Clinical study on restoration of severe crown defect of molars by endocrowns made of different materials with pulp chamber retention

Objective To compare the clinical efficacy of endocrowns made of three different materials with medullary retainer in the repair of severe molar crown defects. Methods From September 2015 to December 2017, 81 patients (95 molars) with severe crown defects were selected from the Stomatology Department of the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine. They were respectively restored with the polymeric porcelain endocrown (group A ), the zirconia all-ceramic endocrown (group B), or the gold-palladium alloy porcelain endocrown (group C). Follow-up observation was conducted 6 and 12 months after the repair, respectively, to compare the clinical repair effect of the 3 groups. Results There was no significant difference in morphology, marginal staining, marginal fitness, secondary caries and surface texture qualification rate among the 3 groups 6 months after restoration (P>0.05). At 12 months after repair, the incidence of gingival reaction in group C was higher than that in group A and B (P<0.05). The total incidence of complications in group C was higher than that in group A (P<0.05). There were no statistically significant differences in the total incidence of complications between group A and group B or between group B and group C (P>0.05). Conclusions Under the condition of applying pulp chamber retention, the endocrowns made of three different materials have their own advantages and disadvantages in the repair of molar with severe crown defects. The appropriate endocrowns should be selected according to the needs of patients and the actual situation.