ĐẶC ĐIỂM HÌNH THÁI CỦA PHỨC HỢP RĂNG NƯỚU VÀ MỨC ĐỘ TỤT GAI NƯỚU CỦA VÙNG RĂNG TRƯỚC HÀM TRÊN

Abstract

Background: Dentogingival unit consists of gingival, gingival sulcus, junctional epithelium and connective tissue attachment, and the last two components create the biologic width which is the subject of interest to dentistry. The biologic width and papilla preservation are always the major concern of clinicians. This article’s objective is to screen the morphological characteristics of the dentogingival unit and the relation between those with the level of papilla recession in the upper anterior teeth using Cone-beam Computed Tomography (CBCT), direct measurement and 3D intraoral scanner. Methods: Cross-sectional descriptive study: 196 upper anterior teeth including left and right canines, left and right lateral incisors, and left and right central incisors is taken from 32 students aged from 18-40. Research subjects will be scanned intraorally and taking a CBCT with cheek retractor and cone gutta-percha putting inside the gingival sulcus. All of the characteristics of dentogingival unit will be screened including: distance from bone crest to the gingival margin, the bone crest thickness, distance from cement-enamel junction (CEJ) to gingival margin, biologic width, free gingival thickness, distance from contact point to the bone crest between two teeth, keratinized gingival width, the incidence of papilla recession. This article also wants to identify the correlation between those characteristics with the level of papilla recession in upper anterior teeth.     Results: Distance from bone crest to gingival margin: 3,25 ± 0,63 mm, bone crest thickness: 0,76 ± 0,35 mm, distance from CEJ to gingival margin: 1,25 ± 0,76 mm, free gingival thickness in male: 0,71 ± 0,12 mm and in female: 0,64 ± 0,16 mm, keratinized gingival width: 5,5 ± 1,5 mm, biologic width: 2,17 ± 0,68 mm, distance from contact point to the bone crest: 4,50 ± 0,81 mm. Incidence of papilla recession in upper anterior teeth is 37,5%. When the distance from contact point to the bone crest is 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, the fully presence papilla incidence will be 100%, 95,5%, 77,4%, 38,9% and 0%, respectively. Conclusion: The characteristics of dentogingival unit can be diagnosed by using CBCT combined with cheek retractor and cone gutta-percha. There is a close correlation between the distance from contact point to bone crest with the papilla recession incidence.