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Annals of African Medicine 2023During complete denture fabrication making Interocclusal records plays an integral role to obtain the condylar guidance value. The study was conducted to compare the...
BACKGROUND AND PURPOSE
During complete denture fabrication making Interocclusal records plays an integral role to obtain the condylar guidance value. The study was conducted to compare the protrusive condylar guidance registration by two interocclusal recording materials-Quick setting plaster and Luxabite®(bisacrylic composite) in semi adjustable articulator for completely edentulous patients.
METHODOLOGY
Maxillary and Mandibular casts of the completely edentulous patients were mounted in Hanau®Wide Vue articulator. The Quick setting plaster and Luxabite®(bisacrylic composite) was used as interocclusal recording materials to program the protrusive condylar guidance angles in the articulators.
RESULTS
The protrusive condylar guidance values registered in the articulator for the different interocclusal records were tabulated and statistically analyzed.. The mean protrusive condylar guidance values registered in the articulator was compared with two parameters obtained from the radiographic tracings -- the protrusive condylar path angle obtained with Quick setting plaster and Luxabite with the inclination of articular eminence to the Frankfort horizontal plane.
CONCLUSION
From the study it was concluded that the Luxabite®(bisacrylic composite) material demonstrated better reproducibility of protrusive condylar guidance registration.than the Quick setting plaster.
Topics: Humans; Mandibular Condyle; Jaw Relation Record; Reproducibility of Results; Mandible; Resin Cements
PubMed: 37417019
DOI: 10.4103/aam.aam_70_22 -
Contemporary Clinical Dentistry 2022The aim of the study was to determine the effect of different anterior reference points during facebow transfer, on sagittal inclination of occlusal plane (SIOP) and...
AIM
The aim of the study was to determine the effect of different anterior reference points during facebow transfer, on sagittal inclination of occlusal plane (SIOP) and horizontal condylar guidance (HCG) values obtained on arcon and nonarcon articulators.
MATERIALS AND METHODS
Facebow records of 25 participants were made and transferred to Hanau Wide-Vue (WV) and Hanau H2 (H2) articulators using conventional indirect transfer (CIT), superior annular groove (SAG), and inferior annular groove (IAG) as anterior reference points. Maxillary casts were mounted on each articulator followed by mandibular mountings. Protrusive interocclusal record was used to determine HCG, and SIOP was measured as an angle between the occlusal plane of mounted maxillary cast and upper member of the articulator. Both, HCG and SIOP were measured on a digital lateral cephalogram and the values obtained were compared with previously determined values from both the articulators. Intergroup comparison was done by analysis of variance and pair-wise comparison by Tukey test.
RESULTS
Values of SIOP significantly ( = 0.00) changed on both the articulators when CIT, SAG, and IAG were the anterior reference points. The ratio of SIOP and HCG on both articulators was comparable to that of the cephalogram for CIT, IAG, but it was substantially low for SAG.
CONCLUSIONS
The variation of anterior reference point changes the value of SIOP recorded on Hanau WV and H2 articulators; however, it had no effect on HCG values recorded on both the articulators. The angle between SIOP and HCG changed with variations in superior-inferior position of the mountings on both articulators.
PubMed: 36213845
DOI: 10.4103/ccd.ccd_1035_20 -
Dental Research Journal 2023Horizontal condylar guidance (HCG) is registered by protrusive interocclusal records but in nonarcon articulators, these records can affect the accuracy. The present...
BACKGROUND
Horizontal condylar guidance (HCG) is registered by protrusive interocclusal records but in nonarcon articulators, these records can affect the accuracy. The present study aimed to evaluate the effect of a novel rotation coordinating device (RCD) on condylar guidance setting with protrusive interocclusal records.
MATERIALS AND METHODS
The study was designed as a comparative investigation. Stone maxillary and mandibular casts were mounted on a fully adjustable instrument as the patient. Duplicate casts were mounted on an arcon and a nonarcon articulator with corresponding face bow records and in maximum intercuspation relation. Five different condylar guidance inclinations for both sides (20°, 30°, 40°, 50°, and 60°) were set on the fully adjustable instrument and 16 protrusive interocclusal records were established at each setting. HCG was set for arcon, nonarcon articulators, and nonarcon articulators with RCD. Data were analyzed using one-sample -test to compare with actual HCG and one-way analysis of variance ( =0.05).
RESULTS
Mean HCG for studied articulators was 35.40 for arcon, 30.31 for nonarcon without RCD, and 35.61 for nonarcon with RCD which were significantly different from actual HCG ( < 0.05). HCG of the nonarcon with RCD showed no significant difference with arcon articulator ( = 0.71) while both were significantly different from nonarcon without RCD ( < 0.001).
CONCLUSION
"The RCD" compensates the condylar guidance inclination difference between arcon and nonarcon articulators. The device precisely transfers the hinge movement of the upper member of the articulator to the condylar track.
PubMed: 38020259
DOI: No ID Found -
Materials (Basel, Switzerland) May 2021The purpose of this in vitro study was to compare the accuracy of the proximal and occlusal contacts of single implant crowns fabricated with four data capture methods....
The purpose of this in vitro study was to compare the accuracy of the proximal and occlusal contacts of single implant crowns fabricated with four data capture methods. The resin models were mounted on an articulator, digitized using a laboratory scanner, and saved as a standard tessellation language (STL) file to serve as the master reference model (MRM). Two different intraoral scan body (ISB) systems were evaluated: polyetheretherketone (PEEK) short scan body (SSB) and PEEK long scan body (LSB) ( = 12). The digital impressions (SSB and LSB) were acquired using an intraoral scanner with ISB. Two different conventional techniques were also evaluated: PEEK short scan body with coping plastic cap (CPC) and pick-up coping (PUC) ( = 12). The implant impressions (CPC and PUC) were recorded using a conventional impression technique. The crown and abutment were fabricated with a milling machine and then placed on the resin model and scanned using a laboratory scanner. The scanned files were saved as STL files to serve as test datasets. The MRM and test datasets were superimposed, and the mesial, distal, and occlusal distances were calculated using a 3D inspection software and statistically analyzed using the Kruskal-Wallis H test (α = 0.05). The direct data capture group had more accurate contact points on the three surfaces, with mesial contact of 64.7 (12.8) µm followed by distal contact of 65.4 (15) µm and occlusal contact of 147 (35.8) µm in the SSB group, and mesial contact of 84.9 (22.6) µm followed by distal contact of 69.5 (19.2) µm and occlusal contact of 115.9 (27.7) µm in the LSB group ( < 0.001). The direct data capture groups are closer to the ideal proximal and occlusal contacts for single implant crowns than the indirect data capture groups. There was no difference in the accuracy between the two types of scan body (SSB and LSB).
PubMed: 34073329
DOI: 10.3390/ma14112843 -
Acta Stomatologica Croatica Sep 2019Programming of joint mechanism/parameters (sagittal condylar inclination and Bennett angle) of adjustable dental articulators is a prerequisite for performing positions...
OBJECTIVES
Programming of joint mechanism/parameters (sagittal condylar inclination and Bennett angle) of adjustable dental articulators is a prerequisite for performing positions and movements of the mandible. The aim of the study was to test significant differences between the two methods (wax eccentric records and Arcus Digma device) of measuring these joint parameters by using three different dental articulators (SAM 3, Protar 7; and Artex CR).
MATERIALS AND METHODS
Thirty asymptomatic younger (age 25.7 ± 2.9 years) subjects (dental medicine students) divided by gender, with normal occlusion (Angle class I) participated in the study. After taking anatomical impressions of both dental arches, master casts were made of hard dental plaster for each subject. The values of the left and right sagittal condylar inclination and Bennett angle by the two methods of wax eccentric protrusive and lateral records and Arcus Digma device were measured for the purpose of programming the mentioned joint parameters in three different articulator systems.
RESULTS
The average values of the measured parameters of sagittal condylar inclination and Bennett angle of wax eccentric records were higher (ranging from 5ºto 10º) in relation to the values measured by Arcus Digma device. Statistically significant differences found between the measured joint parameters (p <0.025) were influenced by the articulator system design and measurement methods (t-test for dependent samples and MANOVA).
CONCLUSION
The use of Arcus Digma device should be considered reliable and valid for individualized programming of dental articulators, rather than the use of wax eccentric records.
PubMed: 31749453
DOI: 10.15644/asc53/3/3 -
Journal of Clinical and Experimental... Jan 2018The search for the ideal, healthy and reproducible position of the condyles is of utmost importance for dental diagnosis and treatment. Thus, the objective of this...
BACKGROUND
The search for the ideal, healthy and reproducible position of the condyles is of utmost importance for dental diagnosis and treatment. Thus, the objective of this laboratory cross-sectional study was to verify the relationship between the posterior joint space and the mandibular lateral movements.
MATERIAL AND METHODS
Dental casts from 15 women and 15 men with normal mastication, 28 natural teeth and no history of temporomandibular disorders or pain, were fabricated and mounted on a fully adjustable articulator. From the maximum intercuspal position, condylar displacement was evaluated and measured on the working and nonworking sides during mandibular lateral movement, both to the right and left sides.
RESULTS
The correlation between the measures of interest was assessed with the Pearson correlation coefficient (α=.05). Condylar displacement on the working side and nonworking side condyle was 0.88±0.71 mm and 3.57±1.11 mm (right mandibular lateral movement); and 0.91±0.58 mm and 3.51±0.78mm (left mandibular lateral movement), respectively. No significant correlation in the condylar displacement between the working side condyles on the right and on the left sides was observed (r=.22; P=.248). The condylar poles of the articulator moved posteriorly, simulating the functional movements of the mandible during mastication. In all cases, condylar displacement during mandibular lateral movement both to the right and left occurred posteriorly on the working side condyle.
CONCLUSIONS
The condylar poles of the articulator moved posteriorly simulating the functional movements of the mandible during mastication. Moreover, left and right working condyles may require slightly different spaces to function, suggesting minor anatomical asymmetries. Mastication, dental occlusion, prosthodontics.
PubMed: 29670717
DOI: 10.4317/jced.54168 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Apr 2024This clinical study aimed to assess the trueness of three intraoral scanners for the recor-ding of the maximal intercuspal position (MIP) to provide a reference for...
OBJECTIVES
This clinical study aimed to assess the trueness of three intraoral scanners for the recor-ding of the maximal intercuspal position (MIP) to provide a reference for clinical practice.
METHODS
Ten participants with good occlusal relationship and healthy temporomandibular joint were recruited. For the control group, facebow transferring procedures were performed, and bite registrations at the MIP were used to transfer maxillary and mandibular casts to a mechanical articulator, which were then scanned with a laboratory scanner to obtain digital cast data. For the experimental groups, three intraoral scanners (Trios 3, Carestream 3600, and Aoralscan 3) were used to obtain digital casts of the participants at the MIP following the scanning workflows endorsed by the corresponding manufacturers. Subsequently, measurement points were marked on the control group's digital casts at the central incisors, canines, and first molars, and corresponding distances between these points on the maxillary and mandibular casts were measured to calculate the sum of measured distances (D). Distances between measurement points in the incisor (D), canine (D), and first molar (D) regions were also calculated. The control group's maxillary and mandibular digital casts with the added measurement points were aligned with the experimental group's casts, and D, D, D, and D values of the aligned control casts were determined. Statistical analysis was performed on D, D, D, and D obtained from both the control and experimental groups to evaluate the trueness of the three intraoral scanners for the recording of MIP.
RESULTS
In the control group, D, D, D, and D values were (39.58±6.40), (13.64±3.58), (14.91±2.85), and (11.03±1.56) mm. The Trios 3 group had values of (38.99±6.60), (13.42±3.66), (14.55±2.87), and (11.03±1.69) mm. The Carestream 3600 group showed values of (38.57±6.36), (13.56±3.68), (14.45±2.85), and (10.55±1.41) mm, while the Aoralscan 3 group had values of (38.16±5.69), (13.03±3.54), (14.23±2.59), and (10.90±1.54) mm. Analysis of variance revealed no statistically significant differences between the experimental and control groups for overall deviation D (=0.96), as well as local deviations D (=0.98), D (=0.96), and D (=0.89).
CONCLUSIONS
With standardized scanning protocols, the three intraoral scanners demonstrated comparable trueness to traditional methods in recording MIP, fulfilling clinical requirements.
Topics: Humans; Molar; Incisor; Mandible; Maxilla; Computer-Aided Design; Imaging, Three-Dimensional; Dental Impression Technique
PubMed: 38597082
DOI: 10.7518/hxkq.2024.2023277 -
Indian Journal of Dental Research :... 2012The etiopathogenesis of temporomandibular joint (TMJ) disorders has been attributed to multiple factors and, while the importance of centric relation (CR) has been... (Comparative Study)
Comparative Study
CONTEXT
The etiopathogenesis of temporomandibular joint (TMJ) disorders has been attributed to multiple factors and, while the importance of centric relation (CR) has been acknowledged in dental literature, the role of condylar position and CR-CO (CO-centric occlusion) discrepancy in TMJ dysfunction (TMD) has been a source of controversy.
AIM
To establish the relationship between condyle position and TMD.
SETTING AND DESIGN
This was a case-control study to evaluate condylar displacement and interarch CR-CO discrepancy in symptomatic subjects (with TMD) and compare them with asymptomatic subjects.
MATERIALS AND METHODS
Forty subjects were screened for TMD based on Helkimo index and grouped into asymptomatic and symptomatic groups. CR was registered using the modified Roth power centric bite registration after neuromuscular deprogramming. Models thus mounted on an Advanced Dental Design (AD2) articulator were evaluated for interarch CR-CO discrepancy. The condylar position discrepancy was recorded on a device MCD (measured condylar deviation).
STATISTICAL ANALYSIS
The Student's t test was used to test statistical significance. The paired t test and the unpaired t test were used for comparing results within and between the groups. Pearson correlation coefficient was used to find out the correlation between MCD measurements and dental three-dimensional (3D) model analysis measurements. The Chi-square test was used to evaluate the qualitative data.
RESULTS
The average vertical and horizontal condylar displacements were significantly greater in the symptomatic group than in the asymptomatic group. There were significant deviations at the level of the occlusion in both groups.
CONCLUSION
Condyle position may play a significant role in the etiopathogenesis of TMJ disorders.
Topics: Adolescent; Adult; Case-Control Studies; Centric Relation; Dental Arch; Dental Articulators; Dental Occlusion, Centric; Humans; Imaging, Three-Dimensional; Jaw Relation Record; Mandibular Condyle; Models, Dental; Overbite; Photography, Dental; Radiography, Panoramic; Temporomandibular Joint Disorders; Tomography, X-Ray; Young Adult
PubMed: 22842268
DOI: 10.4103/0970-9290.99060 -
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 Sep 2023Although different digital occlusal analyzers have been marketed, comparative studies are lacking.
STATEMENT OF PROBLEM
Although different digital occlusal analyzers have been marketed, comparative studies are lacking.
PURPOSE
The purpose of this in vitro study was to compare the repeatability and reproducibility of 2 different digital occlusal analyzers (T-Scan and OccluSense) for measuring the right- and left-side balance of occlusal contact forces.
MATERIAL AND METHODS
The repeatability and reproducibility of the 2 digital occlusal analyzers for measuring the balance of occlusal contact forces were determined and compared by using the Gauge Repeatability and Reproducibility tests based on the International Organization for Standardization (ISO), ISO 5725-2 and ISO 5725-3 standards. Ten different dental casts were mounted in the maximum intercuspation position on a semi-adjustable articulator. Then, the balance of occlusal contact forces in each of the 10 articulated dental casts was measured 24 times with each of the 2 digital occlusal analyzers. In addition, as the OccluSense, unlike the T-Scan, does not have a centering support for the piezoelectric film sensor, measurements with it were performed without and with a custom-designed and manufactured centering support. Finally, the repeatability and reproducibility of both digital occlusal analyzers were determined and compared using the Gauge Repeatability and Reproducibility tests.
RESULTS
The repeatability and reproducibility tests revealed that only 0.8% of the variance of the measurements obtained with the T-Scan was due to repeatability and reproducibility (0.4% repeatability, 0.4% reproducibility). In contrast, 12% of the variance of the measurements obtained with the OccluSense was due to repeatability and reproducibility (2.2% repeatability, 9.8% reproducibility). However, when using OccluSense with the centering support, the variance decreased to 6.4% (2.8% repeatability, 3.6% reproducibility). According to the Automotive Industry Action Group classification, the repeatability and reproducibility of the T-Scan were good, those of the OccluSense poor, and those of the OccluSense with the centering support medium.
CONCLUSIONS
The repeatability and reproducibility of the T-Scan were significantly better than those of the OccluSense for measuring the balance of occlusal contact forces. Furthermore, the repeatability and reproducibility of the OccluSense were significantly improved when used with a device to center the piezoelectric film sensor between the incisors. Nevertheless, the repeatability and reproducibility of the T-Scan were better.
PubMed: 37661548
DOI: 10.1016/j.prosdent.2023.07.026