Bone dimensions relationship with gingival phenotype in smokers and nonsmokers using cone-beam computed tomography.

Background: This study aimed to assess the relationship of maxillary alveolar bone thickness (BT) and height (BH) with gingival phenotype (GP) in smokers and nonsmokers using cone-beam computed tomography (CBCT).

Methods: This cross-sectional study was conducted on 60 participants. The participants underwent periodontal examination, and their GP was determined by placing a periodontal probe in the gingival sulcus at the midline and observing the transparency. The participants were then assigned to four groups (n = 15) based on their smoking status and GP: thin phenotype/smoker, thick phenotype/smoker, thin phenotype/nonsmoker, and thick phenotype/nonsmoker. BT and BH of the participants were measured in the sagittal plane on CBCT scans at the bone crest and at 2, 4, and 6 mm apical to the crest at the site of maxillary central and lateral incisors. Data were analyzed by two-way ANOVA and LSD test (alpha = 0.05).

Results: The distance between the cementoenamel junction (CEJ) of maxillary central and lateral incisors and alveolar bone crest in smokers was significantly greater than that in nonsmokers (p < 0.001). Smoking had no significant effect on alveolar BT at the crestal level or 2, 4, and 6 mm apical to the crest. BT at the crest and 2, 4, and 6 mm apical to the crest was significantly greater in thick, versus thin, GP (p < 0.001).

Conclusion: Smoking significantly increased the distance between the CEJ and alveolar crest at the site of central and lateral incisors but had no significant effect on BT.

Plain language summary: This study found that smoking significantly increased the distance between the cementoenamel junction and the alveolar bone crest in maxillary incisors but did not affect alveolar bone thickness, which was greater in individuals with a thick gingival phenotype compared to those with a thin gingival phenotype.