The Endodontic Complexity Assessment Tool (E-CAT): A digital form for assessing root canal treatment case difficulty.

AIMS: To develop an evidence-based, valid and reliable assessment tool that educational establishments and dental practitioners may use to assess the complexity of root canal treatment (RCT) utilizing digital advancements. The study also aimed to provide a more objective definition of the term 'uncomplicated' root canal treatment as described by the Association for Dental Education in Europe (ADEE) and the European Society of Endodontology (ESE) undergraduate curriculum guidelines for Endodontology. METHODOLOGY: The development process involved a narrative review of the literature to identify the complexity factors associated with root canal treatment on permanent teeth; an iterative development and analysis process to assess the weighting of these factors; and the programming of digital software to enhance the efficiency and user interface of the assessment form. Validation of the tool was sought with a panel of 35 specialist endodontists to assess clinical scenarios and assess the consensus inter-examiner agreement with the outcomes provided by the E-CAT. The inter-user and intra-user reliability studies were conducted with 15 dentists to evaluate the same clinical cases and by repeating the experiment 9 months later. The ease of use of the form was also assessed. RESULTS: The E-CAT was successfully developed with a total of 19 complexity criteria and hosted on a secure server under the domain of www.e-cat.uk. The tool provides a smart interactive filtering mechanism and automatic background calculation of the risk scores. Three levels of complexity were defined: class I (uncomplicated), class II (moderately complicated) and class III (highly complicated). The consensus of the panel of endodontists had excellent agreement with the outcome of the E-CAT. The inter-user and intra-user reliability was found to be 0.80 and 0.90, respectively. The average time to assess a case was 1:36 min. CONCLUSION: The E-CAT gave promising results providing an efficient and reliable platform to assess the complexity of cases undergoing root canal treatments. The study design allowed the formulation of a more objective definition to describe 'uncomplicated' root canal treatment as referred to by the ESE and ADEE guidelines. This study is advantageous for educational, public health and referral pathways.

Evidence for changing nerve growth factor signalling mechanisms during development, maturation and ageing in the rat molar pulp.

AIM: To examine rat molar pulp innervation and identify complex cellular signalling systems involving nerve growth factor (NGF) and its p75 receptors (NGFR) at different stages of development, maturation and ageing. METHODOLOGY: Decalcified mandibular first molar mesial cusps from Wistar rats of ages 0 day; 1, 2, 3, 4, 6, 9, 12 and 24 weeks (n = 5 per group) were sectioned (10 µm) and incubated with antibodies for NGF, NGFR, calcitonin gene-related peptide (CGRP) and neurofilament. Nerve densities in worn and intact regions of 3- to 24-week-old rats were compared by anova, Bonferroni and t-tests. RESULTS: During odontogenesis, differences in NGF and NGFR expression were observed, with no evidence of nerve fibres, suggesting a signalling mechanism controlling cellular differentiation and dentine formation. Tooth wear in 4-week rats was associated with reduced NGF expression and significantly decreased CGRP axons within affected odontoblast regions. The underlying subodontoblasts started expressing NGF which continued until 9 weeks. This may promote a significant increase in CGRP nerve density in affected regions. Nerve density in intact odontoblast regions increased gradually and reached significant levels in 12-week rats. Reduction in nerve densities within worn and intact regions of cusps was observed at 24 weeks. CONCLUSIONS: Age-related changes and responses to tooth wear may be controlled by the NGF signalling mechanism, with roles in odontoblast/subodontoblast communication and control of sensory innervation at different stages of tooth development, maturation and ageing. Greater understanding of cellular and nerve regulation in the injured pulp may promote therapeutic strategies for pulp survival.

Evidence for programmed odontoblast process retraction after dentine exposure in the rat incisor.

OBJECTIVE: To re-examine the morphology and potential functions of odontoblasts in intact rat incisors and after cavity preparation into dentine. DESIGN: Intact incisors were fixed, decalcified, snap frozen and sectioned (10µm), before staining with rhodamine phalloidin or antibodies for cyto-skeletal proteins: vimentin and actin, ion transporter: NaK-ATPase, and dendritic cell marker: OX6. Samples with cavity were processed similarly and stained for actin and vimentin before comparing the lengths of odontoblast processes (OP) at baseline, 3h and 24h (n=5 for each group). RESULTS: Actin was expressed through the full length of OP, while vimentin immunoreactivity was not uniform, with 4 distinct regions. OP showed morphological complexity with fine branches emanating within different regions of dentine. Novel actin-positive tree-like OP were identified within predentine which reduced in intensity and length toward the incisal portion of the tooth. Specimens with cavities showed time-dependant pulpal retraction of OP. CONCLUSIONS: Differences in structural antibody expression suggest functional variations in OP within different regions of dentine. The role of actin positive OP in predentine is not known, but could be related to dentine deposition, cellular stability or sensing mechanisms. Cavity preparation into dentine was followed by programmed retraction of OP which could be controlled either mechanically by the spatial limitation of the OP within dentinal tubules or structurally by the presence of vimentin, in addition to actin, in the mid-dentine.

Factors affecting direction and strength of patient preferences for treatment of molar teeth with nonvital pulps.

AIM: To elicit the factors affecting willingness to pay (WTP) values for the preferred options of participants for dealing with a molar tooth with a nonvital pulp, a common but difficult problem. METHODOLOGY: A total of 503 patients were recruited from dental practices in the North East of England and interviewed. Their preferred treatment option for a molar tooth with a nonvital pulp (endodontics, extraction and various prosthetic restorative options) and WTP for this preferred option were elicited. Factors affecting preferred option and WTP were analysed using econometric modelling. RESULTS: Overall, 53% of the sample wished to save the tooth with a mean WTP of £373. The variance in WTP was high. Of those opting for extraction, the majority chose to leave a gap or have an implant. The preferred option was influenced by previous treatment experience. WTP was only influenced by having a low income. CONCLUSIONS: The high level of variance in WTP and its relatively unpredictable nature pose difficult questions for policy makers trying to ensure the delivery of an equitable service. For dentists, it is important not to make assumptions about patient preference and strength of preference when making decisions. Ideally, WTP values should be considered alongside effectiveness data, and those on costs, in policy making.

Effect of massage on the efficacy of the mental and incisive nerve block.

The purpose of this trial was to assess the effect of soft tissue massage on the efficacy of the mental and incisive nerve block (MINB). Thirty-eight volunteers received MINB of 2.2 mL of 2% lidocaine with 1 : 80,000 epinephrine on 2 occasions. At one visit the soft tissue overlying the injection site was massaged for 60 seconds (active treatment). At the other visit the crowns of the mandibular premolar teeth were massaged (control treatment). Order of treatments was randomized. An electronic pulp tester was used to measure pulpal anesthesia in the ipsilateral mandibular first molar, a premolar, and lateral incisor teeth up to 45 minutes following the injection. The efficacy of pulp anesthesia was determined by 2 methods: (a) by quantifying the number of episodes with no response to maximal electronic pulp stimulation after each treatment, and (b) by quantifying the number of volunteers with no response to maximal pulp stimulation (80 reading) on 2 or more consecutive tests, termed anesthetic success. Data were analyzed by McNemar, Mann-Whitney, and paired-samples t tests. Anesthetic success was 52.6% for active and 42.1% for control treatment for lateral incisors, 89.5 and 86.8% respectively for premolars, and 50.0 and 42.1% respectively for first molars (P = .344, 1.0, and .508 respectively). There were no significant differences in the number of episodes of negative response to maximum pulp tester stimulation between active and control massage. A total of 131 episodes were recorded after both active and control massage in lateral incisors (McNemar test, P = 1.0), 329 (active) versus 316 (control) episodes in the premolars (McNemar test, P = .344), and 119 (active) versus 109 (control) episodes respectively for first molars (McNemar test, P = .444). Speed of anesthetic onset and discomfort did not differ between treatments. We concluded that soft tissue massage after MINB does not influence anesthetic efficacy.

Buccal versus lingual articaine infiltration for mandibular tooth anaesthesia: a randomized controlled trial.

AIM: To compare the effectiveness of buccal and lingual local anaesthetic injections in the mandibular first molar region in obtaining pulpal anaesthesia in mandibular teeth. METHODOLOGY: Twenty healthy volunteers received 1.8 mL of 4% articaine with 1 : 100,000 epinephrine as a buccal or lingual infiltration in the mandibular first molar region in a randomized double-blind cross-over design. The responses of the first molar, a premolar and the lateral incisor teeth were assessed using an electronic pulp tester over a 47-min period. Successful anaesthesia was defined as no response to maximum stimulus from the pulp tester on two or more consecutive tests. Success between techniques was analysed using the McNemar test and variations between teeth were compared with Chi-square. RESULTS: The number of no responses to maximum stimulation from an electronic pulp tester was significantly greater for all test teeth after the buccal injection compared with the lingual approach (P < 0.001). Successful anaesthesia was more likely following the buccal infiltration compared with the lingual method for molar (65% and 10%, respectively) and premolar (90% and 15%, respectively) teeth. There was no difference in anaesthetic success for the lateral incisor. CONCLUSION: Buccal infiltration at the first mandibular molar is more effective than lingual infiltration in the same region in obtaining anaesthesia of the mandibular first molar and premolar teeth.

The efficacy of infiltration anaesthesia for adult mandibular incisors: a randomised double-blind cross-over trial comparing articaine and lidocaine buccal and buccal plus lingual infiltrations.

AIM: To compare the efficacy of 2% lidocaine and 4% articaine both with 1:100,000 adrenaline in anaesthetising the pulps of mandibular incisors. METHODS: Thirty-one healthy adult volunteers received the following local anaesthetic regimens adjacent to a mandibular central incisor: 1) buccal infiltration of 1.8 mL lidocaine plus dummy lingual injection (LB), 2) buccal plus lingual infiltrations of 0.9 mL lidocaine (LBL), 3) buccal infiltration of 1.8 mL articaine plus dummy lingual injection (AB), 4) buccal plus lingual infiltrations of 0.9 mL articaine (ABL). Pulp sensitivities of the central incisor and contralateral lateral incisor were assessed electronically. Anaesthetic efficacy was determined by two methods: 1) Recording the number of episodes with no responses to maximal electronic pulp tester stimulation during the course of the study period, 2) recording the number of volunteers with no response to maximal pulp tester stimulation within 15 min and maintained for 45 min (defined as sustained anaesthesia). Data were analysed by McNemar, chi-square, Mann-Whitney and paired t-tests. RESULTS: For both test teeth, the number of episodes of no sensation on maximal stimulation was significantly greater after articaine than lidocaine for both techniques. The split buccal plus lingual dose was more effective than the buccal injection alone for both solutions (p <0.001). 4% articaine was more effective than 2% lidocaine when comparing sustained anaesthesia in both teeth for each technique (p <0.001), however, there was no difference in sustained anaesthesia between techniques for either tooth or solution. CONCLUSIONS: 4% articaine was more effective than 2% lidocaine (both with 1:100,000 adrenaline) in anaesthetising the pulps of lower incisor teeth after buccal or buccal plus lingual infiltrations.

Evaluation of the cost-effectiveness of root canal treatment using conventional approaches versus replacement with an implant.

AIM: To evaluate the cost-effectiveness of root canal treatment for a maxillary incisor tooth with a pulp infection, in comparison with extraction and replacement with a bridge, denture or implant supported restoration. METHODOLOGY: A Markov model was built to simulate the lifetime path of restorations placed on the maxillary incisor following the initial treatment decision. It was assumed that the goal of treatment was the preservation of a fixed platform support for a crown without involving the adjacent teeth. Consequently, the model estimates the lifetime costs and the total longevity of tooth and implant supported crowns at the maxillary incisor site. The model considers the initial treatment decisions, and the various subsequent treatment decisions that might be taken if initial restorations fail. RESULTS: Root canal treatment extended the life of the tooth at an additional cost of pound5-8 per year of tooth life. Provision of orthograde re-treatment, if the root canal treatment fails returns further extension of the expected life of the tooth at a cost of pound12-15 per year. Surgical re-treatment is not cost-effective; it is cheaper, per year, to extend the life of the crown by replacement with a single implant restoration if orthograde endodontic treatment fails. CONCLUSION: Modelling the available clinical and cost data indicates that, root canal treatment is highly cost-effective as a first line intervention. Orthograde re-treatment is also cost-effective, if a root treatment subsequently fails, but surgical re-treatment is not. Implants may have a role as a third line intervention if re-treatment fails.

Articaine buccal infiltration enhances the effectiveness of lidocaine inferior alveolar nerve block.

AIM: To compare mandibular tooth pulpal anaesthesia and reported discomfort following lidocaine inferior alveolar nerve block (IANB) with and without supplementary articaine buccal infiltration. METHODOLOGY: In this prospective randomized double-blind cross-over study, thirty-six healthy adult volunteers received two IANB injections of 2 mL lidocaine 2% with epinephrine 1 : 80,000 over two visits. At one visit, an infiltration of 2 mL of articaine 4% with epinephrine 1 : 100,000 was administered in the mucobuccal fold opposite a mandibular first molar. At the other visit, a dummy injection was performed. Injection discomfort was recorded on 100 mm visual analogue scales. Pulpal anaesthesia of first molar, premolar, and lateral incisor teeth was assessed with an electronic pulp tester until 45 min post-injection. A successful outcome was recorded in the absence of sensation on two or more consecutive maximal pulp tester stimulations. Data were analysed using McNemar and Student's t-tests. RESULTS: The IANB with supplementary articaine infiltration produced more success than IANB alone in first molars (33 volunteers vs. 20 volunteers respectively, P < 0.001), premolars (32 volunteers vs. 24 volunteers respectively, P = 0.021) and lateral incisors (28 volunteers vs. 7 volunteers respectively, P < 0.001). Buccal infiltration with articaine or dummy injection produced less discomfort than IANB injection (t = 4.1, P < 0.001; t = 3.0, P = 0.005 respectively). CONCLUSIONS: The IANB injection supplemented with articaine buccal infiltration was more successful than IANB alone for pulpal anaesthesia in mandibular teeth. Articaine buccal infiltration or dummy buccal infiltration was more comfortable than IANB.

Parallel post-space preparation in different tooth types ex vivo: deviation from the canal centre and remaining dentine thickness.

AIM: To determine the deviation of parallel-sided twist-drills during post-channel preparation and relate this to tooth type and position. METHODOLOGY: Human teeth with single root canals were selected: maxillary second premolars (group i); maxillary lateral incisors (group ii); mandibular canines (group iii); mandibular first premolars (group iv; all groups n = 16). The teeth were reduced to 17 mm length by sectioning the crown, and the root canals prepared and filled. Microradiographs were made in two directions. The teeth were individually embedded in a gypsum jaw and placed in a phantom head. Two operators performed parallel post-space preparation (12 mm length, 1.25 mm diameter) to the following protocol: gutta-percha removal with Gates Glidden drills numbers 2 and 3 and post-space enlargement with parallel drills numbers 3, 4 and 5, consecutively. Subsequently, microradiographs were re-exposed. The original and post-operative microradiographs were digitized and superimposed, and deviation of the post-space from the filled canal and remaining dentine thickness measured. RESULTS: Overall, the mean deviation was 0.07 mm to the mesial (95% CI: 0.01-0.12), and 0.27 mm to the buccal (95% CI: 0.18-0.35). Group ii had significantly more buccal deviation than other groups (P = 0.004-0.008). A remaining dentine thickness of <0.5 mm occurred 16 times in 14 teeth, and of <1 mm occurred 97 times in 52 teeth. CONCLUSIONS: Deviation during parallel post-preparation was common, predominantly in mesial and buccal directions, especially in maxillary incisors. This deviation increased the risk of perforation considerably.

Tutor perceptions of the use of a reflective portfolio within a pastoral tutor system to facilitate undergraduate personal development planning.

All Higher Education Institutions in the UK are now required to provide transcripts of student activity and outcomes of summative assessments. In addition, the student should be able to reflect on their learning and plan their own development. This article reports on the staff evaluation of the use of a reflective portfolio facilitating the production of highly individualised personal development plans within an existing tutor system. A number of significant issues are highlighted; tutor systems adopting this approach must maintain flexibility for managing student crises when they arise, the difference between appraisal and assessment needs clear definition for both students and tutors, training in basic mentoring skills should be provided for all tutors, tutors should be aware of the difficulties many students experience with reflection and also be alert to the over reflective learner.

Pulpal anaesthesia for mandibular permanent first molar teeth: a double-blind randomized cross-over trial comparing buccal and buccal plus lingual infiltration injections in volunteers.

AIM: To compare the efficacy of buccal and buccal plus lingual infiltration anaesthesia for permanent mandibular first molars. METHODOLOGY: Thirty one healthy adult volunteers received each of the following methods of anaesthesia for a mandibular first molar tooth in a randomised order, 1) Buccal infiltration of 1.8 mL and needle penetration lingually. 2) Buccal infiltration of 0.9 mL, plus lingual infiltration of 0.9 mL. Two percent lidocaine with 1:100,000 epinephrine was used. Electrical pulp testing was performed before, and every 2 minutes for 30 minutes after injection. A successful outcome was recorded as the absence of pulp sensation on two or more consecutive maximal pulp tester stimulations (80 microA). Injection discomfort was assessed using visual analogue scales. Data were compared with McNemar and Wilcoxon Signed Ranks tests. RESULTS: Buccal infiltration was successful in 38.7% of cases compared to 32.3% after combined infiltrations; the difference was not significant (P = 0.63). Buccal infiltration produced more episodes of no response to maximum stimulation than buccal and lingual infiltrations (129 and 114 respectively), this difference was not significant (P = 0.11). Peak anaesthetic effect occurred around 10-14 minutes after injection. There was no difference in injection discomfort between buccal injections of 0.9 mL and 1.8 mL of solution (P = 0.90). Lingual injection was more uncomfortable than lingual penetration (P = O.O02). CONCLUSIONS: Buccal and buccal plus lingual infiltrations did not differ in their efficacy in producing anaesthesia of permanent first molar teeth.

Carisolv: an alternative to NaOCl in immature root canals?

AIM: To test the null hypothesis that Carisolv is no more effective than 1% sodium hypochlorite in cleaning uninstrumented, immature root canals. METHODOLOGY: A total of 240 uniform, immature ovine incisors were decoronated at the CEJ level and randomly divided into four groups of 60. After gross pulp extirpation, canals were flooded with normal saline (negative control), 1% NaOCl, Carisolv or 5% NaOCl (positive control) and incubated for 10 min (group 1), 20 min (group 2), 30 min (group 3) or 30 min, refreshing irrigant at 10 and 20 min (group 4). SEM photomicrographs of canal wall debris in the apical, middle and coronal thirds were scored against a 5-point scale. Internal consistency was assessed by kappa statistics. Debris scores for different irrigant regimes at different canal levels were analysed by non-parametric tests (P < 0.05). RESULTS: Canals were consistently cleaner in the coronal and middle than apical thirds. NaOCl (5%) was consistently most effective. Carisolv and NaOCl (1%) were no more effective than normal saline in group 1 (P > 0.05), but significantly more effective than normal saline in groups 2 (middle and apical 1/3), 3 and 4 (P < 0.05). Carisolv and NaOCl (1%) had comparable activity in groups 1, 2 (middle and apical thirds) and 3, but NaOCl (1%) was significantly more effective than Carisolv in group 4 (coronal and middle thirds). CONCLUSIONS: 1. The ovine incisor model presents opportunities to investigate irrigation regimes under controlled ex-vivo conditions. 2.NaOCl (5%) remains the most effective irrigant for rapid debris removal in immature root canals. 3. Carisolv cleans pulp debris from the walls of immature root canals as effectively as NaOCl (1%) during static, unrefreshed wall contact for between 20 and 30 min. 4. Refreshment of NaOCl (1%) enhances its cleaning ability above that of Carisolv.

The role of nurses in telemedicine and child abuse.

Telemedicine allowed for imaging and videoconferencing between staff at a medical center hub and registered nurses who performed child abuse examinations at community hospitals. By means of electronic communication and information technology, a network was designed to facilitate the examination of children at distant locations when abuse was suspected. Telemedicine provided for expert consultation, rapid evaluation, response to community needs, and an expanded role for nurses. This anecdotal evaluation explored the experience from the view of the registered nurses and an advanced registered nurse practitioner who participated in the telemedicine network. Findings indicated that nurses went through phases of adjustments while becoming familiar with the information technology, cameras, and setup while focusing on the needs of the children and their own responses. Telemedicine nurses were able to draw upon their clinical backgrounds in caring for children and apply their knowledge and skills when assessing victims of abuse. On the basis of interviews and observation, it was concluded that telecommunication did not interfere with the nurse-patient relationship.

Pressures generated in vitro during Stabident intraosseous injections.

AIM: To test the hypothesis that the Stabident intraosseous injection is a potentially high-pressure technique, which carries serious risks of anaesthetic cartridge failure. METHODOLOGY: A standard Astra dental syringe was modified to measure the internal pressure of local anaesthetic cartridges during injection. Intra-cartridge pressures were measured at 1 s intervals during slow (approximately 15 s) and rapid (<10 s) injections of 2% Xylocaine with 1:80,000 adrenaline (0.25 cartridge volumes) into air (no tissue resistance), or into freshly prepared Stabident perforation sites in the anterior mandible of freshly culled young and old sheep (against tissue resistance). Each injection was repeated 10 times over 3 days. Absolute maximum pressures generated by each category of injection, mean pressures at 1 s intervals in each series of injections, and standard deviations were calculated. Curves of mean maximum intra-cartridge pressure development with time were plotted for slow and rapid injections, and one-way anova (P<0.05) conducted to determine significant differences between categories of injection. RESULTS: Pressures created when injecting into air were less than those needed to inject into tissue (P<0.001). Fast injection produced greater intra-cartridge pressures than slow delivery (P<0.05). Injection pressures rose more quickly and to higher levels in small, young sheep mandibles than in larger, old sheep mandibles. The absolute maximum intra-cartridge pressure developed during the study was 3.31 MPa which is less than that needed to fracture glass cartridges. CONCLUSIONS: Stabident intraosseous injection conducted in accordance with the manufacturer's instructions does not present a serious risk of dangerous pressure build-up in local anaesthetic cartridges.

Endodontic complications after plastic restorations in general practice.

AIM: To test the hypothesis that dentine and pulp protection by conditioning-and-sealing is no less effective than using a conventional calcium hydroxide lining. METHODOLOGY: A cohort of healthy adults requiring a new or replacement restoration in a posterior tooth was recruited in six general practices. All procedures received local Ethics Committee approval. Exclusion criteria included signs and symptoms of pulp necrosis or inflammation, and patients unable to commit to a long-term trial. Cavity preparations were randomized to receive a calcium hydroxide lining or conditioning-and-sealing with a smear-removing bonding system. Choice of bulk restorative material (composite resin or amalgam) was at the discretion of the dentist. The key outcome measure was evidence of pulpal breakdown identified at unscheduled (emergency) or scheduled recall examinations. Postoperative sensitivity was recorded on 100 mm VAS at 24 h, 4 days and 7 days. Pulp status was assessed at 6, 12, 24 and 36 month recall, and at any emergency recall appointment. The relationship between pre-treatment and treatment variables and pulp breakdown was assessed by logistic regression (P = 0.05). RESULTS: A total of 602 teeth were recruited, with comparable numbers of cavities lined (288, 47.8%) or conditioned and sealed (314, 52.2%). The majority (492, 81.7%) were replacement restorations, and amalgam was the most common bulk restorative material (377, 62.6%). A total of 390 (64.8%) restored teeth were reviewed at 6 months, 307 (51%) at 12 months, 363 (60.3%) at 24 months, and 279 (46.3%) at 36 months post-restoration. Sixteen cases of pulp breakdown were identified within 36 months of restoration placement, 11 presenting as emergencies and five detected at routine recall examination. Logistic regression showed that preoperative pain, cavity treatment by lining or conditioning-and-sealing and the use of rubber dam isolation had no association with pulp breakdown. Pulp breakdown was associated with deep or pulpally exposed cavities (P < 0.001, odds ratio 7.8) and with composite rather than amalgam restorations (P = 0.001, odds ratio 2.13). Re-coding to identify teeth with pulp exposures revealed that pulpal exposure was the key determinant of adverse pulp outcomes (P < 0.0001, odds ratio 28.4) and that composite resin restorations were again more likely to be associated with pulp breakdown than amalgam (P = 0.017, odds ratio 3.92). CONCLUSIONS: Considered within the context of routine primary dental care: Dentists can be confident that pulps will be equally well protected from post-restorative breakdown up to 36 months by calcium hydroxide lining and conditioning-and-sealing with adhesive resins. Residual dentine thickness appears to be a key determinant of pulp responses after restorative dental treatment. In deep and pulpally exposed cavities in posterior teeth, composites were associated with more pulpal breakdown than amalgams.

Antibiotic prophylaxis for patients with joint prostheses - still a dilemma for dental practitioners.

OBJECTIVES: To provide a critical review of the current evidence that implicates dental-induced bacteraemia as a risk for joint infections in patients fitted with joint prostheses and appraise the need for antibiotic prophylaxis. DESIGN: Retrospective analysis. SETTING: Mainly hospital-based patients or subjects. OUTCOME MEASURES: The relationship between joint infections and dental treatment is equivocal at the best and there is no evidence that antibiotic prophylaxis provides such patients with any protection. RESULTS: Microbiological evidence linking dental treatment-induced bacteraemia to joint infections is weak and if an oral commensal is implicated, it is more likely to have arisen either from a spontaneous bacteraemia or from a dental infection. As a consequence of the latter, we recommended the institution of good dental health prior to joint replacement. There may be a case for providing prophylaxis to the immuno-compromised patient, but only if the immuno-suppression is associated with a neutropenia. In such circumstances, only emergency treatment should be considered until the neutropenia is resolved. Antibiotic regimens that are recommended by orthopaedic surgeons have not been evaluated in a randomised placebo-controlled study and many of the drugs are not licensed for this purpose. The evidence on cost-risk benefit seems to demonstrate that antibiotic prophylaxis with either amoxicillin or penicillin is not cost effective when compared with no prophylaxis. CONCLUSION: The case for providing antibiotic prophylaxis prior to dental treatment in patients fitted with a joint prosthesis is weak or virtually non-existent. Furthermore, the risk from providing prophylaxis is greater than the risk of a joint infection.

Preliminary in vitro evaluation of Carisolv as a root canal irrigant.

AIM: To test the null hypothesis that Carisolv is no better than PBS in removing organic debris from uninstrumented root canals. METHODOLOGY: The pulps of two uniform groups of 36 immature, sheep mandibular incisors were grossly removed with barbed broaches immediately prior to the study. Roots in group 1 were irrigated with phosphate buffered saline (PBS), strong sodium hypochlorite (4.5%) or Carisolv without ultrasonic agitation, whilst in group 2 the same irrigants were activated with ultrasound. Canal walls were exposed to irrigants for 10, 20 or 30 min at 37 degree C. In group 2, ultrasound was applied for 30 s at 2, 5 and 7 min within each 10 min incubation period. After washing irrigants free and immersion in fixative, all teeth were split longitudinally, critical point dried and sputter coated for SEM analysis. SEM photomicrographs were recorded of representative areas in the coronal, middle and apical canal thirds and debris scored by a single assessor against a five-point scale. Intraobserver reliability was assessed by Cohens kappa scores and debris scores analysed by the non-parametric Kruskal-Wallis test at P < 0.05. RESULTS: Sodium hypochlorite was significantly better than Carisolv and PBS in cleaning root canals (P < 0.0001), whether or not ultrasound was applied. Carisolv was shown to clean canals better than PBS, again whether or not ultrasound was applied (P = 0.01). Both incubation time and ultrasound enhanced the action of Carisolv (P < 0.001) whilst the activity of PBS was not significantly improved by exposure time or the application of ultrasound. Kappa scores of 0.90-0.95 indicated excellent consistency in debris scoring. CONCLUSIONS: Within the limitations of this preliminary study (i). Carisolv cleaned root canals better than PBS and shows promise as an adjunct to root canal preparation; (ii). the action of Carisolv was enhanced by incubation times beyond 20 min whether or not ultrasound was applied; (iii). sodium hypochlorite solution remains the gold standard endodontic irrigant, provided that it is used with care and is contained in the canal system.

Prostaglandin E2 and treatment outcome in pulp therapy of primary molars with carious exposures.

OBJECTIVES: Prostaglandin E2 (PGE2) has been suggested as an indicator of irreversible pulpitis in permanent teeth [1]. There is scant information on the role of chemical mediators in primary molar pulp inflammation. The aim of this preliminary study was to investigate the levels of PGE2 in blood harvested from root pulp stumps following coronal pulp amputation in vital primary molar teeth with carious exposures. METHODS: Seventy-nine cariously exposed primary molars underwent treatment by one of two vital pulp therapy techniques. Blood was harvested from 38 teeth and volume and concentration of PGE2 ([PGE2]) determined [2]. Treatment outcome was assessed from both clinical and radiographic evidence. RESULTS: PGE2 was detected in all samples, with a wide concentration range (1-2641 ng/mL). The distribution was skewed, requiring log transformation. The difference in the mean (log) [PGE2] for radiological success (3.12, SD 1.60 and failure (4.62, SD 1.80) was significant, t = 2.05, P = 0.047. The difference in the mean (log) [PGE2] for clinical success (3.24, SD 1.65) and failure (5.44, SD 1.43 was near-significant, t = 1.84, P = 0.074. CONCLUSION: [PGE2] correlated positively with radiological outcome following vital pulp therapy.