Influence of ethylenediaminetetraacetic acid irrigation on the regenerative endodontic procedure in an immature rat molar model.

AIM: To analyse the influence of ethylenediaminetetraacetic acid (EDTA) on the repair process in immature rat molars after a regenerative endodontic procedure (REP). METHODOLOGY: The lower first molars of 12 4-week-old Wistar rats underwent pulpectomy in the mesial root and were divided into the following groups: sodium hypochlorite (NaOCl; n = 6) - the mesial canals were irrigated with 2.5% NaOCl for 5 min, and NaOCl-EDTA (n = 6) - the canals were irrigated with 2.5% NaOCl, followed by 17% EDTA for 5 min each. After evoking bleeding using a size 10 K-file, the cavities were sealed. Three molars on the untreated side were randomly used as control (control-15 d; n = 3), and three molars from the other three rats untreated were used as immediate control (n = 3). After 15 days (NaOCl, NaOCl-EDTA and control-15 d groups) or immediately (control-immediate), the animals were euthanized, and the teeth were subjected to histologic evaluation of tissue regeneration and presence of collagen fibres. Mann-Whitney U-test was used (p < .05). RESULTS: The experimental groups had newly formed cementum-like tissue and increased root length and thickness. Half of the specimens in NaOCl-EDTA group showed apical foramen closure, whilst the NaOCl group had partial apical closure. The experimental groups showed inflammatory infiltrate extending mainly to the medium third of the root canal. These parameters were similar between experimental groups (p > .05). Newly formed connective tissue in the pulp space was significantly higher in the NaOCl-EDTA group than in NaOCl group (p < .05). Regarding the collagen fibres, the NaOCl-EDTA group had more collagen fibres in the root tip, but there was no significant difference compared to NaOCl group, and both groups showed greater amount of immature fibres in this area; in the centre of the apical third of root canal, there was equivalence between mature and immature fibres from both groups (p > .05). CONCLUSIONS: Ethylenediaminetetraacetic acid irrigation improved newly formed intracanal connective tissue after REP in immature molars of rats; however, EDTA did not influence cementum-like tissue formation, apical closure, inflammatory infiltrate and maturation of collagen fibres.

Endodontic guide for the conservative removal of a fiber-reinforced composite resin post.

Prosthetic dentistry involves functional and esthetic restoration. Some situations require the use of fiber-reinforced composite resin posts that help preserve restorations. However, if the initial treatment fails, a new endodontic intervention may be required for fiber-reinforced composite resin post removal. This procedure can be complex and challenging but can be facilitated with guided endodontics. This clinical report describes the use of a prototyped guide created with virtual planning for fiber-reinforced composite resin post removal. The guide improved patient safety, shortened the treatment time, and eliminated the need for a new restoration.

Comparison between immediate and delayed post space preparations: a systematic review and meta-analysis.

OBJECTIVES: This systematic review and meta-analysis compared the effects of immediate and delayed post space preparation on apical sealing. MATERIALS AND METHOD: Two independent authors conducted a systematic search (PubMed/Medline, Cochrane Library, and other databases, until February 2020) and a risk of bias evaluation. Only in vitro studies that compared the effects of immediate and delayed post space preparations on apical filling and adhesion of the post were eligible. RESULT: Of the 742 articles retrieved, 32 were included. Most of the studies used single-rooted human teeth and rotary files for root canal preparation, a single-cone technique for the filling protocol, and rotary instruments for post space preparation. Various delayed preparation times were evaluated: 8-72 h, 5-30 days (mainly 7 days), and 4 months. In nine studies, the delayed groups showed more apical leakage, while four studies reported more leakage in the immediate groups; ten studies found no significant difference. One study found more bacterial penetration in the delayed group, whereas three studies showed no significant difference. One study reported more voids in the delayed group, while another found no such difference. Three studies showed better post-bond strength in the delayed group, one in the immediate group, whereas three found no significant difference in post-bond strength. Three studies employing varied sealers for root canal fillings were considered for meta-analysis. Two subgroup analyses were also performed (one concerning the use of resin-based sealers (AH Plus), another for zinc oxide-eugenol-based sealers). The results of the meta-analysis showed that a delayed post space preparation led to a significantly higher apical leakage than an immediate preparation (mean difference = 0.41 mm, confidence interval = 0.24-0.59, p < 0.001). CONCLUSION: Delayed post space preparation seems to negatively influence apical sealing; however, further studies are needed to determine the influence of the timing of post space preparation on the other parameters. CLINICAL RELEVANCE: Immediate post space preparation may be the safest clinical choice to prevent apical leakage.

Mineral trioxide aggregate (MTA) inhibits osteoclastogenesis and osteoclast activation through calcium and aluminum activities.

OBJECTIVE: To evaluate the effect(s) of mineral trioxide aggregate (MTA) on in vitro RANKL-mediated osteoclast-dependent bone resorption events and the influence of Ca2+ and Al3+ on the osteoclastogenesis inhibition by MTA. MATERIALS AND METHODS: Two types of osteoclast precursors, RAW 264.7 (RAW) cell line or bone marrow cells (obtained from BALB/c mice and stimulated with recombinant (r) macrophage colony stimulation factor (M-CSF), were stimulated with or without recombinant (r) activator of nuclear kappa B ligand (RANKL), in the presence or absence of MTA for 6 to 8 days. White Angelus MTA and Bios MTA (Angelus, Londrina, Paraná, Brazil) were prepared and inserted into capillary tubes (direct contact surface = 0.50 mm2 and 0.01 mm2). Influence of MTA on these types of osteoclast precursors was measured by the number of differentiated tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (RAW and bone marrow cells), TRAP enzyme activity (RAW cells), cathepsin K gene expression (RAW cells), and resorptive pit formation (RAW cells) by mature osteoclasts. Besides, RAW cells were also stimulated with Ca2+ and Al3+ to evaluate the influence of these ions on MTA anti-osteoclastogenic potential. RESULTS: In bone marrow and RAW cells, the number of TRAP-positive mature osteoclast cells induced by rRANKL was significantly inhibited by the presence of MTA compared with control rRANKL stimulation without MTA (p < 0.05), along with the reduction of TRAP enzyme activity (p < 0.05) and the low expression of cathepsin K gene (p < 0.05). In contrast, to control mature osteoclasts, the resorption area on dentin was significantly decreased for mature osteoclasts incubated with MTA (p < 0.05). rRANKL-stimulated RAW cells treated with Ca2+ and Al3+ decreased the number of osteoclasts cells. Besides, the aluminum oxide was the dominant suppressor of the osteoclastogenesis process. CONCLUSIONS: MTA significantly suppressed RANKL-mediated osteoclastogenesis and osteoclast activity and, therefore, appears able to suppress bone resorption events in periapical lesions. This process might be related to Ca2+ and Al3+ activities. CLINICAL RELEVANCE: MTA is an important worldwidely acknowleged biomaterial. The knowledge about its molecular activities on osteoclasts might contribute to improving the understanding of its clinical efficacy.

3D Apicoectomy Guidance: Optimizing Access for Apicoectomies.

When conventional endodontic treatment resources are depleted, endodontic surgery becomes an alternative treatment for apical periodontitis to remove unreachable infected areas and seal the root canal. Digital workflows have been used more frequently in many dental applications in recent years. In endodontics, virtual 3-dimensional (3D) planning and endodontic guidance are new aspects important for the treatment of complex cases. This report aimed to present 3D Apicoectomy Guidance, a novel method of performing guided ultraconservative endodontic surgery with conventional implant-guided drills, and to describe its application in a case with a complex anatomic scenario and intimate contact with the maxillary sinus. Implantology computer software, as well as cone-beam computed tomography images and a digital scanning 3D impression, enabled virtual planning of the surgical procedure. Subsequently, a 3D template was produced to guide the instruments used in the osteotomy and root resection. The patient was completely asymptomatic at the 1-week follow-up visit. Cone-beam computed tomography scans were performed at 1 and 6 months after surgery and showed that resection of the apex of the root was performed accurately and that a thin dentin slice remained distally, preventing the rupture of the sinus membrane. The patient remained asymptomatic, and the tissue healed normally. The method used was shown to be very straightforward and reliable. This method allowed the patient to be treated expeditiously with very precise tissue removal.

The Influence of Bioceramic Cements on the Activity of Macrophages of Different Lineages: A Laboratory Study.

INTRODUCTION: The repair process of periradicular tissues depends, among other factors, on the properties of endodontic cements. Macrophages are among the main cells involved in this process. MATERIALS AND METHODS: Murine peritoneal macrophages obtained from C57BL/6 (MBL6) and BALB/c (MBalb) mice, respectively, were cultured with capillaries containing or not Endosequence BC Sealer (BC), Sealer Plus BC (MK), Bio-C Sealer (Ang), and mineral trioxide aggregate (MTA). Cell viability was measured by Trypan blue and MTT methods at 24, 48, and 72 hours. Cell adhesion, phagocytosis of Saccharomyces boulardii, production of reactive oxygen species (ROS), nitric oxide (NO), and the cytokines tumor necrosis factor-α and transforming growth factor (TGF)-ß were also evaluated. The data were analyzed using the analysis of variance test (P < .05). RESULTS: Cell viability was similar between bioceramic sealers and MTA (P > .05). There was no statistical difference between both macrophages when adherence and phagocytose were assayed. The presence of inflammation stimulus significantly altered the production of ROS by MBL6 macrophages in contact with the cements. The production of TGF-ß was similar for both lineages of macrophages. CONCLUSIONS: This study shows that the evaluated bioceramic cements do not interfere with MBL6 and MBalb macrophage adhesion, phagocytic capacity, or TGF-ß production. The cements stimulated the production of ROS by MBL6 macrophages in response to induced inflammation, potentially favoring the elimination of residual pathogens.

Surgical management of invasive cervical resorption using resin-modified glass ionomer cement.

Invasive cervical resorption is an external resorption that begins below the epithelial attachment. It is caused primarily by dental trauma, orthodontic treatment, or dental bleaching. This case report involved an invasive Class III cervical resorption resulting from trauma to the superior right central incisor. Root canal treatment was followed by surgical intervention. The resorptive defect was debrided, and part of the tooth was restored with resin-modified glass ionomer cement. Postoperative follow-up revealed complete healing and healthy gingival attachment.

Prevalence of traumatic dental injuries in emergency dental services: A systematic review and meta-analysis.

OBJECTIVES: This study aimed to perform a systematic review and meta-analysis regarding the prevalence of traumatic dental injuries (TDI) in emergency dental services. METHODS: Seven electronic and two grey literature databases were searched, up to December 2021, for studies that reported the TDI prevalence among dental emergencies. The Joanna Briggs Institute critical appraisal checklist for prevalence studies, and The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach were used to assess the risk of bias and quality of evidence respectively. The R software was used to perform a proportion meta-analysis on a random-effects model to estimate the pooled prevalence and respective 95% CI. RESULTS: From a total of 1476 studies identified after excluding duplicates, 38 met the inclusion criteria, and another five were identified through hand searching, summing 43 included observational studies with a total sample of 209099 individuals searching for emergency dental care. The overall pooled prevalence of TDI was 15.4% (95% CI: 11%-21%, I² = 100%). Paediatric dental emergency services and age group from 0 to 21 years presented the highest prevalence, 29% (95% CI: 22%-38%, I² = 99.5%) and 24% (95% CI: 15%-35%, I² = 98%) respectively. CONCLUSIONS: The overall pooled prevalence of TDI in emergency dental services was 15.4%, and 24% in the age group under 21 years. Considering the impact of prompt and correct emergency care in the long-term prognosis of TDI, such knowledge is relevant to organize emergency healthcare and support public policies in this area.

National analysis of dental teleconsulting of the Brazilian Telehealth Program.

This cross-sectional study nationally evaluated asynchronous dental teleconsulting services offered by the Telehealth Brazil Networks Program, using the 2019 Telehealth Results Monitoring and Evaluation System database and considering Brazilian regional differences. The following teleconsulting variables were collected: dentist's sex and specialty, date/time of question and answer, response time; dental specialty, professional satisfaction, and patient referral. Five Brazilian regions were socioeconomically characterized according to the Human Development Index, estimated population, Gini coefficient, coverage of dental specialty centers, oral health teams in Family Health Strategy, and oral health teams in primary health care (PHC). In total, 2,703 teleconsulting sessions occurred in Brazil in the analyzed period. The Southeast exhibited the highest demand (49.1%). Most dentists were female (60.6%) and were dental surgeons from the Family Health Strategy (61.3%). Most teleconsulting sessions occurred during working hours (85.5%) and questions were answered within 72 hours (66.7%). Level of satisfaction and avoidance of referral yielded rates of 90.9% and 66.8%, respectively, among dentists who answered about these topics. Semiology was the most frequently demanded area in teleconsulting (33.9%). The different demands from the regions reflected regional differences. The most frequently demanded specialties represent the Brazilian PHC scenario. Professionals incorporated teleconsulting into their work routine and most teleconsultants responded within the stipulated timeframe. Professional feedback should be encouraged.

Limitations and Management of Static-guided Endodontics Failure.

Endodontic treatment in severely calcified canals is always a challenging task because it can result in accidents such as deviations or perforations. Recently, guided endodontics has become an alternative approach for pulp canal calcification, facilitating the location of root canals more predictably through the combined use of cone-beam computed tomographic imaging, oral scanning, and endodontic access guides. Although several reports have shown that guided endodontics is safer, faster and can be performed without an operating microscope and by less experienced operators, the technique has limitations, and iatrogenesis may occur. This article describes the limitations of static-guided endodontics and possible causes of failures. In the present case, not fixing the guide to the bone and inaccuracies generated by manually performing mesh merger software led to root perforation. Endodontic microsurgery was effective in resolving this case and should be considered the treatment of choice when guided endodontics cannot be used safely or when it fails.

Guided Endodontic Approach in Teeth with Pulp Canal Obliteration and Previous Iatrogenic Deviation: A Case Series.

Pulp canal obliteration (PCO) is a challenging clinical scenario in which canals must be located in progressively narrowing roots. Recently, proof of concept papers have, in parallel, introduced the combination of cone-beam computed tomography and surface scans for the construction of guides to pilot the negotiation and preparation of partially or completely obliterated pulp chambers and canals in anterior and posterior teeth. Authors' purpose is to describe the treatment approach for teeth with PCO and previous iatrogenic deviation using guided endodontic technique. The clinical cases reported here show that technological evolutions should make guided endodontic procedures more widespread because their execution is relatively fast and safe even in the cases of root canal deviation. Treatment of teeth with pulp canal obliteration with deviations or perforation may be more effective with designed 3D printed access guides that seems to be a safe and clinically feasible method to locate root canals.

The response of Mesenchymal Stem Cells to endodontic materials.

An endodontic material must be minimally harmful to stem cells since they are essential, thanks to their capacity for cell proliferation, self-renewal, and differentiation. For this reason, in this in vitro study, the cell viability and the expression of genes involved in cell plasticity and differentiation were investigated in stem cells recovered from human dental pulp (hDPSCs) that were in contact with four endodontic materials (Endofill, MTA, Pulp Canal Sealer, and Sealer 26). The viability of HDPSCs was assessed by MTT and trypan blue exclusion assays. PCR evaluated cellular plasticity by determining the CD34, CD45, Nestin, CD105, Nanog, and OCT4 expressions. The effect on cell differentiation was determined by RT-PCR expression of the RUNX2, ALP, OC/BGLAP, and DMP1 genes. The data were analyzed using ANOVA with Bonferroni correction (p <0.05). Pulp Canal Sealer and Endofill decreased cell viability after 48 hours (p <0.001). MTA and Sealer 26 did not disrupt cell viability (p> 0.05). When cultivated in the presence of MTA and Sealer 26, hDPSCs expressed Nestin, CD105, NANOG, and OCT-4 and did not express CD34 and CD45. MTA and Sealer 26 interfered with DMP1, OC/BGLAP and RUNX2 expressions (p <0.05) but did not change ALP gene expression (p> 0.05). MTA and Sealer 26 showed biological compatibility in the presence of hDPSCs.

Synergistic growth effect among bacteria recovered from root canal infections.

The objective of this study was to determine the ecological relationships between bacterial species that colonize infected root canals. Root canal bacteria recovered from one patient with pulp canal necrosis were evaluated in vitro for synergistic and antagonistic activities determined by mono and co-culture growth kinetics and the production of bacteriocin-like substances using the double layer diffusion method. Peptostreptococcus prevotii triggered a significant increase of Fusobacterium nucleatum growth, while the former bacteria did not affect the growth of P. prevotii. The bacterial species did not produce antagonism activity against itself or against any of the other two species. Despite many studies have demonstrated the capability of root canal microorganisms to produce antagonistic substances, these in vitro experimental tests show the synergistic effect of P. prevotii on the growth of F. nucleatum.

Combined Endodontic and Surgical Therapy for Resolution of Type III Dens Invaginatus.

Dens invaginatus is an abnormal dental developmental, probably resulting of the invagination of mineralized tissues from the tooth crown surface before its calcification. The teeth that are most affected by this abnormality are the maxillary lateral incisors. This dental developmental anomaly has various types and the rarest is type III which has the worst prognosis, because of its complex anatomy. Conventional root canal therapy may not sufficiently resolve the case itself and in some circumstances the surgical intervention is also necessary. This report addresses a complex combined endodontic treatment of a type III dens invaginatus in a maxillary lateral incisor in an 18 years-old female patient, with an extensive periapical lesion affecting the buccal and palatine cortical bone, diagnosed by cone-beam computed tomography (CBCT). The case was conducted with the combination of endodontic and surgical treatment, under the use of the surgical operating microscope. The association of CBCT, visual magnification, XP-endo Finisher, bioceramic sealer, MTA Repair HP and bone graft were important to ensure predictable success.

The apical root canal system microbial communities determined by next-generation sequencing.

The aim of this study was to explore the microbial communities of endodontic infections at their apical portion by 16S rRNA Illumina sequencing and delineate the core microbiome of root canal infections and that of their associated clinical symptomatology. Samples were collected from fifteen subjects presenting one tooth with a root canal infection, and their associated symptoms were recorded. Samples were collected from the apical third of roots using a #10 K file and then amplified using multiple displacement amplification and PCR-amplified with universal primers. Amplicons were sequenced (V3-V4 hypervariable region of the 16S rRNA gene) using MiSeq (Illumina, CA). The microbial composition of the samples was determined using QIIME and HOMINGS. Data were analyzed using t tests and ANOVA. A total of 1,038,656 good quality sequences were obtained, and OTUs were assigned to 10 bacterial phyla, led by Bacteroidetes (51.2%) and Firmicutes (27.1%), and 94 genera were represented primarily by Prevotella (17.9%) and Bacteroidaceae G-1 (14.3%). Symptomatic teeth were associated with higher levels of Porphyromonas (p < 0.05) and Prevotella. P. endodontalis and P. oris were present in both cores. The present study demonstrated the complexity of the root canal microbiome and the "common denominators" of root canal infections and identified taxa whose virulence properties should be further explored. The polymicrobial etiology of endodontic infections has long been established. However, few studies have focused on expanding the breadth and depth of coverage of microbiome-infected root canals at their apical portion.

Oral Medicine and Pharmacology Teleconsulting Sessions of the Telehealth Program in one Southeastern State of Brazil

ABSTRACT Objective: To evaluate questions concerning oral medicineand pharmacology-related specialties of asynchronous dental teleconsulting sessions of the Telehealth Brazil Networks Program. Material and Methods: Data were collected from secondary databases of asynchronous dental teleconsulting sessions of the telehealth centers of Minas Gerais from July 2015 to July 2017. The variables for dental underlying fields and the types of questions were evaluated. Descriptive analysis was performed with the SPSS v.22.0 program. Results: 3,920 teleconsulting sessions were referred to the telehealth centers of Minas Gerais during the study period. Regarding oral medicine-related questions (n=745), most (n=469; 62.95%) addressed diagnosis, whereas the underlying field questions mostly regarded fungal, viral, and bacterial infections (17.3%), biopsies (16.4%), developmental defects and dental abnormalities (9.9%), and soft tissue tumors (9.4%). Pharmacology-related questions (n=738) mostly addressed general approaches (n=672; 91.06%), and the most common questions were about underlying fields' prescriptions (44.7%), anesthetics (17.6%), adverse effects of medications and anesthetics (10.2%), and selection of anesthetics for patients with systemic conditions (9.8%). Conclusion: Most teleconsulting sessions regarded conditions or procedures common in primary health care and essential for diagnosis and treatment planning at all care levels, which suggests a need for more academic learning processes for healthcare professionals, especially in dentistry primary fields.

Influence of genetic regulatory effects modified by environmental immune activation on periapical disease.

The objective of this study was to compare the periradicular responses in endodontic infections among members of two populations: an urban Brazilian population and a non-mixed indigenous population. Samples were collected immediately and 7 days after the cleaning and shaping procedures (after reducing the intracanal microbial load) in an attempt to characterize the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-9, interferon (IFN)-γ, IL-17, IL-10, and the chemokines CXCR4, CCL2/monocyte chemotactic protein (MCP)-1, and CCR6. The endogenous cytokine and chemokine expression levels were analyzed using real-time PCR. Only the urban population showed a significant increase in TNF-α, CCL2/MCP-1, CXCR4, and CCR6 expression following the cleaning and shaping of the root canal system. The IFN-γ levels were increased at the 2nd collection (p < 0.05) in the indigenous population. In turn, a significant increase in IL-10 and IL-17 expression (p < 0.05) was observed after the cleaning and shaping procedures (2nd collection) in both populations. No significant differences in the IL-1ß, IL-9, and CCL4 expression levels were observed between the 1st and 2nd collections in both populations. The results demonstrate a cytokine and chemokine expression profile that is specific to each analyzed population. However, immune modulation mediated by IL-10 began on the 7th day after the beginning of the endodontic treatment in both populations.

Case Reports in Maxillary Posterior Teeth by Guided Endodontic Access.

The localization of partial or completed root canal obliteration is a challenging task in endodontic practice. Recently, guided endodontics has become an alternative solution for those cases. Although this technique has already been used clinically in managing anterior teeth, in this report, we describe 3 complex clinical scenarios of calcified root canals of 1 molar and 2 premolars using guided endodontics. The clinical cases reported here show that technological evolutions should make guided endodontic procedures more widespread because their execution is relatively fast and safe even in the case of the upper molar. Additionally, 12-month clinical follow-up visits showed the effectiveness of the guided endodontic procedures.

Scanning Electron Microscopic/Energy-Dispersive X-Ray Analysis in Cases of Apical Periodontitis Refractory to Endodontic Treatment: A Case Series Study.

This study aimed to present a case series of refractory endodontic treatment leading to persistent apical periodontitis. All cases were submitted to scanning electron microscopic/energy-dispersive X-ray analysis (SEM/EDS) of the external surface of the surgically removed samples and identification of the elements present in the specimens. Carbon, oxygen and calcium were elements present in all of the cases in this study. The presence of microorganisms in close contact with the periapical surrounding tissues induced the perpetuation of the inflammation process. Despite the presence of other elements different from those normally expected in the tissues, we may not attribute any interference in the periapical response to them.

Evaluation of chemokines and receptors in gnotobiotic root canal infection by F. nucleatum and E. faecalis.

The present study aims to evaluate the longitudinal effects of induced experimental infections in gnotoxenic animals on the expression of inflammatory chemokines and their receptors in periradicular tissues. The null hypothesis tested was that Enterococcus faecalis and Fusobacterium nucleatum had no effect on CCR5, CCL5, CXCL10, CCL2/MCP-1, CXCR2 and CCR1 expression. Two groups of five animals (n = 5) aged between 8 and 12 weeks were used in this study. The animals were anaesthetized, and coronary access was performed in the first molar on the right and left sides. Microorganisms were inoculated into the left molar, and the right molar was sealed without contamination to function as a control. Animals were sacrificed 7 and 14 days after infection, and periapical tissues were collected. The cytokine mRNA expression levels were assessed using real-time PCR. The chemokine mRNA expression levels demonstrated that the experimental infection was capable of inducing increased chemokine expression on day 7 compared to that on day 14, except for CCR5 and CCL5, which showed no changes. The gnotoxenic animal model proved to be effective and allowed evaluation of the immune response against a known infection. Additionally, this study demonstrates that gene expression of chemokines and their receptors against the experimental infection preferentially prevailed during the initial phase of induction of the periradicular alteration (i.e., on day 7 post-infection).