For many years, it has been the constant endeavor of researchers to understand the complexities of root canal anatomy. This systematic review aimed to analyze the root canal morphology of primary mandibular second molar using different diagnostic aids in different ethnic population. An exhaustive search was undertaken to identify published literature related to the root anatomy morphology of the primary mandibular second molar. Using a combination of keywords, search was done up to August 2018 in PubMed, The Cochrane Central Register of Clinical Trials, and Science Direct. The included data consist of type of population, number of teeth per study, number of root canals, and type of root canal configuration. A total of 10 articles were selected for the review. The most common morphology in primary mandibular second molar consists of 3 canals (two mesial and one distal) in 63% of the teeth examined. The mean root length was estimated to be 8.2 mm in the mesial and 8.6 mm in the distal roots. The review concluded that there are variations in canal morphology and number of canals based on the ethnic origin of the study population. The common canal morphology in primary mandibular second molar is 2 separated roots (mesial and distal) with 3 canal systems. Vertucci's Type IV (22) and Type I (11) canal configurations were the most prevalent in the mesial and distal roots, respectively.

Aim of the Study: This study aims to investigate the outcomes of endodontic treatments performed by endodontic postgraduate students at the Riyadh Elm University College of Dentistry. Materials and Methods: The records of 187 patients with 432 teeth endodontically treated by endodontic postgraduate students at Riyadh Elm University College of Dentistry from February 2013 to February 2017 were randomly selected. In all, 151 patients were lost to follow-up. Clinical and radiographic examinations were performed in 135 teeth of 36 patients. Two qualified endodontists reviewed the results of clinical and radiographic examinations. Outcomes were healed, healing, or diseased. Data were coded and statistically analyzed. Results: Overall results of endodontic treatment were healed teeth in 68.1%, healing teeth in 27.4%, and diseased teeth in 4.4%. The proportions of healed teeth in one and two visits were 64.3% and 90.5% (P = 0.083), respectively. The acceptable quality root canal filling had a higher healed rate (74.4%) than long or short root canal filling (P = 0.027). The presence of apical periodontitis significantly affected the success of endodontic treatment (P = 0.002). Conclusion: The outcome of this study is similar to those of previous studies, despite the limited sample size.

Introduction: This study aimed to assess the knowledge and practice of dentists in Palestine toward pulp protection protocols under composite restorations and to find any associations with age, years of experience, and gender. Materials and Methods: A questionnaire was randomly distributed among 500 licensed dentists. It included six questions. The first three focused on demographic variables (gender, years of experience, and type of practice). The others focused on the protocols followed in three different Class I cavity scenarios: shallow (remaining dentine thickness [RDT] >1.5 mm), moderate (1.5 >RDT >0.5 mm), and deep (RDT <0.5 mm). For all scenarios, the questions were about using calcium hydroxide, resin-modified glass ionomer (RMGI), flowable composite, and dentin bonding agents under composites as the final restoration. Results: The response rate was 61%. There was a significant difference in the protocols the respondents chose for restoring shallow (P < 0.001) and deep (P < 0.001) cavities. However, there was no significant difference in the protocols the respondents chose for moderate cavities (P = 0.576). There was a significant association between the time since graduation and the protocol used for all cavity scenarios (P < 0.001). There was significant association between the gender and the protocol used in shallow (P = 0.001) and deep (P = 0.002) cases, but there was no association between gender and the protocol chosen in moderate cases (P < 0.418). There was no significant association between the protocol used and the type of practice in shallow (P < 0.236) and moderate (P < 0.055) cavities, but there was a significant association between the protocol used in deep cavities and the type of practice (P < 0.001). Conclusion: Irrespective of the cavity depth, there was an inconsistent implementation of pulp protection protocols among the respondents.

Aims: The aim of this study was to test the cytotoxicity of some hemostatic agents used in periapical surgery to primary human periodontal and bone cells. Materials and Methods: Primary human periodontal ligament and bone cells were divided into five experimental and two control groups. In each of the experimental groups, the cells were cultured in complete media containing various concentrations of different hemostatic agents: epinephrine, aluminum chloride, aluminum sulfate, ferric sulfate, or tranexamic acid. The cytotoxicity was evaluated at 1 min, 5 min, and 24 h. Regular complete medium and sodium hypochlorite were used as positive and negative control groups, respectively. The number of viable cells was investigated using MTT assay. The data were analyzed statistically at the 95% confidence interval. Statistical Analysis Used: The statistical analysis was done using Kruskal–Wallis and multiple comparisons tests. Results: The cytotoxicity of all hemostatic agents was time and concentration dependent. Epinephrine and tranexamic acid showed mild or no toxicity to both human periodontal and bone cells at all-time points. Aluminum chloride, aluminum sulfate, and ferric sulfate were moderately to highly toxic to the cells. No significant difference was found between epinephrine and tranexamic acid (P < 0.05). Conclusions: Epinephrine and tranexamic acid tended to be nontoxic or mildly toxic to periodontal ligament and bone cells. Both of them might be considered as the appropriate hemostatic agents for surgical endodontics.

Background: Laser systems play an eminent role in endodontic treatment; however, some parameters should be investigated so that damage to the periodontal tissues can be prevented. Hence, in this context, the purpose of this study was to evaluate the temperature rises during the application of different power levels of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser and erbium-doped yttrium aluminum garnet (Er:YAG) laser to the external root surface of permanent teeth. Materials and Methods: Sixty mandibular single-rooted premolars were selected and prepared chemomechanically. Nd:YAG laser (Group I) activated irrigation was performed in 30 teeth and remaining 30 received Er:YAG laser (Group II) treatment at three different power levels (1, 1.5, and 2.0 Watt), applied to 10 samples from each group. Type K thermocouple wire, along with a digital calibrated thermometer, was used to measure the temperature changes on the external root surface. Data were assessed with unpaired Student's t-test and two-way ANOVA. Results: With increasing power levels, temperature of external root surface also increased to some extent in both the groups. For apical third, at power level of 1.5 and 2 Watt, the difference in mean temperature between the two groups was found to be significant (6.30°C and 7.75°C; P = 0.005 and 9.11°C and 10.05°C; P = 0.036), whereas for middle third region, it was found that at power level of 2 Watt, the difference in mean temperature between the two groups was significant (6.69°C and 7.91°C; P = 0.007). Conclusion: Both Nd:YAG laser and Er:YAG laser at various power levels lead to rise in temperature on the external root surface, but the temperature changes in all the tested groups remained below the critical threshold.

Aim: This study aimed to analyze dental undergraduates' perceptions about the difficulties they are facing while performing root canal therapy at a Turkish university, using a survey to identify students' answers to difficulties and to make a dissertation by the educators about possible resolutions. Materials and Methods: One hundred and six undergraduates who had experienced endodontic theoretical and preclinical education before clinical procedures enlisted in endodontics at the College of Dentistry at Biruni University were involved in this survey in 2018. All of the undergraduates who had experienced the same clinical procedures answered the survey based on problems at particular stages of root canal therapy. A Chi-squared test was used to determine statistical significance between different parameters (P < 0.05). Results: For the first 13 parameters, students had the most difficulty in radiography (50.9%), root canal identification (67%), and obturation (54.7%) procedures. For these parameters, respondents mostly did not report any trouble; especially, in irrigation (87.7%) and intracanal medication (89.6%) procedures. Conclusion: Assessment of the major undergraduate difficulties during endodontic treatment may assist the development of teaching methods during preclinical and clinical teaching.

Aim: The aim of this study is to assess radiographically the technical quality of root canal treatments (RCTs) performed by students at the Dakar Dental School. Materials and Methods: Out of 420 patients who had undergone RCTs, 501 teeth were randomly selected. Forty-eight teeth were excluded and the final sample involved 453 endodontically treated teeth. The length and the density of the root filling were evaluated for each filled root of each tooth. The presence of procedural errors was also evaluated. Descriptive statistics were used for expressing the frequencies of criteria and Chi-square test was used for comparing qualities of RCTs in terms of tooth locations, tooth types and academic level of students. The level of students, the significance level was set at 0.05. Results: From the 453 RCTs, 63.6% were acceptable. The rate of adequate RCTs was higher in the maxilla than in the mandible (P = 0.022) and in the premolars (75.5%) followed by the anterior teeth (69.7%) and the molars (49.2%) (P = 0.026). The difference was not significant in terms of level of students (P = 0.429). Inadequate density was found in 27.8%, whilst underfilling and overfilling were found in 26.5% and 7.3%, respectively. The frequency of procedural errors was 2%. Conclusion: The technical quality of RCTs performed by undergraduate students at the Dakar Dental School using step-back preparation and cold lateral condensation was classified as acceptable in 63.6% of the cases.

Introduction: The aim of this study was to determine the frequency of the occurrence of endodontic complications according to the dentists of the town of Abidjan and to identify the various types encountered so as to prevent them. Materials and Methods: This was a descriptive, cross-sectional prospective study. A survey form was randomly distributed to 150 dentists working in 128 private and public dental clinics in the town of Abidjan. The dentists were asked about the daily average number of patients treated, the frequency with which canal treatments were performed, and the complications encountered by dentists. The information collected was analyzed by means of EPI Info version 06.01 software. Results: A total of 135 dentists replied to the questionnaires; nearly all of them (94.8%) stated that they had encountered complications during endodontic treatment. Canal wall damage represented 54.68% of the complications when generating the access cavity. Fracturing of instruments was a frequent occurrence during exploring the root canal (72.58%) and during canal shaping (55.47%). Overfill of the gutta-percha cone and/or the cement for obturation was the complication that occurs most with canal obturation (55.47%). Flare-up without swelling was often encountered postoperatively (81.49%). Conclusion: Complications occurring during endodontic therapy remain a concern. Their prevention necessitates rigorous adhesion to the treatment protocols.

Introduction: The present study evaluated the change in the temperature of the external root surface of simulated immature teeth obturated with high-temperature injectable thermoplasticized gutta-percha. Materials and Methods: Root canals of 60 mandibular premolars were enlarged till size # 6 peeso freely passed through the apex. After placement of an apical barrier of 4 mm of mineral trioxide aggregate (MTA), two K-type thermocouples were attached at middle and apical thirds. The canals were obturated using high-temperature injectable thermoplasticized gutta-percha with either no sealer; AH plus sealer; or MTA Fillapex sealer. Maximum temperature rise was measured and evaluated. The data were analyzed using two-way ANOVA test. Results: The temperature increased after 4 s of placement of heated gutta-percha. There was no significant effect of sealer placement on the peak rise in temperature at the middle third (P < 0.05). There was no difference between the AH plus and MTA Fillapex groups (P = 0.42). Conclusions: The use of thermoplasticized gutta-percha can significantly increase the temperatures on the external root surface.

Aim: The aim of this study was to evaluate and compare the cutting efficiency and dentinal defect rates using two single-file continuous rotary nickel–titanium instruments. Materials and Methods: Thirty-two resin endo training blocks and 48 mesiobuccal roots of extracted human first lower molars were divided into five groups (16 for each group). Roots were checked for the homogeneities of root canal dimensions, thickness of dentin walls, and curvatures using images of X-ray radiographs on AUTOCAD software. Two groups of resin blocks and two groups of mesiobuccal canals were instrumented using two continuous rotary nickel–titanium instruments (Neoniti A1 and OneShape), the remaining group (control group) of mesiobuccal canals was left intact. The cutting efficiencies of instruments were quotients of the loss weights of specimens, and the time needed for instrumentation. ANOVA and post hoc Tukey tests were used to analyze the differences among the experimental groups. The cracks on the sectioned root surfaces at 3-, 6-, and 9-mm levels were recorded. Fisher exact test was used to analyze the differences among the experimental groups. Results: Cutting efficiency of OneShape was greater than that of Neoniti on both resin and human root canals (P < 0.05). There was no significant difference between dentinal defects created at different levels of canals by two kinds of nickel–titanium instruments (P > 0.05). Conclusions: OneShape instrument was more efficient than Neoniti on both kinds of root canals. Both instruments created dentinal defects on root canal walls.

Since time immemorial, endodontics have proved to be an ultimate tooth savior. Hemisection is a conservative procedure where a part of hopeless multi-rooted teeth, with better retention, is preserved rather than saving the tooth as a whole. But with time, the extraction socket shows alveolar ridge resorption thus complicating the prosthetic procedure. Thus, a new technique of socket preservation evolved preventing such dimensional changes in postextraction socket. This case report shows grossly carious first and second mandibular left molar with furcation involvement in the second molar of a healthy 25-year-old male patient. Following endodontic treatment and hemisection, autologous platelet-rich fibrin was placed in the extraction socket, and the patient was followed at 1, 3, 6, and 12 months for hard- and soft-tissue evaluation, clinically and radiographically. The fixed prosthesis was placed at the end of 3^rd month. Radiographs at 6^th and 12^th months showed little resorptive changes with better healing, occlusion, and function clinically.

Aspirin is one of the most effective oral analgesic agents available worldwide without prescription. Aspirin tablets can be directly placed on the painful tooth and adjunct mucosa to relieve pain and avoid dental visits. However, aspirin is acidic in nature and its protein coagulation effects can cause severe chemical burns to the surrounding mucosa when placed directly. Here, we describe a rare case of chemical burn caused by the direct placement of an aspirin tablet on a painful tooth. A 55-year-old healthy African female presented to the clinic with a history of pain in the right maxillary region. The patient stated that she had placed aspirin locally to relieve her toothache for a few days. On intraoral examination, a grayish-white fibrin-coated ulcer was observed on the buccal mucosa near the painful tooth, extending to the upper and lower buccal vestibules, up to the premolar area. The source of pain was resolved by root canal treatment of #17, and the patient was advised to discontinue the direct application of aspirin to oral tissues. Two weeks later, the lesion had healed entirely without scarring. This case highlights the differences in the degree of clinical presentation of the lesion and the importance of considering the injudicious use of aspirin as a potential cause of white lesions in the oral cavity.

The management of intrusive luxation varies depending on the patient's age, stage of root development, and severity of the trauma. These kinds of injuries are associated mostly with severe damage to the pulpal tissue, periodontium, and the tooth. The aim of this case report is to present multidisciplinary management of complete intrusion of maxillary central incisors in a 9-year-old healthy girl with external root resorption. The root canals were cleaned and medicated with calcium hydroxide then the teeth were extruded by an orthodontist. After two months, a 4 mm apical plug with mineral trioxide aggregate was placed in the apical third of the canals and the remaining of the canal was obturated with thermoplasticized gutta-percha. Cervical root resorption was noticed during the follow-up evaluation and was surgically managed.

The roots and canals of maxillary second premolar have several typical anatomical features, as well as a great number of anomalies. The awareness toward atypical anatomy can be a critical factor in determining the success of endodontic therapy. This case report of 32-year-old healthy female patient describes the successful endodontic therapy of a left maxillary second premolar with Type VI configuration according to Vertucci's classification. The pulp of the tooth was previously initiated with asymptomatic apical periodontitis. An operating dental microscope was used to locate the orifices of the canals. Recall radiograph shows reduction in the size of the apical radiolucency.

Traumatic dental injuries may cause the loss of a tooth's pulp vitality before the development of the root has been completed. A 12-year-old boy complained of a broken crown of one of his upper front tooth due to falling down. The tooth had a history of previous trauma 1 year ago. Clinically, the tooth was discolored with complicated crown facture. Intraoral periapical radiograph revealed an open apex of 1 mm in width. Mineral trioxide aggregate (MTA) plug, placed orthogratelly on the apical part, has proven a successful outcome based on a 3-year follow-up. In conclusion, MTA plug is a treatment of choice for cases of small open apex (1-mm diameter or less) of traumatized nonvital permanent teeth.