Evaluation the fracture resistance and clinical success of prefabricated zirconium crowns on primary teeth

Objective: The purpose of this study is to examine the rate of the retained prefabricated primary zirconium crowns (PPZCs) subjected to chewing simulation test with thermocycling mechanical loading (CSTTML) and evaluate fracture resistance of samples, cemented with four different luting cements. And also we aimed to evaluate the PPZCs' clinical success, retention rate, effect on periodontal health and parental satisfaction. Method: In first part of our study a total of 120 extracted primary molar teeth were restorated using four different luting materials (Bioactive cement, resin cement, glass ionomer cements (GICs), resin modified GICs) with PPZCs, After half of each groups subjected to CSTTML, all the samples subjected to fracture tests and the mean force required to fracture the PPZCs was noted. In the second part of our study was included 60 PPZCs, restored using 4 different luting cements. The study included 60 PPZCs and 12 months of clinical evaluation and parents satisfaction was carried out. Results: After the CSTTML test, in all groups-subjected and non-subjected CSTTML-resin cement groups showed the highest fracture resistance, also there was no statistic difference between GICs (p=0,888). The second clinical part our study, the highest survival rate were belonged to resin-modified GIC, but there was not significantly different between all the groups (p>0,05). When we compared the plaque indices, gingival indices and probing depth results between the PPZCs' and the median overal mouth teeths' results, there was a significant reduction in plaque index values in PPZCs (p<0,05). It was seen that parental satisfaction was high. Conclusion: It has to be considered patient cooperation, durability, retention, easy application and application time for cementetion of PPZCs. When the results of gingival health and parents satisfaction of PPZCs determine, the treatment with PPZCs represents a promising alternative for rehabilitation of multifaced decayed primary molar teeth. Key words: Prefabricated Primary Zirconium Crowns, Luting Cements, Chewing Simulator, Fracture Resistance, Periodontal Indices