Difference in Buccal Gingival Thickness between the Mandible and Maxilla in the Aesthetic Zone: A Systematic Review and Meta-Analysis

Gingival phenotype prevalence of lower incisors and associated risk indicators in the French dental student population: a cross-sectional study

OBJECTIVES

To investigate the prevalence of the gingival phenotype in the mandibular incisor area and the associated risk indicators.

MATERIALS AND METHODS

This cross-sectional study involved clinical examination to record main periodontal characteristics (gingival phenotypes) at the tooth level. Then, a phenotype at the subject level was defined as fragile (at least one thin phenotype on one of the four incisors) versus resistant (no thin phenotype on the four incisors). Furthermore, orthodontic parameters were assessed based on photographic examination. Two blinded periodontists and two blinded orthodontists were involved in the data collection. Univariate and multivariate logistic regression models were implemented.

RESULTS

A total of 119 students were included, encompassing 476 incisors. The prevalence of gingival phenotypes at the tooth level was as follows: thin/high (63.9%), thick/high (36.3%), thin/reduced (5.9%), and thick/reduced (0.2%). At the subject level, the fragile phenotype predominated (81.5%) and showed a significant correlation with the visibility of roots prominence (OR = 4.09, 95% CI: 1.47-11.41, p = 0.007).

CONCLUSIONS

Considering the conditions of this study, in the mandibular incisor area, the thin/high gingival phenotype exhibited the highest prevalence at the tooth level. At the subject level, the presence of visible roots prominence was identified as the only significant risk indicator associated with the fragile phenotype.

CLINICAL RELEVANCE

General practitioners, periodontists and orthodontists should consider the mandibular incisor sector as a vulnerable area. Categorizing the overall gingival phénotype into 4 types improves the diagnostic approach and allows better identification of high-risk phenotypes, especially in cases requiring multidisciplinary management.

CLINICALTRIAL

GOV RECORD

Number NCT05813444.

Comparison of gingival thickness by CBCT versus transgingival probing and estimation of cut-off values for gingival phenotype - A cross-sectional study in adults

AIM

Gingival phenotype (GP) is regarded as a valuable indicator for forecasting the probability of attaining favourable aesthetic and functional results with orthodontic treatment. This study aimed to investigate the accuracy and reproducibility of cone beam computed tomography (CBCT) for assessing gingival thickness (GT) in both arches compared to the transgingival probing method. The secondary objective was to determine the optimal cut-off values for GT using CBCT.

METHODS

This cross-sectional study was conducted where GP was determined based on the probe transparency method (TRAN). The GT measurements were obtained by both methods at 2mm from the free gingival margin (FGM) for all teeth anterior to the first molar. The data was statistically analysed using intraclass correlation coefficient (ICC), Bland-Altman plots, and receiver operating characteristic (ROC) curves. The statistical significance level was set at a P-value<0.05.

RESULTS

The study included 60 subjects (1200 teeth). The mean GT in both the maxillary (1.14±0.17mm) and mandibular (0.94±0.15mm) arches was significantly greater (P<0.05) for the transgingival probing method than for the CBCT method. As shown in the Bland-Altman plot, the bias between the two methods was greater in the maxillary jaw (0.060; 95% CI: 0.044 to 0.076) and in individuals with a thick GP (0.096; 95% CI: 0.082 to 0.109). The optimal values for GT measurements were 1.15mm for the maxillary jaw, 1.02mm for the mandibular jaw, 1.02mm for males, and 1.09mm for females.

CONCLUSIONS

CBCT exhibited notable precision in diagnosing GT, while demonstrating minimal disparities compared to the conventional transgingival probing technique, particularly evident in thin GPs, and in the mandibular dental arch. The constraints associated with the utilization of CBCT were observed in the maxillary arch and in cases with thick GP.