Introduction: The purpose of this study was to evaluate the prevalence of dental anomalies in a subpopulation of orthodontic patients with agenesis of maxillary lateral incisors (MLI). Methods:The material of the present study included the records of the 1964 orthodontic patients. Panoramic radiographs and dental casts were used to analyze other associated eight dental anomalies, including agenesis of other teeth, dens invaginatus, dens evaginatus, peg shaped MLI, taurodontism, pulp stone, root dilaceration and maxillary canine impaction. Results: Out of the 1964 patients examined, 90 were found to have agenesis of MLI, representing a prevalence of 4.6%. The most commonly found associated-anomalies were agenesis of other teeth (23.3%), peg-shaped MLIs (15.6%), taurodontism (42.2%), and dilacerated teeth (18.9%). Conclusion:Permanent tooth agenesis, taurodontism, peg-shaped maxillary lateral incisor, and root dilacerations are frequently associated with maxillary lateral incisor agenesis.

All systems caused apical debris extrusion during curved canal preparations. However, the PTG, PTN, and RECIPROC systems resulted in significantly less debris extrusion than the PTU system.

Background: A combination of antibiotics, including metronidazole (MET), ciprofloxacin (CIP), and minocycline (MINO), has been demonstrated to disinfect bacteria in necrotic teeth before regenerative processes. It has been presented clinically that antibiotic pastes may drive to possible stem cell death, difficulties in removing from the canal system, which can limit the regenerative procedure. This study was designed to (1) synthesize nanofibrous webs containing various concentrations of different medicaments (triple, double, and calcium hydroxide, Ca(OH)2), (2) coat this electrospun fibrous gutta-percha (GP) cones. Methods: Poly(vinylpyrrolidone) (PVP)-based electrospun fibrous webs were processed with low medicaments’ concentrations. Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDX), and X-Ray Photoelectron Spectroscopy (XPS) were carried out to investigate fiber morphology, antibiotic incorporation, and characterized GP-coated fibrous webs, respectively. The chemical and physical properties of dentine were carried out via Fourier Transform Infrared Spectroscopy (FTIR) and Nano-SEM, respectively. The antimicrobial properties of the different fibrous webs were assessed against various bacteria by direct nanofiber/bacteria contact. Cytocompatibility was measured by applying the MTT method. Results: The mean fiber diameter of the experiment groups of medicament-containing fibers ranged in the nm scale and was significantly smaller than PVP fibers. EDX analysis confirmed the presence of medicaments in the nanofibers. XPS analysis presented a complete coating of the fibers with GPs; FTIR and Nano-SEM showed no chemical and physical configuration of intracanal medicaments on the dentine surface. Meanwhile, nanofibrous webs led to a significant reduction in the percentage of viable bacteria compared with the negative control and PVP. Conclusion: Our findings suggest that TA-NFs, DA-NFs, and Ca(OH)2)-NFs coated GP cones have significant potential in eliminating intracanal bacteria, cell-friendly behavior, and clinical usage features.

BackgroundThe aim of this study was to evaluate the bond strength of AH plus, Acroseal, and Adseal to the root canal dentin.MethodsA total of 36 single-rooted, mandibular premolar teeth were used. Root canal shaping procedures were performed with ProTaper rotary instruments (Dentsply Maillefer) up to size F4. The prepared samples were then randomly assembled into 3 groups (n = 12). For each group, an ultrasonic tip (size 15, 0.02 taper) which was also coated with an epoxy resin based sealer and placed 2 mm shorter than the working length. The sealer was then activated for 10 s. A push-out test was used to measure the bond strength between the root canal dentine and the sealer. Kruskal-Wallis test to evaluate the push-out bond strength of epoxy based sealer (P = 0.05). The failure mode data were statistically analyzed using Pearson’s chi square test (P = 0.05).ResultsKruskal-Wallis test indicated that there were no statistically significant difference among the push out bond strength values of 3 mm (p = 0.123) and 6 mm (P = 0.057) for groups, there was statistically significant difference push out bond strength value of 9 mm (P = 0.032). Pearson’s chi square test showed statistically significant differences for the failure types among the groups.ConclusionVarious epoxy resin based sealers activated ultrasonically showed similar bond strength in oval shaped root canals. Apical sections for all groups have higher push out bond strength values than middle and coronal sections.Electronic supplementary materialThe online version of this article (doi:10.1186/s12903-016-0301-1) contains supplementary material, which is available to authorized users.

Purpose: The purpose of the present study is to assess the rate of newly formed microcracks comparatively during root canal instrumentation by using ProTaper Next, Reciproc, and Self-Adjusting File systems using micro-computed tomography. Subjects and methods: Thirty mesial roots of mandibular molars were randomly assigned to 3 experimental groups (n = 10) as follows, ProTaper Next, Reciproc and Self-Adjusting File system. Preoperative and postoperative scans were obtained at the isotropic resolution of 13.68 µm. Cross-section images were examined to identify the presence of newly formed dentinal microcracks. Results: The Self-Adjusting File and Reciproc systems caused a higher rate of new microcrack formation than the ProTaper Next group (p<0.001). There were also significant differences in the new microcrack formation between Reciproc and Self-Adjusting File groups (p<0.001). Conclusion: Reciproc and Self-Adjusting File systems caused a higher rate of newly formed microcraks compared to ProTaper Next system.

The results of this study showed that SAF system after Mtwo retreatment system and ProTaper retreatment system for improving retreatment has no significant effect on the amount of debris extruded apically.

Objective: The aim of this retrospective study was to investigate the effect of photobiomodulation therapy on postoperative pain provoked by thermal stimulation in direct pulp capping. Subject and methods: A retrospective study was performed using the records of patients who received direct pulp capping using mineral trioxide aggregate. Teeth irradiated with a laser were assigned as the photobiomodulation therapy group and non-irradiated teeth were considered as the control group. Before treatment and 6 hours, 1 day and 7 days after treatment, tooth sensitivity to a cold stimulus was recorded using a visual analog scale. Results: From a total of 123 documented direct pulp capping procedures, only 72 directly capped permanent teeth met the inclusion criteria. Age, gender, and tooth location were comparable between the groups. A statistically significant difference was found in sensitivity to cold stimulus between groups on day 7 (p=.007), but no difference was found at the preoperative, 6 hour, and day 1 time points (p=.055, p=.132, p=.100, respectively). In the intragroup evaluation, a significantly greater decrease was detected in the photobiomodulation therapy group compared to the control group, although both groups showed a reduction in discomfort throughout the follow-up period (p=.000). Conclusion: Photobiomodulation therapy is an effective method for enhancing patient comfort by reducing thermal sensitivity following direct pulp capping procedures.

The purpose of this study was to evaluate mineral content of root canal dentin after treatment with different antibiotic pastes including the mixture of metronidazole, ciprofloxacin, doxycycline, cefaclor, amoxicillin, or minocycline. Fifty extracted maxillary canine teeth were randomly divided into five groups (n = 10 teeth for each group). Root canals were prepared Reciproc rotary files. Canals were irrigated using 5 ml 5% NaOCl and 1 ml 15% EDTA. Each tooth in all groups were longitudinally splitted into two pieces as a control and experimental samples. Each experimental group received following antibiotic paste; double antibiotic paste (DAP) and triple antibiotic paste with doxycycline (TAPd), TAP with cefaclor (TAPc), TAP with amoxicillin (TAPa), and TAP with minocycline (TAPm) for 21 days. The Ca, P, Mg, Ca, and K levels, and the Ca/P ratio was analyzed by a scanning electron microscope (SEM) equipped using a Bruker energydispersive X-Ray (EDX) detector. Data were analyzed with independent samples t-test, one-way ANOVA, and Duncan tests. Ca and Ca/P ratio showed a statistically significant increase TAP with amoxicillin and cefaclor (p < .05). DAP, TAPd, and TAPm did not change the mineral levels (p > .05). TAPa and TAPc with increased the Ca level and Ca/P ratio of the root canal dentin which consequently positively influences the revascularization process.