Optical impressions assessment for overlay restorations with rubber dam: A clinical trial.

OBJECTIVE: The possibility of making impressions of teeth prepared with a rubber dam in place has been proposed; however, this requires trimming and rescanning the mesh, which has been described as a cause of accuracy loss. This study aims to clinically determine whether overlay restorations obtained from a scan with a rubber dam in place have equivalent marginal fit, contact points, and occlusal fit to the same type of restorations obtained from a scan without a rubber dam. MATERIAL AND METHODS: Thirty patients who underwent overlay restoration of a molar with at least one neighbouring tooth were selected. After tooth preparation, two scans were performed: one without a rubber dam and the other with a rubber dam. Restorations were randomly created from one scan or another. The marginal fit, interproximal contact points, and occlusal fit were evaluated clinically. Two meshes, with and without rubber dams, were also compared. RESULTS: No significant differences were observed in the clinical evaluation of the overlays made of the two meshes. The trueness of the mesh from the impression made with a rubber dam with respect to the mesh without a rubber dam was about 40 µm in the critical areas of the preparation (margins, intaglio, and interproximal contact points). CONCLUSIONS: The results of this study show that under the conditions performed and with the equipment used, there are no significant clinical differences between overlay restorations made from a scan with a rubber dam and those made from a scan without a rubber dam. CLINICAL SIGNIFICANCE: Scanning with a rubber dam in place may be a valid option for certain types of restorations under certain clinical conditions.

Interventions to reduce contaminated aerosols produced during dental procedures for preventing infectious diseases.

BACKGROUND: Many dental procedures produce aerosols (droplets, droplet nuclei and splatter) that harbour various pathogenic micro-organisms and may pose a risk for the spread of infections between dentist and patient. The COVID-19 pandemic has led to greater concern about this risk. OBJECTIVES: To assess the effectiveness of methods used during dental treatment procedures to minimize aerosol production and reduce or neutralize contamination in aerosols. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases on 17 September 2020: Cochrane Oral Health's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (in the Cochrane Library, 2020, Issue 8), MEDLINE Ovid (from 1946); Embase Ovid (from 1980); the WHO COVID-19 Global literature on coronavirus disease; the US National Institutes of Health Trials Registry (ClinicalTrials.gov); and the Cochrane COVID-19 Study Register. We placed no restrictions on the language or date of publication. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and controlled clinical trials (CCTs) on aerosol-generating procedures (AGPs) performed by dental healthcare providers that evaluated methods to reduce contaminated aerosols in dental clinics (excluding preprocedural mouthrinses). The primary outcomes were incidence of infection in dental staff or patients, and reduction in volume and level of contaminated aerosols in the operative environment. The secondary outcomes were cost, accessibility and feasibility. DATA COLLECTION AND ANALYSIS: Two review authors screened search results, extracted data from the included studies, assessed the risk of bias in the studies, and judged the certainty of the available evidence. We used mean differences (MDs) and 95% confidence intervals (CIs) as the effect estimate for continuous outcomes, and random-effects meta-analysis to combine data. We assessed heterogeneity. MAIN RESULTS: We included 16 studies with 425 participants aged 5 to 69 years. Eight studies had high risk of bias; eight had unclear risk of bias. No studies measured infection. All studies measured bacterial contamination using the surrogate outcome of colony-forming units (CFU). Two studies measured contamination per volume of air sampled at different distances from the patient's mouth, and 14 studies sampled particles on agar plates at specific distances from the patient's mouth. The results presented below should be interpreted with caution as the evidence is very low certainty due to heterogeneity, risk of bias, small sample sizes and wide confidence intervals. Moreover, we do not know the 'minimal clinically important difference' in CFU. High-volume evacuator Use of a high-volume evacuator (HVE) may reduce bacterial contamination in aerosols less than one foot (~ 30 cm) from a patient's mouth (MD -47.41, 95% CI -92.76 to -2.06; 3 RCTs, 122 participants (two studies had split-mouth design); very high heterogeneity I² = 95%), but not at longer distances (MD -1.00, -2.56 to 0.56; 1 RCT, 80 participants). One split-mouth RCT (six participants) found that HVE may not be more effective than conventional dental suction (saliva ejector or low-volume evacuator) at 40 cm (MD CFU -2.30, 95% CI -5.32 to 0.72) or 150 cm (MD -2.20, 95% CI -14.01 to 9.61). Dental isolation combination system One RCT (50 participants) found that there may be no difference in CFU between a combination system (Isolite) and a saliva ejector (low-volume evacuator) during AGPs (MD -0.31, 95% CI -0.82 to 0.20) or after AGPs (MD -0.35, -0.99 to 0.29). However, an 'n of 1' design study showed that the combination system may reduce CFU compared with rubber dam plus HVE (MD -125.20, 95% CI -174.02 to -76.38) or HVE (MD -109.30, 95% CI -153.01 to -65.59). Rubber dam One split-mouth RCT (10 participants) receiving dental treatment, found that there may be a reduction in CFU with rubber dam at one-metre (MD -16.20, 95% CI -19.36 to -13.04) and two-metre distance (MD -11.70, 95% CI -15.82 to -7.58). One RCT of 47 dental students found use of rubber dam may make no difference in CFU at the forehead (MD 0.98, 95% CI -0.73 to 2.70) and occipital region of the operator (MD 0.77, 95% CI -0.46 to 2.00). One split-mouth RCT (21 participants) found that rubber dam plus HVE may reduce CFU more than cotton roll plus HVE on the patient's chest (MD -251.00, 95% CI -267.95 to -234.05) and dental unit light (MD -12.70, 95% CI -12.85 to -12.55). Air cleaning systems One split-mouth CCT (two participants) used a local stand-alone air cleaning system (ACS), which may reduce aerosol contamination during cavity preparation (MD -66.70 CFU, 95% CI -120.15 to -13.25 per cubic metre) or ultrasonic scaling (MD -32.40, 95% CI - 51.55 to -13.25). Another CCT (50 participants) found that laminar flow in the dental clinic combined with a HEPA filter may reduce contamination approximately 76 cm from the floor (MD -483.56 CFU, 95% CI -550.02 to -417.10 per cubic feet per minute per patient) and 20 cm to 30 cm from the patient's mouth (MD -319.14 CFU, 95% CI - 385.60 to -252.68). Disinfectants ‒ antimicrobial coolants Two RCTs evaluated use of antimicrobial coolants during ultrasonic scaling. Compared with distilled water, coolant containing chlorhexidine (CHX), cinnamon extract coolant or povidone iodine may reduce CFU: CHX (MD -124.00, 95% CI -135.78 to -112.22; 20 participants), povidone iodine (MD -656.45, 95% CI -672.74 to -640.16; 40 participants), cinnamon (MD -644.55, 95% CI -668.70 to -620.40; 40 participants). CHX coolant may reduce CFU more than povidone iodine (MD -59.30, 95% CI -64.16 to -54.44; 20 participants), but not more than cinnamon extract (MD -11.90, 95% CI -35.88 to 12.08; 40 participants). AUTHORS' CONCLUSIONS: We found no studies that evaluated disease transmission via aerosols in a dental setting; and no evidence about viral contamination in aerosols. All of the included studies measured bacterial contamination using colony-forming units. There appeared to be some benefit from the interventions evaluated but the available evidence is very low certainty so we are unable to draw reliable conclusions. We did not find any studies on methods such as ventilation, ionization, ozonisation, UV light and fogging. Studies are needed that measure contamination in aerosols, size distribution of aerosols and infection transmission risk for respiratory diseases such as COVID-19 in dental patients and staff.

An Assessment of Direct Restorative Material Use in Posterior Teeth by American and Canadian Pediatric Dentists: II. Rubber Dam Isolation.

PURPOSE: The purpose of this study was to assess usage, indications, and contraindications for rubber dam isolation (RDI) by pediatric dentists in Canada and the United States. METHODS: A cross-sectional, web-based, self-administered survey was utilized to collect the opinions of all active pediatric dentist members of the Royal College of Dentists of Canada and the American Academy of Pediatric Dentistry on the use of direct restorative materials in posterior teeth (n equals 4,648; 19.3 percent response rate). The main survey also included a domain on the RDI utilization and its perceived indications and contraindications. Bivariate and multivariate analyses for RDI usage and its predictor were performed at two-tailed P<0.05. RESULTS: A response rate of 19.3 percent was obtained. Most participants (72.5 percent) reported using RDI "all the time." The material with the lowest usage of RDI was composite (82 percent) in the primary dentition and stainless steel crown (80.7 percent) in the permanent dentition. The three top-noted reasons for not using RDI included decreased trauma to the patient (66.2 percent), being able to prevent soft tissue from interfering without using RDI (55.9 percent), and decreased time for appointments (45.6 percent). CONCLUSION: Rubber dam isolation was valued by the majority of pediatric dentists when restoring primary and permanent dentition for all materials.

Cluster Effects in a National Dental PBRN restorative study.

Items in clusters, such as patients of the same clinician or teeth within the same patient, tend to be more similar than items from different groups. This within-group similarity, represented by the intraclass correlation coefficient (ICC), reduces precision, yielding less statistical power and wider confidence intervals, compared with non-clustered samples of the same size. This must be considered in the design of studies including clusters. We present ICC estimates from a study of 7,826 restorations placed in previously unrestored tooth surfaces of 4,672 patients by 222 clinicians in the National Dental Practice-Based Research Network, as a resource for sample size planning in restorative studies. Our findings suggest that magnitudes of ICCs in practice-based research can be substantial. These can have large effects on precision and the power to detect treatment effects. Generally, we found relatively large ICCs for characteristics that are influenced by clinician choice (e.g., 0.36 for rubber dam use). ICCs for outcomes within individual patients, such as tooth surfaces affected by a caries lesion, tended to be smaller (from 0.03 to 0.15), but were still sufficiently large to substantially affect statistical power. Clustering should be taken into account in the design of oral health studies and derivation of statistical power estimates for these studies (ClinicalTrials.gov, NCT00847470).

Rubber dam use during root canal treatment: findings from The Dental Practice-Based Research Network.

BACKGROUND: The Dental Practice-Based Research Network (DPBRN) provided a means to investigate whether certain procedures were performed routinely. The authors conducted a study to quantify rubber dam use during root canal treatment (RCT) among general dentists and to test the hypothesis that certain dentist or practice characteristics were associated with rubber dam use. METHODS: DPBRN practitioner-investigators (P-Is) answered a questionnaire that included items about rubber dam use and other forms of isolation during RCT. DPBRN enrollment questionnaire data provided information regarding practitioner and practice characteristics. RESULTS: A total of 729 (74 percent) of 991 P-Is responded; 524 were general dentists who reported providing at least some RCTs and reported the percentage of RCTs for which they used a rubber dam. Of these 524 P-Is, 44 percent used a rubber dam for all RCTs, 24 percent used it for 51 to 99 percent of RCTs, 17 percent used it for 1 to 50 percent of RCTs, and 15 percent never used it during RCT. Usage varied significantly by geographic region and practice type. The use of cotton rolls and other forms of isolation also was reported. CONCLUSIONS: Similar to other reports in the literature, not all DPBRN general dentists used a rubber dam during RCT. CLINICAL IMPLICATIONS: Because the clinical reference standard is to use a rubber dam during RCT, increasing its use may be important.

Rubber dam use during routine operative dentistry procedures: findings from the Dental PBRN.

Rubber dam use during operative dentistry procedures has been quantified based on questionnaires completed by dentists. However, based on the knowledge of the authors of the current study, there are no reports based on use during actual clinical procedures other than in dental materials studies and none based on routine care. The objectives of the current study were to: 1) quantify how commonly the rubber dam is used during operative dentistry procedures; 2) test the hypothesis that certain dentist, restoration and patient-level factors are associated with its use. A total of 229 dentist practitioner-investigators in The Dental Practice-Based Research Network (DPBRN) participated. DPBRN comprises five regions of the USA: Alabama/Mississippi, Florida/Georgia, Minnesota, Permanente Dental Associates and Scandinavia. Practitioner-investigators collected data on 9,890 consecutive restorations done in previously unrestored tooth surfaces from 5,810 patients. Most dentists (63%) did not use a rubber dam for any restoration in this study. A rubber dam was used for only 12% of restorations, 83% of which were used in one DPBRN region. With regions accounted for, no other dentist characteristics were significant. A multi-level multiple logistic regression of rubber dam use was done with restoration and patient-level variables modeled simultaneously. In this multi-variable context, these restoration-level characteristics were statistically significant: tooth-arch type, restoration classification and reason for placing the restoration. These patient-level characteristics were statistically significant: ethnicity, dental insurance and age. These results, obtained from actual clinical procedures rather than questionnaires, document a low prevalence of usage of the rubber dam during operative dentistry procedures. Usage varied with certain dentist, restoration and patient-level characteristics.

Rubber dam use among a subpopulation of Nigerian dentists.

In this cross-sectional questionnaire-based study, we surveyed the attitudes toward, knowledge of, and use of rubber dams (RDs) among dentists in southern Nigeria. The questionnaire, which was distributed and collected by one of the authors, requested information on the dentists' background characteristics, attitudes, and knowledge. Data were analyzed with SPSS, and the chi-square was used to assess differences in categorical variables. A total of 100 out of 108 dentists responded (92.6% response rate). The prevalence of RD use was 18%. Dentists in the government sector used RDs more often than did dentists in the private sector. About 77% of dentists had not used RDs or were unaware of how to use them. All specialists had seen RDs, but only 56% had used one in their practice. All dentists believed in the effectiveness of RDs. We conclude that rubber dams are underutilized in this population, and that dentists need to be made aware of the possibility of rubber dam use through an awareness campaign.

Improving clinical assessment: evaluating students' ability to identify and apply clinical criteria.

AIM: There is ongoing concern by health educators over the inability of professionals to accurately self-assess their clinical behaviour and standards, resulting in doubts over a key expectation of effective self-regulation in the health professions. Participation by students in the assessment process has been shown to increase the understanding of assessment criteria in written assessment tasks. How this might transfer to the clinical setting is the focus of this study. This paper is part of an ongoing investigation of the impact on learning of a series of activities that provides students with opportunities to discuss and apply criteria and standards associated with self-assessment in clinical dentistry. Our aim was to evaluate whether participation in these assessment activities improved the ability of first-year dental students to recognise behaviours demonstrated by 'peers' in videos of clinical scenarios and to relate these to the assessment criteria. MATERIALS AND METHODS: A series of three workshops in conjunction with weekly clinical assessment activities in Semesters 1 and 2 were use to support first-year students' learning of clinical assessment criteria. The design of the workshops was based on the principles of social constructivist theories of learning and the concept of tacit knowledge. Accordingly workshop activities were planned around videos that were specifically constructed to illustrate procedures and behaviours typical of those observed by staff and tutors in the first year of the dental course at The University of Adelaide, Australia. First-year students viewed the videos prior to and after the workshops and recorded observed behaviours that related to the assessment criteria that were used in their clinical practice course. Student learning outcomes were assessed 10-14 weeks after the initial workshop and again up to 42 weeks later. To check whether learning resulted from repeated viewing of the videos without formal discussion, a reference group of third-year students who did not attend the workshops also viewed the videos two times, separated by 12 weeks, and recorded observations in the same way. RESULTS: There was no consistent evidence that repeat viewing of the videos in isolation resulted in improved recognition of 'peer' behaviours by third-year dental students. Results for the first-year students indicated that the workshops and clinical assessment activities had a significantly positive effect on the ability of students to identify 'peer' behaviours related to the criteria used for clinical assessment. In particular, students' recognition in others of knowledge and professional behaviours improved significantly. This improvement was retained over the year and students were able to recognise these behaviours in other scenarios relevant to their year level. CONCLUSIONS: This early exposure to the process of clinical assessment, coupled with ongoing self-assessment and tutor feedback throughout first year, improved the ability of first-year students to identify and apply some key assessment criteria to observed 'peer' behaviour, and this ability was retained over time.

Teaching of direct posterior resin composite restorations in UK dental therapy training programmes.

AIM: With the numbers of dental therapists involved in the delivery of dental care within the UK on the increase, and the trend towards the use of direct resin composites (composites) for the restoration of posterior teeth, this study was undertaken to describe the teaching of posterior composites in dental therapy training programmes in the UK. A secondary aim was to identify differences in techniques for posterior composites taught within these dental therapy training programmes. METHODS: In 2008/9, a questionnaire seeking information on the teaching of posterior composites was distributed by email to 13 centres with dental therapy training programmes in the UK. This questionnaire sought information relating to the teaching of direct posterior composites to dental therapy students, including the amounts of preclinical and clinical teaching in respect of deciduous and permanent teeth, numbers of restorations placed, contraindications to placement, and details in respect of operative techniques. RESULTS: Ten completed responses were received (response rate = 77%). In ten programmes, student dental therapists received clinical training in the placement of composite restorations in the occlusal surfaces of premolar and permanent molar teeth, and nine programmes included such training for two and three surface occlusoproximal restorations. The mean proportions of posterior restorations placed clinically by the trainee dental therapists in permanent teeth using dental amalgam and composite were 52% and 46% respectively (range: amalgam = 20-95%; composite = 5-70%). CONCLUSION: With the exception of one programme, the teaching of posterior composites is a well established element of dental therapy training. Some variations were noted in the teaching of clinical techniques between respondent training centres. It is suggested that to ensure harmony in approaches to treatments provided by graduated therapists that training centres look to relevant consensus documents, such as those of the British Association for the Teaching of Conservative Dentistry. The findings of our study are important for the future provision of oral healthcare, given the growing evidence base in favour of minimally invasive dentistry.

A comparison of paediatric dentists' and general dental practitioners' care patterns in paediatric dental care.

AIM: The aim of this study was to compare the care patterns of paediatric dentists and general dentists in the dental treatment of children in the Netherlands. STUDY DESIGN AND METHODS: A case control study was completed based on the financial records of one of the largest Dutch health insurance companies. After medical ethical approval the dental records from 2004, 2005 and 2006 of 16 paediatric dentists were used and compared with the records of general practitioners with the same number of insured paediatric patients from the same age and urbanisation level. Preventive, diagnostic and restorative care for four consecutive age groups (<6, 6-8, 9-11, 12-17 yrs) were used as independent variables. Differences between the dentists and the age groups were tested with the Independent-Sample t-Test and ratios were calculated. RESULTS: Compared with general dentists, paediatric dentists use statistically significant more often rubber-dam (p=0.009) and did more preventive treatments (p<0.001) in children up to aged 11 yrs, more extractions (p<0.001), took more radiographs (p=0.027) and used local analgesia more often (p=0.002) in children until aged 8 yrs and performed more restorations (p=0.02) in children up to 6 yrs of age. There was no significant difference in the care pattern of the dentists for the oldest age group (12-17 yrs). The care-index for paediatric dentists and general dentists from this research was comparable with Dutch epidemiological studies. CONCLUSION: Compared with general dentists, paediatric dentists have a more extensive treatment approach when treating children. In the youngest age groups the differences are the most pronounced. Further studies are needed to clarify whether the cause is the needs of the patient or an attitude of supervised neglect by the general dentists.

Trends in dental education in the Persian Gulf--an example from Iran: contemporary placement of posterior composites.

In recent years, there has been expansion of dental education programmes from established European and North American schools into regions in the Middle East, the Persian Gulf States, and Asia. Accompanying this, there has been migration of dentists from these regions of the world to Europe and North America in the hope of finding employment or to pursue postgraduate education. Little awareness exists, however in western countries on the amount and level of clinical training provided in dental schools in which these dentists have trained. The aim of this paper is to investigate the teaching to undergraduate students in Iran of an important aspect of clinical dentistry which is showing continual development in western schools, namely the use of resin-based composites in the restoration of posterior teeth. In 2008, a questionnaire seeking information on the teaching of posterior resin-based composites was distributed by email to the person responsible for delivering teaching of operative dentistry in each of the 18 dental schools with undergraduate dental degree programmes in Iran. All 18 schools teach the placement of occlusal and occlusoproximal resin-based composite restorations in premolar and permanent molar teeth. Resin-based composites currently account for 42% of posterior direct restorations placed by undergraduates in Iran. Despite variations between dental schools being noted in the teaching of certain techniques for posterior resin-based composites, the overall extent and content of teaching of posterior resin-based composites in Iran could be described as comparable to that observed in western countries.

Clinical assessment of postoperative sensitivity in posterior composite restorations.

This incidence of postoperative sensitivity was evaluated in resin-based posterior restorations. Two hundred and ninety-two direct restorations were evaluated in premolars and molars. A total of 143 Class I and 149 Class II restorations (MO/OD and MOD) were placed in patients ranging in age from 30 to 50 years. After the cavity preparations were completed, a rubber dam was placed, and the preparations were restored using a total-etch system (Prime & Bond NT) and a resin-based restorative material (TPH Spectrum). The patients were contacted after 24 hours and 7, 30 and 90 days postoperatively and questioned regarding the presence of sensitivity and the stimuli that triggered that sensitivity. The Chi-square and Fisher's Exact Test were used for statistical analysis. Evaluation at 24 hours after restorative treatment revealed statistically significant differences among the types of cavity preparations restored and the occurrence of postoperative sensitivity (p = 0.0003), with a higher frequency of sensitivity in Class II MOD restorations (26%), followed by Class II MO/DO (15%) and Class I restorations (5%). At 7, 30 and 90 days after restorative treatment, there was a decrease in the occurrence of sensitivity for all groups. The percentage of sensitivity among the groups was not significantly different. This study shows that the occurrence of sensitivity is correlated with the complexity of the restoration.

An assessment of rubber dam usage amongst specialists in paediatric dentistry practising within the UK.

OBJECTIVE: Rubber dam is recommended by the British Society of Paediatric Dentistry (BSPD) for various restorative and endodontic procedures. To date, there has been no report of actual usage of rubber dam within the speciality of paediatric dentistry. The aim of this study was to assess the usage of rubber dam amongst paediatric dentistry specialists within the UK. METHODS: A postal questionnaire was distributed to all practitioners registered on the UK General Dental Council's 2004 specialist list in paediatric dentistry. RESULTS: Data were available for 162 questionnaires (a 75% response rate), and of these, 85% of respondents worked in the National Health Service (NHS), 4% were private practitioners and the remainder had a mixed NHS/private practice. Regarding the benefits of rubber dam, 65% and 52% of respondents quoted patient safety and moisture control, respectively. Perceived difficulties of dam usage were lack of patient cooperation and the non-necessity for a particular treatment, as quoted in 64% and 36% of the completed questionnaires, respectively. The most common modes of isolation for anterior and posterior teeth were Dry Dam(R) (58%), and clamp and dam (80%), respectively. CONCLUSION: Current BSPD guidelines recommend rubber dam usage for many restorative procedures; however, it would appear that there is wide variability in the application, as well as under-use, of rubber dam.

The microscope and endodontics.

The incorporation of the microscope in clinical endodontics has had profound effects on the way endodontics is done and has changed the field fundamentally. This article outlines the key prerequisites for the use of the microscope in nonsurgical endodontic procedures, discusses which procedures benefit from using the microscope, and addresses the issue of cost versus patient benefit.

Root canal retreatment: I. Case assessment and treatment planning.

Root canal retreatment is often the preferred method of treating a tooth in which root canal treatment has failed. Part one of this two-part article discusses reasons for failure of root canal treatment, case assessment and treatment planning. Part two describes some of the practical techniques that are available to the practitioner and the rationale for root canal retreatment.

A cost-effective simulation curriculum for preclinical endodontics.

A challenge in contemporary dental education is to achieve a smooth transition from preclinical teaching environments to patient-care clinics in a cost-effective manner. The preclinical endodontic courses at The University of Texas, Dental Branch at Houston provide a unique learning environment that enables the student to perform endodontic treatment on extracted teeth in a typodont, and be involved in diagnosis and treatment-planning discussions. The specially designed stone typodont used has built-in radiographic capability, and is mounted at each chair in the clinic. During each preclinical session, students are assigned clinical cubicles and proper aseptic protocol is followed. Students are required to wear gloves, masks and eyewear, and place a rubber dam during treatment. Written self-assessment evaluations based upon prescribed criteria are utilised; feedback is given by faculty composed of both full-time endodontists and graduate students who periodically rotate and are calibrated on a regular basis. In the lecture phase, clinical case scenarios are presented to reinforce concepts of diagnosis and emergency care and to help integrate endodontics with other disciplines; a Socratic-like teaching style is established by the faculty facilitator to create an environment for developing critical-thinking and problem-solving skills. The overall feedback from graduating students has been very positive. Advantages of this format are an easier transition to patient management, a more keen interest in specialsation and a perceived increase in levels of confidence.