Factors affecting soft tissue level around anterior maxillary single-tooth implants.
BACKGROUND
Peri-implant soft tissue recession is a major esthetic concern for the anterior implants. The aim of this study was to determine the factors that affected the facial marginal mucosal level and papilla level around single-tooth implants in the anterior maxilla.


METHODS
Forty single-tooth implants in the anterior maxilla were studied. Variables possibly associated with the soft tissue level were obtained from clinical measurements, study models, peri-apical radiographs, and computerized tomograms. Fisher's exact test, analysis of variance, and binary logistic regression analysis were used to determine the influence of each factor on the facial marginal mucosal level and papilla level.


RESULTS
The majority of the implants (75%) replaced the upper central incisors. The facial mucosal margin of the implant was 0.5+/-0.9 mm more apical than that of the contralateral tooth. Half or more of papilla fill was observed in 89% of the samples. More apical level of the facial mucosal margin at the implant sites was significantly influenced by many factors including a thin peri-implant biotype, a proclined implant fixture angle, more apical level of the facial bone crest, increased distance from the contact point to the bone crest, contact point to the platform, and contact point to implant bone. A thin biotype was the most significant factor in determining the facial marginal mucosal level. Increased distance from the contact point to the bone crest was the only factor significantly associated with less papilla fill.


CONCLUSIONS
The papilla level around single-tooth implants in the anterior maxilla was mainly influenced by the interproximal bone crest level of the adjacent tooth. Facial marginal mucosal level, on the other hand, was affected by multiple factors including the peri-implant biotype, the facial bone crest level, the implant fixture angle, the interproximal bone crest level, the depth of implant platform, and the level of first bone to implant contact.
Nisapakultorn
Kanokwan
K
Department of Periodontology, Faculty of Dentistry, Chulalongkorn University, Patumwan, Bangkok, Thailand. nisa0003@hotmail.com
Suphanantachat
Supreda
S
Silkosessak
Onanong
O
Rattanamongkolgul
Suthee
S
D000539:Alveolar Process / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D019250:Dental Implants, Single-Tooth / Q000009:adverse effects; D005260:Female; D005881:Gingiva / Q000033:anatomy & histology*; D005889:Gingival Recession / Q000209:etiology*; D006801:Humans; D007180:Incisor; D016015:Logistic Models; D008297:Male; D008437:Maxilla; D008875:Middle Aged; D009061:Mouth Mucosa / Q000033:anatomy & histology*; D011859:Radiography