Present status and future directions-Mechanisms and management of local anaesthetic failures.

AIM: To review variables and management techniques that may affect anaesthesia failure during root canal treatment and methods of overcoming anaesthesia failure. METHODOLOGY: The PubMed and Cochran databases were searched for evidence-based investigations regarding pain during needle insertion, pain on injection, efficacy of the anaesthetic solutions and anaesthesia techniques, and premedication. RESULTS: Variables such as pain on injection, premedication with various types of drugs, volume of anaesthetic solutions, supplemental anaesthetic techniques, and additives to the anaesthetic solutions may influence pain perception during root canal treatment. Differences between teeth with healthy pulps versus those with irreversible pulpitis should be considered when the effects of variables are interpreted. However, there are several concerns regarding the methodology of investigations that have evaluated anaesthesia success rates. CONCLUSION: Several variables may influence anaesthesia success rates. There are conditions that may help to predict a patient's pain during endodontic procedures. These conditions could be overcome either by employing methods such as premedication with a non-steroidal anti-inflammatory drug prior to the treatment visit or by using supplementary techniques before or during the treatment. However, investigators need to be more careful when reporting details of their studies to reduce concerns regarding their study bias.

Buffered Lidocaine With Sodium Bicarbonate did not Increase Inferior Alveolar Nerve Block Success Rate in Patients Having Symptomatic Irreversible Pulpitis.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Effect of buffered 4% lidocaine on the success of the inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: a prospective, randomized, double-blind study. Schellenberg J, Drum M, Reader A, Nusstein J, Fowler S, Beck M. J Endod 2015;41(6):791-6. SOURCE OF FUNDING: The study was supported by Meyers/Reader Graduate Endodontic Support Fund TYPE OF STUDY/DESIGN: Double blinded randomized controlled trial.

Assessing the Impact of Mandibular Molar Root Length on Success in Supplemental Intraligamentary Injection for Irreversible Pulpitis.

Introduction: This study investigates the influence of root length in mandibular molars with irreversible pulpitis on the success of supplemental intraligamentary injection following an inferior alveolar nerve (IAN) block. Various factors, including anatomical location, tooth type, and anesthetic solution, may affect supplemental anesthesia success. Materials and Methods: A total of 251 patients diagnosed with irreversible pulpitis in mandibular first or second molars underwent buccal infiltration anesthesia (4% articaine with 1:100,000 epinephrine) after IAN block injection (3% prilocaine and 0.03 IU/mL of felypressin). Fifty patients experiencing pain during access cavity preparation received supplemental intraligamentary injection (0.3 mL of 2% lidocaine with 1:80,000 epinephrine) at each mesial and distal line angle. The root length of treated teeth was recorded using an apex locator. Data analysis involved independent t-tests, Chi-square tests, and logistic regression. Results: Successful supplemental intraligamentary injection was observed in 21 (42%) out of 50 patients. No significant correlation was found between the mean length of mesiobuccal (P=0.61), mesiolingual (P=0.34), or distal (P=0.60) canals of mandibular molars and the injection's success. Logistic regression analysis, however, revealed a significant impact of mesiolingual canal length on the success rate [OR 0.09 (0.01-0.79), P=0.030]. Conclusion: The root length of mandibular first and second molars does not significantly affect the success of supplemental intraligamentary injection.

The Outcome of Prescribing Antibiotics for the Management of Patients with Endodontic Infections.

OBJECTIVE: This study aimed to evaluate the efficacy and duration of antibiotic therapy with different regi- mens of antibiotics for patients presenting with primary and secondary endodontic infections. METHODS: In a case series outcome study, all patients needing antibiotics due to endodontic infection were included. In patients with no history of hypersensitivity to penicillin, amoxicillin was used as the first-line antibiotic, followed by adding metronidazole if the symptoms did not show signs of recovery during the first 24 hours after prescribing the medication. If a patient did not respond to the combination of amoxicillin and metronidazole, amoxicillin was substituted with a parental penicillin G procaine. Patients who had sensitivity to penicillin received clindamycin. In cases where drainage was possible, the effect of the procedure on the success rate of antibiotic therapy was evaluated. All patients were asked to continue taking the antibiotic for up to two days following the relief of symptoms. Data were analysed by Chi-square, Fisher exact test, Indepen- dent t-test, and One-way ANOVA. RESULTS: Over a period of 6 years, 97 patients were eligible to be included in this study. In patients with no history of sensitivity to penicillin (95.9% of the patients), 52.7% of patients on amoxicillin and 43% of patients on amoxicillin plus metronidazole overcame the endodontic infections. In addition, drainage significantly increased the success rate of antibiotic therapy when amoxicillin was prescribed (p=0.046). There were no significant differences between the gender, age, type of tooth, need for primary or secondary endodontic treatment, previous history of infection, need for drainage or duration of antibiotic consumption (p>0.05), and the success of antibiotic prescription. However, patients who received a single antibiotic (either amoxi- cillin or clindamycin) had significantly shorter average times for the recovery of symptoms (p<0.05). CONCLUSION: Amoxicillin helped patients recover from endodontic infection symptoms in more than half of the cases. However, it is necessary to monitor the patients to understand if they should be needed further treatment, such as another antibiotic or drainage. (EEJ-2022-11-138).

Variables That Affect the Ability to Find the Second Mesiobuccal Root Canals in Maxillary Molars.

Introduction: The study aimed to investigate the influence of various factors on the localization of the second mesiobuccal (MB2) canal in maxillary molars, a commonly missed canal during endodontic treatment. Materials and Methods: A comprehensive assessment of maxillary molars treated over three years with a dental operative microscope was conducted. Factors such as patient gender, age, tooth type, pulp status, pre-operative cone-beam computed tomography (CBCT), and treatment modality were examined. Statistical analyses included chi-square and multiple logistic regression. Results: Among 333 treated maxillary molars, the MB2 canal was identified in 60.1%. The prevalence of MB2 canals was significantly higher in the first molars (72.3%) compared to the second molars (40.2%; P=0.001). Multiple logistic regression models showed that gender, tooth type, and treatment modality emerged as significant determinants of MB2 canal localization: males [odds ratio 3.01(CI 95%:1.71-5.32), P<0.001], first molar tooth [odds ratio 4.26 (CI 95%:2.53-7.18), P<0.001] and secondary endodontic treatment [odds ratio 0.06 (CI 95%: 0.004-0.890), P<0.04]. Conclusions: Patient gender, tooth type, and treatment modality play pivotal roles in the identification of the MB2 canal. Additionally, the availability of pre-operative CBCT imaging was associated with a heightened ability to locate the MB2 canal.

Conservative Treatment of an Infected Lateral Canal: A Case Report with a 4-Year Follow-up.

Connective tissues in lateral canals mostly remain vital even after pulp necrosis of the main canals. However, lateral canals may become necrotic following the pulp necrosis of the main root canal or after root canal therapy. This case report presents a maxillary central incisor with a necrotic lateral canal and a sinus tract that initially showed healing following the primary endodontic treatment but showed infection after fiber-post placement and permanent restoration with composite resin. Tracing the sinus tract did not reveal the reason for the infection; however, cone beam computed tomography (CBCT) confirmed a lateral radiolucency of the maxillary right central incisor as the only reason for the return of the infection. A conservative re-treatment approach was performed, replacing the fiber post with gutta-percha and root canal sealer. Successful outcome was achieved with a conservative approach; however, it took some time for the sinus tract to heal. In the case of lateral canal infection, sealing the main root canal space could heal the lesion even without lateral canal negotiation. If the main root canal seal is disturbed, re-cleaning and obturating the main root canal could be successful.

Comparing the Efficacy of Premedication with Ibuprofen in Combination with an Inferior Alveolar Nerve Block and Primary Buccal Infiltration in Mandibular Molars with Irreversible Pulpitis: A Triple-blinded Randomized Clinical Trial.

Introduction: This study aimed to determine the success rate of the combination of buccal infiltration (BI) and inferior alveolar nerve block (IANB) injections in irreversible pulpitis in mandibular molars after premedication with ibuprofen. Materials and Methods: From 132 patients participated in the study, 120 patients were included. One hour before root canal treatment, patients with mandibular molars with symptomatic irreversible pulpitis received either a 600 mg ibuprofen capsule or a placebo. All patients received 2% lidocaine with 1:80000 epinephrine and 4% articaine with 1:100000 epinephrine for IANB and BI, respectively. Patients' pain was evaluated using the Heft-Parker visual analog scale during the preparation of access cavity, exposure of pulp, and instrumentation of root canal. The success of anesthesia was defined as the absence of pain or mild pain. The Chi-square and t-test were employed for data analysis. Results: The difference between patient age and gender in the two groups was not significant (P>0.05). The anesthesia success rate was 85% in the premedicated and 70% in the placebo group, with statistically significant results (P=0.049). Conclusion: Based on this triple-blinded randomized clinical study, mandibular molars with irreversible pulpitis were not thoroughly anesthetized by a combination of IANB+BI after premedication with ibuprofen (600 mg), even though anesthesia success was improved significantly by ibuprofen premedication.

The Effect of the Anatomic Variables on the Success Rate of Anesthesia in Maxillary Molars with Irreversible Pulpitis.

INTRODUCTION: Obtaining anesthesia of teeth with irreversible pulpitis is 1 of the most challenging issues in endodontic practice. The aim of this study was to evaluate the effect of anatomic variables on the success rate of anesthesia in maxillary molars with irreversible pulpitis. METHODS: Patients who had maxillary molars with irreversible pulpitis and who had already had a cone-beam computed tomographic (CBCT) scan performed were included in this study. After infiltration injection of an anesthetic solution, the success rate of anesthesia was recorded by asking the patients to rate their pain during access cavity preparation and root canal instrumentation as well as their need for a supplementary injection during the treatment. The distance of the palatal root to the buccal cortical plate was calculated using the Romexis Viewer (Planmeca, Helsinki, Finland) measuring tools in both the axial and coronal views. Data were analyzed by chi-square and t tests as well as receiver operating characteristic curve analysis. RESULTS: Forty-seven maxillary first and second molar teeth were eligible to be included in this study. The overall success rate of anesthesia was 63.80%. The palatal roots that had their apex located more than 12.34 mm from the buccal cortical plate in the axial view, and 12.46 mm in the coronal view had a higher chance of anesthesia failure compared with the teeth with smaller distances. The presence of the maxillary sinus between the cortical plate and roots had no significant impact on the efficacy of anesthesia (P > .05). CONCLUSIONS: The potential of anesthesia failure during the treatment of irreversible pulpitis in maxillary molars with a divergent palatal root is significantly higher than in teeth with shorter distances from the palatal root apex to the buccal cortical plate. If a patient already had a CBCT scan done for other reasons or the CBCT is available in his or her records, a dental practitioner can use it to predict anesthesia success for maxillary molars with irreversible pulpitis.

The Effect of Long Service Life on the Accuracy of Dentaport ZX Electronic Apex Locator.

Introduction: Electronic apex locators are among the most acceptable instruments for determining root canal length. The present study aimed to evaluate the effect of long service life on the accuracy of the Dentaport Root ZX (DP ZX) electronic apex locator (EAL). Materials and Methods: In this study, fifty single-rooted freshly extracted human teeth were used. After determining the root canal length with a K-file and a dental operative microscope, the canals were measured with four separate DP ZX apex locators (two with more than 6 years of life service while two others had less than 6 years of life service). Data were analyzed by repeated ANOVA measurement. Results: No significant difference was found between the EALs with different years of life services (P=0.62). All EALs could determine root canal length with high accuracy of more than 94%. Conclusion: Based on the results of this in vitro study, the long service life had no significant impact on the accuracy of DP ZX EALs in terms of root canal length determination.

Effect of Administration of Lidocaine at Body Temperature on Anesthesia Success in Rodent Model: A Behavioral and Electrophysiology Study.

Introduction: Success in anesthesia administration relieves the perception of pain during surgery. Lidocaine is the most commonly used local anesthetic agent in clinical medicine. Moreover, anesthetic agents' temperature changes can influence cell membrane permeability. Here, the effectiveness of different temperatures of Lidocaine (Lid.) on anesthesia success rate has been investigated in rats. Methods: Wistar male rats were pretreated by fast injection of lidocaine or saline into the hind paw or intradermal cheek at Room Temperature (RT) and Body Temperature (BT) (22°C and 37°C, respectively). Then, rat behaviors were evaluated by formalin-induced hind paw pain and orofacial pain tests, respectively. Moreover, using a single-unit recording technique, the spontaneous activity of the marginal nerve was recorded at room temperature in the RT-Lid. and BT-Lid. groups. Results: Data analysis revealed that lidocaine had significant antinociceptive effects in both the BT-Lid. and RT-Lid. groups compared to the control groups (P<0.05). Also, the number of spikes in the BT-Lid. and RT-Lid. groups were significantly lower than their baselines (P<0.05). However, lidocaine at body temperature decreased the total time spent licking the hind paw, the number of lip rubbings, and the number of spikes firing by about 10%-15% compared to room temperature. Conclusion: In both behavioral and neural levels of the study, our results showed that an increase in the temperature of lidocaine toward body temperature could increase anesthesia success rate compared to administration of lidocaine at room temperature. These findings can be considered in the treatment of patients. Highlights: Lidocaine at body temperature acted better than room temperature on pain control in the formalin-induced hind paw test.Lidocaine at body temperature acted better than room temperature on pain control in the orofacial formalin test.Lidocaine with different temperatures decreased the firing rate of the marginal nerve. Plain Language Summary: Pain is defined as an unpleasant experience caused by tissue damage or fear of injury. During anesthetic injection in dentistry, pain has long been one of the problems of dentists. Studies have shown that one out of every three people is worried about going to dentistry, and one of four dental patients is afraid of injections. The fear of a patient in one of twenty patients is so much that interferes with dental treatment which consequently leads to stress when you visit the dentist, results in less oral hygiene and reduces the number of referrals. Lidocaine is the most commonly used local anesthetic agent in clinical medicine. Here, the effectiveness of different temperatures of lidocaine on anesthesia success rate in rats has been investigated in rats. The present study showed that warming the lidocaine cartridges to 37°C increased anesthesia success compared to anesthesia-induced at room temperature in both behavioral and neural levels of the study. Accordingly, a warmed anesthetic cartridge could be used to control pain by increasing the success rate during dental injection and designed a new animal model study for further investigation in comparing other anesthesia drugs.

The ability of pulp sensibility tests to evaluate the pulp status in primary teeth.

BACKGROUND. Accurate determination of the pulp status is the most important part of conservative pulp therapy. AIM. The aim of this study was to assess the ability of thermal and electrical pulp tests to assess the pulp status in primary teeth. DESIGN. Seventy-eight primary molar teeth in 36 children were investigated. Fifty-six teeth had unknown pulp status in need of endodontic treatment, and 22 were intact teeth with no signs of pulp disease. Cold, hot and electrical pulp testing (EPT) were performed on each tooth. The gold standard was established by direct inspection of the pulp after an access cavity had been made. The sensitivity, specificity, positive and negative predictive values for each test and different sequential combinations of pulp testing were calculated. Sequential combination test analysis was used for data analysis. RESULTS. The highest accuracy was found for EPT, followed by heat and cold tests. No significant difference was found between the accuracy of EPT and the heat test (P-values > 0.05); however, the accuracy of EPT was significantly higher than that of the cold test (P-value< 0.05). CONCLUSION. Based on this study, EPT can be used as a reliable test for diagnosing the pulp status in primary teeth.

Evaluating the Effect of Oblique Ridge Conservation on Stress Distribution in an Endodontically Treated Maxillary First Molar: A Finite Element Study.

INTRODUCTION: Although the maxillary first molar (MFM) has been frequently subjected to stress analysis in endodontic investigations, the available data about the effect of its oblique ridge are quite sparse. The aim of this study includes evaluating the effect of the residual oblique ridge on the stress distribution after preparing conservative access cavities. METHODS: Based on the cone-beam computed tomographic data, the model of an intact MFM and 5 cavity designs were prepared for endodontic treatment, which were consequently filled with gutta-percha and dental resin composite (6 total models). All models were subjected to 4 types of occlusal loading; finite element analysis via ABAQUS CAE software (Dassault Systemes, Vélizy-Villacoublay, France) was accomplished, whereas other software programs such as (Mimics Research Materialise, Leuven, Belgium) and 3-Matic Research (Materialise) were also incorporated in different stages for detecting stress distribution. RESULTS: The stress distribution on the MFM is not only dependent on the remaining width of the oblique ridge but also on the type of loading. The most stress on the cervical region was concentrated on the palatal root in some type of loading, whereas the least stress on the occlusal surface was recorded when the whole oblique ridge was replaced by the composite resin. CONCLUSIONS: When the occlusal contacts are occurring only on the palatal cusp, the stress distribution on the oblique ridge is noticeably affected by the cavity design.

Comparison of the Anaesthesia Success Rate in Maxillary First and Second Molars with 3% Prilocaine as the Anaesthetic Agent.

OBJECTIVE: The aim of this study was to compare the success rate of anaesthesia with 3% prilocaine and felypressin (0.03 IU/mL) in maxillary first and second molar teeth with irreversible pulpitis. METHODS: The study population was 159 patients (53 males, 106 females) who had maxillary first or second molar teeth with irreversible pulpitis (84 first molars, 75 second molars). A buccal infiltration of 3% prilocaine with 0.03 IU/mL felypressin was used as the primary anaesthetic technique. In addition to using a categorised pain score, sound, eye movement and body motion were considered signs of anaesthesia efficacy. The data were analysed with independent t and Chi-square tests. Significance was set at α=0.05. RESULTS: Overall, the success rate was 56.6% in maxillary molars, 53.6% in maxillary first molars, and 60% in maxillary second molars. There was no statistically significant difference between maxillary first and second molars in terms of anaesthesia success rate (P>0.05). The overall success rate of intraligament supplementary injections was 50%, and intrapulpal supplementary injections was 97.91%. No significant difference was found between maxillary first and second molars in terms of the success rate of the supplemental techniques (P>0.05). CONCLUSION: No significant difference was found between maxillary first and second molars in terms of anaesthesia success rate when 3% prilocaine with 0.03 IU/mL felypressin was used as an anaesthetic solution for the infiltration injection.

Repair of furcal perforation using a new endodontic cement.

The aim of this study was to compare the histologic response elicited by repairing furcal perforations with mineral trioxide aggregate (MTA) and a new endodontic material in the name of "calcium enriched mixture (CEM) cement" in dogs' teeth. Thirty-four premolars were randomly divided into four groups: MTA (n = 15), CEM (n = 15), positive, and negative controls (n = 4). Root canal therapy were carried out; perforations were made, and the furcation areas were then repaired with MTA or CEM cement. The animals were sacrificed after 3 months. The teeth and their adjacent structures were processed and stained with hematoxylin and eosin stain for histological evaluation. Chi-square test was used to evaluate hard tissue formation, and Mann-Whitney U test was used for the histological evaluation of inflammation. Specimens in positive controls showed severe inflammatory infiltration, prominent granulation tissue, and epithelial proliferation; negative controls demonstrated normal periodontal ligament without inflammatory reactions. Hard tissue formation was observed in all the specimens of the two experimental groups. In inflammatory evaluation, mild inflammation was detected in the experimental groups, and no statistically significant differences were observed between them. MTA and CEM cement showed similar favorable biological response in furcation perforation repair, especially in inducing the formation of cementum-like hard tissue.

Histological Evaluation of Human Pulp Response to Direct Pulp Capping with MTA, CEM Cement, and Biodentine.

STATEMENT OF THE PROBLEM: Direct pulp capping (DPC) is an established method in which the exposed pulp is coated with a suitable material to prevent further damage and to help its repair and healing. Different proposed materials may have different impact on pulp response during this treatment. PURPOSE: The purpose of this study was to compare the response of human dental pulp after DPC with calcium-enriched mixture (CEM), mineral trioxide aggregate (MTA) cement, and Biodentine. MATERIALS AND METHOD: In this clinical trial study, class V cavities were prepared on the buccal surfaces of 30 human premolar teeth, until the pulps were mechanically exposed. Then, teeth were randomly pulp capped with MTA, CEM cement and Biodentine, followed by resin modified glass ionomer filling. The fourth group was the control group (n= 10), in which the teeth were extracted without any prior intervention. Six weeks after the intervention, the teeth were extracted and prepared for histological evaluation in terms of the type and degree of pulp inflammation, dentin bridge formation and the presence of necrosis. Data were analyzed using Kruskal-Wallis and Mann Whitney U tests. RESULTS: In all groups, necrosis was not observed and inflammation was chronic. The Biodentine group exhibited significantly more pulpal inflammation compared with the other groups (p= 0.001). There were no significant differences among CEM cement, MTA and Biodentine in terms of the dentine bridge formation. The thickness of the dentin bridge formed in the Biodentine group was significantly higher than MTA and control group (p= 0.035 and p= 0.011, respectively). CONCLUSION: Although the dentin bridge formation and the thickness of dentin bridge formed in the Biodentine group were higher than the other groups, pulp showed greater inflammation compared to CEM cement and MTA. The results of this study suggested that MTA and CEM cement performed better when employed as the direct pulp capping material.

The Knowledge and Attitude of Diabetic Patients Regarding Oral and Dental Disorders in Kerman Diabetes Clinics.

STATEMENT OF THE PROBLEM: Diabetes mellitus is one of the most common endocrine disorders. This disease has devastating effects on many organs and tissues of the body including oral and dental tissues. PURPOSE: The aim of this study was to evaluate the knowledge and attitude of diabetic patients about dental and oral diseases. MATERIALS AND METHOD: In this cross-sectional study, 433 diabetic patients who referred to Kerman Diabetes Clinics were included. Data were collected using a questionnaire consisted of three parts of demographic characteristics, knowledge of oral and systemic complications of diabetes mellitus, and patients' attitude regarding their oral health. Data were analyzed using SPSS version 21 and employing t-test and multiple linear regression analysis. Statistically significant values were considered at p≤ 0.05. RESULTS: The mean scores for the knowledge of systemic and oral complications were 0.80±0.21 and 0.39±0.23, respectively. The mean total knowledge of diabetic patients was 0.53±0.18, and the mean score for the patients' attitude was 0.63±0.11. It was revealed that people with a family history of diabetes did not have significantly greater overall knowledge (p= 0.082). Also, people with longer disease duration (p= 0.004) and female patients (p= 0.05) had significantly a better knowledge and attitude in terms of oral health. CONCLUSION: The knowledge and attitude of patients regarding their oral and dental health and diseases were at moderate level, which should be promoted by constant planning and education according to the current needs of society.

Comparison of Pulp Sensibility Tests Responses in Type 2 Diabetes Patients and Healthy Individuals.

INTRODUCTION: Diabetes is a common disease that may have some influence on sensory nerves. The aim of this study was to evaluate dental pulp responses to 2 pulp sensibility tests (ie, cold and electric) in patients with type 2 diabetes compared with healthy individuals. METHODS: Three hundred twenty-two premolar teeth in 51 patients who had type 2 diabetes and 347 premolar teeth in 53 individuals with no medical conditions were investigated. The patients with type 2 diabetes were unified and had fasting plasma glucose <300, hemoglobin A1C <10, less than a 10-year history of diabetes mellitus, and no history of hypertension. Electric and cold pulp sensibility tests were performed for all teeth. The cold test results were recorded by the Heft-Parker visual analog scale, and the electric pulp test results were recorded based on the pulp tester's grade that evoked a response. RESULTS: There was no statistically significant difference between upper and lower premolar teeth in healthy individuals compared with the patients with diabetes in response to the cold and electric pulp tests (P > .05). In the patients with diabetes, the response of their upper premolars to the cold test was significantly reduced in diabetic patients >45 years of age (ß = -1.15, P = .013). However, there was no significant correlation between the cold test and age in the lower premolars of both diabetic and nondiabetic participants (P > .05). There was also no significant correlation between the need for a higher number of the electric pulp test current to evoke a response in maxillary and mandibular premolars of the patients with diabetes and nondiabetic participants with age (P > .05). CONCLUSIONS: There was a significant correlation between the reduction of maxillary premolar teeth responses to the cold test in diabetes patients >45 years of age.

MTA pulpotomy of human permanent molars with irreversible pulpitis.

The histological success of mineral trioxide aggregate (MTA) pulpotomy for treatment of irreversible pulpitis in human teeth as an alternative treatment was investigated in this study. Fourteen molars which had to be extracted were selected from patients 16-28 years old. The selection criteria include carious pulp exposure with a history of lingering pain. After isolation, caries removal and pulp exposure, MTA was used in pulpotomy treatment. Patients were evaluated for pain after 24 h. Two patients were lost from this study. Twelve teeth were extracted after 2 months and were assessed histologically. Recall examinations confirmed that none of the patients experienced pain after pulpotomy. Histological observation revealed that all samples had dentin bridge formation completely and that the pulps were vital and free of inflammation. Although the results favour the use of MTA as a pulpotomy material, more studies with larger samples and a longer recall period are suggested to justify the use of MTA for treatment of irreversible pulpitis in human permanent teeth.

Resolved Tooth Discolouration Following Root Fracture Employing a Conservative Approach: A Case Report.

Dental trauma is one of the most common childhood incidents that leads to the damage or loss of deciduous and permanent teeth. One of the most challenging types of dental trauma is horizontal root fracture (HRF). In this case report, a central maxillary incisor with horizontal root fracture had been treated by the conservative approach of splinting the tooth and follow-up. In the initial evaluation, the tooth had a normal appearance and did not respond to either the cold test or electric pulp tester. After 4 weeks, the tooth was sensitive to the cold test; however, showed discolouration. After 4 months, discolouration disappeared and the tooth had a positive response to pulp sensibility tests. The tooth remained asymptomatic with a positive response to pulp sensitivity tests up to 15 months following the treatment.

Effect of Various Electronic Devices on the Performance of Electronic Apex Locator.

Introduction: Apex locators are important devices that can be used to determine working length during root canal treatment. However, it is not known whether electronic devices with various wave length frequencies influence the accuracy of apex locators. The aim of this study was to determine whether a cordless phone set, MP4 player, FM radio, asymmetric digital subscriber line (ADSL), or a mobile phone could influence the accuracy of working length determination by the Dentaport ZX apex locator. Methods and Materials: In this study, twenty-four sound intact single-rooted extracted human teeth were used. After determining the root canal length with a file and a microscope, the canals were measured with three separate Dentaport ZX apex locators while one of the test devices (ADSL, MP4, FM radio, mobile phone, and cordless phone) was used at a distance of 50 cm from the apex locator. Bland-Altman plots was used for reliability and consistency. Results: Except for the FM radio, all other devices showed significant difference with actual working length (P<0.05). ADSL and MP4 player showed the least consistency compared to the other devices. Conclusion: Based on this in vitro study, the use of ADSL, MP4 player, mobile phone, and cordless phone during root canal treatment may influence working length determination with the Dentaport ZX apex locator.