Ectopic Eruption of the First Permanent Molar in the Maxilla: Cephalometric Features of 13 Pediatric Patients

Ectopic eruption of the first permanent molar in the maxilla, generally characterized by the wrong axial positioning during eruption, is reported to occur in about 2–6% of children. Its incidence is surely under-estimated as it frequently remains undiagnosed and, additionally, becomes irreversible, resulting in posterior crowding in such cases. This retrospective study aims to investigate the cephalometric features of patients affected by ectopic eruption of the maxillary first molar in comparison to a control group of patients. From a total of 1935 subjects, 13 patients were enrolled in the study group, while 26 patients were randomly selected as a control group. Lateral cephalometric teleradiographs obtained at the time of diagnosis were used to measure cephalometric values between study patients and controls. The prevalence of ectopic eruption of the first maxillary permanent molar in our patients was 1.14%. The mandibular angle (SN-GoMe) was found to be significantly greater in the study group than in control. The same statistical trend was observed for the inter-maxillary angle (SnaSnp-GoMe); also, the distance Sna-Me was greater in the study group. Differences between groups were statistically significant for the following distances: Snp-Sna, Ba-S and SOR-Sna, which were found to be, overall, greater in the study group. Ectopic eruption of the first permanent molar in the maxilla seems to be associated with morphogenetic characteristics of patients, mainly with a dolichocephalic pattern.