Iranian Endodontic Journal
Volume:14 Issue: 2, Spring 2019

The failure rate of inferior alveolar nerve (IAN) block is high for mandibular molars with irreversible pulpitis. This double-blind, randomized, clinical trial aimed to assess the effect of topical application of Dentol drop on the rate of successful anaesthesia of mandibular molars with irreversible pulpitis due to deep carious lesions.  Seventy-two patients with mandibular first and second molars with irreversible pulpitis and deep cavitated carious lesions participated in this study. The patients were randomly assigned to the test and control groups (n=36). In the test group, a cotton pellet, dipped in Dentol drop, was placed in the cavity for 10 min. A placebo was used _in the same manner_ in the control group. Level of pain was measured before the intervention, 15 min after anaesthesia (when patients reported numbness at the corner of the mouth), during access cavity preparation, upon pulp exposure and after introduction of the initial file into the root canal; using a Heft-Parker “Visual Analog Scale” (VAS). Data were analysed using ANCOVA. Levels of pain were recorded during access cavity preparation (P<0.001), pulp exposure (P<0.001) and file introduction into the canal (P=0.018). In the test (Dentol) group, the obtained levels of pain were significantly lower than those of the corresponding values in the control group. Topical application of Dentol drop increased the success rate of IAN block for root canal treatment of mandibular molars with irreversible pulpitis.

This study aimed to evaluate the effects of acetaminophen and ibuprofen on pulpal anaesthesia immediately after pulpectomy of primary maxillary molars. In this placebo-controlled, double-blind clinical trial, 60 children (aged 5 to 9) were referred to the Department of Pediatric Dentistry, Yazd Dental School; for primary maxillary molar pulpectomy. Local anaesthesia and analgesic drugs were used for the pre-operative stage. A five-face scale was considered to evaluate pain reaction during the pulp therapy. Pain scores were determined when the dental procedure was complete. The Kruskal-Wallis and Mann-Whitney U tests were finally used at the confidence level of 95%. Use of analgesics before pulpectomy in children can reduce pain score compared to placebo group (P<0.001) and increase the effectiveness of pulpal anesthesia. Additionally, ibuprofen exhibited lower pain scores compared to acetaminophen although the difference was not statistically significant. Pre-operative use of ibuprofen and acetaminophen might be a useful way to achieve analgesia during pulpectomy of primary maxillary molars in children.

The objective of this study was to evaluate the effects of short term intracanal medicaments on the fracture resistance of root in simulated necrotic immature teeth in pulp revitalization procedure. Bovine teeth (n=180) were selected, sectioned coronally and apically and then, internally fragilized. Intracanal medicament groups were arranged as follows: “Triple Antibiotic Paste” (TAP) group (n=60), “Calcium Hydroxide” (CH) group (n=60) and the control group (n=60). No medication was used in the control group. Fracture resistance tests were performed after 7, 14, and 21 days. At allocated intervals, 20 teeth from each group had fractured. The Kruskal-Wallis and Mann-Whitney tests were performed to verify the effects of the employed medicaments at each time point. Friedman test and Wilcoxon signed-rank test were also performed to verify the association between time and fracture resistance. The level of significance was set at 0.05. After 7 days, there was no statistical difference between groups (P=0.376). Intragroup analysis revealed that, after 21 days, the TAP group (P=0.015) and the CH group (P=0.006) presented a statically significant reduction in fracture resistance comparison with 7 days. Statistical difference was not verified for the control group after 7, 14 and 21 days (P=0.25). There was no statistical difference between CH group and the control group after 7, 14 and 21 days (P>0.05). The reduction was significant for TAP after 14 and 21 days (P=0.018, P=0.033 Respectively). This in vitro study showed that the duration at which TAP and CH remained in the root canal influenced the fracture resistance of bovine teeth with simulated incomplete root formation.

The aim of the present study was to compare the efficacy of four NiTi instruments with different properties (shape memory and control memory), in both rotary and reciprocating motions, during retreatment procedures. Mesial canals of thirty-two mandibular molars were instrumented, obturated, and then scanned with” Cone-beam Computed Tomography” (CBCT). Teeth were randomly divided into 4 groups (n=8) according to each system: “Shape Memory” (SM) instruments including Reciproc (R25 file) and ProTaper Next (X3 and X2 file), “Controlled Memory” (CM) instruments including WaveOne Gold (Primary file) and Hyflex (30.06 and 25.06 file). The specimens were rescanned after retreatment procedures. The volume of the residual material left inside the canals, the operating time and the fractured files were analyzed. ANOVA and student t-tests were used for statistical analysis. There were no significant differences in the percentage of the residual filling material or requiring time amongst different groups of instruments (P>0.05). However, CM instruments presented the highest frequency of fractured files [2 SM instruments (12.5%) and 7 CM instruments (43.75%)] with a significant difference (P=0.023). This ex vivo study showed that CM and SM instruments can remove filling materials from mandibular mesial root canals during retreatment procedures; nonetheless the CM instruments had a higher frequency of fractured files. No system was able to completely remove the filling materials. Therefore, additional procedures and techniques are needed to improve root canal cleanliness.

The aim of this study was to evaluate the effect of a new imidazolium-based silver nanoparticle (ImSNP) root canal irrigant on the bond strength of AH-Plus sealer to root canal dentine. Forty single-rooted extracted human teeth were used in this study. The crowns were resected and according to the irrigation solutions used during root canal preparation, the roots were divided into 5 groups (n=8): Group 1: normal saline (control group), Group 2: 2.5% Sodium Hypochlorite (NaOCl), Group 3: 2.5% NaOCl+17% ethylene diamin tetracetic acid (EDTA), Group 4: silver nanoparticles (AgNPs), Group 5: AgNPs +17% EDTA. After root canal instrumentation, the canals were filled with AH-Plus. Then, after 7 days, 2 or 3 dentine disks were obtained from the mid-root of each sample. Bond strength was measured by the push-out test. Additionally, failure patterns were classified as adhesive, cohesive and mixed. Data were statistically analyzed by one-way ANOVA and Tamhane post hoc tests. The level of significance was set at 0.05. There was no statistically significant differences between groups (P>0.05). Groups 4 (AgNPs), 3 (2.5% NaOCl+17% EDTA) and 2 (2.5% NaOCl) showed statistically higher bond strength compared to group 1 (control group) (P<0.05). Also, Group 4 showed a significant difference with group 5 (AgNPs+17% EDTA) (P=0.017). The failure patterns were mainly cohesive. This in vitro study showed that, when used without EDTA, AgNPs improved the bond strength of AH-Plus to radicular dentine.

This in vitro study aimed to evaluate the chemical composition, water solubility, radiopacity, pH, electrical conductivity and cytotoxicity of four different root canal sealers. Four materials were tested including an epoxy resin-based sealer (AH-Plus), a calcium silicate-based sealer (MTA Fillapex), a calcium hydroxide-based sealer (Sealapex) and a zinc-oxide-eugenol-based sealer (Endofill). The materials were submitted to energy-dispersive x-ray microanalysis for elemental chemical composition. Solubility and radiopacity were evaluated according to ANSI/ADA. The pH and electrical conductivity were measured at different periods of time. L929 immortalized mouse fibroblast line were used for cytotoxicity evaluation. Statistical analyses were carried out using the ANOVA and Tukey’s test. The main elements were found to be silicon and calcium in MTA Fillapex, calcium and bismuth in Sealapex, zirconium and tungsten in AH-Plus and zinc and bismuth in Endofill. Sealapex had the highest value for solubility (P<0.05), AH-Plus showed the highest radiopacity value (P<0.05) while MTA Fillapex had the highest pH and electrical conductivity values (P<0.05). AH-Plus showed the highest rate of cell viability (P<0.05). Based on the results of this in vitro study, it was possible to conclude that Endofill and Sealpex did not meet the requirements for water solubility. The tested sealers were alkaline and showed radiopacity in accordance with ANSI/ADA standards. AH-Plus showed to be less cytotoxic than other tested root canal sealers.

This study evaluated the occurrence of morphological changes on the surface of the instruments WaveOne™ and Reciproc® when used in the preparation of simulated curved canals with and without glide path (generated with the Pathfile™ system), after the first, second, and third uses. Sixty-four resin blocks, which simulated curved root canals, were used and instrumented with a variety of instruments, grouped according to manufacturer and conditions of simulated canal preparation. Simulated canals were instrumented with WaveOne™ (GW1 group) and Reciproc® (GR1 group) according to manufacturers’ recommendations, respectively. In contrast, GW2 and GR2 groups’ simulated canals were submitted for construction of glide path with the PathFile™ system before the use of WaveOne™ and Reciproc® instruments, respectively. Each instrument was used three times; after each use, each instrument was analyzed by using scanning electron microscopy (cervical, middle, and apical thirds of the instrument) in order to characterize the occurrence of changes (fracture, twist, and crack). Data were described using means and standard deviations. We used generalized linear models to compare differences between factors (region, manufacturer, glide path, and number of uses). SPSS-15 software was used, with a significance level of 5%. Without glide path, WaveOne™ instruments tended to fracture more frequently (P=0.003), twist more frequently (P=0.05), and crack more frequently (P=0.022), with increasing use, with statistically significant differences. With glide path, both WaveOne™ and Reciproc® instruments cracked less frequently (P=0.001); Reciproc® instruments did not exhibit superficial changes, such as fractures and/or twists. In this in vitro study Reciproc® instruments exhibited superior performance, compared with WaveOne™ instruments, particularly when glide path with the PathFile™ system was used; both instruments may be used, safely, three times to prepare curved canals.

Sodium hypochlorite (NaOCl) is extensively used in root canal treatment and its efficacy depends on the concentration of free available chlorine (FAC). This study aimed to assess the chlorine content of 10 domestically manufactured household bleach products available in the Iranian market and evaluate the effect of temperature, time and daily bottle uncapping on FAC concentration and pH of these products. One-liter bottles of 10 available brands of household bleach (n=4 of each brand) were collected and randomly divided into four groups (n=10). Two groups were refrigerated at 4°C while the remaining two were stored at room temperature. One group of refrigerated and one group of room temperature samples were subjected to daily bottle uncapping followed by agitation and recapping for 3 months (six times a week to simulate weekly office work). The remaining bottles remained untouched and served as controls. The concentration of FAC in each sample was measured using the iodometric titration assay, and the pH was measured using a calibrated pH-meter at baseline and 1, 2 and 3 months. The results were analyzed using the one-way ANOVA and t-test. The mean concentration of FAC in the solutions was 4.87±0.19% at baseline. The measured concentration of sodium hypochlorite was different from the labeled value. The concentration of FAC decreased over time in all samples; the greatest reduction occurred in room temperature samples subjected to daily uncapping while the smallest reduction occurred in refrigerated, capped bottles (19% and 1.9%, respectively). The pH of all products decreased over time. The mean reduction in pH was 1.1 for the samples stored at room temperature for 3 months and 0.8 for the refrigerated samples. This in vitro study showed that the expected concentration of sodium hypochlorite solution made of household bleach for endodontic purposes is different from its actual concentration.

This study aimed to evaluate the long-term clinical success of the use of mineral trioxide aggregate (MTA) as root canal sealer in root perforation treatments. Therefore, the dental records of 53 patients were analyzed, and treatment data was collected (age, gender, tooth location, jaw, presence or absence of radiolucent lesion, fallow up time and final radiographic/clinical assessment). All procedures were performed by a single specialist. Two examiners analyzed three radiographs from the records of each patient and classified the treatments as successful or unsuccessful. Data was analyzed statistically using parametric chi-square (P≤0.05). The examiners classified 69.8% of the cases as successful, with a follow-up time of 1-16.25 years (average: 6 years). The presence of initial radiolucent lesion was observed in 79.2% of the teeth, with a higher index of treatment in maxillary teeth (62.3%). However, the majority of successful cases were located in the maxilla (73.0%), while most unsuccessful ones were located in the mandible (62.5%) (P=0.014). There was no statistically significant difference regarding presence of previous lesions in successful (75.7%) and unsuccessful cases (87.5%) (P=0.330). In the present study, root perforations sealed with MTA had a success rate of 69.8% within 1-16.25 years. The presence of initial injury did not influence the prognosis, and maxillary teeth presented a higher success rate.

This report describes anatomical variations in an indigenous patient from the Brazilian Amazon. A 13-year-old indigenous girl attended the dental clinic for a routine examination. Clinically, a change in the coronary morphology of all upper incisors was observed; characterized by a shovel-shaped lingual surface-a feature considered a polygenic hereditary trait commonly found in native American people. The x-ray examination revealed the presence of a root anomaly in the left upper central incisor. A cone-beam computed tomography (CBCT) scan was performed, revealing the presence of a supernumerary root located on the lingual surface. A single wide canal, which bifurcated in the middle-third level into two canals with different foramina, was observed in the cervical portion. It is essential for dental surgeons to be aware of possible anatomical differences, especially considering the origin of the patient, to avoid interference in treatment success.

One of the potential serious complications, associated with the inter-radicular placement of an orthodontic miniscrew, is root injury. This article reports the endodontic and surgical treatments of an iatrogenic root perforation in a mandibular first molar caused by the placement of an orthodontic miniscrew anchorage. The 24-month follow-up showed a successful treatment outcome.

This article presents a case of odontogenic Keratocyst (OKC) located in the mandible, involving teeth 36 to 45, with significant loss of alveolar bone and aseptic pulp necrosis, emphasizing on root canal treatment after surgical intervention. Orthopantomogram and computed tomography examinations revealed an extensive, well-defined, and multilocular radiolucent lesion. Histopathological examination after incisional biopsy confirmed OKC, which was removed completely with enucleation and curettage, followed by the endodontic treatments of teeth 36 to 45 using reciprocating nickel-titanium files (Reciproc) in a single session. Afterwards, teeth 33 to 36 underwent apical surgery to create an appropriate bone development. Panoramic radiographic images showed bone formation and no sign of recurrence after one-year follow-up. In conclusion, this surgical approach, combined with the endodontic treatments of the teeth involved in the lesion, was effective for the management of OKC, promoting injury regression and preservation of the natural teeth.

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.