Outcome of single-visit root canal treatment with or without MTAD: A randomized controlled clinical trial.

AIM: This study aimed to investigate 2-year changes in periapical trabecular patterns in single-rooted teeth with apical periodontitis using fractal analysis and periapical index (PAI) after root canal treatment performed with or without BioPure MTAD solution. METHODOLOGY: In this randomized clinical trial, 100 patients were selected and randomized to either the BioPure MTAD or the control groups. Initial periapical radiographs were obtained for each participant before and 2 years after root canal treatment. The region of interest in the periapical lesion around the root apex was selected from the paired periapical radiographs, and then, the fractal dimension (FD) was calculated. With regards to the classification of periapical status, PAI was labelled as "healed" (PAI ≤ 2) or "unhealed" (PAI ≥ 3). RESULTS: After 24 months, 28 patients did not comply with the follow-up and the data of 72 patients were compared. When the initial and the follow-up PAI scores were compared, the decrease was statistically significant in 33 of 37 teeth (89.2%) and 32 of 35 teeth (91.4%) in the BioPure MTAD and control group, respectively. In both groups, statistically significant increases were observed in FD values after 2 years in all patients (p < .001). No significant difference was found between the two groups amongst decreased PAI scores and increased FD values. CONCLUSIONS: Root canal treatments with or without BioPure MTAD irrigation contributed to periapical healing in single-visit root canal treatment. Two years after root canal treatment, the extent of the periapical trabecular bone radiographically increased, as the FD and PAI data revealed.

Calcium hypochlorite on mouse embryonic fibroblast cells (NIH3T3) in vitro cytotoxicity and genotoxicity: MTT and comet assay.

Antimicrobial irrigation solutions are widely used under clinical settings. Their effect on dental tissue is a subject of recent research, which aims for a safer irrigant for clinical use. In this regard, here our goal was to evaluate the cytotoxicity and the genotoxicity of calcium hypochlorite (Ca(OCl)2) solution, along with NaOCl, on Mouse embryonic fibroblast cells (NIH3T3). First, Cells were treated either with NaOCl or Ca(OCl)2 in a time- and dose-dependent manner for cytotoxicity by 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, then cell viability was calculated according to cell proliferation plots. Secondly, genotoxicity was assessed by Comet assay. Data were statistically analyzed by Tukey's test (P < .05). NaOCl and Ca(OCl)2 had similar effects on cellular viability at 3 and 6 h treatments. Cell viability of Ca(OCl)2 at concentrations of 0.0125%, 0.025%, 0.05%, or 0.125% was significantly lower than that of NaOCl at 24 h treatment (P < .05).Comparing Ca(OCl)2 and NaOCl treatments at all time points and concentrations, the damaged cell number of Ca(OCl)2 was almost fourfold higher than that of NaOCl. In conclusion, both, NaOCl and Ca(OCl)2 solutions were cytotoxic and genotoxic to NIH3T3, however, Ca(OCl)2 had a significantly higher damaged cell percentage than NaOCl at all time points and concentrations investigated.

Post-obturation pain following the use of carrier-based system with AH Plus or iRoot SP sealers: a randomized controlled clinical trial.

OBJECTIVES: The aim of this study was to compare the postoperative pain after root canal treatment using a carrier-based obturation system and two different sealers. MATERIALS AND METHODS: In this prospective randomized clinical trial, 160 patients were selected. Patients with vital and devital teeth were randomized into four groups using a randomized block design with block sizes of 10 patients each. The groups were devital/vital teeth treated with iRoot SP sealer and devital/vital teeth treated with AH Plus sealer. Patients were prescribed ibuprofen, a 200-mg analgesic, if needed, and postoperative pain was recorded by visual analogue scale at 6, 12, 24, and 72 h after obturation. Pain score and frequency of tablet intake were recorded and statistically analyzed. RESULTS: Results showed that there was no significant difference between groups in the incidence of postoperative pain; however, iRoot SP sealer was associated with less analgesic intake compared to AH Plus sealer. CONCLUSION: The use of different sealers did not significantly affect pain levels. CLINICAL RELEVANCE: iRoot SP sealer was associated with less analgesic intake compared to AH Plus sealer.

The effect of antibiotic pastes on microhardness of dentin.

AIM: The aim of this study was to evaluate the effect of various endodontic regeneration agents on the microhardness of human root dentin after contact for various time intervals. MATERIALS AND METHODS: Thirty-five extracted human maxillary incisors were selected. The canals were enlarged and fixed in acrylic resin blocks. Two sections were obtained from the middle-third of each root (n = 70). The root discs were divided randomly into three groups of 20 and a control group of 10. Baseline microhardness testing was completed using a microhardness tester. The root discs were placed in Petri dishes and then assigned randomly to triple antibiotic paste (TAP), double antibiotic paste (DAP), calcium hydroxide paste (CH) and the control group. The CH and two antibiotic pastes were placed in the Petri dishes, and the discs were covered completely with the mixtures. Microhardness tests were repeated in the same manner after weeks 1, 2 and 3. Data were analysed statistically with a chi-square and Fisher's exact test at the 5% significance level and post hoc analysis was performed. RESULTS: No significant change in dentin microhardness occurred in the control group (P > 0.05). Overall, the dentin microhardness values decreased after treatment with the CH and antibiotic pastes over all time intervals. The DAP group showed reduced Knoop hardness number (KHN) values compared with the TAP group at the 1 measurements (P < 0.01). Statistically significant differences were found among the control, DAP and TAP groups, but no difference was seen between the control and CH groups at the week 1 measurement. No significant difference was found between the DAP and TAP groups at the week 4 measurement. CONCLUSIONS: Applying DAP and TAP for 4 weeks significantly reduced the microhardness values of dentin discs compared with the baseline values.

Outcomes of periradicular surgery of maxillary first molars using a vestibular approach: a prospective, clinical study with one year of follow-up.

PURPOSE: The aim of the present prospective, randomized, controlled, clinical study was to compare the outcomes of periradicular surgery of the maxillary first molar tooth using the vestibular approach between 2 preoperative radiologic evaluation methods: cone beam computed tomography (CBCT) and conventional radiography. PATIENTS AND METHODS: Periradicular surgery was applied to the maxillary first molar tooth in 40 patients. The patients were divided into 2 groups. The patients in group 1 underwent examination and preoperative planning with CBCT, and the patients in group 2 underwent examination and preoperative planning with conventional radiography. The outcomes of the treatment were evaluated radiographically and clinically, and the data were analyzed statistically. RESULTS: The mean operative time was significantly shorter in group 1 than in group 2. According to the radiographic and clinical healing criteria used in the present study, the healing of patients in group 1 was rated as a success in 35%, an improvement in 40%, and a failure in 25%. In the group 2 patients, healing was rated as a success in 42.1%, an improvement in 31.6%, and a failure in 26.3%. Sinus membrane elevation was performed in 92.3% of all patients. Sinus membrane perforation occurred in 20% of the patients in group 1 and 36.8% of the patients in group 2. CONCLUSIONS: Periradicular surgery of maxillary first molars using a vestibular approach is a viable treatment method with a low complication rate. Preoperative CBCT examination demonstrated positive contributions to the treatment outcomes.

Effects of ultrasonics and trephine burs on dentinal microcrack formation during broken instrument removal procedures: A micro-CT analysis.

The objective of this study was to compare the effects of ultrasonic and trephine burs on microcrack formation during the removal of broken instruments, utilising micro-computed tomography (Micro-CT). Twenty-five extracted human mandibular molars were used for this study. The hand files were fractured into the mesiobuccal canal, except in the control group. In the ultrasonic group (n = 10), ultrasonic tips were used to retrieve the instrument, while in the trephine group (n = 10), trephine burs (Meitrac, Meisinger) and an extractor device were utilised. For the control group (n = 5), only staging platform was prepared. After the removal procedures, micro-CT images were obtained from the specimens. The chi-squared test was used to analyse the data, and significance was considered to be p < 0.05. Overall, 15 736 cross sections were analysed. No significant differences were found between control and experimental groups. Removal of broken instruments with trephine burs caused significantly more dentinal microcracks compared with ultrasonics (p = 0.016).

Effect of QMix as final irrigation protocol on periapical healing after single-visit root canal treatment: A randomised controlled clinical trial.

The aim of this study was to evaluate radiographic periapical repair after endodontic treatment using QMix or NaOCl irrigation in single-rooted teeth with apical periodontitis. In this randomised clinical trial, 60 patients were selected and randomised into two groups (n = 30). After instrumentation of root canals, QMix or NaOCl was used as a final irrigation and the canals obturated with gutta-percha and AH Plus sealer. All the participants were recalled after 12 months and 15 patients were lost to the study so 45 patients were evaluated radiographically according to periapical index (PAI) scores. A significant decrease was seen in PAI scores after 1 year in all patients (p < 0.001). In the QMix and NaOCl group, absence or reduction of radiolucency was observed in 23 of 25 teeth (92%) and 20 of 20 teeth (100%), respectively. There was no significant difference between two groups according to the decrease in PAI score (p = 0.508). Root canal treatments with or without QMix irrigation contributed equally to periapical healing.

Silorane-based composite: depth of cure, surface hardness, degree of conversion, and cervical microleakage in Class II cavities.

OBJECTIVE: The purpose of this study was to determine the depth of cure, degree of conversion (DC), hardness, and cervical sealing ability of silorane-based composite (Filtek Silorane [FS; 3M, Seefeld, Germany]) and to compare with methacrylate-based composites (MBCs = Filtek Supreme XT [FSXT] and Filtek P60 [FP60]). MATERIALS AND METHODS: The DC and hardness of every material were evaluated after 1, 7, and 30 days. The depth of cure was determined using the ISO 4049:2000 standard. Microleakage was evaluated by measuring dye penetration across the gingival wall in cross-sectioned specimens. RESULTS: FS showed lower depth of cure than FSXT and FP60. The DC of FS was significantly lower when compared to FP60 and FSXT. FS exhibited lower hardness than both FSXT and FP60 after 1 day of storage. The hardness of FS remained unchanged during the storage period. FS showed reduced microleakage scores compared to FSXT and showed similar microleakage scores compared to FP60. CONCLUSIONS: In conclusion, the DC and cure depth of FS are lower than those of MBCs. However, FS revealed stable hardness in water that is comparable to MBCs. The sealing ability of FS is similar or even better than that of MBCs.

Effect of different light sources in combination with a light-transmitting post on the degree of conversion of resin composite at different depths of simulated root canals.

AIM: The aim of this study was to evaluate the degree of conversion (DC) of composite resin at different depths of simulated immature root canals using light-transmitting plastic post (LTPP) and three different light sources. METHODOLOGY: Composite resin was packed into 60 black plastic cylinders 12mm in length with 4mm internal diameters to simulate immature root canals. LTPPs were inserted into half of the simulated canals and the other half acted as controls. Both the simulated canals with LTPPs and the controls were divided into three groups of 10, and each group was cured using either a quartz-tungsten-halogen (QTH), light-emitting diode (LED), or plasma arc (PAC) curing unit. Specimens were sectioned in three horizontally 24h after curing to represent cervical, middle, and apical levels. DC for each section of composite resin was measured using a Fourier transform infrared spectrophotometer, and data were analyzed using three-way anova and Tukey tests. RESULTS: At the cervical level, no significant differences were found between specimens cured using different light sources or between specimens with and without LTPPs (P>0.05). However, DC was significantly higher in specimens with LTPPs than in those without LTPPs at both the middle and apical levels (P<0.05). The mean DC of all specimens with LTPPs was significantly higher than that of specimens without LTPPs (P<0.05). PAC unit showed lower DC than QTH and LED units at both the middle and apical levels; however, the differences were not statistically significant (P > 0.05). CONCLUSIONS: The results of this study suggest that the use of a LTPP increased the DC of composite resin at the middle and apical levels of simulated immature root canals, but that DC was independent of type of light source.

Effects of food-simulating liquids on the mechanical properties of a silorane-based dental composite.

The purpose of this study was to investigate the effects of food-simulating liquids (FSL) on the hardness and flexural strength (FS) of a new silorane-based composite and to compare it with methacrylate-based composites (MBCs). Four restorative materials (Filtek Silorane, P60, Z250, and Supreme XT) were used. Specimens for the FS and hardness measurements were fabricated in customized molds. Immediately after polymerization, the materials were stored in the following dietary simulating solvents at 37 degrees C for 1 week: distilled water, 0.02 N citric acid, heptane, and 75% aqueous ethanol solution. After conditioning, the FS and hardness values were measured. Data were subjected to ANOVA/Scheffé's test at a significance level of 0.05. The hardness and FS of Filtek Silorane were not significantly affected by FSL (p>0.05). Conversely, the hardness of MBCs significantly decreased after conditioning in water and ethanol (p<0.05). Similarly, the FS values of MBCs were significantly affected after conditioning in ethanol.

Effects of sodium hypochlorite and chlorhexidine solutions on Resilon (synthetic polymer based root canal filling material) cones: an atomic force microscopy study.

The aim of the present study is to evaluate the effects of 2% chlorhexidine and 5.25% sodium hypochlorite on the surface properties of Resilon cones with the atomic force microscopy. The Resilon cones were immersed in disinfecting agents (5.25% sodium hypochlorite and 2% chlorhexidine) at 1 and 5 min time intervals. Atomic force microscopy was used to evaluate topographical deviations of Resilon cones. Root mean square (RMS) parameters for topographic amplitudes were calculated. The cones exhibited statistically significant low RMS values at 5-min immersion in sodium hypochlorite and chlorhexidine groups compared to the all other groups (p < 0.05). One-minute immersion did not show any significant deterioration on the Resilon surface (p > 0.05). In conclusion, sodium hypochlorite and chlorhexidine solutions used for disinfection significantly decreased (p < 0.05) the RMS values of Resilon cones at 5-min applications.

The oral health status of street children in Adana, Turkey.

AIM: To determine the oral health status of street children and compare the results with a group of non-working children in Adana, Turkey. Street children are generally defined as any boy or girl for whom the street has become his or her habitual abode and/or source of livelihood; and who is inadequately protected, supervised, or directed by responsible adults. STUDY DESIGN: Demographic data including education, employment and social insurance of parents and number of siblings, was obtained. A formal interview with structured questions was used in order to determine the oral health behaviour of the children. Oral examinations were performed according to the criteria of the WHO oral examination form. RESULTS: The oral health behaviour of street children was significantly different from non-working children. While DMFT and dmft scores of the street youths were significantly lower than the control group, they had higher CPITN scores (p< or =0.001). CONCLUSION: Street children are commonly faced with oral health problems, especially periodontal problems. Therefore, the dental and periodontal needs of this particular population must be addressed. Oral health policies and preventive services including oral health promotion programmes which aim to give information about dental issues and to make positive changes in behavioural and environmental factors should be developed. The priority should be to control the factors which result in the occurrence of new dental problems.

Effect of irrigation technique for removal of triple antibiotic paste on bond strength of MTA to root dentin.

This study evaluated the bond strength of mineral trioxide aggregate (MTA) to root canal dentin after the performance of various irrigation procedures to remove triple antibiotic paste (TAP). A total of 56 single-rooted human mandibular premolars were instrumented using a rotary system to size 40 and divided randomly into a control group (no intracanal dressing) and three experimental groups (TAP application for 28 days). TAP was then removed by rinsing with 10 mL 2.5% NaOCl using three irrigation systems (Vibringe sonic irrigation, CanalBrush, and syringe irrigation). The coronal and middle parts of root canals were then obturated with MTA. After storage for 1 week, each specimen was embedded in an acrylic block and sectioned horizontally (2-mm-thick slices) at two levels (coronal and middle). Bond strength of MTA to root canal dentin was assessed in 28 samples per group via push-out test using a universal testing machine. Data from the four groups were compared using one-way analysis of variance. Tukey's test was used for multiple comparisons. Push-out bond strength values were significantly higher in the control and Vibringe groups than in the CanalBrush and syringe irrigation groups (p < 0.001). TAP removal from root canals with the Vibringe irrigation system may increase the push-out bond strength of MTA compared with the use of the CanalBrush or syringe irrigation.

Antibacterial Efficacy of Calcium Hypochlorite with Vibringe Sonic Irrigation System on Enterococcus faecalis: An In Vitro Study.

Aim. The purpose of this study was to compare the in vitro efficacy of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with sonic (Vibringe) irrigation system in root canals which were contaminated with Enterococcus faecalis. Material and Methods. The root canals of 84 single-rooted premolars were enlarged up to a file 40, autoclaved, inoculated with Enterococcus faecalis, and incubated for 21 days. The samples were divided into 7 groups according to the irrigation protocol: G0: no treatment; G1: distilled water; G2: 2.5% NaOCl; G3: 2.5% Ca(OCl)2; G4: distilled water with sonic activation; G5: 2.5% NaOCl with sonic activation; and G6: 2.5% Ca(OCl)2 with sonic activation. Before and after decontamination procedures microbiological samples were collected and the colony-forming units were counted and the percentages of reduction were calculated. Results. Distilled water with syringe irrigation and sonic activation groups demonstrated poor antibacterial effect on Enterococcus faecalis compared to other experimental groups (p < 0.05). There was no statistically significant difference between syringe and sonic irrigation systems with Ca(OCl)2 and NaOCl. Conclusion. The antimicrobial property of Ca(OCl)2 has been investigated and compared with that of NaOCl. Both conventional syringe irrigation and sonic irrigation were found effective at removing E. faecalis from the root canal of extracted human teeth.

Microhardness of composites in simulated root canals cured with light transmitting posts and glass-fiber reinforced composite posts.

The aim of this study was to evaluate the depth of cure of composite resin cured within simulated root canals by means of light-transmitting plastic posts, glass-fiber-reinforced composite posts, and conventional light curing method. Thirty black plastic cylinders measuring 15 mm in length and 4 mm in internal diameter were divided into three groups. The composite resin was packed into simulated canals. The light-transmitting plastic posts and glass-fiber-reinforced composite posts were inserted into simulated canals and light cured for 90 seconds. The control group was light cured directly. To ensure continual change of material properties by increasing the length of material, a surface microhardness test was done 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, and 14 mm from the light exposure surface. The results showed a significant increase in microhardness of composite resin (depth of cure) for both light-transmitting plastic posts and glass-fiber-reinforced composite posts compared with the control group. The microhardness of composite resin was also significantly higher with light-transmitting plastic posts than glass-fiber-reinforced composite posts after 8 mm.

Apical microleakage of root-end cavities prepared by CO2 laser.

This in vitro study in extracted human teeth was designed to compare the degree of dye penetration of root-end cavities prepared by CO2 laser, ultrasonic retrotip, or rotary instrument. Eighty-two human anterior teeth were prepared and obturated with laterally condensed gutta-percha and sealer. Root-end resection was performed at 90 degrees, 3 mm from apex. Root-end cavities were prepared by CO2 laser beam, ultrasonic retrotips, or bur and were filled with amalgam. The teeth were isolated and immersed in basic fuchsin at 36 degrees C for 48 hours. The roots were split longitudinally and examined by a stereomicroscope. Leakage was quantified by linear measurement of dye penetration with the aid of image-analyzing software. Apical leakage in the CO2 laser group was significantly less than in the ultrasonic retrotip and bur groups. The difference between the ultrasonic and bur groups was insignificant. Based on the results of this in vitro study, application of CO2 laser for root-end cavity preparation appears to decrease the apical leakage.

Microhardness of packable composites used as posts condensed with different methods.

The purpose of this in vitro study was to evaluate the microhardness of packable composite compacted with hand or ultrasonic pluggers in post spaces. A total of 168 extracted human anterior teeth were prepared with Gates Glidden and ParaPost drills after obturation. A primer and a dentin-bonding agent were applied to the etched surface. Half of the specimens were compacted with an ultrasonic tip and the other half with a mechanical hand compactor and all specimens were polymerized for each increment. The roots were then sectioned horizontally from 0, 2.5, 3, 3.5, 4, 4.5, and 5 mm starting from the coronal and sliced 2.5-mm long. The microhardness test was applied to each specimen. There were statistically significant differences between ultrasonically and hand-condensed groups in whole specimens (p < 0.001). There were no significant differences between groups of 0, 2.5, and 3 mm until 3.5 mm was reached. After 3.5-mm depth, there were significant differences between the groups (p < 0.001). Ultrasonic condensation of packable composites provided mechanical advantage over hand condensation in root canals measuring microhardness in different depths. However, when microhardness was measured at different depths, values decreased after the depth of 3.5 mm in both condensation groups.

Perforation risks associated with the use of Masserann endodontic kit drills in mandibular molars.

PURPOSE: The use of Masserann kit is a frequently recommended technique for the removal of canal obstructions. Although this technique is usually successful, it may cause excessive removal of dentin tissue in root canals. The aim of this study is to evaluate the perforation risk and the remaining dentin thickness in mesial canals of mandibular molars following the use of Masserann kit. STUDY DESIGN: Fifty-three extracted human mandibular molars were selected for the study. The teeth were separated into 3 groups based on the degree of curvature of the root canals. By using Radio Visio Graphy and Coral Draw 8.0 software packages, the dentin/cement thickness of root canal was measured before and after the use of Masseran kit drills. RESULTS: In the severely and moderately curved mesial root of mandibular molars, the Masserann Kit increased the risk of creating thin or perforated walls. Additionally, after 7.5mm depth of drilling, the percentage of perforations increased in all groups. CONCLUSIONS: With respect to endangering the dentinal walls towards the apex of root canals, Masserann kit drills were found to increase the risk of perforations in curved canals and in deep preparations.

Postoperative pain after endodontic retreatment: single- versus two-visit treatment.

OBJECTIVE: The purpose of this clinical study was to determine the effect of 1- or 2-visit root canal treatment on the postoperative pain in the retreatment cases. STUDY DESIGN: Two hundred eighteen cases that required retreatment were included in the study. Obturated and unfilled canal space and the status of periapical tissues were evaluated according to the PAI index. The patients were subcategorized in regard to the presence or the absence of preoperative pain. Approximately half of each category was treated in 1 appointment. After removing the previous root canal obturation materials and biomechanic preparation of root canals, the teeth in the 1-visit group were obturated at the first appointment by using AH 26 sealer and laterally compacted gutta-percha, and those in the 2-visit group were medicated with calcium hydroxide-chlorhexidine combination and then closed with a temporary filling material. One week after the initial appointment, patients were asked about the occurrence of postoperative pain. The level of discomfort was rated as no pain, mild pain, moderate pain, or severe pain (flare-up). Data were statistically analyzed using the chi-squared and Fischer exact tests. RESULTS: Eight patients from the 1-visit group and 2 patients from the 2-visit group had flare-ups. There was a statistical difference between the groups (P <.05). Two-visit root canal treatment was more effective in completely eliminating pain than 1-visit treatment of previously symptomatic teeth (P <.05). CONCLUSIONS: Two-visit endodontic treatment with intracanal medication was found to be effective in reducing postoperative pain of previously symptomatic teeth and decreased the number of flare-ups in all retreatment cases.

Dentinal microcrack formation during root canal preparations by different NiTi rotary instruments and the self-adjusting file.

INTRODUCTION: The purpose of this study was to compare dentinal microcrack formation while using hand files (HFs), 4 brands of nickel-titanium (NiTi) rotary files and the self-adjusting file. METHODS: One hundred forty mandibular first molars were selected: 20 teeth were left unprepared and served as control, and the remaining 120 teeth were divided into 6 groups. HFs, HERO Shaper (HS; Micro-Mega, Besancon, France), Revo-S (RS, Micro-Mega), Twisted File (TF; SybronEndo, Orange, CA), ProTaper (PT, Dentsply Maillefer), and SAFs were used to prepare the 2 mesial canals. Roots were then sectioned 3, 6, and 9 mm from the apex, and the cut surface was observed under a microscope and checked for the presence of dentinal microcracks. RESULTS: The control, HF, and SAF groups did not show any microcracks. In roots prepared with the HS, RS, TF, and PT, dentinal microcracks were observed in 60%, 25%, 44%, and 30% of teeth, respectively. There was a significant difference between the control/HF/SAF group and the 4 NiTi rotary instrument groups (P < .0001). However, no significant difference was found among the 4 NiTi rotary instruments (P > .005). CONCLUSIONS: All rotary files created microcracks in the root dentin, whereas the SAF file and hand instrumentation presented with satisfactory results with no dentinal microcracks.