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Journal of Pharmacy & Bioallied Sciences Feb 2024This research study aimed to evaluate and compare the capability of four various bite registration materials to reproduce precise interocclusal relationships in the...
BACKGROUND
This research study aimed to evaluate and compare the capability of four various bite registration materials to reproduce precise interocclusal relationships in the vertical dimension.
MATERIALS AND METHODS
Ideal maxillary and mandibular casts were mounted on the semi-adjustable articulator in maximum intercuspation after mock tooth preparation on 46, 47, and 48. Models were scanned by the Medit T500 Dental Lab Scanner, and initial reading was noted at the predetermined points. Ten interocclusal bite registrations were made using four materials (CADbite, Jet Bite, Ramitec, and Aluwax). The mandibular model was demounted and again remounted using the interocclusal records, and the final reading was noted after scanning.
RESULTS
Ramitec showed superior results when compared to polyvinyl bite registration material and Aluwax, but the differences between Ramitec, CADbite, and Jet Bite were nonsignificant.
CONCLUSIONS
Although all four materials are suitable for clinical use, elastomeric materials showed superior results. In that, polyether was found to be the best.
PubMed: 38595573
DOI: 10.4103/jpbs.jpbs_990_23 -
Clinical Oral Investigations Apr 2024Reconstruction of a three-dimensional jaw position determined by a bite recording is an important aspect of prosthetic therapy. Different materials are used for this...
OBJECTIVES
Reconstruction of a three-dimensional jaw position determined by a bite recording is an important aspect of prosthetic therapy. Different materials are used for this purpose. In the dental technical workflow, recordings are used to mount a lower jaw cast in a patient-like spatial position relative to the upper jaw cast. We evaluated the accuracy of positioning under the influence of different jaw positions and materials.
MATERIALS AND METHODS
In an experimental setup, comprising an articulator, a pair of metal casts, and an optoelectronic measurement system, the spatial position of the incisal point and two condylar points were measured. To evaluate the accuracy of repeated repositioning of casts in the technical workflow, 324 measurements were taken from 108 recordings, consisting of silicone bite-stops made of addition curing silicone with 95 shore hardness, acrylic wafers, and wax recordings. The recordings were obtained in four jaw relations differing in vertical and protrusive components.
RESULTS
Of the three materials/material combinations examined, silicone showed the most consistent results across all measurements, followed by the acrylic wafer system, and then wax recordings. Generally, recordings with smaller gaps between the jaws and no protrusive components showed greater deviations compared to jaw positions with greater protrusion and higher vertical dimensions.
CONCLUSIONS AND CLINICAL RELEVANCE
To achieve reliable model mounting with high accuracy, recordings should include the use of a frontal jig and four small recording platelets made of silicone, especially if only a slight elevation of the vertical dimension is needed.
Topics: Humans; Jaw Relation Record; Mandible; Dental Articulators; Vertical Dimension; Silicones
PubMed: 38556612
DOI: 10.1007/s00784-024-05637-y -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Feb 2024This clinical study aimed to evaluate the accuracy of a fully digital technique for measuring sagittal condylar inclination (SCI), as well as validating whether...
OBJECTIVES
This clinical study aimed to evaluate the accuracy of a fully digital technique for measuring sagittal condylar inclination (SCI), as well as validating whether differences existed between the left and right SCI values of the same participant, to provide a reference for clinical practice.
METHODS
Ten participants with good occlusal relationship and normal temporomandibular joint were recruited. Three methods were used to measure the SCI values of the participants, namely, A (mechanical facebow transferring and mechanical articulator-based measuring method with physical protrusive interocclusal registration), B (face scan-based virtual facebow and virtual articulator-based measuring method with digital protrusive interocclusal registration), and C (jaw motion tracking system-based measuring method). With the group subjected to methods A and C as the control, the SCI values obtained by the three methods were statistically analyzed. The left and right SCI values of the same participant were also compared.
RESULTS
The left and right SCI values measured by method A were 41.70°±7.09° and 42.80°±8.62°, those by method B were 35.09°±12.49° and 37.63°±12.10°, and those by method C were 39.43°±8.72° and 38.45°±6.91°. No significant difference existed among the SCI values measured by the three methods (>0.05). Meanwhile, no statistical difference existed between the SCI values on the left and right sides of the same participant (>0.05).
CONCLUSIONS
The accuracy of the virtual facebow and digital protrusive occlusal registration based SCI measuring method was the same as that of mechanical facebow based and jaw motion tracking system-based methods. The SCI values on the left and right sides of the same participant were similar. Clinically, an appropriate SCI measurement and setting strategy can be selected based on the actual situations.
Topics: Humans; Mandibular Condyle; Jaw Relation Record; Temporomandibular Joint; Dental Articulators; Extraoral Traction Appliances
PubMed: 38475953
DOI: 10.7518/hxkq.2024.2023242 -
The Journal of Prosthetic Dentistry Mar 2024An artificial-intelligence (AI) based program can be used to articulate scans in maximum intercuspal position (MIP) or correct occlusal collisions of articulated scans...
STATEMENT OF PROBLEM
An artificial-intelligence (AI) based program can be used to articulate scans in maximum intercuspal position (MIP) or correct occlusal collisions of articulated scans at MIP; however, the accuracy of the AI program determining the MIP relationship is unknown.
PURPOSE
The purpose of the present clinical study was to assess the influence of intraoral scanner (IOS) (TRIOS 5 or i700) and program (IOS or AI-based program) on the accuracy of the MIP relationship.
MATERIAL AND METHODS
Casts of a participant mounted on an articulator were digitized (T710). A maxillary and a mandibular scan of the participant were recorded by using 2 IOSs: TRIOS 5 and i700. The scans were duplicated 15 times. Then, each duplicated pair of scans was articulated in MIP using a bilateral occlusal record. Articulated scans were duplicated and allocated into 2 groups based on the automatic occlusal collisions' correction completed by using the corresponding IOS program: IOS-corrected and IOS-noncorrected group. Three subgroups were created based on the AI-based program (Bite Finder) method: AI-articulated, AI-IOS-corrected, and AI-IOS-noncorrected (n=15). In the AI-articulated subgroup, the nonarticulated scans were imported and articulated. In the AI-IOS-corrected subgroup, the articulated scans obtained in the IOS-corrected group were imported, and the occlusal collisions were corrected. In the AI-IOS-corrected subgroup, the articulated scans obtained in the IOS-noncorrected subgroup were imported, and the occlusal collisions were corrected. A total of 36 interlandmark measurements were calculated on each articulated scan (Geomagic Wrap). The distances computed on the reference scan were used as a reference to calculate the discrepancies with each experimental scan. Nonparametric 2-way ANOVA and pairwise multiple comparison Dwass-Steel-Critchlow-Fligner tests were used to analyze trueness. The general linear model procedure was used to analyze precision (α=.05).
RESULTS
Significant maxillomandibular trueness (P=.003) and precision (P<.001) differences were found among the subgroups. The IOS-corrected and IOS-noncorrected (P<.001) and AI-articulated and IOS-noncorrected subgroups (P=.011) were significantly different from each other. The IOS-corrected and AI-articulated subgroups obtained significantly better maxillomandibular trueness and precision than the IOS-noncorrected subgroups.
CONCLUSIONS
The IOSs tested obtained similar MIP accuracy; however, the program used to articulate or correct occlusal collusions impacted the accuracy of the MIP relationship.
PubMed: 38458860
DOI: 10.1016/j.prosdent.2024.01.023 -
The Journal of Prosthetic Dentistry Feb 2024This technique uses 3 or 4 two-dimensional (2D) photographs, including a frontal headshot with a facebow and lip retractors, a profile headshot with a facebow and lip...
This technique uses 3 or 4 two-dimensional (2D) photographs, including a frontal headshot with a facebow and lip retractors, a profile headshot with a facebow and lip retractors on the right or left side, and a frontal headshot with a facebow during maximum smile without retractors. These 2D photographs are used to digitally mount casts on a virtual articulator.
PubMed: 38418301
DOI: 10.1016/j.prosdent.2024.01.032 -
The International Journal of... Feb 2024To compare the static and dynamic occlusion of all-ceramic single crowns designed by mechanical and virtual articulators, by evalua6ng the accuracy of occlusal contacts...
PURPOSE
To compare the static and dynamic occlusion of all-ceramic single crowns designed by mechanical and virtual articulators, by evalua6ng the accuracy of occlusal contacts of prostheses designed by virtual articulators and the feasibility of clinical application of CAD/CAM virtual articulators.
MATERIALS AND METHODS
Nine subjects with an average age of 27 years who needed crown repair were recruited. After preparation of the all-ceramic crowns, two zirconia crowns were designed and fabricated through digital procedures and traditional methods. The intraoral scanner, Geomagic software, and T-Scan analyzer were used to analyze the occlusal contact points, areas, and the occlusal force percentage peak before the treatment and after the two crowns were temporarily fixed.
RESULTS
There was a significant difference in the number of occlusal contact points and areas between the mechanical group and control group (preoperation group), but there was no obvious difference between the virtual group and control group. The occlusal contact overlapping areas of the virtual-control group were significantly larger than those of the mechanical-control group. The occlusal force percentage peak of the tested teeth was slightly larger in the mechanical group than in the virtual group.
CONCLUSIONS
The posterior single crown designed by a virtual articulator restored the intercuspal occlusal better than one designed by a mechanical articulator, and it produced less dynamic occlusal interference. This finding suggests that virtual articulators can provide guidance for the design and adjustment of the occlusal surface of posterior single crown prostheses.
Topics: Humans; Adult; Dental Articulators; Crowns; Computer-Aided Design; Molar; Ceramics; Dental Prosthesis Design
PubMed: 38381992
DOI: 10.11607/ijp.8298 -
Cureus Jan 2024The virtual articulator (VA) is a technology that simulates the jaw relation in a computer-generated setting. Augmented and virtual reality have been utilized as digital... (Review)
Review
The virtual articulator (VA) is a technology that simulates the jaw relation in a computer-generated setting. Augmented and virtual reality have been utilized as digital technology, which aids in many areas of dentistry and dental education. Today, a practicing dentist must keep up with the newer technologies, but with technology evolving so quickly it becomes challenging. In dentistry, the possibilities for digitization and technological advancements are limitless. Virtual articulators (VAs) allow a complete occlusion analysis using dental models that replicate all mandibular motions in static and dynamic scenarios. VA when executed in addition to other software enhances treatment planning and patient education, allowing quicker and more precise individualized diagnoses. The main objective of this study was to describe and evaluate the study outcomes in the available research on VAs, assess their needs, and evaluate their advantages and limitations in various aspects. A PubMed Central search was made of dental journals, with the identification of 135 articles out of which 30 were finally selected. The investigations conducted to evaluate the VA's dependability provide good visualization of the quantity and location of the dynamic interactions. A precise instrument for fully analyzing occlusion in a real patient is the virtual articulator.
PubMed: 38371021
DOI: 10.7759/cureus.52554 -
Beijing Da Xue Xue Bao. Yi Xue Ban =... Feb 2024To compare the trueness of incisal guidance of implant-supported single crowns designed by patient-specific motion (PSM) with that designed by average-value virtual...
OBJECTIVE
To compare the trueness of incisal guidance of implant-supported single crowns designed by patient-specific motion (PSM) with that designed by average-value virtual articulator (AVA).
METHODS
The study had recruited 12 participants with complete dentition and stable incisal guidance. An intraoral scanner was used to scan digital casts and record two types of patient-specific motion (data only including protrusive movement, and data including protrusive movement and lateral protrusive movement). The lingual surfaces of the maxillary incisors which guided the protrusive movement was selected and elevated to create a reference cast. A maxillary central incisor of original casts was vir-tually extracted and implanted to generate a working cast. The Dental system software program was used to design implant-supported single crowns with the anatomical coping design method. The incisal guidance was designed by different methods. The incisal guidance in control group was designed by the average-value virtual articulator. The incisal guidance in experiment groups was designed by the patient-specific motion only including protrusive movement (PSM1) and with the patient-specific motion including protrusive movement and lateral protrusive movement (PSM2). The incisal guidance of prosthesis designed by these 3 methods were compared with the original incisal guidance in Geomagic Control 2015 (3DSystem, America). The measurements included: Average of positive values, ratio of positive area and maximum value reflecting supra-occlusion; average of negative values, ratio of negative area and minimum value reflecting over-correction; and root mean square reflecting overall deviation.
RESULTS
Statistical data were collected using the median (interquartile range) method. The average of positive values, ratio of positive area and average of negative values of the PSM2 group were smaller than those of the control group [8.0 (18.8) μm . 37.5 (47.5) μm; 0 . 7.2% (38.1%); -109.0 (63.8) μm .-66.5 (64.5) μm], and the ratio of negative area of PSM2 group was larger than those of the control group [52.9% (47.8%) . 17.3% (45.3%)], with significant differences ( all < 0.05). The ratio of positive area [0.1% (7.0%)] and average of negative values [-97.0 (61.5) μm] of PSM1 group, were smaller than those of the control group, and the ratio of negative area [40.7% (39.2%)] of the PSM1 group was larger than that of the control group, with significant differences ( < 0.05). The average of positive values [20.0 (42.0) μm] and ratio of positive area of PSM1 group was larger than that of the PSM2 group with significant differences ( < 0.05).
CONCLUSION
To establish the incisor guidance of implant-supported single crowns, compared with the average-value virtual articulator and the patient-specific motion only including protrusive movement, the patient-specific motion including protrusive movement and lateral protrusive movement is more conducive to reducing the protrusive interference of prosthesis and improving the occlusal fit.
Topics: Humans; Incisor; Software; Maxilla; Crowns; Movement; Computer-Aided Design
PubMed: 38318900
DOI: 10.19723/j.issn.1671-167X.2024.01.013 -
The Journal of Prosthetic Dentistry Jan 2024Jaw tracking systems can record mandibular movement such as the repeatable reference position and excursive movements of the mandible. A technique for integrating the...
Integrating the repeatable reference position and excursive movements of the mandible acquired using a jaw tracker into the design procedures of an occlusal device: A technique.
Jaw tracking systems can record mandibular movement such as the repeatable reference position and excursive movements of the mandible. A technique for integrating the recorded repeatable reference position of the mandible and excursive movements captured using an optical jaw tracking system into the design procedures of an occlusal device is described. The mandibular motion of the patient is directly used to design the occlusal device, replacing the virtual articulator. The described technique aims to reduce the delivery time by incorporating the recorded motion of the patient into the virtual design of the occlusal device.
PubMed: 38238212
DOI: 10.1016/j.prosdent.2023.12.011 -
The Journal of Prosthetic Dentistry Jan 2024Patients with aberrant occlusal patterns, including constricted mastication patterns or occlusal dysfunction, may require occlusal equilibration. Conventional diagnostic...
Patients with aberrant occlusal patterns, including constricted mastication patterns or occlusal dysfunction, may require occlusal equilibration. Conventional diagnostic procedures involve diagnostic stone casts mounted in the articulator. During diagnostic procedures, occlusal equilibration methods are simulated on mounted stone casts to analyze the amount of dental structure that may need to be removed. A technique to virtually simulate an occlusal equilibration procedure is described. Digital data acquisition procedures include diagnostic casts acquired using an intraoral scanner and the repeatable reference position of the mandible or centric relation, excursive movements, and the mastication pattern captured using an optical jaw tracking system. The jaw tracker and dental design programs are used to simulate the occlusal equilibration.
PubMed: 38216378
DOI: 10.1016/j.prosdent.2023.12.004