Ridge preservation in molar extraction sites with an open-healing approach: A randomized controlled clinical trial.

Abstract

To determine the effect of alveolar ridge preservation (ARP) in molar sites without primary flap closure. Three groups were established: extraction sockets grafted with deproteinized bovine bone mineral containing 10% collagen (DBBM-C) and covered by a native bilayer collagen membrane (NBCM) (test group 1), sockets grafted with DBBM-C only (test group 2), and sockets that healed naturally (control group). Primary flap closure was not attempted. Conebeam computed tomography scans were obtained immediately and then 4months after ARP. A biopsy was performed. The change of the marginal bone level was measured. There was significantly less horizontal resorption in test group 1 than in the control group at levels 1mm (-1.02±0.88 [mean±SD] vs. -4.44±3.71mm) and 3mm (-0.31±1.51 vs. -2.27±1.15mm) below the crest, and significantly less vertical reduction in the midcrestal area in test group 1 than in test group 2 (-0.25±0.95 vs. -1.15±1.63mm) (p<.05). There were no significant differences between test groups in clinical and histomorphometric measurements. All groups exhibited stable marginal bone levels after 1year of loading. Alveolar ridge preservation without primary flap closure in molar areas was effective in minimizing ridge resorption and facilitated implant treatment.