Purpose: The variation in findings with regards to the accuracy and precision of intraoral scanners for shade selection are no doubt confusing for clinicians who may find it difficult to make evidence‐based decisions. The aim of this systematic review is to provide a comprehensive and in‐depth assessment of available studies to determine the viability of using intraoral scanners for the purpose of shade matching. The PICO‐guided research question is as follows: when shade matching, are intraoral scanners as valid as visual or other digital shade measuring devices in determining tooth colors.Methods: Electronic databases including PubMed/MEDLINE, SCOPUS, EBSCO, Cochrane, and ProQuest were systematically searched for articles published between January 1, 2011 and December 30, 2021 using the main search terms: “intraoral scanners,” “scanners,” “TRIOS,” “CEREC,” “Planmeca,” “Medit,” “digital dentistry” in concurrence with one of the following keywords: “EasyShade” OR “shade selection” OR “shade matching” OR “shade” OR “tooth color” OR “tooth shade” OR “digital shade matching.” Bibliographies of included articles and the following journals were searched for relevant articles: Journal of Prosthetic Dentistry, Journal of Prosthodontics, Journal of Esthetic and Restorative Dentistry, Journal of Advanced Prosthodontics, and Journal of Dentistry. A total of 15 articles were included in the review.Results: Intraoral scanners are highly repeatable for shade matching, and outperformed visual shade matching. Accuracy varied significantly between studies, with the majority recommending the use of visual shade matching to confirm/verify the intraoral scanner results. Setting intraoral scanners to the Vita 3D Master shade guide improved both accuracy and precision. Shade matching with intraoral scanners may be influenced by external factors such as ambient light sources and incorrect use or manipulation.Conclusion: Intraoral scanners set to the Vita 3D Master shade guide may be used for shade matching, but shade should be verified with visual shade matching. Further studies are required to address limitations of current studies.
Alloys of cobalt chromium have been used for decades to create frameworks for removable partial dentures. While cobalt chromium has multiple advantages, such as strength and light weight, the casting process is laborious and requires special care to ensure that human error is minimized. Furthermore, the display of metal clasps in these frameworks may be considered a limitation at times, especially with esthetically demanding patients. The introduction of digital technology to manufacturing in dentistry has brought forward new methods of fabricating cobalt chromium frameworks, some of which eliminate the casting process. Moreover, the development of high-performance polymers for use as removable partial denture frameworks brings multiple advantages, but raises concerns over design guidelines and principles. This review examines alternatives to conventionally cast frameworks so that clinicians may make evidence-based decisions when choosing framework materials and fabrication methods in the rapidly advancing world of digital dentistry.
14 November 2017 in International Journal of Dentistry
Cognitive decline is one of the major causes of disability among the aging population. The aim of this study was to explore the relationship between oral health parameters (number of teeth, chewing ability, and presence of a denture) and cognitive function in the elderly across the UAE. Fifty persons (age ≥ 60; 71.26 ± 10.23) were enrolled in the study. Cognitive status was assessed using the standardized mini-mental state examination (SMMSE) and accordingly, cognitively normal subjects scoring ≥24 were considered as the control group and cognitively impaired individuals scoring ≤23 were considered as the low scoring group. Chewing ability was examined, number of teeth was noted, and demographical data was collected. The results of this pilot study showed that individuals with low SMMSE scores were significantly less educated () and had fewer number of remaining teeth () and impaired chewing ability (). These results demonstrate a significant link between the number of teeth, chewing ability, and cognitive function. However, this pilot study had its limitations and was the first of its kind in the UAE and Gulf region; therefore, future research addressing the limitations is needed to further explore this association.
Purpose: To assess the influence of interdental spaces and scanning the palate on the accuracy of maxillary scans acquired using three intraoral scanners (IOSs).Materials and Methods: A virtual completely dentate maxillary cast without interdental spaces was obtained and modified to create 1, 2, and 3 mm of interdental spacing between the anterior teeth. These three files (reference standard tessellation language files) were used to print three reference casts. The reference casts were scanned using three IOSs: TRIOS4, iTero Element 5D, and Aoralscan2. Three groups were created based on the interdental spaces: 0, 1, 2, and 3 mm (n = 10). The groups were subdivided into two subgroups: no palate (NP subgroup) and palate (P subgroup). The reference STL files were used to measure the discrepancy with the experimental scans by calculating the root mean square (RMS) error. Three‐way analysis of variance (ANOVA) and post hoc Tukey pairwise comparison tests were used to analyze trueness. The Levene test was used to analyze precision (α = 0.05).Results: Trueness ranged from 91 to 139 μm and precision ranged from 5 to 23 μm among the subgroups tested. A significant correlation was found between IOS*group (p<0.001) and IOS*subgroup ( p<0.001). Tukey test showed significant trueness differences among the interdental spaces tested (p<0.001). The 1‐ and 2‐mm groups obtained better trueness than the 0‐ and 3‐mm groups (p<0.001). An 11 μm mean trueness discrepancy was measured among the different interdental space groups tested. The P subgroups demonstrated significantly higher trueness when compared to the NP subgroups (p<0.001). The discrepancy between the maxillary scans with and without the palate was 4 μm. Significant precision discrepancies were found (p = 0.008), with the iTero group showing the lowest precision.Conclusion: Interdental spaces and incorporation of the palate on maxillary intraoral scans influenced trueness and precision of the three IOSs tested. However, the scanning discrepancy measured may be of no clinical relevance.