Effectiveness of pulpotomy compared with root canal treatment in managing non-traumatic pulpitis associated with spontaneous pain: A systematic review and meta-analysis.

BACKGROUND: Pulpitis characterized by spontaneous pain can result in debilitating pain. Dogma has existed to offer only have two treatment options, namely root canal treatment (RCT) or extraction, although pulpotomy has always remained a potential treatment modality. OBJECTIVE: This review aimed to answer the following research question: 'Does pulpotomy (partial or full) (I) result in better patient and clinical reported outcomes (O), compared with RCT (C) in permanent teeth with pulpitis characterized by spontaneous pain (P) evaluated at various time intervals?' (T). METHODS: Two authors independently performed study selection, data extraction and risk of bias assessment. The literature search was conducted in the following electronic databases: Clarivate Analytics' Web of Science, Scopus, PubMed and Cochrane Central Register of Controlled Trials. English language clinical trials comparing the patient and clinical reported outcomes between RCT and pulpotomy were included. The meta-analysis was performed on a fixed-effect model and the quality of evidence assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. RESULTS: Two randomized clinical trials were included. Amongst two trials, one has published four reports at different time points involving the same cohorts. The meta-analysis revealed no difference in postoperative pain (Day 7) between RCT and pulpotomy (OR = 0.99, 95% CI 0.63-1.55, I2  = 0%) and quality of evidence was graded as 'High'. Clinical success was high at year 1, 98% for both interventions, however, decreased over time to 78.1% (pulpotomy) and 75.3% (RCT) at 5 years. DISCUSSION: Pulpotomy is a definitive treatment modality that is as effective as RCT. This could have a significant impact on treatment of such patients affording the advantages of retaining a vital pulp and preventing the need for RCT. CONCLUSION: This review could only include two trials, hence there is insufficient evidence to draw robust conclusions. The clinical data accumulated so far suggests no difference in pain between RCT and pulpotomy at Day 7 postoperatively and a single randomized control trial suggests that the clinical success rate for both treatment modalities is similar long term. There is a need for more well-designed trials by different research groups to develop a stronger evidence base in this area. REGISTRATION: PROSPERO database (CRD42021259744).

Periradicular tissue fluid-derived biomarkers for apical periodontitis: An in vitro methodological and in vivo cross-sectional study.

BACKGROUND: Periradicular tissue fluid (PTF) offers a source of diagnostic, prognostic and predictive biomarkers for endodontic disease. AIMS: (1) To optimize basic parameters for PTF paper point sampling in vitro for subsequent in vivo application. (2) To compare proteomes of PTF from teeth with normal apical tissues (NAT) and asymptomatic apical periodontitis (AAP) using high-throughput panels. METHODOLOGY: (1) To assess volume absorbance, paper points (n = 20) of multiple brands, sizes and sampling durations were inserted into PBS/1%BSA at several depths. Wetted lengths (mm) were measured against standard curves to determine volume absorbance (µL). To assess analyte recovery, paper points (n = 6) loaded with 2 µL recombinant IL-1ß (15.6 ng/mL) were eluted into 250 µL: (i) PBS; (ii) PBS/1% BSA; (iii) PBS/0.1% Tween20; (iv) PBS/0.25 M NaCl. These then underwent: (i) vortexing; (ii) vortexing/centrifugation; (iii) centrifugation; (iv) incubation/vortexing/centrifugation. Sandwich-ELISAs determined analyte recovery (%) against positive controls. (2) Using optimized protocols, PTF was retrieved from permanent teeth with NAT or AAP after accessing root canals. Samples, normalized to total fluid volume (TFV), were analysed to determine proteomic profiles (pg/TFV) of NAT and AAP via O-link Target-48 panel. Correlations between AAP and diagnostic accuracy were explored using principal-component analysis (PCA) and area under receive-operating-characteristic curves (AUC [95% CI]), respectively. Statistical comparisons were made using Mann-Whitney U, anova and post hoc Bonferonni tests (α < .01). RESULTS: (1) UnoDent's 'Classic' points facilitated maximum volume absorbance (p < .05), with no significant differences after 60 s (1.6 µL [1.30-1.73]), 1 mm depth and up to 40/0.02 (2.2 µL [1.98-2.20]). For elution, vortexing (89.3%) and PBS/1% BSA (86.9%) yielded the largest IL-1ß recovery (p < .05). (2) 41 (NAT: 13; AAP: 31) PTF samples proceeded to analysis. The panel detected 18 analytes (CCL-2, -3, -4; CSF-1; CXCL-8, -9; HGF; IL-1ß, -6, -17A, -18; MMP-1, -12; OLR-1; OSM; TNFSF-10, -12; VEGF-A) in ≥75% of AAP samples at statistically higher concentrations (p < .01). CXCL-8, IL-1ß, OLR-1, OSM and TNFSF-12 were strongly correlated to AAP. 'Excellent' diagnostic performance was observed for TNFSF-12 (AUC: 0.94 [95% CI: 0.86-1.00]) and the PCA-derived cluster (AUC: 0.96 [95% CI: 0.89-1.00]). CONCLUSIONS: Optimized PTF sampling parameters were identified in this study. When applied clinically, high-throughput proteomic analyses revealed complex interconnected networks of potential biomarkers. TNFSF-12 discriminated periradicular disease from health the greatest; however, clustering analytes further improved diagnostic accuracy. Additional independent investigations are required to validate these findings.

Anti-inflammatory and anti-resorptive efficacy of adrenergic blockers on late replanted rat incisors.

BACKGROUND/AIM: In addition to their anti-inflammatory and anti-osteoclastogenesis properties, adrenergic blockers may also have promising anti-resorptive effects that can prevent root resorption when teeth are replanted because of avulsion. The aim of this study was to investigate the effects of phentolamine (Ph) and propranolol (Pr) in gels on the repair process of late replanted rat incisors. A further aim was to evaluate the biocompatibility of both drugs to human periodontal ligament fibroblasts (HPDLFs). MATERIALS AND METHODS: Forty-eight maxillary right incisors were extracted from male Wistar rats, stored in paper napkins for 60 minutes, and randomly allocated to one of eight groups (n = 6). The root canal, root surface, and alveolus were treated with 0.75 µg/mL Ph gel (Ph0.75), 10 µg/mL Ph gel (Ph10), 100 µg/mL Ph gel (Ph100), 2.5 µg/mL Pr gel (Pr2.5), 10 µg/mL Pr gel (Pr10), 100 µg/mL Pr gel (Pr100), or sodium carboxymethylcellulose gel (CMC) before replantation. In the control group (CH), only the root canal was treated with calcium hydroxide paste. Thirty days following surgery, the animals were euthanized, and the right hemimaxilla was removed to perform micro-CT and histomorphometric analysis to determine osteoclastic activity. Ethanolic solutions of Ph10 and Pr10 were selected based on the in vivo study, and the viability of HPDLFs stimulated with lipopolysaccharide was determined by MTT assays. RESULTS: The micro-CT and histomorphometric analysis revealed no significant differences among the treatments (P > .05). The presence of active osteoclasts was significantly decreased in the Ph10 and Pr10 groups (P < .05). Ph10 and Pr10 produced statistically similar cell survival rates compared to the control group (P > .05). CONCLUSIONS: Ph10 and Pr10 significantly decreased osteoclastogenesis in delayed replanted rat teeth and were not cytotoxic toward HPDLFs.

Atraumatic surgical extrusion to improve tooth restorability: A clinical report.

This clinical report describes the use of an "atraumatic" vertical extraction system to facilitate the restorative treatment of a tooth that would otherwise be considered unrestorable because of subgingival caries. Minimally invasive surgical root extrusion was undertaken using the Benex extraction system, which can provide controlled tooth extrusion with minimal deformation of the bone socket. A carious endodontically treated mandibular premolar was extruded to provide routine restorative treatment and endodontic retreatment.

Hepatocyte growth factor is sequestered in dentine matrix and promotes regeneration-associated events in dental pulp cells.

Extracellular matrix of dentine contains a rich cocktail of soluble cytokines and growth factors which mediate wound repair of the dentine-pulp complex. Hepatocyte growth factor (HGF) is a mesenchyme derived growth factor regulating a broad range of physiological processes including tissue development and regeneration. In this study, we have investigated the sequestration of HGF in the dentine matrix and analysed its action as a chemokine in the induction of differentiation and mineral deposition in pulp derived cells in vitro. Using ELISA, the presence of HGF was demonstrated in solubilised fractions of dentine matrix released by the therapeutic pulp repair materials of white and grey mineral trioxide aggregate. HGF was shown to be a chemo-attractant for primary rat dental pulp cells (RDPCs) in transwell assays highlighting its potential in progenitor cell recruitment during dentine-pulp tissue repair. Transcription factors Osterix and Runx2, and genes encoding for Osteopontin and Osteocalcin, were up-regulated in HGF-exposed RDPC cultures compared with controls. Adenoviral-mediated expression of HGF in RDPCs or exposure to recombinant HGF induced mineral secretion in RDPCs which was significantly greater than controls. The receptor of HGF, c-Met was also detected within human dental pulp indicating the potential for HGF released from dentine matrix to contribute to cellular signalling events following tissue injury. Combined, these data suggest that HGF is important in the repair of the dentine-pulp complex potentially participating in several aspects of wound healing.

The Impact of the Preferred Reporting Items for Case Reports in Endodontics (PRICE) 2020 Guidelines on the Reporting of Endodontic Case Reports.

Aim The aim of this study is to evaluate the impact of the Preferred Reporting Items for Case reports in Endodontics (PRICE) 2020 guideline on the reporting of published endodontic case reports (CRs). Methodology All case reports published in the International Endodontic Journal, European Endodontic Journal, Journal of Endodontics and Restorative Dentistry and Endodontics, in the year before and after the release of PRICE 2020, were included for analysis. Two panels comprising dentists scored case reports against a scoring system adapted from the guideline. Individual items were scored up to a maximum of 1; scores were then summated to provide an overall maximum of 47 for each CR. Each report provided an overall percentage adherence, and panel agreement was calculated using the intraclass correlation coefficient (ICC). Disagreement on scoring was discussed until a consensus was reached. Scores before and after PRICE guideline publication were compared using an unpaired two-tailed t test. Results A total 19 CRs were identified in both the pre- and post-PRICE guideline publication. Mean adherence to PRICE 2020 increased by 7.9% (p=0.003) from 70.0%±8.89 to 77.9%±6.23 following its publication. Agreement between panels was moderate (ICC pre-PRICE: 0.673 {p=0.011}; ICC post-PRICE: 0.742 {p=0.003}). Items 1a, 6c, 6e, 6f, 6g, 6j, 6q, 6s, 7a, 9a, 11a, 12c and 12d experienced a fall in compliance. Conclusion The PRICE 2020 guideline has resulted in a modest improvement in the reporting of endodontic case reports. Greater awareness and a wider acceptance and implementation of the guideline in endodontic journals are needed to improve adherence to the novel guideline.

Exploiting Dentine Matrix Proteins in Cell-Free Approaches for Periradicular Tissue Engineering.

The recent discovery of mesenchymal stem cells within periapical lesions (PL-MSC) has presented novel opportunities for managing periradicular diseases in adult teeth by way of enhancing tissue regeneration. This discovery coincides with the current paradigm shift toward biologically driven treatment strategies in endodontics, which have typically been reserved for non-vital immature permanent teeth. One such approach that shows promise is utilizing local endogenous non-collagenous dentine extracellular matrix components (dECM) to recruit and upregulate the intrinsic regenerative capacity of PL-MSCs in situ. At picogram levels, these morphogens have demonstrated tremendous ability to enhance the cellular activities in in vitro and in vivo animal studies that would otherwise be necessary for periradicular regeneration. Briefly, these include proliferation, viability, migration, differentiation, and mineralization. Therefore, topical application of dECMs during ortho- or retrograde root canal treatment could potentially enhance and sustain the regenerative mechanisms within diseased periapical tissues that are responsible for attaining favorable clinical and radiographic outcomes. This would provide many advantages when compared with conventional antimicrobial-only therapies for apical periodontitis (AP), which do not directly stimulate healing and have had stagnant success rates over the past five decades despite significant advances in operative techniques. The aim of this narrative review was to present the novel concept of exploiting endogenous dECMs as clinical tools for treating AP in mature permanent teeth. A large scope of literature was summarized to discuss the issues associated with conventional treatment modalities; current knowledge surrounding PL-MSCs; composition of the dECM; inductive potentials of dECM morphogens in other odontogenic stem cell niches; how treatment protocols can be adapted to take advantage of dECMs and PL-MSCs; and finally, the challenges currently impeding successful clinical translation alongside directions for future research. Impact statement Apical periodontitis (AP) is an inflammatory condition that is associated with a great degree of morbidity and ultimately leads to tooth loss. The purpose of this review was to summarize the current evidence pertaining to stem cell therapy in endodontics and present a novel clinical methodology through which they may be utilized to address AP. A comprehensive overview of the basic science, clinical translation, and potential challenges are presented in this review.

Preserving pulp vitality: part two - vital pulp therapies.

Vital pulp therapies (VPTs) aim to preserve the vitality of the pulp. The European Society of Endodontology have begun a campaign to raise awareness on the efficacy of VPTs following on from the publication of their 2019 position statement, aimed at both specialists and general dental practitioners. This review examines the current evidence surrounding VPTs and provides a rational approach to the management of the exposed pulp with the aid of case studies. Success lies in accurate diagnosis and case selection, along with well-executed treatment and appropriate follow-up protocols. The introduction of calcium silicate cements has made these treatments more predictable.

Preserving pulp vitality: part one - strategies for managing deep caries in permanent teeth.

This is the first article in a series reviewing the current literature surrounding the management of deep caries in permanent teeth. Approaches to caries management are continuing to evolve, with more conservative management increasingly favoured. This philosophy has never been more important than in managing the deep carious lesion. Evidence is emerging that the use of selective caries removal to reduce the risk of pulp exposure, in conjunction with calcium silicate cements, can be successful in maintaining pulp vitality, delaying the restorative cycle and prolonging the lifespan of the tooth.

A matched irrigation and obturation strategy for root canal therapy.

In root canal therapy, irrigating solutions are employed to eliminate the bacterial load and also prepare dentin for sealer interaction. The aim of this research was to assess how irrigating solutions employed on their own or in sequence affected the tooth structure. The best way to prepare the tooth for obturation using hydraulic calcium silicate cement (HCSC) sealers and gutta-percha, thus guiding clinicians on a matched irrigation-obturation strategy for optimized root canal treatment was investigated. The effect of irrigating solutions on dentine was investigated by assessing changes in dentin microhardness, ultrastructure and mineral content, organic/inorganic matter, surface roughness and Young's modulus. The interaction of four root canal sealers with the dentin was analysed by assessing the changes in microhardness of the dentin after sealer placement and also the sealer to dentin interface by scanning electron and confocal laser microscopy. The irrigating solutions damaged the dentin irreversibly both when used on their own and in combination. The best sequence involved sodium hypochlorite followed by chelator and a final rinse with sodium hypochlorite and obturation using HCSC sealers that enabled the restoration of dentin properties. The HCSC sealers did not rely on chelator irrigating solutions for a good material adaptation to dentin.

Current trends in endodontic irrigation amongst general dental practitioners and dental schools within the United Kingdom and Ireland: a cross-sectional survey.

Aims To investigate current trends in endodontic irrigation amongst general dental practitioners (GDPs) and dental schools within UK and Ireland. Secondly, to evaluate if significant differences exist between the irrigant practices of National Health Service (NHS) and private GDPs.Methodology In 2019, an online questionnaire was distributed to the 18 dental schools within the UK and Ireland and 8,568 GDPs. These surveys explored current trends in teaching and usage of endodontic irrigants. Chi-squared tests were performed to make comparisons between NHS and private GDPs (α <0.01).Results All 18 dental schools (100%) and 495 GDPs (6%) returned valid questionnaires. Three hundred and thirty (66.7%) practitioners were NHS and 165 (33.3%) were private. There was strong consensus on irrigation teaching amongst dental schools. These results aligned with GDP responses in terms of irrigant selection (sodium hypochlorite [NaOCl]); NaOCl concentration (≤3%); ethylenediaminetetraacetic acid (EDTA) contact time (>0-5 minutes); final rinse protocols (penultimate EDTA rinse); irrigant temperature (room); and agitation techniques (manual dynamic activation; >0-60 seconds). There was, however, considerable variation in NaOCl contact time and GDPs infrequently used chelating agents or agitation techniques. Compared with private practitioners, NHS GDPs used significantly lower NaOCl contact times and concentrations, less EDTA and activation techniques, and more chlorhexidine (P <0.01).Conclusions Overall, irrigation teaching within the UK and Ireland is consistent and evidence-based. Furthermore, trends in irrigant usage amongst UK GDPs are now more aligned with these teaching practices. Significant differences were, however, observed between NHS and private practitioners.

Apical limit and working length in endodontics.

UNLABELLED: Establishing the working length is an important step in endodontic treatment as inaccurate length determination may lead to failure. There is an ongoing debate regarding the extent of the apical limit of root canal preparation. This controversy is based upon different clinical opinions concerning the distance between the end point of the root canal preparation and the periodontal tissues. In this paper, we review the different schools of thought for working length determination, and how apex locators work and how they must be used for optimal accuracy. The reliability of these devices has been proven; the price is moderate and apex locators are now part of the basic armamentarium in the achievement of quality and predictable endodontic treatment. CLINICAL RELEVANCE: The technique of determining the working length from a single radiograph remains empirical, and apex locators should be considered an essential aid in establishing working length.

Expression of Neurotrophic Factors in Human Dentin and Their Regulation of Trigeminal Neurite Outgrowth.

INTRODUCTION: Neurotrophic factors play a significant role in the innervation of the pulp-dentin complex during and after organogenesis. There have been numerous bioactive molecules identified in the dentin extracellular matrix; however, the expression of neurotrophic factors in the dentin matrix and their biological activity are largely unknown. The purpose of this study was to characterize the relative expression of neurotrophic factors in human dentin matrix proteins (DMPs) and their effect on neurite outgrowth of trigeminal (TG) neurons. METHODS: Dentin was powdered in liquid nitrogen from noncarious human third molar teeth. DMPs were solubilized through an EDTA extraction method, dialyzed, and lyophilized until use. The relative expression of nerve growth factor, brain-derived neurotrophic factor, glial cell-line derived neurotrophic factor, neurotrophin 3, and neurotrophin 4/5 was determined by the enzyme-linked immunosorbent assay. Rat TG neurons were cultured and exposed to different concentrations of DMPs (1-105 ng/mL) or vehicle, and a quantitative neurite outgrowth assay was performed. RESULTS: Human DMPs contained all of the tested neurotrophic factors, with glial cell-line derived neurotrophic factor and neurotrophin 4/5 found at the highest levels. DMPs were able to promote the neurite outgrowth of rat TG neurons at an optimum concentration of 10-102 ng/mL, whereas the effect was partially inhibited at higher concentrations (>103 ng/mL). CONCLUSIONS: The human dentin extracellular matrix is a rich reservoir for neurotrophic factors that are key components for neuronal homeostasis, differentiation, and regeneration. These data suggest that neurotrophins in DMPs could play an important role as signaling molecules for the innervation of the pulp-dentin complex during the processes of tooth formation, repair, and regeneration.

Restoring the unrestorable! Developing coronal tooth tissue with a minimally invasive surgical extrusion technique.

Surgical extrusion is a recognised treatment option for teeth that have insufficient coronal tooth structure remaining due to deep caries, resorption or traumatic injury. However, the technique has not been widely adopted, arguably because extraction of a severely compromised tooth may be difficult to achieve in a gentle and predictable way. In this paper, we present our novel approach to surgical extrusion and subsequent management of teeth using a vertical extraction system (Benex), which has become the method of choice in the authors' practice for many teeth that would otherwise be deemed unrestorable. We describe the clinical procedure in detail and discuss the advantages and disadvantages compared to alternative approaches, including surgical crown lengthening and orthodontic extrusion.

Enhanced NHS endodontic services in England: a postcode lottery?

Aim To investigate the consistency of commissioning and provision of enhanced NHS endodontic services across England.Methods The level of provision for enhanced endodontic services was sought using two methods. An electronic questionnaire was distributed to each of the thirteen director of commissioning operations (DCO) teams in NHS England to determine the perception from commissioners of what endodontic services are currently provided and commissioned. A systematic search to assess what is advertised by enhanced endodontic providers was also carried out to cross-reference with the information gained from electronic questionnaires.Results A 77% response rate to the questionnaire was achieved. Eight out of the ten DCO teams that replied provided enhanced NHS endodontics to a greater or lesser extent, one did not and one was unsure. Three teams did not respond. Providers of services included dentists with enhanced skills, endodontic specialists, and dentists working within district or dental hospitals. Five out of ten DCO teams commissioned level two services and six commissioned level three services. Dental hospital acceptance criteria for enhanced endodontics differ regionally, but most accept level three and some level two complexity treatments, depending upon capacity at the time.Conclusions This investigation demonstrates that although the majority of NHS commissioning areas within England provide enhanced endodontic services, these are not the same across the country. Therefore, patients are not getting equal access to services and it may vary depending upon location.

The single cone obturation technique with a modified warm filler.

OBJECTIVES: The aim of this study was to develop a new method of obturation by warm sealer in conjunction to single cone gutta-percha and evaluate the suitability of this technique to obturate complex root canal systems. METHODOLOGY: Three root canal sealers namely, AH Plus, BioRoot RCS, GuttaFlow and a prototype sealer composed of tricalcium silicate and 30% zirconium oxide mixed with water and water-soluble polymer were investigated. The sealers were tested for flow, film thickness, setting time and radiopacity following ISO 6876 (2012) recommendations at room temperature and following heat application at 100°C to change the sealer properties. All the test sealers were characterized by scanning electron microscopy and energy dispersive spectroscopy. The volume of voids when used with a single cone obturation technique both unmodified and modified by heat was evaluated using microcomputed tomography. RESULTS: Although the prototype sealer was designed to be similar to the BioRoot, its physical properties were found to be different. All sealers tested were affected by the heat and exhibited a change in the physical properties mainly the setting time, flow, film thickness and void volume. CONCLUSIONS: The application of heat affected the sealer properties and void volume. The single cone obturation technique may not be suitable for complex canal anatomy and furthermore, AH Plus should not be subjected to high temperatures as its properties deteriorate and void volume increases.

Effect of Dentin Matrix Components on the Mineralization of Human Mesenchymal Stromal Cells.

IMPACT STATEMENT: This research has been conducted with the aim to contribute to the development of treatment modalities for the reconstruction of lost/damaged mineralized tissues. Currently, determining the most appropriate stromal cell population and signaling cues stands at the core of developing effective treatments. We provide new insights into the effect of innate inductive cues found in human dentin matrix components, on the osteogenic differentiation of various human stromal cell types. The effects of dentin extracellular matrix components on umbilical cord mesenchymal stromal cells have not been investigated before. The findings of this study could underpin translational research based on the development of techniques for mineralized tissue engineering and will be of great interest for the readership of Tissue Engineering Part A.

Pulpotomy for mature carious teeth with symptoms of irreversible pulpitis: A systematic review.

OBJECTIVES: Management of carious teeth with signs and symptoms indicative of irreversible pulpitis is traditionally invasive, but emerging evidence suggests successful treatment outcomes with less invasive vital pulp treatment such as coronal pulpotomy. The objective of this systematic review is to determine whether coronal pulpotomy is clinically effective in treating carious teeth with signs and symptoms indicative of irreversible pulpitis. SOURCES: MEDLINE; PubMed; Embase, Web of Science, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform and ClinicalTrials.gov were searched until December 2018. STUDY SELECTION: Prospective, retrospective and randomised clinical trials investigating coronal pulpotomy or comparing pulpotomy to root canal treatment in permanent mature carious teeth with signs and symptoms indicative of irreversible pulpitis were included. Studies were independently assessed for risk of bias using Cochrane Systematic Reviews of intervention criteria and modified Downs and Black quality assessment checklist. DATA: Eight articles were selected for analysis. The average success rate for coronal pulpotomy was 97.4% clinical and 95.4% radiographic at 12 month follow-up. This was reduced to 93.97% clinical and 88.39% radiographic success at 36 months follow-up. Results from the only comparative clinical trial showed pulpotomy to have comparable success to root canal treatment at 12, 24 and 60 month follow-up. CONCLUSIONS: The evidence suggests high success for pulpotomy for teeth with signs and symptoms of irreversible pulpitis, however, results are based on heterogeneous studies with high risk of bias. Well-designed, adequately powered randomised controlled trials are required for evidence to change clinical practice. CLINICAL SIGNIFICANCE: Management of carious teeth with irreversible pulpitis is traditionally invasive, but emerging evidence suggests potentially successful treatment outcomes with less invasive therapies such as coronal pulpotomy.

Influence of fractured instruments on the success rate of endodontic treatment.

UNLABELLED: The fracture of an instrument is a recognized complication in endodontics. The immediate response to a fractured instrument is frequently to regard the treatment as a failure. Several factors must, however, be taken into account to evaluate the prognosis of the tooth in this situation. The objective of the endodontic treatment with or without a fractured instrument remains the same, namely to disinfect the root canal system and prevent its recontamination. The time at which file fracture occurred during treatment and the degree of canal infection should be considered when determining the potential effect of instrument fracture on treatment outcome. Patients must be informed about an instrument fracturing in their tooth for ethical and legal reasons. The aim of this paper is to attempt to place fractured instruments in context, not to provide an in depth description of fractured instrument management techniques. CLINICAL RELEVANCE: To understand the influence of fractured instruments on prognosis in endodontics.

Protaper--hybrid technique.

UNLABELLED: Crown down preparation is the most known and described technique since the introduction of Nickel Titanium (NiTi) rotary instruments in endodontics. This technique gives good results but has limitations, such as not addressing the initial anatomy of oval or dumb-bell shaped canals. The specific design of the Protaper instruments allows use of them with a different technique and, specifically, with a brushing motion in the body of the canal. The recent introduction of hand Protaper files has expanded the range of application of this system, especially in curved canals. The 'hybrid technique', using rotary and hand files, and the advantages of the combination of both instruments, are clearly described in this article. Used with this technique, the Protaper is a very safe system to use, and more controllable, for both inexperienced and experienced practitioners alike, than other systems. CLINICAL RELEVANCE: To understand the precautions needed with rotary files, and how to use them to preserve the anatomy of the canal and get a tapered shaping, even in severely curved canals.