Fifteen-year survival of root canal treated teeth in England and Wales

Objective Investigate the fifteen-year survival curve for root treated teeth in adult patients treated within the National Health Service General Dental Services (NHS GDS) in England and Wales by General Dental Practitioners (GDPs). Methods The data source was the age-stratified random sample of NHS GDS patients and the treatments they received over the period from 1990 to 2006 (SN7024 from https://ukdataservice.ac.uk). The survival was measured to reintervention which was categorised as re-root canal treatment, root-end surgery (apicectomy) or extraction after root canal treatment (RCT). Analysis was carried out using modified Kaplan- Meier methodology to establish survival curves extending to fifteen years and investigation of factors that can affect survival. Results The 15 years survival of root canal treated teeth by GDPs was 77% based on reintervention for 791,375 RCT teeth from over 2.5 million patients, whilst based on extraction the 15-year survival was 83%. The investigation of factors that affect survival were carried out and indicated that there were some dentist, patient and tooth factors of significance. The dentists in their 30s had the best survival outcome whilst the opposite was evident for dentists aged 60 and above, also dentists working in South Central England had markedly better results than those in Wales. The age of the patient and the full charge paying status of the patient were also significant factors. The tooth factors investigated revealed better survival among posterior teeth, lower teeth, and those restored after RCT with a crown, bridge abutment and pin/screw. A previous history of RCT, post, crown and bridge abutment decreased the survival of the RCT teeth. Occlusal restorations also decreased the survival both before and after RCT. Conclusion The 15 years survival of root canal treated teeth carried out on 791,375 teeth by GDPs in England and Wales was 77% based on reintervention and 83% based on extraction. These findings are encouraging and appear to support the provision of RCT by GDPs working in the NHS GDS to save teeth. Two dentist factors, two patient factors plus tooth factors including the tooth position and nine types of restorations were found to be significant

COMPARISON OF NEW MATHEMATICS TEACHING METHODS WITH TRADITIONAL METHOD

The aim of this paper is to compare the mathematics teaching methods, and study their consequences on mathematics learning. Numerous studies have shown that students experience mathematics anxiety which is a feeling of tension and fear that interfere with math learning. This may be attributed to the applied teaching methods in the classrooms. The three major teaching methods are: traditional, problem-solving, and discovery learning. Traditional teaching method is a teacher-centered instruction, while problem-solving method is a as teacher and student-centered which is based upon how teacher uses the four steps of problem-solving methods in teaching Mathematics. In discovery learning method, teacher plays the role of facilitator through involving students in varied activities associated with the discovery and construction of the knowledge. The qualitative case study method was considered more feasible and appropriate to meet the aim of this study. Data were collected using observation and semi-structured interviews with teachers in the secondary schools in Malaysia. It was observed that traditional, problem solving and discovery learning methods were practiced by the teachers. The findings reveal that students are more successful when systematic problem solving method based on Polya’s approach is incorporated into discovery learning. Consequently, there should be more emphasis on teaching methods which include less lecture, more student-centered classes and more discussion. The findings suggest that problem solving and discovery methods not only contribute to better mathematics learning but also enhance students’ creativity to cope with life challenge

DECISION ANALYSIS IN CONSTRUCTION CLAIMS

Claims in construction projects are inevitable and can result in costly litigation. Construction contract ambiguity, overly restrictive terms, and unfairly allocated risks are among the factors increasing the likelihood of conflict between parties in construction claims. The source of conflict is a gap between parties’ beliefs over specifics of a claim. This research introduces a settlement negotiation model that provides methods for disagreeing parties to understand the gaps in their beliefs and possibly to come to an agreement before litigation. The quantitative decision analysis approach identifies a range for the optimal settlement amount in the claim process. Each party holds private information regarding its belief over the specifics of a claim. The specifics of a claim are classified into Liability, the likelihood of the defendant being found liable at a trial, and Damages, unanticipated expenditures plaintiff incurred due to the defendant’s alleged fault. A Bayesian Network model quantifies parties’ beliefs over Liability and Damages. This model represents parties’ legal arguments and their respective strengths and credibility. These beliefs become inputs to a non-cooperative game theory model. Non-cooperative game theory analyzes interactions between the claim parties at each stage of the claim. The asymmetric information game considers each party’s actions and strategy based on its belief over the expected outcome from litigation, and its belief over the opponent’s expected outcome from litigation. The analysis results in equilibriums that help parties decide how to resolve the claim and avoid costly and timely litigation. The resulting approach reveals predictive outcomes in construction claims using economic theory to analyze construction disputes

Antibacterial and self-cleaning properties of cotton fabric treated with TiO2/Pt

This study explores a new nanocomposite to produce a cotton fabric with superior self-cleaning and antibacterialproperties. The platinum loaded nano titanium dioxide (nanocomposite) has been synthesized through wet impregnationusing Pt precursor. The nanocomposite has been applied on cotton fabric and the fabric characteristics such as self-cleaningperformance, antibacterial and UV blocking activities are examined. Field emission scanning electron microscopy, energydispersiveX-ray spectroscopy and X-ray mapping are utilized to characterize the surface morphology and elementalanalysis of the treated cotton fabrics. The chemical composition of the nanocomposite has been investigated using X-rayphotoelectron spectroscopy and crystallinity of coatings by X-ray diffraction spectroscopy. Whiteness index, tensilestrength, flexibility and wettability of treated fabrics are also assessed. Results show that the photocatalytic self-cleaningperformance of the cotton treated with TiO2/Pt nanocomposite is superior to the cotton treated with nano-titanium dioxidealone. Also, adding platinum to nano-TiO2 shows the most promising antibacterial activities against both Staphylococcusaureus and Escherichia coli bacteria

Success and failure of endodontic treatment: predictability, complications, challenges and maintenance

The fundamentals of successful endodontic treatment are an awareness of the aetiology of the disease process and an understanding of factors that affect outcome. This paper aims to outline the prognostic factors found in the endodontic outcome literature to facilitate options appraisal and predictable treatment delivery. We will discuss pre-treatment, treatment and post-treatment factors. In summary, the significance of infection control throughout treatment, provision of an adequate coronal seal and appropriate restoration of the root-filled tooth are highlighted

Pozzolans' Effect on Durability of Light Concretes Made of LECA (Light Expanded Clay Aggregate) and Scoria in Corrosive Environments Containing Sulfuric acid

In the recent years numerous structures were made by using light concrete in their structures. The enhancement of resistance of light weight aggregates from one side, and weight loss of lightweight aggregates as well as the possibility of overproduction lead to an impressive increase in building structures by using light weight aggregates. In this research light weight concretes made of light weight aggregates of LECA and scoria containing the pozzolans of silica fume, Metakaolin, rice husk ash, poly propylene fibers with different percentages have been used and examined. After putting light weight concrete samples in acidic places containing sulfuric acid or PH=3, PH=5, PH=7 in the period of 180 days then the effect of this environment on the pushing resistance and the weight of these samples are analyzed. Results show that the concretes containing pozzolans have the better performance in comparison to the concretes which are produced without pozzolans and also the damage to light weighted aggregates concretes in acidic environments is more than regular concretes

Direct numerical simulation of the passive heat transfer in a turbulent flow with particle

Turbulent non-isothermal fully developed channel flow with solid particles was investigated through Direct Numerical Simulation combined with the point-particle approach. The focus was on the interactions between discrete and continuous phase and their effect on the velocity and the temperature of the particles. It has been found that low momentum inertia particles have a mean temperature similar to the fluid temperature and this effect is almost independent of particle thermal inertia. For particles with larger momentum, the inertia thermal effect is more complex, particle temperature in the near-wall and buffer region is significantly lower than the fluid temperature. The difference between the fluid mean temperature and particle mean temperature increases along with the momentum response time. This may have important consequences on the chemical reactions, technological processes and on the accuracy of temperature measurement techniques based on seeding particle

Thromboembolic Disease in Patients With Cancer and COVID-19: Risk Factors, Prevention and Practical Thromboprophylaxis Recommendations–State-of-the-Art.

Cancer and COVID-19 are both well-established risk factors predisposing to thrombosis. Both disease entities are correlated with increased incidence of venous thrombotic events through multifaceted pathogenic mechanisms involving the interaction of cancer cells or SARS-CoV2 on the one hand and the coagulation system and endothelial cells on the other hand. Thromboprophylaxis is recommended for hospitalized patients with active cancer and high-risk outpatients with cancer receiving anticancer treatment. Universal thromboprophylaxis with a high prophylactic dose of low molecular weight heparins (LMWH) or therapeutic dose in select patients, is currentlyindicated for hospitalized patients with COVID-19. Also, prophylactic anticoagulation is recommended for outpatients with COVID-19 at high risk for thrombosis or disease worsening. However, whether there is an additive risk of thrombosis when a patient with cancer is infected with SARS-CoV2 remains unclear In the current review, we summarize and critically discuss the literature regarding the epidemiology of thrombotic events in patients with cancer and concomitant COVID-19, the thrombotic risk assessment, and the recommendations on thromboprophylaxis for this subgroup of patients. Current data do not support an additive thrombotic risk for patients with cancer and COVID-19. Of note, patients with cancer have less access to intensive care unit care, a setting associated with high thrombotic risk. Based on current evidence, patients with cancer and COVID-19 should be assessed with well-established risk assessment models for medically ill patients and receive thromboprophylaxis, preferentially with LMWH, according to existing recommendations. Prospective trials on well-characterized populations do not exist

Systemic effects of periodontitis treatment in patients with type 2 diabetes: a 12 month, single-centre, investigator-masked, randomised trial

BACKGROUND: Chronic inflammation is believed to be a major mechanism underlying the pathophysiology of type 2 diabetes. Periodontitis is a cause of systemic inflammation. We aimed to assess the effects of periodontal treatment on glycaemic control in people with type 2 diabetes. METHODS: In this 12 month, single-centre, parallel-group, investigator-masked, randomised trial, we recruited patients with type 2 diabetes, moderate-to-severe periodontitis, and at least 15 teeth from four local hospitals and 15 medical or dental practices in the UK. We randomly assigned patients (1:1) using a computer-generated table to receive intensive periodontal treatment (IPT; whole mouth subgingival scaling, surgical periodontal therapy [if the participants showed good oral hygiene practice; otherwise dental cleaning again], and supportive periodontal therapy every 3 months until completion of the study) or control periodontal treatment (CPT; supra-gingival scaling and polishing at the same timepoints as in the IPT group). Treatment allocation included a process of minimisation in terms of diabetes onset, smoking status, sex, and periodontitis severity. Allocation to treatment was concealed in an opaque envelope and revealed to the clinician on the day of first treatment. With the exception of dental staff who performed the treatment and clinical examinations, all study investigators were masked to group allocation. The primary outcome was between-group difference in HbA1c at 12 months in the intention-to-treat population. This study is registered with the ISRCTN registry, number ISRCTN83229304. FINDINGS: Between Oct 1, 2008, and Oct 31, 2012, we randomly assigned 264 patients to IPT (n=133) or CPT (n=131), all of whom were included in the intention-to-treat population. At baseline, mean HbA1c was 8·1% (SD 1·7) in both groups. After 12 months, unadjusted mean HbA1c was 8·3% (SE 0·2) in the CPT group and 7·8% (0·2) in the IPT group; with adjustment for baseline HbA1c, age, sex, ethnicity, smoking status, duration of diabetes, and BMI, HbA1c was 0·6% (95% CI 0·3-0·9; p<0·0001) lower in the IPT group than in the CPT group. At least one adverse event was reported in 30 (23%) of 133 patients in the IPT group and 23 (18%) of 131 patients in the CPT group. Serious adverse events were reported in 11 (8%) patients in the IPT group, including one (1%) death, and 11 (8%) patients in the CPT group, including three (2%) deaths. INTERPRETATION: Compared with CPT, IPT reduced HbA1c in patients with type 2 diabetes and moderate-to-severe periodontitis after 12 months. These results suggest that routine oral health assessment and treatment of periodontitis could be important for effective management of type 2 diabetes. FUNDING: Diabetes UK and UK National Institute for Health Research.Diabetes UK and UK National Institute for Health Researc