P S Viana1,2, M O Orlandi3, A C Pavarina1, A L Machado1, C E Vergani4. 1. Department of Dental Materials and Prosthodontics, Araraquara Dental School, Faculdade de Odontologia de Araraquara, UNESP, Univ Estadual Paulista, Rua Humaitá, N° 1680, Araraquara, SP, CEP:14801-903, Brazil. 2. Faculdade de Odontologia, Universidade Santo Amaro, UNISA, São Paulo, Brazil. 3. Department of Physical Chemistry, Institute of Chemistry, UNESP, Univ Estadual Paulista, Araraquara, Brazil. 4. Department of Dental Materials and Prosthodontics, Araraquara Dental School, Faculdade de Odontologia de Araraquara, UNESP, Univ Estadual Paulista, Rua Humaitá, N° 1680, Araraquara, SP, CEP:14801-903, Brazil. vergani@foar.unesp.br.
Abstract
OBJECTIVES: The morphology and chemical composition of enamel submitted to different sterilization methods was studied. METHODS: X-ray photoelectron spectroscopy (XPS), field emission gun scanning electron microscopy (FEG-SEM), and energy-dispersive X-ray spectroscopy (EDS) were performed to evaluate 50 bovine enamel specimens sterilized using four methods: microwaving (MI), gamma irradiation (GI), ethylene oxide (EO), and steam autoclave (SA). Non-sterilized specimens were used as control. RESULTS: XPS indicated that the concentration of P (phosphorus), CO3 (carbonate), and CO3/P was not changed in all groups. GI produced no significant change on elemental composition. SA produced the major decrease in calcium (Ca), Ca/P ratio, and increase in N (nitrogen). MI was found to decrease Ca, Ca/P ratio and O (oxygen), and increase in C (carbon) and N. EO produced decrease in Ca and O with increased C concentration. FEG-SEM revealed surface and in-depth morphological changes on SA specimens. Minor surface alterations were observed for EO and for MI groups, and no alteration was observed on GI group. EDS indicated no difference on elemental composition of enamel bulk among groups. CONCLUSIONS: SA produced mineral loss and morphological alterations on surface and in depth. MI and EO sterilization caused mineral loss showing only slight alteration on enamel surface. GI sterilization preserves the morphological characteristics of enamel. The sterilization methods could be classified from lower to high damage as GI < MI < EO < SA. CLINICAL RELEVANCE: This is a comprehensive comparative study where different methods for enamel sterilization were investigated in terms of chemical changes. The results presented here may help researchers to choose the most appropriate method for their research setting and purpose.
OBJECTIVES: The morphology and chemical composition of enamel submitted to different sterilization methods was studied. METHODS: X-ray photoelectron spectroscopy (XPS), field emission gun scanning electron microscopy (FEG-SEM), and energy-dispersive X-ray spectroscopy (EDS) were performed to evaluate 50 bovine enamel specimens sterilized using four methods: microwaving (MI), gamma irradiation (GI), ethylene oxide (EO), and steam autoclave (SA). Non-sterilized specimens were used as control. RESULTS: XPS indicated that the concentration of P (phosphorus), CO3 (carbonate), and CO3/P was not changed in all groups. GI produced no significant change on elemental composition. SA produced the major decrease in calcium (Ca), Ca/P ratio, and increase in N (nitrogen). MI was found to decrease Ca, Ca/P ratio and O (oxygen), and increase in C (carbon) and N. EO produced decrease in Ca and O with increased C concentration. FEG-SEM revealed surface and in-depth morphological changes on SA specimens. Minor surface alterations were observed for EO and for MI groups, and no alteration was observed on GI group. EDS indicated no difference on elemental composition of enamel bulk among groups. CONCLUSIONS:SA produced mineral loss and morphological alterations on surface and in depth. MI and EO sterilization caused mineral loss showing only slight alteration on enamel surface. GI sterilization preserves the morphological characteristics of enamel. The sterilization methods could be classified from lower to high damage as GI < MI < EO < SA. CLINICAL RELEVANCE: This is a comprehensive comparative study where different methods for enamel sterilization were investigated in terms of chemical changes. The results presented here may help researchers to choose the most appropriate method for their research setting and purpose.
Entities:
Keywords:
Chemical analysis; Dental enamel; EDS; SEM; Sterilization; XPS
Authors: Rodrigo O A Souza; Geraldo H L Lombardo; Sarina M B Pereira; Sandra C Zamboni; Marcia C Valera; Maria A M Araujo; Mutlu Ozcan Journal: Int J Prosthodont Date: 2010 Jan-Feb Impact factor: 1.681
Authors: Maria Angélica Hueb De Menezes Oliveira; Carolina Paes Torres; Jaciara Miranda Gomes-Silva; Michelle Alexandra Chinelatti; Fernando Carlos Hueb De Menezes; Regina Guenka Palma-Dibb; Maria Cristina Borsatto Journal: Microsc Res Tech Date: 2010-05 Impact factor: 2.769