Comparison of the antimicrobial efficacy of calcium hydroxide and photodynamic therapy against enterococcus faecalis and candida albicans in teeth with periapical lesions; an in vivo study

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

In-vitro comparison of the antimicrobial properties of glass ionomer cements with zinc phosphate cements

White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. Long-lasting antibacterial properties of orthodontic cements can reduce this phenomenon. The aim of this research was to compare antimicrobial activity of three commercial glass ionomer cements with three commercial zinc phosphate cements, over time, against streptococcus mutans and candida albicans. Direct contact test [DCT] was used to evaluate the antibacterial and antifungal activity of products after 48 h and 7 days of incubation. The results demonstrated that all the cements presented antibacterial activity but the antibacterial activity of glass ionomer cements was more than that of zinc phosphate cements. Counts of C. albicans after 48 h were lower and statistically different in the GIC group in relation to the control groups. But no differences were observed between GIC and control groups at 7 days. Based on the results of this study, the antimicrobial and mainly antifungal effects of all the cements were so short