The laboratory dental cutting rates in comparison with the clinical dental cutting rates and the cutting rates on a new suggested training block

الملخص EN

Background : Preclinical cavity preparation performed in the laboratory on different types of typodont mannequin teeth that keep changing in chemistry and properties by the manufacturer, while clinical cavity preparation performed on natural teeth of well known chemistry and properties without a transitional format, the aim of this study was to compare the laboratory dental cutting rates with the clinical dental cutting rates and the cutting rates on a new suggested transitional training block Materials and methods : the cutting rates were evaluated on 30 artificial teeth and 30 natural teeth the roots were sectioned and the crowns were embedded in acrylic blocks (25x25x15 mm) exposing the flat labial surface, the specimens were divided according to the cutting equipment and the type of the exposed labial surfaces into : Group 1 : the previous laboratory dental cutting (10 original Frasaco / Nissin dental product) Group 2 : the current laboratory dental cutting (10 Frasaco Dent Iran) Group 3 : dental cutting on anew suggested training block (10 denture teeth –Pigeon teeth China) Group 4 : low speed clinical dental cutting (10 dentin specimens) The cutting was performed in all the above groups with stainless steel fissure bur and low speed hand piece Group 5 : high speed clinical dental cutting on dentin (10 dentin specimens) The cutting was performed with carbide fissure bur and turbine Group 6 : high speed clinical dental cutting on enamel (10 enamel specimens) The cutting was performed with diamond fissure bur and turbine. The cutting rates (mm / sec)were recorded and statistically analyzed using ANOVA test and t-test Results : the results showed there was no significant difference between group 3and the mean of the clinical dental cutting (group 4, 5 and 6), a significant differences were presented between group 1Vs group 3 and between group 1 Vs the mean of the clinical dental cutting(group 4,5 and 6), while group 2 showed a highly significant difference Vs group 1 and a very highly significance difference Vs group 3 and the mean of the clinical dental cutting(group 4,5 and 6) Conclusion : The previous laboratory dental cutting was much closer to the clinical dental cutting (slightly slower) While the current laboratory dental cutting far away (too fast) from the clinical dental cutting.

Furthermore the dental cutting on the new suggested training block comparable to the clinical dental cutting.