RESUMEN
Objective: To observe the influence of keratinized mucosa on peri-implant soft tissue health and stability after implant treatment among patients with chronic periodontitis. Methods: Fifty-eight patients with chronic periodontitis (158 implants) who received implant treatment were enrolled from Aug. 2010 to Nov. 2013. The soft tissue conditions were observed, the peri-implant disease rate and mucosa recession rate were compared between patients in different keratinized mucosa groups. Results: The differences of rates of peri-implant mucositis and peri-implatitis between the narrow keratinized mucosa (NKM) group and wide keratinized mucosa (WKM) group were not statistically significant (P=0.862, P=0.625). The effects of the width of the keratinized mucosa on modified plaque index and modified bleeding index were not significant (P=0.826, P=0.913). When the width of the keratinized mucosa ≥ 2 mm, the recession of mucosa is not evident. The recession incidence of the thick and wide mucosa was 12.86%, which was significantly lower than that of the thin and wide mucosa (33.33%) and that of thick and narrow mucosa (40.63%) (P=0.049, P=0.002). Conclusion: Keratinized mucosa has a positive effect on peri-implant tissue stability among patients with chronic periodontitis susceptibility. The keratinized mucosa with sufficient width can prevent the mucosa from recession.