OBJECTIVETo evaluate the effects of GLUMA desensitizing bonding system in desensitizing hypersensitivity of vital abutment.

METHODS69 central incisors with vital pulp from 69 patients were randomly divided into A, B and C group. After tooth preparation, group A coated with primer after etching, group B coated with primer after etching cervical dentin only, and group C was control group without special treatment. The cold sensitivity of abutments was tested after coating with primer, after cementation of crown and three months later. Two fresh extracted caries and restoration-free middle incisor were prepared in routine way. The surface of specimen 1 was etched with conditioner and the control specimen 2 was prepared without any special surface treatment. Scanning electron microscope (SEM) observation was used to examine the details on dentin surface.

RESULTSIn all three times of examination, the sensitivities of two experimental groups had been significantly reduced compared with the control group. Immediately after coating, group B were more sensitive than group A (P < 0.05). After cementation of crown and three months later, there was no statistically significant between group A and group B. SEM photomicrograph showed that the smear layer was removed from etched dentine surface with open dentinal tubules.

CONCLUSIONCoating with GLUMA desensitizing bonding system could prevent hypersensitivity of vital abutment.