Periodontal regeneration compared with access flap surgery in human intra-bony defects 20-year follow-up of a randomized clinical trial: tooth retention, periodontitis recurrence and costs.

AIM: Compare the long-term outcomes and costs of three treatment modalities in intra-bony defects. MATERIALS AND METHODS: Forty-five intra-bony defects in 45 patients had been randomly allocated to receive: modified papilla preservation technique with titanium-reinforced expanded-polytetrafluoroethylene (ePTFE) membranes (MPPT Tit, N = 15); access flap with expanded-PTFE membranes (Flap-ePTFE, N = 15) and access flap alone (Flap, N = 15). Supportive periodontal care (SPC) was provided monthly for 1 year, then every 3 months for 20 years. Periodontal therapy was delivered to sites showing recurrences. RESULTS: Forty-one patients complied with SPC. Four subjects were lost to follow-up. Clinical attachment-level differences between 1 and 20 years were -0.1 +/- 0.3 mm (p = 0.58) in the MPPT Tit; -0.5 +/- 0.1 mm (p = 0.003) in the Flap-ePTFE and -1.7 +/- 0.4 mm (p < 0.001) in the Flap. At 20 years, sites treated with Flap showed greater attachment loss compared to MPPT Tit (1.4 +/- 0.4 mm; p = 0.008) and to Flap-ePTFE (1.1 +/- 0.4 mm; p = 0.03). Flap group lost two treated teeth. Five episodes of recurrences occurred in the MPPT Tit, six in the Flap-ePTFE and fifteen in the Flap group. Residual pocket depth at 1-year was significantly correlated with the number of recurrences (p = 0.002). Sites treated with flap had greater OR for recurrences and higher costs of re-intervention than regenerated sites over a 20-year follow-up period with SPC. CONCLUSIONS: Regeneration provided better long-term benefits than Flap: no tooth loss, less periodontitis progression and less expense from re-intervention over a 20-year period. These benefits need to be interpreted in the context of higher immediate costs associated with regenerative treatment. These initial observations need to be extended to larger groups and broader clinical settings.