The purpose of this study was to evaluate the combined effect of ferrule height and post length on fracture resistance and failure mode of endodontically treated teeth restored with glass fibre posts, composite resin cores and crowns. Ninety human maxillary central incisors were endodontically treated and divided into three groups (n = 30) according to the ferrule heights: 4, 2 and 0 mm, respectively. Post spaces in each group were prepared at 2/3, 1/2 and 1/3 of the root length (n = 10). The specimens were received fibre posts, composite resin core build up and cast metal crowns. After thermocycling, compressive static load was applied at an angle of 135° to the crowns. Two-way analysis of variance showed significant differences in the failure load in the ferrule height groups, no significant differences in post length groups and no significant interaction between ferrule heights and post lengths. More restorable failure modes were observed.
The aim of this study was to evaluate the antimicrobial activity of a new experimental nano-hydroxyapatite epoxy resin-based sealer (Nanoseal) with several other commercially available sealers; AH26, Tubliseal, Sealapex and Roekoseal against Enterococcus faecalis, Pseudomonas aeruginosa, Streptococcus mutans, Streptococcus sobrinus and Escherichia coli for up to 7 days. Agar diffusion was used in this study. Fifty Muller-Hinton agar plates were prepared and divided into five experimental groups (n = 10), for each micro-organism. Another 10 agar plates were used as positive and negative controls. Endodontic sealers were tested against each micro-organism. Inhibition zones produced were recorded. The results of this study showed that all test materials exhibited inhibition zones towards the tested micro-organisms for 7 days except for Roekoseal, which showed no inhibition zones. Nanoseal and AH26 exhibited similar zones of inhibition. Significant difference was found between Nanoseal and the other tested sealers (P < 0.001).
The aim of this study was to evaluate in vitro the apical sealing ability of cold lateral and system B root filling techniques using dye penetration. Eighty-six extracted single-rooted human teeth were prepared and randomly divided into two experimental groups to be obturated by cold lateral condensation (n = 33) and system B (n = 33). The remaining 20 teeth served as positive and negative controls. The roots were embedded for 72 h in methylene blue dye solution and sectioned transversely for dye penetration evaluation using stereomicroscope. The results of this study showed that cold lateral condensation leaked significantly more (P < 0.001) than system B technique.
This study aimed to assess regenerative treatment protocols for maturogenesis of immature teeth with apical periodontitis in dogs. Apical periodontitis was induced in immature premolars of 8 mongrel dogs teeth that were divided into 5 groups; regeneration via blood clotting (REG group); chitosan loaded with demineralised bone matrix (REG-CD group); chitosan loaded with dexamethazone corticosteroid (REG-CC group); and positive and negative control groups. All groups showed comparable apical hard tissue formation and significantly different from the control group. Results also showed decrease in inflammatory tissue reaction, bone resorption and periodontal ligament thickness. Tissue reaction and inflammatory infiltrates were significantly less in REG-CC group compared to others. Other parameters showed no significant difference. In conclusion, regenerative endodontic techniques using chitosan-based formulations have the potential to be used as an alternative for root maturation in teeth with apical periodontitis.
This cone beam computed tomography (CBCT) study aimed to evaluate the root canal morphology of permanent anteriors in Malaysian population using two classification systems (Vertucci 1984 and Ahmed et al 2017). CBCT images of 856 patients with 10,080 anterior teeth were analysed. Results showed that, except for six mandibular canines, all anterior teeth were single-rooted. According to Ahmed et al's system and Vertucci's classification, code 1 MaxA1 and type I were the most common types except in mandibular laterals where 1 ManA1-2-1 and type III were the most common, respectively. The prevalence of canal variations in mandibular incisors was higher in males and the 20-30 age group than in females and other age groups (P
In endodontic infections, inflammatory mediators such as cytokines are released, recruited and retained until the infection is eradicated. Root canal therapy is performed to prevent the spread of infection. The aim of this study was to investigate the effects of root canal debridement (cleaning and shaping) on periapical inflammation by measuring the levels of inflammatory cytokines, Interleukin-8 (IL-8) and Interleukin-10 (IL-10). The study includes twenty patients with pulp necrosis and asymptomatic apical periodontitis. Periradicular sample was collected using paper points before and after root canal debridement. Cytokine levels were determined by Sandwich Enzyme-Linked Immunosorbent Assay (ELISA). Data were analysed using paired t-test (PASW Statistics 18) (P = 0.05). All samples showed the presence of IL-8 and IL-10 prior to root canal debridement. Significantly reduced levels (P < 0.05) of IL-8 and IL-10 were detected after root canal debridement. In conclusion, root canal debridement significantly decreased the levels of the tested pro- and anti-inflammatory cytokine in the periradicular interstitial fluid.
This systematic review assessed the effect of different root canal instrumentation systems on endotoxin reduction from the root canal system. The literature search was conducted in two electronic databases (PubMed and Scopus) using specific key words. The search strategy followed the PRISMA guidelines. Qualitative synthesis and quantitative synthesis of the data were performed and data interpretation was done based on the guidelines in the Cochrane Handbook. The risk of bias was assessed using Cochrane criteria. The initial search yielded 600 citations, of which three papers met the criteria for inclusion in this review. Studies showed a significant reduction in endotoxin following rotary and reciprocating instrumentation, with no significant differences between them. The meta-analysis showed no statistical significant difference between reciprocation and rotary files (P > 0.05). In conclusion, the instrumentation techniques compared in this review decrease endotoxin content from root canals, with no significant difference between them.
This study aimed to determine the difficulty level of extracted teeth treated by undergraduate students for pre-clinical endodontic training. Two independent observers assessed a consecutive sample of 1000 periapical radiographs of extracted teeth used in endodontic pre-clinical training. Chi-square test was used to evaluate the adjustment of the distribution, and inter- and intra-examiner agreement were calculated. Minimal, moderate and high difficulty teeth represented 23.1%, 52.1% and 24.8%, respectively. The presence of curvature was the most common grading factor, with 'moderate curvature' reported in 28.7%, and 'extreme curvature' reported in 15.6% of the sample. A difference in the distribution of frequencies was found, favouring the moderate category (P
This study aimed to evaluate and compare the frequency of microcracks and its severity at different root canal dentin locations, after preparation with thermomechanically heat-treated engine-driven nickel-titanium instruments. Forty mandibular premolars were assigned to four experimental groups (n = 10): ProTaper Next, ProTaper Gold, WaveOne Gold and Reciproc Blue. After pre-instrumentation micro-computed tomography scans, the root canals were prepared to size 25. Following post-instrumentation scans, pre- and post-instrumentation scanned images were analysed for the presence and extent of dentinal defects. A total of 56 500 cross-sectional images were obtained, showing that less than 2.3% with pre-existing dentinal microcracks. No new microcracks were identified during the post-instrumentation analyses. No significant association was found between the types of dentinal defects, file motions and sequences. Thermomechanically heat-treated rotary files did not induce the formation of new microcracks. There was also no association between the kinematic motions and sequences of the rotary instruments to the types of dentinal defects.
This review aims to evaluate the antimicrobial efficacy of calcium hydroxide against endodontic pathogens when used for 7 days or longer. A systematic electronic literature search was performed in the PubMed, Embase and EBSCO Dentistry & Oral Sciences Source databases using appropriate key words to identify investigations written in the English language that examined the association between the contact time of intracanal calcium hydroxide dressing and its antimicrobial properties. There were no exclusions based on study design. The search yielded 6993 publications. After duplicate removal, 5913 publications were identified and 11 studies met the inclusion criteria. Results showed that the antimicrobial effect of calcium hydroxide for contact times ranging between seven and 45 days is comparable. Two studies demonstrated contradictory findings when exposure was extended to more than 45 days. Future studies are warranted to investigate and optimise calcium hydroxide application for longer periods and identify the potential benefits of its use in clinical settings.
This study aimed to determine the incidence and contributing factors to pulpal and periapical disease in crowned vital teeth. Seventy-three pairs of healthy teeth were included and divided into two groups; 'crowned' and 'untreated' groups. The crowned group was prepared for full coverage crown and no treatment was carried out on the untreated group. Both groups were subjected to clinical and radiographic examination to detect endodontic signs and symptoms pre-operatively and one-week after crown cementation. Electric pulp test was also subjected to both groups, pre-operatively, after tooth preparation and before crown cementation. The incidence of pulpal and periapical disease was 6.8% and 1.4%, respectively, after tooth preparation. Factors associated with pulpal and periapical disease were exposed pulp during tooth preparation and pre-operative bone level <35%. Despite the low incidence, the occurrence of pulpal and periapical disease within a short period is noteworthy.
This review investigated whether any therapeutic options influenced the outcome of treatment for teeth with external cervical resorption. Out of 870 articles identified by an electronic search, 60 clinical case reports and six case series were included. No randomised clinical trials were found. Risk of bias was assessed using Joanna Briggs Institute's tools. External surgical intervention was the preferred method of accessing the lesions. Removal of resorptive tissue was prevalently achieved mechanically. Bioactive endodontic cements were the preferred materials for restoring teeth. The outcome measures were based on clinical and radiographic parameters. Of the cases included in the review, no specific treatment approach had a superior outcome in relation to Heithersay's classification. Furthermore, due to the absence of randomised clinical trials, and to the low level of evidence associated with case reports/case series, it was not possible to define the optimum clinical treatment for external cervical resorption.
A novel system to classify root and canal morphology was recently introduced (Ahmed et al. 2017). This systematic review aimed to answer the following research question: Does the Ahmed et al. system provide a more accurate and practical classification of root and canal anatomy compared to other classifications? A literature search was conducted in Google Scholar, Scopus and Wiley Online Library to identify the citation counts for the article entitled 'A new system for classifying root and root canal morphology; doi.org/10.1111/iej.12685'. After removal of duplicates and unrelated articles, 15 studies were included and analysed. All studies compared the Ahmed et al. system with the Vertucci classification. Results revealed that both systems were able to classify simple canal configurations in single-rooted anterior and premolar teeth, disto-buccal and palatal roots of maxillary molars. However, the Ahmed et al. system provided more accurate and comprehensive categorisations of single-rooted teeth with complex canal anatomy, multi-rooted maxillary and mandibular premolars and the mesio-buccal root of maxillary molars. Further evidence on the utility of the Ahmed et al. system is required using other diagnostic devices especially in molars.
This report presents the detection, characterisation, instrumentation and filling of complex canal configurations in the mesiobuccal (MB) root of maxillary first molars. Three patients were referred for root canal treatment in first maxillary molars. Medical history, age, sex and clinical findings were recorded. Intraoral periapical radiographs and cone beam computed tomography (CBCT) were used for diagnosis and pre-operative assessment. Using Ahmed et al. (2017) classification system, codes 3MaxM MB3-5-4-2 DB1-2-1 P1 (case 1), 3MaxM MB2-5-3-2 DB1 P1 (case 2) and 3MaxM MB1-4-2-1-2 DB1 P1 (case 3) were identified. Using the dental operating microscope, CBCT (if indicated) and troughing up to 3 mm allowed identification of more than three canals in the MB root of maxillary first molars. The coding system proposed by Ahmed et al. (2017) allows the classification of MB roots with highly complex canal configurations.
The purpose of this systematic review was to assess the effect of occlusal reduction on post-operative pain following root canal treatment and was performed in accordance with the PRISMA statement being registered in the PROSPERO database (CRD42018089941). Two reviewers independently conducted a systematic literature search in the PubMed (MEDLINE), Dentistry & Oral Sciences Source and the Cochrane Library databases. Seven studies were included, of which three were used to perform meta-analysis for 6 days post-operative and the rest for qualitative synthesis. Three studies were assessed as low risk of bias, three as some concern, and one as high risk of bias. Occlusal reduction diminishes the post-operative pain (SMD -1.10 (95%CI -2.06, -0.15) I2 = 96.9%) at 6 days for teeth diagnosed as irreversible pulpitis, and, overall, likely reduces post-operative pain for patients presenting with irreversible pulpitis and/or symptomatic apical periodontitis. Future high-quality clinical trials are needed to better understand the role of occlusal reduction.