Search

A new and simple articulator classification has been proposed which includes both mechanical and virtual articulators to meet with the modern day dental practice that has shown a gradual shift toward digital technology and workflow.

Objectives: The literature review aimed to compile and summarize the results of research relating to the recordings of condylar displacements obtained with extraoral devices, to guide clinicians to set dental (virtual) articulator parameters. The metaanalysis was undertaken to assess the sagittal condylar inclination (SCI) and transversal condylar inclination (TCI, also known as Bennett angle) values according to horizontal reference planes, movement studied, and patient characteristics: dental status, interocclusal relationship, skeletal pattern, and signs and symptoms of temporomandibular disorders (TMD). Data sources: A bibliographic search was conducted in the three following electronic databases: MEDLINE, EMBASE, and Cochrane Library and Best Evidence. The review was restricted to trials involving participants meeting the following criteria: (1) adult, (2) no previous surgery in the temporomandibular region, and (3) no serious comorbidity conditions. Descriptive statistics were calculated for all study groups and were compared by applying a one-way ANOVA. Conclusion: All 20 articles selected corresponded to a total of 933 subjects evaluated. The recording devices and horizontal reference planes had a significant impact on the SCI values. Age, dental status, and the presence of symptoms and signs of TMD in subjects had no influence on SCI values, unlike Angle class II, division 2, the class II sagittal pattern, or the increased vertical skeletal pattern SCI parameters (P < .05). The mean TCI value was 8 degrees and was independent of individual patient characteristics and the extraoral recording device used. For accurate kinematic simulation, the patient's personal plane of reference must be transferred to the system. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new and simple articulator classification has been proposed which includes both mechanical and virtual articulators to meet with the modern day dental practice that has shown a gradual shift toward digital technology and workflow. [ABSTRACT FROM AUTHOR]

Copyright of Meandros Medical & Dental Journal is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For full‐mouth rehabilitation of worn dentition, "diagnostic" interim restorations are required to reestablish the interocclusal relationship. It is important but challenging to transfer the interocclusal relationship and to map the basic form and contour of interim restorations to the final restorations. Alignment of interim restorations and working casts is difficult when using digital workflows because of a lack of consistent hard tissue reference points. The digital workflow presented in this study used a "3‐point sectional‐cast digital cross‐mounting method" to transfer the interocclusal relationship during full‐mouth rehabilitation. An intermediate cast was made with three interim restorations: one on an incisor and two on molars. The interocclusal relationship and occlusal morphologies of the diagnostic interim prostheses were transferred and aligned to working casts using the 3‐point sectional casts. [ABSTRACT FROM AUTHOR]

Background: Available knowledge about malocclusion and cephalometric variables and their connection with an increased risk of condylar displacement (CD) is scarce. This article aims to present current information on the relationship between centric relation-maximum intercuspal position discrepancies and maxillofacial morphology and malocclusion in patients seeking orthodontic treatment as well as to identify those who require expanded diagnostic evaluation for this disorder. Methods: This review analyzed the PubMed, Cochrane Library, Web of Science, and Scopus electronic databases up to February 2022. Keywords and additional manual searches were performed. Literature selection was based the PRISMA-ScR checklist. The JBI Critical Appraisal Tool assessed the methodological quality of included studies. Results: The databases search provided 2321 studies. A total of 10 studies were included in this review after eligibility criteria and JBI assessment. This review was separated into five parts that evaluated CD correlations depending on the following: maxillofacial structure in different vertical and sagittal skeletal patterns, vertical, horizontal, and transverse malocclusions. Conclusions: A hyperdivergent facial skeletal structure is a risk factor for increased CD, particularly in the vertical dimension. The condylar processes are usually displaced in a posteroinferior direction. Further studies are warranted to elucidate the relationship among remaining skeletal and dental malocclusions and the occurrence of CD. [ABSTRACT FROM AUTHOR]

Objective: Interchangeable articulators are crucial for a precise clinical outcome. Lack of interchangeability will affect the accuracy of the occlusion of prosthetic restorations. The objective of this study was to evaluate the interchangeability of KaVo PROTARevo articulators. Method and Materials: KaVo PROTARevo semi-adjustable articulators in routine use were employed. Identical casts were transferred among the articulators and the distance between casts was measured using digital photos of sagittal and frontal aspects of each articulator by two independent examiners. Interchangeability was assessed and analyzed by designated software. Results: Inter-examiner reliability was found to be high. Of 231 possible pairs of articulators only 27 pairs were found to be interchangeable (less than 166 µm in all measured dimensions), and of the other 204 pairs of articulators at least one of the dimensions measured was larger than 166 µm. Conclusion: The majority of articulators tested did not pass the 166-µm criterion to establish them as interchangeable. Therefore, in order to maintain accuracy while producing restorations, it is advisable to use the same articulator throughout the entire process, both at the clinic and in the dental laboratory. [ABSTRACT FROM AUTHOR]

Featured Application: Better surgical planning of the mandibular angle region. The surgical correction of dento-maxillofacial deformities for aesthetic reasons is increasingly required. In order to obtain the results that our patients expect, it is necessary to very thoroughly evaluate every aesthetic detail of the face, because an optimal result comes from the correction of all parameters. The region of the mandibular angles is very important in determining the final aesthetics but is at the same time difficult to predict. Traditional programming based on model surgery is inadequate in this regard compared to that based on CT (Computed Tomography) reconstruction. The authors explain the reasons for this and demonstrate the problems by reporting a typical clinical case. [ABSTRACT FROM AUTHOR]

A technique for the application of a virtual articulation system in 3-dimensional digital smile design (DSD) during esthetic restoration is described. To acquire stable occlusion and a smooth jaw movement pattern without premature contacts or interference, a digital facebow and a virtual articulator were used to collect and analyze a patient's occlusal data and jaw movement information. The original pattern of occlusal contacts and jaw movements were diagnosed as stable and copied to the digital design of the new prostheses. Preparation of the abutments, crown lengthening surgery, and definitive crown fabrication and cementation were performed according to the design. After 9 months, the occlusion remained stable, and the patient was satisfied with the outcome., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objective: To explore the method of obtaining the key parameters of the average value articulator in healthy people based on mandibular movement trajectory data, with a view to providing a reference for the clinical application of the average value articulator. Methods: One hundred healthy volunteers (42 males and 58 females) with individual normal occlusion, aged 18-55 years old, who met the inclusion criteria were recruited from Beijing, and their mandibular movement trajectory data were collected. The left and right sagittal condylar inclination(SCI) and transversal condylar inclination(TCI) were obtained from the values of the articulator parameters which were generated in the mandibular movement analysis system.The SCI and TCI were grouped by gender and calculated separately for the two groups and the overall sample; the gender differences in the two parameters and the differences between the mean values of the two parameters and the average value articulator empirical values (35° for SCI and 15° for TCI) for the overall sample were compared. Results: The differences between SCI (35.8°±7.4°) and TCI [11.2° (11.3°)] in males and the corresponding parameters [35.6°±8.3° and 10.8° (9.5°), respectively] in females were not statistically significant ( t =0.10, P =0.922; Z =-0.60, P =0.552); the overall sample SCI (35.7°±7.9°) did not differ statistically from the average value articulator empirical value ( t =1.23, P =0.221), and the overall sample TCI [10.9° (10.3°)] was significantly smaller than the average value articulator empirical value ( W =5 825.00, P <0.001). Conclusions: The mandibular movement trajectory data of 100 adults with individual normal occlusion in this study shows that the gender factor does not affect the setting of the key parameters of the average value articulator, the SCI of the average value articulator empirical values is appropriate, and the TCI has the possibility of being on the large side. In the clinical use of the articulator to assist in the design of restorations, the parameter values should be rationally adjusted according to the actual situation of the patient's dentition and mandibular movement.

Objectives: The purposes of this study were to classify the described digital facebow techniques for transferring the maxillary cast into the semi-adjustable virtual articulator based on the digital data acquisition technology used and to review the reported accuracy values of the different digital facebow methods described., Overview: Digital data acquisition technologies, including digital photographs, facial scanners, cone beam computed tomography (CBCT) imaging, and jaw tracking systems, can be used to transfer the maxillary cast into the virtual articulator. The reported techniques are reviewed, as well as the reported accuracy values of the different digital facebow methods., Conclusions: Digital photographs can be used to transfer the maxillary cast into the virtual articulator using the true horizontal reference plane, but limited studies have assessed the accuracy of this method. Facial scanning and CBCT techniques can be used to transfer the maxillary cast into the virtual articulator, in which the most frequently selected references planes are the Frankfort horizontal, axis orbital, and true horizontal planes. Studies analyzing the accuracy of the maxillary cast transfer by using facial scanning and CBCT techniques are restricted. Lastly, optical jaw trackers can be selected for transferring the maxillary cast into the virtual articulator by using the axis orbital or true horizontal planes, yet the accuracy of these systems is unknown., Clinical Implications: Digital data acquisition technologies, including digital photographs, facial scanning methods, CBCTs, and optical jaw tracking systems, can be used to transfer the maxillary cast into the virtual articulator. Studies are needed to assess the accuracy of these digital data acquisition technologies for transferring the maxillary cast into the virtual articulator., (© 2024 Wiley Periodicals LLC.)

Objectives: This study aimed to assess the influence of the location and distribution of short-span scans, serving as intermediate registration data, on the trueness of digitally transferring the maxillomandibular relationship in full-mouth rehabilitation., Methods: Maxillary and mandibular complete-arch preparation casts mounted on an articulator were scanned, with and without interim restorations, using an intraoral scanner. Four types of short-span scans-right anterior, left anterior, right posterior, and left posterior-were captured from maxillary and mandibular casts. Each scan comprised two prepared teeth and two crowned teeth arranged alternately. These short-span scans served as intermediate data and were cross-registered with complete-arch interim restorations and preparation casts to transfer the maxillomandibular relationship. Based on the number (1 or 2), location (anterior or posterior), and distribution (unilateral or bilateral) of short-span scans, they were categorized into six groups. Trueness was assessed by evaluating the mandibular 3-dimensional (3D), spatial distance, angle, and linear distance deviations between the test and reference scans., Results: Significant differences in the trueness of digital cross-mounting were observed among the six groups (P < .05). The group registering the bilateral posterior areas exhibited the smallest 3D, spatial distance, angle, and linear distance deviations, whereas the group registering one anterior area showed the largest deviations., Conclusion: The number, location, and distribution of the registered short-span scans significantly affected the trueness of transferring the maxillomandibular relationship. A posterior short-span scan had higher trueness than an anterior scan. The symmetrical distribution of the two registered larger short-span scans over the cross-arch enhanced the registration trueness., Clinical Significance: Digital cross-mounting in full-mouth rehabilitation using short-span scans enhances transfer accuracy, improves patient comfort, and increases chairside efficiency., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Statement of Problem: Alternatives to the bilateral interocclusal registration scanning technique to improve virtual articulation have not been fully investigated., Purpose: The purpose of this in vitro study was to compare the accuracy of virtually articulating digital casts by using bilateral interocclusal registration scans versus a complete arch interocclusal scan., Material and Methods: A set of maxillary and mandibular reference casts were hand-articulated and mounted on an articulator. The mounted reference casts were scanned, and the maxillomandibular relationship record was scanned 15 times using 2 different scanning techniques, the bilateral interocclusal registration scan (BIRS) and complete arch interocclusal registration scan (CIRS), with an intraoral scanner. The generated files were transferred to a virtual articulator, and each set of scanned casts was articulated using BIRS and CIRS. The virtually articulated casts were saved as a set and transferred to a 3-dimensional (3D) analysis program. The scanned casts were set in the same coordinate system as the reference cast and overlaid on top of the reference cast for analysis. Two anterior and 2 posterior points were selected to determine points of comparison between the reference cast and test casts virtually articulated with BIRS and CIRS. The mean discrepancy between the 2 test groups and the anterior and posterior mean discrepancy within each group were tested for significance by using the Mann-Whitney U test (α=.05)., Results: A significant difference was found between the virtual articulation accuracy of BIRS and CIRS (P<.001). The mean deviation for BIRS was 0.053 ±0.051 mm and that for CIRS was 0.265 ±0.241 mm. Furthermore, significant differences were found between the anterior and posterior deviations in both BIRS (P=.020) and CIRS (P<.001). The mean deviation for BIRS was 0.034 ±0.026 mm in the anterior and 0.073 ±0.062 mm in the posterior. The mean deviation for CIRS was 0.146 ±0.108 mm anteriorly and 0.385 ±0.277 mm posteriorly., Conclusions: BIRS was more accurate than CIRS for virtual articulation. Moreover, the alignment accuracy of anterior and posterior sites for both BIRS and CIRS exhibited significant differences, with the anterior alignment exhibiting better accuracy in relation to the reference cast., (Copyright © 2023 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: This in vitro study was formulated to clarify how mandibular partial edentulous distal extension involving three missing teeth affects the virtual occlusal record (VOR) accuracy, in terms of both trueness and precision, when using two different intraoral scanners (IOSs) - the Primescan (PS) and Trios 4 (TR) scanners., Methods: A typodont model missing the left mandibular second premolar, first molar, and second molar as well as the right mandibular first molar was mounted on a semi-adjustable articulator. Four implants were placed at the sites of the missing mandibular teeth. Six pairs of stainless steel markers (diameter: 0.5 mm) were affixed to the maxillary and mandibular casts in the buccal gingiva adjacent to the implants and on the facial surfaces of teeth as reference positions for measurements. The model was digitized with an inEox X5 laboratory scanner to create a reference dataset. Intraoral scans were performed with the PS and TR scanners, with each scan duplicated 10 times to generate 20 paired IOS files. Automatic VOR generation followed the bilateral buccal scan protocol, divided into PS and TR groups (n = 10). Six subgroups of linear distances between interarch markers were assessed with Geomagic Control software, comparing deviations from the reference scan. Data normality was confirmed with the Shapiro-Wilk test. Trueness was evaluated with two-way ANOVAs and pairwise comparisons performed with Tukey's test, whereas precision was assessed with the Levene test (α=0.05)., Results: The mean linear deviation (Δd) and standard deviation (SD) of VOR were both significantly affected by marker position (P < 0.001), and a significant position × scanner interaction was detected (P < 0.001). Negative mean deviations were observed for the distally extended edentulous areas in both groups. PS scans exhibited trueness that was significantly better than that for TR scans in the D16-46, D13-43, D23-33, and D27-37 subgroups (P < 0.05), whereas there were no significant differences in the D25-35 or D26-36 subgroups. PS scanning was associated with significantly better precision than TR scanning (P < 0.001), and worse precision was observed at D27-37 for both tested IOSs., Conclusions: Mandibular partial edentulous distal extension can significantly affect VOR accuracy. The type of IOS could also affect VOR accuracy depending on the area being scanned, with better overall performance observed for the Primescan device as compared to the Trios 4 scanner. Both of these IOSs tended to underestimate VOR occlusal dimensions in mandibular distally extended edentulous areas., Clinical Significance: Mandibular distal edentulous areas can contribute to occlusal dimensions that are underestimated in digital workflows, which may result in infraocclusal discrepancies that arise when performing restorations. IOSs and VOR scanning protocols should thus be carefully considered in order to minimize these risks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Statement of Problem: Some contemporary articulator systems claim to be highly precise in their interchangeability, with tolerances below 10 μm in vertical error; however, the claims have not been independently verified., Purpose: The purpose of this study was to investigate the interchangeability of calibrated semiadjustable articulators in service over time., Material and Methods: A calibrated mounting articulator served as the master articulator, while the test groups were used articulators with a minimum of 1-year use by predoctoral dental students (n=10); used articulators with a minimum of 1-year use by prosthodontic residents (n=10); and new articulators (n=10). One set of mounted maxillary and mandibular master models was positioned in the master and test articulators. High-precision reference markers on the master models were used to determine interarch 3D distance distortions (dR R , dR C , and dR L ), interocclusal 3D distance distortion (dR M ), interocclusal 2D distance distortions (dx M , dy M , and dz M ), and interocclusal angular distortion (dθ M ) relative to the master articulator. All measurements were conducted three times using a coordinate measuring machine and then averaged to derive the final data set., Results: For interarch 3D distance distortion, the mean dR R ranged from 4.6 ±21.6 μm for new articulators to 56.3 ±47.6 μm for articulators used by prosthodontic residents; mean dR C ranged from 65 ±48.6 μm for new articulators to 119.0 ±58.8 μm for articulators used by prosthodontic residents; and mean dR L ranged from 12.7 ±39.7 μm for articulators used by prosthodontic residents to 62.8 ±75.2 μm for new articulators. For interocclusal 3D distance distortion, the mean dR M ranged from 21.5 ±49.8 μm for new articulators to 68.6 ±64.9 μm for articulators used by predoctoral dental students. For the 2D distance distortions, the mean dx M ranged from -17.9 ±43.4 μm for articulators used by predoctoral dental students to -61.9 ±48.3 μm for articulators used by prosthodontic residents; mean dy M ranged from 18.1 ±59.4 μm for new articulators to 69.3 ±115.1 μm for articulators used by prosthodontic residents; and mean dz M ranged from 29.5 ±20.2 μm for new articulators to 70.1 ±37.8 μm for articulators used by prosthodontic residents. Mean dθ M ranged from -0.018 ±0.289 degree for new articulators to 0.141 ±0.267 degree for articulators used by prosthodontic residents. One-way ANOVA by articulator type revealed statistically significant differences among the test groups for dR R (P=.007) and dz M (P=.011) only, where articulators used by prosthodontic residents fared significantly poorer than the other test groups., Conclusions: The new and used articulators tested did not fulfill the manufacturer's claim of accuracy of up to 10 μm in the vertical dimension. Up to 1 year of time in service, none of the investigated test groups fulfilled the criterion for articulator interchangeability, even if the more lenient threshold of 166 μm were accepted., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Statement of Problem: The conventional diagnostic mounting procedure in completely edentulous patients is time-consuming and increases the laboratory workload. Alternatives like optical scanners and jaw tracking devices have been documented but have their own shortcomings., Purpose: The purpose of this pilot clinical study was to assess the suitability of an infrared sensor scan device in procuring the diagnostic data parameters for completely edentulous patients., Material and Methods: Twelve completely edentulous participants were enrolled in the study. For each, the distance between the arches was measured by 2 clinical techniques at 3 common reference points, M1, M2, M3, for the maxillary arch and m1, m2, m3 for the mandibular arch. The control group measurements were recorded by using a standard diagnostic mounting procedure on a semi-adjustable articulator, and the experimental group measurements were recorded by using an infrared sensor scan device. To convert the analog infrared sensor output into digital data, the Arduino ADC software program was used. The data from both study groups were statistically compared by using the independent t test (α=.05)., Results: No significant difference in variation was found between the mean measurements of the device and diagnostic mounting (P>.05). The maximum variation recorded by the experimental device was 1.7 mm, whereas the minimum variation was 0.8 mm (mean 1.25 mm)., Conclusions: The use of precisely calibrated infrared sensors may be a cost-effective option for diagnostic mounting., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Immediate complete denture insertion followed by removal of teeth provides a positive emotional response to the patient by saving the embarrassment of being edentulous and minimal alteration in general appearance, muscle tone, and speech. The patient gets adjusted to the change more quickly; the healing period is faster and less painful. However, the fabrication of immediate denture requires different impression techniques to follow than routine conventional complete denture procedure. This case report presents the fabrication of conventional immediate denture using Campagna impression technique which appears to be more precise among all the techniques as it ensures a similar degree of accuracy of the borders in the dentulous as well as edentulous region of the maxillary dental arch. To provide optimum benefit from the constructed denture, a lingualized balanced occlusal scheme was given. [ABSTRACT FROM AUTHOR]

Statement of Problem: The use of digital interocclusal registration scans for virtual articulation and mounting has been studied extensively; however, the accuracy of the cross-mounting procedures in a digital workflow is not well understood., Purpose: The purpose of this in vitro study was to compare the accuracy of digital and conventional cross-mounting by measuring the 3-dimensional deviation at each step of sequential cross-mounting., Material and Methods: A set of reference casts and complete arch interim restorations was prepared for complete arch complete-coverage restorations, hand-articulated, and mounted in an articulator. The reference casts were then scanned with and without the interim restorations to generate 4 reference casts for cross-mounting. For the conventional group, 15 sets of the 4 casts were printed. Polyvinyl siloxane interocclusal registration records were made of the reference casts for each set, and casts were sequentially cross-mounted. For the digital workflow, 15 sets of bilateral interocclusal registration scans were made of the mounted reference casts and used to align the cast scans. Three-dimensional deviations at 2 anterior and 2 posterior points were recorded between the experimental mountings and the reference casts on each set of casts. Nonpaired t test and analysis of variance (ANOVA) were used to compare the average discrepancy between the 2 groups, and the pooled anterior versus posterior discrepancies were compared (α=.05)., Results: A significant difference was found between conventional and digital cross-mounting procedures (P<.001), but no significant difference was found in either group, conventional (P=.116) or digital (P=.987), at each step of the sequential mountings. The mean ±standard deviation at the final set of related casts in the conventional workflow was 201.6 ±137.0 μm and that in the digital group was 50.3 ±47.5 μm, with a significant difference between anterior and posterior deviations in the digital group (P=.028), but not in the conventional group (P=.143). The mean ±standard deviation anterior conventional deviation was 175.6 ±119.2 μm and that in the digital group was 36.9 ±30.9 μm. The mean ±standard deviation posterior conventional deviation was 227.6 ±50.2 μm and that in the digital group was 63.7 ±57.2 μm., Conclusions: Digital cross-mounting was more accurate than conventional cross-mounting, although increased deviation was found in the anterior region compared with the posterior region., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Aim: The purpose of this study is to investigate the interchangeability of newly acquired, short-term used, and long-term used semi-adjustable articulators., Materials and Methods: Metal analogs of partially dentate maxillary and mandibular arches were mounted on twelve semi-adjustable Stratos 300 articulators, divided into three groups based on usage over time: New, short-term used (<2 years), long-term used (>2 years) articulators. Each articulator was calibrated according to manufacturer guidelines, ensuring consistency. Occlusal contact forces were recorded using a T-scan III device with a pressure-mapping sensor. Maximum intercuspation (MIP) contact magnitudes were recorded by two calibrated examiners at 10-second intervals, ensuring reliable data collection across all conditions., Results: In MIP, tooth #9 consistently exhibited the highest contact percentages across all articulator conditions, with percentages of 22.2% in the new articulator, 21.8% in the short-term used articulators, and 21.5% in long-term used articulators, indicating stable contact force distribution. Tooth #12 consistently showed the lowest MIP contact percentages, suggesting minimal occlusal force in this region due to its absence. Contact forces, measured at 10-second intervals, showed no significant differences among the different articulator conditions in MIP ( p > 0.01)., Conclusion: Within the limitations of this in vitro study, the calibrated Stratos 300 semi-adjustable articulator maintained superior accuracy over time., Clinical Significance: The study confirms that the calibrated Stratos 300 semi-adjustable articulators provide consistent and accurate occlusal measurements over time, regardless of their usage over time. How to cite this article: Almalki A, Kutkut N, Althubaitiy R, et al. Interchangeability of Contemporary Semi-adjustable Articulators Used Over Time: An In Vitro Study. J Contemp Dent Pract 2024;25(9):869-872.

Background: While we attempt to restore occlusion in completely edentulous patients there is a consensus among clinicians to articulate the cast using average value and avoid performing facebow transfer. Various studies question the application of facebow transfer in the fabrication of removable complete denture fabrication., Aim: This study was therefore aimed to study the effect on condylar guidance with casts mounted by the facebow method, Bonwill's method, and radiographic method., Methods: A cross-sectional study was performed using casts of edentulous patients attending the Department of Prosthodontics. After establishing a tentative jaw relationship using wax occlusal rims in the edentulous participants, the casts were mounted by Bonwill's method and the facebow transfer method to a semi-adjustable articulator. Protrusive records of the subjects were used to program the articulator to obtain the condylar guidance values. Digital lateral cephalographs were made both in centric and protrusive jaw relationships. The mandibular condyles were then traced and overlapped to obtain radiographic values. The condylar guidance values obtained by Bonwill's method, facebow method and radiographic method were compared using Wilcoxon's signed rank test and Mann-Whitney U test. The SPSS Statistics for Windows (Version 21.0. Armonk, NY, USA:IBM Corp.), and, at a probability value of 0.05, the significance of every statistical test was predetermined., Results: Ten edentulous 45-70 year olds participated in the study. The mean discrepancy between radiography and facebow methods was 12.8° for the right side and 12.7° for the left (P < 0.005). The difference between radiography and Bonwill's methods was significant (P < 0.005), with a mean difference of 34.3° for the right side and 34.7° for the left side. The difference between Bonwill's method and the facebow method was significant (P < 0.005), with a mean difference of 21.5° for the right side and 22° for the left side., Conclusion: The condylar guidance values obtained by clinical methods (Bonwill's and Facebow) were significantly lesser (P < 0.005) compared to the values obtained by radiographic method., (Copyright © 2024 Copyright: © 2024 Nigerian Journal of Clinical Practice.)

Objectives: To compare the trueness of maxillomandibular relationship between articulated 3D-printed and conventional diagnostic casts in maximum intercuspation (MIP)., Methods: Reference casts were articulated in MIP, and scanned using a Coordinate Measurement Machine (CMM, n = 1). Digital scans were made from the reference casts by using an intraoral scanner (IOS, n = 10) (Trios 4; 3Shape A/S). IOS scans were processed to create 3D-printed casts by using MAX UV385 (Asiga) and NextDent 5100 (3DSystems) 3D-printers. The conventional workflow implemented vinylpolysiloxane (VPS) impressions and Type IV stone. Stone and 3D-printed casts were articulated and digitized with a laboratory scanner (E4; 3Shape A/S). The 3D-printed casts were scanned on two occasions: with and without positioning pins. Inter-arch distances and 3D-contact area were measured and compared. Statistical tests used were Shapiro-Wilk, Levene's, Welch's t-test, and 2-way ANOVA (α=0.05)., Results: IOS group showed similar or better maxillomandibular relationship trueness than stone casts and 3D-printed casts (p < 0.05). 3D-contact area analysis showed similar deviations between 3D-printed and stone casts (p > 0.05). The choice of 3D-printer and presence of positioning pins on the casts significantly influenced maxillomandibular relationship trueness (p < 0.05)., Conclusions: Articulated 3D-printed and stone casts exhibited similar maxillomandibular relationship trueness., Clinical Significance: Although 3D-printing methods can introduce a considerable amount of deviations, the maxillomandibular relationship trueness of articulated 3D-printed and stone casts in MIP can be considered similar., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Statement of Problem: The accuracy of a maxillomandibular relationship acquired by intraoral scanners (IOSs) has been previously analyzed; however, the impact of the interocclusal space on the accuracy of the maxillomandibular relationship remains unknown., Purpose: The purpose of this in vitro investigation was to evaluate the influence of the interocclusal space (0, 1, 2, 3, or 4 degrees of incisal opening in the articulator) on the accuracy of the maxillomandibular relationship captured with an IOS., Material and Methods: Markers were attached to the first molars and canines of maxillary and mandibular diagnostic casts, which were mounted on a semi-adjustable articulator, and digital scans were acquired (TRIOS 4). Both digital scans were duplicated 100 times and distributed into 5 groups depending on the incisal pin opening in the articulator (n=20): 0 (Group 0), 1 (Group 1), 2 (Group 2), 3 (Group 3), and 4 degrees (Group 4). In Group 0 (control), the casts were maintained in maximum intercuspation (MIP) with the incisal pin of the articulator set at 0 degrees. Then, a bilateral virtual occlusal record was acquired and automatically processed by using the IOS software program. A laboratory scanner (Medit T500) was used to digitize the mounted casts. The same procedures were completed in Groups 1, 2, 3, and 4 but with the incisal pin set at 1, 2, 3, and 4 degrees respectively. The interlandmark distances were used to calculate the discrepancies between the control and groups tested. One-way analysis of variance (ANOVA) and pairwise comparison Tukey HSD tests were used to inspect the data (α=.05)., Results: The interocclusal space available when capturing the occlusal records affected the trueness of the maxillomandibular virtual relationship measured (P<.001). Group 0 (135 μm) obtained the highest distortion, while Group 3 (73 μm) and Group 4 (71 μm) showed the lowest distortion. Additionally, the interocclusal space available (P<.001) impacted the precision of the maxillomandibular virtual relationship measured. Group 0 (111 μm) obtained the highest distortion, while Group 4 (precision mean value of 59 μm) had the lowest distortion among the groups tested., Conclusions: The interocclusal space available when acquiring virtual bilateral occlusal records using the IOS tested impacted the accuracy of the maxillomandibular relationship. The smallest available interocclusal space tested (maximum intercuspation) showed the worst trueness and precision mean values, while the group with the largest interocclusal space available had the highest trueness and precision mean values among the groups studied., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

The surgical correction of dento-maxillofacial deformities for aesthetic reasons is increasingly required. In order to obtain the results that our patients expect, it is necessary to very thoroughly evaluate every aesthetic detail of the face, because an optimal result comes from the correction of all parameters. The region of the mandibular angles is very important in determining the final aesthetics but is at the same time difficult to predict. Traditional programming based on model surgery is inadequate in this regard compared to that based on CT (Computed Tomography) reconstruction. The authors explain the reasons for this and demonstrate the problems by reporting a typical clinical case.

Purpose: Published literature on mandibular movements is extensive, but it lacks scientific robustness and is understandably controversial. This preliminary study recorded and assessed characteristic forms and condylar path inclination patterns during mandibular protrusion and opening in completely edentulous subjects. These features facilitate the setting of condylar guidance records on articulators.Materials and Methods: A convenience study sample of 60 asymptomatic edentulous patients (aged 58 to 74 years) was provided with new complete dentures. After localizing hinge axis movement, sagittal condylar paths were recorded and analyzed with an electronic axiograph (AXIOCOMP, SAM).Results: Protrusion and opening movement patterns showed completely different characteristics. During protrusive movement, condylar paths showed a sinusoidal pattern (51%), and condylar inclination was low at 1 mm (32.2 degrees) and 2 mm (40.4 degrees). Conversely, during the opening movement, the most frequent pattern found was the classical convex form (57%). Inclinations were higher: 50.8 degrees at 1 mm and 50.7 degrees at 2 mm.Conclusions: Completely edentulous subjects present radically different sagittal condylar paths when compared with dentate patients. These differences result from alterations in disc-condyle relationships and morphologic changes in bone structure. No link was observed between condylar paths recorded in protrusion and opening movements. Consequently, condylar guidance for articulators should be set using recordings from protrusive movements. [ABSTRACT FROM AUTHOR]

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 tocompare 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. [ABSTRACT FROM AUTHOR]

The article describes the options for transferring the upper jaw model to the articulator in the correct position, based on the patient's natural head position (NHP) and taking into account the natural asymmetries. It mentions that interplay of digital technologies with analogue procedures reduces the number of try-ins in the patient's mouth, and the result is an efficient procedure that offers high accuracy and reproducibility at the same time.

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Statement of Problem: Occlusal collisions of articulated intraoral digital scans can be corrected by intraoral scanners (IOSs) or dental design software programs. However, the influence of these corrections on the accuracy of maxillomandibular relationship is unclear., Purpose: The purpose of this clinical investigation was to measure the effect of occlusal collision corrections completed by the IOSs or dental design software programs on the trueness and precision of maxillomandibular relationship., Material and Methods: Casts of a participant mounted on an articulator were digitized (T710). The experimental scans were obtained by using 2 IOSs: TRIOS 4 and i700. The intraoral digital scans of the maxillary and mandibular arches were obtained and duplicated 15 times. For each duplicated pair of scans, a bilateral virtual occlusal record was acquired. Articulated specimens were duplicated and assigned into 2 groups: IOS-not corrected and IOS corrected (n=15). In the IOS-not corrected groups, the IOS software program postprocessed the scans maintaining the occlusal collisions, while in the IOS-corrected groups, the IOS software program eliminated the occlusal collisions. All articulated specimens were imported into a computer-aided design (CAD) program (DentalCAD). Three subgroups were developed based on the CAD correction: CAD-no change, trimming, or opening the vertical dimension. Thirty-six interlandmark distances were measured on the reference and each experimental scan to compute discrepancies by using a software program (Geomagic Wrap). Root mean square (RMS) was selected to compute the cast modifications performed in the trimming subgroups. Trueness was examined using 2-way ANOVA and pairwise comparison Tukey tests (α=.05). Precision was evaluated with the Levene test (α=.05)., Results: The IOS (P<.001), the program (P<.001), and their interaction (P<.001) impacted the trueness of the maxillomandibular relationship. The i700 obtained higher trueness than the TRIOS 4 (P<.001). The IOS-not corrected-CAD-no-changes and IOS-not-corrected-trimming subgroups obtained the lowest trueness (P<.001), while the IOS-corrected-CAD-no-changes, IOS-corrected-trimming, and IOS-corrected-opening subgroups showed the highest trueness (P<.001). No significant differences in precision were found (P<.001). Furthermore, significant RMS differences were found (P<.001), with a significant interaction between Group×Subgroup (P<.001). The IOS-not corrected-trimmed subgroups obtained a significantly higher RMS error discrepancy than IOS-corrected-trimmed subgroups (P<.001). The Levene test showed a significant discrepancy in the RMS precision among IOSs across subgroups (P<.001)., Conclusions: The trueness of the maxillomandibular relationship was influenced by the scanner and program used to correct occlusal collisions. Better trueness was obtained when the occlusal collisions were adjusted by the IOS program compared with the CAD program. Precision was not significantly influenced by the occlusal collision correction method. CAD corrections did not improve the results of the IOS software. Additionally, the trimming option caused volumetric changes on the occlusal surfaces of intraoral scans., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Aim: There is an ongoing debate about the benefits of the facebow and individual articulator settings in prosthodontics when compared with simpler methods. The present study aims to determine whether the implementation of novel algorithmic articulator concepts may be an alternative to avoid dynamic interference contacts during the design process of fixed posterior restorations, and to what extent the occlusal morphology of the restoration is affected., Materials and Methods: From a chairside CAD database, a total of 50 clinical patient cases documenting 61 planned fixed restorations in the posterior tooth region were selected. A common CAD software program was used for the automated knowledge-based design process. When designing the restorations, functional concepts were applied, including the pure static occlusion, the average articulation, three different articulator settings as a control, and a combination of a broad range of articulation parameters (the full range dynamic articulation). The resulting dynamic contact points were compared both visually and metrically with a monitoring software program., Results: There is a highly significant difference in avoiding dynamic interference contacts when applying the full range dynamic articulation compared with the pure static occlusion (P < 0.001) and the average articulation (P < 0.001). Furthermore, the superimposition revealed that the surface of the restorations showed nearly no visual morphologic changes after virtually grinding-in the interpenetrating contact points., Conclusion: The full range dynamic articulation can be used for the design of small fixed posterior restorations to avoid most dynamic interference contacts without the need for determining individual parameters for each patient.

Various techniques have been developed for a 3-dimensional (3D) virtual patient. However, those techniques do not enable the registration of the alignment of the facial and intraoral digital scans, the registration for the mounting on the virtual articulator, and the integration of the natural head position (NHP) together. In the present manuscript, a scan body system is described that assists with the translation of the horizon orientation within the NHP of the patient into a computer-aided design software program. Additionally, the scan body system facilitates the facial and intraoral alignment, as well as the mounting of the maxillary virtual cast on the virtual articulator. This scan body system facilitates the integration of the 3D virtual patient and reduces chair and laboratory time., (Copyright © 2022 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objective: The purpose of this article was to introduce a method for the digital application of three-dimensional (3D) diagnosis and treatment with a virtual articulator and 3D data., Clinical Consideration: With the use of cone-beam computed tomography (CBCT) and intraoral and facial scans, we can create a virtual articulator and evaluate the mandibular position in maximum intercuspation and centric-related occlusion for the patient with an unstable occlusion and temporomandibular disorders (TMD). Based on this, we treated a case using a digital mandibular position indicator (MPI) and fabricated a stabilization splint using a 3D printer. This approach eliminates the traditional impression or model mounting process and the analog face bow transfer. Furthermore, the design of the stabilization splint is accomplished using software., Conclusions: The approach outlined in this article offers the potential for a digital diagnosis and treatment process by seamlessly integrating CBCT, intraoral scans, and facial scans with a high degree of accuracy. This may enhance precision in diagnosis and treatment planning, especially for patients with complicated TMD, in addition to facilitating effective communication with orthodontic patients who require thorough attention., Clinical Significance: Utilizing a virtual articulator and digital MPI for the occlusal evaluation of patients with TMD and unstable occlusion makes it possible to diagnose and analyze the occlusal condition accurately. This approach also allows for precision and efficiency in treatment., (© 2023 The Authors. Journal of Esthetic and Restorative Dentistry published by Wiley Periodicals LLC.)

Aim: The aim of the study was to compare two radiographic techniques, orthopantomograph (OPG), and cone-beam computed tomography (CBCT) in determining the sagittal condylar guidance (SCG) and to find out if CBCT can serve as an alternative aid to program semi-adjustable and fully adjustable articulators. Materials and Methods: Following the inclusion and exclusion criteria, 40 individuals (20 males and 20 females) aged between 20 and 40 years were selected. An OPG and a CBCT radiograph were obtained for each individual. Using appropriate software, the SCG was measured for both the sides, for both the radiographic methods. The values for each individual were obtained by two investigators for both the methods using the respective software and the average value was taken. After performing the Shapiro–Wilk test, paired t-test was used to compare the mean difference pairwise (for both right and left side) while t-test was used to compare the mean difference between two groups. Results: Results showed that the right and left SCG values obtained from both, OPG and CBCT methods were comparable and there were no significant differences. Statistically significant difference was not found between the left and ride side condylar inclination values for both the sex obtained from both the methods. With increasing age, condylar inclination values obtained from both the radiographic methods tend to decrease. The values for SCG obtained from both the methods (CBCT and OPG) are thus comparable and correlated. Conclusion: The values for SCG obtained from both the methods (CBCT and OPG) are comparable and correlated. Thus, CBCT being a better radiographic technique can be used for obtaining the condylar inclination for programming the semi-adjustable and fully adjustable dental articulators.

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

The article focuses on five most forgotten options in the virtual articulator. It mentions CAD software and created construction and the digital world around it around antagonist, gingival scan and neighboring teeth and practitioner with articulation paper and articulation foil. It also mentions how the practitioner controls the occlusion of construction at this point in mouth would perceive and should be digital existing contact relationships.

Articulators are mechanical devices representing temporomandibular joints and jaw members which simulates jaw movements. Maintaining occlusion is of great importance as mouth plays an important role in protecting the whole internal body. In this way, the mouth could be referred to as the best articulator. A well structured, self evaluable set of questions were prepared and uploaded in a survey planet link. The data collected by surveying among 100 active participants of undergraduate students, it was analysed and computed in SPSS software. The advantages, disadvantages, cost effectiveness of the semi adjustable articulators are questioned and the responses discussed. The level of awareness has been known which the knowledge oriented questions are their responses. There exist a signal level of knowledge and positive attitude towards semi adjustable articulators. There exists a positive attitude and significant knowledge and awareness regarding semi adjustable articulators among the undergraduate students. Further studies and awareness may bring out its accuracy in improvising the various fields of dentistry. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the study is to analyse the knowledge, awareness and practices of facebow and its significance in full mouth rehabilitation procedures among general practitioners. A questionnaire based survey is conducted among the general practitioners. The questionnaire contained questions such as the type of facebow used, the type of articulator preferred and the patient satisfaction. The data is collected and tabulated in excel sheets. The data analysis is done using SPSS software and the output is represented. 21.5% of the participants used facebow for full mouth rehabilitation procedures while 62.6% of them did not use the facebow. The most commonly preferred type of facebow included the arbitrary facebow compared to kinematic face bow. 52.3% of the participants are aware of the importance of facebow which helps in reducing the occlusal errors whereas 14.00% of them are not aware of the same. Within the limitation of the study, it can be concluded that the knowledge, awareness and practices among the general practitioners based on facebow and its significance in full mouth rehabilitation procedures are found to be inadequate. More knowledge and practices of using facebow in full mouth rehabilitation should be incorporated as a regular practice for dental practitioners to reduce occlusal complications. [ABSTRACT FROM AUTHOR]

Purpose: During extensive prosthodontic treatment, the use of an accurately adjusted articulator is recommended to simulate mandibular movements. This clinical study was undertaken to assess any possible effect of the underlying skeletal pattern on programming articulator settings. Materials and Methods: Subjects (n = 73, mean age: 22.8 ± 6.8 years) were recruited from a dental school and two regional specialist orthodontic units. Subjects were allocated into groups based on their underlying sagittal (I, II, or III) and vertical (reduced, average, or increased) skeletal patterns by three orthodontists and three prosthodontists who examined their profile photographs. Electronic pantographic recordings were made of each subject using the Cadiax Compact system to record the sagittal condylar inclination (SCI), progressive mandibular lateral translation (PMLT), and immediate mandibular lateral translation (IMLT). Results: Agreement between assessors for sagittal skeletal pattern classification was excellent (97% for total or good agreement); agreement for vertical skeletal pattern was high, but at a lower level than that for sagittal relationships (70% for total or good agreement). SCI settings for sagittal II subjects were significantly higher than those for sagittal I (P < .05) and sagittal III (P < .001) subjects. Differences were statistically significant, with mean SCI differences of 4 and 7 degrees, respectively. No statistical difference could be observed between SCI values in the sagittal I and III groups. Subjects with an average vertical skeletal pattern had SCI values lower than those with a reduced vertical skeletal pattern (P = .058) and an increased vertical skeletal pattern (P < .01, statistically significant). No patterns could be determined for PMLT or IMLT between the study groups. Conclusion: During prosthodontic treatment of patients with a noticeable skeletal discrepancy, appropriate consideration should be given to customizing SCI values. [ABSTRACT FROM AUTHOR]

When patients of differing ethnicities are treated with one bracket system, negative consequences for the occlusion can result. This study investigated the crown angulation and inclination on study casts of 60 Northern Thais (30 males and 30 females) with a good occlusion. In all study casts, each tooth (except the third molars) was evaluated with the orthodontic Torque Angulation Device (TAD) twice on the right side; this was also performed twice on the left side. The mean of the two evaluations was used for the statistical analysis. The means of the males and females were compared with the independent Student t test. The results were that the crown angulation of the mandibular first and second molars was significantly higher in females (P <.01) and that the crown inclination of all teeth did not differ between the two sexes. [ABSTRACT FROM AUTHOR]

The thickness of a mouthguard at the occlusal surface strongly influences not only safety levels, but also stomatognathic function and sports performance. However, to date, there is no method for securing occlusal consistency. In the present study, a "Trial Occlusal Spacer" was prepared to secure occlusal consistency in custommade mouthguards. It was made from plastic spherules (2 and 3 mm in diameter) placed inside a thin plastic bag. This "Occlusal Spacer" is used in the bite registration step on an articulator. The occlusal thickness obtained with and without the Occlusal Spacer was compared in order to determine the effectiveness of the Occlusal Spacer. The Occlusal Spacer is quite easy to use and is effective in obtaining occlusal consistency. It serves as a valuable new tool for the production of mouthguards with thicknesses tailored to individual needs. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the hamulus-incisive-papilla (HIP) plane as an alternative for transferring the three-dimensional position of a patient's maxilla to an articulator.Materials and Methods: Camper, Frankfurt horizontal, occlusal, and HIP planes were evaluated in 21 patients' computed tomography scans and compared to one another.Results: Analysis of variance showed significant differences between all planes, with the HIP plane being closest to the occlusal plane (HIP-OP: 0.6 ± 4.0 degrees). Frankfurt and Camper planes, being more peripheral, showed higher geometric asymmetries.Conclusion: The HIP plane, when used for articulator mounting, results in a closer and more technically reliable patient relationship in a clinical and laboratory context. [ABSTRACT FROM AUTHOR]

This is a treatment report of a patient with an anterior open bite and predominance of vertical growth. Multiloop edgewise archwire (MEAW) mechanics were used and resulted in an efficient bite closure and good occlusion. For retention, a bonded 3-3 retainer was used in the mandible whereas a wraparound retainer was employed in the maxilla. [ABSTRACT FROM AUTHOR]

The Class III malocclusion with mandibular prognathism and open bite can be a result of excessive mandibular growth, underdevelopment of the maxilla, environmental factors, and trauma to the jaws. Correction of this malocclusion can involve an orthodontic or a combined orthodontic-orthognathic approach. Skeletal asymmetries can complicate this situation, making treatment more difficult. This skeletal Class III deformity with skeletal open bite case presentation involves treatment with a combined orthodontic-bimaxillary orthognathic approach following rhinoplasty. In addition, the patient's postoperative skeletal and dental stability was well-maintained after 1 year postoperation. [ABSTRACT FROM AUTHOR]

The purpose of this case report is to demonstrate the relation between occlusal overload and peri-implant bone loss and the reversal of the situation after removal of the offending forces. The placement of an unstable removable prosthesis on 3 well-integrated implants that had been stable for 9 years caused noticeable bone loss after 6 months. The elimination of the traumatic occlusion reversed the situation, and a remarkable healing of the peri-implant tissue occurred until the pretrauma condition was nearly restored. The condition has been stable for the past 4 years. [ABSTRACT FROM AUTHOR]

Aim: This article describes the treatment of a patient with a Class II malocclusion and bilaterally impacted canines using a Jasper jumper appliance. An unfavorable side effect of the appliance became a benefit as part of the treatment. Methods: Treatment objectives were to erupt the impacted canines, expand the decreased intermolar width, and obtain a well-balanced profile, with a Class I occlusion. The widening effect of this appliance on the maxillary molars was expected to help increase the intermolar distance. Results: Favorable changes were noted, both in the occlusion and in the profile. Class I canine and molar relationships with ideal overjet and overbite were achieved. Overbite and overjet were decreased by a combination of retrusion and extrusion of the maxillary incisors, and protrusion and intrusion of the mandibular incisors. The maxillary canines were erupted successfully, with healthy gingival tissue. The crossbite in the right posterior segment was corrected as a result of the increase in the intermolar distance. Conclusion: The results gained were primarily dentoalveolar, rather than skeletal. There has been an improvement in the occlusion and esthetics. [ABSTRACT FROM AUTHOR]

When the patient who has excessive anterior facial height desires treatment for the correction of a malocclusion, the dimension of the dentition should be respected. The clinician must adhere to the anterior, posterior, vertical, and lateral limits of each patient's dentition--providing the musculature is normal--when the treatment plan is formulated. The goals of esthetics, health and function, stability, and treatment in harmony with growth are as valid for the high-angle patient as they are for a patient with a more normal vertical dimension. The diagnostic decisions made for the high-angle patient should be predicated on nonexpansion of the mandibular arch. Mandibular incisors must be overly upright. In addition, a decision on the mandibular third molars must be made prior to anchorage preparation--because their relationship to the mandibular second molars is critical if anchorage is to be properly prepared. A discussion of these topics as well as an illustrative case report are presented in this article. [ABSTRACT FROM AUTHOR]

This study examined the effects of the vertically activated bite block, a new appliance designed for maxillary molar intrusion in open bite malocclusion, on the dentofacial structures in 1 adolescent patient and 1 adult patient. The vertically activated bite block consists of 2 parts, the main block and an auxillary segment. The auxilliary segment is separated bilaterally from the main block in the posterior region and connected bilaterally to the main block in the palatal region by open jackscrews. Closing the jackscrews moves the auxiliary segment toward the palate, thereby inducing molar intrusion. The present study achieved a reduction in open bite, using the VABB through: (1) active intrusion of the maxillary molars; (2) control of posterior vertical alveolar development and/or compensatory eruption of the mandibular molars; (3) stimulation of anterior vertical alveolar development by restriction of the tongue; and (4) anterior repositioning of mandible. Achieving these dentoalveolar and skeletal changes are required treatment objectives in cases of skeletal open bite. As a result of attaining these objectives, the open bite was eliminated in 1 early growth and 1 late growth patient by 14 mm and 6 mm, respectively. [ABSTRACT FROM AUTHOR]

Clinical effects of forces applied by dental occlusion on the periodontium have been evaluated for decades. Historically, trauma from occlusion has been considered as a major etiologic factor of inflammatory periodontal diseases, while some researchers have interpreted it to be of less importance or without any detectable importance in periodontics. In this study, five three-dimensional models of a maxillary central incisor were created using ANSYS 5.40. The only difference in each model was the height of the alveolar bone that showed from normal height (13 mm of alveolar bone height) to 8 mm of alveolar bone loss (5 mm of alveolar bone height). Five-point forces of 0.3 N summing up to 1.5 N were applied in a parallel line, 1 mm apical to the incisal edge on the palatal side in a palatolabial direction. The maximum (S1) and minimum (S3) principal stresses in the nodes of the labial side of the periodontal ligament (apical to the alveolar crest) were assessed. Analysis was done using the finite element method. An increase of S1 (up to 16 times in the cervical and 11.25 times in the apical area) and S3 (up to 17.13 times in the cervical and 9.9 times in the apical area) in comparison lo the normal model was shown. The highest stress levels were traced in the subcervical area, except for the last model (8 mm of the alveolar bone loss). According to the results of this study, 2.5 mm of alveolar bone loss can be considered as a limit beyond which stress alterations were accelerated. Based on the FEM analysis, alveolar bone loss increases stress (S1 and S3) produced in the PDL, in spite of applying the same force vector. (Quintessence int 2004:35:835-843) [ABSTRACT FROM AUTHOR]

The aim of this systematic review of population-based studies was to establish whether or not associations exist between different types of malocclusions, as well as factors of functional occlusion (eg, occlusal interferences, nonworking-side occlusal contacts) and temporomandibular disorders (TMD) in adults 20 years or older. Defined criteria were employed in the search of MEDLINE and EMBASE databases, as well as in a manual search. Finally, using inclusion criteria (eg, random sampling from residents' registration office files or census lists, adequate response rates), out of 22 preselected studies, four relevant population-based studies on this subject were found. Eighteen studies were excluded because of insufficient description of material and methods (eg, lack or unclear description of sample method, randomization, age distribution), mixed under- and over-20-year-old study population, or different outcome of interest (eg, tooth loss, dentures) The methodologic quality of the selected studies was established with a quality assessment list. The average total methodologic score achieved was 43 out of a possible 100 points. Few associations were reported between malocclusion and parameters of functional occlusion and clinical as well as subjective TMD, and these associations were not uniform. No particular morphologic or functional occlusal factor became apparent. Additionally, the occlusal factors found were partly protective for TMD, ie, subjects with these occlusal parameters snowed fewer signs and symptoms of TMD [angle Class II malocclusion, deep bite, anterior crossbite). A positive relationship was only described in two cases—between the number of rotated lateral teeth and subjective symptoms of dysfunction, and between excessive abrasions and clinical dysfunction. In neither case, however, was the strength of the correlation given in summary, few associations were established between malocclusion or functional occlusion and signs and symptoms of TMD. In view of the small number of randomized studies and their methodologic quality, these results should be verified through further valid representative studies. [ABSTRACT FROM AUTHOR]