Comparative evaluation of postoperative pain following chemomechanical preparation of single-rooted nonvital teeth with symptomatic apical periodontitis with and without laser irradiation: A double-blind randomized placebo controlled clinical trial.

Background: Postoperative pain can occur because of residual infection even after effective chemomechanical preparation. This study aimed to compare postoperative pain after chemomechanical preparation with placebo and laser irradiation in nonvital teeth having symptomatic apical periodontitis. Materials and Methods: Sixty (n = 30) participants after obtaining written consent were enrolled in the study. In Group 1, chemomechanical preparation followed by mock laser therapy was carried out in which laser tip was applied but not activated. In Group 2, chemomechanical preparation followed by a laser irradiation was applied and activated. Postoperative pain scores were evaluated at baseline, 24 h, 48 h, and 72 h using the Visual Analog Scale. Preoperative and postoperative percussion pain scores were also recorded. Subjects needing rescue medication were recorded as well. Mann-Whitney U test and Wilcoxon test were used for intergroup comparison and intragroup comparison. The Chi-square test was used for comparing rescue medication. Results: There was significant reduction in pain scores in the laser group as compared to placebo group at all time points. There was also significant difference in the preoperative and postoperative percussion pain scores. 9 and 3 subjects required rescue medication in Groups 1 and 2, respectively. Conclusion: Laser irradiation following chemomechanical preparation led to significant reduction in postoperative pain and can be considered as a valuable adjunct.

Photoactivated disinfection (PAD) of dental root canal system - An ex-vivo study.

AIM: To investigate the efficacy of photo activated disinfection (PAD) in reducing colony-forming unit (CFU) counts of Enterococcus faecalis (E. faecalis) in infected dental root canals. The study compared the efficacy of PAD with conventional endodontic treatment (CET) and also a combination of CET along with PAD. MATERIAL AND METHODS: 53 maxillary incisors were taken for the study. Teeth were divided into 3 groups, CET (Group I) (n = 11), PAD (Group II) (n = 21), and a combination of CET and PAD (Group III) which consisted of (n = 21) samples, Group II and Group III were further divided into 2 subgroups, Group IIa, IIb and Group IIIa, IIIb. Strains of E. faecalis were inoculated in all the root canals. CET group samples were treated by chemo-mechanical preparation (CMP) alone, PAD samples were treated with laser alone at 2 different exposure time (4 min and 2 min). In the combination treatment, samples were treated initially by CET and then by PAD for a time period of 4 min and 2 min. Contents of the root canal were aspirated, diluted and plated in Tryptone Soya Broth (TSB) and plates were incubated for 24 h to observe the bacterial regrowth. RESULTS: Showed PAD used along with CMP reduced the bacterial load of E. faecalis by 99.5% at 4 min and 98.89% at 2 min. CONCLUSION: PAD may be an adjunctive procedure to kill residual bacteria in the dental root canal systems after standard endodontic root canal preparation.

Comparative outcome of revascularization in bilateral, non-vital, immature maxillary anterior teeth supplemented with or without platelet rich plasma: A case series.

Loss of pulp vitality in an immature permanent tooth arrests root development. This leads to tooth with open apex and weak lateral dentinal walls. Management of such necrotic teeth with immature roots poses several treatment challenges. The documented study was performed to evaluate and compare apexogenesis induced by revascularization, with and without platelet rich plasma (PRP) in non-vital, immature anterior teeth. Three patients having bilateral, non-vital, immature maxillary central incisors with apical periodontitis were recruited after institutional ethical clearance. Subsequent to chemo-mechanical preparation, revascularization with and without PRP was randomly induced in either of the tooth. The cases were followed-up clinically and radiographically at 6 and 12 months. There was a marked difference in periapical healing, apical closure and dentinal wall thickening of teeth treated by revascularization with PRP.

Comparación in vitro del comportamiento del irrigante durante dos técnicas de instrumentación con dos calibres de agujas para irrigación / Vitro comparison of the irrigant behavior during the implementation of two techniques of instrumentation with two caliber needles to irrigate

The success of endodontic therapy depends on cleaning and shaping the root canal system. There are two approaches to the root canal system debridement: Start at the apex and progressively enlarge the apical portion and then work coronally with increasingly larger instruments, or start with cervical flaring of the root canal and then progress apically using smaller instruments. The instrumentation is always associated to an irrigant solution, which is why the procedure is called chemo-mechanical preparation. The aim of this study was to compare and evaluate two manual instrumentation techniques (step-back and Crown-down) using different size irrigation needles (27G y 30G) and how this influences in the irrigant behavior. The study design was experimental with a nonprobabilistic convenientce sampling, with a 48 sample simulated in standardized transparent acrylic blocks of resin which were instrumented with the different techniques already mentioned and irrigated with different needle calibers after being divided in four groups. The data was obtained through a photographic record of each stage, they were also saved in a file and electronic forms to be analyzed later. The results obtained show that the lime more frequently allows that the irrigant occupies all the length of the conduct. Lime number 30 is used when implementing the telescopic technique; this is in the fifth stage of the process. However, the lime number 55 is used when implementing the Coronal-apical technique; this corresponds to the first stage. What is remarkable when implementing the Telescopic and Coronal-apical manual techniques of instrumentation associated to the conventional irrigation using 27G or 30G caliber irrigation needles is that it does not produce an appropriate irrigant liquid in the entire apical third.

Antimicrobial activity of calcium hydroxide pastes on Enterococcus faecalis cultivated in Root Canal Systems

The effectiveness of calcium hydroxide pastes: Calen™ and PMCC-Calen™ associated to chemo-mechanical preparation was assessed on Enterococcus faecalis grown within root canals. Seventy incisors were inserted into TSB medium, sterilized and contaminated with E. faecalis. Culture medium was replaced each 24 h and incubated at 37oC for 72 h. After chemo-mechanical preparation, root canals were filled with Calen™ or PMCC-Calen™ (7 or 14 days). Pastes were removed and teeth were inserted into test tubes containing Enterococcosel broth. Calen™ paste (maintained for 7 and 14 days) induced 70 percent elimination of enterococci and PMCC-Calen™ 100 percent elimination only after maintenance for 14 days. These medications were significantly more effective (p<0.001) than chemo-mechanical protocol alone and PMCC-Calen™ maintained for 7 days, both incapable to eliminate the viability of enterococci. Calcium hydroxide pastes demonstrated important adjuvant effects in the elimination of enterococci during chemo-mechanical preparation of root canal systems. When associated with PMCC, calcium hydroxide pastes should be maintained for at least 14 days.

A eficácia das pastas de hidróxido de cálcio: Calen® e Calen-PMCC® associadas ao preparo químico-mecânico, foi avaliada sobre Enterococcus faecalis cultivados no interior dos canais radiculares. Setenta incisivos foram inseridos em caldo TSB, esterilizados e contaminados com E. faecalis. O meio de cultivo foi substituído a cada 24 h, sendo incubados a 37oC por 72 h. Após o preparo químico-mecânico, os canais radiculares foram preenchidos com Calen® ou Calen-PMCC® (7 ou 14 dias). As pastas foram removidas e os dentes inseridos em tubos contendo caldo Enterococcosel. A pasta Calen® (mantida por 7 ou 14 dias) induziu a eliminação dos enterococos em 70 por cento dos dentes, enquanto a pasta Calen-PMCC® induziu a eliminação em 100 por cento dos dentes, somente após a manutenção por 14 dias. Tais medicações foram significativamente mais efetivas (p<0,001) do que o protocolo do preparo químico-mecânico e o Calen-PMCC® mantido por 7 dias, ambos incapazes de eliminar os enterococos. As pastas de hidróxido de cálcio demonstraram efeitos adjuvantes importantes na eliminação dos enterococos durante o preparo químico-mecânico dos sistemas de canais radiculares. Quando associada ao PMCC, as pastas de hidróxido de cálcio devem ser mantidas por pelo menos 14 dias.