Remote clinical consultations in restorative dentistry

Specialist consultations are routine in medical and oral healthcare provision. These take place as an 'in-person' event in the secondary care centres. The primary outcome of the specialist consultation is to provide the dentist and the patient with a specialist assessment, diagnosis, prognosis and a proposed care plan. This in-person procedure remains the gold-standard as it is a considered safe and effective. It presents a number of shortcomings: (1) The referring clinician is not actively involved in the decision-making process. (2) The patient must travel to the secondary care centre for the consultation, creating inequalities of care provision. (3) The patient travel has a carbon footprint. (4) The setting of the referral centre can be unfamiliar and intimidating to the patient. (5) The outbreak of COVID-19 highlighted the need for alternative system to address this need. This clinical study assessed the feasibility and effectiveness of undertaking remote clinical consultations in restorative dentistry between a patient and dentist co-located in a clinical primary care dental practice and a specialist consultant in a remote secondary care centre. Method: A remote clinical consultation in restorative dentistry was conducted that enabled full engagement between the remote consultant and the patient/General Dental Practitioner (GDP) in the dental surgery. A comprehensive bespoke high-speed secure internet connected hardware and software platform was used. Each participant completed a semi-structured interview and a validated questionnaire covering four domains: Patient safety, communication between different parties, formulation of a treatment plan, and effectiveness of the technology. Results: Effective and safe clinical consultations were carried out in all the cases, regardless of gender, age and presenting complaint. Neither the process nor the outcomes were inferior to an in-person consultation. Conclusion: This pilot in-practice clinical effectiveness study identified that Remote Clinical Consultations (RCCs), as conducted in this study, are effective for the delivery of specialist consultations in restorative dentistry. They are not inferior to an in-person consultation. Secondary outcomes: Three-way discussion was very positive; high levels of acceptability from the patients and the referring GDPs; an alternative to patient travel, reducing travel inconvenience, cost and the environmental burden from the associated carbon dioxide emissions

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

The global burden of cancer attributable to risk factors, 2010–19: a systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND: Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. METHODS: The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk–outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. FINDINGS: Globally, in 2019, the risk factors included in this analysis accounted for 4·45 million (95% uncertainty interval 4·01–4·94) deaths and 105 million (95·0–116) DALYs for both sexes combined, representing 44·4% (41·3–48·4) of all cancer deaths and 42·0% (39·1–45·6) of all DALYs. There were 2·88 million (2·60–3·18) risk-attributable cancer deaths in males (50·6% [47·8–54·1] of all male cancer deaths) and 1·58 million (1·36–1·84) risk-attributable cancer deaths in females (36·3% [32·5–41·3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20·4% (12·6–28·4) and DALYs by 16·8% (8·8–25·0), with the greatest percentage increase in metabolic risks (34·7% [27·9–42·8] and 33·3% [25·8–42·0]). INTERPRETATION: The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden

Three-dimensional finite element analysis of stress distribution in a tooth restored with full coverage machined polymer crown

The effect of a restored machined hybrid dental ceramic crown–tooth complex is not well understood. This study was conducted to determine the effect of the stress state of the machined hybrid dental ceramic crown using three-dimensional finite element analysis. Human premolars were prepared to receive full coverage crowns and restored with machined hybrid dental ceramic crowns using the resin cement. Then, the teeth were digitized using micro-computed tomography and the teeth were scanned with an optical intraoral scanner using an intraoral scanner. Three-dimensional digital models were generated using an interactive image processing software for the restored tooth complex. The generated models were imported into a finite element analysis software with all degrees of freedom concentrated on the outer surface of the root of the crown–tooth complex. To simulate average occlusal load subjected on a premolar a total load of 300 N was applied, 150 N at a buccal incline of the palatal cusp, and palatal incline of the buccal cusp. The von Mises stresses were calculated for the crown–tooth complex under simulated load application was determined. Three-dimensional finite element analysis showed that the stress distribution was more in the dentine and least in the cement. For the cement layer, the stresses were more concentrated on the buccal cusp tip. In dentine, stress was more on the cusp tips and coronal 1/3 of the root surface. The conventional crown preparation is a suitable option for machined polymer crowns with less stress distribution within the crown–tooth complex and can be a good aesthetic replacement in the posterior region. Enamic crowns are a good viable option in the posterior region

The effect of crown fabrication process on the fatigue life of the tooth-crown structure

Objective To compare the fatigue strength of lithium disilicate ceramic crowns when cemented as a compound structure, as a function of the manufacturing process and the type of ceramic variation. Method A typodont maxillary first premolar was prepared for an all-ceramic crown in accordance with the manufacturer's guidelines for monolithic ceramic crowns (IPS e. max®; Ivoclar-Vivadent, Liechtenstein). 60 dies were duplicated in a polymer with a Young's Modulus closely matched to dentine (Alpha die, Schütz GmbH). Three different crown fabrication techniques were used (n = 20): (i) Manually applied wax spacer and pressed-crown; (ii) digitally scanned preparation, CAD-printed wax-pattern (D76PLUS, Solidscape Inc.) and pressed-crown; (iii) digitally scanned preparation and machined-crown (CEREC-inLab® v3.6 Sirona GmbH). Resin-based cement (Variolink-II®, Ivoclar-Vivadent, Liechtenstein) was employed with a standardised mechanised cementation technique to apply a controlled axial cementation pressure [Universal testing machine (Lloyd LRX®, Lloyd Materials Testing Inc)]. The samples were subjected to fatigue life testing with a cyclic impact load of 453 N for 1.25 × 106cycles at 37C⁰ and 1 Hz frequency until the point of fracture. Result There was a significant difference in the resistance to fatigue loading between the three groups. Weibull probability analysis and the α and β Weibull parameters indicate that the teeth restored with a ‘Manually-applied wax spacer and pressed-crown’ are best able to resist cyclic fatigue loading. They also have the most uniform interface geometry. Conclusion Teeth restored with IPS e. max® crowns constructed by manually applied wax spacer and pressing, have a more uniform interface and a greater structural integrity than wax CAD-printed patterns or CAD-CAM crowns

Evaluation of the stress pattern in the resin-based composite restoration of an endodontically treated premolar tooth : a finite element analysis study

This study aimed to assess the stress values in an endodontically treated maxillary premolar restored with a direct placement of adhesive composite restoration. An ortho-grade root-treatment was performed on a single-rooted maxillary premolar. Three types of cavities were prepared as follow: (1) O: Occlusal access cavity (one surface), (2): MO: access cavity with mesial extension equal to one third of bucco-palatal cusp width and 1 mm above the cementoenamel junction (two surfaces), (3) MOD: access cavity with mesial and distal extensions equal to one third of buccopalatal cusp width and 1 mm above the cementoenamel junction (three surfaces). After each restorative procedure, the restored-tooth complex was scanned using a micro-computed tomography scanner. A three-dimensional (3D) structure for each individual layer, including the enamel, dentine, composite restoration, and the gutta-percha of the restored tooth complex, was generated with interactive medical image processing software, whereas the biomechanical behavior and stress pattern distribution were evaluated using a finite element analysis software programme. The results revealed that the MO-restored tooth complex showed lower stress values than the onesurface (O) and three-surface (MOD) restored cavities. The generated stress values in the twosurface (MO) restored cavity in the present study were less than that of the one-surface (O) or three-surface (MOD) restored cavities. It can be concluded that, by increasing the C-factor, higher stress values are more likely to occur in the restored tooth. Greater stress values were observed in endodontically treated tooth with MOD restoration, which might have negative consequences on the fracture strength of the whole structure