AClinical Study Of Early Interventions On Fresh Extraction Socket With A Mixture Of Coralline Hydroxyapatite And Autogenous Bone Under Different Ratios

Background:Studies have shown that a reduction in ridge dimensions takes place at the firstmonth after tooth extraction. In particular, loss of the bundle bone results in obvioushorizontal bone loss and vertical ridge reduction on the facial plate. This process ofbone remodeling will aggravate the reduction of soft tissue, creating a clinicalchallenge for the implant surgeries and a burdened patient with higher estheticproblems. The early-stage interventions on fresh extraction socket may aid inpreventing or reducing the physiological resorptive hard tissue and soft tissueprocesses.Objective:The aim of the study was to clinically, histologically and radiologically evaluatethe effects of the fresh extraction socket bone regeneration with mixtures of corallinehydroxyapatite(CHA) and autogenous bone(AB) under different ratios, and theapplied value of autogenous bone in sockets site preservation.Material and methods:60patients were randomly selected, evenly assigned to four different groups:group A(blood clot), group B(CHA), group C(mixture of80%CHA and20%AB)and group D(mixture of50%CHA and50%AB). All samples were subjected toclinical examination, Oral plaster casts and panoramic pantomogram at two timepoints, before tooth extraction and3~4months after socket grafting. The sockets werefilled with biomaterial according to the groupings following atraumatic extraction andthorough socket debridement. After a3~4months follow-up, using a2mm diametertrephine to obtain a6~8mm longitudinal bone core. Using a digital caliper to analyzethe plaster casts, and the tomography datas were conducted by image analysissoftware PACS(Carestream，11.0version), while the histological data were processedby image analysis software ImageJ.Results:1) Differences were significant revealed between the contrast group and the testgroups by oral plaster casts, radiographic and histological analysis(P<0.001). 2) Higher proportion of CHA took more advantages in maintaining the socketvolume, but no statistical variances was observed among the threeprocessings(P>0.05).3) The effects of bone formations under different ratios of CHA and AB were notthe same. A distinct discrimination was found between CHA: AB(50:50) andCHA in osteogenesis(P<0.001), CHA: AB(50:50) and CHA: AB(80:20)showed indifferent whereas(P>0.05). The residual rates on different ratios ofCHAand AB were obviously differentiated(P<0.001).Conclusions:1) Differences were observed between the sockets with and without biomaterialgrafts in the clinical, histological and radiological tissue alterations after3months follow-up, indicating that it would be meaningful to intervene theextraction sockets at early-stage.2) No difference was found in the clinical and radiological tissue alterations withand without autogenous bone except histological differences were found. It isindicated that autogenous bone have effects on the improvement of bone quality.3) It is observed that the application of autogenous bone in sockets site preservationhas a certain value.