title: Warm vertical compaction sequences in relation to gutta-percha temperature.
abstract: The aim of this study was to analyze warm vertical compaction sequences in relation to the temperature variations of gutta-percha. Twenty-four maxillary incisors were obturated according to two different instrumentation techniques: Compaction and heating were performed with either the monomanual classical or bimanual method. To evaluate gutta-percha temperature, thermocouples (TC) were introduced into channels bored through the dentin into the root canal system or fixed on the root surface at 8 (TC8), 4 (TC4), 2 (TC2), and 0 mm (TC0) from the apex. Maximal temperature was 118 degrees C for TC8, 52 degrees C for TC4, and 44 degrees C for TC2 and TC0. At TC0, the temperature remained above 42.9 degrees C for 10 +/- 5 s. These results show the importance of heating down to a distance of 7 mm to ensure a significant increase in apical gutta-percha temperature. They further indicate that the last compaction should last more than 15 s to avoid detrimental cooling and dimensional variations. The principal differences between the monomanual and bimanual methods were the compaction time (5.07 +/- 0.2 min vs 4.02 +/- 0.3 min) and the number of compactions (8 +/- 1 vs 12 +/- 2).
authors.affiliation: Department of Endodontics, School of Dentistry, Universite Montpellier, France.
authors.forename: J Y
authors.initials: JY
authors.lastname: Blum
authors.forename: E
authors.initials: E
authors.lastname: Parahy
authors.forename: P
authors.initials: P
authors.lastname: Machtou
mesh_terms: D000704:Analysis of Variance; D001831:Body Temperature; D003786:Dental Pulp Cavity / Q000502:physiology; D004055:Differential Thermal Analysis; D005069:Evaluation Studies as Topic; D006171:Gutta-Percha / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D012389:Root Canal Obturation / Q000379:methods*; D013816:Thermodynamics; D019227:Tooth Apex / Q000502:physiology
chemical_list: D006171:Gutta-Percha