Patient satisfaction with root canal treatment and outcomes in the Swedish public dental health service. A prospective cohort study.

AIM: To document satisfaction with root canal treatment procedures and outcomes among patients treated at Swedish public dental clinics. METHOD: The original material comprised 243 patients who began root canal treatment (RCT) at 20 public dental clinics in the county of Västra Götaland, Sweden. One to three years later, 236 (97.1%) were posted a questionnaire of eight items, rating patient perceptions of RCT-completion, present pain intensity and satisfaction with the RCT. To evaluate the reliability of the original responses, the first 50 respondents were mailed a follow-up questionnaire. Both descriptive and analytical statistics were used to compare respondents and non-respondents and tooth groups. RESULTS: One hundred and fifty-nine patients (67.4%) responded: 86 (54.1%) women and 73 (45.9%) men. The mean age 52.5 years, was higher than for non-respondents (P<0.001). A completed root filling was registered for the majority of the teeth (n = 112, 70.9%), but significantly fewer molars had been completed (n = 46, 59.7%, P = 0.02). Fifty percent (n = 59) of the patients reported current pain, mostly mild in intensity (n = 45, 38.1%). One hundred and twenty-three patients (80.9%) recalled experiencing pain during RCT. The highest satisfaction was registered for the item 'chewing ability' (mean = 1.6, SD = 1.9). The majority of patients (n = 114, 75.0%) stated that in retrospect they would still have chosen RCT. However, these patients belonged to the group which either registered the tooth as still present, or had not experienced much discomfort during or after RCT. Forty-four patients (88.0%) responded to the second questionnaire. The reliability of the responses was good. In summary, one to 3 years after beginning RCT at a public dental clinic, patient satisfaction was high, even though every fourth molar had been extracted or treatment had not been completed and half the patients reported persistent pain. The reliability of the patients' responses was considered to be good. CONCLUSIONS: The results indicate a need for further clinical observational studies of RCTs undertaken in general dental practice, with special reference to patient-centred outcomes.

Factors Associated with Extraction following Root Canal Filling in Adults.

Essentially, root fillings are performed to preserve natural teeth. Over time, however, some root-filled teeth will inevitably be extracted. The aim of this historical prospective cohort study in the adult Swedish population was to identify factors associated with extractions within 5 y of registration of a root filling. The cohort consisted of all those whose root fillings had been reported to the tax-funded Swedish Social Insurance Agency (SSIA) in 2009. Demographic data on the individuals registered with a root filling (sex, age, country of birth, disposable income, educational level, and marital status) were received from Statistics Sweden or the SSIA. Dental care setting, tooth type, and any registration of subsequent restorations within 6 mo were received from the SSIA. Multivariable regression analysis was used, and P < 0.05 was considered statistically significant. In total, 216,764 individuals had been registered with at least 1 root filling. Individuals (n = 824) without complete data were excluded from the analyses. After 5 y, 9.3% of the root-filled teeth had been registered as extracted. Logistic regression analysis found significant associations for all variables except country of birth, disposable income, and educational level. The highest odds ratios for extractions were associated with the type of restoration: teeth with no registration of any restoration and teeth with a direct restoration combined with a post were 3 times more likely to undergo extraction than teeth restored with an indirect restoration combined with a post and core. Overall, high odds ratios for extractions were associated with any type of composite restoration, including composite fillings and crowns combined with or without any post. In summary, after root filling in the Swedish adult population, several individual- and tooth-specific variables were associated with extraction. The reasons for the extractions remain to be studied further.

PRIRATE 2020 guidelines for reporting randomized trials in Endodontics: explanation and elaboration.

Well-designed and properly conducted randomized clinical trials provide a true estimate of the effects of interventions and are acknowledged as the gold standard in terms of clinical study design. However, the quality of randomized clinical trials published in the field of Endodontics is suboptimal. The Preferred Reporting Items for RAndomized Trials in Endodontics (PRIRATE) 2020 guidelines were developed exclusively for Endodontics by integrating and adapting the CONsolidated Standards of Reporting Trials (CONSORT) statement and Clinical and Laboratory Images in Publications (CLIP) principles, through an accepted and well-documented consensus process. Full implementation of the PRIRATE 2020 guidelines will minimize potential sources of bias and thus enhance the standard of manuscripts submitted for publication, which will ultimately improve the reporting of randomized clinical trials in Endodontics. The aim of this document is to provide an explanation for each item in the PRIRATE 2020 checklist and flowchart with examples from the literature in order to help authors understand their rationale and significance. A link to this PRIRATE 2020 explanation and elaboration document is available on the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website at http://www.pride-endodonticguidelines.org/prirate/.

PRIRATE 2020 guidelines for reporting randomized trials in Endodontics: a consensus-based development.

In evidence-based health care, randomized clinical trials provide the most accurate and reliable information on the effectiveness of an intervention. This project aimed to develop reporting guidelines, exclusively for randomized clinical trials in the dental specialty of Endodontology, using a well-documented, validated consensus-based methodology. The guidelines have been named Preferred Reporting Items for RAndomized Trials in Endodontics (PRIRATE) 2020. A total of eight individuals (PD, VN, HD, LB, TK, JJ, EP and SP), including the project leaders (PD and VN) formed a steering committee. The committee developed a checklist based on the items in the Consolidated Standards of Reporting Trials (CONSORT) guidelines and Clinical and Laboratory Images in Publications (CLIP) principles. A PRIRATE Delphi Group (PDG) and PRIRATE Face-to-Face Meeting group (PFMG) were also formed. Thirty PDG members participated in the online Delphi process and achieved consensus on the checklist items and flowchart that make up the PRIRATE guidelines. The guidelines were discussed at a meeting of the PFMG at the 19th European Society of Endodontology (ESE) Biennial congress, held on 13 September 2019 in Vienna, Austria. A total of 21 individuals from across the globe and four steering committee members (PD, VN, HD and LB) attended the meeting. As a consequence of the discussions, the guidelines were modified and then piloted by several authors whilst writing a manuscript. The PRIRATE 2020 guidelines contain a checklist consisting of 11 sections and 58 individual items as well as a flowchart, considered essential for authors to include when writing manuscripts for randomized clinical trials in Endodontics.

Immediate clinical and microbiological evaluation of the effectiveness of 0.5% versus 3% sodium hypochlorite in root canal treatment: A quasi-randomized controlled trial.

AIM: To test the hypothesis that in the daily routine of a specialist clinic in endodontics that irrigation during root canal preparation with 3.0% NaOCl will result in fewer postoperative samples with cultivable bacteria than irrigation with 0.5% buffered NaOCl but, at the same time, will not result in a higher frequency of postoperative pain nor swelling. METHODOLOGY: Two hundred ninety-eight patients were enrolled in the study and were randomly assigned into two groups - 0.5% NaOCl and 3% NaOCl. All endodontic diagnoses were included. Root canal treatment was performed, and bacterial sampling was carried out prior to root filling. The patients were requested to complete a form regarding pain and swelling seven days postoperatively. Fisher's exact test, Mann-Whitney U-test, Mantel-Haenszel chi-squared and the chi-squared test with a significance level of P < 0.05 were used for statistical analysis. Multivariable logistic regression was used to adjust for confounders. RESULTS: In the 0.5% NaOCl group, 18 (13.4%) of the root canal samples were positive; in the 3% NaOCl group, the corresponding number was 24 (18.6%). The mean difference of -5.2% (95% CI: -14.8 to 4.4) was not significant (P = 0.33). In the 0.5% NaOCl group, 57 (53.8%) patients reported some pain; in the 3% group, the corresponding number was 56 (53.3%). The mean difference of 0.4 (95% CI: -14.0 to 14.8) was not significant (P = 1.0). In the 0.5% NaOCl group, 5 (5.1%) patients reported swelling; in the 3% NaOCl group, the corresponding number was 18 (17.8%). The mean difference was 12.7 (95% CI: 3.1-22.4), which was significant (P = 0.0084). CONCLUSIONS: The difference in the concentration of NaOCl (0.5% vs 3%) had no significant impact on the number of positive cultures and did not influence either the frequency or the magnitude of postoperative pain. A significantly higher incidence of postoperative swelling was recorded for patients who received a greater concentration of NaOCl (3%).

The frequency and characteristics of pain and discomfort associated with root filled teeth: a practice-based study.

AIM: To (i) investigate the frequency and characteristics of pain and discomfort associated with root filled teeth in adult patients regularly attending the Public Dental Service in Örebro County, Sweden; (ii) assess the association between symptoms and clinical and radiographic findings; and (iii) explore the impact of pain and discomfort from root filled teeth on daily life. METHODOLOGY: Patient records of adult patients (≥20 years) scheduled for routine check-ups in April 2015 were screened to identify individuals with root filled teeth; all patients with ≥1 root filled tooth were asked to participate. The examination comprised of clinical and radiographic examinations and questionnaires on general health, on pain symptoms from root filled teeth and on the impact of pain on daily activities. In a general estimating equation (GEE), examination findings and patient-related factors were independently analysed in relation to the outcome 'presence of pain'. RESULTS: In total, 550 patients with 1256 root filled teeth participated. Fifty-three patients (9.6%) experienced pain or discomfort from 62 (4.9%) root filled teeth. Lower age, percussion tenderness and apical tenderness were significantly associated with pain (P > 0.001 to P = 0.044). The average pain intensity was 2.1 on a (0-10) Numeric Rating Scale, and average duration was 28.4 months. The impact on daily life was low. CONCLUSIONS: On average, pain associated with root filled teeth was of mild intensity, >2 years of duration and had low impact on daily life. Although the significantly associated clinical findings may indicate apical periodontitis as the most probable explanation in some teeth, the origin of pain from root filled teeth remains partly unexplained.

Preferred Reporting Items for RAndomized Trials in Endodontics (PRIRATE) guidelines: a development protocol.

Randomized clinical trials are acknowledged as the most appropriate methodology for demonstrating the efficacy or effectiveness of one intervention as opposed to another and thus play a major role in clinical decision-making. However, it is recognized that despite the existence of various guidelines, for example, the Consolidated Standards for Reporting Trials (CONSORT) statement, the quality of manuscripts describing randomized trials is often suboptimal. The current project aims to develop and disseminate new guidelines, Preferred Reporting Items for RAndomized Trials in Endodontics (PRIRATE), to improve the planning and reporting quality of randomized trials in the field of Endodontics. The project leads (VN, PD) designed a robust process to develop the PRIRATE guidelines. At first, a steering committee of eight members, including the project leads, was formed. Thereafter, a five-stage consensus process will be followed: initial steps, pre-meeting activities, face-to-face consensus meeting, post-meeting activities and post-publication activities. The steering committee will develop the first draft of the PRIRATE guidelines by identifying relevant and important items from various sources including the CONSORT guidelines and the Clinical and Laboratory Images in Publications (CLIP) principles. This will be followed by the establishment of a PRIRATE Delphi Group (PDG) consisting of 30 members. The individual items of the first draft of the PRIRATE guidelines developed by the steering committee will be evaluated and scored on a 9-point Likert scale by the PDG members. Items with a score of seven and above by more than 70% of PDG members will be included in the second draft of the guidelines, and the Delphi process will be repeated until each item fulfils the set conditions. After obtaining consensus from the PDG, the PRIRATE guidelines will be discussed by 20 selected individuals within a PRIRATE Face-to-face Consensus Meeting Group (PFCMG) to arrive at a final consensus. The final PRIRATE guidelines will be accompanied with an explanation and elaboration document developed by the steering committee and approved by six members, three from the PDG and three from the PFCMG. The PRIRATE guidelines will be published in journals and actively disseminated to educational institutions, national and international academic societies and presented at scientific meetings. The steering committee will periodically revise and update the PRIRATE guidelines based on feedback from stakeholders.

Indications for root canal treatment in a Swedish county dental service: patient- and tooth-specific characteristics.

AIM: To study patient- and tooth-specific characteristics of teeth indicated for root canal treatment, in the public dental service of the county of Västra Götaland, Sweden. METHODOLOGY: During a designated 8-week period, general dental practitioners working at 20 different public dental clinics consecutively registered indications for undertaking root canal treatment. The patients' subjective level of pain was also registered (visual analogue scale) at the very first appointment. The following information was retrieved from computerized dental records and radiographs: gender, age, number of remaining teeth, tooth group, previous restoration, number of restored surfaces, dental caries and tooth substance loss. Gender and age were compared using both descriptive and analytical statistics. RESULTS: The material comprised 243 teeth in 243 patients: 128 (52.7%) women and 115 (47.3%) men, mean age 48.3 years. Molar teeth predominated (47.7%). Most of the teeth (83.5%) had previously been restored and exhibited significant loss of tooth substance, more than a third of the crown (71.3%). Dental caries was present in 127 teeth (62.9%). Dental trauma was implicated in only seven cases (2.9%). Initial treatment was frequently undertaken at an emergency visit, for relief of symptoms (64.9%). The most commonly registered indication was pulpal necrosis with apical periodontitis (38.1%), followed by pulpitis (37.7%). Retreatment of a root filled tooth was reported in 18 teeth (7.4%). CONCLUSIONS: In the general Public Dental Service of Sweden, root canal treatment is most frequently undertaken in molars. The primary indication is relief of symptoms. Retreatment of root filled teeth is uncommon.

Demographic factors in Swedish adults undergoing root filling and subsequent extraction of a maxillary first molar: a comparative study.

AIM: To study the demographics of Swedish adults who had received a root filling, followed by extraction during the following 5-6 years in comparison with subjects who had undergone a corresponding root filling with an uneventful outcome. METHODOLOGY: The root filled maxillary first molar was chosen as the comparison model. The Swedish Social Insurance Agency provided data on all teeth reported as root filled in Sweden during 2009. A comparison group, equally large as the study group, was constructed by randomly selecting subjects with root filled maxillary first molars, which had not subsequently been extracted, that is, an uneventful outcome. Demographic data on the subjects were obtained from Statistics Sweden: country of birth, disposable income, educational level, age, civil status and gender. Chi-square, t-tests and logistic regression were used for statistical analyses. RESULTS: In the year 2009, 36 139 maxillary first molar teeth were reported to have been root filled, 4362 (12.1%) of which were then recorded as extracted during the following 5-6 year period. Only minor intergroup differences were noted: 86.5% of the study group were Swedish-born, compared with 84.4% of the comparison group (P = 0.007). Women comprised 53.2% of the study group and 50.5% (P = 0.01) of the comparison group. There was an association between extractions and gender as well as age; men had a lower odds ratio (OR) for extraction OR, 0.87; confidence interval (CI), 0.80-0.95. For every additional year, the chance for extraction was higher OR, 1.01; CI, 1.01-1.01. No other significant differences were detected. CONCLUSIONS: There was only little or no demographic differences between the study group, comprising Swedish adults who had undergone root filling of one of their maxillary first molars in 2009 and subsequent extraction during the following 5-6 years, and the comparison group, with uneventful outcomes after a corresponding root filling.

Oral health in children investigated by Social services on suspicion of child abuse and neglect.

Child abuse and neglect (CAN) are likely to have negative consequences on health; however, for oral health, studies on associated outcomes are sparse. The purpose of this study was to assess oral health and oral health behaviors in relation to suspected CAN among children being investigated by the Swedish Social Services. The material comprised data from the Social Services and dental records; the sample, 86 children and 172 matched controls. The children in the study group had a higher prevalence of dental caries than the control group; in addition, levels of non-attendance and dental avoidance were high, as was parental failure to promote good oral health. We found four factors that, taken together, indicated a high probability of being investigated because of suspected CAN: prevalence of dental caries in primary teeth, fillings in permanent teeth, dental health service avoidance, and referral to specialist pediatric dentistry clinics. If all four factors were present, the cumulative probability of being investigated was 0.918. In conclusion, there is a high prevalence of dental caries, irregular attendance, and a need for referral a pediatric dental clinic among Swedish children under investigation due to suspected CAN. Social context is an important factor in assessing the risk of developing dental caries, the inclination to follow treatment plans, and the prerequisites for cooperation during treatment. Routinely requesting dental records during an investigation would provide important information for social workers on parental skills and abilities to fulfill the basic needs of children.

Comparative analysis of general dental practitioners' fees and scheduled fees for root canal treatment and coronal restorations in the adult population of Sweden: a 5-year follow-up of data from the Swedish Dental Register.

AIM: To investigate the fees charged by Swedish dentists for root fillings, coronal restorations and further dental interventions during a follow-up period of 5-6 years. METHODOLOGY: A total of 248 299 root fillings were linked with the tooth, the patient and the provider and entered into the Swedish Social Insurance Agency register in 2009. The data register also recorded the subsidy-based (scheduled) fee and the fee actually charged for the root fillings. Fees charged for direct or indirect coronal restorations and additional interventions during the follow-up period were also recorded. One-way anova and t-test were used for statistical analysis. RESULTS: The mean overall fee charged for a root filling was approximately 332 Euro and differed only marginally (13 Euro) from the scheduled fee. The total mean fee for preservation of a root filled tooth was 717 Euro, which included the root canal treatment, the coronal restoration and any additional interventions during the follow-up period. The fees for indirectly restored root filled teeth were significantly higher (1105 Euro) than for directly restored teeth (610 Euro), despite further additional treatment (P < 0.001). The mean fee for teeth which were subsequently extracted was higher (769 Euro) than for the retained teeth (711 Euro) (P < 0.001). CONCLUSIONS: Fees charged by Swedish dentists for root canal treatment were in accordance with the scheduled fees. The overall mean fee was significantly higher for root filled teeth with indirect restorations than for teeth with direct coronal restorations. However, prospective clinical cost-effectiveness studies are needed to analyse the total costs.

The role of the P2X7 receptor on bone loss in a mouse model of inflammation-mediated osteoporosis.

In inflammatory autoimmune diseases, bone loss is frequent. In most cases, secondary osteoporosis is caused by treatment with systemic glucocorticoid. However, the pathogenesis behind the bone loss is presumed multifactorial. We aimed to elucidate the role of the P2X7 receptor on bone mineral density (BMD), microarchitecture, and bone strength in a standardized mouse model of inflammation-mediated osteoporosis (IMO). In total 146 mice completed our protocol, 70 wild type (WT) mice and 76 P2X7 -/- (knockout, KO). BMD at the femur and spine decreased significantly from baseline to day 20 in the WT IMO mice (p < 0.01). In the WT vehicle, KO vehicle and KO IMO, no significant BMD changes were found. Bone strength showed a lower mid-shaft max strength (p = 0.038) and also a non-significant trend towards lower strength at the femoral neck of the WT IMO group. Trabecular bone volume fraction (BV/TV) and connectivity density (CD) after 20 days were significantly decreased in the WT IMO group (p = 0.001). In contrast, the WT vehicle and KO vehicle, BV/TV and CD did no change at 20 days. Cortical bone revealed no significant microarchitectural changes after 20 days in the WT IMO group, whereas the total cortical area increased significantly in WT vehicle and KO IMO after 20 days (5.2% and 8.8%, respectively). In conclusion, the P2X7 receptor KO mice did not respond to inflammation with loss of BMD whereas the WT mice had a significant loss of BMD, bone strength and trabecular microarchitecture, demonstrating a role for the P2X7 receptor in inflammatory bone loss.

Characteristics of teeth referred to a public dental specialist clinic in endodontics.

AIM: To investigate referrals to a specialist clinic in endodontics in relation to previously root filled teeth and to determine how many of these teeth had a history of symptoms and the extent to which antibiotics were prescribed. METHODOLOGY: The total number of referrals to the specialist clinic in endodontics in Gothenburg, Sweden, in 2011 was investigated retrospectively by means of patient records. The endodontic status together with the presence or absence of symptoms was registered. The following variables were also examined: gender, age, tooth number and lower or upper jaw. Additionally for root filled teeth, the type of restoration, the technical quality of the root filling and the presence of apical periodontitis were registered. The use of antibiotics was examined for all of the included teeth. Statistical analysis was performed using generalized estimating equation methods applied to univariable and multivariable logistic regression. RESULTS: A total of 1117 patient records were investigated, including 1341 referred teeth. Pain and/or swelling were recorded for 658 (54.3%) teeth. Symptoms were significantly more associated with females (P < 0.0001) and molar teeth (P < 0.0001). Seven hundred twenty-nine (54.4%) of the referred teeth were root filled, and of these, 377 (56.0%) were associated with pain and/or swelling. Root filled teeth restored with a post and core were less frequently related to symptoms (P = 0.009). One hundred sixty-two (22.3%) root filled teeth were treated with antibiotics, which was significantly more frequent than for non-root filled teeth (P < 0.0001). Also, root filled teeth with an adequate root filling were significantly associated with more frequent antibiotics prescriptions (23.8%) than root filled teeth with an inadequate root filling (17.0%) (P = 0.0010). CONCLUSION: Root filled teeth constituted the majority of cases referred to this specialist clinic in endodontics. The majority of these teeth were associated with symptomatic conditions, and antibiotics were prescribed to approximately 20% of the patients referred for a root filled tooth. The findings suggest that symptomatic root filled teeth may be a substantial clinical problem in general dentistry and contribute to avoidable prescription of antibiotics.

The DanCavas Pilot Study of Multifaceted Screening for Subclinical Cardiovascular Disease in Men and Women Aged 65-74 Years.

OBJECTIVE/BACKGROUND: This pilot study of a large population based randomised screening trial investigated feasibility, acceptability, and relevance (prevalence of clinical and subclinical cardiovascular disease [CVD] and proportion receiving insufficient prevention) of a multifaceted screening for CVD. METHODS: In total, 2060 randomly selected Danish men and women aged 65-74 years were offered (i) low dose non-contrast computed tomography to detect coronary artery calcification (CAC) and aortic/iliac aneurysms; (ii) detection of atrial fibrillation (AF); (iii) brachial and ankle blood pressure measurements; and (iv) blood levels of cholesterol and hemoglobin A1c. Web based self booking and data management was used to reduce the administrative burden. RESULTS: Attendance rates were 64.9% (n = 678) and 63.0% (n = 640) for men and women, respectively. In total, 39.7% received a recommendation for medical preventive actions. Prevalence of aneurysms was 12.4% (95% confidence interval [CI] 9.9-14.9) in men and 1.1% (95% CI 0.3-1.9) in women, respectively (p < .001). A CAC score > 400 was found in 37.8% of men and 11.3% of women (p < .001), along with a significant increase in median CAC score with age (p = .03). Peripheral arterial disease was more prevalent in men (18.8%, 95% CI 15.8-21.8) than in women (11.2%, 95% CI 8.7-13.6). No significant differences between the sexes were found with regard to newly discovered AF (men 1.3%, women 0.5%), potential hypertension (men 9.7%, women 11.5%), hypercholesterolemia (men 0.9%, women 1.1%) or diabetes mellitus (men 2.1%, women 1.3%). CONCLUSION: Owing to the higher prevalence of severe conditions, such as aneurysms and CAC ≥ 400, screening for CVD seemed more prudent in men than women. The attendance rates were acceptable compared with other screening programs and the logistical structure of the screening program proved successful.

Retrograde root canal treatment: a prospective case series.

AIM: Root canal treatment of teeth with necrotic pulps and apical periodontitis may be complicated by limited access to the root canals due to restorations and dystrophic calcifications. The objective of this study was to evaluate retrograde root canal as a primary treatment using a surgical approach as an alternative to conventional orthograde treatment. METHODOLOGY: Patients with apical periodontitis in the anterior region of the maxilla were consecutively recruited to the study over a period of 4 years. Fifty-seven patients met the inclusion criteria and received retrograde root canal treatment. A clinical and radiographic evaluation was made after 1 and 2 years postoperatively. RESULTS: Clinical and radiographically evaluation after 2 years revealed a successful outcome (as defined in this study) in 90% of the cases. CONCLUSION: Retrograde root canal as a primary treatment was a reliable alternative to treat apical periodontitis on single- and two-rooted teeth with limited orthograde access to the root canals in the maxilla.

Rapid and reliable method for identification of associated endonuclease cleavage and recognition sites.

UNLABELLED: One barrier to cross during genetic engineering is the restriction-modification system found in many bacteria. In this study, we developed a fast and reliable method for mapping the recognition and cleavage site of the restriction endonucleases. Clostridium pasteurianum, a model organism for the study of nitrogen fixation, has been found to harbour at least two restriction-modification systems including the restriction endonucleases CpaPI, which is an isoschizomer of MboI and CpaAI. Dam-methylated DNA was used to isolate the activity of CpaAI. Exposing freshly prepared cell lysate to known nucleotide fragments and directly sequencing the pool of digested nucleotide fragments enabled identification of the cleavage sites in the fragments. By aligning the sequences adjacent to the cleavage site, it was possible to identify the recognition sequence. Using this method, we successfully located all CpaAI recognition and cleavage sites within the template sequence. By modifying DNA with both Dam and CpG methylases (M.SssI) and thereby preventing digestion by CpaPI and CpaAI, no further endonuclease activity was detected. SIGNIFICANCE AND IMPACT OF THE STUDY: Restriction-modification systems are important barriers to successful genetic modification in many bacterial species. In this study, we demonstrate an efficient and general applicable method for identifying endonuclease recognition and cleavage sites. For the study and the trails, the model organism for nitrogen fixation Clostridium pasteurianum was used. The method was proven to be reliable, and by modifying DNA at the identified sites, it is possible to prevent digestion.

Is treatment under general anaesthesia associated with dental neglect and dental disability among caries active preschool children?

AIM: To study if treatment under general anaesthesia (GA) is associated with dental neglect or dental disability. STUDY DESIGN: This was a retrospective study. METHODS: Dental records of all children in the age 0-6 years who underwent GA at a specialist paediatric dentistry clinic during 2006-2011 were studied with regard to decayed-missed-filled teeth, traumatic injuries, emergency visits, behaviour management problems and the history of attendance. The final sample consisted of 134 children. Matched controls were selected among recall patients who had not received treatment under GA. STATISTICS: Fishers exact test or Pearson Chi-square test analysed response distribution and comparisons between groups, and for multivariate analyses, logistic regression was used. RESULTS: The results show that children treated under GA had significantly higher caries prevalence, apical periodontitis and infections due to pulpal necrosis. Dental neglect as well as dental disability was significantly more prevalent in the GA group compared to the control group. In a multivariate analysis with dental neglect as independent factor, dental disability was the only significant factor (p = 0.006). CONCLUSIONS: Children treated under general anaesthesia were significantly more often diagnosed with both dental neglect and dental disability. Dental disability was the only factor significantly related to dental neglect. There is a need for improved documentation in the dental records to better identify dental neglect and dental disability, and also a continued training of dentists regarding child protection.