Abstract
ABSTRACT Objective: The aims of this study were to evaluate the angle of permanent second molars in schoolchildren with a normal occlusion, using panoramic radiographs and plaster models, and to evaluate the correlation between measurements obtained by these two methods. Methods: Thirty Brazilian schoolchildren with a mean age of 14 years and 7 months were selected. These individuals had not previously undergone orthodontic interventions, required a minimum of four of Andrews' six keys of occlusion, with the first key (interarch relation) being mandatory, and significant facial asymmetry was absent. Angulation of the maxillary second molars was measured using panoramic radiographs and plaster models. Results: The mean angulation, according to panoramic radiography, was 105.8º in the distal direction (standard deviation of 5.1º). The plaster models revealed a mean angulation of -5.8º, indicating a distal angulation of the crown. Pearsons' correlation test demonstrated a negative and weak relationship (p = 0.009; r2 = - 0.474), with a greater angle in the panoramic radiographs and a smaller angle in plaster models. This was considered an inverse proportional relationship. Conclusion: Measurements of the panoramic radiographs showed an angulation of 105.8º in the distal direction, while the plaster models revealed an angulation of -5.8º. Therefore, one should consider these angulations in order to personalize the placement of accessories on the upper permanent second molars. Correlation of this angulation using these two methods was negative; however, due to the weak correlation, both methods are needed when evaluating the angle of the upper second molar.
Highlights
The upper second molars are the last permanent teeth of the upper arch to erupt, following a posterior eruption route at a negative angle that may progressively become less negative, possibly positive, as the occlusion matures
Measurements of the panoramic radiographs showed an angulation of 105.8o in the distal direction, while the plaster models revealed an angulation of -5.8o
One should consider these angulations in order to personalize the placement of accessories on the upper permanent second molars
Summary
The upper second molars are the last permanent teeth of the upper arch to erupt, following a posterior eruption route at a negative angle that may progressively become less negative, possibly positive, as the occlusion matures. In the vast majority of cases, the second molars receive little attention on the part of the orthodontist[3,4], which can be verified by the lack of studies on this theme in the literature, in terms of angulation. It was Andrews[5] who evaluated more than 100 individuals with a natural and seemingly perfect occlusion, with regards to angle, inclination, prominence, width and length of each tooth crown. In order to develop a prescription that can position the teeth closer to the normal natural, studies are needed on the position and angle that are deemed normal[3,4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
