Evaluation of periodontal parameters on Removable Partial Denture abutment teeth with direct and indirect retainers: A 48-month follow-up.

Objectives: To evaluate periodontal parameters of abutment teeth and interproximal sites, in patients with mandibular class I Kennedy Removable Partial Dentures (RPD), after 4 years of periodontal treatment.

Methods: Fourteen patients with periodontal disease were treated and evaluated for the following parameters: plaque index (PI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), clinical attachment loss (CAL) and keratinized mucosa (KM). Parameters were compared between abutment teeth with direct and indirect retainers at all time-points. Periodontal maintenance was recorded at 6, 18 and 48 months. Data were analyzed using the Friedman and Wilcoxon Tests.

Results: Most patients (n=11; 78.6%) included were female and had a mean age of 66 years (± 7.8). After 48 months, a significant reduction was only observed in PI for both abutment teeth; in contrast, PD, GR, CAL and KM all increased by the end of the study. BOP increased at 48 months for the abutment teeth with direct retainers. The distal site of the abutment teeth with direct retainers presented higher values for GR and CAL.

Conclusions: Non-surgical periodontal therapy was effective during the first 18 months, but periodontal conditions were worse at 48 months after therapy. The distal sites of abutment teeth with direct retainers presented the worst periodontal conditions.