IntroductionMicrobial infection plays an important role in the development of periapical (PA) lesions.1 Elimination of the pathological microflora of the root canal system is a major goal in endodontic treatment. Inadequate disinfection of the root canal system may lead to treatment failure and development of PA lesions.2 Killing the bacteria of root canal system is not always achievable with current root canal treatment (RCT) techniques (mechanical debridement associated with chemical irrigation).3,4 The anatomical complexity of the root canal system makes it almost impossible to completely eliminate the bacteria using conventional mechanical and chemical techniques, even with the highest technical standards.
5A 94% treatment success rate has been reported in cases with a negative culture before the obturation of root canal system. This rate decreases to 68% in cases undergoing root canal filling despite the cultures being positive. There is a challenge for the clinician in treatment of teeth with PA lesions, all efforts and attempts have been made to eliminate irritating agents from the root canal system in order to provide healing in the periradicular tissues. 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.
The aim of this study was to compare the effect of different modes of toothbrushing education (lecture, video and pamphlet) on the dental plaque index (PI) of adolescents. The cluster randomized intervention was performed on 128 participants aged 12 years, who were allocated into four groups based on the type of intervention. Group 1: no intervention; and groups 2, 3, 4: education via lecture, video, and pamphlet, respectively (n = 32). Their plaque index was measured at the baseline, 24 h and two months later. Data were analyzed by repeated measures analysis of variance (ANOVA), one-way ANOVA, independent and paired t-test. The plaque indices of groups 2, 3, 4 at 24 h (p values < 0.001) and two months (p values < 0.001) showed a significant reduction when compared to the baseline. The lowest PI score was observed in the pamphlet, video and lecture groups at 24 h, respectively. After 2 months, the lowest score of PI was measured in lecture, video and pamphlet groups, respectively; however, these differences were non-significant. Therefore, toothbrushing education via lecture, video and pamphlet reduced the dental plaque index with the same effectiveness.
Previous in vitro studies have suggested that simvastatin can be used as a direct pulp capping material due to its ability to induce odontoblastic differentiation and angiogenesis. The aim of this animal study was to evaluate the pulpal response to mineral trioxide aggregate (MTA) and four concentrations of simvastatin/MTA in combination. The study was conducted in two stages using four different simvastatin concentrations and MTA as a capping material for rat maxillary molars. The grades of inflammation and continuity of dentin formation were evaluated in hematoxylin and eosin (HE)-stained samples. Dentin thickness was determined by histomorphometric analysis, and the data were subjected to statistical analysis. On day 3, mild inflammation was observed in all groups. On day 7, the simvastatin groups showed a slightly higher rate of chronic inflammation. Inflammation was not present on day 30. Discontinuous dentin was present in all methylcellulose (control) samples. Continuous dentin was formed in all of the samples treated with 1.5% simvastatin. The greatest dentin thickness was observed after treatment with 1.5% simvastatin and MTA, followed by 0.5% simvastatin. Statistical analysis demonstrated no significant differences in dentin thickness and continuity between MTA and simvastatin at 0.5% and 1.5% (P > 0.05).
Owman-Moll 1996 {published data only} Owman-Moll P, Kurol J, Lundgren D. The e ects of a four-fold increased orthodontic force magnitude on tooth movement and root resorptions. An intra-individual study in adolescents.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.