Cone-Beam CT Assessment of the Position of the Medial Lingual Foramen for Dental Implant Placement in the Anterior Symphysis.

OBJECTIVES: To determine the position of the mandibular medial lingual foramen with cone-beam CT (CBCT) 3D imaging modalities when implants are to be placed in the anterior symphysis of the mandible. MATERIALS AND METHODS: A total of 111 CBCTs were considered acceptable and analyzed. The variables measured were as follows: (1) length of the outlet duct; (2) distance from the canal to the buccal cortex; (3) distance from the canal to the inferior cortex; (4) distance from the canal to the lingual cortex; (5) distance from the canal to the alveoli of the nearest tooth in dentate patients and distance from the canal to the marginal crest in edentulous patients; (6) angle of the duct to the horizontal Frankfurt plane; (7) diameter of the exit orifice; and (8) output level of the socket in relation to the teeth and the presence of bifurcations. RESULTS: A single canal was observed in 64% of patients; 2 canals were observed in 33% of patients; and a triple foramen was observed in 3% of patients. Women showed slightly lower values than men for each of the analyzed variables, with statistically significant differences in the length of the canal in edentulous (P = 0.029) and dentate patients (P = 0.027). CONCLUSION: The medial lingual foramen should be considered while performing presurgical planning. Careful attention is needed while setting the placement position of the dental implant to decrease the risk of complications.

Characterization of the Maxillary Sinus Using Cone Beam Computed Tomography. A Retrospective Radiographic Study.

PURPOSE: To analyze the anatomical findings and alterations of the maxillary sinus in asymptomatic patients observed by cone beam computed tomography. MATERIALS AND METHODS: A cross-sectional retrospective study of the anatomical variations and alterations of the maxillary sinus was made in 160 patients-71 males (44.3%) and 89 females (55.6%), with an age range of 18 to 74 years-measuring the thickness of the Schneiderian membrane and the cortical thickness of the lower margin of the maxillary sinus (in its most caudal portion), and correlations among the different study variables were assessed. RESULTS: Sinus pneumatization was the most frequent anatomical finding (81.3%). A negative correlation was observed between the thickness of the Schneiderian membrane and the presence of Underwood septa (P < 0.005). Mucosal thickening of more than 2 mm was directly correlated with the presence of maxillary sinus lesions (opacification, discontinuity of the floor of the sinus, polypoid lesions, or air-liquid levels). CONCLUSION: The presence or absence of septa seems to be related to the thickness of the Schneiderian membrane.