Ronauk Singh1, Arvind Tripathi2, R K Dhiman3, Dinesh Kumar3. 1. Dental Officer (Prosthodontics), 33 Corps Dental Unit, C/o 99 APO, India. 2. Professor & Head, Dept of Prosthodontics, Saraswati Dental College, Lucknow, India. 3. Associate Professor, Dept of Dental Surgery, Armed Forces Medical College, Pune 40, India.
Abstract
BACKGROUND: Resin materials used in the fabrication of direct provisional restoration exhibit an exothermic reaction and the extent of damage may also depend on the remaining dentine thickness. An ex-vivo study was envisaged to compare the time related temperature changes in the pulp chamber during the fabrication of fixed partial denture provisional restorations using direct technique. The effect of differently prepared teeth (with varying remaining dentine thickness) on the above mentioned temperature changes were also evaluated. METHODS: Thermal changes were calculated in pulp chamber of three differently prepared tooth having different amount of remaining dentinal thickness (45 samples) and control with no tooth media (15 samples), using three different types of autopolymerizing provisional restorative materials using Cr/Al thermocouple connected to digital thermometer. RESULTS: The data for the mean peak temperature rise was subjected to one way ANOVA analysis for relative comparison among subgroups within each main group and across the main groups. The results showed a statistically significant difference across both the subgroups and the main groups (p < 0.001). Then Turkey HSD test was applied to determine the significance of statistical difference between the means, within the groups. The differences in temperature rise were statistically significant for the three resins (p < 0.001). CONCLUSION: Polymethylmethacrylate (DPI) showed the highest temperature rise value followed by polyethyl methacrylate (Tempron) and Bis-acrylate composite (CoolTemp). The maximum temperature rise was found on molar full veneer preparation followed by molar three quarter preparation and premolar three quarter preparation. Data and results from current study may assist clinicians to select an autopolymerizing provisional restorative resin when employing direct technique of fabricating provisional restorations for a specific tooth preparation which would cause minimal thermal trauma to pulpal tissue.
BACKGROUND: Resin materials used in the fabrication of direct provisional restoration exhibit an exothermic reaction and the extent of damage may also depend on the remaining dentine thickness. An ex-vivo study was envisaged to compare the time related temperature changes in the pulp chamber during the fabrication of fixed partial denture provisional restorations using direct technique. The effect of differently prepared teeth (with varying remaining dentine thickness) on the above mentioned temperature changes were also evaluated. METHODS: Thermal changes were calculated in pulp chamber of three differently prepared tooth having different amount of remaining dentinal thickness (45 samples) and control with no tooth media (15 samples), using three different types of autopolymerizing provisional restorative materials using Cr/Al thermocouple connected to digital thermometer. RESULTS: The data for the mean peak temperature rise was subjected to one way ANOVA analysis for relative comparison among subgroups within each main group and across the main groups. The results showed a statistically significant difference across both the subgroups and the main groups (p < 0.001). Then Turkey HSD test was applied to determine the significance of statistical difference between the means, within the groups. The differences in temperature rise were statistically significant for the three resins (p < 0.001). CONCLUSION:Polymethylmethacrylate (DPI) showed the highest temperature rise value followed by polyethyl methacrylate (Tempron) and Bis-acrylate composite (CoolTemp). The maximum temperature rise was found on molar full veneer preparation followed by molar three quarter preparation and premolar three quarter preparation. Data and results from current study may assist clinicians to select an autopolymerizing provisional restorative resin when employing direct technique of fabricating provisional restorations for a specific tooth preparation which would cause minimal thermal trauma to pulpal tissue.