[Polymerization exothermal reaction of dental prosthetic resin for temporary crowns. A comparative evaluation].
BACKGROUND
The aim of the present study is to evaluate the risk of a possible thermal stress of the pulpal tissue during the fabrication of a temporary crown when using the direct technique.


METHODS
For this study, 7 different brands of acrylic resin including Acrylic type and Bis-Gma type have been tested. At this purpose one series of in vitro experimental trials were performed. The trials have evaluated the temperature increase inside the pulp chamber of an extracted tooth during the fabrication of a provisional crown. The temperatures reached by the resins tested were measured using a digital thermometer connected with a thermal probe.


RESULTS
The temperatures measured during the experimental trials show a different ability by the 7 tested resins to produce heat. Indeed, while the polymethylmethacrylate resins show higher increments rate of temperature, the Bis-Gma resins produce less dramatic increase along with lower temperatures peaks.


CONCLUSIONS
Testing the 7 different resins has proved that there is an actual risk to cause lesions to the pulpal tissue during the placement of a provisional crown when using the direct technique. The materials which show a reduced exothermal reaction are: IsoTemp and Protemp II.
Barlattani
A
A
S. Giovanni Calibita-Fatebenefratelli, Isola Tiberina, Roma, Cattedra di Protesi, Corso di Laurea in Odontoiatria e Protesi dentaria, Facoltà di Medicina e Chirurgia, Università degli Studi Tor Vergata, Rome, Italy.
Cardelli
P
P
Cioccolanti
F
F
Gallio
M
M
D003442:Crowns; D006358:Hot Temperature; D011108:Polymers; D012117:Resins, Synthetic / Q000737:chemistry*; D013997:Time Factors
D011108:Polymers; D012117:Resins, Synthetic