January 2021

Aims: To determine the differences in the long-term clinical outcomes between Regeneration (REG) and Conservative Surgery (CS) in infra-bony defects. Materials and Methods: Three databases were searched [PubMed, Medline and Embase] up to April 2019. Following screening, 17 studies were included. Randomized Controlled Clinical Trials, Controlled Clinical Trials and retrospective studies with long-term clinical observations (≥ 24-months) were selected. After subgrouping the studies regarding the grafting material and the used flap, meta-analysis was performed for different outcomes [clinical attachment level gain (CALGain), probing pocket depth reduction (PPDRed), recession increase (RECInc) and bone fill (BF)] at different follow-ups (24-, 36-, 48- to 60- and 120- to 240-months). Results: The time-related meta-analysis favoured REG at every interval for every outcome. In subgroup analysis, enamel matrix derivative (EMD) performed significantly better for both CALGain [24- (p<0.0001), 36- (p=0.02) and 60-months (p<0.00001)] and PPDRed [24- (p=0.0004), 36- (p=0.003) and 60-months (p<0.00001)]. For Ceramic Grafts (CGs), CALGain at 48-months (p<0.00001) and PPDRed at 24- (p=0.0006), 36- (p<0.00001) and 48-months (p<0.00001) follow-up showed better results. Conclusion: The better outcomes from REG using EMD or CGs can be maintained for a longer duration, suggesting a potential longevity of the occurred healing.