A comparative study on sealing ability of mineral trioxide aggregate, calcium enriched cement and bone cement in furcal perforations.

AIM: The aim of this study was to compare the bacterial leakage of mineral trioxide aggregate (MTA), calcium enriched cement (CEM), and bone cement (BC) as repair materials in furcal perforations. METHODS: The pulp chambers of 57 human mandibular molar teeth were accessed and the root canal orifices were located. The roots were horizontally sectioned in the middle third. Composite resin was used to fill the root canal orifices and the apical end of the roots. The 1 mm furcation perforations were performed in the center of the pulp chamber floor, using diamond fissure burs. Fifty one teeth were divided into 3 groups. Six teeth were used as controls. Perforation defects were repaired with either MTA, CEM, or BC. A bacterial leakage model utilizing phenol red with 3% lactose broth was used for evaluation. The upper pulp chambers were subsequently filled with 5µL bacterial suspension containing Enterococcus faecalis. Then the top of the assembly was covered with aluminum foil to avoid unintentional contamination. The entire apparatus was incubated at 37°C, and bacterial leakage was evaluated daily by checking the turbidity in the culture medium of the lower part of the chamber. The bacterial inoculation was renewed every day, for 30 days. Leakage was noted when color conversion of the culture media was observed and was statistically analyzed using the Chi-square test with significance set at P< 0.05. RESULTS: Sixteen (94%) of the 17 samples of the MTA group, thirteen (81%) of the 17 samples of the CEM group and sixteen (94%) of the 17 samples in BC group were fully contaminated at 30 days. There was no statistically significant difference between the three study groups (P>0.05). CONCLUSION: According to the present study, in teeth with furcation perforations, the coronal seal produced by MTA preparations was equally to that produced by CEM cement and Bone cement.

RNA interference-mediated silencing of Atp6i prevents both periapical bone erosion and inflammation in the mouse model of endodontic disease.

Dental caries is one of the most prevalent infectious diseases in the United States, affecting approximately 80% of children and the majority of adults. Dental caries may lead to endodontic disease, where the bacterial infection progresses to the root canal system of the tooth, leading to periapical inflammation, bone erosion, severe pain, and tooth loss. Periapical inflammation may also exacerbate inflammation in other parts of the body. Although conventional clinical therapies for this disease are successful in approximately 80% of cases, there is still an urgent need for increased efficacy of treatment. In this study, we applied a novel gene-therapeutic approach using recombinant adeno-associated virus (AAV)-mediated Atp6i RNA interference (RNAi) knockdown of Atp6i/TIRC7 gene expression to simultaneously target periapical bone resorption and periapical inflammation. We found that Atp6i inhibition impaired osteoclast function in vitro and in vivo and decreased the number of T cells in the periapical lesion. Notably, AAV-mediated Atp6i/TIRC7 knockdown gene therapy reduced bacterial infection-stimulated bone resorption by 80% in the mouse model of endodontic disease. Importantly, Atp6i(+/-) mice with haploinsufficiency of Atp6i exhibited protection similar to that in mice with bacterial infection-stimulated bone erosion and periapical inflammation, which confirms the potential therapeutic effect of AAV-small hairpin RNA (shRNA)-Atp6i/TIRC7. Our results demonstrate that AAV-mediated Atp6i/TIRC7 knockdown in periapical tissues can inhibit endodontic disease development, bone resorption, and inflammation, indicating for the first time that this potential gene therapy may significantly improve the health of those who suffer from endodontic disease.

Experimental gel containing bioactive glass-ceramic to minimize the pulp damage caused by dental bleaching in rats.

OBJECTIVES: This study evaluated if the use of a bioactive glass-ceramic-based gel, named Biosilicate (BS), before, after or mixed with bleaching gel, could influence the inflammation of the dental pulp tissue of rats' molars undergoing dental bleaching with hydrogen peroxide (H2O2). METHODOLOGY: The upper molars of Wistar rats (Rattus norvegicus, albinus) were divided into Ble: bleached (35% H2O2, 30-min); Ble-BS: bleached and followed by BS-based gel application (20 min); BS-Ble: BS-based gel application and then bleaching; BS/7d-Ble: BS-based gel applications for 7 days and then bleaching; Ble+BS: blend of H2O2 with BS-based gel (1:1, 30-min); and control: placebo gel. After 2 and 30 days (n=10), the rats were euthanized for histological evaluation. The Kruskal-Wallis and Dunn statistical tests were performed (P<0.05). RESULTS: At 2 days, the Ble and Ble-BS groups had significant alterations in the pulp tissue, with an area of necrosis. The groups with the application of BS-based gel before H2O2 had moderate inflammation and partial disorganization in the occlusal third of the coronary pulp and were significantly different from the Ble in the middle and cervical thirds (P<0.05). The most favorable results were observed in the Ble+BS, which was similar to the control in all thirds of the coronary pulp (P>0.05). At 30 days, the pulp tissue was organized and the bleached groups presented tertiary dentin deposition. The Ble group had the highest deposition of tertiary dentin, followed by the Ble-BS, and both were different from control (P<0.05). CONCLUSION: A single BS-based gel application beforehand or BS-based gel blended with a bleaching gel minimize the pulp damage induced by dental bleaching.

Effect of Preoperative Corticosteroids in Patients with Symptomatic Pulpitis on Postoperative Pain after Single-visit Root Canal Treatment: A Systematic Review and Meta-analysis.

INTRODUCTION: This study addressed the following population, intervention, comparator, outcome, timing, study design and setting question: in patients with preoperative pain who undergo single-visit nonsurgical endodontic treatment, what is the comparative efficacy of corticosteroids compared with other analgesics or placebo in reducing postoperative pain and the incidence of adverse events. METHODS: Database/electronic searches were conducted using the PubMed/MEDLINE, Scopus, and Cochrane databases to identify published articles using included key words in various combinations. Manual searching of articles was performed, and the Clinicaltrials.gov site was also searched. Two independent reviewers assessed eligibility for inclusion, extracted data, and assessed quality using the risk of bias tool. Where applicable, meta-analysis was conducted on the pooled effect size. RESULTS: The database search identified 481 citations and 37 citations through the manual search. After removing duplicates and going through abstracts, 28 full-text articles were perused. Five articles met the inclusion criteria; qualitative analysis revealed 4 studies had unclear risk of bias, and 1 study had low risk of bias. Only 1 study had a sizable sample size; the others had lesser sample sizes. Meta-analysis showed that prednisolone administered preoperatively was able to reduce the incidence of postoperative pain at 6, 12, and 24 hours. The patients in the studies reported no adverse effects. CONCLUSIONS: Corticosteroids may be more effective than placebo for the relief of postoperative endodontic pain in patients with symptomatic pulpitis undergoing single-visit root canal treatment. However, more studies need to be conducted with greater sample sizes to validate the conclusions.

In Vivo Study of the Action of a Topical Anti-Inflammatory Drug In Rat Teeth Submitted To Dental Bleaching.

Bleaching gel containing hydrogen peroxide (H2O2) cause damages in pulp tissue. This study investigated the action of a topical anti-inflammatory, the Otosporin®, in rats' bleached teeth with the null hypothesis of which the Otosporin® is no able to minimize the pulp inflammation that bleaching gel generates. The rat's molars were divided into groups: BLE: bleached (35% H2O2 concentration /single application of 30 min); BLE-O: bleached followed by Otosporin® (10 min); and control: placebo gel. In the second day after dental bleaching, the rats were killed, and the jaws were processed for hematoxylin-eosin and immunohistochemistry analysis for tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-17. The data collected were subjected to Kruskal-Wallis and Dunn statistical tests with at a 5% level of significance (p<0.05). The BLE group had moderate to strong inflammation in the occlusal third of the coronary pulp, with necrotic areas; and BLE-O, mild inflammation (p<0.05). There was a significant difference in the occlusal and middle thirds of the coronary pulp between the BLE with BLE-O and control groups (p<0.05). There was no difference in the cervical third (p>0.05). The BLE group had a high immunoexpression of TNF-α than BLE-O and control groups (p<0.05), with moderate and mild immunoexpression, respectively. Regarding IL-6 and IL-17, the BLE group had higher immunoexpression than control (p<0.05); the BLE-O was similar to the control (p>0.05). The topical anti-inflammatory Otosporin® can reduce pulp inflammation after dental bleaching in the rat teeth.

Zinc oxide eugenol and Endoflas pulpectomy in primary molars: 24-month clinical and radiographic evaluation.

CONTEXT: Despite modern advancement in material and technical aspect, management of infected primary molars is of prime concern in pediatric endodontics. An effective root canal material plays the major role in achieving the fluid impervious seal by defending against variant microflora and maintaining the tooth in function for longer duration. AIMS: This study aims to evaluate and compare the success of endoflas as root canal filling material in infected primary molars with zinc oxide eugenol (ZOE). MATERIALS AND METHODS: Primary molars with necrotic pulp in healthy, cooperative children were selected. Ethical clearance and informed consent was obtained. Standardized pulpectomy procedure was done and root canals were filled with either ZOE or endoflas. Further follow-up with clinical and radiographic evaluation was carried at 0, 3, 6, 12, and 24 months. The findings obtained were statistically analyzed using Chi-square test. RESULTS: Endoflas showed acceptable results as root canal filling material in primary molars even at 2-year follow-up, though overfilling of root canals led to low success rate compared to teeth with combined optimal and under fillings. There was no significant difference between the two materials (P > 0.05). CONCLUSIONS: Endoflas could be a potential alternative to ZOE for preserving infected primary molars.

Pulp-dentine complex changes and root resorption during intrusive orthodontic tooth movement in patients prescribed nabumetone.

Pulpitis, external root resorption, and pain may be experienced during orthodontic movement. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been suggested to control these changes. The purpose of this study was to observe pulp-dentinal reactions, root resorption, tooth pain, and tooth movement after the application of a 4-ounce intrusive orthodontic force to human maxillary first premolars in patients given the NSAID nabumetone. Thirty-four maxillary first premolars were evaluated. A placebo was prescribed to 17 patients after an intrusive force was activated and reactivated for an 8-week period on the right side. The same procedure was repeated on the left side after patients were given nabumetone. Pulp-dentinal reactions and external root resorption were evaluated by histology. Pain and movement were also evaluated. Nabumetone was found to be useful in reducing pulpitis, external root resorption, and pain caused by intrusive orthodontic movement, without altering tooth movement in response to the application of orthodontic force.

[Pain during and after root canal treatment]. / Bestrijding van pijn bij de wortelkanaalbehandeling.

Toothache can be prevented or remedied with a root canal treatment. Unfortunately a root canal treatment can also be the cause of pain. During a root canal treatment pain can be suppressed by local anesthesia, the use of the airotor, the attitude of the dentist and his communication with the patient. Afterpain has three causes: damage and iatrogenic apical periodontitis, pulpitis and continuing apical periodontitis. In this article the possible treatment of pain by a root canal treatment are extensively discussed.

Rethinking root canal treatment: understanding the difference between preventing and treating endodontic infection.

Root canal treatment is a frequently performed procedure aimed to address pulpal and peri-radicular disease. It comprises a number of clinical steps regardless of the initial diagnosis. The emphasis of each step varies according to whether there is a vital pulp (non-infected) or if the pulp system contains necrotic, infected tissue and there is peri-apical pathology. This article aims to discuss the differences in performing root canal treatments on teeth with vital and non-vital pulps. The reader should understand the differences between performing a root canal treatment in teeth with vital pulps and those with infected root canal spaces and peri-radicular pathology.

Experimental gel containing bioactive glass-ceramic to minimize the pulp damage caused by dental bleaching in rats

Abstract Objectives This study evaluated if the use of a bioactive glass-ceramic-based gel, named Biosilicate (BS), before, after or mixed with bleaching gel, could influence the inflammation of the dental pulp tissue of rats' molars undergoing dental bleaching with hydrogen peroxide (H2O2). Methodology The upper molars of Wistar rats (Rattus norvegicus, albinus) were divided into Ble: bleached (35% H2O2, 30-min); Ble-BS: bleached and followed by BS-based gel application (20 min); BS-Ble: BS-based gel application and then bleaching; BS/7d-Ble: BS-based gel applications for 7 days and then bleaching; Ble+BS: blend of H2O2 with BS-based gel (1:1, 30-min); and control: placebo gel. After 2 and 30 days (n=10), the rats were euthanized for histological evaluation. The Kruskal-Wallis and Dunn statistical tests were performed (P<0.05). Results At 2 days, the Ble and Ble-BS groups had significant alterations in the pulp tissue, with an area of necrosis. The groups with the application of BS-based gel before H2O2 had moderate inflammation and partial disorganization in the occlusal third of the coronary pulp and were significantly different from the Ble in the middle and cervical thirds (P<0.05). The most favorable results were observed in the Ble+BS, which was similar to the control in all thirds of the coronary pulp (P>0.05). At 30 days, the pulp tissue was organized and the bleached groups presented tertiary dentin deposition. The Ble group had the highest deposition of tertiary dentin, followed by the Ble-BS, and both were different from control (P<0.05). Conclusion A single BS-based gel application beforehand or BS-based gel blended with a bleaching gel minimize the pulp damage induced by dental bleaching.

Prophylactic treatment of dens evaginatus using mineral trioxide aggregate.

Two case reports with dens evaginatus are presented. Each patient had one tooth affected. There was a prominent tubercle on the occlusal surface of the mandibular second premolar. Under local anesthesia and rubber dam isolation a partial pulpotomy was conducted and mineral trioxide aggregate was placed. After 6 months the teeth were removed as part of planned orthodontic treatment. Histological examination of these teeth showed an apparent continuous dentin bridge formation in both teeth, and the pulps were free of inflammation. These cases show that mineral trioxide aggregate can be used as an alternative to existing materials in the proplylactic treatment of dens evaginatus.

Pulpal inflammatory responses following non-carious class V restorations.

The effects of inflammatory activity following surgical intervention can injure pulp tissues; in severe cases it can lead to pulpal complications. With this article, the authors report on the effects of cavity preparation and restoration events and how they can interact together to reduce or increase the severity of pulpal inflammatory activity in 202 restored Class V cavities. Although some inflammatory activity was observed in the absence of bacteria, the severity of pulpal inflammatory activity was increased when cavity restorations became infected. Zinc oxide eugenol and resin-modified glass ionomer cement prevented bacterial microleakage in cavity restorations, with no severe inflammatory activity observed with these materials. Bacteria were observed in cavities restored with enamel bonding resin and adhesive bonded composites and were associated with severe grades of inflammatory activity. The cavity remaining dentin thickness influenced the grade of inflammatory activity. In the absence of infection, the grade of inflammatory activity decreased after 20 weeks post-operatively. In the presence of infection, the grade of pulpal inflammation remained stable until a minimum of 30 weeks had elapsed.

Evaluation and treatment of bacterial microleakage.

Recent data have shown a correlation between pulp response and material biocompatibility when microleakage is prevented. Considering vital dentin, the dentist must keep in mind that it is an extension of the pulp, presenting the first line of response to the consequences of microleakage. Healing of the dental pulp is ensured when a clinical seal is provided to prevent bacterial microleakage. Microleakage is a biological phenomenon with several important clinical implications. The affective component clinically presents as dentin postoperative hypersensitivity due to the episodic hydrodynamic fluid movement within the tubule complex. The effective component is the disease process which signals the dentin and pulp complex to respond by deposition of sclerotic and reparative dentin deposition. Uncontrolled microleakage generally produces patient pain as well as to later allow bacterial infection resulting in recurrent caries and pulp inflammation. The dynamic, permeable nature of the dentin interface allows residual bacteria to proliferate following cavity preparation. Following sterile operative procedures, bacteria have been shown to percolate into the cavosurface margin resulting in recurrent caries and pulp inflammation. This report considers biological data emphasizing the clinical necessity to provide a hermetic seal to prepared dentin to prevent both dentin hypersensitivity and pulp inflammation.

Keeping the pulp alive: the pharmacology and toxicology of agents applied to dentine.

Materials applied to teeth release chemicals which may diffuse through dentine to either harm or help the dental pulp. Chemical threats are minimized by material choice or by using relatively impermeable lining or base materials which are themselves of low chemical toxicity. The most probable long-term threat to the pulp in the restored tooth is bacterial, through leakage around restorations. This may be prevented by the use of treatment sequences designed to develop an effective seal. Pulpal inflammation is treated primarily by removal of the irritant cause; inflammation may also be suppressed in the very short term by corticosteroids, and its resolution aided in the longer term by zinc oxide-eugenol preparations.

Antibiotics and endodontics.

Antibiotics can be used as an adjunct to endodontic treatment in a number of ways--locally, systemically and prophylactically. The local or intra-canal use of antibiotics in the form of medicaments is common. However, the commercially available agents for this purpose may not be the ideal mixtures. Systemic antibiotics should be restricted to patients who have local signs of infection, malaise and elevated body temperature. Prophylactic use of antibiotics has been recommended for patients 'at risk' of infective endocarditis, in some pre-surgical situations and following avulsion and replantation of teeth. The tendency towards indiscriminate antibiotic use should be discouraged. The use of broad spectrum drugs should be restricted so that these medications remain effective in serious situations.

Dentin adhesive superior to copal varnish in preventing microleakage in primary teeth.

Microleakage presents a major challenge to the success of all restorations placed in the oral cavity, resulting in postoperative sensitivity, pulpal irritation, and secondary caries formation. The objective of this study was to evaluate the effects of an adhesive cavity liner under amalgam restorations in primary teeth. Sixty class V amalgam restorations were placed on the buccal and/or lingual surfaces of 38 primary molars and canine teeth. A dentin adhesive cavity liner was placed under 20 of the amalgam restorations. Another 20 restorations were lined with copal cavity varnish prior to amalgam condensation. The remaining 20 had no liner. All teeth were thermocycled in 0.5% basic fuschin dye, sectioned, and examined under a stereomicroscope to evaluate microleakage. While all specimens demonstrated leakage around the margins of the restorations, only the teeth with adhesive resin liners prevented leakage into the dentinal walls of the restoration. The copal cavity varnish group displayed microleakage approaching the pulpal chamber, whereas the unlined specimens consistently displayed dye penetration into the pulp chamber. At P < 0.01, the use of an adhesive cavity liner under amalgam restorations in primary teeth resulted in significantly less microleakage.

Pulpal injury: pathology, diagnosis and periodontal reactions.

Diagnosis of pulpal disease can be difficult due to the lack of diagnostic signs and symptoms available to the practitioner. An understanding of the possible underlying pathological processes, combined with an exact assessment of the pain history, and appropriate clinical tests, should aid the practitioner in determining the nature of pulpal inflammation, and differentiating it from dentine sensitivity and cracked teeth. The responses of the pulp to traumatic injury to the periodontal membrane (PDM) require special consideration, particularly with respect to the assessment of pulp vitality, and the determination of cases requiring pulp extirpation in order to avoid inflammatory root resorption. Although the pulp is relatively isolated from the rest of the dentoalveolar complex by a dentine/cementum barrier, it is important to remember that it can communicate with the PDM through apical and lateral foramina, and areas of damaged cementum. Hence, it is a priority to both preserve the integrity of the cemental layer in cases of traumatic injury and periodontal disease, and to prevent the inflammation and resorption associated with periapical lesions by accurate diagnosis of irreversible pulpitis and pulp necrosis, followed by appropriate endodontic debridement procedures.

Saving pulps--a biological basis. An overview.

AIM: Cavity preparation and restoration variables have an uncertain relationship to pulp injury and repair responses. The purpose of this paper is to determine the importance of cavity preparation and restoration variables, by ranking them according to their effect on pulp injury (odontoblast survival) and pulp repair (reactionary dentine secretion). METHOD: The seven studies reviewed are all based on the protocols described by Murray, Smith and colleagues in 2000 and 2001. RESULTS: The studies reviewed provide new perspectives on the importance of cavity preparation and restoration variables in mediating pulp activity. CONCLUSIONS: The onset of post-operative complications may be most productively minimised by focusing practitioner attention to aspects of treatment highlighted in this review.

Luxation injuries and external root resorption--etiology, treatment, and prognosis.

When a tooth sustains a luxation injury, attachment damage of varying degrees will occur. In addition, necrosis of the pulp might result, thereby making the pulp space susceptible to infection. These circumstances can lead to root resorption. Treatment for root resorption includes preventing it by avoiding causes of root surface injury, minimizing initial inflammation, and reversing resorption.