Peri-implant soft tissue status and crestal bone loss around immediately-loaded narrow-diameter implants placed in cigarette-smokers: 6-year follow-up results

Abstract

Background: It is hypothesized that in the long-term, soft tissue inflammation (reflected by increased scores of peri-implant probing-depth [PD]) and crestal bone loss (CBL) is higher in cigarette-smoker than nonsmokers with narrow diameter implants (NDIs).

Purpose: The aim of the present 6-years' follow-up clinical observational study was to compare the peri-implant soft tissue inflammatory parameters (plaque index [PI], gingival index [GI], and PD) and CBL around immediately-loaded NDIs placed in cigarette-smokers and nonsmokers.

Materials and methods: In all groups, peri-implant GI, PI and PD were measured on six sites (distolingual/palatal, mesiolingual/palatal mesiobuccal, distobuccal, midlingual/palatal, and midbuccal) per implant. The CBL was gauged on digital bitewing x-rays, which were standardized using the long cone paralleling technique. CBL was demarcated as the vertical distance from 2 mm below the implant-abutment connection to the most crestally-positioned alveolar bone.

Results: All study-participants were male. Twenty-six cigarette smokers and twenty-five nonsmokers were included. The mean age of cigarette-smokers and nonsmokers was 45.5 ± 10.3 and 47.4 ± 9.4 years, respectively. Cigarette-smokers had a smoking history of 10.6 ± 0.4 pack years. Family history of tobacco usage was more often reported by cigarette-smokers (57.7%) than nonsmokers (20%). All cigarette-smokers and nonsmokers were aware that smoking is a risk-factor of loss of implant. Three (11.5%) of cigarette-smokers reported that they have attempted to quit smoking and 76.9% of cigarette-smokers (n = 20) reported that they had no intention to quit smoking in the future. The peri-implant P-I (P < .01), PD (P < .01) and mesial (P < .01), and distal (P < .01) CBL were significantly high in cigarette-smokers compared with nonsmokers. There was no statistically significant difference in GI among the groups.

Conclusion: Cigarette-smoking enhances peri-implant soft tissue inflammation and increases CBL around immediately-loaded NDIs.

Keywords: alveolar bone loss; dental implant; inflammation; narrow diameter; smoking.