Managing dental caries against the backdrop of COVID-19: approaches to reduce aerosol generation

BDJ Minimum Intervention Dentistry Themed Issue CLINICAL Managing dental caries against the backdrop of COVID-19: approaches to reduce aerosol generation Ece Eden,*1 Jo Frencken,2 Sherry Gao,3 Jeremy A. Horst4,5 and Nicola Innes6 Key points Uncertainty and the emerging evidence that SARS-CoV-2 may be transmitted via airborne routes has implications for practising dental procedures that generate aerosols. There are evidence-based treatments including use of high-viscosity glass-ionomer sealants, atraumatic restorative treatment, silver diamine fluoride, the Hall Technique and resin infiltration, which remove or reduce aerosol generation during the management of carious lesions. This risk reduction approach for aerosol generation may guide practitioners to overcome the less favourable outcomes associated with temporary solutions or extraction-only approaches in caries management. Abstract The COVID-19 pandemic resulted in severe limitation and closure of dental practices in many countries. Outside of the acute (peak) phases of the disease, dentistry has begun to be practised again. However, there is emerging evidence that SARS-CoV-2 can be transmitted via airborne routes, carrying implications for dental procedures that produce aerosol. At the time of writing, additional precautions are required when a procedure considered to generate aerosol is undertaken. This paper aims to present evidence-based treatments that remove or reduce the generation of aerosols during the management of carious lesions. It maps aerosol generating procedures (AGPs), where possible, to alternative non-AGPs or low AGPs. This risk reduction approach overcomes the less favourable outcomes associated with temporary solutions or extraction-only approaches. Even if this risk reduction approach for aerosol generation becomes unnecessary in the future, these procedures are not only suitable but desirable for use as part of general dental care post-COVID-19. Background The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has precipitated the COVID-19 pandemic. The World Health Organisation (WHO) 1 has recommended a society-wide quarantine approach (during acute or peak phases of the disease), social distancing and handwashing followed by contact tracing. Alongside this, most countries have suspended elective and non-urgent dental care,2,3 closing many practices with only emergency treatment Ege University, School of Dentistry, Department of Paediatric Dentistry, Bornova, Izmir, 35100, Turkey; 2 Radboud University, Department of Oral Function and Prosthetic Dentistry, College of Dental Sciences, Radboud University Medical Centre, Nijmegen, 6525 GA, The Netherlands; 3Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong; 4Director of Clinical Innovation, DentaQuest, Boston, MA 02129 USA; 5University of Washington, Department of Oral Health Sciences, Seattle, 98195, USA; 6 Professor and Honorary Consultant, Paediatric Dentistry, School of Dentistry, College of Biomedical & Life Sciences, Cardiff University, Heath Park, Cardiff, CF14 4XY, UK. *Correspondence to: Ece Eden Email address: 1 Refereed Paper. Accepted 7 August 2020 https://doi.org/10.1038/s41415-020-2153-y provision.4,5,6 This acute phase of the pandemic is subsiding, although further acute phases are being seen in different countries. There is increasing dental need across populations and dental practices are suffering financially, so practices are opening and commencing care. However, the WHO has taken a cautious and risk assessment approach and recommended that situations where aerosol generating procedures (AGPs) are carried out should be reduced to a minimum, with additional precautions in place. It is still controversial but there is growing concern over possible airborne transmission of SARS-CoV-2.4,5,6,7 Although there has been much written about possible spread of COVID-19 through aerosols generated in the dental surgery, reviews of the evidence show there is little directly relating to respiratory viruses, despite over 70 years of research into bio-aerosols in dental settings.8,9,10,11 Studies of microbial content of aerosols and splatter generated during dental procedures have mostly involved aerobic bacteria.9,10,11,12,13,14,15 Viral studies are sparse, focusing on blood-borne HIV and hepatitis B.8,16 This limits confidence in the assumptions around transmission of SARSCoV-2 during dental treatment. Although there seems to be little supporting evidence for mass transmission of respiratory pathogens through provision of dental care in the past, evidence is still emerging around transmission of this novel virus, where there is no innate immunity in the global population. In general, management of dental caries has traditionally involved using instruments that have potential to generate bio-aerosols containing saliva, blood and tooth debris; the high-speed air rotor,17,18,19,20,21 slow-speed handpiece22,23,24 and use of the air-water syringe to complete steps for most dental materials.16,17,25,26 Until uncertainty around the level of risk associated with SARS-CoV-2 transmission between dental staff and patients is resolved or an acceptable level of risk is agreed, and because many aspects of dental treatment generate aerosols, a precautionary position is to keep aerosol generation as low as possible. Aim This paper presents evidence-based management for dental caries that removes or reduces the generation of aerosols and aids personalised care planning based around AGP reduction. BRITISH DENTAL JOURNAL | VOLUME 229 NO. 7 | October 9 2020 © The Author(s), under exclusive licence to British Dental Association 2020 411 CLINICAL Table 1 Direct restorative procedures (ie not involving a laboratory stage) for managing coronal and root surface carious lesions for permanent and primary teeth with high, low and non-AGP alternatives Lesion location High AGP* Low AGP* Non-AGP Carious lesions limited to enamel Smooth surface N/A Resin infiltration Maximise fluoride during tooth brushing Topical fluoride therapy (Other remineralisation agents**) Occlusal surface N/A Resin fissure sealant ART/HVGIC sealant GIC sealant Approximal surface N/A Resin infiltration Fluoride (Other remineralisation agents**) Carious lesion extending into dentine or on root surface Smooth or root surface Carious tissue removal (high-speed air rotor) and composite resin restoration N/A ART restoration NRCC SDF Occlusal surface Carious tissue removal (high-speed air rotor) and composite resin restoration Resin fissure sealant (minimal enamel breakdown) ART restoration NRCC† SDF Approximal/multi-surface Carious tissue removal (high-speed air rotor) and composite resin restoration Stainless steel crown (conventional placement) Zirconia crown Resin infiltration (outer 1/3 dentine) ART restoration† Hall Technique NRCC† SDF† Key: * = use rubber dam with (...truncated)