Comparative Study Of The Alveolar Ridge Splitting Technique Combined With Guided Bone Regeneration In The Anterior Maxilla

Purpose: This retrospective controlled study aimed to estimate the radiographic and clinical outcomes of the alveolar ridge splitting(ARS)technique combined with guided bone regeneration(GBR)and compare its efficacy with GBR alone in the anterior maxilla.Methods: From June 2014 to June 2017,patients who had received the maxillary anterior implantation by ARS technique combined with GBR or by GBR alone were selected and divided into two groups: ARS combined with GBR(ARS group)and GBR alone(GBR group).Buccal bone loss at 0-4 mm below the implant shoulder at 6 months after surgery,bucco-lingual implant angulation and marginal bone loss after 1-year function loading of implants were evaluated with radiographic analysis.Patient reported outcomes(PROs)were used to compare patient satisfaction on implant-supported restorations of two groups.Additionally,this study evaluated the clinical examination results of soft tissues around the implant and pink esthetic score(PES)of two groups.Results: A total of 80 patients with 100 implants were include,40 patients with 51 implants in the ARS group and 40 patients with 49 implants in the GBR group.After 6 months of bone healing,obvious diminution of buccal bone happened within each group(P<0.001).The buccal bone thickness at 0-4 mm levels in the ARS group had no statistical disparities compared with the GBR group(P>0.05),except buccal bone thickness in the 4-mm level at 6 months after surgery(P=0.007).Interestingly,when considering the diminish of buccal bone thickness at different levels,inter-group comparisons revealed statistical disparities(except in the 1-mm level)in favor the ARS group(P<0.05).The mean value of mesial marginal bone loss is less in the ARS group than that in the GBR group(P<0.05).Meanwhile,the implant angulations and values of PROs in both groups had no statistical disparities(P>0.05).Clinical examinations showed that most patients had good oral health conditions.When compared with the GBR group,the mean values of probing depth in the ARS group had no statistical disparities(P>0.05),except the probing depth at the mid-buccal site which favors the ARS group(P=0.039).In addition,there were no disparities in the width of keratinized mucosa and values of PES(P>0.05).Conclusion: According to the outcomes of this study,compared with GBR alone,alveolar ridge splitting technique combined with GBR had less diminish of the buccal bone thickness and mesial marginal bone loss,which is a safe and effective surgical method for the treatment of insufficient alveolar bone width in the anterior maxilla.