A Retrospective Study Of Influence Of Platform Switching On Peri-implant Bone Loss

Objective: Marginal bone loss occurs following dental implant placement. In thelast decades, it has been suggested that marginal bone loss is dependent upon a series offactors, including the implant neck surface characteristics and the implant-abutmentconnection.The implant marginal bone level is one of the important standard ofevaluating implant success. This study by using X-ray to compare the influence of themarginal bone loss between platform switching implant and butt-joint implant withfixed prostheses at the corresponding period in a year.Material and Methods: Totally95patients with implant prosthesis were collected inYantai Stomatological Hospital from September2009to November2011.41patientsreceived53Certain PREVALL platform switching implants,54patients received88Full OSSEOTITE Tapered Certain butt-joint implants.The marginal bone loss weremeasured on radiograph at the timepoints of implant placement,prosthesis placement,6months after loading and12months after loading.Use Multivariate Regression Analysisto estimate the influence of the age,gender and implant sites of patients.Result:95patients that received141dental implants were included:38%platformswitching group and62%butt-joint group. At the timepoints of implantplacement,prosthesis placement,6months after loading and12months after loading,themean marginal bone loss of platform switching implant and butt-joint implant were（0.00±0.00）,（0.08±0.04）,（0.24±0.16）,（0.36±0.19）mm and（0.00±0.01），（0.18±0.12），（0.65±0.38），（0.79±0.41）mm.The marginal bone loss of two groups hadsignificant difference（P＜0.01）. At the timepoints of implant placement,prosthesisplacement,6months after loading and12months after loading,the mean marginal boneloss of3.25mm and4.0mm platform switching implants were （0.00±0.00）,（0.07±0.05）（,0.21±0.10）（,0.42±0.19）mm and（0.00±0.00）（,0.09±0.08）（,0.17±0.09）,（0.29±0.14） mm. These differences between two groups were statistically significant(P=0.03).Conclusion:Platform switching implant have the significant advantage aboutreducing marginal bone loss compare to butt-joint implant.As the implant diameterincreases, the implant marginal bone loss is less in the platform switching group.