Histological Evaluation of the Effect of Platelet-rich Plasma on Pulp Regeneration in Nonvital Open Apex Teeth: An Animal Study.

AIM: Platelet-rich plasma (PRP), which is a concentration of growth factors found in platelets, may be a suitable material for pulp regeneration. The aim of this animal study was a histological evaluation of PRP on pulp regeneration in nonvital teeth with immature apices. MATERIALS AND METHODS: A total of 40 premolar dogs' teeth were chosen for this study. After general anesthesia, the teeth were exposed, and subsequently, pulps were removed and the cavities were opened to the oral cavity. After 2 weeks, root canals were irrigated and disinfected with sodium hypochlorite with noninstrumentation technique, and triple antibiotic paste was placed inside the canals. Cavities were sealed with a temporary restoration. About 4 weeks later, canals were irrigated again and the teeth were randomly divided into three groups. Bleeding was evoked with overinstrumentation, then experimental materials for each group [PRP, mineral trioxide aggregate (MTA), and parafilm respectively] were placed over the bleeding, and orifices were sealed with MTA and glass ionomer. After 3 months, dogs were sacrificed and the teeth were separated from the jaws and sections prepared for histological evaluation. RESULTS: Regeneration was shown in 44.7% of the samples. About 47.3% of the samples in the MTA group and 42.1% of the samples in the PRP group showed regeneration; however, no regeneration was observed in the parafilm group. Chi-square test showed no significant difference between groups I and II. The soft regenerative tissue included pulp-like tissue and vessels. Mineralized regenerative tissue included cementum-like, periodontal ligament-like, and bone-like tissues. No normal pulp and nerve tissue were observed. CONCLUSION: Both PRP and MTA may be ideal scaffolds to accelerate the regeneration process. CLINICAL SIGNIFICANCE: Pulp repair in immature permanent teeth with weak roots has a better outcome than replacement of the pulp with gutta-percha or biomaterials.

Five-year results of vital pulp therapy in permanent molars with irreversible pulpitis: a non-inferiority multicenter randomized clinical trial.

OBJECTIVES: Previous reported results of up to 12 months as well as 24-month follow-ups revealed superior and equivalent treatment outcomes for vital pulp therapy (VPT) using calcium-enriched mixture cement (CEM) in comparison with root canal therapy (RCT) for mature molars with established irreversible pulpitis, respectively. Present non-inferiority multicenter randomized clinical trial assesses the final long-term (5-year) results as well as the effects of patients' age/gender and the presence of preoperative periapical lesion on the treatment outcomes. MATERIALS AND METHODS: A total number of 407 patients were blindly allocated into two treatment groups [group 1 (VPT/CEM, n = 205) and group 2 (RCT, n = 202)] treated in 23 health-care centers by calibrated dentists. The treatment outcomes were assessed after 60 months. RESULTS: The 5-year results revealed no significant differences in the successes of both study arms (P = 0.29); a total number of 271 patients were available (~33 % were lost to follow-up). The patients' age/gender did not affect the outcomes; the presence of preoperative periapical lesion also did not implement a significant effect in both groups (P > 0.05). CONCLUSIONS: As an alternative for RCT, VPT/CEM can be considered as a valid treatment for vital mature permanent molars clinically diagnosed with irreversible pulpitis. CLINICAL RELEVANCE: Considering the favorable outcomes of 6- to 60-month follow-ups, as an evidence-based/simple/affordable/effective/biologic approach in cases of irreversible pulpitis, VPT/CEM is highly recommended for universal clinical practice.

Two-year results of vital pulp therapy in permanent molars with irreversible pulpitis: an ongoing multicenter randomized clinical trial.

OBJECTIVES: Oral healthcare expenses are increasing rapidly as a result of the growth of high-cost health technologies worldwide. In many developing/developed countries, low-cost tooth extraction is the alternative treatment option for a high-cost root canal therapy (RCT) for management of human molars with irreversible pulpitis. Vital pulp therapy with calcium-enriched mixture cement (VPT/CEM) as a new alternative treatment option has demonstrated excellent treatment outcomes up to 1 year; if 2-year radiographic/clinical effectiveness as well as cost-effectiveness of the VPT/CEM is also non-inferior compared with RCT, it can serve as a viable treatment for mature molars with irreversible pulpitis. MATERIALS AND METHODS: In this prospective, multicenter (n = 23), non-inferiority clinical trial, 407 patients were randomized to either one-visit RCT (n = 202) or VPT/CEM (n = 205) for 27 months. In this part of study, the primary outcome measure was the 2-year clinical and radiographic treatment outcomes. Cost-effectiveness was also analyzed. RESULTS: Mean follow-up times were 24.62 ± 0.72 and 24.61 ± 0.69 months in RCT (n = 166) and VPT/CEM (n = 166) arms, respectively. Clinical success rates in the two study arms were equal (98.19%); however, radiographic success rates were 79.5 and 86.7% in RCT and VPT/CEM arms, respectively, with no statistical difference (P = 0.053). The treatment time span mean was approximately three times greater in the RCT than in the VPT/CEM arm (94.07 vs. 31.09 min; P < 0.001). RCT had a cost of 171.5K per molar tooth compared with 44.5K for VPT. CONCLUSIONS: VPT/CEM reduced time and cost spent. When considering clinical as well as cost-effectiveness of VPT/CEM, this treatment option is not only non-inferior but also superior to RCT in mature permanent molar teeth with established irreversible pulpitis. CLINICAL RELEVANCE: Vital pulp therapy with CEM is a cost-effective and reliable biological technique for endodontic treatment of permanent molar teeth with irreversible pulpitis and can be recommended for general clinical practice.

Cell-Based Regenerative Endodontics for the Treatment of Irreversible Pulpitis: AnIn VivoInvestigation.

INTRODUCTION: This study aims to investigate the ability of umbilical cord mesenchymal stem cells (UC-MSC) to enhance the regeneration of pulp-dentin complex in immature permanent teeth with irreversible pulpitis. METHODS: A total of 32 mandibular premolar teeth with immature apices in 5 dogs were used in this in-vivo randomized controlled trial (RCT). Eight healthy teeth without pre-existing pathosis served as the positive control samples and received no treatment, while in another 8 teeth, the pulp was completely extirpated (negative control). Class V cavities were prepared to induce inflammation in the remaining 16 teeth (groups 3 and 4) and the pulp was extirpated 2-4 mm short of the radiographic apex. Of the 16, the 8 teeth in group 4 received 1 mL of cord blood stem cells with a hydrogel scaffold. Blood clots were covered with mineral trioxide aggregates at the cementoenamel junction in the experimental groups, and teeth were filled with RMGI and composite. Three months later, block sections were removed for histologic evaluations for the evaluation of postoperative apical closure, degree of inflammation, and presence of normal pulp tissue. The data were statistically analyzed with the chi-square test (P < .05). RESULTS: All teeth with complete pulp extirpation demonstrated pulpal necrosis with no postoperative closure of their apices, while apical closure was seen in all the teeth in the remaining groups. There was a statistically significant (P < .001) difference in the presence of inflammation and normal pulp tissue between the experimental groups. The teeth in group 3 showed normal pulp tissue extending to the level of MTA, but there was inflammation within the canal space. In contrast, the teeth in the UC-MSC group demonstrated organized, normal pulp tissue with no inflammation. CONCLUSION: Based on these results, the regeneration of the pulp-dentin complex is possible with no inflammation when UC-MSCs are used and 2-4 mm of the apical pulp remains intact in immature teeth with irreversible pulpitis.

One-year results of vital pulp therapy in permanent molars with irreversible pulpitis: an ongoing multicenter, randomized, non-inferiority clinical trial.

OBJECTIVES: Root canal therapy (RCT) and tooth extraction have been conventional treatment options for management of human mature teeth with irreversible pulpitis. Excellent short-term treatment outcomes of vital pulp therapy with calcium-enriched mixture cement (VPT/CEM), as a new treatment option, on postoperative pain relief was demonstrated; if intermediate- and long-term treatment outcomes of the new treatment are also non-inferior compared to RCT, then VPT/CEM may become a viable treatment option for management of mature teeth with irreversible pulpitis. MATERIALS AND METHODS: In 23 healthcare centers, 407 9- to 65-year-old patients were randomly allocated into two study arms including one-visit RCT (reference treatment; n = 202) and VPT/CEM (alternative treatment; n = 205). Six- and twelve-month clinical and radiographic successes were assessed. RESULTS: Mean follow-up times at 6- and 12-month follow-ups were "6.70 ± 0.68 and 6.72 ± 0.71 months" and "12.96 ± 0.67 and 12.90 ± 0.66 months" in the available cases of RCT and VPT/CEM arms, respectively. Favorable clinical success rates in the two study arms did not show statistical difference; however, the radiographic success rate in the VPT/CEM was significantly greater than RCT arm at the two follow-ups (P < 0.001). The patients' age had no effect on the treatment outcomes (P = 0.231). CONCLUSIONS: Treatment outcomes of VPT/CEM may be superior to RCT in mature molars with irreversible pulpitis. The performance of biomaterials such CEM cement may assist in the shift towards more biologic treatments. CLINICAL RELEVANCE: VPT/CEM may be a realistic alternative treatment for human mature molar teeth with symptoms of irreversible pulpitis; the use of VPT/CEM is highly beneficial for patients as well as general dentists.

Association between Clinical Symptoms and Histological Features of Molars with Acute Pulpitis.

Introduction: Diagnosis of dental pulp status on the basis of clinical signs in many cases helps clinicians to better resolve patient problems. Various studies have shown no correlation between clinical and histologic findings. The aim of the present study was to evaluate the associations between clinical findings and histological features in extracted decayed teeth with acute pulpitis. Materials and Methods: One hundred permanent cavitated human teeth with mature apices and pulpitis, which were extracted for reasons not related to the present study, were evaluated. Demographic, clinical, and radiographic data were collected using pre-designed questionnaires. After tooth extraction, 5 micron-thick slices were prepared for microscopic assessment. General pathologist evaluated reactions to stimuli in all areas of the pulp tissue under a light microscope. When present, inflammation was classified according to the type and spread of cell detected and other histological findings, such as abscess formation, pulp stones, and pulpal fibrosis, were also recorded. Results: We found significant associations between pain characteristics, such as pain type and duration, and histological status. Acute inflammation, severe chronic inflammation, and liquefactive necrosis increased with pain severity. Various histological sections showed the absence of pulpal inflammation. Conclusions: We found a good agreement of patients' pain histories and pain characteristics with histological pulp status. Thus, the use of specified CHARTs and SCALEs that help patients provide the most accurate responses to questions about pain would aid the diagnosis of pulp status. In cases with an accurate pulpal diagnosis, the clinicians can manage pulpal protection when it is possible.

Clinical and radiographic evaluation of vital pulp therapy in open apex teeth with MTA and ZOE.

The purpose of this study was to report the success rate of using mineral trioxide aggregate (MTA) and zinc oxide eugenol (ZOE) as vital pulp therapy agents in immature permanent teeth with carious or traumatic pulp exposure. Subjects were children with permanent teeth requiring pulpotomy (apexogenesis) and without systemic diseases. Both ZOE and MTA treatments as pulpotomy agents showed clinical and radiographic success in immature permanent teeth. Although MTA was more successful, it is more expensive, and dentin bridges may develop over canal orifices, complicating future root canal therapy.

Effects of two antioxidants on the microleakage of resin-based composite restorations after nonvital bleaching.

AIM: The aim of this study was to compare the neutralizing effect of antioxidant agents on the microleakage of dental restorations in nonvital teeth after bleaching with carbamide peroxide. Also assessed was the correlation of the microleakage data between an electrochemical and a staining technique. METHODS AND MATERIALS: Following root canal therapy, 40 sound and similar human maxillary central incisors were randomly divided into four groups of 10 specimens each (n=10). The groups were subjected to one of four treatments: Group 1, bleaching with 10 percent carbamide peroxide for periods of eight hours per day for one week without an antioxidant agent; Group 2, bleaching with 10 percent carbamide peroxide plus 10 percent sodium ascorbate gel; Group 3, bleaching with 10 percent carbamide peroxide plus 10 percent sodium ascorbate gel combined with a surfactant; and Group 4, no bleaching treatment (control group). In all groups, the access cavities were restored using the Single Bond Plus Adhesive system and Z100 resin-based composite. After 1,000 thermal cycles, the teeth were dried and three layers of nail varnish were applied over the entire surface area to within 1.0 mm of the restoration. A PVC-covered copper wire, with 3.0 mm of exposed bare wire, was inserted apically 5.0 mm into the canal, which was obturated with gutta-percha and sealed with sticky wax and varnish at the apex. Leakage was continuously monitored for 40 days using a conductimetric method. The teeth were immersed in 0.5 percent basic fuchsine for 24 hours, followed by sectioning for microscopic examination at 16x magnification. The data were analyzed using ANOVA and the Newman-Keuls multiple comparison, Kruskal-Wallis, Mann-Whitney, and Spearman's rho tests (p<0.05). RESULTS: Based on the electrochemical results, cavities subjected to 10 percent sodium ascorbate gel combined with a surfactant displayed the least amount of microleakage while teeth that were bleached but not treated with an antioxidant exhibited significantly greater microleakage (p=0.007). These findings also were corroborated by the results of the staining experiments that showed a strong correlation between the electrochemical and staining findings (p=0.006) for the groups. CONCLUSION: After nonvital bleaching and the application of the antioxidant 10 percent sodium ascorbate, the addition of the surfactant 0.2 percent Tween 80 to the conventional antioxidant formulation significantly reduced microleakage. CLINICAL SIGNIFICANCE: The addition of a surfactant to the antioxidant formulation significantly reduced microleakage when it was applied after bleaching.

Treatment of a two-canal maxillary lateral incisor.

Recognition of the complexity of root canals and multiple root canals that may vary for any type of tooth is necessary for long-term successful endodontic therapy. This article describes a maxillary lateral incisor with two canals. This case is unusual because considerable research has reported that these teeth can only have a single canal.

Intratubular Enterococcus faecalis viability assessment following root canal instrumentation with rotary and reciprocating systems via fluorescence microscopy.

Background. The present in vitro study aimed to compare the effectiveness of the WaveOne and ProTaper Gold systems in removing the Enterococcus faecalis biofilm. Methods. Thirty-eight mandibular premolars were selected. The root canals were assigned to standard control (canals serially enlarged with ProTaper Gold S1-S2-F1-F2, n=15) and experimental (canals enlarged with Primary WaveOne file, n=15) groups. Following the instrumentation procedure, the root canals underwent a sampling procedure, and the colonyforming unit (CFU) counts were determined. The samples were also evaluated under a fluorescent microscope to evaluate viable bacteria. The data were analyzed using independent samples t test and paired samples t test. Results. The results showed that, compared with the ProTaper group, the WaveOne group exhibited the least viable bacteria (P =0.004). Conclusion. It was concluded that comparison with the ProTaper Gold rotary system, the WaveOne reciprocating file is more successful in reducing intratubular viable bacteria counts.

MTA pulpotomy of human permanent molars with irreversible pulpitis.

The histological success of mineral trioxide aggregate (MTA) pulpotomy for treatment of irreversible pulpitis in human teeth as an alternative treatment was investigated in this study. Fourteen molars which had to be extracted were selected from patients 16-28 years old. The selection criteria include carious pulp exposure with a history of lingering pain. After isolation, caries removal and pulp exposure, MTA was used in pulpotomy treatment. Patients were evaluated for pain after 24 h. Two patients were lost from this study. Twelve teeth were extracted after 2 months and were assessed histologically. Recall examinations confirmed that none of the patients experienced pain after pulpotomy. Histological observation revealed that all samples had dentin bridge formation completely and that the pulps were vital and free of inflammation. Although the results favour the use of MTA as a pulpotomy material, more studies with larger samples and a longer recall period are suggested to justify the use of MTA for treatment of irreversible pulpitis in human permanent teeth.

The Effectiveness of Sonic-Activated Irrigation in Reducing Intratubular Enterococcus faecalis.

Introduction: The purpose of this in vitro study was to compare the effectiveness of sonic activation and syringe irrigation of 5.25% sodium hypochlorite in removing the Enterococcus faecalis (E. faecalis) biofilm. Methods and Materials: Root canals of 54 extracted human single-rooted central incisors were prepared with ProTaper S1-S2-F1-F2 and Gates Gliden burs size 1, and 2 at the working length. After sterilization, the root canals were contaminated with E. faecalis suspension and randomly assigned to three groups: G1, conventional syringe irrigation; G2, sonic agitation of NaOCl with Endo Activator system; and G3, no subjected to the mentioned irrigation techniques (negative control). Canals were sampled after the disinfection procedure. The colony forming units (CFU) count was evaluated. Samples were also visualized under fluorescent microscope to count viable bacteria. Data were statistically analyzed using the Kruskal-Wallis and one-way ANOVA followed by Tukey's test (P<0.05). Results: There was a significant reduction in the CFU count after both irrigation techniques. There was no significant difference between two techniques (P=0.874). Using bacterial viability kit, Endo Activator displayed the least viable bacteria than the other groups (P<0.001) and control group showed the greatest one (P<0.001). Conclusion: In this in vitro study, the Endo Activator system was more successful in reducing intratubular viable bacteria compared with NaOCl syringe irrigation alone.

Efficacy of IANB and Gow-Gates Techniques in Mandibular Molars with Symptomatic Irreversible Pulpitis: A Prospective Randomized Double Blind Clinical Study.

INTRODUCTION: The aim of the present study was to compare the efficacy of the inferior alveolar nerve block (IANB) and Gow-Gates techniques in mandibular molars with symptomatic irreversible pulpitis. METHODS AND MATERIALS: In this randomised, double-blind clinical trial, 80 patients referred to Mashhad Dental School, were randomly divided into two groups: IANB and Gow-Gates anaesthetic techniques using 2% lidocaine with 1:100000 epinephrine. After injection, if pain during caries/dentin removal and access cavity preparation was reported in each group, the patients once again were randomly allocated to receive buccal or lingual supplementary infiltration. Pain severity was evaluated using a visual analogue scale. The rates of positive aspiration and changes in heart rate were compared between the IANB and Gow-Gates. Paired and individual t-tests and the Mann-Whitney U-test were used to compare the reduction in pain severity. The level of significance was set at 0.05. RESULTS: The success rates of anaesthesia in the Gow-Gates and IANB techniques were 50% and 42.5%, respectively with no significant difference (P=0.562). Supplementary infiltrations significantly reduced pain severity in all subgroups (P<0.05). Lingual infiltration resulted in a significantly greater reduction in pain severity in the IANB group than in the Gow-Gates group (P<0.05). No significant difference in heart rate or positive aspiration results was observed between groups (P>0.05). CONCLUSIONS: In the present study, the efficacy of the IANB and Gow-Gates techniques was comparable in mandibular molars with symptomatic irreversible pulpitis. Supplementary buccal and lingual infiltration significantly reduced pain severity.

Mandibular first molar with four distal canals.

A mandibular first molar with more than four canals is an interesting example of anatomic variations, especially when four of these canals are located in distal roots. This report describes a case of a mandibular first molar with six canals (two mesial and four distal canals in two distal roots). The canals were equipped with a K-file and irrigated with NaOCl (5.25%) and normal saline as the final irrigant. The canals were filled laterally with gutta percha and AH26 sealer (De Trey, Dentsply, Switzerland). This case shows a rare anatomic configuration and points out the importance of looking for additional canals.

An evaluation of microbial leakage after using MTAD as a final irrigation.

Cleaning the root canal is not possible without using proper irrigation. The aim of this in vitro study was to evaluate the effect of MTAD as a final irrigant on bacterial leakage of the root canal, and its interaction with two conventional root canal sealers. We used 132 extracted human maxillary anterior teeth. The teeth were randomly divided into three experimental groups (n=40) and two groups (n=6) of positive and negative control. In group 1, the smear layer was not removed and irrigation was performed using 5.25% NaOCl. In group 2, the smear layer was removed using EDTA, and in group 3, the smear layer was removed using MTAD according to the clinical protocol of use. The teeth in each group were obturated with gutta-percha and AH-Plus or Rickert sealer. The coronal portion of each root was placed in contact with inoculum of Streptococcus mutans in Brain Heart Infusion (BHI) culture media. Each root tip was placed in one bottle containing sterile BHI. Mean duration of bacterial penetration in groups 2 and 3 was significantly greater than in group 1, but there was no significant difference between groups 2 and 3. According to our findings, it takes longer for bacteria to penetrate when either EDTA or MTAD is used for smear layer removal. The root canals obturated with AH Plus showed significantly longer duration of resistance to bacterial penetration than canals obturated with Rickert.

Clinical and radiographic evaluation of root perforation repair using MTA.

An accident that can occur during endodontic treatment is perforation, which adversely affects the prognosis of the teeth. A restorative material should be easy to use, nonresorbable, biocompatible, esthetically pleasing, and should provide a complete seal. Mineral trioxide aggregate (MTA) is a relatively new material that is being used successfully to repair perforation. The purpose of this study was to perform a clinical and radiographical evaluation of the success rate of root perforation repairs using mineral trioxide aggregate. Based upon the results of this study, MTA is a suitable material for root perforation repair and can be used confidently.

Mandibular canine with two separated canals.

The aim of endodontic treatment is to eliminate infection from the root canal by cleaning and shaping. Multiple factors, such as a broken instrument or anatomical variations in root canals, lead to treatment failure. This article describes a mandibular canine with two canals and two foramina. It is presented here to raise awareness of the importance of an improved access cavity in detecting excess canals.

Endodontic treatment of maxillary central incisor with two roots. A case report.

The purpose of this article is to describe endodontic treatment of the central incisor with two roots. Radiographs show two distinct roots in the middle portion of the tooth.

Endodontic treatment of a supernumerary tooth fused to a mandibular second molar: a case report.

Since abnormal tooth morphology can predispose to caries and periodontal disease, careful management of fused teeth is essential. In this paper we report a rare case of a fused molar and supernumerary tooth and describe its management. Caries was removed from the tooth complex under local anesthesia. The pulp chamber of the supernumerary tooth was exposed without involvement of second molar pulp chamber. The root canal of the supernumerary tooth was prepared using the step back technique and copious irrigation with 2.6% sodium hypochlorite. Obturation using the lateral condensation technique with gutta-percha and AH26 sealer was subsequently performed and final restoration was accomplished with composite resin. Nine months after the treatment, no clinical or radiographic concern is apparent, and the second molar tooth has remained vital.