Influence of incisor inclination and position on the gingival biotype of orthodontic patients

Abstract

Introduction: The inclination and position of incisors are important factors influencing orthodontic planning. Labial or lingual inclination of lower incisors can result in changes of gum levels in the lower labial or lingual attached mucosa. Such gingival recession can be generalized or localized, affecting an area of ​​the tooth or more, and could lead to an aesthetic impairment. Hence the aim of this study was to evaluate the association of gingival biotypes with the position and inclination of the maxillary and mandibular incisor.

Material and Methods: The sample included in this cross- sectional study consisted of 110 orthodontic patients (45 men and 65 women) seeking orthodontic treatment at the Khyber College of Dentistry, Peshawar. Gingival biotype was evaluated with Michigan - O probe. Inclination and position of the upper and lower incisors were evaluated on lateral cephalometric radiographs. The measurements used in the analysis were as follows; For maxillary incisor inclination and position, UI-NA angle and distance were used respectively. For mandibular incisor inclination and position, incisor – mandibular plane angle (IMPA) and mandibular incisor to points N and B (LI-NB) were used respectively. Data were compiled and analyzed using the Statistical Package for Social Sciences (SPSS version 20).

Results: The average age in years of the study sample was 23.56 (± 2.55). No significant difference was found between thin (23.23 ± 2.63) and thick (23.81 ± 2.47) gingival biotypes (p = 0.18). Frequency of thin gingival biotype was significantly higher in women than in men in both upper and lower incisors (p = 0.0001).

Conclusions: Gingival biotypes (thick and thin) show statistical significance by gender only. Inclination and position of incisors in maxilla were non-significantly associated with the type of gingival biotype.