PURPOSE: The aim of this study was to determine the effect of the acquired pellicle on enamel etching. MATERIALS AND METHODS: One-hundred teeth were sectioned in the buccal-lingual direction at the half crown. One-hundred half-crowns were polished with pumice powder and rotating brushes (group B) and one-hundred half-crowns were not polished on the buccal surface (group A). The samples were etched by 37% orthophosphoric acid gel for 30 seconds in a 2 mm diameter circular area at the middle upper section of the crown, rinsed with distilled water for 20 s, air dried for 20 s and observed by Scanning Electron Microscopy. Three independent operators determined the quality of enamel etching on a four-point scale using 200 images, which were computed by digital Image Analysis software. It analyses the grey values and converts them to three-dimensional graphics to value the surface extension. Analysis Of Variance test was used for comparisons between and within groups. RESULTS: The mean of the operator values for the A samples is 2 ("Poorly defined etch") and for the B samples is 3 ("Defined etch"). The Image Analysis showed a significant difference (Analysis of Variance test) in the extension of the etched areas between groups A and B. The samples from group B had 11.7% more effectively etched enamel surfaces than the samples from group A. CONCLUSION: Acquired pellicle removal by dental prophylaxis is necessary before enamel etching because it improves the effectiveness of the etching procedure.
The Morphological Effect of the Acquired Pellicle on Acid-etched Enamel: A Scanning Electron Microscopy Analysis
ERAMO, Stefano;LOMURNO, Giuseppe
2014
Abstract
PURPOSE: The aim of this study was to determine the effect of the acquired pellicle on enamel etching. MATERIALS AND METHODS: One-hundred teeth were sectioned in the buccal-lingual direction at the half crown. One-hundred half-crowns were polished with pumice powder and rotating brushes (group B) and one-hundred half-crowns were not polished on the buccal surface (group A). The samples were etched by 37% orthophosphoric acid gel for 30 seconds in a 2 mm diameter circular area at the middle upper section of the crown, rinsed with distilled water for 20 s, air dried for 20 s and observed by Scanning Electron Microscopy. Three independent operators determined the quality of enamel etching on a four-point scale using 200 images, which were computed by digital Image Analysis software. It analyses the grey values and converts them to three-dimensional graphics to value the surface extension. Analysis Of Variance test was used for comparisons between and within groups. RESULTS: The mean of the operator values for the A samples is 2 ("Poorly defined etch") and for the B samples is 3 ("Defined etch"). The Image Analysis showed a significant difference (Analysis of Variance test) in the extension of the etched areas between groups A and B. The samples from group B had 11.7% more effectively etched enamel surfaces than the samples from group A. CONCLUSION: Acquired pellicle removal by dental prophylaxis is necessary before enamel etching because it improves the effectiveness of the etching procedure.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
