In Vitro Analysis of the Fatigue Resistance of Four Single File Canal Preparation Instruments.

Instrument separation during root canal therapy is inevitable in endodontics with several unfavorable clinical consequences. Therefore, examining the cyclic flexural fatigue resistance of commonly used rotary endodontic files is crucial. This study aimed to determine the cyclic flexural fatigue resistance of four nickel-titanium (NiTi) rotary files used as a single canal preparation technique: WaveOne, Reciproc, Protaper F2, and Unicone medium instruments. According to the manufacturer's instructions, each file was rotated freely within a 1.3 mm deep and 1.3 mm wide V-shaped groove in a stainless-steel block with a 40° and 5 mm radius of curvature. Cyclic fatigue resistance was compared between the NiTi files by verifying the time needed to crack. The data were analyzed using one-way analysis of variance (ANOVA) followed by Scheffé post hoc with a significant level set at p < 0.05. Our results demonstrated that the WaveOne instrument had the highest cyclic flexural fatigue resistance among the tested groups (p ≤ 0.05), while Unicone had the lowest cyclic flexural fatigue resistance. This study concluded that WaveOne size 25/0.08 could illustrate a superior cyclic flexural fatigue resistance when instrumenting root canals with the lowest possibility to cause instrument separation.

Creation and Evaluation of an Endodontic Diagnosis Training Software.

OBJECTIVE: The purpose of the study is to evaluate a user-friendly, comprehensive, fully integrated web- and mobile-based application that was specifically developed to guide learners and help them practice and train in pulpal and periapical diagnosis. METHODS: The software was designed for assistance in the diagnosis of the pulpal and the periapical area. The software contained questions and tests, e.g., presence or absence of signs and symptoms, cold test, percussion, palpation, and radiographic examination that the user must answer to arrive at the final diagnosis. An electronic survey was prepared to evaluate the effectiveness, productivity, and accurateness of the software. The software and the electronic evaluation survey were sent by e-mail to dental students, endodontist, general dentists, and dental interns who study or work in four Saudi dental colleges. Data was analyzed using descriptive statistics. RESULT: A total of 203 questionnaires were completed. Results showed that 29% of the participants were highly satisfied with the software; 40% gave a very good rating about the application satisfaction, while only 2% reported a poor degree of satisfaction with the software. Results also showed that students accurately selected the correct diagnosis but received relatively low diagnostic proficiency scores because they did not request diagnostic data in a pattern similar to experts. CONCLUSION: In conclusion, the software is promising as an effective and efficient tool for teaching and assessing the diagnostic skills of learners.

Molecular identification and diversity analysis of dental bacteria in diabetic and non-diabetic females from Saudi Arabia.

Periodontal disease is a chronic infectious disease, which is characterized by the damaged dental hard tissue by lactic acid generated by microorganisms after the fermentation of carbohydrates rich diet. The risk of periodontal disease is known to be higher in diabetic patients. We compared the diversity of five commonly occurring dental bacteria including Porphyromonas gingivalis, Tannerella forsythia, Capnocytophaga ochracea, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans in 14 type-2 diabetic patients and equal numbers of healthy controls. The subgingival samples were collected using sterile paper points. We used 16S rRNA sequence specific primers for PCR-based identification of dental bacteria. Our results showed that A. actinomycetemcomitans was completely absent in control subjects but present in 43% of diabetic patients. C. ochracea was highly prevalent in diabetic patients (100%) as compared to controls (28.5%). The frequency of other three bacterial species was also higher in diabetic patients than control subjects. These findings indicate that dental bacteria are highly prevalent in subgingival pockets of diabetic patients. Therefore, proper monitoring of diabetic patients for dental care is important to prevent bacterial growth and its sequela in risky individuals. Further case-control studies using larger sample size would help in validating the association between oral diseases and diabetes.

Comparison of bacterial removal from dentinal tubules with different irrigant agitation techniques: An in vitro study.

AIM: This investigation was conducted to assess the ability of various irrigant agitation devices to eradicate Enterococcus faecalis from the dentinal tubules of extracted teeth. METHODOLOGY: Fifty roots of extracted human teeth were instrumented to size 30 k with a 0.04 taper. The roots were autoclaved and then injected with E. faecalis. The canals were assigned to one of four intervention groups and disinfected using (A) standard needle irrigation, (B) EndoUltra® Ultrasonic Activator, (C) the EndoActivator system, or (D) EDDY sonic activation and to two control groups that were (E) treated with saline and (F) not inoculated with any bacteria. The roots were split in half, dyed with a LIVE/DEAD Back Light Bacterial Viability Kit, and then scanned with a confocal laser scanning microscope (CLSM) to identify live/dead bacteria in the dentinal tubules. RESULTS: CLSM images revealed differences among the groups. Both the EndoUltra® Ultrasonic Activator group and the EDDY group had a combination of dead and live bacteria, while the EndoActivator group had mostly dead bacteria, in contrast to single needle irrigation which had mostly live bacteria. Activation of the irrigating solution resulted in more dead bacteria than standard needle irrigation at the coronal, middle, and apical parts of the roots. Overall, the EndoActivator system was superior to all other techniques in reducing live bacteria within the root canal. CONCLUSION: Activation of sodium hypochlorite with sonic and ultrasonic systems dramatically reduced live bacteria contamination in the dentinal tubules of infected root canals.

Comparison of perceived pain and patients' satisfaction with traditional local anesthesia and single tooth anesthesia: A randomized clinical trial.

BACKGROUND: Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients. Since the introduction of Computer-Controlled Local Anesthetic Delivery Systems to dentistry, many studies have compared its efficacy and safety to conventional anesthesia. However, very few studies have compared single tooth anesthesia (STA) and traditional local anesthesia. AIM: To compare pain rating, changes in blood pressure, and heart rate during the local anesthetic injection. The secondary objectives were to measure the patients' level of satisfaction and the differences in anesthetic efficiency between the STA system and traditional local infiltration. METHODS: A randomized controlled trial was conducted and a total of 80 patients with dental restorative needs were enrolled for the study. The patients were evaluated for their general physical status and oral clinical findings before enrollment. Information regarding perceived pain, changes in heart rate and blood pressure, and patients' satisfaction was collected using an electronic data form and was analyzed using paired and unpaired t-tests. RESULTS: No significant difference was noted in perceived pain (P = 0.59) and systolic blood pressure (P = 0.09) during anesthetic injection using both traditional and STA techniques. STA patients had a significantly higher heart rate during anesthesia, although a statistically significant difference was noted among the traditional anesthesia and the STA groups even before anesthesia. During the restorative procedure, less pain was perceived by STA patients on the Wong-Baker FACES pain scale, which was statistically significant (P < 0.001). Analyses of post-procedure patient responses showed that STA patients had a significantly better treatment experience and preferred to have the same method of injection in the future (P = 0.04). CONCLUSION: STA system can provide less painful and more comfortable restorative treatment procedures in comparison to the traditional infiltration technique.

Comparison of Cyclic Fatigue Resistance of 5 Heat-treated Nickel-titanium Reciprocating Systems in Canals with Single and Double Curvatures.

INTRODUCTION: The goal of this study was to compare the cyclic fatigue resistance of 5 heat-treated nickel-titanium files in reciprocating movement with the same tip size and different cross sections. METHODS: Five groups (WaveOne [Dentsply, Ballaigues, Switzerland], WaveOne GOLD [Dentsply], RECIPROC [VDW, Munich, Germany], RECIPROC BLUE [VDW GmbH, Munich, Germany], and TF [Sybron Endo, Glendora, CA] Adaptive) of 24 files each of the rotary files were examined. Cyclic fatigue resistance was compared between groups by determining the time needed to fracture and the number of cycles to failure in a cyclic fatigue testing device with 2 different curvatures, the first with a 5-mm radius of curvature and a 60° angle and the second with a double curvature, coronal curvature of 60° angle and a radius of 5 mm, and an apical curvature of 70° angle and a 2-mm radius. Scanning electron microscopic evaluation was performed at the fracture sites to investigate the types of fracture. RESULTS: RECIPROC BLUE group had a higher mean time to fracture followed by RECIPROC and WaveOne GOLD for both single and double curvature. WaveOne had a higher mean time to fracture in a single curvature canal than TF Adaptive, whereas the opposite was true for a double curvature canal. Both RECIPROC groups were significantly greater in cyclic fatigue resistance in comparison with all other groups (P < .05). WaveOne GOLD was significantly greater than the WaveOne and TF Adaptive groups (P < .05). CONCLUSIONS: RECIPROC BLUE files exhibited significantly greater cyclic fatigue resistance compared with other files tested in an S-shaped artificial canal.

Comparison of the Antibacterial Efficacy of Commiphora molmol and Sodium Hypochlorite as Root Canal Irrigants against Enterococcus faecalis and Fusobacterium nucleatum.

OBJECTIVE: The investigation aims to compare antimicrobial efficacy of the extract of Commiphora molmol, against Enterococcus faecalis and Fusobacterium nucleatum, with sodium hypochlorite (NaOCl). DESIGN: T he dehydrated oleo-gum resin of Commiphora molmol was extracted by using 70% ethanol and was suspended in 99.8% dimethyl sulfoxide (DMSO) as a dissolving agent in a 1:2 volume to produce an aqueous solution at room temperature. Agar-well diffusion and broth microdilution methods assay were utilized to determine both the antimicrobial activity and minimum inhibitory concentration, of alcoholic extract of Commiphora molmol against E. faecalis and F. nucleatum. The values of the inhibition zones were determined based on the concentration of the investigated material. One hundred and forty extracted human premolar teeth were instrumented and immersed in bacterial suspension of E. faecalis or F. nucleatum (70 teeth in each species suspension). Prepared teeth were then immersed in the myrrh extract solution, 2.5% NaOCl, DMSO, or Cefotaxime and incubated for 30 and 60 minutes. RESULTS: The largest inhibition zone diameter for both bacterial species was obtained by the 100mg/100µL concentration. The minimum inhibitory concentration (MIC) was 0.03mg/300µL for both E. faecalis and F. nucleatum. The minimum bactericidal concentration (MBC) results showed that 0.03mg/µL myrrh extract and 2.5% sodium hypochlorite significantly reduced bacterial growth at both 30 and 60 minutes of different treatments of root canals, compared to DMSO group (negative control) and the antibiotic group (positive group). CONCLUSION: Myrrh extract was proven to have considerable antibacterial activity against both F. nucleatum and E. faecalis.

Cutaneous draining sinus tract of odontogenic origin. A case of chronic misdiagnosis.

This is a case of a patient with a buccal cutaneous sinus tract, originally misdiagnosed, with delayed healing and potential malpractice. An odontogenic cutaneous sinus tract is a pathologic canal that initiates in the oral cavity but opens externally at the cutaneous surface of the face or neck. It is frequently misdiagnosed, leading to inappropriate treatment. Once correct diagnosis is made, definitive treatment, through oral therapy to eliminate the source of infection, is simple and effective. This case was initially misdiagnosed as a sebaceous cyst and laceration of parotid gland. The case was correctly diagnosed through detailed examination and evaluation, using tracing and advanced imaging technology (cone beam imaging). Endodontic treatment was performed, which resulted in rapid resolution of the case, followed by dermatologic treatment with fractional laser to treat the scar formed.

Effectiveness of a 20% Miswak extract against a mixture of Candida albicans and Enterococcus faecalis.

OBJECTIVE: To examine the in vitro antimicrobial effect of a 20% Miswak extract against a mixture of Candida albicans (C. albicans) and Enterococcus faecalis (E. faecalis) using the dilution tube susceptibility test, which allows direct contact between the tested material and the microorganisms. METHODS: The study samples were collected and processed between August 2009 and January 2010 in the College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Each microorganism was obtained in a suspension and exposed to a 20% Miswak extract in plastic tissue culture clusters containing 24 wells. Six wells were used per group. The Miswak extract was incubated with the microorganisms for one, 6, and 24 hours. RESULTS: This in vitro study showed that Miswak extract was an effective antifungal and antibacterial agent at all tested experimental time periods, except one hour exposure of a 20% Miswak extract to E. faecalis and a mixture of E. faecalis and C. albicans, which was ineffective in inhibiting their growth. CONCLUSION: Twenty percent Miswak extract is an effective antifungal and antibacterial agent against C. albicans and E. faecalis.