Restorative materials are experiencing an extensive upgrade thanks to the use of chairside Computer-aided design/computer-assisted manufacturing (CAD/CAM) restorations. Therefore, due to the variety offered in the market, choosing the best material could be puzzling for the practitioner. The clinical outcome of the restoration is influenced mainly by the material and its handling than by the fabrication process (i.e., CAD/CAM). Information on the restorative materials performances can be difficult to gather and compare. The aim of this article is to provide an overview of chairside CAD/CAM materials, their classification, and clinically relevant aspects that enable the reader to select the most appropriate material for predictable success.
This study compares the effect of different handpieces (turbine, high-speed electric handpiece and piezoelectric device) on surface roughness of enamel and dentin when using diamond-coated working tips and burs of the same grit size. The experiment was conducted on 15 extracted first molars from patients aged 45 to 60 years. The occlusal portion was removed using a diamond-coated water wheel and then refined with a 120–130 μm grit bur in order to obtain a flat surface with an adequate exposition of the dentin core. Each surface was divided into three portions and every portion was finished with one of the three tested instruments. The rotary burs and piezoelectric tips had the same grit size (60 μm), and the load on handpiece during preparation never exceeded 150 g. Roughness parameters (Ra, Rsk, Rku) were recorded with a profilometer, and a SEM analysis of treated surfaces and working tips was conducted. Ra and Rsk differed significantly between enamel and dentin only after using turbine (p = 0.004 and p = 0.007, respectively). No significant differences were observed in Ra, Rsk and Rku between enamel and dentin when using a high-speed electric handpiece or piezoelectric device. The turbine produced higher Ra and Rsk values on dentin than the other devices, while no significant differences were found between piezoelectric handpiece and high-speed electric contra-angle on both substrates. Summarizing, the findings of the present study demonstrated that turbine generated rougher surfaces on dentin compared to the other handpieces. Moreover, the turbine produced more asymmetrical surface profiles on both enamel and dentin. However, it should be considered that these differences in roughness (Ra) were within the range of 0.25–0.30 μm: it is still unclear if these variations, although statistically significant, will influence final clinical outcomes.
Severe dental erosion could be one of the complications of gastroesophageal reflux disease and food disorders such as bulimia nervosa. The aim of the present in vitro study was to evaluate the remineralization efficiency and the erosion prevention capability obtained by combining the use of Elmex Erosion Protection (Elm-EP) and GC Tooth Mousse (GC-TM) in cases of strongly eroded enamel surfaces. Twenty-four specimens of bovine tooth were superficially treated with hydrochloric acid to mimic severe erosion conditions. The specimens were divided into 3 groups accordingly to a different remineralizing treatment for 15 days: immersion in artificial remineralizing saliva, brushing with Elm-EP and brushing with Elm-EP in association with a daily application of GC-TM paste. After the remineralization procedures, the specimens were exposed to a treatment with acid. The effectiveness of the treatments were assessed by surface profilometric analysis and scanning electron microscopy at four different steps. Furthermore, the quantity of the Ca2+ lost during erosion was determined. The combined action of Elm-EP and GC-TM led to a 50% roughness decrease of critically eroded dental surfaces. The tandem use of Elmex Erosion Protection and GC Tooth Mousse resulted a promising protecting strategy for the prevention of the dental mineral loss.
This study compares the action of different handpieces (turbine, high-speed electric handpiece and piezoelectric device) on surface roughness of enamel and dentin when using diamond-coated working tips and burs of the same grit size. Experiment was conducted on 15 extracted first molars from patients aged 45 to 60 years. The occlusal portion was removed using a diamond-coated water wheel and then refined with a 120-130 μm grit bur in order to obtain a flat surface with an adequate exposition of the dentin core. Each surface was divided into three portions and every portion was finished with one of the three tested instruments. Rotary burs and piezoelectric tips had the same grit size (60 μm) and load on handpiece during preparation never exceeded 150 g. Surface roughness parameters (Ra, Rsk, Rku) were recorded with an optical profilometer and SEM analysis of treated surfaces and working tips was conducted. Ra and Rsk differed significantly between enamel and dentin only after using turbine (p=0.004 and p=0.007, respectively). No significant differences were observed in Ra, Rsk, and Rku between enamel and dentin when using high-speed electric handpiece or piezoelectric device. Turbine produced higher Ra and Rsk values on dentin than the other devices, while no significant differences were found between piezoelectric handpiece and high-speed electric contra-angle on both substrates. Summarizing, the findings of the present study demonstrated that turbine generated rougher surfaces on dentin compared to the other handpieces. Moreover, the turbine produced more asymmetrical surface profiles on both enamel and dentin. However, it should be considered that these differences in roughness (Ra) were within the range of 0.25-0.30 μm: it is still unclear if these variations, although statistically significant, will influence final clinical outcomes.