-
Journal of Prosthodontics : Official... Jan 2023The ever-expanding world of digital technology has produced many changes, including the availability of virtual articulators. The use of such digital technology requires... (Review)
Review
The ever-expanding world of digital technology has produced many changes, including the availability of virtual articulators. The use of such digital technology requires an understanding of the features that have been available with different mechanical articulators. These features include such items as facebow, intercondylar distance, incisal guide table, condylar inclination, reference plane, lateral condylar inclination, immediate mandibular translation, and ability to verify a centric relation record. This paper reviews the adjustable features that have been available with different types of mechanical articulators so that clinicians can determine if these features should be included in the virtual articulators they choose to use. Regardless of whether one is utilizing a mechanical or virtual articulator, the rationale for which type of articulator to select is the same and is predicated on the needs of the patient, the occlusal philosophy of the clinician, and the required accuracy.
Topics: Humans; Dental Articulators; Mandible; Tooth; Centric Relation; Jaw Relation Record
PubMed: 35344633
DOI: 10.1111/jopr.13517 -
Journal of Dentistry Jan 2023This prospective crossover clinical trial aimed to compare the complete-digital and -analog workflows in terms of occlusal adjustment of 3-unit tooth-supported fixed... (Clinical Trial)
Clinical Trial
AIM
This prospective crossover clinical trial aimed to compare the complete-digital and -analog workflows in terms of occlusal adjustment of 3-unit tooth-supported fixed dental prostheses, operator, and patient preferences.
MATERIALS AND METHOD
This study included twelve patients receiving fourteen 3-unit posterior FDPs. 2 FDPs were made for each restoration site: one fabricated in complete-digital workflow comprising intraoral scan with static bite registration (Trios 3) and a monolithic zirconia FDP (test); the other fabricated in complete-analog workflow comprising conventional impression/face-bow transfer and a porcelain-fused-to-metal FDP (control). The FDPs (n=28) were intraorally/provisionally fixed, and quadrant-like intraoral scans were taken for every FDP before & after their occlusal adjustments. Pre- and post-adjustment scans of each FDP were then superimposed using best-fit alignment (GOM Inspect) to measure the volumetric occlusal adjustment amount (mm) (3Matic) (Mann Whitney U, α=0.05). The patient and operator experience for digital and analog workflows were evaluated using visual analog scales (Wilcoxon test, α=0.05).
RESULTS
Mean occlusal adjustments were 7.63 mm [±7.02] and 25.95 mm [±39.61] for test and control groups, respectively. The volumetric adjustment difference was clinically noticeable but not significant (P=0.12). The impression and digital workflow adjustment were perceived more favorably by both operator (P=0.003, P=0.046, respectively) and the patients (P=0.003, P=0.002, respectively).
CONCLUSIONS
Within the limitations of this clinical study, the complete digital workflow with digital static bite-registration provided high occlusal accuracy for short-span tooth-supported FDPs. In addition, the patient and operator preferences significantly favored the digital workflow.
CLINICAL SIGNIFICANCE
Complete-digital workflow employing intraoral scanning and model-free fabrication of monolithic-Zr short-span tooth-supported FDPs offers an effective treatment modality with sufficient occlusal accuracy. Therefore complete-digital workflow is a valid alternative for complete-analog workflow comprising conventional impression, face-bow transfer, and use of a semi-adjustable articulator.
Topics: Humans; Computer-Aided Design; Dental Prosthesis Design; Occlusal Adjustment; Prospective Studies; Workflow; Zirconium; Cross-Over Studies
PubMed: 36403691
DOI: 10.1016/j.jdent.2022.104365 -
The Journal of Craniofacial Surgery Sep 2021Orthognathic surgery with surgery-first concept inevitably leads to an increase in posterior vertical dimension and anterior mandibular movement, causing a relapse. This...
Orthognathic surgery with surgery-first concept inevitably leads to an increase in posterior vertical dimension and anterior mandibular movement, causing a relapse. This case report introduces a digital technique for predictable surgical outcome in mandibular setback with the surgery-first orthognathic concept using digital articulator. Intraoral scans and a digital articulator were used to simulate the mandibular position after surgery and to predict postoperative increase in vertical dimension and its expecting forward movement of mandibile. This was incorporated in surgical planning. Sequential cone-beam computed tomography evaluation showed stable condylar position at 3 and 6 months after surgery. Thus, a digital articulator can be used to simulate the surgical outcome and to predict postsurgical increase in vertical dimension for better treatment planning.
Topics: Adult; Cephalometry; Cone-Beam Computed Tomography; Dental Articulators; Humans; Mandible; Mandibular Condyle; Orthognathic Surgical Procedures; Vertical Dimension
PubMed: 33534324
DOI: 10.1097/SCS.0000000000007477 -
The International Journal of... 2022Various types of digital dental technologies have been successfully implemented as a part of dental treatment to improve predictability and efficiency of dental...
Various types of digital dental technologies have been successfully implemented as a part of dental treatment to improve predictability and efficiency of dental procedures. Virtual smile design can be used to enhance predictability from an esthetic perspective, and the virtual articulator can be a useful tool to create a desired occlusal scheme. This case series describes a fully digital workflow that can predictably achieve desired esthetic and functional outcomes. The proposed protocol also includes other currently available digital technologies, such as intraoral scanning, computer-aided design, milling, and 3D printing. Three clinical cases are presented to describe the workflow in detail.
Topics: Computer-Aided Design; Esthetics, Dental; Humans; Smiling; Workflow
PubMed: 35353083
DOI: 10.11607/prd.5328 -
The Journal of Prosthetic Dentistry Feb 2022A digital quantitative occlusal analyzer with claimed lower cost and easier maneuverability has been introduced to replace conventional methods. However, information...
STATEMENT OF PROBLEM
A digital quantitative occlusal analyzer with claimed lower cost and easier maneuverability has been introduced to replace conventional methods. However, information regarding its performance is scarce.
PURPOSE
The purpose of this in vitro study was to evaluate the reliability and repeatability of a newly introduced digital occlusal analysis device (Accura) and to compare it with an established occlusal analyzer (T-scan Novus).
MATERIAL AND METHODS
The sensor films of both devices were positioned between titanium maxillary and mandibular models that were equilibrated and arbitrarily mounted on a semiadjustable articulator. Compressive force was applied to the upper arm of the articulator with a universal testing machine, increased gradually to 50 N, and then released automatically. The time and force measurements from the universal testing machine and the tested devices were recorded by operating software programs. Five articulating film sensors of each device were tested 3 times each by 2 examiners and were repeated on consecutive days, totaling 60 trials per device. Reliability was defined as an agreement between the loaded force and measured force. Repeatability was defined as an agreement between repeated measurements of the Accura and T-scan Novus. Intraclass correlation coefficient was calculated for the statistical analysis (α=.05).
RESULTS
The calculated intraclass correlation coefficient of the Accura and the universal testing machine was 0.952. The intraclass correlation coefficient of the T-scan Novus and the universal testing machine was 0.963. Intraclass correlation coefficients that were calculated to compare the data acquired from different days were 0.938 for the Accura and 0.911 for the T-scan Novus.
CONCLUSIONS
The experimental results indicated that the reliability of both the Accura and T-scan Novus was excellent for measuring occlusal forces. In addition, both the Accura and T-scan Novus exhibited excellent repeatability.
Topics: Bite Force; Dental Articulators; Maxilla; Reproducibility of Results; Software
PubMed: 33250197
DOI: 10.1016/j.prosdent.2020.07.024 -
Journal of Prosthodontics : Official... Mar 2023To assess the influence of the number of teeth (2, 3, or 4) and location (molars, molar and premolar, or premolars and canines) of the bilateral virtual occlusal record...
Influence of the Number of Teeth and Location of the Virtual Occlusal Record on the Accuracy of the Maxillo-Mandibular Relationship Obtained by Using An Intraoral Scanner.
PURPOSE
To assess the influence of the number of teeth (2, 3, or 4) and location (molars, molar and premolar, or premolars and canines) of the bilateral virtual occlusal record on the accuracy of the virtual maxillo-mandibular relationship acquired by an intraoral scanner (IOS).
MATERIAL AND METHODS
Diagnostic casts mounted on a semi-adjustable articulator were obtained. Four markers were adhered on the facial surfaces of the first molars and canines. The mounted casts were digitized using an extraoral scanner. Maxillary and mandibular intraoral digital scans were obtained using an intraoral scanner (TRIOS 4). The maxillary and mandibular digital scans were duplicated 105 times and divided into 7 groups based on the number of teeth (2, 3, or 4) and location (molar, molar and premolar, or premolars and canines) of the bilateral virtual occlusal records (n = 15). The alignment of the scans was automatically performed after the acquisition of the corresponding occlusal records by the IOS program. Eight linear distances between the gauge balls were computed on the reference scan and on the 105 digital scans. The distances obtained on the reference scan were used to calculate the discrepancies with the distances obtained on each experimental scan. The Shapiro-Wilk test showed that the data was normally distributed. The trueness and precision data were analyzed using 2-way ANOVA followed by pairwise comparison Tukey tests (α = 0.05).
RESULTS
Two-way ANOVA showed that the number of teeth (p < 0.001) and the position of the virtual occlusal record (p < 0.001) were significant factors on the accuracy of the maxillo-mandibular relationship. Tukey test showed significant overall mean differences between the different groups tested: the 4-teeth group obtained the highest trueness, and the 2-teeth group showed the lowest trueness values (p < 0.001). Tukey test showed significant trueness differences between the virtual occlusal record locations. The 2-teeth record located more posteriorly obtained the lowest trueness. Significant differences in precision values were found among the subgroups tested (p < 0.001). The 2-teeth group obtained significantly more precision values than the 3- and 4-teeth groups. Additionally, there was a significant difference in precision values between the subgroup tested in which the first molar and second premolar location had the highest precision, while the first and second premolar's location obtained the lowest precision.
CONCLUSIONS
The number of teeth and the location of the bilateral virtual occlusal record influenced the accuracy of the virtual maxillo-mandibular relationship obtained by the intraoral scanner tested. The more teeth included in the bilateral virtual occlusal record, the higher the accuracy of the maxillo-mandibular relationship. Additionally, the more anteriorly located the virtual bilateral occlusal record involving 2 or 3 teeth was, the higher the accuracy mean value.
Topics: Imaging, Three-Dimensional; Models, Dental; Dental Impression Technique; Bicuspid; Maxilla; Computer-Aided Design
PubMed: 35448911
DOI: 10.1111/jopr.13526 -
BMC Oral Health Mar 2023Precise occlusal design of implant-supported fixed prostheses is difficult to achieve by the conventional wax-up method, often requiring chairside adjustments. The...
BACKGROUND
Precise occlusal design of implant-supported fixed prostheses is difficult to achieve by the conventional wax-up method, often requiring chairside adjustments. The computer-aided design (CAD) method is promising. This study aims to compare the occlusal contacts and clearance of posterior implant-supported single crowns designed by the CAD and conventional methods.
METHODS
Sample size calculation indicated fourteen samples per group. Two sets of type-IV plaster casts with a single implant analog inserted in the posterior teeth region were mounted as master casts in a mechanical articulator in maximal intercuspal position (MIP). Seven working cast sets were obtained from each master cast by a closed tray technique, and mounted in MIP. Two implant-supported single crowns were designed with an occlusal clearance to achieve light occlusal contact in each working cast set by CAD and conventional method, separately. For the CAD group, the crown was designed in digital models obtained by scanning the working casts. For the conventional group, wax-up of the crown was prepared on the working casts and scanned to generate a STL file. In the working and master casts, mean and minimum occlusal clearances in the designed occlusal contact area of the both finished prostheses were calculated using the occlusal clearance (OC) and occlusal record (OR) method. The prostheses' occlusion was evaluated in master casts.
RESULTS
For the evaluation in the working casts, both design methods had similar mean occlusal clearances by the OC method (195.4 ± 43.8 vs. 179.8 ± 41.8 μm; P = 0.300), while CAD group resulted in a significantly larger minimum occlusal clearance in the designed occlusal contact area (139.5 ± 52.3 vs. 99.8 ± 43.8 μm; P = 0.043). Both design methods had similar mean and minimum occlusal clearances by the OR method (P > 0.05). For the evaluation in the master casts, both design techniques had similar mean and minimum occlusal clearances, number and distribution of occlusal contacts, and lateral interference ratios (P > 0.05).
CONCLUSION
Occlusal contact and clearance of posterior implant-supported single crowns designed by the CAD method can be at least as good as those designed by the conventional wax-up method.
Topics: Humans; Crowns; Computer-Aided Design; Dental Occlusion; Research Design; Dental Impression Technique; Dental Prosthesis Design
PubMed: 36918877
DOI: 10.1186/s12903-023-02847-w -
Journal of Indian Prosthodontic Society 2021The Aim of the study was to evaluate the reproducibility of condylar inclination values obtained using three different interocclusal recording materials in Hanau... (Randomized Controlled Trial)
Randomized Controlled Trial
Comparative evaluation of condylar guidance obtained by three different interocclusal recording materials in a semi-adjustable articulator and digital panoramic radiographic images in dentate patients: An study.
AIM
The Aim of the study was to evaluate the reproducibility of condylar inclination values obtained using three different interocclusal recording materials in Hanau Wide-Vue semi-adjustable articulator and to compare those values of condylar inclination with panoramic radiographic images.
SETTINGS AND DESIGN
In Vivo Comparative study.
MATERIALS AND METHODS
The clinical trial was carried out in the Department of Prosthodontics, M. R Ambedkar Dental College and Hospital, Bengaluru. A total of 30 dentulous subjects aged between 20 and 40 years were selected, without any signs and symptoms of temporomandibular joint disorders. With the help of a custom-made protrusive guide, protrusive records for three materials were made. These records were used for programming the articulator and the respective horizontal condylar inclination (HCI) value, and panoramic radiographs were made. The values obtained were statistically analyzed.
STATISTICAL ANALYSIS USED
Independent t-test, multiple comparisons using Bonferroni method followed by Analysis of variances (ANOVA) were used.
RESULTS
Among each pair of groups there exists a significant difference, i.e., the mean condylar inclination (degree) was found to be statistically significant between wax and polyvinyl siloxane (P < 0.01) as well as between wax and polyether (P < 0.01). No significant difference was observed between polyvinyl siloxane and polyether (P > 0.05).
CONCLUSION
HCI values differed depending on the type of material employed. The study concluded that the protrusive condylar guidance angles obtained by panoramic radiograph can be used in programming the semi-adjustable articulator and among the materials polyether gave the highest Condylar Guidance values with less variability and wax gave lowest values with greater variation.
Topics: Adult; Dental Articulators; Humans; Jaw Relation Record; Mandibular Condyle; Radiography, Dental, Digital; Radiography, Panoramic; Reproducibility of Results; Young Adult
PubMed: 34810368
DOI: 10.4103/jips.jips_239_21 -
The Journal of Prosthetic Dentistry Oct 2022The Kois Dento-Facial Analyzer (KDFA) is used by clinicians to mount maxillary casts and to evaluate and treat patients. Limited information is available for... (Randomized Controlled Trial)
Randomized Controlled Trial
STATEMENT OF PROBLEM
The Kois Dento-Facial Analyzer (KDFA) is used by clinicians to mount maxillary casts and to evaluate and treat patients. Limited information is available for understanding whether the KDFA should be considered as an alternative to an arbitrary facebow.
PURPOSE
The purpose of this clinical study was to evaluate and compare maxillary casts mounted by using the KDFA with casts mounted by using the Panadent Pana-Mount Facebow (PMF) and a kinematic axis (KA) facebow.
MATERIAL AND METHODS
Fifteen participants were enrolled in the study. Three maxillary impressions were made of each study participant. One cast from each study participant was mounted on an articulator by means of the KDFA, PMF, and KA. A standardized photograph of each mounting was made, and the condylar center-incisor distance and the occlusal and incisal plane angles were measured. A randomized complete block design analysis of variance (RCBD) (α=.05) and post hoc tests (Tukey-Kramer HSD) were used to evaluate the occlusal and incisal plane angles and the condylar center-incisor distance.
RESULTS
Compared with the occlusal plane angle (OPA), the KDFA mounted the maxillary cast at an angle that was statistically lower than those of PMF and KA (P<.001). The KDFA and the PMF condylar center-incisor distances were both significantly greater than that of KA (P=.01). No differences were found between the incisal plane angle (IPA) on maxillary casts mounted with the KDFA, KA, or PMF (P=.16).
CONCLUSIONS
The KDFA and PMF mounted the maxillary casts in a position that was farther from the axis when compared with the KA mounted casts. The KDFA resulted in a lower articulator OPA compared with both PMF and KA. No difference was found between the IPAs of the KDFA, PMF, and KA.
Topics: Humans; Biomechanical Phenomena; Dental Articulators; Dental Occlusion; Jaw Relation Record; Maxilla
PubMed: 33736862
DOI: 10.1016/j.prosdent.2020.12.023 -
The European Journal of Prosthodontics... Mar 2023To determine whether the use of single or combined mechanical and virtual articulators, as well as facebows, jaw motion trackers, face scanners, and related devices,...
AIMS
To determine whether the use of single or combined mechanical and virtual articulators, as well as facebows, jaw motion trackers, face scanners, and related devices, actually improve the efficacy of the prosthesis obtained in terms of lifespan and patient-related outcomes. To coin the terms Analogic and Digital Virtual Patients (AVP and DVP) as an attempt to analyze, clarify and synthesize terminology and workflows related to previously so-called devices.
MATERIALS AND METHODS
A scoping review was accomplished involving different databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-ScR) checklist and JBI guidance were followed to extract data regarding the Population, Context and Concept established.
RESULTS
Available literature on the efficacy of using devices and techniques related to both AVP and DVP workflows showed arguable study designs, great heterogeneity, and questionable quality.
CONCLUSIONS
The terms AVP and DVP have been coined as a first step to clarify and simplify concepts and workflows related to the use of both mechanical and virtual articulators, as well as facebows, or facial and intraoral scanners, among others. This scoping review cannot claim that an AVP approach leads to more effective and efficient prosthetic restorations.
PubMed: 36927617
DOI: 10.1922/EJPRD_2485Pradies17