The distribution and the influencing factors of the teeth with residual pockets in periodontitis stage III–IV treated by non- surgical periodontal treatment

Abstract

Background Periodontitis is a chronic multi-factorial infectious disease, and there is a significant difference in the prognosis of severe periodontitis patients after non-surgical periodontal treatment. Therefore, a retrospective study was conducted to find common and specific factors affecting the prognosis of periodontitis stage III-IV after non-surgical periodontal treatment according to various tooth sites.Methods A total of 977 teeth from 266 patients of periodontitis stage III-IV were enrolled, including 330 anterior teeth, 362 maxillary posterior teeth and 285 mandibular posterior teeth. The enrolled teeth were divided into two groups according to the residual pockets (PD ≥ 5 mm) at 3 months post-treatment. The association of risk factors with the prognosis of periodontitis stage III-IV were analyzed with multivariate analysis. All tests were two-sided and parameters were statistically significant (P < 0.05).Results The PD values of each site and the deepest PD values of each tooth were significantly decreased at 3 months post-treatment, and the residual pockets were mainly distributed in mesio/disto-buccal and mesio/disto-lingual. The multivariate analysis revealed that gender, probing depth (PD), sulcus bleeding index (SBI) and plaque index (PLI) at baseline and crown-root ratio in anterior teeth had significant correlation with periodontitis stage III-IV (P < 0.05). In maxillary posterior teeth the significant factors were smoking, PD, PLI and furcation involvement (FI) at baseline, PLI at 3 months post-treatment, grades of periodontitis and crown-root ratio. And PD, PLI and FI at baseline, PLI at 3 months post-treatment and crown-root were significant in mandibular posterior teeth.Conclusions The mean PD and PLI at baseline and crown-root ratio were common prognostic factors of anterior teeth, maxillary posterior teeth and mandibular posterior teeth. The gender and SBI at baseline were specific prognostic factors of anterior teeth. The common prognostic factors of posterior teeth were FI at baseline and PLI at 3 months post-treatment. While the specific prognostic factors of maxillary posterior teeth were smoking and the grades of periodontitis compared with mandibular posterior teeth .