Search

Background/Objectives: The relation between the orthopedic temporomandibular joint (TMJ) instability and temporomandibular disorder (TMD) most commonly remain unrecognized by orthodontists. In this study we aimed to evaluate the dentofacial characteristics and temporomandibular disorder symptomatology of patients with orthopedic instability before and after deprogramming with a stabilization splint. Methods: Sixty patients with the signs and symptoms of TMD were assessed using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and underwent stabilization splint therapy to place the condyles in a more stable musculoskeletal position. The extent of condylar displacement was evaluated using the condylar position indicator (CPI). Sixteen angular and linear hard tissue landmarks were traced and compared from lateral cephalograms taken in the maximum intercuspation (MI) position before, and in the centric relation (CR) position after, the splint therapy. Results: Following the splint therapy, the signs and symptoms of TMD were significantly reduced or completely eliminated in more than 90% of patients. Compared with the values registered before the splint therapy, a significant reduction in the mean values of condylar displacement was observed on both sides of the vertical (p < 0.001), horizontal (p < 0.05), and transverse (p < 0.001) planes of space after the splint therapy. A comparison of pre- and post-splint lateral cephalograms revealed that, following the splint therapy, the mandible moved more posteriorly and rotated in a more clockwise direction. Conclusions: In patients with orthopedic instability and the signs and symptoms of TMD, muscle deprogramming with a stabilization splint therapy is highly recommended to improve the health of the temporomandibular joint and masticatory structures and contribute to a more correct orthodontic diagnosis. [ABSTRACT FROM AUTHOR]

Copyright of West China Journal of Stomatology is the property of Sichuan University, West China College of Stomatology 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.)

This study compares the anterior jig method with the classic bimanual technique for recording intermaxillary relations in patients who have lost anterior occlusal stops. A total of 51 patients (36 females, 16 males, mean age 42.6 years) had their anterior teeth prepared from canine to canine, resulting in the loss of anterior occlusal stops. Occlusal and incisal records were obtained using 3Shape (Denmark) digital scanning technology and analyzed with Exocad (Exocad GmbH, Germany) software. The results showed that the anterior jig method significantly reduced discrepancies, with an average difference of 0.837 mm, compared to the classic method. This difference was statistically significant (Mann-Whitney, p

This study compares the anterior jig method with the classic bimanual technique for recording intermaxillary relations in patients who have lost anterior occlusal stops. A total of 51 patients (36 females, 16 males, mean age 42.6 years) had their anterior teeth prepared from canine to canine, resulting in the loss of anterior occlusal stops. Occlusal and incisal records were obtained using 3Shape (Denmark) digital scanning technology and analyzed with Exocad (Exocad GmbH, Germany) software. The results showed that the anterior jig method significantly reduced discrepancies, with an average difference of 0.837 mm, compared to the classic method. This difference was statistically significant (Mann-Whitney, p<0.001), especially among female patients. The anterior jig method provided better condylar positioning and minimized errors associated with the classic technique. These findings highlight the superior accuracy of the anterior jig method for recording intermaxillary relations when anterior stops are lost, emphasizing its reliability over the classic method. [ABSTRACT FROM AUTHOR]

In patients with unstable mandibular movements who are accompanied by involuntary facial muscle movements and asymmetrical changes in the facial features, many difficulties exist in determining the vertical dimension of occlusion, recording centric relation, and transferring information about the occlusal plane. In this case, for a patient with unilateral facial nerve palsy who was edentulous for a long period of time, a CAD-CAM provisional prosthesis was fabricated using a 3D printing customized gothic arch tracer and a prefabricated occlusal plane recorder, the POP bow system, to achieve a stable interarch relationship. Afterwards, a full mouth implant fixed prosthesis was fabricated by delivering an appropriate vertical dimension of occlusion, a reproducible centric relation, and a correct three-dimensional occlusal plane, and continuous maintenance was performed to restore functional and aesthetic oral health to the patient. [ABSTRACT FROM AUTHOR]

Background and aim. This study aims to explore the most widely used methods for managing patients who are completely edentulous to determine the intermaxillary relations, also known as the centric relation and vertical dimension of occlusion. Material and methods. The information sources have been identified through searches of medical databases. A 20-year search frame, from 2001 to 2021 was performed. The terms “occlusal vertical dimension”, “totally edentulous”, “complete denture”, and “centric relation” were searched. The selected articles were acquired in full text, and two different authors resolved differences through conversation before evaluating them for inclusion. Results. Following the application of the search strategy, 514 articles were identified. 172 papers were screened after duplicate records were removed. Selecting the studies to be considered for inclusion in the first stage required considering their titles, abstracts, and studies’ significance to the study purpose. After obtaining the complete texts of the remaining twenty-seven papers, their relevance was evaluated. Conclusion. The relationship between the maxillary and mandibular arches is still established by the centric relation in occlusal examination and prosthetic treatment. Many methods with low variability and high intra-technical repeatability are available for recording centric relation. There is no one standard technique for recording the vertical dimension of occlusion; instead, the clinician must choose the most comfortable approach.

Abstract Background Finding and registering the maxillary–mandibular jaw relation is crucial in dental practice. Several comparative studies have been conducted to investigate the reproducibility and accuracy of techniques for determining the centric relation (CR) position of the mandible. The aim of our study was to determine which of seven different CR determination methods had the smallest deviation from the theoretical zero with the help of a digital mandibular motion analyser. The chosen theoretical zero position, the maximal intercuspal position (MIP), is the most reproducible and widely used position. Methods Thirty-four volunteers (24 females and 10 males) with a mean (SD) age of 29.1 (± 7.3) years with a negative history of temporomandibular disorder (TMD) participated in the study. A digital mandibular motion analyser was used to register the condylar position after the use of each technique for the determination of CR. The calibration was performed to the maximal intercuspal position (MIP) for each volunteer. The investigated techniques were (A) the gothic arch tracer, (B) the adduction field method, (C) Dawson’s bimanual manipulation, (D) the patient placing the tongue tip on the palatal rugae, (E) the patient placing the tongue tip to the border of the hard and soft palate, (F) the patient actively pulling the chin backwards, and (G) the examiner pushing the patient’s chin back. Results The position of the mandibular condyle was illustrated in a three-dimensional coordinate system, where the origin represented the MIP. Among the seven methods examined, five showed significant deviations compared to the MIP. Among these, two methods resulted in posterior deviation of the condyles. Methods C and E coincided with the MIP in all directions. Conclusions Within the limitations of our study, we found that the smallest deviations from our theoretical zero (MIP) among the investigated centric relation determining methods were obtained with the bimanual mandibular manipulation technique derived from Dawson and the placement of the tongue tip on the border of the hard and soft palate (linguomandibular homotrophy theory).

The gradual teeth wear with age is a natural phenomenon, but excessive wear beyond physiological levels can lead to vertical dimension loss, occlusal imbalance, temporomandibular joint disorders, and periodontal disease. In such cases, prosthodontic restoration becomes necessary emphasizing the importance of appropriate vertical dimension increase and stable occlusion in central relation (CR). In this case, a 74-year-old patient with clenching and grinding habit had severe teeth wear and after assessing interocclusal distance, wear degree, pronunciation, and facial profile, it was decided to perform full-mouth fixed prosthesis restoration with a 4 mm vertical dimension increase. And the significantly displaced Maximum Intercuspal Position (MICP) caused by parafunctional movements was re-established as a stable mutually protective occlusal relationship at centric relation and after a successful 4 months adaptation to provisional restorations, the final prosthesis was fabricated. During 4months of observation periods, stable occlusion in central relation and mutual protection occlusal relationships were maintained and the patient was satisfied with function and aesthetics, leading to this report. [ABSTRACT FROM AUTHOR]

Introduction: The multitude of definitions for the centric relation (CR) has sparked extensive scientific debates, marking significant milestones in the evolution of concepts in these fields. The discourse surrounding CR has remained contentious for over a century, and there is still a persistent divergence of perspectives. Aim: This narrative review aims to unravel the evolutionary trajectory of CR definitions, seeking to untangle the existing confusion prevalent within specialized literature. Moreover, it endeavors to provide guiding principles within this contentious domain, offering valuable insights to practitioners, students, educators, and researchers. Discussion: Dentistry has not arrived at a consensus definition and concept of CR. Even in the era of evidence-based dentistry, CR still leaves room for controversy. Conclusion: The evolution of the CR concept and its definition, progressing from the exact specification of the maxillomandibular relationship, temporomandibular joint elements, and hinge axis and to its partial “abandonment” due to the individuality and particularities of the patients, should be contextualized within the functional and adaptable nature of the stomatognathic system.

Background/Objectives: The relation between the orthopedic temporomandibular joint (TMJ) instability and temporomandibular disorder (TMD) most commonly remain unrecognized by orthodontists. In this study we aimed to evaluate the dentofacial characteristics and temporomandibular disorder symptomatology of patients with orthopedic instability before and after deprogramming with a stabilization splint. Methods: Sixty patients with the signs and symptoms of TMD were assessed using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and underwent stabilization splint therapy to place the condyles in a more stable musculoskeletal position. The extent of condylar displacement was evaluated using the condylar position indicator (CPI). Sixteen angular and linear hard tissue landmarks were traced and compared from lateral cephalograms taken in the maximum intercuspation (MI) position before, and in the centric relation (CR) position after, the splint therapy. Results: Following the splint therapy, the signs and symptoms of TMD were significantly reduced or completely eliminated in more than 90% of patients. Compared with the values registered before the splint therapy, a significant reduction in the mean values of condylar displacement was observed on both sides of the vertical (p < 0.001), horizontal (p < 0.05), and transverse (p < 0.001) planes of space after the splint therapy. A comparison of pre- and post-splint lateral cephalograms revealed that, following the splint therapy, the mandible moved more posteriorly and rotated in a more clockwise direction. Conclusions: In patients with orthopedic instability and the signs and symptoms of TMD, muscle deprogramming with a stabilization splint therapy is highly recommended to improve the health of the temporomandibular joint and masticatory structures and contribute to a more correct orthodontic diagnosis.

Background and aim. This study aims to explore the most widely used methods for managing patients who are completely edentulous to determine the intermaxillary relations, also known as the centric relation and vertical dimension of occlusion. Material and methods. The information sources have been identified through searches of medical databases. A 20- year search frame, from 2001 to 2021 was performed. The terms "occlusal vertical dimension", "totally edentulous", "complete denture", and "centric relation" were searched. The selected articles were acquired in full text, and two different authors resolved differences through conversation before evaluating them for inclusion. Results. Following the application of the search strategy, 514 articles were identified. 172 papers were screened after duplicate records were removed. Selecting the studies to be considered for inclusion in the first stage required considering their titles, abstracts, and studies' significance to the study purpose. After obtaining the complete texts of the remaining twenty-seven papers, their relevance was evaluated. Conclusion. The relationship between the maxillary and mandibular arches is still established by the centric relation in occlusal examination and prosthetic treatment. Many methods with low variability and high intra-technical repeatability are available for recording centric relation. There is no one standard technique for recording the vertical dimension of occlusion; instead, the clinician must choose the most comfortable approach. [ABSTRACT FROM AUTHOR]

According to some estimates, there are 60 000 hearing impaired people in Hungary. Their dental care can be difficult depending on the extent and type of hearing loss. It is the dentist’s job to ensure that communication is not impaired by speaking directly and clearly, ensuring that the mouth can be read and sometimes signalling through an interpreter or written communication. The patient has the right to obtain informed consent to dental treatment. We try to give an insight into the difficulties of care by presenting the complete oral rehabilitation of a hearing-impaired patient.

Background: Few terms and concepts have been so extensively debated in dentistry as the words 'centric relation' (CR). Debates involve its biological, diagnostic and therapeutic usefulness. Methods: A review of the literature on the current concepts on CR as a diagnostic or therapeutic aid in dentistry was provided. Clinical trials assessing the superiority of one CR recording method over the others to identify patients with temporomandibular disorders (diagnostic use) or to manage patients with prosthodontic or orthodontic needs (therapeutic use) were tentatively included. Results: Due to the absence of literature addressing either of the above targets, a comprehensive overview was provided. The diagnostic use of CR as a reference position to identify the correct position of the temporomandibular joint condyle within the glenoid fossa is not supported and lacks anatomical support. From a therapeutic standpoint, the use of CR can be pragmatically useful in prosthodontics as a maxillo‐mandibular reference position when occlusal re‐organization is warranted and/or when the position of maximum intercuspation is no longer available. Conclusions: The derived occlusal goals from a diagnostic misuse of CR are generally the result of circular reasoning, that is a technique is based on the recording of a certain condylar position that is believed to be 'ideal' and the treatment is considered successful when such position is shown by the specific instrument that was manufactured for that purpose. The term 'Centric Relation' might be replaced with the term 'Maxillo‐Mandibular Utility Position'. [ABSTRACT FROM AUTHOR]

Objective: This technique aimed to describe a fully digital workflow to register maxillomandibular relation for fixed prosthetic rehabilitation. Clinical Considerations: Mandibular kinematics could be reproduced in a four‐dimensional (4D) virtual patient based on the intraoral scan, facial scan, cone beam computed tomography, and jaw motion trajectory, which helped record centric relation and determine a proper occlusal vertical dimension in a virtual environment. The therapeutic position could be exported directly to the dental computer‐aided design software for digital waxing design with a facial scan. The 4D virtual patient was also used to verify the functional and esthetic outcomes of provisional restorations. Conclusions: This novel approach digitized the process of determination, delivery, and double‐check of maxillomandibular relation, thus contributing to the establishment of a completely digital workflow for fixed prosthetic rehabilitation. Clinical Significance: Registration of maxillomandibular relation, including centric relation and occlusal vertical dimension is critical to the success of prosthetic rehabilitation. Traditional procedures are complex and time‐consuming, and heavily rely on the clinical experience of dentists. A fully digital approach to creating a 4D virtual patient and registering the maxillomandibular relation is established, which guides to determine a proper occlusal vertical dimension in centric relation. Digital delivery and double‐check can simplify the conventional procedure and ensure that the determined maxillomandibular relation is reliable. [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.)

Support, retention, and stability of dentures are key factors in the use of complete dentures in edentulous patients. With the development of digital dentistry, attempts are being made to replace traditional treatment methods. Also, struggle to reduce the number of patient visits and to manufacture high-quality digitally fabricated dentures are ongoing. In this case, a digital denture was restored using a tray capable of obtaining centric relation through gothic arch tracing and a facial scan. By replacing the traditional complete denture restoration method, the number of patient visits was reduced and esthetic results with satisfactory denture support, retention, and stability were obtained. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of the concept of centric relation (CR) in dentistry. It explores the different definitions and controversies surrounding CR, emphasizing the lack of consensus in the field. The article emphasizes the importance of understanding CR in prosthetic rehabilitation and its impact on occlusion and temporomandibular joint (TMJ) health. It concludes by highlighting the need for a more specific and standardized terminology for describing CR. Overall, this text is a valuable resource for researchers and healthcare professionals seeking to understand the complexities of CR in dentistry. [Extracted from the article]

Background: Edentulous patients have poor neuromuscular proprioception to guide the mandible to the desirable horizontal relation. Horizontal jaw relation is a complex relationship in which variation may occur in vertical, anteroposterior and mediolateral directions. Objective: The aim of this study was to train the tongue and bring the mandible to centric relation in geriatric edentulous cases. Materials and Methods: Protrude the tongue to the maximum length and retract back to centric relation, move the tongue on the left side beyond the angle of the mouth and bringing back to centric relation, move the tongue on the right and left side beyond the angle of the mouth and bringing back to centric relation, then the tongue should move upwards and touches the marginal tubercle of upper lip and bringing back to centric relation and move the tongue upward and posteriorly to touch the posterior part of the hard palate of the maxilla and swallowing. Results: Edentulous patient can successfully move the mandible in centric relation after training the tongue. Conclusion: The present technique is useful for establishment of horizontal jaw relation in edentulous cases using tongue training exercise in Prosthodontic dentistry. [ABSTRACT FROM AUTHOR]

Objective: To describe a technique for fabricating an additively manufactured maxillary occlusal device using a complete digital workflow. Clinical Considerations: The maxillary occlusal device design may include an anterior platform to guide the positioning of the mandible in a reproducible position for facilitating the delivery procedure. Conclusions: The described technique provides a more efficient and less time‐consuming method for designing and manufacturing a printed occlusal device, when compared with conventional fabrication techniques. Clinical Significance: The additively manufactured occlusal device designed with an anterior platform guides the positioning of the mandible in a reproducible position, facilitates the delivery procedures, and produces a more efficient and less time‐consuming method when compared with conventional methods. [ABSTRACT FROM AUTHOR]

Purpose: To assess the reproducibility of four different centric relation (CR) recording techniques, and time spent performing each technique in edentulous individuals. Materials and methods: Four techniques were assessed: extraoral gothic arch (EOGA) tracing, intraoral gothic arch (IOGA) tracing, deglutition (D), and frontal manipulation with tongue elevation (FMTE). Twelve subjects participated in the study; four technique records were performed on each volunteer by the same operator. Each record was repeated three times, in the same period of the day, with a 30 min interval between each technique. The reproducibility of each technique was assessed by the tri‐dimensional displacement of the position of the condylar housing (mandible condyle) to the wall of the condylar guide (glenoid cavity) in the semi‐adjustable articulator (anteroposterior, mediolateral, and superior–inferior). The time spent on each technique was timed in seconds (from the beginning of each technique until the wax occlusion fixation). The analysis of variance (ANOVA) and the Tukey test were performed for anteroposterior displacement (two‐way) and for time spent on CT recording techniques (one‐way) (α < 0.05). Regarding mediolateral and superior–inferior displacements, the nonparametric Kruskal–Wallis was performed for the comparison between recording methods, whereas the Mann–Whitney test was performed for the comparison between sides (α < 0.05). Results: The factor recording technique interfered with the anteroposterior displacement (ANOVA: α < 0.001; F = 11.396). The technique D (right side: 3.78 ± 0.69 mm; left side: 3.45 ± 0.74 mm) showed a statistically significant difference compared to the other techniques (EOGA: right side: 3.00 ± 0.00 mm; left side: 3.00 ± 0.00 mm; FMTE: right side: 2.81 ± 0.52 mm; left side: 2.82 ± 0.79 mm; IOGA: right side: 2.90 ± 0.65 mm; left side: 3.12 ± 0.44 mm). The time spent on the recording technique influenced the results (ANOVA: α < 0.001; F = 21.118). The IOGA (340.40 ± 163.41 s) and EOGA (285.93 ± 133.84 s) required more time compared to the D (86.00 ± 34.33 s) and FMTE (101.33 ± 36.72 s) techniques. Conclusion: Graphic recordings showed better reproducibility and accuracy of the position of the centric relation. [ABSTRACT FROM AUTHOR]

Purpose: Centric relation (CR) is a universally recognized term and an acceptable reference position with a long history of success. The problem is that there is little consensus as to its definition or the method of recording it, and this has created an uprising to abolish it. Methods: A review of pertinent literature related to its definition, method of recording, anatomic considerations, and long‐standing principles was conducted. Results: Centric relation is an established term but there are valid concerns over its definition and method of recording. There is consensus on using it as a restorative position in a patient in need of full‐arch reconstruction, and there is no substantive clinical research to contradict this. If a clinician decides to use a different position, it should have a different name. Conclusions: Centric relation is a reproducible reference position that can be utilized for diagnostic and restorative dental procedures with substantial scientific evidence to support that premise. There are numerous well‐documented techniques, all of which are intermaxillary, that can replicate the position. There is little scientific evidence to support a premise as to where the exact position of the condyle should be in relation to the fossa. [ABSTRACT FROM AUTHOR]

Copyright of Fogorvosi Szemle is the property of Hungarian Dental Association 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.)

Introduction/Objective. Deprogramming of the neuromuscular system with the use of stabilization splint might provide more precise evaluation of the centric relation (CR) – maximum intercuspation (MI) discrepancy. The study aimed to evaluate the differences between the bite registrations obtained in the CR before and after the application of the stabilization splint therapy. Methods. The sample included 48 non-deprogrammed individuals without any apparent signs and symptoms of temporomandibular disorders (TMDs). The neuromuscular system was deprogrammed by employing stabilization splint therapy. A condylar displacement evaluation was performed on vertical, horizontal, and transverse planes of space, with the assistance of a condylar position indicator. Results. The mean values of condylar displacements, which were obtained after the deprogramming of the neuromuscular system, were significantly greater than those obtained before neuromuscular deprogramming for vertical condylar displacement (p < 0.0001). A greater degree of condylar distraction was observed on the left side of the vertical plane before (p < 0.01) and after neuromuscular deprogramming (p < 0.05). The highest level of condylar displacement occurred in the postero-inferior direction subsequent to the muscle deprogramming. Conclusion. It was observed that the level of average condylar displacements was significantly higher following the deprogramming of the neuromuscular system compared to that recorded before neuromuscular deprogramming using stabilization splint therapy. A more precise orthodontic diagnosis could have been obtained if the condyles were placed in a more exact CR position by muscle deprogramming.

Copyright of Manuelle Medizin is the property of Springer Nature 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.)

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]

Ethylene vinyl acetate mouthguards are the most often used custom protective intraoral appliances by combat sports practitioners. However, due to the difficulties in maintaining the hygiene of such mouthguards and thinning during fabrication, resulting in difficulty in predicting final dimensions, they may not be the optimal solution. The aim of this research was to evaluate an innovative method of mouthguard formation using intraoral modeling of the mouthguard pattern, hybrid acrylic material, and the addition of ZnO nanoparticles. Seventeen mouthguards patterns and 34 custom mouthguards were evaluated: 17 hybrid and 17 nanohybrid. A total of 1122 measurements were performed: each mouthguard and pattern was measured at 22 points. Statistical analyses were performed with the use of IBM® SPSS® Statistics 27.0.0 software (IBM, Armonk, NY USA). The mean thickness of the patterns and mouthguards at all labial areas of central incisors were between 4.65 and 4.80 mm. The thickness at the buccal surface of the first molar was between 3.71 and 4 mm, and at the occlusal surface between 3.40 and 3.56 mm in the cusp area. All measurements of hybrid and nanohybrid mouthguards were strongly and highly correlated with the measurements of the mouthguard patterns. Hybrid and nanohybrid mouthguards are an advantageous alternative to thermoformed custom appliances. [ABSTRACT FROM AUTHOR]

To determine the vertical dimension and centric relation during the construction of implant overdentures, the record base and wax rim may need to be adjusted. The conventional method has several drawbacks, as it requires repeated tightening and loosening of the impression coping. Here, we report a useful and novel method for interocclusal records using the healing abutments in implant overdentures. Our case demonstrates that this method is easier and simpler and prevents gingival collapse.

Introduction: incorporating functional aspects and the study of the temporomandibular joints (TMJ) to the orthodontic field, requires an initial examination of the TMJ, and from that position in centric relation (CR), make a diagnosis and plan the orthodontic treatment. Objective: to determine the possible association between slides from CR to the position of maximum intercuspation (PMI) with age, and to identify changes in occlusal variables as a consequence of the slide. Methods: a descriptive and correlational cross-sectional study was carried out, in the period from October 2018 to October 2019, at the Victoria de Santa Clara Teaching Clinic of Stomatological Specialties. An intentional, non-probabilistic sample of 30 young people between 15 and 19 years of age, with complete permanent dentition and abnormal sliding from RC to PMI, was formed. Occlusal variables were examined: projections, overhangs, relationship of molars and canines, dental midlines. Results: the mean of the magnitude of the anterior slip between CR and PMI showed a value of 1.53mm, highlighting adolescents of 15 years of age; while in the lateral slide the distribution behaved homogeneously. With a magnitude of 1 mm or more, the three mean values of overjets differed significantly, with p<0.05 in incisors and p<0.10 in canines. The right molar ratio changed significantly between CR and PMI, with p=0.046. Conclusions: the discrepancy between CR and PMI was not associated with age. Changes in occlusal variables confirm the importance of performing a correct occlusal examination for orthodontic diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Background: Currently, there is a lack of data relating to dental practitioners' habits with clinical occlusal assessment and the application of practical techniques in occlusion. Objectives: The aim of this study was to investigate habits with clinical occlusal assessment and the practical application of established concepts in occlusion amongst a cohort of international dentists. Methods: A piloted questionnaire with 20 statements was distributed by 5 recruiters. The recruiters were based in Malta (1), South Africa (1), Malaysia (1) and the UK (2). Outcomes were analysed using descriptives, chi‐squared and Fisher's exact test. All the analyses were carried out in Stata, Version 12. Significance was inferred at p <.05. Results: Four hundred thirty‐five completed responses were included in the sample (response rate, 70.7%). Overall, high levels of agreement were reported with the provision of single‐unit crown and onlay restorations (78.8%) and bridge prostheses (up to 3 units, 77.9%), respectively. One‐third (33.6%) agreed to observing dynamic occlusal relationships during an adult patient dental examination, 40.7% reported using articulators for crown and bridge cases, and 25.1% agreed to taking facebow records. Under half (47.3%) of the dentists expressed dissatisfaction with their undergraduate training in occlusion, with no significant association with the variables of the number of years of experience, the country of practice or being in general practice (p ≥.226). Conclusion: The results indicate a disparity between traditionally taught and applied concepts in clinical occlusion and the undertaking of occlusal assessments and the management of occlusion in clinical practice. [ABSTRACT FROM AUTHOR]

Copyright of Clinical Orthodontics is the property of Dental Press International 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.)

Copyright of Journal of Craniomandibular Function is the property of Quintessence Publishing Company Inc. 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: Digital systems including intraoral scanners (IOSs) and optical jaw tracking systems can be used to acquire the maxillomandibular relationship at the centric relation (CR). However, the discrepancy of the maxillomandibular relationship recorded at the CR position when using digital methods remains uncertain., Purpose: The purpose of this clinical study was to compare the accuracy of the maxillomandibular relationship recorded at the CR position using a conventional procedure, 4 different IOSs, and an optical jaw tracking system., Material and Methods: A completely dentate volunteer was selected. A Kois deprogrammer (KD) was fabricated. Six groups were created based on the technique used to obtain diagnostic casts and record the maxillomandibular relationship at the CR position: conventional procedures (CNV group), 4 IOS groups: TRIOS4 (TRIOS4 group), iTero Element 5D (iTero group), i700 wireless (i700 group), Primescan (Primescan group), and a jaw tracking system (Modjaw) (Modjaw group) (n=10). In the CNV group, conventional diagnostic stone casts were obtained. A facebow record was used to mount the maxillary cast on an articulator (Panadent). The KD was used to obtain a CR record for mounting the mandibular cast, and the mounted casts were digitized by using a scanner (T710) to acquire the reference scans. In the TRIOS group, intraoral scans were obtained and duplicated 10 times. The KD was used to obtain a bilateral virtual occlusal record at the CR position. To acquire the specimens of the iTero, i700, and Primescan groups, the procedures in the TRIOS4 group were followed, but with the corresponding IOS. In the Modjaw group, the KD was used to record and export the maxillomandibular relationship at the CR position. Articulated virtual casts of each group were exported. Thirty-six interlandmark linear measurements were computed on both the reference and experimental scans. The distances obtained on the reference scan were used to calculate the discrepancies with the distances obtained on each experimental scan. The data were analyzed by using 1-way ANOVA followed by the pairwise comparison Tukey tests (α=.05)., Results: The trueness and precision of the maxillomandibular relationship record were significantly affected by the technique used (P<.001). The maxillomandibular relationship trueness values from high to low were iTero (0.14 ±0.09 mm), followed by the Modjaw (0.20 ±0.04 mm) and the TRIOS4 (0.22 ±0.09 mm) groups. However, the iTero, Modjaw, and TRIOS4 groups were not significantly different from each other (P>.05). The i700 group obtained the lowest trueness and precision values (0.40 ±0.22 mm) of all groups tested, followed by the Primescan grop (0.26±0.13 mm); however, the i700 and Primescan groups had significantly lower trueness and precision than only the iTero group (P<.05)., Conclusions: The trueness and precision of the maxillomandibular relationship recorded at the CR position were influenced by the different digital techniques tested., (Copyright © 2022 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Aim: The objective of the present article is to demonstrate the digital workflow used to manufacture an adjusted oral splint in a patient case., Materials and Methods: A 25-year-old female patient presented for management of her bruxism. Therefore, an adjusted oral splint was manufactured. A computer-aided motion analysis of the patient was conducted (JMA Optic). Full-arch scans of the maxilla and mandible, a biocopy of the maxilla with a bite fork, and buccal scans of the centric jaw relation (Primescan) were performed. The jaw relation was determined beforehand by ballistic closing on a chairside-fabricated anterior jig. The digital construction of a Michigan splint took place in the dental laboratory. The design was nested and milled from a polymethyl methacrylate (PMMA)-containing blank (CLEARsplint Disc)., Results: The oral splint was inserted into the patient's mouth and checked to ensure a tension-free fit. The static and dynamic contact relationship was checked. During the follow-up visit, the patient reported an improvement in tension in the masticatory muscles., Conclusion: The described procedure allows for the manufacture of an adjusted oral splint through a purely digital workflow.

Centric relation (CR) was used in the complete dentures for edentulous jaws firstly. Then, CR was gradually applied in the clinical diagnosis and treatment of dentate jaws. Regarding the application of CR in dentate jaws, there are many doubts about its rationality. For instance, should CR be the core of diagnosis and treatment of temporomandibular disorders? Should CR be used as the jaw position of establishing occlusion in occlusal reconstruction? Should CR serve as the target jaw position in orthodontic treatment? Meanwhile, varieties of CR clinical applications are objective. According to the existing evidence, this paper summarizes the applicable conditions of several main clinical situations with little controversy. We preliminarily put forward the decision tree for the clinical application of CR, which can be used as a reference in clinical practice.

Introduction: There are numerous methods to guide the mandible into Centric Relation (CR). The Dawson's bimanual technique is a time tested and established method to guide the mandible into CR. On the other hand the author of this study also has copyrighted a technique (wax ball orientation technique©) to guide the mandible into CR. Hence, this methodological study was performed to compare the two CR techniques to guide the mandible in CR position using clinical, myographical and radiological assessment methods. Aim: To compare and assess which amongst the two (Dawson's bimanual technique and wax ball orientation technique) CR guiding techniques best guides the mandible to CR position using clinical, electromyographical and radiological assessment methods. Materials and Methods: This interventional and clinical study was conducted at School of Dental Sciences, KIMSDU, Karad, Maharashtra, India, from May 2019 to May 2020. The study included healthy dentate individuals having Angle's class I malocclusion without any occlusal interferences and an intact dentition except for 3rd molars. Two CR technique to guide the mandible were technique 1-Dawson's bimanual technique and technique 2 - wax ball orientation technique. The study was carried out in three phases: clinical, electromyographical and radiological. Difference between the centric points, workload on elevators, condylar position was statistically analysed. Descriptive statistics was used to analyse the difference between the centric points marked using both the techniques. Independent t-test was applied to compare the gender and the mean centric distribution. Results: Among the 45 study subjects considered for the study, 32 were females and 13 were males with the mean age of 21 years. No statistically significance difference was observed between the two techniques. Paired t-test showed that workload on elevators of both sides, Right Masseter in technique 1 and 2 had p-value= 0.088, left Masseter in technique 1 and 2 had p-value= 0.3, Right temporalis in technique 1 and 2 had p-value= 0.463, left temporalis in technique 1 and 2 had p-value= 0.429. There was difference between the Anteroposterior (AP) and Superoinferior (SI) position of condyle in relation to the fossa. AP measurement in the right side in tech 1 and 2 with p-value= 0.448, AP measurement in the left side in tech 1 and 2 with p-value= 0.178, SI measurement in the right side in tech 1 and 2 had p-value= 0.803, SI measurement in the left side in tech 1 and 2 had p-value= 0.259, which were statistically insignificant. Multivariate test showed statistically significant difference between gender and EMG, results whereas it was insignificant in Magnetic Resonance Imaging (MRI). Conclusion: The wax ball technique has similar accuracy as the Dawson's Bimanual technique. [ABSTRACT FROM AUTHOR]

Introduction: There are numerous methods to guide the mandible into Centric Relation (CR). The Dawson's bimanual technique is a time tested and established method to guide the mandible into CR. On the other hand the author of this study also has copyrighted a technique (wax ball orientation technique©) to guide the mandible into CR. Hence, this methodological study was performed to compare the two CR techniques to guide the mandible in CR position using clinical, myographical and radiological assessment methods. Aim: To compare and assess which amongst the two (Dawson's bimanual technique and wax ball orientation technique) CR guiding techniques best guides the mandible to CR position using clinical, electromyographical and radiological assessment methods. Materials and Methods: This interventional and clinical study was conducted at School of Dental Sciences, KIMSDU, Karad, Maharashtra, India, from May 2019 to May 2020. The study included healthy dentate individuals having Angle's class I malocclusion without any occlusal interferences and an intact dentition except for 3rd molars. Two CR technique to guide the mandible were technique 1-Dawson's bimanual technique and technique 2 - wax ball orientation technique. The study was carried out in three phases: clinical, electromyographical and radiological. Difference between the centric points, workload on elevators, condylar position was statistically analysed. Descriptive statistics was used to analyse the difference between the centric points marked using both the techniques. Independent t-test was applied to compare the gender and the mean centric distribution. Results: Among the 45 study subjects considered for the study, 32 were females and 13 were males with the mean age of 21 years. No statistically significance difference was observed between the two techniques. Paired t-test showed that workload on elevators of both sides, Right Masseter in technique 1 and 2 had p-value= 0.088, left Masseter in technique 1 and 2 had p-value= 0.3, Right temporalis in technique 1 and 2 had p-value= 0.463, left temporalis in technique 1 and 2 had p-value= 0.429. There was difference between the Anteroposterior (AP) and Superoinferior (SI) position of condyle in relation to the fossa. AP measurement in the right side in tech 1 and 2 with p-value= 0.448, AP measurement in the left side in tech 1 and 2 with p-value= 0.178, SI measurement in the right side in tech 1 and 2 had p-value= 0.803, SI measurement in the left side in tech 1 and 2 had p-value= 0.259, which were statistically insignificant. Multivariate test showed statistically significant difference between gender and EMG, results whereas it was insignificant in Magnetic Resonance Imaging (MRI). Conclusion: The wax ball technique has similar accuracy as the Dawson's Bimanual technique. [ABSTRACT FROM AUTHOR]

Introduction: There are numerous methods to guide the mandible into Centric Relation (CR). The Dawson’s bimanual technique is a time tested and established method to guide the mandible into CR. On the other hand the author of the present study also has copyrighted a technique (wax ball orientation technique©) to guide the mandible into CR. Hence, this methodological study was performed to compare the two CR techniques to guide the mandible in CR position using clinical, myographical and radiological assessment methods. Aim: To compare and assess which amongst the two (Dawson’s bimanual techniques, and wax ball orientation technique) CR guiding techniques best guides the mandible to CR position using clinical, electromyographical and radiological assessment methods. Materials and Methods: This interventional and clinical study was conducted at School of Dental Sciences, KIMSDU, Karad, Maharashtra, India, from May 2019 to May 2020. The study included healthy dentate individuals having Angle’s class I malocclusion without any occlusal interferences and an intact dentition except for 3rd molars. Two CR technique to guide the mandible were technique 1-Dawson’s bimanual technique and technique 2- wax ball orientation technique. The study was carried out in three phases: clinical, electromyographical and radiological. Difference between the centric points, workload on elevators, condylar position was statistically analysed. Descriptive statistics was used to analyse the difference between the centric points marked using both the techniques. Independent t-test was applied to compare the gender and the mean centric distribution. Results: Among the 45 study subjects considered for the study, 32 were females and 13 were males with the mean age of 21 years. No statistically significance difference was observed between the two techniques. Paired t-test showed that workload on elevators of both sides, Right Masseter in technique 1 and 2 had p-value=0.088, left Masseter in technique 1 and 2 had p-value=0.3, Right temporalis in technique 1 and 2 had p-value=0.463, left temporalis in technique 1 and 2 had p-value=0.429. There was difference between the Anteroposterior (AP) and Superoinferior (SI) position of condyle in relation to the fossa. AP measurement in the right side in tech 1 and 2 with p-value=0.448, AP measurement in the left side in tech 1 and 2 with p-value=0.178, SI measurement in the right side in tech 1 and 2 had p-value=0.803, SI measurement in the left side in tech 1 and 2 had p-value=0.259, which were statistically insignificant. Multivariate test showed statistically significant difference between gender and EMG, results whereas it was insignificant in Magnetic Resonance Imaging (MRI). Conclusion: The wax ball technique has similar accuracy as the Dawson’s Bimanual technique.

Multiple tooth loss can cause disharmonious occlusial plane, loss of vertical dimension and deflection of mandibular movement. Therefore, restoring proper vertical dimension and occlusion in the centric relation is an important treatment goal. Implant-assisted removable partial denture is a recently used clinical technique, because it increases patient satisfaction by improving retention, support, and stability of conventional denture. The objective of this article is to present a case report describing the fabrication of treatment denture and implant assisted removable partial denture using previously placed implants for a patient with partial loss of posterior support and anterior stop. [ABSTRACT FROM AUTHOR]

Aim: To investigate the electromyographic activity of masseter and temporalis muscles in full dentate participants after deprogramming with various muscle deprogramming devices (MDDs). Materials and Methods: The current study was a randomized crossover clinical trial. After the screening of 96 individuals, 30 participants were included based on the eligibility criteria. Surface electromyographic (SEMG) activity of masseter and temporalis muscles was analyzed in different clinical conditions: Condition A--at rest without muscle deprogramming, Condition B--after clenching without muscle deprogramming, Condition C--subsequent to 30 min of deprogramming by cotton rolls, Condition D--subsequent to 30 min of deprogramming by Leaf gauge, Condition E--subsequent to 30 min of deprogramming by Lucia jig, Condition F--subsequent to 24 h of deprogramming by Kois deprogrammer. The inter-group comparison was performed using the analysis of variance (ANOVA) test, and the pairwise comparison was done using Bonferroni post hoc test. Results: ANOVA showed a statistical significant difference in the electromyographic activity of masseter and temporalis muscles in tested individuals, subsequent to deprogramming with different MDDs. Between the tested MDDs, the lowest mean muscle activity was reported with the Kois deprogrammer and the highest with cotton rolls, when used for deprogramming. Conclusion: Muscle deprogramming with the Kois deprogrammer presented lowest muscle activity in both masseter and temporalis muscles involving both sides, thus confirming its effectiveness in achieving patient's centric relation position. [ABSTRACT FROM AUTHOR]

A technique for fabricating an additively manufactured Kois deprogrammer is described from the initial patient data collection with an intraoral scanner to the 3D printing methods to fabricate the device. The incorporation of digital technologies for manufacturing a Kois deprogrammer provides new clinical and manufacturing tools, providing more efficient and less time-consuming design and manufacturing techniques than conventional techniques while maintaining conventional prosthodontic concepts., (Copyright © 2022 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Purpose of the article: Centric relation is a dental term that has undergone many alterations over the years, which in turn have led to significant clinical controversies. These continuing changes in the meaning of the term CR have not only led to confusion, but they also have resulted in a variety of unnecessary diagnostic and therapeutic procedures. Analysis of the dental literature reveals ongoing misunderstanding and disagreement regarding that term among both clinicians and academic dentists. Materials and methods: A search of the PubMed database was performed with the following search terms: "centric relation", "masticatory muscles", "maxillomandibular relationship" and "condylar position." Relevant literature from the past 70 years until the present day was meticulously scrutinised. Results: As expected, the literature review on the topic of CR revealed a problematic pattern of changing definitions and clinical disagreements, all of which have had a significant impact on the practice of dentistry. Conclusion: There are semantic, conceptual and practical reasons for concluding that the term 'centric relation' is flawed. Those flaws have a significant impact on dental practice. Based on our analysis, argumentation is provided to conclude that the term 'centric relation' should be abandoned. Instead, it appears that every individual has a unique temporomandibular joint relationship which cannot be described by any singular term. In healthy dentate patients, this relationship is determined by the maximum intercuspation of the teeth and should therefore be considered as biologically acceptable. [ABSTRACT FROM AUTHOR]

Our goal is to show that temporomandibular disorder (TMD) patients with orthopaedic instability can be effectively treated by the combination of occlusal splint therapy and molar intrusion. Diagnostic records of 18 patients reporting previous TMD and treated with splint therapy were evaluated. Postsplint anterior open bite was treated by skeletally anchored molar intrusion. Changes in overjet (OJ), overbite (OB) were measured on articulator mounted models: initially in maximal intercuspidation (MI), centric "de jour", postsplint centric relation (CR) and postintrusion CR. Changes in ANB (A point-Nasion-B point) angle, mandibular plane–palatal plane angle and facial axis angle were assessed on lateral cephalograms. Morphological changes of the condyle were detected on pre-and posttreatment CBCT images. When compared screening mountings to MI models, significant differences were found in OJ and OB. Following splint wear, there was a significant increase in lower facial height and significant decrease in facial axis angle, which in turn increased ANB angle. OB and OJ showed a significant change on the postsplint mountings when compared to MI. After intrusion, mandible exhibited counterclockwise rotation, which decreased lower facial height, increased OB and facial axis angle and decreased ANB and OJ. Posttreatment CBCTs confirmed improved condylar morphology.Occlusal splint therapy followed by orthodontic molar intrusion provides MI-CR harmony, therefore, it seems to be an effective method for treating TMD patients. [ABSTRACT FROM AUTHOR]