A Comparative study on the Effectiveness of Augmented Reality on Denture Tooth Selection.

One of the most difficult aspects of providing removable dentures, for both the patient and the dentist, is the tooth selection process. The aim of this study was to assess the effectiveness of augmented reality (AR) on patient experience of the tooth selection process. MATERIALS AND METHODS: 3D scanning of upper anterior teeth of various shapes and sizes allowed for the creation of a virtual library that were subsequently used to programme an AR software application, 'ToothPick'. Seventeen participants were recruited to a comparative study at Leeds Dental Institute, over two clinical appointments, to trial the app and complete a 10-question survey to assess the efficacy of AR simulation. The sample size response generated outcome variables for 'perceived usefulness' and 'perceived ease of use' from the perspectives of the patient, dentist and technician. RESULTS: By the second appointment, 86% of participants preferred the app over the conventional methods for selection of denture teeth due to increased ease of use and accuracy that AR simulation had in replicating the wax try-in. CONCLUSION: The sample population favoured the adoption of AR technology to select denture teeth from the perspective of both the patient and the clinician.

Surveys of Current Teaching and Practice for Impressions for Complete Dentures.

OBJECTIVES: The 3 objectives are to assess current preferences for impressions for complete dentures, audit practice and compare practice to current UK teaching. METHODS: Three surveys where undertaken; a survey of GDPs preferences, an audit of practice and a survey of teaching in UK dental schools. RESULTS: UK Universities advocate border moulded custom trays. In stated preferences, 99% of practitioners used custom trays for private practice; 67% for NHS work. In actual use, the audit found 91% practitioners in private practice used custom trays; in NHS practice 78% did so. The most widely taught materials were silicone (43%), alginate (29%), & zinc oxide eugenol paste (19%). In practitioners stated preferences, 97% of NHS and 53% of private dentists listed alginate as an option; however the audit showed only 74% (NHS) and 52% (private) actually used alginate, with 20% (NHS) and 48% (private) using silicone. CONCLUSIONS: Definitive impressions in custom trays are used by GDPs for both private and NHS work; they are universally taught at UK dental schools. Alginate is popular in NHS practice; however, silicone is more widely taught in UK Universities. The use of silicone materials for definitive impressions has increased since 1999. In UK private practice silicone usage is aligned in popularity with alginate.

A Systematic Review and Meta-Analysis of Baseline Ohip-Edent Scores.

BACKGROUND: OHIP-EDENT is widely used in the literature to assess Oral-Health-Related-Quality-of-Life (OHRQoL) for edentulous patients. However the normal variance and mean of the baseline OHIP scores has not been reported. It would facilitate critical appraisal of studies if we had knowledge of the normal variation and mean of baseline OHIP-EDENT scores. An established figure for baseline OHIP-EDENT, obtained from a meta-analysis, would simplify comparisons of studies and quantify variations in initial OHRQoL of the trial participants. OBJECTIVES: The aim of this study is to quantify a normal baseline value for pre-operative OHIP-EDENT scores by a systematic review and meta-analysis of the available literature. METHODS: A systematic literature review was carried. 83 papers were identified that included OHIP-EDENT values. After screening and eligibility assessment, 7 papers were selected and included in the meta-analysis. RESULTS: A meta-analysis for the 7 papers by a random-effect model yielded a mean baseline OHIP-EDENT score of 28.63 with a 95% Confidence intervals from 21.93 to 35.34. CONCLUSION: A pre-operative baseline OHIP-EDENT has been established by meta-analysis of published papers. This will facilitate the comparison of the initial OHRQoL of one study population to that found elsewhere in the published literature.

A Randomised Controlled Trial of Postoperative Sensitivity after Class II Restoration with Bulk-Fill vs Conventional Composites.

INTRODUCTION: Bulk-fill composites may simplify posterior restorations, saving time and reducing technical complexity. Post-operative sensitivity is a risk of posterior composites; bulk-fill composites could mitigate this. This single centre, double-blinded, parallel groups randomised controlled trial compared postoperative sensitivity following restoration of class II carious lesions with bulk-fill or conventional, layered composite. NULL HYPOTHESIS: there will be no difference in post-operative sensitivity between the two materials. METHODS: Participants requiring class II restoration of posterior teeth were randomised to bulk-fill (FU) (Coltene Fill-UpTM) or conventional, layered (BE) (Coltene Brilliant Everglow) composite. Allocation was concealed during cavity preparation. Only the operating dentist knew allocation. The outcome was 24 h post-operative sensitivity. RESULTS: 41 patients were randomised (20/group). Two patients from FU group were excluded from analysis (factors unrelated to intervention). There was no difference in postoperative sensitivity at 24 h nor any time point. Only participant age and baseline sensitivity scores significantly impacted post-operative sensitivity. One restoration debonded in FU group at 10 days, with no other adverse effects. No difference in time taken to place restorations was seen. CONCLUSIONS: Within the study's limitations, post-operative sensitivity after class II posterior restorations was no different in bulk-fill restorations compared with conventional, incrementally cured composite.

Randomized Controlled Trial of Postoperative Sensitivity with Warm and Room Temperature Composite.

Physical properties of composite improve when it is preheated prior to polymerization. However, postoperative sensitivity may be considered a potential complication. A review of the literature revealed no reported randomized controlled trials (RCTs) of postoperative sensitivity when using preheated composite resin. The objective of the study was to determine if preheating composite leads to changes in postoperative sensitivity in a parallel RCT. In total, 120 eligible, consenting adults were recruited in private dental practice and randomized into 2 groups of 60 patients. One group had room temperature composite restorations placed and the second had composite preheated to 39°C. The primary outcome was sensitivity after 24 h by the visual analog scale (VAS), recorded blind by patients. Secondary outcomes were VAS scores recorded over a month. Blind statistical analysis used the Mann-Whitney U test to compare the 24-h VAS score between groups and repeated-measures analysis of variance to assess the change over time. Potential confounders were tested using regression models. A total of 115 patients completed the trial: 57 in the heated composite group and 58 in the room temperature group. Analysis of 24-h VAS scores found no statistically significant difference between the 2 groups ( P = 0.162). Examining the potential confounders confirmed the nonsignificant difference between heated and room temperature groups on the 24-h VAS score, after controlling teeth type and preoperative pulp test (effect size = 0.173, P = 0.317). Analysis of the secondary outcomes found significant changes (within-subject effect) in VAS scores over the review period ( F statistic = 4.7, P = 0.002) but not a significant (between-subject effect) difference between heated and room temperature groups over time (effect size = 0.102, P = 0.197). There was a significant correlation between preoperative VAS score and postoperative VAS score ( P < 0.001). For the restorations in this study, there was no detectable difference in postoperative VAS score between preheated and room temperature composite. Postoperative sensitivity decreased throughout the first month. Postoperative sensitivity was correlated to preoperative sensitivity (ISRCTN 76727312). Knowledge Transfer Statement: The results of this study can be used by clinicians when considering the advantages and disadvantages of preheated composite. The study found no evidence of any change in postoperative sensitivity when using preheated composite. Since preheated composite has superior physical properties, its use for routine care can be considered good practice.

Extraction forceps for small hands.

This paper discusses the problems encountered by small handed dentists when extracting teeth using standard forceps. An alteration in the design of standard upper forceps is proposed which will be advantageous to small handed dentists. The new design is 'open bladed', that is, when the handles are closed the blades are manufactured to be 5 mm apart.

A reattachment technique for fractured incisor tooth fragments: a case history and discussion of alternative techniques.

This paper describes the case history of a patient for whom two fractured central incisor fragments were reattached using an acid etch technique. The case demonstrates a method, which has not been reported previously, using pins to reinforce the attachment. Finally the case shows the failure of the reattachment on one central incisor and subsequent successful treatment by the use of a veneer crown.

Case report: the high proximal survey line.

This case report demonstrates a method of adding composite to a tooth to move a high survey line closer to the gingival margin. The purpose of this modification is to facilitate clasping.

Gender aesthetics in the natural dentition.

This paper questions whether the size, position and angulation of upper anterior teeth 'reflect' the gender of a patient. Forty-six casts of natural teeth were given to 11 experts. The experts were asked to assess the gender of the patients. Overall the intra-observer agreement was fair (kappa = 0.33). Inter-observer agreement was fair (kappa = 0.23). On average 55% of casts taken from men were classified as 'male' and 55% of the casts taken from women were classified as 'female'. It is concluded, on the basis of this study, experts can not distinguish gender by the visual assessment of upper anterior teeth on casts alone.

Cost-effectiveness of silicone and alginate impressions for complete dentures.

OBJECTIVE: The aim of this study was to assess the cost effectiveness of silicone and alginate impressions for complete dentures. METHODS: Cost effectiveness analyses were undertaken alongside a UK single centre, double blind, controlled, crossover clinical trial. Taking the perspective of the healthcare sector, effectiveness is measured using the EuroQol (EQ-5D-3L) which provides a single index value for health status that may be combined with time to produce quality adjusted life years (QALYs); and Oral Health Impact Profile (OHIP-EDENT). Incremental cost effectiveness ratios are presented representing the additional cost per one unit gained. RESULTS: Mean cost was higher in the silicone impression group (£388.57 vs. £363.18). Negligible between-group differences were observed in QALY gains; the silicone group had greater mean OHIP-EDENT gains. The additional cost using silicone was £3.41 per change of one point in the OHIP-EDENT. CONCLUSIONS: The silicone group was more costly, driven by the cost of materials. Changes in the EQ-5D and QALY gains over time and between arms were not statistically significant. Change in OHIP-EDENT score showed greater improvement in the silicone group and the difference between arms was statistically significant. Given negligible QALY gains and low level of resource use, results must be treated with caution. It is difficult to make robust claims about the comparative cost-effectiveness. CLINICAL SIGNIFICANCE: Silicone impressions for complete dentures improve patients' quality of life (OHIP-EDENT score). The extra cost of silicone impressions is £30 per patient. Dentists, patients and health care funders need to consider the clinical and financial value of silicone impressions. Different patients, different dentists, different health funders will have individual perceptions and judgements. ISRCTN01528038. NIHR-RfPB grant PB-PG-0408-16300. This article forms part of a project for which the author (TPH) won the Senior Clinical Unilever Hatton Award of the International Assocation for Dental Research, Capetown, South Africa, June 2014.

A randomised controlled trial of complete denture impression materials.

OBJECTIVES: There is continuing demand for non-implant prosthodontic treatment and yet there is a paucity of high quality Randomised Controlled Trial (RCT) evidence for best practice. The aim of this research was to provide evidence for best practice in prosthodontic impressions by comparing two impression materials in a double-blind, randomised, crossover, controlled, clinical trial. METHODS: Eighty-five patients were recruited, using published eligibility criteria, to the trial at Leeds Dental Institute, UK. Each patient received two sets of dentures; made using either alginate or silicone impressions. Randomisations determined the order of assessment and order of impressions. The primary outcome was patient blinded preference for unadjusted dentures. Secondary outcomes were patient preference for the adjusted dentures, rating of comfort, stability and chewing efficiency, experience of each impression, and an OHIP-EDENT questionnaire. RESULTS: Seventy-eight (91.8%) patients completed the primary assessment. 53(67.9%) patients preferred dentures made from silicone impressions while 14(17.9%) preferred alginate impressions. 4(5.1%) patients found both dentures equally satisfactory and 7 (9.0%) found both equally unsatisfactory. There was a 50% difference in preference rates (in favour of silicone) (95%CI 32.7-67.3%, p<0.0001). CONCLUSION: There is significant evidence that dentures made from silicone impressions were preferred by patients. CLINICAL SIGNIFICANCE: Given the strength of the clinical findings within this paper, dentists should consider choosing silicone rather than alginate as their material of choice for secondary impressions for complete dentures. TRIAL REGISTRATION: ISRCTN 01528038. This article forms part of a project for which the author (TPH) won the Senior Clinical Unilever Hatton Award of the International Assocation for Dental Research, Capetown, South Africa, June 2014.

A cross-over Randomised Controlled Trial of selective pressure impressions for lower complete dentures.

OBJECTIVES: The objective of the research was to assess patient preference for a selective pressure impression technique for complete dentures by means of a Randomised Controlled Clinical Trial (RCT). METHODS: A literature review revealed no reported RCT's of selective pressure impressions for complete dentures. A cross-over, randomised, controlled, clinical trial was performed comparing selective pressure impressions with a placebo and an alternative method of re-distributing pressure. A sample size calculation yielded 65 patients. Sixty-nine patients, who had a superficial mental foramen on the lower denture bearing area, were recruited for the study. The primary outcome was the patients' preference of the dentures provided. The hypothesis under investigation was that one of the dentures would be preferred by the patients. RESULTS: Sixty-six participants completed the trial, 33 (50%) preferred the denture from the selective pressure impression, 19 (29%) the denture with traditional pressure relief, and 14 (21%) the placebo control. 95% confidence intervals showed that the preference for the selective pressure impression was greater than that of the other two techniques. The null hypothesis was rejected. CONCLUSIONS: The participants in this trial showed a preference for the denture constructed from the selective pressure impression technique, providing dentists with useful evidence for a clinical impression technique.

Survey of prosthodontic impression procedures for complete dentures in general dental practice in the United Kingdom.

STATEMENT OF PROBLEM: Anecdotal evidence suggests impression techniques used in general dental practice may vary from those taught at dental schools. There is little published information on this topic. PURPOSE: This study identifies the materials and methods used by general dental practitioners for recording impressions for the provision of replacement of complete dentures. METHODS: A total of 905 questionnaires were sent to general dental practitioners in the Greater Manchester area to identify current clinical practices. RESULTS: The results revealed that 88% of respondents use only irreversible hydrocolloid for primary impressions. If multiple responses are included, 99% of respondents mentioned irreversible hydrocolloids as an option for primary impressions. In response to the same question for secondary impressions, 94% of respondents mentioned irreversible hydrocolloids as an option. Other material mentioned as an option for secondary impressions included zinc oxide-eugenol (29%) and polyvinyl siloxane (13%). With regard to special trays, 75% of respondents routinely used laboratory constructed special trays to take definitive impressions. Questions on the requisite spacing, perforation, handle design of special trays, and on disinfection showed a diversity of opinion among practitioners. CONCLUSIONS: Although this survey reflected a diverse range of clinical preferences, it is clear that irreversible hydrocolloid dominates the impression market for complete dentures. The use of special trays is normal practice for complete dentures in general dental practice in the United Kingdom.

T-cell prolymphocytic leukemia with helper-cell phenotype and a review of the literature.

The majority of published cases of prolymphocytic leukemia (PLL) have been of B-cell origin. Nineteen cases of PLL of T-cell type have been described, as has a single case of PLL having a surface phenotype with features of both B-cells and T-cells. This report presents a review of these cases and comparison with one case of T-cell PLL. By using specific monoclonal antibody technique, this case was subcategorized into helper-cell phenotype: E-rosette(+), SIG(-), Anti-T(+), Anti-B(-), Anti-monocyte(-), OKT3(+), OKT4(+), OKT6(-), OKT8(-), Ia(+), and Tdt(-). Cytochemical studies showed paranuclear acid phosphatase granules. Postmortem examination revealed a predominant T-cell zone infiltration by the leukemic cells in the spleen and lymph nodes, with involvement of multiple organs. The application of the monoclonal antibody technique, which can be standardized among different laboratories to subclassify lymphoproliferative disorders into functional subtypes, should lead to a better understanding and more effective treatment of this disease.

Effects ofp-chlorophenylalanine on the metabolism of serotonin from 5-hydroxytryptophan.

The effects ofD,L-ϱ-chlorophenylalanine methyl ester (PCPA-methyl ester) and two of its metabolites, 2-(ϱ-chlorophenyl)-ethylamine (PCPEA) and ϱ-chlorophenylacetic acid (PCPAA), on the metabolism of serotonin (5-HT) fromD,L-5-hydroxytryptophan (5-HTP) ware studied in vitro and in vivo using the telencephalon and brainstem of the rat. For in vivo studies and some in vitro experiments, rats were injected with either 100 mg/kg PCPA-methyl ester or saline alone on days 1, 2, and 3, and were killed on day 15. When the in vivo metabolism of 5-HT was to be studied, the saline group and the PCPA group of animals were injected with 75 µg/kg [(3)H]D,L-5-HTP 20 min before sacrificing. With respect to the values found for the saline-injected animals, the specific activity (S.A.; dpm/nmol) of 5-HIAA was significantly greater in the telencephanol and brainstem of the animals injected with PCPA-methyl ester. The S.A. of 5-HTP was the same in both groups; the S.A. of 5-HT was lower in the telencephalon of the PCPA group than in the saline group; in the brainstem, there was no difference. In both the saline- and PCPA-injected animals, the S.A. of 5-HIAA was greater than the S.A. of 5-HT. There was no difference between the saline- and PCPA-injected animals with regard to: (1)L-5-HTP decarboxylase activity; (2)L-5-HTP-induced release of [(3)H]5-HT in vitro from crude nerve ending fractions (P2); or (3) in vitro uptake of [(3)H]D,L-5-HTP and its conversion to [(3)H]5-HT using the P2 fraction. In vitro studies demonstrated that the PCPEA could directly cause a large increase in the release of [(3)H]5-HT from the P2 fraction, whereas PCPA and PCPAA had little or no apparent effect. The data were interpreted to suggest that in the telencephalon of the animals treated with PCPA-methyl ester, there was a higher turnover of 5-HT than was found in the saline-treated group.