For dental impressions, the transition from the traditional method to the digital method has marked a revolution in the field of dentistry. Thanks to increasingly innovative technological tools, taking dental impressions of patients has become a much faster, less invasive and more precise process.
What factors affect the accuracy of dental impressions?
Although the transition from the traditional to the digital method has improved the accuracy of dental impressions, it is always advisable to make sure that there are no factors that could alter the accuracy of the images, even in the case of using highly technological tools such as intraoral scanners .
The factors that can affect the accuracy of the impressions can be:
- ambient light
- presence of liquids in the oral cavity: saliva, blood and gum fluid
- oral cavity moisture
The light of the surrounding environment is the variable that can most affect the accuracy of the images because it could give rise to a phenomenon of refraction of light.
The presence of liquids in the oral cavity, on the other hand, which can also be conditioned by anesthesia or by some pharmacological therapies, could also affect the accuracy of the images of the intraoral scanner, but scientific research is not yet certain about this hypothesis.
Although the dentist uses a compressed air tool and aspirator to remove saliva from the oral cavity during the dental impression taking phase, the physical and chemical properties of the liquids could affect the scan of the teeth.
What does scientific research tell us?
In a recent study published in the Journal of Prosthodontics January 2022, the researchers evaluated how much the presence of liquids on the surfaces of the teeth could influence the accuracy and precision of the dental impressions taken through intraoral scanners and how effective the drying methods, mainly with compressed air, could be in excluding the presence of saliva and liquids from the teeth and oral cavity.
Research stages
- A mandibular maxilla model was scanned using a computed tomography scanner leveraging a scanning platform designed to simulate three specific tooth surface states in modes: dry, wet, and dry.
- Two liquids were used for the test: ultrapure water and artificial saliva.
- Two intraoral scanners were employed to scan the maxilla 10 times for each condition.
- All scan data was processed and analyzed using dedicated software to evaluate accuracy and veracity.
Results
From the information processing it emerged that for wet surfaces the accuracy and precision of the images were found to be less accurate.
Accuracy errors caused by the presence of liquids were mainly distributed in the pits and fissures of the occlusal surfaces of the posterior teeth, in the interproximal area of the teeth and at the marginal level of the abutments.
The presence of saliva or liquids on the surface of the teeth affects the accuracy of dental impressions obtained with intraoral scanning, but drying with a three-way syringe can reduce scan errors.
The presence of saliva or liquids on the surface of the teeth affects the accuracy of dental impressions obtained with intraoral scanning, but drying with a three-way syringe can reduce scan errors.
