RESUMO
Objective To investigate the synergistic effect of calcium channel blocker on cyclosporine-induced gingival overgrowth (GO). Methods 130 renal transplant patients treated with cyclosporine were divided into group A (with calcium channel blocker) and group B (without calcium channel blocker). Demographic, pharmacologic and periodontal data were recorded. The prevalence and severity of GO were compared between the two groups. Three calcium channel blockers, including nifedipine, amlodipine and felodipine, were administered in the patients of group A. The relationships between these three calcium channel blockers and the prevalence of GO were analyzed. Results The patients receiving calcium channel blocker showed significantly higher prevalence of GO (44/73,60 % ) than those without calcium channel blocker (22/57, 39 %) (P＜0. 05). A higher proportion of mild GO (37 %) in group A was also observed than in group B (19 %, P＜0. 05). There were no significant differences in the proportions of moderate and/or severe GO between the two groups (P＞0. 05). Periodontal variables, including plaque index and papilla bleeding index, were significantly higher in GO patients than in those without GO in both two groups (P＜0. 05). In addition, the prevalence of GO in patients receiving nifedipine (77 %) was higher than in those receiving amlodipine (57 %) or felodipine (50 %). Conclusion The combination with calcium channel blocker is a risk factor of cyclosporine-induced GO and the use of nifedipine should be avoided for these at-risk patients.
RESUMO
OBJECTIVE: To evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste on shear bond strength and debonding failure modes of orthodontic brackets. MATERIALS AND METHODS: Freshly extracted premolars were randomly divided into four groups (n =18) as follows: in groups 1 and 3, the enamel was treated with a solution of CPP-ACP dissolved in artificial saliva; groups 2 and 4 served as controls, and the enamel was treated with artificial saliva. After conventional acid etching, in groups 1 and 2, brackets were bonded using a light-cured bonding system (Blugloo); while in groups 3 and 4, brackets were bonded using a conventional bonding system (Unite Bonding Adhesive). Bonded specimens were subjected to thermal cycling for 1000 cycles before debonding procedures. After debonding, teeth and brackets were examined under a stereomicroscope at 10x magnification to determine whether any adhesive remained, in accordance with the adhesive remnant index. The acid-etched enamel surfaces were also observed using scanning electron microscopy after treatment with and without CPP-ACP paste. RESULTS: The shear bond strengths of group 1 were significantly higher than those seen in group 2 (P < .01). There was no significant difference in the shear bond strengths of groups 3 and 4 (P > .05). Scanning electron microscopic observation showed that the pretreated enamel surface was rougher than that of the control surface after acid etching. CONCLUSION: The use of CPP-ACP can be considered as an alternative prophylactic application in orthodontic practice since it did not compromise bracket bond strength.
