ABSTRACT
The aim of this investigation was to study the effect of dentin depth and patient's age on the shear bond strength of one dentin adhesive (ART Bond), using an Instron Universal testing machine at a cross-head speed of 0.5 mm/min. Forty human molar teeth were used and were divided into two main groups, twenty each representing two age groups of patients, i.e., between 20 to 30 years and between 30-40 years of age. Every group was further subdivided into two subgroups of different dentin depths, i.e., superficial and deep. Results were recorded in Kg/Cm2 and converted into MPa units, then tabulated and statistically analyzed. A Duncan's range statistic test at P < or = 0.05 showed statistically significant differences between the bond strength values for both age groups at different dentin depths, with the superficial dentin showing higher bond values, and there were also statistically significant differences between the bond strength values of the two age groups at the same dentin depth, with the older age group showing higher bond values.
Subject(s)
Composite Resins/chemistry , Dentin-Bonding Agents/chemistry , Dentin/drug effects , Maleates/chemistry , Methacrylates/chemistry , Adult , Age Factors , Analysis of Variance , Humans , In Vitro Techniques , Materials Testing/instrumentation , Materials Testing/methods , Materials Testing/statistics & numerical data , Molar , Surface Properties , Tensile StrengthABSTRACT
The aim of this investigation was to compare the shear bond strengths of three dentine adhesives tested using an Instron Universal Testing machine at a crosshead speed of 0.5 mm/min. Sixty human molar teeth were used and divided into 3 equal groups where the occlusal surfaces were ground and adhesives were applied overlaid by composite material. Samples were fixed to the Universal Testing machine. Results were recorded in kg/cm2 and converted into MPa units then tabulated and statistically analyzed. Duncan's multiple range statistic test at p < 0.05 showed no statistically significant difference between the shear bond strength values of Scotchbond 2 and Amalgambond; whereas the shear bond strength values of Scotchbond 2 and Amalgambond were significantly higher than those of Gluma. Scanning electron microscopic examinations at X10 and X2500 magnifications showed a dominant adhesive pattern of failure in the samples treated with Gluma, and a mixture of cohesive and adhesive-cohesive patterns of failures in the samples treated with Scotchbond 2 and cohesive patterns of failures in the samples treated with Scotchbond 2 and Amalgambond.
Subject(s)
Dental Bonding , Dentin-Bonding Agents , Resin Cements , Adult , Composite Resins , Glutaral , Humans , Materials Testing , Methacrylates , Microscopy, Electron, Scanning , Polymethacrylic Acids , Tensile StrengthABSTRACT
Surface roughness is one of the most influential criteria affecting the durability and strength of the adhesive restorative materials to the dentine. This study was carried out to investigate the roughness of the dentine surface after some of the modalities proposed for its treatment prior to application of the DBA. Dentine surface roughness of the sixty teeth divided into 12 groups were tested where the dentine surfaces were denuded and were brought to a similar 600 grit surface roughness then different treatments were carried out using H2O2, CO2 gas laser at 30 and 48 J/cm2 energy densities, EDTA and polyacrylic acid treatments. The dentine surface roughness was determined using a profilometer and the results were digitized and plotted using an AUTO-CAD software and Rolland plotter to compare the effects of the different treatments on the dentine surface roughness of the tested samples. Results revealed that the laser treatment left smooth dentine surface and added further evidences to the simplicity and reliability of the conventional use of EDTA and the polyacrylic acid according to the type of adhesive to be used.
