Retention assessment of fixed partial denture restoring upper first premolar with four different designs

Abstract

When restoring a missing teeth posteriorly most dentist concerning on function more than esthetic , while when restore a missing anterior teeth concerning more on esthetic but in restoring a missing premolar we have to combine both esthetic and function because we have one abutment on posterior and another on anterior area . Implant retained restoration not available to all patients because of cost, medical or dental related reasons. Each type or restoration has its advantages and dis advantages so careful examination and evaluation to decide which type of restoration used to restore a missing tooth on premolar area to combine both esthetic and function . The purpose of this vitro study is to assessment the retention of 4 different designs restoring upper premolar. Group 1(full coverage), group2 (cantilever), group 3 (resin bonded bridges) and group 4(hybrid group) . With two different surface treatment sandblasting or sandblasting and application of metal primer . Summary and Conclusions 127 40 fixed partial prosthesis were divided into four groups each group were subdivided into two groups , 10 bridges of each design 5 treated with sandblasting alone and 5 treated with sandblasting and metal primer . Fixed partial dentures cemented to corresponding epoxy casts by dual cured resin cemented pull out test were done to evaluate the retention of each group . Within the limitations of the present study and based on the findings of this study and its statistical analysis it has been concluded that : (1) Conventional fixed fixed design showed the best retention followed by cantilever design followed by hybrid design meanwhile the resin bonded design showed the least retention . (2) Surface treatment of fitting surface using sandblasting then metal primer application had significantly improved the retention regardless the bridge design . (3) Neither bridge design nor surface treatment affected mode of failure ,where mixed type of failure was observed in all groups .