| BACKGROUNDAlong with development t of oral implantology, dental implantation was accepted bylarge majority of dentists and patients. However, due to periodontal disease, injury andsome other reasons, most patients have excessive assimilation of alveolar bone in theedentulous area, which cause difficulties for treatments of implant prosthesis. In order tosolve insufficient bone mass in edentulous ridge, bone augmentation technology is used,which includes sinus floor elevation technique, guided bone regeneration, distractiontechnique, onlay grafting techniques and so on. Although these surgical options have beenquite mature and have a good chance of success, it certainly increases postoperativecomplications, prolong treatment duration and improve treatment expenses. Fortunately,choosing implant-supported fixed partial dentures with cantilevers (ICFDPs) is a effectiveway to avoid the bone defect region, decrease the complexity of surgery.In theory, ICFDPs can change stress mode of implant, increase lateral and vertical load, which cause stresses concentration for implant neck, and these adverse mechanicalfactors may lead to marginal bone loss around implants and even implant failure. With thedeepening of research, it has been reported that ICFDPs was feasible under a variety ofconditions and did not result in marginal bone loss around implants.However, relationship between effectiveness of implant and relevant factors ofcantilever design is still worthy of studying and discussion.OBJECTIVESThis study included two sections. The first part mainly evaluated the clinicaleffects of implantation and restoration by analyzing clinical data with ICFDPs whichincluded cumulative survival rate, biological complications mechanical complications.The second part mainly evaluated situation of marginal bone loss around implants throughanalyzing the imaging information of all the cases.METHODS AND CONTENTClinical data and imaging information of58cases with ICFDPs were collected,which included60prostheses and103implants between Jan.2005to Jun.2011. Thefollow-up evaluation included the cumulative survival rate (CSR) of implants andprostheses, modified sulcus bleeding index (mSBI), modified plaque index (mPLI), depthof the probe (PD) and marginal bone loss(MBL). All the statistic results were analyzed bySPSS16.0.RESULTS1. The average follow-up period was31.5months. The cumulative survival rate is100%for implants in the follow-up period, and92.3%for prostheses. The average ofmPLI is0.95±0.62(0for the minimum,2for the maximum). The average of mSBI is0.34±0.42(0for the minimum,2for the maximum). The average of PD is2.87±0.73mm(1mm for the minimum,5.04mm for the maximum).14implants had peri-implantmucositis. Eleven prostheses had mechanical complications, and eight among them hadscrew loosed and one had screw broken,which accounted for53%of prostheses withscrew fixation, the remaining two had ceramic fracture without missing of adjacency.2. The efficiency of early treatment was100%. The average healing time was5.33 months, and the marginal bone loss was0.63±0.52mm during the healing time. Afterfinishing restoration, the marginal bone loss was0.09±0.13mm, and no statisticallysignificant difference was observed between implants with far-end(0.08±0.12mm) andnear-end (0.08±0.12mm) cantilevers.CONCLUTIONSThis retrospective study suggested that ICFDPs had a high cumulative survival ratefor implants and prostheses. It was an effective way to avoid marginal bone loss zone,shorten time without tooth, and reduce surgery complexity and postoperativecomplications by using ICFDPs reasonably. ICFDPs were reliable which could be chosenas a technique of planting design clinically. However, due to high rate of mechanicalcomplications by retention mode of screw, it should be aware of choosing this method. |
PDF Full Text Request