Accuracy and reproducibility of the visualisation of occlusal contact points using analogue articulating foil or digital intraoral scanners in vitro.

AIM: The accuracy and reproducibility of occlusal contact points visualized by articulation foil (AF) should be investigated and then compared with contact points calculated by three different intraoral scanners (IOS). MATERIALS AND METHODS: Occlusal contact points were visualized on a standardized resin dental tooth model using AF 50 times with maximum intercuspidation and constant biting force. The points were photographed from a vertical position above the model and superimposed on a screen in order to test the reproducibility of the model. This was followed by fifty-fold repetition by scans and computation of the occlusal contact points by the respective IOS CS3600 (CS ScanFlow v.1 4th version), TRIOS 3 (Basic 2019), and CEREC Omnicam (Software version 5.1). The results of computation were captured with screenshots, and were then overlaid with the photographs of the AF. The image overlays were classified into five categories: category 1 = total overlapping of contact points, category 2 = partly overlapping, category 3 = adjacent contact points without overlapping, category 4 = contact points identified only by IOS, category 5 = contact points identified only by AF. All data were statistically evaluated (95% CI). RESULTS: In total, the visualisation of the occlusal contact points by the IOS were significantly less accurate and less reproducible compared to the AF (p < 0.05). In the combination of sensitivity and accuracy, the TRIOS3 by 3Shape showed significantly better results than the other IOS tested (p < 0.05). CONCLUSION: In vitro, AF displayed a significantly more accurate visualisation of the occlusal contact points than IOS.

Vaccination intentions generate racial disparities in the societal persistence of COVID-19.

We combined survey, mobility, and infections data in greater Boston, MA to simulate the effects of racial disparities in the inclination to become vaccinated on continued infection rates and the attainment of herd immunity. The simulation projected marked inequities, with communities of color experiencing infection rates 3 times higher than predominantly White communities and reaching herd immunity 45 days later on average. Persuasion of individuals uncertain about vaccination was crucial to preventing the worst inequities but could only narrow them so far because 1/5th of Black and Latinx individuals said that they would never vaccinate. The results point to a need for well-crafted, compassionate messaging that reaches out to those most resistant to the vaccine.