Danilo Mathias Zanello Guerisoli

Effect of different bleaching systems on the ultrastructure of bovine dentin

The aim of this study was to evaluate in vitro the effect of different in-office bleaching systems on the surface morphology of bovine dentin. Thirty tooth fragments measuring 4 x 4mm, containing enamel and dentin, were obtained from the crowns of extracted bovine incisors. Samples were subjected to simulated intracoronal bleaching techniques using conventional (Opalescence Endo and Whiteness Super Endo) and light-activated systems (Opalescence Xtra) and Whiteness HP Maxx). Controls were treated with either sodium perborate mixed with 10% hydrogen peroxide or no bleaching agent. The samples were observed under SEM and the recorded images were evaluated for topographic alterations. The ultrastructural alterations of dentin observed in this study varied greatly between groups according to the products used. Higher pH products (Whiteness HP Maxx) and Opalescence Xtra) associated with in-office techniques yielded better maintenance of dentin ultrastructure. Apparently, both low pH and hydrogen peroxide oxidation play a role in altering the ultrastructure of dentin during internal dental bleaching. The use of alkaline products with reduced time of application (in-office techniques) may decrease such morphological alterations.

Evaluation of the temperature of different refrigerant sprays used as a pulpal test

The temperature of different refrigerant sprays (Endo-Ice, Endo-Frost, Coolermatic and Sprayon Contact and Tuner Cleaner) used as pulpal tests were evaluated in vitro. A thermocouple placed inside the pulp chamber of a maxillary central incisor was used to register the temperature changes when the refrigerant sprays were applied with a cotton swab, for 10 s. Results indicate that Endo-Ice and Endo-Frost presented the lowest temperatures among the refrigerant sprays tested. Temperatures measured inside the pulp chamber, however, were statistically similar in all groups.

Dor Pós Operatória em Dentes com Infecções após Única ou Múltiplas Sessões - Revisão Sistemática

Objetivo: Verificar a presenca de dor pos-operatoria em dentes com infeccoes que receberam a terapia endodontica em sessao unica (apos obturacao) e multiplas sessoes (apos uso de medicacao intracanal), atraves de revisao sistematica. Metodo: Realizou-se pesquisa em fonte de catalogacao bibliografica identificada eletronicamente por MEDLINE, entre 1966 a 20 de fevereiro de 2011. Como estrategia de busca foram utilizados os termos com a expressao and: single visit root canal treatment, single visit root canal therapy, multiple visit root canal treatment, multiple visit root canal therapy, single visit root canal treatment postoperative pain, single visit root canal therapy postoperative pain, multiple visit root canal treatment postoperative pain, multiple visit root canal therapy postoperative pain, Calcium Hydroxide intracanal medicament, Calcium Hydroxide intracanal medicament postoperavite pain. Resultados: Foram encontrados 278 artigos. Para selecao, criterios de inclusao foram estabelecidos em duas etapas, na primeira 15 trabalhos foram selecionados. Na segunda, como criterio de inclusao, trabalhos que continham a avaliacao da dor em polpas vivas e necrosadas e que nao avaliaram a dor, somente apos a obturacao em sessao unica, e apos a medicacao intracanal, em sessoes multiplas foram descartados. Do total encontrado, 2 artigos atenderam aos criterios de inclusao. Conclusoes: Baseado na analise dos trabalhos selecionados a partir dos criterios de inclusao deste estudo, dentes que receberam a medicacao intracanal, a qual foi o hidroxido de calcio, apresentaram menor intensidade de dor pos operatoria, tratamentos de dentes sintomaticos (dor previa) revelaram os maiores indices de desconforto pos-operatorio independente de sessao unica ou multipla.(AU) Objective: To verify the presence of postoperative pain in teeth with infections who received endodontic therapy in one session (after filling) and multiple sessions (after intracanal medication), through a systematic review. Methods: A research was conducted in the MEDLINE full-text electronic database between 1966 and February 20, 2011. The following key words were used with the expression and to narrow the search: single visit root canal treatment, single visit root canal therapy, multiple visit root canal treatment, multiple visit root canal therapy, single visit root canal treatment postoperative pain, single visit root canal therapy postoperative pain, multiple visit root canal treatment postoperative pain, multiple visit root canal therapy postoperative pain, Calcium Hydroxide intracanal medicament, Calcium Hydroxide intracanal medicament postoperative pain. Results: The search retrieved 278 articles, of which 28 were literature reviews, 15 case reports, 16 meta-analyses and systematic reviews. Among the other studies, 33 were in vitro, 10 were in animals, 6 were retrospective and 5 were in primary teeth. Regarding the number of sessions, 47 articles were found, including 12 on intracanal medication, 14 on systemic medication and 6 flare-ups. Papers without an abstract were 36 and 50 were classified as other (rehabilitation, fractures, incomplete apex formation, etc.). Out of the total of papers retrieved, only two met the inclusion criteria. Conclusions: Teeth that received calcium hydroxide intracanal medication showed lower intensity of postoperative pain, treatment of symptomatic teeth (previous pain) showed the highest rates of postoperative discomfort regardless if treated in single or multiple sessions.(AU)