Intraoral Scanning Technology Research Articles

Assessing tooth wear progression in non-human primates: a longitudinal study using intraoral scanning technology.

Intraoral scanners are widely used in a clinical setting for orthodontic treatments and tooth restorations, and are also useful for assessing dental wear and pathology progression. In this study, we assess the utility of using an intraoral scanner and associated software for quantifying dental tissue loss in non-human primates. An upper and lower second molar for 31 captive hamadryas baboons (Papio hamadryas) were assessed for dental tissue loss progression, giving a total sample of 62 teeth. The animals are part of the Southwest National Primate Research Center and were all fed the same monkey-chow diet over their lifetimes. Two molds of each dentition were taken at either two- or three-year intervals, and the associated casts scanned using an intraoral scanner (Medit i700). Tissue loss was calculated in WearCompare by superimposition of the two scans followed by subtraction analysis. Four individuals had dental caries, and were assessed separately. The results demonstrate the reliability of these techniques in capturing tissue loss data, evidenced by the alignment consistency between scans, lack of erroneous tissue gain between scans, and uniformity of tissue loss patterns among individuals (e.g., functional cusps showing the highest degree of wear). The average loss per mm2 per year for all samples combined was 0.05 mm3 (0.04 mm3 for females and 0.08 mm3 for males). There was no significant difference in wear progression between upper and lower molars. Substantial variation in the amount of tissue loss among individuals was found, despite their uniform diet. These findings foster multiple avenues for future research, including the exploration of wear progression across dental crowns and arcades, correlation between different types of tissue loss (e.g., attrition, erosion, fractures, caries), interplay between tissue loss and microwear/topographic analysis, and the genetic underpinnings of tissue loss variation.

Assessing tooth wear progression in non-human primates: a longitudinal study using intraoral scanning technology

Intraoral scanners are widely used in a clinical setting for orthodontic treatments and tooth restorations, and are also useful for assessing dental wear and pathology progression. In this study, we assess the utility of using an intraoral scanner and associated software for quantifying dental tissue loss in non-human primates. An upper and lower second molar for 31 captive hamadryas baboons (Papio hamadryas) were assessed for dental tissue loss progression, giving a total sample of 62 teeth. The animals are part of the Southwest National Primate Research Center and were all fed the same monkey-chow diet over their lifetimes. Two molds of each dentition were taken at either two- or three-year intervals, and the associated casts scanned using an intraoral scanner (Medit i700). Tissue loss was calculated in WearCompare by superimposition of the two scans followed by subtraction analysis. Four individuals had dental caries, and were assessed separately. The results demonstrate the reliability of these techniques in capturing tissue loss data, evidenced by the alignment consistency between scans, lack of erroneous tissue gain between scans, and uniformity of tissue loss patterns among individuals (e.g., functional cusps showing the highest degree of wear). The average loss per mm2 per year for all samples combined was 0.05 mm3 (0.04 mm3 for females and 0.08 mm3 for males). There was no significant difference in wear progression between upper and lower molars. Substantial variation in the amount of tissue loss among individuals was found, despite their uniform diet. These findings foster multiple avenues for future research, including the exploration of wear progression across dental crowns and arcades, correlation between different types of tissue loss (e.g., attrition, erosion, fractures, caries), interplay between tissue loss and microwear/topographic analysis, and the genetic underpinnings of tissue loss variation.

Correlation between Depth of the Curve of Spee and Some Specific Malocclusion Characteristics in a Population from Sibiu County, Romania-A Cross-Sectional Study.

Background: This study aimed to investigate the relationship between the Curve of Spee (COS) depth and malocclusion characteristics in a population from Sibiu County, Romania. The research sought to understand how the COS's anatomical dimensions correlate with different classes of malocclusion and the position of the frontal teeth. Methods: A total of 265 participants from the Dentistry Ambulatory of the Military Hospital of Sibiu were included in this study. It employed digital intraoral scanning technology to measure the COS, overjet, and overbite, with malocclusion classification. Statistical analyses, including correlation and regression, were conducted to examine the relationships between COS depth, frontal teeth position, and malocclusion characteristics. Results: The average COS depth measured was 1.0564 mm, presenting variability when compared to existing literature. Most of the study participants had Class I malocclusion. A significant positive correlation between COS depth and overjet was identified, with no notable gender-based differences in these occlusal parameters. Conclusions: The findings affirm the integral role of COS in occlusal dynamics and malocclusion diagnosis. The COS measurement of a mean of 1.0564 mm, when compared to other results emphasizes the differences in occlusal curvature among various populations. The results contribute to a refined understanding of occlusal relationships, supporting the need for personalized orthodontic and prosthetic treatments based on precise anatomical measurements.

Optimizing digital implant impressions: Evaluating the significance of scan body image deficiency and alignment under varied scan body exposures.

In implant dentistry, the advent of intraoral scanning technology has revolutionized traditional clinical processes by streamlining procedures and ensuring predictable treatment outcomes. However, achieving accurate virtual implant positions using intraoral scanners and scan bodies can be influenced by various clinical and laboratory factors. This study aims to investigate the impact of scan body image capture deficiency and scan body alignment methods in computer-aided design (CAD) software on the accuracy of virtual implant positions, particularly in different implant depths. Three stereolithographic half-arch implant models with different implant depths were prepared, representing three scenarios of scan body exposure: full exposed scan body, 2/3 exposed scan body, and 1/3 exposed scan body. The scan body image capture deficiency and alignment methods were simulated using CAD software. The deviation of virtual implant positions obtained from different scenarios were evaluated using 3D analysis software. The highest angular and linear deviation (0.237±0.059 degrees, 0.084±0.068 mm) were found in the 1/4 upper and lower part scan body deficiency using the 1-point alignment method in the 1/3 exposed scan body. Two-way ANOVA analysis revealed significant effects of scan deficiency on virtual implant position deviations across all scan body exposures, except for the linear deviation when the scan body was exposed 2/3 of its length. Furthermore, scan deficiencies in the 1/4 upper and lower parts of the scan body significantly affected implant angular deviation regardless of scan body exposure, while implant linear deviation was specifically affected when the scan body was exposed to only 1/3 of its total length. Deficiencies in scan body acquisition, particularly in deep soft tissue situations, can lead to deviations in both angular and linear positioning of virtual implants. Employing appropriate scan body alignment methods such as a 3-point alignment approach demonstrates better accuracy compared to a 1-point alignment.

3D–3D dentition superimposition for individual identification: A study of an Eastern Chinese population

Recently, 3D dental intraoral scanning technology has been developed rapidly and applied widely in everyday dental practice. Since 3D dental scanning could provide valuable personal information, it enabled researchers to develop novel procedures for individual identification through 3D–3D dentition superimposition. This study aimed to test the applicability of this method in an Eastern Chinese population and propose a threshold for personal identification. For this purpose, 40 volunteers were recruited, and the initial 80 (upper and lower) 3D intraoral scans (IOS) were collected. After one year, 80 IOS of these volunteers were repeatedly collected. In addition, the other 120 IOS of 60 patients were extracted from the database. The 3D models were trimmed, aligned, and superimposed via Geomagic Control X software, and then the root mean square (RMS) value of point-to-point distance between the two models was calculated. The superimposition of two IOS belonging to the same individual was considered as a match, and superimposition of two IOS belonging to different individuals was considered as a mismatch. Totally, superimpositions of 80 matches and 3120 mismatches were obtained. Intra- and inter-observer errors were assessed through the calculation of relative technical error of measurement (rTEM). Mann-Whitney U test verified possible statistically significant differences between matches and mismatches (P < 0.05). The rTEM of intra- and inter-observer repeatability analyses was lower than 4.7 %. The range of RMS value was 0.05–0.18 mm in matches and 0.72–2.28 mm in mismatches without overlapping. The percentage of accurate identification reached 100 % in blind test through an arbitrary RMS threshold of 0.45 mm. The results indicated that individual identification through the 3D–3D dentition superimposition was effective in Eastern Chinese population. Successful identification could be achieved with high probability when the RMS value of the point-to-point distance of two dentitions is <0.45 mm.

Biomechanical effects of clear aligners with different thicknesses and gingival-margin morphology for appliance design optimization

The objectives of this study were to investigate the biomechanical effects of clear aligners (CAs) with various thermoplastic material thicknesses and gingival-margin designs for space closure in extraction treatment and to propose a computer-aided procedure to optimize CA design. The radiologic and intraoral scanning technology, invitro mechanical experiment, viscoelastic modeling, and finite element analysis (FEA) were integrated to establish an orthodontic simulation model. Twelve FEA models of CA were created, comprising combinations of 2 kinds of thicknesses (0.75 and 0.50 mm), 2 forms of gingival-margin shape (scalloped and straight), and 3 types of margin height (-2, 0, and 2 mm). Invitro testing was carried out to determine the actual properties of material thickness. A 0.75-mm-thick aligner resulted in greater periodontal ligament (PDL) stress than 0.50 mm, and there was no clear correlation between the control ability of tooth movement and the thickness. For different margin designs, PDL stress at -2 mm height was significantly lower than those with a higher border. Aligners with straight margins had higher stress than the scalloped aligners, whereas the differences were unnoticeable at 2 mm height. The optimized aligner with differential margin designs was recommended on the basis of biomechanical calculations, which facilitated the efficiency and control of tooth movement for multiple teeth. The effect of material thickness and margin design of CA on the force and movement differed in different teeth. Preferable CA designs of each tooth during different movement stages should be presented personalized under the guidance of precise biomechanics instead of pure morphologic analysis.

Validity and reliability of three-dimensional modeling of orthodontic dental casts using smartphone-based photogrammetric technology

The development of intraoral scanning technology has effectively enhanced the digital documentation of orthodontic dental casts. Albeit, the expense of this technology is the main limitation. The purpose of the present study was to assess the validity and reliability of virtual three-dimensional (3D) models of orthodontic dental casts, which were constructed using smartphone-based 3D photogrammetry. A smartphone was used to capture a set of two-dimensional images for 30 orthodontic dental casts. The captured images were processed to construct 3D virtual images using Agisoft and 3DF Zephyr software programs. To evaluate the accuracy of the virtual 3D models obtained by the two software programs, the virtual 3D models were compared with cone-beam computed tomography scans of the 30 dental casts. Colored maps were used to express the absolute distances between the points of each compared two surfaces; then, the means of the 100%, 95th, and 90th of the absolute distances were calculated. A Wilcoxon signed-rank test was applied to detect any significant differences. The differences between the constructed 3D images and the cone-beam computed tomography scans were not statistically significant and were accepted clinically. The deviations were mostly in the interproximal areas and in the occlusal details (sharp cusps and deep pits and fissures). This study found that smartphone-based stereophotogrammetry is an accurate and reliable method for 3D modeling of orthodontic dental casts, with errors less than the accepted clinically detectable error of 0.5 mm. Smartphone photogrammetry succeeded in presenting occlusal details, but it was difficult to accurately reproduce interproximal areas.

Effect of scanning speed, scanning pattern, and tip size on the accuracy of intraoral digital scans

Statement of problemCurrently available intraoral scanning technology makes intraoral scanning quicker and allows the use of smaller scanner tips. However, studies on the influence of scanning speed, tip size, and scanning patterns on scanning accuracy are lacking. PurposeThe purpose of this in vitro study was to evaluate the effect of scanning speed, scanning pattern, and scanner tip size on scanning trueness and precision. Material and methodsA total of 120 complete arch intraoral scans were made with an intraoral scanner (Emerald). The 3 variables were tip size (small and regular), scanning pattern (occlusal first and S-shaped), and scanning speed (slow, regular, and fast). Ten scans for each variable combination were made and exported as standard tessellation language (STL) files. A laboratory scanner (E4) was used for the reference scan. The exported images were analyzed with an image analysis software program (Geomagic Control X). Root-mean-square deviation (RMSD) values between the intraoral scans and the reference scan were calculated to assess trueness. RMSD values between each intraoral scan were calculated to assess precision. Three-way analysis of variance (ANOVA) was used to evaluate the influence of each variable, and Tukey HSD tests were used for multiple comparisons (α=.05). ResultsFor trueness evaluation, tip size was the only significant factor (P<.001). The scans made with a smaller tip showed lower trueness than the scans made with a regular tip. For precision evaluation, all 3 variables, tip size, scanning speed, and scanning pattern, had significant influence (P≤.001). The use of a small tip, fast scanning speed, and S-shaped scanning pattern made intraoral scanning less precise. ConclusionsThe use of a small scanner tip negatively affected both trueness and precision. Fast scanning speed and S-shaped scanning pattern produced scans with lower precision than regular or slow scanning speed and the occlusal-first scanning pattern.

Методика коррекции окклюзионных взаимоотношений зубных рядов с помощью цифровых технологий

The aim of the research. To develop a technique for correction of occlusal contacts using digital technology. Material and methods. Th is clinical study included 30 (16 male and 14 female) patients aged 33 to 69. Th e patients were divided into three groups. The first group consisted of 10 patients whose orthopaedic treatment was carried out with fi xed prostheses made of the E.max CAD material. Digital modelling of complete anatomical orthopaedic structures was carried out using a virtual articulator. In the patients of the second group, the frames of all-ceramic fixed prostheses were made in the KaVo ARCTICA CAD/CAM system from the ARCTICA ZS-Blank zirconium oxide. Then, the dental technician plastered the jaw models into a fully adjustable articulator Artex CR and applied the facing ceramic mass VM9. For the patients of the third group, the frames of all-ceramic fixed prostheses were made in the KaVo ARCTICA CAD/CAM system from zirconium oxide ARCTICA ZS-Blank. Then, the dental technician plastered the jaw models into a STRATOS 100 medium anatomical articulator and applied a VM9 ceramic facing mass. Occlusion was registered using T-ScanIII. Statistical analysis of the results obtained was carried out in the R soft ware environment using Fisher’s exact test. Results. Regarding the occlusal balance, the technique for manufacturing of fixed prostheses using a virtual articulator is distinguishable from the methods for manufacturing of orthopedic structures using patient-specific and average-value articulators at a significance level of p&lt;0.0167. At this level of significance, there was no statistically signifi cant diff erence between the methods of fixed prostheses manufacturing using patient-specifi c and average-value anatomical articulators. Conclusion. Th e use of digital intraoral scanning technology, modeling of dentures using a virtual articulator and manufacturing of orthopedic structures in CAD/CAM systems makes it possible to obtain non-removable dentures that do not require correction of occlusal contacts at the stage of fi tting in the oral cavity. Th e proposed method for correction of occlusal contacts with digital technology is highly effective.

Potential of intraoral optical scanning to evaluate motor skills' improvement for tooth preparation: A prospective cohort study.

This prospective cohort study investigated the potential of digital assessment using intraoral scanning (IOS) combined with software analysis (prepCheck) to evaluate the outcome of repetitive tooth preparation and its influence on the acquisition of motor skills in dental students. Twenty-six students completed 177 full-crown preparations of the same tooth in six practice sessions followed by a final examination. Preparations were assessed digitally using prepCheck and conventionally by calibrated faculty instructors. In addition, students assessed their own performance and this was compared with the instructors' assessments. Conventional assessment showed that students preparations improved over time, with 43.5% of students receiving score 2 (highest grade) at the fifth practice session. With the prepCheck assessment, statistically significant improvements indicated by an enlarged area within the tolerance range set at 0.2mm were found between the first and the second practice session (7.5% improvement; 95% CI: 2.2%, 12.7%, p=0.006), and between the first run and the final exam preparation (6.7%; 95% CI: 1.7%, 12.5%, p=0.011). Agreement between instructor/student assessments was best immediately after students received visual feedback using prepCheck (76% agreement; Spearman's rho 0.78). These data indicate that IOS technology was useful for student's self-evaluation by visual feedback.

Abstracts from the World Federation for Laser Dentistry—Asia Pacific Division Virtual Conference July 16–17, 2021

Abstracts from the World Federation for Laser Dentistry—Asia Pacific Division Virtual Conference July 16–17, 2021

Feasibility of Intraoral Scanning for Data Acquisition of Maxillectomy Defects.

To assess the feasibility of using an intraoral scanner for data acquisition of maxillectomy defects. In 10 patients who had undergone a maxillectomy, the maxillectomy defects in dentate and edentulous maxillary arches were intraorally scanned. Intraoral photographs were also taken using a digital camera for comparison. Adequate scanning was achieved for the nondefect side of the maxilla and for residual teeth. In some cases, it was impossible to scan the maxillectomy defect, especially the deep sites. Improved intraoral scanning technology will increase the feasibility of its use in maxillofacial prosthetics.

Research and development of clinical application accuracy of intraoral three-dimensional scanning technology

Intraoral three-dimensional scanning technology has been adopted in stomatology field and developed rapidly with improved accuracy. At present, the scanning accuracy of the intraoral three-dimensional scanners used in restoration of single crown, three unit fixed partial bridge and single implant crown satisfies the clinical requirements. While for restoration of multi-unit fixed, the scanning accuracy is not enough. There are still technical bottlenecks for scanning functional motion boundary of soft tissue, especially for direct acquisition of edentulous functional impressions. Through literature review and analysis, we summarize the intraoral scanning accuracy of oral hard and soft tissues, and analyze the clinical applicability and limitations of intraoral scanning technology, providing reference for clinical application.

Assessment of intraoral scanning technology for multiple implant impressions - A systematic review and meta-analysis.

Background:Intraoral scanner (IOS) is a medical device used for capturing direct optical impressions and composed of a handheld camera (hardware), a computer and software. Digital impressions by intraoral scanning have become an increasingly popular alternative to conventional impressions. The aim of this systematic review is to assess the studies regarding the various available technologies for IOS and evaluate the most accurate IOS system for cases with multiple implants and identify the factors that can influence its accuracy.Materials and Methods:A comprehensive electronic search was done in online databases, 'Pubmed', 'Google Scholar' and 'Cochrane' based on pre-determined eligibility criteria. In-vitro studies, In-vivo studies and Randomized controlled trials assessing the accuracy of intra-oral scanner technology were selected after thorough screening. The search strategy covered all studies published until February 2019 and yielded a total of 11 articles out of which 8 studies were determined to fulfil the inclusion criteria and were selected for this review. Data extraction from the included studies was conducted by the primary author and reviewed by the second author.Results:The information collected included sample size and population, study design, intervention, scanning methods, comparisons and outcome measures. 5 out of 8 included studies compared the distance deviation of the acquired scans from the true values while the remaining 3 studies gave trueness and precision values as the outcome variables. A forest plot on scanner precision displayed slightly higher precision levels in the TRIOS scanner compared to the other intraoral scanners.Conclusion:Despite the limitations this study, it can be concluded that active wavefront sampling is more accurate than the other intraoral scanning technology employed by commercial scanners.

Augmented Reality Implementations in Stomatology

Augmented reality has a wide range of applications in many areas that can extend the study of real objects into the digital world, including stomatology. Real dental objects that were previously examined using their plaster casts are often replaced by their digital models or three-dimensional (3D) prints in the cyber-physical world. This paper reviews a selection of digital methods that have been applied in dentistry, including the use of intra-oral scanning technology for data acquisition and evaluation of fundamental features of dental arches. The methodology includes the use of digital filters and morphological operations for spatial objects analysis, their registration, and evaluation of changes during the treatment of specific disorders. The results include 3D models of selected dental arch objects, which allow a comparison of their shape and position during repeated observations. The proposed methods present digital alternatives to the use of plaster casts for semiautomatic evaluation of dental arch measures. This paper describes some of the advantages of 3D digital technology replacing real world elements and plaster cast dental models in many areas of classical stomatology.

Labial soft tissue contour dynamics following immediate implants and immediate provisionalization of single maxillary incisors: A 1-year prospective study.

Soft tissue dynamics in the esthetic zone are gaining increasing attention in recent years. Emerging intraoral scanning technology allows easier capture of soft tissue contours. To quantitatively assess the time-dependent contour alterations of labial soft tissue following single immediate implants and immediate provisionalization (IIPP) in maxillary incisors via intraoral scanning. This was a prospective cohort study. Thirty eligible consecutive patients were included and received immediate replacement of a failure maxillary single incisor. A screw-retained immediate restoration was delivered for each patient. Subsequently, the anterior maxillary region was scanned by an intraoral scanning system at four time points: preoperation (baseline, BL), 3 months (3 m), 6 months (6 m), and 12 months (12 m). The Standard Tessellation Language files were exported to a dedicated software and superimposed for visual analysis. At 3, 6, and 12 months, the mid-facial mucosa level (ML) was assessed, and the precise three-dimensional (3D) configuration of the altered volume was calculated and reconstructed for visual analysis. Furthermore, quantitative analysis of the reconstructed morphology was performed using the following parameters: mean change in thickness (△d), mesio-distal width (w), coronal-apical height (h), and horizontal and vertical position of the thickest point represented by coordinates (x, z). Twenty-seven of thirty enrolled patients were finally available for analysis at the 1-year follow-up. In general, the frontal view of the reconstructed volume exhibited a crescent shape. The mid-facial ML change at 3, 6, and 12 months was -0.05 ± 0.36 mm, -0.03 ± 0.32 mm, and -0.24 ± 0.37 mm, respectively (P = .012). The mean change in thickness at 3 months (△d3m ), 6 months (△d6m ), and 12 months (△d12m ) was 0.50 ± 0.19 mm, 0.59 ± 0.21 mm, and 0.62 ± 0.22 mm, respectively (P <.001). At 12 months, nine patients had a △d less than 0.5 mm. The mean △d3 m /△d12 m and △d6 m /△d12 m was 0.81 ± 0.17 and 0.96 ± 0.13. The w, h, x, and z results showed no significant differences during the 1-year observation (P = .126, P = .324, P = .635, P = .263). At 12 months, w, h, x, and z were 11.57 ± 1.77 mm, 6.46 ± 2.01 mm, 0.03 ± 1.43 mm, and 2.16 ± 0.65 mm, respectively. During the 1-year observation following single IIPP treatment in maxillary incisors, the labial soft tissue contour showed a continuous alteration resulting in a mean change in thickness of 0.62 mm that occurred mainly in the first 3 months and tended to be relatively stable after 6 months, while the crescent-like shape, width, height, and thickest point position of the alteration volume remained stable after 3 months. No advanced mid-facial recession was observed.

A predictable all-digital workflow to retrofit a crown to an existing removable prosthesis

The task of fabricating a new crown under an existing removable partial denture presents challenges for the dentist, technician, and patient. The main concern is accurately communicating the configuration of the rest, retentive clasps, and reciprocal elements to the laboratory technician without temporarily depriving the patient of the prosthesis. A variety of solutions involving stone cast alterations and elastomeric or resin indexes have been used for this task. However, these methods require significant additional time and technique-sensitive work by the operator and technician. More recent approaches using digital technologies require many of these traditional steps, each of which introduces potential inaccuracy and labor cost. This updated approach eliminates the inaccuracies associated with manual manipulation by the technician by leveraging contemporary intraoral scanning technology and a completely digital workflow to predictably and accurately fabricate a crown under an existing prosthesis.

Intra-Oral 3D Scanning for the Digital Evaluation of Dental Arch Parameters

Intra-oral scanning technology has brought a completely new approach to examination methods in dentistry. In comparison to traditional plaster casts, it allows more precise digital analysis of dental arch components during the treatment of dental disorders. Data acquired can also be used for the creation of three-dimensional (3D) models using 3D printers. This paper describes a data acquisition system, the mathematical processing of resulting three-dimensional model, and the statistical analysis of selected parameters of the dental arch. The study aims at comparing the results achieved from 20 models of the same individual acquired by different specialists. The proposed methodology includes mathematical rotation of objects into the optimal plane defined by the teeth tops’ location to increase the accuracy of the resulting parameters. The mean evaluated distances between canines (3-3) and premolars (5-5) are 24.29 mm and 37.98 mm, respectively, for the lower dental arch. The proposed object rotation increased these distance by 0.9% and 1.4%, respectively, reducing the rotation error. Moreover, the variability of results decreased and the mean value of the coefficient of variation was lowered by 12%. Image registration was then used to evaluate changes of dental arch parameters. This paper presents the advantages of digital models for visualisation of the dental arch allowing its flexible rotation and evaluation of its parameters.

Intraoral Scanner로 촬영된 치아 이미지의 정렬

This paper proposes a framework to automatically align Dental range image captured by depth sensors like the Microsoft Kinect. Aligning dental images by intraoral scanning technology is a difficult problem for applications requiring accurate model of dental-scan datasets with efficiency in computation time. The most important thing in dental scanning system is accuracy of the dental prosthesis. Previous approaches in intraoral scanning uses a Z-buffer ICP algorithm for fast registration, but it is relatively not accurate and it may cause cumulative errors. This paper proposes additional Alignment using the rough result comes after intraoral scanning alignment. It requires that Each Depth Image of the total set shares some overlap with at least one other Depth image. This research implements the automatically additional alignment system that aligns all depth images into Completed model by computing a network of pairwise registrations. The order of the each individual transformation is derived from a global network and AABB box overlap detection methods.

Intraoral scanning of hard and soft tissues for partial removable dental prosthesis fabrication

This article provides proof of concept for the use of intraoral scanning technology to record hard and soft tissue morphology for the fabrication of a cast partial removable dental prosthesis. An open source intraoral scanner was used to scan the hard and soft tissues to create a stereolithographic file that was subsequently imported into a computer-aided design software program for the digital/virtual design of a partial removable dental prosthesis framework. Computer-aided design and computer-aided manufacturing technology was then used to fabricate a resin framework that was trial placed to evaluate accuracy and for conventional investing and casting with a cobalt-chromium alloy. The cast framework and definitive prosthesis were judged to be clinically accurate in fit, stability, and retention.