Laboratory study of the quality of marginal attachment of direct composite restorations to hard dental tissues

Background. Destruction of natural tooth crowns by caries and non-carious lesions is an urgent medical and social problem. This pathology leads to a large number of complications. There are many methods for restoring significant and total defects in the crown part of the teeth. Each method has its advantages and disadvantages. Direct methods for restoring hard tooth tissues remain relevant for restoring defects in tooth crowns. Composite materials are often used for this. We have proposed a method for improving the adhesive connection of the composite with hard tooth tissues. We study the advantages of alcohol technology for applying an adhesive system. We conducted laboratory studies to study the marginal fit of direct composite restorations to hard tooth tissues. Purpose – of the work is to conduct a comparative analysis of the results of laboratory studies of the quality of marginal adhesion of direct composite restorations to hard dental tissues when restoring a defect in the crown of a tooth: without the use of ethanol and with the use of ethanol before applying the adhesive system. Materials and Methods. The quality of the marginal fit of direct composite restorations to hard tissues was studied by micro-penetration of the dye to their junction. The study used human premolars, removed for medical reasons from the upper and lower jaws of adults under the age of forty. The teeth were divided into two experimental groups. In all of them, a defect was created that reached the pulp chamber. The defect was restored with composite material using two technologies: without the use of ethanol before applying the adhesive system and with its use. Results. The results of the study of samples from the first experimental group (without the use of ethanol) showed a good result of the quality of the connectionof the composite material with hard dental tissues due to the low degree of micropenetration of the dye. The values of the micro-penetration of the dye among the samples from the second experimental group, where ethanol was used, were also good. The degree of micropenetration of the dye was lower than in the samples from the first group. Conclusions. Comparison of the data obtained when studying the micro-penetration of the dye in the experimental groups shows a statistically significant difference (p < 0.05). The value of this indicator among the samples from the second experimental group is not inferior to the results in the first experimental group. The results are lower. This indicates an improvement in the sealing of the connection of composite restorations with hard dental tissues when using ethanol to introduce the adhesive system.