ABSTRACT
The aim of this study was to evaluate and compare the in vitro effect of the Erbium-Doped Yttrium Aluminum Garnet [Er:YAG] laser with different radiation distances and high-speed rotary treatment on the shear bond strength of flowable composite to enamel of human permanent posterior teeth. Freshly extracted human molar teeth with no caries or other surface defects were used in this study [n=45]. The teeth were randomly divided into 3 groups. Group 1: treated with non-contact Er:YAG Laser and etched with Er:YAG laser, Group 2: treated with contact Er:YAG Laser and etched with Er:YAG laser, Group 3 [control]: treated with diamond fissure bur and etched with acid phosphoric 37%. Then the adhesive was applied on the rtemisi of the teeth and polymerized using a curing light appliance. Resin cylinders were fabricated from flowable composite. Shear bond strength was tested at a crosshead speed of 0.5 mm/min. The amount of Shear Bond Strength [SBS] in the 3 treatment groups was not the same [P<0.05] .The group in which enamel surfaces were treated with diamond fissure bur and etched with acid [rtemis group] had the highest mean shear bond strength [19.92 +/- 4.76] and the group in which the enamel surfaces were treated with contact Er:YAG laser and etched with Er:YAG laser had the lowest mean shear bond strength [10.89 +/- 2.89]. Mann-whitney test with adjusted P-value detected significant difference in shear bond strength between the control group and the other 2 groups [P < 0.05]. It was concluded that both contact and non-contact Er:YAG laser treatment reduced shear bond strength of flowable resin composite to enamel in comparison with conventional treatment with high speed rotary. Different Er:YAG laser distance irradiations did not influence the shear bond strength of flowable composite to enamel
ABSTRACT
Primary antibody deficiencies [PAD] are a group of immune system disorders, associated with decreased levels of secretory and protective immunoglobulins. Because of the important role of immunoglobulins in the protection of oral cavity, patients with PADs are more susceptible to dental caries or oral manifestations. This study was performed to investigate the oral and dental manifestations of PADs patients. In this study, 33 patients with PADs [21 common variable immunodeficiency, 8 X-linked agammaglobulinemia and 4 hyper IgM syndrome] and 66 controls were examined; the number of decayed, missed and filled teeth [DMFT] were investigated. Aphthous was the most frequent manifestation in PADs patients [38.7%], which was significantly 16.7% higher than the controls [p=0.03]. The patients with PADs showed significantly higher presentation of other oral and dental manifestations, including herpes sores, candidiasis tonsillitis, gingivitis, calculus, enamel hypoplasia and other ulcerations. The mean DMFT scores were 6.15 +/- 3.6 and 1.93 +/- 0.4 in PADs patients and controls, respectively [p<0.001]. Although the patients with common variable immunodeficiency had higher means of DMFT in comparison with other groups of PADs, this difference was not statistically significant. This study showed significantly higher frequency of oral and dental manifestations in the patients with PADs compared to controls. Therefore, regular examination of oral cavity could be suggested in this group of immunodeficient patients