OBJECTIVE: To evaluate cephalometric changes in patients after bilateral loss of lower first permanent molar teeth. METHODS: Sixty-eight lateral radiographs of patients from private practices were analyzed. The sample was divided into two groups matched for age and gender: 34 individuals without loss (control group) and 34 presenting with bilateral loss of lower first permanent molar teeth (loss group). Patients who had lost teeth other than first molars, cases of agenesis and patients under 16 years of age were excluded from the sample. Only individuals who reported losing teeth at least 5 years earlier were evaluated. RESULTS: It was found that bilateral loss of lower first permanent molars leads to smooth closure of GnSN angle (P=0.05), counterclockwise rotation of occlusal plane (P=0.0001), mild decrease in lower anterior face height (P=0.05), pronounced lingual tipping (P=0.04) and retrusion of mandibular incisors (P=0.03). Moreover, bilateral loss of lower first permanent molars did not affect the maxillomandibular relationship in the anteroposterior direction (P=0.21), amount of treatment (P=0.45), inclination of upper incisors (P=0.12) and anteroposterior position of maxillary incisors (P=0.46). CONCLUSION: Bilateral loss of lower first molars can produce marked changes in lower incisor positioning and in the occlusal plane as well as a mild reduction of the face in the vertical direction
First permanent molar; Cephalometry
