RESUMO
The initial characteristics of white spot lesion (WSLs), such as the degree of integrated mineral loss (ΔZ), depth and pattern of mineral distribution, have an impact on further demineralization and remineralization. However, these lesion parameters have not been evaluated in WSLs produced from microcosm biofilms. OBJECTIVE: This study characterized artificial white spot lesions produced on human enamel under microcosm biofilm for different experimental periods. METHODOLOGY: In total, 100 human enamel specimens (4x4mm) were assigned to 5 distinct groups (n=20/group) differing according to the period of biofilm formation (2, 4, 6, 8 or 10 days). Microcosm biofilm was produced on the specimens from a mixture of human and McBain saliva at the first 8h. Enamel samples were then exposed to McBain saliva containing 0.2% sucrose. WSLs formed were characterized by quantitative light-induced fluorescence (QLF) and transverse microradiography (TMR). Data were analyzed by ANOVA/Tukey or Kruskal-Wallis/Dunn tests (p<0.05). RESULTS: A clear time-response pattern was observed for both analyses, but TMR was able to better discriminate among the lesions. Regarding QLF analysis, median (95%CI; %) changes in fluorescence ∆Z were -7.74(-7.74:-6.45)a, -8.52(-8.75:-8.00)ab, -9.17(-10.00:-8.71)bc, -9.58(-10.53:-8.99)bc and -10.01(-11.44:-9.72)c for 2, 4, 6, 8, and 10 days, respectively. For TMR, median (95%CI; vol%.µm) ∆Z were 1410(1299-1479)a, 2420(2327-2604)ab, 2775(2573-2899)bc, 3305(3192-3406)cd and 4330(3972-4465)d, whereas mean (SD; µm) lesion depth were 53.7(12.3)a, 71.4(12.0)a, 103.8(24.8)b, 130.5(27.2)bc, 167.2(39.3)c for 2, 4, 6, 8 and 10 days, respectively. CONCLUSION: The progression of WSLs formed on human enamel under microcosm biofilm can be characterized over 2-10 days, both by QLF and TMR analyses, although the latter provides better discrimination among the lesions.
Assuntos
Cárie Dentária , Desmineralização do Dente , Biofilmes , Esmalte Dentário , Humanos , Microrradiografia , Saliva , Remineralização DentáriaRESUMO
Abstract The initial characteristics of white spot lesion (WSLs), such as the degree of integrated mineral loss (ΔZ), depth and pattern of mineral distribution, have an impact on further demineralization and remineralization. However, these lesion parameters have not been evaluated in WSLs produced from microcosm biofilms. Objective: This study characterized artificial white spot lesions produced on human enamel under microcosm biofilm for different experimental periods. Methodology: In total, 100 human enamel specimens (4x4mm) were assigned to 5 distinct groups (n=20/group) differing according to the period of biofilm formation (2, 4, 6, 8 or 10 days). Microcosm biofilm was produced on the specimens from a mixture of human and McBain saliva at the first 8h. Enamel samples were then exposed to McBain saliva containing 0.2% sucrose. WSLs formed were characterized by quantitative light-induced fluorescence (QLF) and transverse microradiography (TMR). Data were analyzed by ANOVA/Tukey or Kruskal-Wallis/Dunn tests (p<0.05). Results: A clear time-response pattern was observed for both analyses, but TMR was able to better discriminate among the lesions. Regarding QLF analysis, median (95%CI; %) changes in fluorescence ∆Z were -7.74(-7.74:-6.45)a, -8.52(-8.75:-8.00)ab, -9.17(-10.00:-8.71)bc, -9.58(-10.53:-8.99)bc and -10.01(-11.44:-9.72)c for 2, 4, 6, 8, and 10 days, respectively. For TMR, median (95%CI; vol%.µm) ∆Z were 1410(1299-1479)a, 2420(2327-2604)ab, 2775(2573-2899)bc, 3305(3192-3406)cd and 4330(3972-4465)d, whereas mean (SD; µm) lesion depth were 53.7(12.3)a, 71.4(12.0)a, 103.8(24.8)b, 130.5(27.2)bc, 167.2(39.3)c for 2, 4, 6, 8 and 10 days, respectively. Conclusion: The progression of WSLs formed on human enamel under microcosm biofilm can be characterized over 2-10 days, both by QLF and TMR analyses, although the latter provides better discrimination among the lesions.
RESUMO
PURPOSE: To evaluate the clinical efficacy of two commercially available, fluoride-free, alcohol-free mouthwashes containing either 0.075% or 0.07% cetylpyridinium chloride (CPC) in controlling established dental plaque and gingivitis compared to a non-antibacterial control mouthwash. METHODS: A 6-week double-blind, randomized clinical trial was conducted in Trujillo Alto, Puerto Rico. Recruited subjects were randomly assigned to one of three treatment groups: (1) a fluoride-free, alcohol-free mouthwash containing 0.075% CPC (TG); (2) a fluoride-free, alcohol-free mouthwash containing 0.07% CPC (PC); and (3) a fluoride-free, alcohol-free mouthwash without antibacterial agent (NC). Subjects were instructed to rinse with the assigned mouthwash, after tooth brushing, twice daily (morning and evening). After 4 and 6 weeks of product use, subjects were examined for gingivitis (Whole Mouth Gingival, Gingival Interproximal, Gingival Severity Indexes) and plaque (Whole Mouth Plaque, Plaque Interproximal, and Plaque Severity Indexes) parameters. ANCOVA and post hoc Tukey's pair-wise comparisons (α = 0.05) were performed for treatment group comparisons. RESULTS: A total of 132 subjects were screened; 120 were enrolled; and 116 completed the study. After 6 weeks of product use, participants who rinsed with the CPC-containing mouthwashes exhibited statistically significant (P < 0.05) reductions in all the gingivitis and plaque parameters evaluated, whereas in those using the non-antibacterial mouthwash, significant reductions were only observed in whole mouth and interproximal plaque scores. No statistically significant (P > 0.05) differences were observed, with respect to the gingival and plaque parameters, between the two CPC-containing mouthwashes.