Influence of Soft Tissue and Crestal Bone Resorption in Moderate Cigarette-Smokers and Nonsmokers: A 5-Year Study.

This study aimed to determine the impact of implant placement depth (bone-level [BL] and subcrestal [SC]) on soft-tissue inflammatory parameters bleeding on probing (BOP), probing depth (PD), and crestal bone resorption (CBR) in moderate cigarette-smokers and nonsmokers at 5 years postplacement. Patient details were recorded, including sex, age, smoking history, duration of implants in function, implant arch location, and daily toothbrushing and flossing habits. Peri-implant BOP, PD, and CBR were measured in all groups, and group comparisons were done; a probability score < .05 was selected as a value for statistical significance. Fifty-three patients (27 smokers, 26 nonsmokers) had BL implants, and 55 patients (28 smokers, 27 nonsmokers) had SC implants. Among all patients, PD was higher in smokers than nonsmokers (P < .05). The peri-implant sites that demonstrated BOP were higher (P < .05) in nonsmokers than smokers. Among smokers, the CBR was higher in those with BL implants than those with SC implants (P < .05). Among nonsmokers, there was a difference in BOP, PD, and CBR at the 5-year follow-up. At 5 years, SC implants demonstrated less CBR than BL implants. Peri-implant PD is higher in smokers than nonsmokers, irrespective of the implant placement depth.