Description:
Objective: The objective of this study was to retrospectively investigate the facial alveolar bone (FAB) thickness and fenestration rate of maxillary first and second premolars using cone-beam computed tomography (CBCT). Design: A total of CBCT images of 66 patients were selected and 200 maxillary premolar (100 first and 100 second premolar) were included. The FAB thicknesses were measured at 1,3 and 5 mm apical to the alveolar bone peak. The prevalence of fenestration in maxillary premolars was recorded. The statistical analyses were performed. Results: The FAB thicknesses of the second premolars (1.39 mm at 1 mm, 1.42 mm at 3 mm, and 1.22 mm at 5 mm) were significantly higher than the first premolars (1.11 mm at 1 mm, 0.70 mm at 3 mm, and 0.48 mm at 5 mm) at 1, 3, and 5 mm levels (p < 0.05). The lowest prevalence (1 %) of the thickness of FAB ≥ 2 mm was in the first premolar has at 5 mm apical of the alveolar bone peak. The overall prevalence of fenestration in maxillary premolars was found as 30.5 %. There was a statistically significant difference between first and second premolars (p < 0.05). Conclusion: The FAB thicknesses are lower in the first premolar than the second premolar. The lowest FAB thickness was in the first premolar at 5 mm apical of the bone crest as 0.42 mm. The prevalence of fenestration in maxillary premolars was higher in the Turkish subpopulation than in other populations. Fenestration was more common in the maxillary first premolar.