The effect of Sequential Retraction of Maxillary Incisors on Anterior Gingival Biotypes

To evaluate the effect of sequential retraction of maxillary incisors on the gingival biotypes.

This cross-sectional was conducted in the Department of Orthodontics at Altamash Institute of Dental Medicine, Karachi. Duration of study was one year from June 2023 to July 2024. A total of 50 patients aged 18-30 years, diagnosed with Angle Class II Division 1 malocclusion and ANB > 4°, were included. Participants were categorized into two groups, thin (n=35) and thick (n=15) gingival biotypes. Gingival parameters were assessed before and after maxillary incisor retraction using a World Health Organization (WHO) probe also known as the Community Periodontal Index of Treatment Needs (CPITN) probe. Quantitative data, the gingival height, probing depth, and gingival width, were assessed using the Shapiro-Wilk test. Statistical analysis was performed using SPSS with level of significance set at p ≤ 0.05.

Average age of patients was 24.5 years, comprising 40% males and 60% females. Among them, 70% had a thin gingival biotype, and 30% had a thick biotype. Thin biotype patients had lower mean gingival thickness (0.88 mm) and width (3.2 mm) than thick biotype patients (1.25 mm and 3.5 mm, respectively). Probing depth and gingival recession were slightly higher in thin biotypes. THIn the thin biotype group, gingival thickness decreased by 0.06 mm, probing depth increased by 0.2 mm, gingival width reduced by 0.2 mm, and gingival recession rose by 0.2 mm. For the thick biotype, changes were less pronounced, with a decrease in gingival thickness by 0.03 mm, a slight increase in probing depth by 0.1 mm, a reduction in gingival width by 0.1 mm, and an increase in gingival recession by 0.1 mm. After sequential retraction of maxillary teeth patients with a thin biotype showed significant reductions in gingival thickness (p=0.03) and width (p=0.02) with an increase in probing depth (p=0.04) and gingival recession (p=0.01). In contrast, the thick biotype group demonstrated minimal and statistically insignificant changes in these parameters (p > 0.05).

Patients with a thin biotype have increased risk of periodontal recession and reduction of gingival thickness while retraction of anterior teeth. Orthodontic treatments should consider appropriate measures to retract teeth keeping the biotype of gingiva in mind to preserve gingival health.