Occlusion: is there a third way? A discussion paper.

This paper does not set out to describe the reasons why a new concept of dental care should be deemed as acceptable and recognised as mainstream. Rather, the starting point of this paper is the belief that some dentists who are increasing the overall vertical dimension for worn dentition patients are not using the protocols of the traditional 're-organised approach'. If adhesive direct restorations are used, there seems to be anecdotal indication that despite not restoring in the terminal hinge axis, it can have a successful outcome.So, while not criticising this approach simply because it does not follow orthodoxy, the paper has two objectives. It hopes to stimulate some debate and research on this subject. Furthermore, by suggesting some parameters for what might be considered a new approach, it aims to improve patient outcome.

SARS-CoV-2: characterisation and mitigation of risks associated with aerosol generating procedures in dental practices.

Introduction The objectives were to characterise the particle size distribution of aerosols generated by standard dental aerosol generating procedures (AGPs) and to assess the impact of aerosol-management interventions on 'fallow time'. Interventions included combinations of high-volume intraoral suction (HVS[IO]), high-volume extraoral suction (HVS[EO]) and an air cleaning system (ACS).Method A sequence of six AGPs were performed on a phantom head. Real-time aerosol measurements (particle size range 0.0062-9.6 µm) were acquired from six locations within a typical dental treatment room (35 m3).Results The majority (>99%) of AGP particles were <0.3 µm diameter and remained at elevated levels around the dental team during the AGPs. With no active aerosol-management interventions, AGP particles were estimated to remain above the baseline range for up to 30 minutes from the end of the sequence of procedures.Conclusions The results emphasise the importance of personal protection equipment, particularly respiratory protection. Use of HVS(IO), either alone or in combination with the ACS, reduced particle concentrations to baseline levels on completion of AGPs. These data indicate potential to eliminate fallow time. The study was performed using a phantom head so confirmatory studies with patients are required.

Students' perspectives of early and gradual transitioning between simulation and clinical training in dentistry and their suggestions for future course improvements.

INTRODUCTION: Students' perspectives on their learning environment are essential for course development and to enhance the educational experience. In dentistry, there is limited understanding of how students perceive their early clinical training. This study presents students' views on their gradual progression from simulation to patient care and describes the approaches they followed to adapt during this transitioning phase. METHODS: A qualitative study design was employed, drawing on focus group discussions conducted with students from the Division of Dentistry at the University of Manchester. The discussions were transcribed verbatim. Data collection and coding process followed the principles of thematic analysis and the inductive approach. FINDINGS: The sample was comprised of 28 undergraduate students, across four focus groups. Thematic analysis generated three key categories: students' immediate perspectives of early clinical training, students' approaches to adapting to the transitioning period and students' suggestions for future improvement. Further, subthemes emerged describing the positive gains which students recognised from their early and gradual clinical involvement and training. Despite experiencing stress and uncertainty, related to insufficient knowledge and immature multitasking skills in the early years of dental training, students were motivated by the clinical environment and identified several ways to adapt to it and enhance their learning. These included additional self-learning resources and simulation opportunities; inter-year group learning activities and further peer support and mentoring. CONCLUSION: The current study provided insights into students' experiences of learning through early clinical involvement and gradual transitioning between simulation and clinical environments in dentistry. The findings revealed that whilst students appreciated being involved in the clinic at an early stage, they had to adopt a variety of approaches to link their knowledge, learning and skills between the simulation and clinical environments. Students' suggested additional activities to link the learning gap between the two environments and to enrich their learning.

Fabrication of occlusal rims to record the maxillomandibular relation for complete dentures.

This article describes an alternative method to establish the inclination of the occlusal plane by using the hamular notch, incisive papilla plane. By using this plane, the fabrication of occlusal rims that conform to an ideal relationship may make chairside trimming of the rims more straightforward.

Fracture resistance of aluminium oxide and lithium disilicate-based crowns using different luting cements: an in vitro study.

AIM: The aim of this study was to investigate the fracture resistance of two types of ceramic crowns cemented with two different cements. METHODS AND MATERIALS: Forty premolar crowns were fabricated using lithium-disilicate (IPS Empress-2) and glass-infiltrated aluminium-oxide (In-Ceram) ceramic systems. The crowns were divided into four groups (n=10) with Group 1 (IPS Empress-2) and Group 2 (In-Ceram) cemented with glass ionomer cement. Group 3 (IPS Empress-2) and Group 4 (In-Ceram) were cemented with resin cement. Crowns were tested in a universal testing machine at a compressive-load speed of 10 mm/min. Fracture modes were grouped into five categories. One way analysis of variance (ANOVA) and Bonferroni post-hoc tests were used to detect statistical significances (p<0.05). RESULTS: The mean (SD) fracture resistance (Newtons) for Groups 1 to 4 were: 245.35 (82.69), 390.48 (67.03), 269.69 (10.33), and 418.36 (26.24). The cement type had no statistical significant effect (p>0.05) on fracture resistance within each ceramic system tested. In-Ceram crowns cemented with either glass ionomer or resin cements exhibited a statistically significantly higher fracture-resistance than IPS Empress-2 crowns (p<0.05). Minimal fracture in the test crowns was the common mode exhibited. CONCLUSION: Fracture resistance of IPS Empress-2 and In-Ceram crowns was not affected by the type of cement used for luting. CLINICAL SIGNIFICANCE: Both In-Ceram and IPS Empress-2 crowns can be successfully luted with the cements tested with In-Ceram exhibiting higher fracture resistance than IPS Empress-2.

Does the nature of the definitive impression material influence the outcome of (mandibular) complete dentures?

The effects of impression materials on the outcome of complete dentures are poorly understood. This double-blind cross-over randomized controlled trial investigated eleven adult edentulous patients. Each received a maxillary denture and three mandibular dentures (which differed only in the three materials used to record the definitive impressions). The three mandibular dentures were given in a random order. Patients' opinions of each denture were recorded using a Linear Analogue Scale. There was a statistically-significant difference between the outcome of the dentures constructed when zinc-oxide eugenol was used, this material being least favoured (p < 0.001). It would therefore appear that care should be exercised when selecting impression materials when constructing mandibular complete dentures.