Fabio de Almeida Gomes

Persistent extra-radicular bacterial biofilm in endodontically treated human teeth: scanning electron microscopy analysis after apical surgery: SOUSA et al.

Biofilms are the main cause of endodontic failures. Even the best executed endodontic treatment can fail, when the infection is resistant to treatment or when it is located in inaccessible areas, such as the external surface of the root apex. The purpose of this study was to evaluate, by scanning electron microscopy, the presence of bacterial biofilm on endodontically treated teeth considered clinical failures and suitable for apical surgery. Root apices were collected from 20 teeth undergoing apical surgery and one negative control and analyzed under SEM. Digital photomicrographs of the root apices of 21 specimens at different magnifications were taken. Data were analyzed using descriptive statistics. Apical biofilms were observed in 100% of root canal treatments considered endodontic failure. Topographical analysis of the root apices revealed areas of resorption, microcracks, and apical foramina in 90%, 80%, and 50% of cases, respectively. Within the limits of this study, it can be concluded that endodontic failures present bacterial biofilm in areas inaccessible to conventional endodontic treatment, such as the external surfaces of the root apex.

Intentional Replantation of an Avulsed Immature Permanent Incisor: A Case Report

Abstract This case report discusses the successful endodontic treatment of an open apex maxillary right permanent central incisor that had been avulsed and incorrectly replanted in a 7‐year‐old patient. The tooth was carefully re‐extracted followed by cleaning of the alveolar socket and immediate replantation. However, pulp necrosis was diagnosed, and regenerative endodontic treatment was performed. The root canal system was disinfected by passive ultrasonic irrigation with 2.5% sodium hypochlorite. At the first visit, the tooth was repositioned and immobilized with an appropriate semirigid splint. After 14 days, the splint was removed, and the diagnosis of pulp necrosis was confirmed by thermal testing. The root canal was emptied, disinfected, and filled with calcium hydroxide paste, which was left in place for 7 days. At the third visit, calcium hydroxide was removed with hand files and passive ultrasonic irrigation, and the canal was filled with a mixture of double antibiotic paste (metronidazole/ciprofloxacin) and zinc oxide. The antibiotic paste was left in place for 30 days. At the final visit, the paste was removed and the periapical area stimulated with a #80 K‐file to encourage clot formation within the pulp cavity. A mineral trioxide aggregate paste cervical plug was placed, and the tooth was restored with glass ionomer cement. Clinical and imaging (radiographic and tomographic) follow‐up at 3, 6, 12, and 36 months showed endodontic success with continued root formation.

Influence of reuse and cervical preflaring on the fracture strength of reciprocating instruments

Objective: This study sought to assess the influence of cervical preflaring and reuse after resterilization, on fracture strength and plastic deformation and/or surface cracking in reciprocating nickel–titanium [NiTi] endodontic instruments after root canal instrumentation of extracted human teeth. Materials and Methods: Forty engine-driven reciprocating NiTi instruments (20 Reciproc® [RC], VDW; 20 WaveOne® [WO], Dentsply) were used in root canal instrumentation of extracted human molars. A total of 485 human upper molars with similar anatomical features were selected and randomly distributed across four groups according to the instrumentation procedures performed (G1 and G3: RC; G2 and G4: WO). Reciprocating instruments were used as per manufacturer instructions. In groups G3 and G4, cervical preflaring was performed prior to instrumentation. After each use of each instrument, sterilization was repeated and scanning electron microscope (SEM) images were obtained to check for plastic deformations and/or cracks on instrument surfaces. Each instrument was used repeatedly until fracture occurred. Results: Regardless of flaring, RC files exhibited greater fracture strength than WO instruments (P<0.01) with and without preflaring. Cervical preflaring significantly reduced the risk of instrument fracture (P<0.01). No plastic deformations were observed before fracturing. However, cracks were found on WO instruments shortly after their first use. RC and WO instruments resisted fracturing after autoclave sterilization. Conclusions: Cervical preflaring allowed a significant increase in the number of times RC and WO files could be reused safely.

In vitro analysis of the internal anatomy of lower incisors by cone beam computerized tomography

Introduction: For the success of endodontic treatment, the knowledge of the internal anatomy becomes essential. Objective: to analyze the prevalence of lower incisor canals in a clinical and tomographic analysis. Material and methods: 148 lower incisors were used, measured, and evaluated through periapical radiograph and computed tomography. Results: in relation to the number of canals, 107 teeth (72.3%) presented a single canal, while 41 teeth (27.7%) presented two canals. Of the 41 teeth presenting 2 canals, 3 teeth presented independent canals (2.03%) and 38 teeth had 2 canals that joined at some point of the canal path (25.67%). Conclusion: The prevalence of two canals in the lower permanent human incisors was 27.7%; of these, 2.03% were independent. The main point of root canal union was at the apical third (20.94%). The most commonly found root canal shape was round in cervical third, flattened in middle third, and round in third apical.

Decompression of a Large Periapical Lesion: A Case Report of 4-Year Follow-Up

This case report described the endodontic treatment and decompression of an extensive lesion in the anterior region of the mandible, detected during clinical and radiographic examination, in a patient with a complaint of slight tenderness to palpation in the area of mandibular right lateral incisor and canine. These teeth had been accessed without proper clinical evaluation, and their pulp tissues were exposed. The periodontal tissues were healthy, with no signs of inflammation or fistula. On radiographic examination, a radiolucent lesion with well-defined borders was seen extending from the distal root of mandibular left second premolar to the mesial root of mandibular right second premolar. Central and lateral mandibular left incisors were unresponsive to thermal pulp testing and exhibited coronal discoloration, consistent with a diagnosis of pulp necrosis. Due to persistent discharge from the root canal system during endodontic procedures despite application of intracanal medicament (calcium hydroxide paste), the decision was made to biopsy and decompress the lesion and conclude endodontic treatment. Histopathologic examination revealed a periapical granuloma. After endodontic treatment of the involved teeth, at 4-year clinical and radiographic follow-up, the affected region was almost completely repaired.

Management of Six Root Canals in Mandibular First Molar

Success in root canal treatment is achieved after thorough cleaning, shaping, and obturation of the root canal system. This clinical case describes conventional root canal treatment of an unusual mandibular first molar with six root canals. The prognosis for endodontic treatment in teeth with abnormal morphology is unfavorable if the clinician fails to recognize extra root canals.

Prevalência de lesão endodôntica em pacientes diabéticos

Objective: To investigate the prevalence of apical periodontitis (AP) in diabetic and nondiabetic patients. Methods: Cross-sectional study, in which the radiographic records (panoramic and full-mouth periapical radiographs) of 80 patients, being 40 type II diabetic patients and 40 nondiabetic subjects, had the periapical and endodontic regions of all teeth present evaluated by means of the periapical index score. Data was analyzed through BioEstat 5.3TM software. Results: At least one tooth was found with apical periodontitis in 90% (n=32) of the diabetic patients and in 52% (n=21) of nondiabetic subjects (p=0.0001). Regarding root-filled teeth, 44% (n=51) presented AP amongst the diabetic patients, whereas only 17% (n=17) (p=0.0004) were affected in the control group. Conclusion: According to these results, type 2 Diabetes Mellitus is associated with an increase in the prevalence of apical periodontitis. doi:10.5020/18061230.2014.p163

Filling lateral canals: Influence of calcium hydroxide paste as a root canal dressing

CONTEXT The use of intracanal medication aims to provide antimicrobial activity in the root canal system, leading to a more satisfactory condition for root canal obturation. However, it is important to evaluate whether such medication would affect the sealing-off from the main root canal of ramifications such as lateral canals. AIM Evaluate the influence of calcium hydroxide [Ca(OH)2] paste on the filling of lateral canals. SETTINGS AND DESIGN Ex vivo quantitative laboratory study. MATERIALS AND METHODS Sixty single-rooted teeth with lateral canals created were used, 10 teeth per group. Group A was described respectively as lateral condensation technique (subgroup 1), thermomechanical compaction (subgroup 2), and continuous wave of condensation (subgroup 3). In Group B, subgroups 4, 5, and 6 were filled with Ca(OH)2 for 7 days before filling using the techniques applied in subgroups 1, 2, and 3. Radiographic evaluation was performed to count the number of filled lateral canals in each group. The teeth were cross-sectioned over the lateral canals; thus, 180 specimens were obtained. Each specimen was immersed in a polyester resin. Digital images were obtained and specific software (Image Tool; ) was used to evaluate the number of obturated lateral canals and the filling length in each lateral canal of groups. STATISTICAL ANALYSIS USED Data were statistically analyzed using SPSS 12.0 for Windows (Descriptive statistical analysis and Newman-Keuls test). RESULTS A greater number of simulated lateral canals were filled in Group A (91.1%). Group B had less filled lateral canals (33.3%). The sealing of lateral canals was statistically different between Group B (26.15%) and Group A (74.43%). CONCLUSIONS According to the radiographic analysis and the linear filling measurement, the use of Ca(OH)2 decreased the number and the length of sealed lateral canals.