Extraction socket preservation graft prior to implant placement with calcium sulfate hemihydrate and platelet-rich plasma: A clinical and histomorphometry study in human subjects

Purpose. The aim of this investigation was to evaluate the combination of medical grade calcium sulfate hemihydrate (MGCSH) and platelet-rich plasma (PRP) for extraction socket preservation prior to implant placement.;Materials and methods. This study was a single-site, randomized, controlled investigation. Sixteen patients with a nonrestorable single-tooth required to be extracted followed by implant placement were enrolled in the study. Sockets were required to have all remaining intact walls. After tooth extraction, eight patients received medical grade calcium sulfate hemihydrate (DentoGen) mixed with platelet-rich plasma (PRP) in the extraction sockets (test group), and eight patients received collagen resorbable plug dressing material (ACE Surgical Supply Inc.), (control group). At the time of extraction and 3 months later (at implant placement surgery), vertical and horizontal socket dimensions were measured. Bone core samples were retrieved from the center of the healed socket prior to implant placement for histomorphometric analysis.;Results. Independent student two samples t-test was used to process the data using Statistical Package for the Social Sciences software program (SPSS).;The results indicated that there was a statistical significant difference between the two groups based on histomorphometric analysis (p<0.05). New bone regeneration was greater in sockets grafted with medical grade calcium sulfate hemihydrate (DentoGen) mixed with platelet rich plasma than collagen resorbable plug. After healing time of 3 months, vital bone percentage present from trephined core samples from the center of the grafted socket was greater in the test group 66.5% +/- 10.4% compared to 38.9% +/- 9.9% in the control group as determined by histomorphometric analysis (p=0.002). There was no statistical significant difference in the amount of vertical and horizontal bone resorption (p>0.05). The vertical bone regeneration in the test group at mid-buccal bone was +0.63 mm +/- 2.10 mm, mid-lingual was +0.13 mm +/- 1.25 mm, mid-mesial was -0.13 mm +/- 0.99 mm, and mid-distal was -0.13 mm +/- 1.13 mm, compared to the control group at mid-buccal was -1.29 mm +/- 3.15 mm, mid-lingual was -1.29 mm +/- 1.11 mm, mid-mesial was -0.57 mm +/- 1.40 mm, and mid-distal -0.29 mm +/- 1.11 mm based on the clinical measurements. Buccolingual width resorption was -1.66 mm +/- 1.36 mm in the test group compared to -1.75 mm +/- 0.63 mm in the control group. There was no statistical significant difference in vertical bone regeneration between groups but was more pronounced at the control sites than at the test sites (-0.86 mm +/- 0.73 mm amount of vertical bone resorbed in the control group versus +0.19 mm +/- 0.95 mm the amount of vertical bone gained in the test group). Radiographic measurements confirmed the mesial and distal clinical measurements in both groups with no statistically significant difference. For the test group, the amount of vertical bone resorption at the mesial site was -0.43 mm +/- 0.37 mm and at the distal site was -0.45 mm +/- 0.66 mm. For the control group, vertical bone resorption at the mesial site was -0.53 +/- 0.27 mm and at the distal site was -0.63 +/- 0.40 mm.;Conclusions. Medical grade calcium sulfate hemihydrate (DentoGen) mixed with platelet rich plasma showed an increased vital bone volume with accelerated bone healing. After a healing time of 3 months, vital bone percentage present from trephined core samples from center of the grafted socket was higher in test group as determined by histomorphometric.;Key words: bone regeneration, calcium sulfate, collagen plug, dental implant, histomorphometry, socket preservation.