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.

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.

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.

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.

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.

Human Pulp Response to Direct Pulp Capping and Miniature Pulpotomy with MTA after Application of Topical Dexamethasone: A Randomized Clinical Trial.

INTRODUCTION: The aim of this randomized clinical trial was to compare the histologic pulp tissue response to one-step direct pulp capping (DPC) and miniature pulpotomy (MP) with mineral trioxide aggregate (MTA) after application of dexamethasone in healthy human premolars. METHODS AND MATERIALS: Forty intact premolars from 10 orthodontic patients, were randomly chosen for DPC (n=20) or MP (n=20). In 10 teeth from each group, after exposure of the buccal pulp horn, topical dexamethasone was applied over the pulp. In all teeth the exposed/miniaturely resected pulp tissue was covered with MTA and cavities were restored with glass ionomer. Teeth vitality was evaluated during the next 7, 21, 42, and 60 days. Signs and/or symptoms of irreversible pulpitis or pulp necrosis were considered as failure. According to the orthodontic schedule, after 60 days the teeth were extracted and submitted for histological examination. The Kruskal-Wallis and Fisher's exact tests were used for statistical analysis of the data (P=0.05). RESULTS: Although dexamethasone specimens showed less inflammation, calcified bridge, pulpal blood vasculature, collagen fibers and granulation tissue formation were not significantly different between the groups (P>0.05). CONCLUSION: Topical dexamethasone did not hindered pulp healing but reduced the amount of underlying pulpal tissue inflammation after DPC and MP in healthy human premolars.

Choice of Treatment Plan Based on Root Canal Therapy versus Extraction and Implant Placement: A Mini Review.

Case selection and treatment plan are important aspects of endodontic treatment. Dentists should organize the treatment plan based on their knowledge, abilities, skills and more importantly the patients' preference and dentition. Indubitably, the treatment plan for each patient is exclusive and "tailor-made" and cannot be used for all patients. Dentists' selfestimation of their abilities opens up treatment options; however, in difficult or complicated cases it is advisable to refer to a specialist. Currently, one of the most challenging aspects in dentistry is the choice between extraction and placement of implant (EPI) instead of a complicated root canal treatment (RCT). Overemphasis on one treatment plan while neglecting other options, not only mislead the dentist but also impose unnecessary charges to the patients. This mini-review compares RCT to EPI from various aspects to help practitioners in routine decision making.

A review on vital pulp therapy in primary teeth.

Maintaining deciduous teeth in function until their natural exfoliation is absolutely necessary. Vital pulp therapy (VPT) is a way of saving deciduous teeth. The most important factors in success of VPT are the early diagnosis of pulp and periradicular status, preservation of the pulp vitality and proper vascularization of the pulp. Development of new biomaterials with suitable biocompatibility and seal has changed the attitudes towards preserving the reversible pulp in cariously exposed teeth. Before exposure and irreversible involvement of the pulp, indirect pulp capping (IPC) is the treatment of choice, but after the spread of inflammation within the pulp chamber and establishment of irreversible pulpitis, removal of inflamed pulp tissue is recommended. In this review, new concepts in preservation of the healthy pulp tissue in deciduous teeth and induction of the reparative dentin formation with new biomaterials instead of devitalization and the consequent destruction of vital tissues are discussed.

Anterior traumatic dental injuries in East Iranian school children: prevalence and risk factors.

INTRODUCTION: The aim of this cross-sectional study was to determine the prevalence and etiology of traumatic dental injuries (TDI) in school children of the Northeast of Iran. The type of involved teeth, the place of injury and treatment quality as well as the relationship between TDI and anatomic predisposing factors such as overjet and lip coverage were evaluated. METHODS AND MATERIALS: A total of 778 school children were clinically examined for signs of trauma to their permanent teeth and the amount of overjet and lip coverage were also recorded. A questionnaire containing demographic data of participants and history of the dental trauma was given to the children's parents. The data were analyzed using the chi-square and Mann-Whitney tests. RESULTS: One hundred and seventy eight (22.9%) children had a history of previous trauma to their permanent teeth. There was a significant difference between boys and girls (P=0.017). A total of 46.1% of children had experienced luxation injuries of permanent teeth, 37% had crown fractures, and 16.9% experienced avulsion of anterior teeth. Maxillary central incisors were the most commonly affected teeth (84%). There was a significant relationship between TDI and overjet (P=0.02) in permanent teeth. On the other hand, there was no statistically significant relationship between TDI and lip coverage. The most common cause of TDI was falling over (42.9%) followed by fighting (34%). The majority of traumas happened at home (46.8%) and school (29.9%). Sixty two (39.7%) children with TDI did not receive any dental or medical care after injury. CONCLUSION: The prevalence of dental trauma in school children in Iran was rather high (22.9%); the most common type of trauma to the permanent teeth was luxation injuries.

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.

Genotoxicity and cytotoxicity of mineral trioxide aggregate and calcium enriched mixture cements on L929 mouse fibroblast cells.

Mineral trioxide aggregate (MTA) has shown good biocompatibility in several studies. In the present study, the genotoxic and cytotoxic effects of calcium enriched mixture (CEM) were evaluated compared with MTA using MTT and single-cell gel (comet) assays with serial ascending concentrations (0 to 1,000 µg/mL) of tested materials. Cytotoxicity data indicated that there is no significant difference between CEM and MTA at all concentrations except for the full concentration (1,000 µg/mL); CEM had lower cytotoxicity. Genotoxic effects were more evident with CEM at concentrations of 15.6 and 250 µg/mL; however, was less than that of MTA at concentrations of 500 and 1,000 µg/mL. The cytotoxicity and genotoxicity effects of the two experimental groups generally increased with consistency. Under the conditions of this study, CEM is biocompatible in terms of cyto- and genotoxicity. It appears to be an alternative to MTA as an endodontic biomaterial offering several advantages.

New approaches in vital pulp therapy in permanent teeth.

Vitality of dental pulp is essential for long-term tooth survival. The aim of vital pulp therapy is to maintain healthy pulp tissue by eliminating bacteria from the dentin-pulp complex. There are several different treatment options for vital pulp therapy in extensively decayed or traumatized teeth. Pulp capping or pulpotomy procedures rely upon an accurate assessment of the pulp status, and careful management of the remaining pulp tissue. The purpose of this review is to provide an overview of new approaches in vital pulp therapy in permanent teeth.

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.

Residual dentin thickness of bifurcated maxillary premolars following two post space preparation methods.

INTRODUCTION: The aim of this in vitro study was to compare the effect of Gates-Glidden and Peeso reamer drills on residual dentin thickness during post space preparation in order to discover which method has minimum root structure damage. MATERIALS AND METHODS: Thirty extracted human maxillary premolars with bifurcations at root middle were horizontally cut 15 mm coronal to the apical end after root canal treatment. The samples were scannedby Cone Beam Computed Tomography (CBCT) before and after preparing the post space. Residual dentin thicknesses were measured at 4-, 6-, and 8-mm levels from the apex. Data were analyzed using repeated measured ANOVA. RESULTS: Endodontic therapy and post space preparations removed more dentin within the bifurcation of both roots compared to outer dentin. The difference in residual dentin thickness was highly significant regarding stage (before and after post space preparation) in all levels and stage × device in coronal and middle levels (P<.05). This in vitro study emphasizes the minimal dentin width in the buccal root of maxillary premolars, especially near the bifurcation. CONCLUSION: Lack of adequate residual dentin thickness after post space preparation implies that the use of posts in maxillary first premolars should be limited. When mandatory, it is recommended that post space be prepared with Gates-Glidden drill in the palatal root of maxillary first premolars and use of Peeso reamer be avoided.

Vital pulp therapy with three different pulpotomy agents in immature molars: a case report.

INTRODUCTION: This case report describes apexogenesis treatment of three molar teeth of an 8-year-old boy using three different pulpotomy agents. METHODS: Pulpotomy was performed on decayed immature molar teeth with established irreversible pulpitis and the remaining pulp was capped with either zinc oxide eugenol, ProRoot mineral trioxide aggregate or calcium-enriched mixture (CEM) cement. Teeth were restored with stainless steel crowns. RESULTS: Eighteen months clinical and radiographic follow-up revealed successful preservation of pulpal vitality with continued root development in all treated teeth. CONCLUSION: Based on this case report, CEM cement may be an alternative option for pulpotomy treatment of immature permanent molars.

The sealing ability of resilon and gutta-percha in severely curved root canals: an in vitro study.

OBJECTIVE: The aim of this study was to compare the apical seal of curved canals obturated with Resilon/Epiphany with gutta-percha/AH Plus. MATERIALS AND METHODS: Thirty-four extracted human mandibular molars with 25-40 degree canal curvature of the mesial root were selected for this study. After preparation, the mesiobuccal canals were obturated with gutta-percha and AH- Plus sealer (group G) or Resilon and Epiphany sealer (group R). Four specimens served as control. Microleakage was evaluated after passing 3 and 30 days using the fluid filtration technique. The data were analyzed statistically using parametric tests. RESULTS: In the 3-day evaluation, the mean microleakage in group R was significantly less than in group G (P< 0.05). After 30 days, there was no significant difference between the two groups (P> 0.05). In group G, the leakage values at the end of 30 days were significantly less than values at the end of 3 days. Although in group R the mean leakage decreased after 30 days, this reduction was not statistically significant. CONCLUSION: Resilon/Epiphany provided a better seal than gutta-percha/AH-Plus in severely curved root canals immediately after obturation, although with the passage of time, Resilon/Epiphany was equivalent to gutta-percha/AH Plus in sealing properties.

The frequency of medically compromised patients in endodontic offices in iran.

INTRODUCTION: As the result of epidemiological transition and aging of Iranian population, the frequencies of systemic diseases among patients in of need endodontic treatment has increased, especially within developed cities. However, there have been no concise reports of systemic diseases in Iranian patients. Based on this need, the present investigation was conducted to assess the frequency of systemic disease among patients referred to endodontic private practice in three main cities in Iran. MATERIALS AND METHODS: In a retrospective study, the frequency of systematic diseases were abstracted from the health records of patients who were referred to three private practices limited to endodontics in Kerman, Mashhad, and Tehran between 1994 to 2011. RESULTS: Overall, 15,413 records of patients were assessed. The patterns of systematic diseases among endodontic patients in these three cities were different. The overall frequency of systemic disease in Kerman was significantly higher than two other cities (Kerman: 55.03%, Mashhad: 24.32%, Tehran: 22.16%; P<0.001). The most commonly occurring diseases were cardiac disease, hypertension, allergy and neurological disorders. CONCLUSION: Since the number of endodontic patients with systematic diseases is considerably significant and varied, special training and educations for treatment of medically compromised patient should be considered at both post- and undergraduate training.

A case report of maxillary second molar with two palatal root canals and a furcal enamel pearl.

This case report presents an uncommon case of maxillary molar with two palatal root canals and an enamel pearl in the furcation area. The article discusses root canal complexities of maxillary second molars as well as possibility of coexisting anomalies in the region that makes radiographic interpretation difficult and compromises the success of endodontic treatment.