the “premolar section” of the primary dentition and to resemble certain features of premolars (Nelson and Ash 2012). The literature also suggests that this trait occurs more in premolars (Kustaloglu 1962), which can be the reason for its higher prevalence in primary maxillary first molars.