Assessment of bone density in edentulous maxillae using cone beam computed tomography (CBCT).

INTRODUCTION: In edentulous maxillae, the anterior maxilla is the region of interest for implant placement due to posterior bone resorption and sinus pneumatization. This study aimed to assess variations in bone density in different regions of the edentulous maxilla according to sex and age, using cone beam computed tomography (CBCT). MATERIALS AND METHODS: 69 CBCT from edentulous maxilla were analyzed. Six virtual implants were planned between the maxillary sinuses at incisor, canine, and premolar sites. Bone densities (in Hounsfield units HU) were recorded at six points on the neck, body, and apex of the buccal and lingual areas of each virtual implant. We used the two-sample t-test to compare male and female bone densities, and the Spearman correlation coefficient to analyze the correlation between mean bone density and age. One-way analysis of variance with post hoc pairwise t-tests was used to analyze the differences in density between three sites of the edentulous maxilla and the differences in density between three parts of the implant. The significance level was set at 5%. RESULTS: Mean bone density in males was significantly higher than in females. There was a significant correlation between mean bone density and age in females. Incisor sites showed the highest mean bone density, followed by canine and premolar sites. There was a significant decline in bone density from the neck to the apex. CONCLUSIONS: Bone density varied within and among edentulous maxillae. Bone density of the edentulous maxilla seemed to be influenced by age in women and by sex.

Lingual foramina of the anterior mandible in edentulous patients: CBCT analysis and surgical risk assessment.

OBJECTIVE: The mandible has various unnamed accessory foramina, and surgery is often performed in the symphyseal area. The aim of this study was to analyze the anatomical characteristics of mandibular lingual foramina with the objective of preventing clinical complications during implant surgery on an edentulous mandible. STUDY DESIGN: A total of 100 cone beam computed tomography scans of completely edentulous patients were included in this study. For each canal, nine measurements were recorded in millimeters: seven length or height measurements and two diameter measurements. The placement of a standard implant was simulated and whether the implant passed through the canal was noted. The results were analyzed by t-test and chi-squared at a significance level of 0.05. Pearson correlation analysis was used to assess the relationship between variables. RESULTS: We identified 309 foramina: 236 medial lingual foramina and 73 lateral lingual foramina. We found no significant relationship between the number of foramina and the age of the individuals, or between diameter and the age or gender of the individuals. The mandibular canal was injured in 32.7 % of implant placement simulations. CONCLUSION: The risk of injury to neurovascular bundles is increased in edentulous patients due to vertical bone resorption.