Comparison of Second Molar Eruption Pattern in Skeletal Class I and Class III Malocclusions Among 8 9 Years Old Children
Roshanak Ghaffari1, Arman Salehi2 and Negar Salehi3*1Department of Oral and Maxillofacial Radiology, Dental School, Khorasgan (Isfahan) Branch, Islamic Azad University, Isfahan, Iran. 2Department of Operative Dentistry, Dental School, Rafsanjan University of Medical Sciences, Rafsanjan, Iran. 3Department of Oral Medicine and Orofacial pain, Dental School, Kerman University of Medical Sciences, Kerman, Iran.
Abstract: Timing and the position of second molar eruption are important factors in orthodontic therapy, which might be related to craniofacial morphology and malocclusion. This cross-sectional study was aimed to comparatively investigate the second molar position in skeletal Class I and Class III malocclusions. Pretreatment history of 60 orthodontic patients, 34 girls and 26 boys with an age range of 8 9 years, were studied. Approximately, 55% had skeletal Class I malocclusion, 23.3% had skeletal Class III malocclusion with maxillary retrognathism and 21.7% had skeletal Class III malocclusion with mandibular prognathism. Position of second molar eruption relative to the reference line and the second molar developmental stage, as well as the dental age, were determined using panoramic radiographs. Data was analyzed using chi-squared test and ANOVA. The relationship between malocclusion and Nolla developmental stage was significant (P<0.0001). The distance between the second molar and the reference line in Class III patients in comparison to Class I patients was significantly more occlusal. Position of maxillary and mandibular second molar eruption in Class I malocclusion in comparison to Class III malocclusion was more retrusive and more apical, which was significant on the left side. In patients with Class III mandible, the second molar had a more occlusal position on both the left and right sides.
Keywords: Class I; Class III; Eruption; Molar; Malocclusion Back to TOC