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Purpose: The goal of this in vitro study was to identify the topographical features of the enamel surface deproteinized and etched with phosphoric acid (H3PO4) compared to phosphoric acid alone. Materials and method: Ten extracted lower first and second permanent molars were polished with pumice and water, and then divided into 4 equal buccal sections having similar physical and chemical properties. The enamel surfaces of each group were subjected to the following treatments: Group A: Acid Etching with H3PO4 37% for 15 seconds. Group AH1: Sodium Hypochlorite (NaOCl) 5.25% for 30 seconds followed by Acid Etching with H3PO4 37% for 15 seconds. Group AH2 ; Sodium Hypochlorite (NaOCl) 5.25% for 60 seconds followed by Acid Etching with H3PO4 37% for 15 seconds. Results showed that group AH2 etching technique reached an area of 76.6 mm2 of the total surface, with a 71.8 mm2 (94.47%), type 1 and 2 etching pattern, followed by group AH1 with 55.9 mm2 out of 75.12 mm2 (74.1%), and finally group A with only 36.8 mm2 (48.83%) out of an area of 72.7 mm2. A significant statistical difference (P <0 .05) existed between all groups, leading to the conclusion that enamel deproteinization with 5.25% NaOCl for 1 minute before H3PO4, etching increases the enamel conditioning surface as well as the quality of the etching pattern.

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The purpose of this study was to determine the sagittal response of Class III patients in the primary, mixed, and late mixed dentition phases fitted with a protraction mask and expansion. The before-and-after cephalometric records of 112 patients divided by gender were analyzed at age groups 3 to 6, 6 to 9, and 9 to 12 years to assess the maxillary, mandibular, and intermaxillary sagittal changes. Data were correlated by means of paired t tests and Scheff¿e multiple contrasts. The study showed: (1) descriptive statistics and the before-and-after results in males and females in the different age groups; (2) the changes in males and females, disregarding age; and (3) the changes at the different ages, disregarding gender. Results show no significant differences between males and females in most of the angular and linear measurements at different ages. Greater significant changes were seen in patients treated in the primary and mixed dentition phases. Females showed highly significant changes in most linear and angular measurements between the ages of 3 and 6 years (P <.0001) compared with males (P <.05 ) at the same age. Significant changes were seen in the angle between the anterior part of the maxilla and the base of the skull (SNA), the maxillary depth, and the facial convexity angles, being more active in females than males. In contrast, the angle between the anterior part of the mandible and the base of the skull (SNB) showed no significant changes in all age groups, with the exception of males between 3 and 6 years. Even if correction can be achieved in all age groups, we recommend that treatment be started as soon as the diagnosis is made and cooperation allows for it. Young patients show greater and faster results in less time. Esthetics are greatly enhanced, compliance is improved, and the possible psycho-social scars can be greatly reduced.

Purpose: The goal of this in vitro study was to identify the topographical features of deproteinized (NaOCl)and etched with phosphoric acid (H3PO4) enamel surface, compared to phosphoric acid surface alone with a Resin Replica model. Materials: Ten extracted lower first and second permanent molars were polished with pumice and water, and then divided into 3 equal buccal sections having similar physical and chemical properties. The enamel surfaces of each group were subjected to the following treatments: Group A: Acid Etching with H3PO4 37% for 15 seconds. Group B: Sodium Hypochlorite (NaOCl) 5.25% for 60 seconds followed by Acid Etching with H3PO4 37% for 15 seconds. Group C; No treatment (control). All the samples were treated as follow: Adhesive and resin were applied to all groups after A, B and C treatment were performed; Then enamel/dentin decalcification and deproteinization and topographic SEM Resin Replica assessment were used to identify resin tags enamel surface quality penetration. Results showed that group B reached an area of 7.52mm2 of the total surface, with a 5.68 mm2 (73%)resin tag penetration equivalent type I and II etching pattern, 1.71 mm2 (26%) equivalent to type III etching pattern and 0.07 mm2 (1%)unaffected surface. Followed by group A with 7.48 mm2 of the total surface, with a 3.47 mm2 (46 %)resin tag penetration equivalent to type I and II etching pattern, 3.30 mm2 (45 %)equivalent to type III etching pattern and 0.71 mm2, and (9 %) unaffected surface. Group C did not show any resin tag penetration. A significant statistical difference (P &lt;0,001) existed between groups A and B in resin quality penetration, leading to the conclusion that when the enamel is deproteinizated with 5.25% NaOCl for 1 minute prior H3PO4,the surface and topographical features of the replica resin penetration surface increases significantly with type I-II etching pattern.