Digital versus analogue impression taking – which one is the safest in a post-COVID-19 world?

digital impression taking with 3shapeWith COVID-19 changing the way many practise dentistry, 3shape questions whether digital impression taking is safer than analogue.

In a hygiene and safety-conscious industry, COVID-19 has pushed the subject even higher up the agenda. Consequently, what does independent research tell us about digital and analogue impression taking and dental hygiene and safety?

1. With analogue impressions your workflow needs extra steps

Traditional impression techniques require handling multiple items. Including the tray, chewing waxes, impression materials and also any associated appliances. These handling factors are however, eliminated with digital impressions (Barenghi et al, 2019).

Conventional impressions/casts that are transferred to a lab involve transportation, which also increases the risk of cross-infection (Sofou et al, 2002; Vazquez-Rodrıguez et al, 2018). They can involve many hours in potentially humid conditions. Digital impressions with Trios do not require any physical transportation from clinic to the lab.

2. Conventional impressions are challenging to disinfect. Digital scans require no disinfection

A wide variety of chemical solutions and techniques are recommended to disinfect impression materials (Mushtaq and Khan, 2018; Chidambaranathan and Balasubramanium, 2019).

Getting the Trios ready for use includes thorough cleaning and disinfection between patients. This also includes a strict protocol to clean and disinfect the scanner body and autoclaving the scanner tips. It therefore ensures proper disinfection between uses.

3. Conventional impression and cast handling between lab and clinic can increase cross-infection risks

Dental lab employees are at risk of infection from soiled impressions received from dental clinics. Contaminated items returned from dental labs to dental clinics can also become a source of cross-infection (Verran, Kossar and McCord, 1996; Sykes et al, 2019).

Conventional impressions from clinics have to be disinfected by labs to ensure the set dental cast does not contain microorganisms. These can also percolate within the material and remain viable for up to a week (British Dental Association, 2013; Sammy and Benjamin, 2016).

Using digital impressions significantly lowers the risk of cross-infection since there is no cast handling.

4. Manual creation of appliances/restorations increases contamination risks in the lab

Traditional production of dental restorations/appliances provides additional opportunities for contamination (Barker et al, 2014). Therefore, they require disinfecting, which extends the processing time.

Digital design solutions require significantly reduced handling (Suese, 2020; Ambili and Prasad, 2019). Furthermore, increased automation in dental appliance production processes require little or no human intervention (Rekow, 2020).

Speak to our specialists, request a demo or take advantage of our exclusive summer offer on all Trios models here.


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Sofou A, Larsen T, Fiehn N and Öwall B (2002) Contamination level of alginate impressions arriving at a dental laboratory. Clin Oral Invest 6: 161–5

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Vazquez-Rodrıguez I, Estany-Gestal A, Seoane-Romero J, Mora M, Varela-Centelles P and Santana-Mora U (2018) Quality of cross-infection control in dental laboratories. A critical systematic review. Int J Quality in Health Care 30 (7): 496–507

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