Long-term stability after nonsurgical treatment of periodontitis

Non-surgical periodontal therapy (NSPT) remains the fundamental approach in periodontal treatment and has been extensively studied over the past decades. Evidence consistently shows that NSPT exerts a substantial and sustained impact on tooth retention and on key surrogate outcomes, including gains in clinical attachment levels, reductions in probing pocket depths and improvements in inflammatory parameters.

To evaluate the long-term (≥5 years) efficacy of non-surgical periodontal therapy and to explore the effect of alternative or adjunctive mechanical methods (e.g., laser, air-polishing devices, etc.) compared to hand, sonic, or ultrasonic instruments in NSPT.

A systematic electronic search was conducted to analyse the scientific literature available by including all potential studies reporting long-term results of the non-surgical periodontal treatment, regardless of study design. To evaluate the effectiveness of alternative protocols for subgingival instrumentation, a systematic electronic sear was also conducted including only randomized clinical trials (RCTs).

27 manuscripts corresponding to 20 investigations reported on the long-term outcomes of non-surgical therapy. Most of the studies showed low incidence of tooth loss, clinical attachment gains at initially deep pockets and probing pocket depth reductions, especially on those patients attending regularly supportive periodontal care (SPC). The use of laser as an alternative to hand instruments or ultrasonic devices, or as adjuncts to subgingival instrumentation has shown conflictive results. Some studies evaluating the adjunctive use of antimicrobial photodynamic therapy have reported modest clinical improvements in the short term (3 to 6 months). Subgingival air-polishing may offer potential benefits for patient comfort and shorter treatment times.

Overall, the available evidence supports NSPT as a reliable and long-lasting treatment option, while emphasizing the need for further research on patient reported outcomes and systemic effects within the long-term framework of comprehensive periodontal treatment.

Non-surgical periodontal therapy is the key tool for treating periodontitis in most patients. The gold standard treatment is subgingival instrumentation using hand- or power-driven instruments, together with regular SPC. Various alternative or adjunctive therapies have been suggested, but the evidence available is limited, particularly in the long term.