Influence of object translucency on the scanning accuracy of a powder-free intraoral scanner: A laboratory study

Objective This in vitro study compares the newest generation of intraoral scanners to their older counterparts, and tests whether material substrates affect the trueness and precision of intraoral scanners (IOS). Material and methods A custom model, used as the reference standard, was fabricated with teeth composed of different dental materials. The reference standard scan was obtained using a three‐dimensional (3D) optical scanner, the ATOS III. Experimental scans were obtained using eight different IOS, operated by experienced clinicians, using the manufacturer's recommended scanning strategy. A comprehensive metrology program, Geomagic Control X, was used to compare the reference standard scan with the experimental scans. Results For all scanners tested, except Trios3, the substrate does influence the trueness and precision of the scan. Furthermore, differences exist when comparing the same substrate across different scanners with some of the latest generation scanners clearly leaping ahead of the older generation regarding both trueness and precision. Conclusions Substrate type affects the trueness and precision of a scan. Active Triangulation scanners are more sensitive to substrate differences than their parallel confocal counterparts. Some scanners scan certain substrates better, but in general the new generation of scanners outperforms the old, across all substrates. Clinical significance The substrates being scanned play an import role in the trueness and precision of the 3D model. The new generation of scanners is remarkably accurate across all substrates and for complete‐arch scanning.

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

The effect different substrates have on the trueness and precision of eight different intraoral scanners

Dutton

Ludlow

Mennito

et al. 2019

“…Natural teeth have varying degrees of translucencies, and shades, and restorative materials, gingival and mucosal tissues exhibit optical qualities very different than those of scanned artificial models or dentoforms . This is further explored by Hong Li et al, where it was found that objects with high translucency scanned with less accuracy and more morphological distortions . This study addresses this issue by using a human maxilla harvested from a fresh cephalus and kept fresh throughout the study to preserve dimensional stability.…”

Section: Introductionmentioning

confidence: 99%

“…16 This is further explored by Hong Li et al, where it was found that objects with high translucency scanned with less accuracy and more morphological distortions. 17 This study addresses this issue by using a human maxilla harvested from a fresh cephalus and kept fresh throughout the study to preserve dimensional stability.…”

mentioning

confidence: 99%

Evaluation of the trueness and precision of complete arch digital impressions on a human maxilla using seven different intraoral digital impression systems and a laboratory scanner

Mennito

Evans

Nash

et al. 2019

Objectives An impression accuracy study using a cadaver maxilla was performed using both prepared and intact teeth as well as palatal tissue. Materials and Methods Three crown preparations were performed on a cadaver maxilla. Seven different digital impression systems along with polyvinylsiloxane impressions were used to create digital models of the maxilla. Three‐dimensional (3D) files of the experimental models were compared to a master model. The 3D files were overlaid and analyzed using a comparison software to create color coded figures that were measured for deviations between the master and experimental models. Results For scanning tooth structure, only the Planscan was significantly less accurate than the rest of impression techniques. No significant differences in accuracy were found between models created using digital impressions and those created from traditional vinyl polysiloxane impressions with cross arch deviations ranging from 18 to 39 μm for each. Conclusions Impressions taken using all digital impression systems, save for the Planscan, were able to accurately replicate the tissues of a complete arch human maxilla. Clinical Significance Studies examining accuracy of digital impression systems have generally been performed on materials other than dental tissues. Optically, materials such as plastic and metal have properties different from enamel and dentin. This study evaluates accuracy of digital impression systems on human dentin, enamel, and soft tissues.

“…5,6 Different studies have analyzed the relationship between technology employed by an IOS system and the accuracy of its acquisition procedure. [7][8][9][10][11][12][13][14][15][16][17] Factors that could impact the accuracy of a digital impression performed by IOS 18 have also been studied, namely handling and learning curve, 19,20 calibration, 21 scanning protocol, [22][23][24] AMbient light scanning conditions, 25 surface characteristics, [26][27][28][29] mobile tissue, 30 reflective restorations, and/or presence of saliva. 19,[31][32][33] Digital impression techniques are a clinically acceptable alternative to conventional impression methods in fabrication of tooth and implant-supported crowns and short fixed dental prostheses (FDPs).…”

Section: Introductionmentioning

confidence: 99%

Workflow description of additively manufactured clear silicone indexes for injected provisional restorations: A novel technique

Revilla‐León

Fountain

Piedra‐Cascón

et al. 2019

Objective The present article describes the digital workflow protocol for additive manufacturing (AM) of a clear silicone index to be used for an injected provisional restoration fabrication. Clinical considerations The incorporation of CAD software and AM technologies have allowed the integration of a new way to fabricate conventional diagnostic wax‐ups and silicone indexes for preparing diagnostic mock ups, direct composite restorations, or provisional restorations. Although the conventional concept remains, the protocol differs. Conclusions This workflow provides a more efficient and accurate procedure with the reduction of time and cost compared to conventional technique. Clinical Significance The digital workflow protocol described for AM of a clear silicone index to be used for an injected provisional restoration fabrication is time and cost efficient compared to conventional procedures.