Mesiodistal root angulation of permanent teeth in children with mixed dentition and normal occlusion

Abstract

ObjectiveThere is little information regarding the mesiodistal angulation of permanent teeth in mixed dentition. The aim of this study was to evaluate mesiodistal root angulation of permanent incisors, canines and first molars of 100 Brazilian children, using a new horizontal reference plane based on the midpoint of the intercuspation of primary canines and permanent first molars in panoramic radiographs during the mixed-dentition phase. Material and methodsChildren were equally divided between the genders with a mean age of 8.9 years (SD=0.76), normal occlusion and no eruptive disturbances. ResultsThe angulation of the permanent maxillary first molars was close to the vertical, whereas the mandibular molars presented approximately 25 degrees of distal root angulation. The maxillary canines were the most distally angulated teeth, whereas the permanent mandibular canines were vertically positioned. The evaluation of the anterior maxillary area showed vertical position of permanent lateral, and central incisors with a slight distal angulation, whereas the permanent mandibular incisors tended to a mesial radicular convergence. ConclusionsThe proposed reference line could be useful in mixed dentition root angulation evaluation; there was a slight asymmetry in the mesiodistal angulation among homologous teeth, and also a small variation between the male and the female groups, but no difference between 8-and 10-year-old children.

Influence of treatment including second molars on final and postretention molar angulation

“…In addition, it is the best option to evaluate teeth axial inclinations and root parallelism after orthodontic treatment. 2,[5][6][7]11,12,13,15,17,24 As occurring in other radiographic methods, the dimensions of structures in panoramic radiographs can be magnified 5,7,8,11,12,13,[15][16][17][18][19] and due to distortions, horithe three evaluated stages. On the other hand, results for the intragroup comparison in Group 2 (#37 and #47 teeth included) demonstrated significant uprighting of mandibular first and second molars throughout treatment, which remained stable during the postretention stage (Table 2).…”

“…A lateral cant of the occlusal plane less than 10 degrees without an upward anterior rotation showed no significant effect on the measurements. Regarding angular measurements, the literature reports that the analysis of dental angulations through panoramic radiographs can be performed with good reliability 8,11,12,13,15,17,18,19 and that there is some tolerance of variation in head position. 18 During the radiographic examination, all patients who comprised the sample were positioned with both the occlusal plane parallel and the sagittal plane perpendicular to the ground.…”

“…Adequate mesiodistal teeth angulations with roots parallel to each other are frequently mentioned in the literature 1,3,8,[9][10][11][12][13] as a fact that not only improves teeth alignment stability in their apical bases, but also allows normal maxilomandibular occlusion. 6 Moreover, an adequate mesiodistal positioning allows a uniform distribution of occlusal forces through contact points and contributes to overall treatment stability.…”

Evaluation of Mesiodistal Inclination of Permanent Maxillary and Mandibular First Molar in Different Angle’s Molar Relation - A Cephalometric Study

“…[2] Mesiodistal root angulation alterations of the maxillary and mandibular incisors may significantly change the molar relationship. [3] In Angle's Class I molar relation, mesiobuccal cusp of upper first permanent molar lies in the buccal groove of lower first permanent molar. Whereas in Class II molar relation, the mesiobuccal groove of upper first molar lies in the interdental area between the second PM and first molar.…”

“…Flavia et al conducted a study to evaluate the mesiodistal root inclination of permanent incisors, canines, and first molar of Brazilian children with mixed dentition, using the horizontal reference line drawn on a panoramic radiograph. [3] Several tools have been used for assessing the inclination of teeth: Cephalometric angular measurements, conveyor and compass on dental casts, etc. [4] All teeth are arranged at an angle to the occlusal plane and each has an optimum inclination mesiodistally to best perform its individual and collective functions.…”