ABSTRACT
Introduction: Elimination of pathological microflora of root canal systems is a major goal in endodontic treatment. This study aimed to compare the antimicrobial efficacy of calcium hydroxide as an intracanal medication and antibacterial photodynamic therapy [aPDT] against Enterococcus faecalis and Candida albicans in teeth with periapical [PA] lesions
Methods: This in vivo study was conducted on 20 patients with single-rooted mandibular premolar with previously failed endodontic treatment. This study was performed as a clinical trial [IRCTID: IRCT2016090429686N1]. After conventional chemo-mechanical root canal preparation [hand and rotary instruments and 2.5% NaOCl], microbiological samples were obtained using sterile paper points, then stored in thioglycolate solution and transferred to a microbiology laboratory. Group 1 [n = 10] specimens underwent aPDT [diode laser 808 nm + 50 mg/mL methylene blue], while creamy calcium hydroxide paste was used in group 2 for a duration of 1 week. A control sample was taken with sterile paper points and F3 Protaper rotary file. The samples were dispersed in transport medium, serially diluted, and cultured on selective mediums to determine the number of colony forming units [CFUs]. Data were analyzed by Mann-Whitney U test at 5% significance level. The significance level for all analyses was set at P < 0.05
Results: Number of CFU significantly decreased in both groups after the interventions [P < 0.001]; however, there was no significant difference in the colony count between the 2 groups
Conclusion: aPDT and calcium hydroxide therapy showed the same antimicrobial efficacy on E. faecalis and C. albicans
ABSTRACT
Objective: This study aimed to assess the destructive effects of citric acid, lactic acid and acetic acid produced from the fermentation of foods on primary teeth enamel
Methods: This in vitro, experimental study was conducted on 24 sound primary teeth. The teeth were polished with a fine abrasive paper under running water. Tooth pieces measuring 3×4×3mm were cut out of the teeth and stored in 100% humidity until the experiment. The specimens were divided into 3 groups [n=8] and immersed in acetic acid, citric acid and lactic acid, respectively. The enamel microhardness of specimens was measured by Vickers microhardness tester at baseline and 5 and 30min after immersion in the freshly prepared acid solutions
Results: Repeated measures ANOVA showed that the effect of immersion time on microhardness was significant [p<0.001]. Pairwise comparison among 0, 5 and 30 minutes time points using Bonferroni adjustment showed significant differences in microhardness at different time points [p<0.001]. Evaluation of the effect of type of acid on microhardness revealed that the microhardness was not significantly different in the three groups of acids [p=0.915]. Among the three understudy acids, only the reduction in microhardness from time 0 to 30 minutes was significantly different between lactic acid and acetic acid [p=0.042]
Conclusion: Citric acid, lactic acid and acetic acid were all capable of demineralization and reduction of enamel microhardness. A significant difference existed in the demineralization potential of acids [the highest for lactic acid]. However, this effect was more significant early after exposure