Minimally invasive non-surgical therapy (MINST) in stage III periodontitis patients: 6-month results of a split-mouth, randomised controlled clinical trial

OBJECTIVES: To determine if minimally invasive non-surgical therapy (MINST) outperforms classical non-surgical periodontal therapy for stage III periodontitis with primarily suprabony (horizontal) type defects. MATERIALS AND METHODS: In a split-mouth randomised controlled trial, 20 patients’ dental quadrants were randomly assigned to MINST or classical non-surgical treatment. The primary outcome variable was the number of sites with probing pocket depth ≥ 5 mm and BOP. Treatment method, tooth type, smoking status, and gender were evaluated using a multivariate multilevel logistic regression model. RESULTS: After 6 months, the percentage of sites with PD ≥ 5 mm and BOP that healed (MINST = 75.5%; control group = 74.1%; p = 0.98), and the median number of persisting sites (MINST: 6.5, control group: 7.0; p = 0.925) were similar in both groups. In the test and control groups, respectively, median probing pocket depths (2.0 mm vs. 2.1 mm) and clinical attachment level (1.7 mm vs. 2.0 mm) changed significantly (p < 0.05) but similarly. Significantly less gingival recession occurred in the MINST group’s deep molar pockets compared to the control group (p = 0.037). Men (OR = 0.52, p = 0.014) and non-molars (OR = 3.84, p 0.001) had altered odds for healing of sites with PD ≥ 5 mm and BOP. CONCLUSIONS: MINST reduces gingival recession associated with molar teeth, although it performs similarly to traditional non-surgical therapy in treating stage III periodontitis with predominately horizontal-type defects. CLINICAL RELEVANCE: MINST performs similarly to non-surgical periodontal therapy in stage III periodontitis with predominantly suprabony defects. TRIAL REGISTRATION: Clinicaltrials.gov (NCT04036513) on June 29, 2019. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00784-023-04994-4.