In vitro Testing of Experimental and Commercial Bracket Bonding Materials

Abstract

The aims of our study were to assess the cytotoxic effect of five orthodontic bonding materials, in vitro, on HUVECs to study the induction of apoptosis and inflammatory response generated to assess the shear-bond strength of the 5 tested materials in order to quantify their performance. Standardized samples from each material were obtained and incubated with HUVEC cells for 24 and 72 h immersed in complete medium. Cell viability was determined by means of MTS method. Active caspase 3 and TNFa protein levels were measured through ELISA techniques. The shear-bond strength was tested on 60 extracted premolars which were bonded with the same type of bracket, using the 5 different materials. Statistical analysis Student T-tests, Chi-square and Anova tests were used for results interpretation. Cell viability was decreased with material exposure in a time dependent manner. All materials exerted cytotoxic effects, the experimental materials showed a significantly higher decrease in cell viability at the 72 h reading. Shear Bond strength was superior for the resin commercial bracket-bonding materials. The study shows that orthodontic adhesives� cytotoxicity and physical performance is related to their chemical properties and proves that all orthodontic practitioners should use freely their material of choice on condition they are aware of all its� properties.

The Use of Diacrylic Resins in Dental Restorations

“…Recent studies shows that a thin layer of fluid composite (0.5-1mm) has a superior marginal quality; the use of fluid composite liners can reduce the value of microinfiltrations in composite restorations, which is explained by the high percentage of the organic matrix of the fluid composite which increases the stress of shrinkage [19,20].…”

“…Of utmost importance are the quality of the polymerization process and the shrinkage of the outlet, two issues that are currently unresolved in the treatment of odontal lesions with DCR [18][19][20][21][22][23]. The objective of the research is to evaluate the marginal microinfiltrations in composite resin restorations, depending on different restorative techniques at the level of the class II cavities.…”

Morphofunctional Features in Angle Second Class Malocclusion on Dental Gypsum Models

“…The dental arch is defined by: size and shape. The interest in knowing this sector of the stomatognate system is determined by: the relations established between the dental arcade and the cranio-facial structures, the fact that the dental arcade often reacts, compensating for the disequilibrium at the skeletal level, and, importantly, that the dental intra-arch harmony has consequences on dental occlusion [11][12][13][14][15].Researchers focused on the study of the relationship between the cranio-facial structures and the size of the dental arch in the subjects with malocclusions [16][17][18], finding that the maxillary dental arcade in class II/1…”

“…The dental arch is defined by: size and shape. The interest in knowing this sector of the stomatognate system is determined by: the relations established between the dental arcade and the cranio-facial structures, the fact that the dental arcade often reacts, compensating for the disequilibrium at the skeletal level, and, importantly, that the dental intra-arch harmony has consequences on dental occlusion [11][12][13][14][15].…”