Aerosol generating procedural risks and concomitant mitigation strategies in orthodontics amid COVID-19 pandemic - An updated evidence-based review

Effect of incorporating silica-hydroxyapatite-silver hybrid nanoparticles into the resin-modified glass ionomer on the adhesive remnant index score and shear bond strength of orthodontic metal brackets: An in vitro study

OBJECTIVES

This study aimed to assess the effect of addition of silica-hydroxyapatite-silver (Si-HA-Ag) hybrid nanoparticles to light-cure glass ionomer (GI) on shear bond strength (SBS) of metal brackets bonded with this adhesive and the adhesive remnant index (ARI) score.

MATERIAL AND METHODS

In this in vitro experimental study, 50 sound extracted premolars were assigned to 5 groups (n=10) for orthodontic metal bracket bonding with BracePaste® composite, Fuji ORTHO™ pure resin modified GI (RMGI), and RMGI reinforced with 2wt%, 5wt% and 10wt% Si-HA-Ag nanoparticles. The SBS of brackets was measured by a universal testing machine. Debonded specimens were inspected under a stereomicroscope at×10 magnification to determine the ARI score. Data were analyzed by one-way ANOVA, Scheffe test, Chi-square test, and Fisher's exact test (alpha=0.05).

RESULTS

The maximum mean SBS was recorded in BracePaste® composite followed by 2% RMGI, 0% RMGI, 5% RMGI and 10% RMGI. Only the difference between the BracePaste® composite and 10% RMGI was significant in this regard (P=0.006). The groups were not significantly different regarding the ARI scores (P=0.665). All the SBS values were within the clinically acceptable range.

CONCLUSION

Addition of 2wt% and 5wt% Si-HA-Ag hybrid nanoparticles to RMGI as orthodontic adhesive caused no significant change in SBS of orthodontic metal brackets while addition of 10wt% hybrid nanoparticles significantly decreased the SBS. Nonetheless, all the SBS values were within the clinically acceptable range. Addition of hybrid nanoparticles had no significant effect on the ARI score.

The Impact of COVID-19 on Dental Treatment in Kuwait—A Retrospective Analysis from the Nation’s Largest Hospital

Background: The COVID-19 pandemic has changed the way dentistry has been practiced the world over. This study sought to assess the impact of the COVID-19 pandemic on the patterns of attendance for dental treatment in a large hospital in Kuwait through comparisons with data from the year prior to the pandemic. Methods: A total of 176,690 appointment records from 34,250 patients presenting to the AlJahra specialist hospital in Kuwait for dental treatment from April 2019 to March 2021 were analyzed. The types of procedures and the departments in which they presented were analyzed, and the patterns of attendance before and during the pandemic were compared. Results: While there was a significant reduction in the number of orthodontic, endodontic, and periodontal procedures, there were no impacts on oral surgery, restorative procedures, or pediatric dentistry. Conclusions: There has been a return in the number of patients obtaining dental treatment; however, there has been a definite shift in the use of certain dental procedures.

Aerosol exposure of staff during dental treatments: a model study

Background

Due to exposure to potentially infectious aerosols during treatments, the dental personnel is considered being at high risk for aerosol transmitted diseases like COVID-19. The aim of this study was to evaluate aerosol exposure during different dental treatments as well as the efficacy of dental suction to reduce aerosol spreading.

Methods

Dental powder-jet (PJ; Air-Flow^®), a water-cooled dental handpiece with a diamond bur (HP) and water-cooled ultrasonic scaling (US) were used in a simulation head, mounted on a dental unit in various treatment settings. The influence of the use of a small saliva ejector (SE) and high-volume suction (HVS) was evaluated. As a proxy of aerosols, air-born particles (PM10) were detected using a Laser Spectrometer in 30 cm distance from the mouth. As control, background particle counts (BC) were measured before and after experiments.

Results

With only SE, integrated aerosol levels [median (Q25/Q75) µg/m³ s] for PJ [91,246 (58,213/118,386) µg/m³ s, p < 0.001, ANOVA] were significantly increased compared to BC [7243 (6501/8407) µg/m³ s], whilst HP [11,119 (7190/17,234) µg/m³ s, p > 0.05] and US [6558 (6002/7066) µg/m³ s; p > 0.05] did not increase aerosol levels significantly. The use of HVS significantly decreased aerosol exposure for PJ [37,170 (29,634/51,719) µg/m³ s; p < 0.01] and HP [5476 (5066/5638) µg/m³ s; p < 0.001] compared to SE only, even reaching lower particle counts than BC levels for HP usage (p < 0.001).

Conclusions

To reduce the exposure to potentially infectious aerosols, HVS should be used during aerosol-forming dental treatments.

Aerosol generating procedural risks and concomitant mitigation strategies in orthodontics amid COVID-19 pandemic - An updated evidence-based review

IMPORTANCE

The ongoing COVID-19 pandemic has posed unique challenges to orthodontic profession by adversely impacting provision of in-office orthodontic care due to prevailing uncertainty around risks pertaining to splatter and 'aerosol-generating procedures' (AGPs). This review aims to provide an insight into the prevailing and emerging evidence informing potential risks related to splatter and AGPs, and risk mitigation strategies employed for reducing the potential risk of SARS-CoV-2 transmission from dental bioaerosols.

METHODS

PubMed, Google Scholar, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, LILACS, WHO COVID-19 databases and preprint databases were searched for eligible English language publications. Citation chasing was undertaken up until the review date of 4 January 2021. Study selection, data extraction and risk of bias assessment was undertaken independently in duplicate, or else by consultation with a third author.

RESULTS

Following filter application and duplicates removed, a total of 13 articles assessing procedural mitigation measures were included. Seven included studies revealed overall low-risk of bias. The overall risk varied from unclear to high for rest of the studies, with the most concerning domains being blinding of the participants and the personnel and blinding of the outcome assessors. Accumulated consensual evidence points towards the use of dental suction devices with wide bore aspirating tips as effective procedural mitigation strategies. Variations in the literature can be observed concerning aerosol transmission associated with water spray use during debonding. Emerging direct evidence consistently supports adjunctive use of pre-procedural povidone-iodine mouthrinse to mitigate direct transmission risk in the orthodontic practice.

CONCLUSIONS

A thorough risk assessment concerning AGPs and implementation of consistent and evidence-based procedural mitigation strategies may play an indispensable role in navigating optimal orthodontic practice through unforeseen similar pandemic threats. High-quality robust research focussing on more biologically relevant models of dental bioaerosols in orthodontic settings is warranted.