Evaluation of the efficacy of rotary and reciprocating systems for the removal of filling material for various root canal filling techniques.

Background: This study aimed to evaluate the efficacy of various filling and retreatment techniques for oval-shaped root canals. Methods: Sixty distal roots of mandibular molar teeth were included in the study. The roots were prepared using the ProTaper Next (PTN) X4 rotary system and irrigation with 2.5% NaOCl. The roots were then divided into three groups and filled with Total Fill BC Sealer (FKG Dentaire) using three different techniques (n=20): single cone (SC), GuttaCore (GC), and warm vertical condensation (WVC). The retreatment procedure was performed using two different instrumentation techniques: Reciproc 50 (R50) and PTN X5 (n=10). To analyze the remaining filling material, the roots were divided buccolingually in two parts with the help of diamond separators, and photographs were taken at x16 magnification using a dental operating microscope (DOM). The ratio of the remaining filling materials was calculated using image analysis software and statistically evaluated using the Kruskal-Wallis test. Results: None of the assessed retreatment procedures completely removed the filling materials from the root canals. For both instrumentation techniques, more root canal filling material remained in the WVC group (P<0.05). Conclusion: The GC filling technique had a higher cleaning percentage than the WVC and SC techniques in the coronal region. The R50 system was found to be superior to the PTN X5 system for retreatment, and the root canal fillings applied using the WVC technique were more difficult to remove than the fillings applied using the other techniques.

Finite Element Analysis of Stress Distribution in Root Canals When Using a Variety of Post Systems Instrumented with Different Rotary Systems.

It is very important for clinicians to provide restorative treatments that provide durability for endodontically treated teeth. Trauma, occlusal premature contact, and features of teeth are some of the issues that can cause vertical root fractures (VRFs) in root canal-treated teeth. The aim of this 3-D study was to compare stress distribution on mandibular premolar teeth when using a variety of post designs instrumented with different rotary systems. Six mandibular premolar teeth were instrumented with the following tools: ProTaper Next, WaveOne (WO), Reciproc (R), ReciprocBlue (RB), F6-Skytaper, and TF-Adaptive. Teeth were scanned using cone beam computed tomography (CBCT) and the images were transferred to the Catia V5R25 software. Data were recorded in a stereolithography (STL) format. Four different post systems were used, fabricated from metal, fiber, zirconia, and titanium, respectively. Dentin, gutta, post, core, and crown models were added to the solid model. ANSYS V17.2 finite element analysis (FEA) software was used to determine stress distribution on each assembly. Finite analysis models were created that allowed for the calculation of stress distribution of 250-N loading at a 45° angle and vertical in relation to the roots. The maximum principal stress and von Mises values were higher under oblique loading on the roots. The F6-Skytaper and WO systems showed lower stress than other systems. The TF-Adaptive instrument showed higher stress distribution than the other models. Fiber and titanium posts showed lower stress than others. The F6-Skytaper, R, and RB instruments were found to be most effective in terms of displacement of the crown, resulting in the lowest stress values. Fiber and titanium posts showed better results than other post systems, while root canals instrumented with the F6-Skytaper and WO instruments were less likely to result in root fractures.

Effect of EDDY and manual dynamic activation techniques on postoperative pain in non-surgical retreatment: a randomized controlled trial.

BACKGROUND: During non-surgical retreatment process, the products such as dentin debris, root canal fillings, irrigation solutions, microorganisms and remaining pulp tissues can extrude to the apical area and can cause the postoperative pain and flare-up. Thus, the aim of this study was to evaluatethe effect of EDDY and manual dynamic activation (MDA) techniques on postoperative pain (PP) associated with retreatment. METHODS: Ninety patients scheduled for retreatment were treated at a single visit. Non-vital mandibular premolar teeth diagnosed with asymptomatic apical periodontitis were included in this study. The patients were divided into two groups (n = 45) on the basis of the need for additional irrigation activation procedures (EDDY and MDA). The patients' post-treatment pain levels were asked to rate the intensity of their pain on a 10-point numerical rating scale (NRS) at the 12th, 24th, 48th, and 72nd h and 7 days.The data were analyzed using the chi-square and Wilcoxon signed-rank test was used for within-group comparisons and Mann Whitney U test was used to compare the groups by time period. RESULTS: The difference in postoperative pain intensity between two groups was statistically significant at 12, 24, 48, and 72 h (p < 0.05). There was no significant difference at 7 days. Moreover, no statistically significant difference was found between the two groups in terms of gender and analgesic medication intake (p > 0.05). Pain intensity after the treatment was lesser in the MDA groupthanin the EDDY group at 12, 24, 48, and 72 h. CONCLUSION: This study could lead us to conclude that the two activation systems can be used during endodontic retreatment with no difference at PP 7 days later. However, a comparison of the groups indicated that the EDDY resulted in significantly more PP at 12, 24, 48, and 72 h. Trial registration ClinicalTrials.gov Identifier: NCT04726670.

Effect of Qmix 2in1, chlorhexidine gluconate, and ethylenediaminetetraacetic acid on postoperative pain after root canal treatment: A double-blind randomized clinical trial.

Background. This study aimed to investigate the effects of different final irrigation solutions on postoperative pain following root canal treatment. Methods. Eighty-nine nonvital premolar and molar teeth with periapical lesions (PAI: 3‒4) without any clinical symptoms were included. The patients were randomly assigned to three groups according to the final irrigation solutions used: G1: 2 mL of Qmix (n=29), G2: 2 mL of 17% ethylenediaminetetraacetic acid (EDTA) (n=30), and G3: 2 mL of 2% chlorhexidine gluconate (CHX) (n=30). All the patients were prescribed 100 mg of flurbiprofen to use as needed for pain. The patients were asked to rate their pain status according to the verbal rating scale at 12, 24, 48, and 72 hours, and one week. The data were analyzed using Pearson's chi-squared test, Fisher's exact test, and chi-squared analysis with Monte Carlo simulation. The significance level was set at P≤0.05. Results. No significant differences were observed in postoperative pain rates at 12, 48, and 72 hours and one week (P>0.05). However, in the Qmix group, a significantly lower pain level was observed at 24 hours with EDTA and CHX (P=0.019). The rate of mild pain in the EDTA group at 72 hours (18.8%) was significantly higher in premolar teeth than in molar teeth (P=0.012). The moderate pain level in the EDTA group at 12 hours was significantly higher in those>60 years of age (P=0.008). Conclusion. The use of Qmix as an irrigation solution resulted in lower postoperative pain levels at 24 hours compared to other solutions. Therefore, Qmix can be considered a proper final irrigation solution in endodontic treatment regarding postoperative pain.

Evaluation of dentinal tubule penetration of Irritrol and chlorhexidine irrigating solutions activated using EDDY and photon-initiated photoacoustic streaming.

The aim of the study was to compare the penetration depth and percentage of Irritrol and chlorhexidine (CHX) solutions into dentinal tubules using conventional needle irrigation (CI), EDDY, and photon-induced photoacoustic streaming (PIPS). Sixty oval shaped mandibular premolar teeth were divided into two main groups according to the irrigating solutions as follows; Irritrol and CHX, which were later randomly divided into three subgroups according to the activation technique; CI, EDDY and PIPS (n = 10). Following the irrigation activation procedures, all roots were horizontally sectioned at 3 (apical), 8 (middle), and 13 (coronal) mm from the root apex and then examined with confocal laser scanning microscope (CLSM). Penetration depth (µm) and penetration percentage (%) as determined from the images were analyzed using LSM Image Browser software (Zeiss) and Image J analysis software (V. 1.44p; National Institutes of Health, Bethesda, MD), respectively. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests were performed for multiple comparisons. In both Irritrol and CHX groups, the PIPS activation system demonstrated the highest values for irrigant penetration depth and penetration percentage compared with the other activation methods. Activation of the CHX and Irritrol the final irrigating solutions with PIPS activation technique improved the penetration depth and percentage solutions into the dentinal tubules.

Micro-computed tomography assessment of triple antibiotic paste removal using different irrigation methods.

Purpose: The study aimed to compare four irrigation methods for triple antibiotic paste (TAP) removal using micro-computed tomography (micro-CT) analysis. Materials and methods: Forty bovine central incisor teeth were selected, and the root canals were prepared up to #6 Peeso reamer drills. Equal portions of metronidazole, ciprofloxacin, and minocycline were used for the TAP preparation. The TAP was prepared by mixing the powder with distilled water (with a powder to liquid ratio of 1 mg/1 mL). The TAP was introduced to the canals with a lentulo spiral; then, the access cavities were temporarily sealed. After 21 days of storage, the teeth were randomly divided into four equal groups according to irrigation techniques: open-ended, side-vented, double side-vented needle irrigations and EndoActivator irrigation device. The TAP was removed using 17% EDTA (20 mL) and distilled water (5 mL) for all of the groups. The volume of the intracanal medicament before and after the irrigation procedure was recorded by scanning the samples with micro-CT, and the TAP percentage was calculated. The percentages obtained from each group were compared using ANOVA. The significance level was set at p<0.05. Results: The results showed that there was no statistically significant difference among the TAP percentage volumes removed by the different irrigation techniques. Conclusion: The irrigation techniques used in this study showed similar TAP removal efficiency, however, they could not completely remove the TAP from the root canal systems.

Evaluation of the effect of periapical lesions and other odontogenic conditions on maxillary sinus mucosal thickness characteristics and mucosal appearance: A CBCT study.

Background. This retrospective study aimed to investigate the effect of various dental and maxillary sinus variables on maxillary sinus mucosal thickness (MT). The variables included periodontal bone loss (PBL), periapical status, dental restorations of posterior maxillary teeth, and the distance from the root apices to the sinus mucosa. Methods. Cone-beam computed tomography (CBCT) images of the maxillary sinuses (n = 600) in 300 patients were examined. The sinus MT and the distance of the roots from maxillary sinuses were measured. Apical lesions of the roots, PBL, and situations of adjacent teeth were recorded. The relationships between these conditions and MT and characterization of MT were evaluated. The Kruskal-Wallis H test was used to compare groups due to the non-normal distribution of the data. The relationship between categorical variables was analyzed using chi-squared test. Results. There was a significant correlation between maxillary sinus MT and periapical lesions, PBL, and restorations (P < 0.05). MT increased as the apical lesions of premolar teeth enlarged (P < 0.05, P = 0.022). MT increased in cases of mild PBL of molar teeth (P = 0.041). Conclusion. In this retrospective study, the MT significantly increased in patients with periapical lesions, inadequate endodontic treatment, increased PBL, and inadequate dental restorations.

The retreatment abilities of ProTaper Next and F6 Skytaper: a micro-computed tomography study.

PURPOSE: The aim of this study was to evaluate the retreatment abilities of the ProTaper Next (PTN) and F6 SkyTaper (F6) systems by using micro-computed tomography (microct), radiographic and microscopic imaging techniques. MATERIALS AND METHODS: The root canals of twenty-six extracted mandibular premolar teeth were prepared and obturated. For the retreatment procedure, the teeth were randomly divided into two equal groups according to endodontic instruments: PTN (X4) and F6 (#40/.06). Pre- and post-operative filling material volumes were measured with micro-ct, and areas were measured with radiographic and microscopic imaging techniques. The percentages of residual material were calculated, and then statistically compared. The significance level was set at p<0.05. RESULTS: There was no statistically significant difference between F6 and PTN for retreatment efficacy in the micro-ct and radiographic imaging techniques (p>0.05). PTN demonstrated better cleaning ability when evaluated by microscopic imaging. (p<0.05). The correlation was moderate between micro-ct and radiographic, and micro-ct and microscopic imaging groups; however, it was strong between radiographic and microscopic imaging methods. CONCLUSION: The PTN and F6 files had similar effects in the removal of filling material with microct evaluation. The radiographic imaging method gave similar results with micro-ct imaging.

Evaluation of different Apexification treatments of teeth with immature apices and apical periodontitis on the fractal dimensions of trabecular bone.

The aim of the present study was to investigate in the fractal dimension (FD) time-dependent changes of periapical bone after two different apexification treatments in teeth with immature apices and apical periodontitis. This study included 55 cases treated with apexification. Cases were divided into two groups: a calcium hydroxide group and a mineral trioxide aggregate group. In each case, the lesion area was evaluated by fractal analysis on periapical radiographs obtained before and 1-year after treatment via Image-J program. The FD of each region of interest on the radiographs was calculated using the fractal analysis method. The data were statistically analysed. In both groups, the FD values increased compare to initial at 1-year follow-up after treatment (P < .05). There was no statistically significant difference between the groups in terms of the time-dependent increase in FD values (P = 0.118). In the present study, time-dependent changes in FD were independent of the apexification method.

Comparison of apical debris extrusion using EDDY, passive ultrasonic activation and photon-initiated photoacoustic streaming irrigation activation devices.

The study aimed to determine the effect of different irrigation activation systems on the amount of apical debris extrusion in mandibular molar teeth with curved root canals. Sixty extracted mandibular molar teeth were instrumented with HyFlex EDM system and divided into four groups according to irrigation techniques: passive ultrasonic irrigation (PUI), EDDY, photon-initiated photoacoustic streaming (PIPS) and manual irrigation (MI). After the final irrigation, the extruded irrigants were collected into Eppendorf tubes of known weights. The amount of extruded debris was obtained by subtracting the weight from the initial weight of the tube. The Kruskal-Wallis test was used for statistical analysis. EDDY caused significantly more debris extrusion than the other irrigation activation systems (P < 0.001). PUI caused less apical debris extrusion but there was no statistical difference between PUI, PIPS and MI (P > 0.05). The EDDY activation system was associated with the highest amount of debris extrusion in curved root canals.

Fracture resistance of roots enlarged with various rotary systems and obturated with different sealers.

Background. This in vitro study compared the fracture resistance of roots instrumented either with ProTaper or One Shape rotary systems and filled with one of the silicate, epoxy resin or silicone-based sealers. Methods. Sixty single-rooted extracted mandibular premolars were decoronated to a length of 13 mm and then randomly divided into two main groups (n=30) in terms of the rotary system used for preparation. Group 1 samples were instrumented with the ProTaper Universal system up to a master apical file of #F2, while samples in group 2 were enlarged with One Shape system. The two main groups were then divided into 3 subgroups in terms of the sealer used (n=10) and filled with guttapercha (either F2 or MM-GP points) of the rotary system used and one of the sealers as follows: group 1, BioRoot RCS + ProTaper F2 gutta-percha; group 2, AH Plus + ProTaper F2 gutta-percha; group 3, GuttaFlow + ProTaper F2 gutta-percha; group 4, BioRoot RCS+ MM-GP points; group 5, AH Plus + MM-GP points; and group 6, GuttaFlow + MM-GP points. Each specimen then underwent fracture testing by using a universal testing machine at a crosshead speed of 1.0 mm/min until the root fractured. Data were statistically analyzed. Results. Two-way ANOVA showed no significant differences between the groups. One Shape instruments showed significantly better fracture resistance compared to ProTaper instruments. Statistically, no significant difference was found between AHPlus, GuttaFlow and BioRoot RCS sealers. Conclusion. It can be concluded that the rotary system used for the instrumentation of teeth has some influence on the fracture resistance, while the root canal sealers do not have such an effect.

Salivary opiorphin in dental pain: A potential biomarker for dental disease.

OBJECTIVES: Opiorphin is a recently discovered peptide shown to inhibit the enkephalin-degrading enzymes and prolong the effects of enkephalins. Although opiorphin is found in high concentrations in saliva, the relationship between salivary opiorphin and orofacial pains is not yet fully understood. We aimed to determine salivary opiorphin concentrations in dental pain related to symptomatic irreversible pulpitis (SIP), and symptomatic apical periodontitis (SAP). DESIGN: 39 patients participated in this study. The participants were categorized into SIP and SAP based on their diagnosis. All the patients were treated with root canal treatment. Saliva specimens were collected, and pain levels were recorded at pre-treatment, 7 days post-treatment and 30 days post-treatment. Saliva opiorphin levels were measured using a commercially available ELISA kit. Pre-treatment and post-treatment opiorphin levels were evaluated using repeated measures ANOVA. Correlations between VAS scores, opiorphin levels and age were evaluated using Spearman's Rank Correlation. RESULTS: The average saliva opiorphin level pre-treatment, 7 days post-treatment and 30 days post-treatment were 31.28 ± 7.10 ng/ml, 20.41 ± 2.67 ng/ml and 18.61 ± 2.05 ng/ml respectively. Significantly higher pre-treatment opiorphin levels were observed in the SIP group compared to the SAP group. A strong correlation was observed between the pre-treatment pain levels and the saliva opiorphin concentrations. CONCLUSIONS: Our findings indicate that saliva opiorphin levels increase in inflammation related dental pain. The level of salivary opiorphin is strongly correlated with the reported level of pain. The extent of the inflammation (pulpal vs. periodontal) also affects the opiorphin level.