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The aim of this study was to evaluate radiographically and histologically the pulpal and periapical response to self-adhesive (Rely X™ Unicem) and self-etching and self-curing (Multilink(®)) resin-based luting materials in deep cavities in dogs' teeth. Deep class V cavities (0.5-mm-thick dentin) were prepared in 60 canine premolars and the following materials were applied on cavity floor: Groups I/V-RelyX™ Unicem; Groups II/VI-Multilink(®); Groups III/VII-zinc phosphate cement (control) and; Groups IV/VIII-gutta-percha (control). Cavities were restored with silver amalgam. Animals were euthanized after 10 days (groups I-IV) and 90 days (groups V-VIII). Tooth/bone blocks were radiographed and processed for histopathological evaluation of pulp and periapical tissue response to the materials. All materials presented similar histopathological features and radiographic findings at both periods. The pulp tissue was intact. The apical and periapical regions and periodontal ligament thickness were normal. No inflammatory cells, resorption of mineralized tissue (dentin, cementum, and alveolar bone) or bacteria were observed. The lamina dura was intact and no areas of periapical bone rarefaction or internal/external root resorption were observed radiographically. It can be concluded that Rely X™ Unicem and Multilink(®) caused no adverse tissue reactions and may be indicated for cementation of indirect restorations in deep dentin cavities without pulp exposure., (© 2015 Wiley Periodicals, Inc.)

Purpose: To evaluate a structurally mature E. faecalis biofilm developed under anaerobic/dynamic conditions in an in vitro system., Methods: An experimental device was developed using a continuous drip flow system designed to develop biofilm under anaerobic conditions. The inoculum was replaced every 24 hours with a fresh growth medium for up to 10 days to feed the system. Gram staining was done every 24 hours to control the microorganism purity. Biofilms developed under the system were evaluated under the scanning electron microscope (SEM)., Results: SEM micrographs demonstrated mushroom-shaped structures, corresponding to a mature E. faecalis biofilm. In the mature biofilm bacterial cells are totally encased in a polymeric extracellular matrix., Conclusions: The proposed in vitro system model provides an additional useful tool to study the biofilm concept in endodontic microbiology, allowing for a better understanding of persistent root canal infections.

Introduction: The shaping ability of root canal instruments is determined by a complex interrelationship of parameters such as cross-sectional design and the ability to remove debris and the smear layer. The self-adjusting file (SAF) consists of a hollow, flexible instrument in the form of a compressible, thin-walled, pointed cylinder. The aim of this study was to compare the SAF with the ProTaper rotary file system, evaluating debris and smear layer removal and the presence of bacteria by using microbiological and scanning electron microscopy (SEM) evaluation., Methods: Fifty maxillary premolars were inoculated with Enterococcus faecalis for 30 days and then randomly distributed into 2 groups. Group 1 was prepared with ProTaper rotary instruments and irrigated with 30-gauge side-vented needles. Group 2 was prepared by using the SAF system with continuous irrigation. Bacteriologic samples were taken before and after preparation. All samples were then longitudinally split and analyzed under scanning electron microscopy. The scoring was carried out by 3 blinded evaluators., Results: In group 1, 40% of samples had negative cultures with postinstrumentation samples taken with paper points (S2a) and 45% with postinstrumentation dentin samples (S2b). In group 2, 20% of samples had negative cultures with S2a and 15% with S2b. Intragroup analyses evaluating the reduction in the number of colony-forming units (CFUs) from S1 to S2a and S2b demonstrated both preparation techniques were highly effective (P < .01). Further reduction of CFUs was observed when comparing S2a and S2b in group 1 (P < .05), whereas no difference was observed in group 2. Intergroup analysis demonstrated a statistically significant difference of CFUs at S2a and S2b (P < .05). SEM scores were consistent with the microbiology findings., Conclusions: The SAF system does not allow control of the apical enlargement, thus limiting the ability of the irrigants to achieve effective and predictable disinfection., (Published by Elsevier Inc.)

Objective: The aim was to compare the clinical and radiographic efficacy of enamel matrix derivative and self-hardening calcium hydroxide as direct pulp capping materials on decayed primary molars, with observation periods of 1, 6, and 12 months., Study Design: A clinical, randomized, controlled trial was performed, following the "split-mouth" design. A total of 90 primary molars were treated. Assignation of materials and operative initial side were selected in a randomized manner. Five outcome variables were considered: internal dentin resorption, pain, gingival sinus tract, root external resorption, and pathologic mobility. The appearance of any of these signs or symptoms was considered to be a failure of treatment., Results: Significant statistical or clinical differences were not found between the study groups. Two treatments were judged as failures, 1 per study group; both occurred during the first postoperative month., Conclusions: The technique used for direct pulp capping on primary molars in this study is recommended on the basis of the obtained clinical and radiographic results.

The antibacterial efficacy of intracanal medication with calcium hydroxide [Ca(OH)2], 2% chlorhexidine gel (CHX), and a combination of both [Ca(OH)2/CHX] was assessed in teeth with chronic apical periodontitis. Thirty-three canals were instrumented, randomly divided into three groups, and medicated with either Ca(OH)2, CHX, or Ca(OH)2/CHX. Bacteriological samples obtained from the operative field and the root canals before (S1) and after instrumentation (S2) in the first treatment session, and after medication (S3) in the second session 1 week later, were assessed for bacterial growth, observed by turbidity and in agar plates, and viable colony-forming unit (CFU) counts. Bacterial growth and CFU counts decreased significantly from S1 to S2 (Mann-Whitney, p<0.05). Differences in growth and counts between S2 to S3 were not statistically significant for all three intracanal medication groups. It was concluded that the antibacterial efficacy of Ca(OH)2, CHX, and Ca(OH)2/CHX was comparable.

Purpose of this paper is to undertake a bibliographical review on the diagnosis, prevention and treatment of pain in endodoncy, in order to provide the reader with an updated guide on the clinical control of pain of dental origin.

Sixty permanent human teeth, all with straight, accessible root canals were analyzed in vitro in order to compare the sealing capacity of three different instrumentation and obturating techniques, namely: Obtura system, sonic and ultrasonic techniques, and modified lateral instrumentation and condensation technique. Root canals were instrumented and obturated according to guidelines of each technique. Three layers of varnish were then applied, except on a 1 mm area around the apical foramen. The pieces were immersed in 5% methylene blue, making sure that the apical foramen kept in contact with the solution. Next, they were introduced in an incubator for a 48-hour period, at a temperature of 37 degrees C. Longitudinal sections were subsequently cut and observed on the stereoscopic microscope. Penetration values of the dye in each specimen were obtained by means of a micrometric slide. These were analyzed in a computer by the Student T method, yielding a value of P greater than 0.5, meaning there is no statistical difference in the comparison of the three techniques under study.