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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.)

To present a case report of an orthodontic treatment of a high-angle, dual bite, Class II malocclusion without extractions and with the use of mini-plates. Class II malocclusion treatment protocols vary according to the morphological component of the malocclusion and the magnitude and direction of craniofacial growth. It is generally agreed that the cooperation of the patient and careful planning of anchorage are the key determinants of successful treatment. Protrusion of the upper and lower lip and a retrognathic mandible were the patient’s chief concerns. The patient had learned to project her mandible forward to disguise the overjet. The patient’s parents elected to correct the malocclusion with the use of bilateral infrazygomatic mini-plates. Pre-treatment condylar stabilization with an orthotic established a stable centric relation position, followed by mounting of the models on a semi-adjustable Panadent articulator. This allowed diagnosis and treatment planning from a stable condylar position and eliminated possible misdiagnosis due to the dual bite. Distal retraction and vertical control of the upper teeth enabled correction of the Class II malocclusion with minimal patient cooperation. Mini-plate-assisted treatment corrected the excessive overbite and overjet. The patient completed treatment with a stable occlusion and no longer postured her jaw forward. The parents and patient were completely satisfied with the positive treatment outcome. A 2-year follow-up confirmed the clinical stability.

Aim: The purpose of the study is to evaluate and compare the horizontal mandibular positions recorded between intraoral conventional tracer and intraoral digital tracer in upright and supine position. Materials and Methods: Twenty-four edentulous patients with well-formed ridge and adequate interarch distance space were selected. MATLAB software was assimilated with intraoral digital tracer and was utilized in the study for recording the horizontal movements of the mandible, i.e., gothic arch tracing by intraoral digital tracer and was observed on a laptop with the help of MATLAB Software. For each subject, multiple mandibular readings were recorded and analyzed through software, and similar readings were recorded with conventional intraoral tracers. The comparison between intraoral conventional tracer and intraoral digital tracer was done to assess the reliability. Moreover, the consistency of recording horizontal mandibular position was also compared between upright and supine position. Results: The data were procured and utilized in comparison for different positions revealed statistically significant difference by using Student's Paired t-test. The test resulted in supine position better compared to upright position (P = 0.0001). The association between supine position with upright position was calculated using Fischer's exact test, and it was also found to be statistically significant (P = 0.002). The Pearson's Correlation analysis was performed to check the agreement between upright and supine position and very weak downhill correlation (r2= −0.130) was observed between the two variables. Conclusion: On evaluation and comparison of horizontal mandibular position, it was found that the intraoral digital tracing technique is more valid compared to conventional intraoral tracer technique. It was also observed that the consistency of reproducibility in recording horizontal mandibular position in supine position is significantly higher than upright position.

Aim: The aim and objectives of this study were to assess and compare the efficacy of a new copyrighted technique (wax ball technique, L-77997/2018) and design (denture base design for the wax ball technique, L-78006/2018) for recording centric relation (CR). Settings and Designs: In vivo – comparative study. Materials and Methods: This study was conducted on sixty consented edentulous patients. The study participants were divided into Group I and Group II. CR in Group I patients was recorded using Dawson's bimanual technique (technique 1). For participants in Group II, CR was recorded using the authors' copyrighted technique (technique 2). Time taken and accuracy of CR records by both the techniques were evaluated. Statistical Analysis Used: Descriptive statistics such as frequency and percentage were calculated for categorical variables, mean and standard deviation were calculated for quantitative variables. Independent t-test was used to compare the time taken to record the CR between the two groups. The accuracy of both the techniques was assessed by Mann–Whitney U-test. Results: The mean time taken for technique 1 was 56.47 s, whereas for technique 2, it was 5.97 s, with an overall mean difference of 50.5 s between the two techniques. Both techniques were found to be accurate, as the CR recorded during jaw relation matched with CR during trial in all the cases in both the groups (frequency 30 (N) and cumulative percentage 100%). Conclusion: From the study, it was found that, time taken for technique 2 was statistically less compared to that of technique 1, and both the techniques were found to be equally accurate.

Occlusal interference causes instability in temporomandibular joint and hyperactivity of mastication muscles which eventually leads to temporomandibular joint dysfunction. Therefore, achieving stable occlusion is important in young patients. It is key factor in optimizing functional occlusion in adulthood. Application of «The ABO Model Grading System» and Mandibular Position Indicator as an additional diagnostic method in children undergoing orthodontic treatment using braces. Thirty-two patients aged 14 to 18 diagnosed with teeth crowding on the upper and lower jaws were examined, then separated in two groups of 16 people each. All patients underwent orthodontic treatment using braces. In group 2, due to application the anthropometrical system of quantitative evaluation ABO with re-fixing the incorrectly arranged braces by indirect bonding method, occlusal interferences were eliminated. MPI analysis showed discrepancy between the central occlusion and the central relation which was not as relevant as in the group 1 (p > 0.05). Using the anthropometric system of quantitative assessment of ABO with subsequent re-fixation of incorrectly placed braces by indirect bonding, effectively improves the MPI. This determines the unity of position between articular condyles on the lower jaw in the centric occlusion and in the centric relation, which allows to get a stable result of orthodontic treatment. [ABSTRACT FROM AUTHOR]

Recording the jaw relations is a critical step during the fabrication of complete dentures. Both vertical and horizontal relations must be correctly established to ensure efficient function of the complete dentures with the least amount of trauma to the supporting tissues and temporomandibular joints (TMJs). The aim of this review was to collect comprehensive data about the most recommended methods for determining the optimal vertical dimension of occlusion (VDO) during the fabrication of complete dentures and to determine whether and/or to what extent these methods respect the correct spatial relations in TMJs. An electronic search through the PubMed, Web of Science, OVID, SCOPUS and EBSCO search engines selected 111 references from peer-reviewed journals, which met the inclusion criteria for this literature review. The single, exclusive and scientifically confirmed consensus for the determination of both the VDO and centric relation during complete denture fabrication is still lacking. Authors agree that the establishment of an incorrect relation between the maxilla and mandible causes severe, mostly harmful consequences in the stomatognathic system. So far the available procedures are associated with a high degree of subjective clinical judgements and variability. Thus, ongoing studies with the application of new technologies are still current and strongly recommended. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this Best Evidence Consensus Statement was to evaluate the existing literature relative to two focus questions: What are the techniques used and their reproducibility in recording centric relation (CR) in a dentate and partially dentate population and what effect do different recording materials have on the reproducibility of CR? Materials and Methods: Keywords used in the initial search were: CR, interocclusal records, CR accuracy, CR reproducibility, and CR technique. The search was then limited to Systematic Reviews, Randomized Controlled Studies, Meta‐analyses, and Clinical Trials. Results: Initial search related to the selected search terms resulted in more than 3500 articles. When subsequent search was limited to Systematic Reviews, Randomized Controlled Studies, and Meta‐Analysis and Clinical Trials, this resulted in 291 articles selected for further analysis. Conclusions: Techniques using chin point guidance, bimanual manipulation, power centric, Gothic arch tracing, leaf gauge, and anterior deprogramming devices to record CR can all be comparable in precision and clinical accuracy in regards to clinical relevance. Practitioner experience and familiarity with a particular technique is critical for accuracy when recording CR. Polyvinyl siloxane and polyether consistently performed better in the broad range of studies on recording materials. Virtual capture of CR could serve as a comparable recording medium but requires further clinical study. [ABSTRACT FROM AUTHOR]

Purpose: This Best Evidence Consensus Statement evaluated the existing Angle's classification clinical literature to determine if the Angle's classification as historically determined in maximum intercuspal position (MIP) with hand held casts is coincident with the centric occlusion (CO) determined Angle's classification. In addition, it explored the value of using Angle's classification for edentulous patients Materials and methods: The search strategy was related to the focus questions and limited to Meta‐analyses, Systematic Reviews (SR), Randomized Controlled Trials (RCT) and Clinical Trials. Searches were completed using the term Angle's classification and Boolean Modifiers (AND) with the key terms: dental occlusion, dental occlusion centric, centric occlusion, centric relation, maximal intercuspation, MIP, intercuspal position, and edentulous patient, retrognathia, determination, and prognathia. Additional related articles were culled from the reference lists in the articles found in the PubMed searches. Results: The search identified 494 articles related to the selected terminology. Titles were reviewed and selected if related to the focus questions for further review. Seven papers could be identified that addressed the specifics of the questions. Conclusions: There is evidence that the Angle's classification for many patients will change when recorded in CO compared to the historical MIP determination/definition. A different Angle's classification recorded in CO is potentially a significant diagnostic finding for patients needing complete mouth rehabilitation. The current definitions of Angle's Classification are not useful in the management of edentulous patients. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this Best Evidence Consensus Statement was to evaluate the existing literature relative to two focus questions: How often does centric occlusion coincide with maximal intercuspal position in dentate and partially dentate populations?; and should centric occlusion or maximal intercuspal positions be equivalent for dentate and partially dentate patients undergoing complete mouth rehabilitation? Materials and Methods: Keywords used in the initial search were: intercuspal position, centric occlusion, centric relation, maximal intercuspal position, prosthodontic rehabilitation, and occlusion. The search was then limited to Systematic Reviews, Randomized Controlled Studies, Meta‐analyses and Clinical Trials. Results: The initial search strategy related to the selected search terms resulted in more than 15,000 articles. When the subsequent search was limited to Systematic Reviews, Randomized Controlled Studies, and Meta‐Analysis and Clinical Trials, 313 articles were selected for further analysis. Conclusions: Review of the literature reveals that most dentate and partially dentate patients do not have coincident centric occlusion and maximal intercuspal position. There is support for coincidence between centric occlusion and maximal intercuspal position as the preferred occlusal relationship in complete mouth rehabilitations. The literature does not report conclusive evidence of adverse prosthodontic outcomes with complete rehabilitations in centric occlusion or maximal intercuspal position in a healthy population. However, there is support for an association between centric occlusion‐maximal intercuspal position discrepancies and occlusal instability as well as temporomandibular joint disorders. Hence, it is concluded that partially and completely dentate patients requiring complete mouth rehabilitation should be restored in centric occlusion. [ABSTRACT FROM AUTHOR]

Copyright of Acta Odontologica Latinoamericana: AOL is the property of Acta Odontologica Latinoamericana 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.)

Mounting dental casts in an articulator is an important prerequisite for prosthodontic rehabilitation cases where the design of an accurate static and dynamic occlusion is needed. Virtual mounting can be achieved through the superimposition of various 3D images acquired from the hard and soft tissues of the patient. The purpose of this technical report is to describe a digital cross‐mounting technique for patients undergoing implant‐supported fixed prosthetic treatment. Through the use of face scanning, intraoral scanning, and cone beam computed tomography, this technique enables creation of a 3D virtual patient with occlusal registration in centric relation. Ultimately, the described methodology allows for the fabrication of definitive full‐mouth implant‐supported fixed prostheses. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate reproducibility of the position of centric relation in patients with disc displacement with reduction. Materials and methods: The test group included 30 subjects, diagnosed with disc displacement with reduction in right, left or both joints. The control group included 12 individuals with no signs and symptoms of temporomandibular disorders. Using chin point guidance with a jig, centric relation record was made three times by every participant, in a single session. Left and right condylar position for each centric relation record was determined and recorded using the electronic ultrasonic measuring device. The data were transferred to the computer, processed and analyzed. Condylar distances between centric relation records were measured (anteroposterior, vertical, transversal and linear values), and the data were statistically analyzed using the t and the F tests. Results: No statically significant difference was found between the test and the control groups. Two thirds of study participants demonstrated condylar position of the repeated centric relation recording within the area of 0.3 mm in diameter. For more than 90% of participants that area was within 0.4 mm. Conclusions: There is no difference in reproducibility of the centric relation between patients with disc displacement with reduction and healthy temporomandibular joint individuals (p>0.05). When doing centric relation record on a patient with disc displacement with reduction there is no need for previous splint therapy and standard precautions are acceptable. The obtained results must be interpreted within the experimental group, and not projected on the other groups of temporomandibular disorders.

The Central Relation (CR) is a concept that defines the ideal position of the mandibular condyle in the mandibular fossa. The position has been the subject of much discussion in the literature, noting changes as advancements in knowledge and technology are achieved. Thus, certain essential anatomical elements that are used as a guide for the clinician, are taken into account. The importance of being able to identify this position lies in the correct execution of both diagnostic and treatment procedures in various areas of dentistry. There are anatomical elements of the temporomandibular joint (TMJ) that improve understanding of the CR concept. These include: Bone condensation of the functional articular surfaces and their fibrocartilage coating; the middle portion of the joint disc, devoid of vessels and nerves. The roof of the mandibular fossa can become extremely thin, so it would not be considered an area to support load; the posterior prolongation of the articular disc (AD) Which is highly vascularized and innervated. The AD is also closely related to structures such as the temporomandibular or lateral ligament and the superior head of the lateral pterygoid muscle. Along with the previously described elements, this would allow proper functioning of the TMJ. The correct learning and use of these concepts contributes to a better exercise in the professional development of students and professionals in the area of dentistry. [ABSTRACT FROM AUTHOR]

Incorrect registration of the condylar position in orthognathic surgery is supposed to cause postoperative relapse, condylar resorption and temporomandibular disorders. The aim of this prospective study was to evaluate the influence of general anaesthesia on centric relation (CR). Therefore, CR registered preoperatively in the awake patient and CR registered intraoperatively under general anaesthesia were recorded in 30 patients (14 men, 16 women) undergoing orthognathic surgery (skeletal class I: n = 3, II: n = 13, III: n = 14; symmetric: n = 20; asymmetric: n = 10). CR records were digitized and, through superimposition on the preoperative cone beam computed tomography of the patient's skull, the superior, anterior and posterior joint space and the volumetric congruence of 120 condyles were analysed. The linear measurements of joint spaces did not demonstrate any clinically relevant discrepancy between the CR measured in the awake and anaesthetized patient. In contrast, volumetric analysis revealed statistically significant differences between both states, with an intraoperative condylar sag predominantly in the posterior–inferior direction. The patient's skeletal class or symmetry had no significant influence on the intraoperative condylar displacement. Thus, the risk of fixing the condyle in an unphysiological position supports the idea of using intraoperative condylar positioning devices to achieve predictable and stable outcomes. [ABSTRACT FROM AUTHOR]

After over 80 years of much obsession as well as avoidance of the subject of temporomandibular disorders (TMDs), the dental profession is still divided over what they are and how to deal with them. Over this period, nearly every discipline in dentistry has played some role in the development of this field. Unfortunately, a significant amount of this information has been based on personal opinion, experience-based philosophies, or poorly conducted research. Furthermore, each dental specialty has been responsible for contributing to the concepts of the etiology and management of TMDs with their own professional bias; for example, orthodontists describe these problems in orthodontic terms and offer orthodontic treatments or solutions for their patients. As various treatment approaches were found to be effective at least some of the time, this has further led to misinformation and confusion within the profession. Advances in research from diverse fields, including neurophysiology, pain pathophysiology, genetics, endocrinology, behavioral sciences, and psychology, have significantly altered our understanding of TMDs and how they should be managed. The rigid mechanical and dental-based model of the past has been gradually replaced by a biopsychosocial medical model for the diagnosis and treatment of TMDs as well as other acute and chronic pain disorders. This paper discusses the evolution of our understanding of TMDs since they were first described 85 years ago. Contemporary scientific findings and their implications are presented in some detail for clinicians who wish to provide the appropriate management for their orofacial pain patients. [ABSTRACT FROM AUTHOR]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana 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: When degree of facial asymmetry is noticeable, it negatively affects facial and smile esthetics. It may due to discrepancies in size and position between cranial base and maxilla/mandible. Asymmetry due to occlusal interference may result in functional shift of the mandible which usually poses a challenge. So diagnosis and functional examination are keys to an esthetic and stable outcome. Objectives: This case report addresses the facial asymmetry in an adult patient who sought for improvement infacial appearance and occlusion. Case Description: A 26-year old male patient reported with chief complaint of noticeable facial asymmetry and irregularly positioned teeth. Clinical examination revealed mild facial asymmetry. Intraorally patient showed crowding, non-coincident dental midlines, anterior cross bite, missing 23 and root stump 46. Starting point in diagnosis and treatment of this case was establishing centric relation through guiding the mandible into centric relation rather than centric occlusion. During functional examination we observed discrepancyin CR-CO which was confirmed using PA-Ceph in centric rest position. Treatment was planned as deprogramming splint followed by fixed mechanotherapy. Post muscle deprogramming we were able to achieve "true" anatomic relationship of the mandible to the maxilla. Conclusion: Thus, the present case report aims at addressing important aspect of functional examination to be considered by the orthodontist while reaching an accurate diagnosis and treatment plan in such patient's with challenging asymmetry. [ABSTRACT FROM AUTHOR]

Introduction. The objectives of this study were to assess the relationship between centric relation-habitual occlusion discrepancy and temporomandibular disorder symptoms, the spatial planes in which the discrepancy is encountered and the correlation between gender and muscle pain. Materials and methods. Thirty subjects (14 females, 16 males), aged between 20-30 years, were clinically evaluated, as follows: muscle (temporalis, masseter, lateral and medial pterygoid) and temporomandibular joint examination, occlusal (static and dynamic) relationships, centric relation. Casts were mounted in centric relation using an articulator and then three-dimensionally analyzed. Results and discussion. Muscle pain was found in 57.14% females and 37.5% males. Discrepancy was higher in subjects with pain in all planes (transversal 0.92 mm vs. 0.26 mm [correlation coefficient=0.897]; sagittal 0.94 mm vs. 0.85 mm [correlation coefficient=0.249]; vertical 1.15 mm vs. 0.36 mm [correlation coefficient=0.504]) and similar in males and females. Conclusions. Transversal discrepancy was associated with muscle pain. Muscle pain and discrepancy were not correlated with gender. [ABSTRACT FROM AUTHOR]

Introduction: In the fields of Prosthodontics and dental occlusion, in particular, the idea of centric relation is important. It describes the position of the mandible in the temporomandibular joint with the disc appropriately positioned between the condyles when they are at their most superior and anterior positions against the articular eminence. In a situation of severe tooth wear requiring extensive restorative therapy, which included full rehabilitation at an enhanced vertical dimension of occlusion, this case study highlights the need of centric relation recording. Centric relation recording techniques remain relevant in contemporary dentistry, offering dentists the opportunity to improve treatment outcomes and diagnostic precision. Case Report: For a 45-year-old patient with significant and uneven dentition wear, this case study offers a thorough procedure for enhancing both function and appearance. The process was centred on restoring the patient's stability and occlusal function in the proper centric position. An assisted centric relation recording using JIG Lucia was used to create a full occlusal splint for muscle relaxation. After 2 months of wearing it at night and after 2 weeks of check-ups, the certified centric position was used to mount the models into the semi-adjustable articulator to design an analogue bimaxillary wax-up. The waxup was tested as a mock-up. After validation, twenty-two tooth-supported monolithic zirconia restorations and four implant- supported monolithic zirconia restorations were placed. Discussions : Both modifications produced a good blend of appearance and function. Together with an appealing integration of restorations, marginal fit, insertion, and centric occlusal contacts were accomplished. Occlusion both static and dynamic was possible with both restoration strategies.. Conclusions: Using fitted models in the correct hinge axis position guided by centric relation accurate recording, severe dental wear can be addressed. In modern dentistry, this method improves diagnosis precision and treatment outcomes. [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.

Digital or CAD/CAM workflows and protocols are being increasingly utilized because of their improved efficiency and reproducibility. For the fabrication of complete dentures, digital workflows can reduce treatment time and clinical visits while enhancing the reliability and reproducibility of the laboratory phase and materials. However, establishing centric relation (CR) and vertical dimension of occlusion (VDO) in a reproducible way is still a challenging step for complete denture fabrication in both analog and digital workflows. This clinical report describes a digital workflow using an individualized gothic arch tracing device (GATD) with open-source software for the fabrication of complete dentures. With this workflow, clinicians can offer customized solutions according to patient rehabilitation, with good reproducibility using gothic arch tracing to be implemented in the digital workflow.

In recent years, tooth wear has been a growing concern in dentistry as it has become increasingly prevalent among the population. At the same time, the development of adhesive techniques has enabled minimally invasive treatment protocols, with the goal of preserving and protecting teeth for as long as possible. This clinical report presents the case of a full-mouth rehabilitation patient with tooth wear who was treated using minimally invasive techniques. Esthetic and functional outcomes were designed and monitored using digital tools such as digital impressions, 3D facial scans, a digital tooth library, transcutaneous electrical nerve stimulation (TENS), MRI, and kinesiographic (KS) analysis throughout the treatment. To increase the vertical dimension of occlusion, instead of using traditional centric relation (CR) methods, a myocentric relation (MCR) technique was employed. This approach allowed the clinician to maintain the occlusal Class I situation, avoiding more invasive orthodontic treatment or maxillofacial surgery and resulting in reduced morbidity, treatment time, and cost for the patient. At the 1-year follow-up, good patient adaptation was shown, suggesting that the MCR concept is a viable alternative to conventional CR methods in appropriate cases.

Objective: In many esthetic treatments, clinicians may consider the option to modify the maxillo mandibular position. A raise of the vertical dimension of occlusion (VDO) may help restore esthetics, increase the space for dental materials, and reduce the invasiveness of dental procedures. Traditionally, VDO increases are done by using the centric relation (CR) position. Despite a long history of use, the neuromuscular effects of different maxillo mandibular relations are not fully studied. The aim of this study was to investigate the effect of alterations of maxillo-mandibular relation from maximal intercuspal position (MIP) to a raised VDO CR position on jaw-elevator muscle activity., Materials and Methods: Fifteen healthy individuals were asked to carry out maximal voluntary clenching (MVC) in MIP and in CR on individual splints. Electromyographic (EMG) activity of the masseter and anterior temporalis muscles was assessed in μV as the root mean square of the amplitude. Specific indexes and ratios were also computed. Data analyzed in MIP and CR were compared by paired student's t-tests., Results: MVC levels were not negatively affected by a VDO increase in CR position. On the contrary masseter muscles showed a statistically significant increase (p < 0.005). No significant effect on the anterior temporalis was observed., Conclusion: These results suggest that no immediate negative effect on maximum voluntary clenching was induced by a VDO increase in CR position. A slight increase observed in EMG clenching levels could be explained by the increase in VDO when clenching on the splint., Clinical Implications: The results of this study support the use of CR position as a pragmatic reference position due to the absence of relevant or negative changes in neuromuscular function., (© 2023 Wiley Periodicals LLC.)

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.)

Recently, many patients undergo anterior prosthetic treatment for esthetic reasons. In some patients complain about functional reasons such as inaccurate pronunciation and occlusal discomfort after the treatment. Anterior teeth are important esthetically but in the occlusal point of view, anterior guidance is the second most important factor in occlusion, next to centric relation. Failure to determine an appropriate anterior guidance might lead to posterior occlusal interference, which can highly affect the stability of the posterior teeth. Also, discomfort might occur if the customized interior guidance is not in harmony with the patient's envelope of function. The patient in this case complained of overall discomfort in the maxillary anterior area after prosthetic treatment. The expressed difficulty in pronunciation, unstable occlusion due to lack of stable holding contact and discomfort of the facial muscles. Maxillary anterior prostheses were refabricated through systematic diagnosis and treatment and thus, this case presents esthetical and functional satisfaction to both the patient and the dentist. [ABSTRACT FROM AUTHOR]

Aim: The aim and objectives of this study were to assess and compare the efficacy of a new copyrighted technique (wax ball technique, L-77997/2018) and design (denture base design for the wax ball technique, L-78006/2018) for recording centric relation (CR). Settings and Designs: In vivo - comparative study. Materials and Methods: This study was conducted on sixty consented edentulous patients. The study participants were divided into Group I and Group II. CR in Group I patients was recorded using Dawson's bimanual technique (technique 1). For participants in Group II, CR was recorded using the authors' copyrighted technique (technique 2). Time taken and accuracy of CR records by both the techniques were evaluated. Statistical Analysis Used: Descriptive statistics such as frequency and percentage were calculated for categorical variables, mean and standard deviation were calculated for quantitative variables. Independent t-test was used to compare the time taken to record the CR between the two groups. The accuracy of both the techniques was assessed by Mann-Whitney U-test. Results: The mean time taken for technique 1 was 56.47 s, whereas for technique 2, it was 5.97 s, with an overall mean difference of 50.5 s between the two techniques. Both techniques were found to be accurate, as the CR recorded during jaw relation matched with CR during trial in all the cases in both the groups (frequency 30 (N) and cumulative percentage 100%). Conclusion: From the study, it was found that, time taken for technique 2 was statistically less compared to that of technique 1, and both the techniques were found to be equally accurate. [ABSTRACT FROM AUTHOR]

Aim: The purpose of the study is to evaluate and compare the horizontal mandibular positions recorded between intraoral conventional tracer and intraoral digital tracer in upright and supine position. Materials and Methods: Twenty-four edentulous patients with well-formed ridge and adequate interarch distance space were selected. MATLAB software was assimilated with intraoral digital tracer and was utilized in the study for recording the horizontal movements of the mandible, i.e., gothic arch tracing by intraoral digital tracer and was observed on a laptop with the help of MATLAB Software. For each subject, multiple mandibular readings were recorded and analyzed through software, and similar readings were recorded with conventional intraoral tracers. The comparison between intraoral conventional tracer and intraoral digital tracer was done to assess the reliability. Moreover, the consistency of recording horizontal mandibular position was also compared between upright and supine position. Results: The data were procured and utilized in comparison for different positions revealed statistically significant difference by using Student's Paired t-test. The test resulted in supine position better compared to upright position (P = 0.0001). The association between supine position with upright position was calculated using Fischer's exact test, and it was also found to be statistically significant (P = 0.002). The Pearson's Correlation analysis was performed to check the agreement between upright and supine position and very weak downhill correlation (r²= -0.130) was observed between the two variables. Conclusion: On evaluation and comparison of horizontal mandibular position, it was found that the intraoral digital tracing technique is more valid compared to conventional intraoral tracer technique. It was also observed that the consistency of reproducibility in recording horizontal mandibular position in supine position is significantly higher than upright position. [ABSTRACT FROM AUTHOR]

To present a case report of an orthodontic treatment of a high-angle, dual bite, Class II malocclusion without extractions and with the use of mini-plates. Class II malocclusion treatment protocols vary according to the morphological component of the malocclusion and the magnitude and direction of craniofacial growth. It is generally agreed that the cooperation of the patient and careful planning of anchorage are the key determinants of successful treatment. Protrusion of the upper and lower lip and a retrognathic mandible were the patient's chief concerns. The patient had learned to project her mandible forward to disguise the overjet. The patient's parents elected to correct the malocclusion with the use of bilateral infrazygomatic mini-plates. Pre-treatment condylar stabilization with an orthotic established a stable centric relation position, followed by mounting of the models on a semi-adjustable Panadent articulator. This allowed diagnosis and treatment planning from a stable condylar position and eliminated possible misdiagnosis due to the dual bite. Distal retraction and vertical control of the upper teeth enabled correction of the Class II malocclusion with minimal patient cooperation. Mini-plate-assisted treatment corrected the excessive overbite and overjet. The patient completed treatment with a stable occlusion and no longer postured her jaw forward. The parents and patient were completely satisfied with the positive treatment outcome. A 2-year follow-up confirmed the clinical stability. [ABSTRACT FROM AUTHOR]

Copyright of RSBO: Revista Sul-Brasileira de Odontologia is the property of UNIVILLE 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.)

To present a case report of an orthodontic treatment of a high-angle, dual bite, Class II malocclusion without extractions and with the use of mini-plates. Class II malocclusion treatment protocols vary according to the morphological component of the malocclusion and the magnitude and direction of craniofacial growth. It is generally agreed that the cooperation of the patient and careful planning of anchorage are the key determinants of successful treatment. Protrusion of the upper and lower lip and a retrognathic mandible were the patient's chief concerns. The patient had learned to project her mandible forward to disguise the overjet. The patient's parents elected to correct the malocclusion with the use of bilateral infrazygomatic mini-plates. Pre-treatment condylar stabilization with an orthotic established a stable centric relation position, followed by mounting of the models on a semi-adjustable Panadent articulator. This allowed diagnosis and treatment planning from a stable condylar position and eliminated possible misdiagnosis due to the dual bite. Distal retraction and vertical control of the upper teeth enabled correction of the Class II malocclusion with minimal patient cooperation. Mini-plate-assisted treatment corrected the excessive overbite and overjet. The patient completed treatment with a stable occlusion and no longer postured her jaw forward. The parents and patient were completely satisfied with the positive treatment outcome. A 2-year follow-up confirmed the clinical stability. [ABSTRACT FROM AUTHOR]

There are very little controversies on occlusion in healthy individuals, where centric relation is regarded as the criterion for assessing the present occlusion and also for establishing a new occlusal relationship between the upper and the lower jaws. On the other hand, the occlusal position in patients with deformed condyles still remains to be clarified. In this review, the effectiveness and limits of centric relation in these patients are discussed. In addition, the muscle induced occlusal positions, such as the muscular position and the terminal positions of habitual closing movements, are suggested as a substitution for centric relation. Finally, the importance of a stable intercuspal position, where the habitual closing movements terminate without any premature tooth contact, is emphasized.

Introduction and aims: Exact registration of the centric relation by the edentulous patient is one of the main pillars of dentures stability and retention. This registration is possible using the conventional method with the occlusal rims according to Walkhof, or modification of it, or instrumental method - a gothic arch tracing. The aim of this paper is to compare conventional with the instrumental method and statistical accuracy of them. Methods: It was set the file of 267 patients with upper or lower complete denture. The patients were examined clinically and the panoramatic X-ray (orthopantomogram) was done. By 201 patients (75.3%) from our file was indicated upper and lower complete denture, both jaws were edentulous. Patients from our file were divided into two groups. The first group includes the patients where the registration was done using the conventional method, and the second group of patients where the registration was done by using the gothic arch method and Gerber's facebow registration. Results: The results of the examination were evaluated statistically and it was shown that registration of centric relation is more accurate using the gothic arch method. Conclusion: From our investigation it is apparent that during the procedure of upper and lower complete denture is recommended to set the centric relation registration using instrumental methods.

Background/Aim. Postoperative condylar position is a substantial concern in surgical correction of mandibular prognathism. Orthognathic surgery may change condylar position and this is considered a contributing factor for early skeletal relapse and the induction of temporomandibular disorders. The purpose of this study was to evaluate changes in condylar position, and to correlate angular skeletal measurements following bimaxillary surgery. Methods. On profile teleradiographs of 21 patients with mandibular angular and linear parametres, the changes in condylar position, were measured during preoperative orthodontic treatment and 6 months after the surgical treatment. Results. A statistically significant difference in values between the groups was found. The most distal point on the head of condyle point (DI) moved backward for 1.38 mm (p = 0.02), and the point of center of collum mandibulae point (DC) moved backward for 1.52 mm (p = 0.007). The amount of upward movement of the point DI was 1.62 mm (p = 0.04). Conclusion. In the patients with mandibular prognathism, the condyles tend to migrate upward and forward six months after bimaxillary surgery.

Purpose. The purpose of the study was to determine whether the hinge axis registration and the transfer modality (facebow transfer vs. average mounting) from the subject to the articulator affect the three-dimensional condylar shift between the centric relation (CR) and the maximum intercuspation (MI) position. Material and Methods. The study was comprised of 32 fully dentate subjects (16 male and 16 female). Only the asymptomatic participants with normal occlusal relations (Angle class I) aged 20 - 33 (mean age 22.6 ± 4.7) met the inclusion criteria. Three-dimensional condylar shift (anteroposterior, superoinferior and mediolateral shift) between the centric relation position (CR) and the maximum intercuspation (MI) position was analyzed by means of Mandibular Position Indicator (SAM Prazisionstechnik GmbH, Muenchen, Germany). Results. The average three-dimensional condylar shift was 0.13 ± 0.12 mm for facebow transfer and 0.22 ± 0.23 mm for average mounting. There were no statistically significant differences noted between genders. The results of the Mann-Whitney test showed statistically significant differences for anteroposterior and superoinferior condylar shift (P < 0.001). However, the difference in the mediolateral shift was not statistically significant. Conclusions. In order to find discrepancies within the three-dimensional condylar shift, facebow transfer proved to be more accurate than the average mounting in the semi-adjustable articulator. However, the average value of three-dimensional shifts of the condyle did not differ from normal values and they did not have clinical significance. Thus, both ways of transfer modalities (facebow transfer and average mounting) in asymptomatic subjects with normal occlusion can be considered reliable.

Temporomandibular joint (TMJ) forms an integral functional part of stomatognathic system. Position, shape, structure and function of teeth have an influence on the proper functioning and health of TMJ. But a problem associated with TMJ is often neglected, and treatment for it is mostly restricted to palliative therapy. A proper understanding of the underlying cause of temporomandibular joint disorder (TMD) is necessary to device a proper treatment plan. Etiology of TMDs varies from idiopathic reasons to systemic disorders. The option of Gnathological splint is a conservative, safe and an effective mode of therapy for TMDs caused by occlusal discrepancies (fulcrum/interferences). This article presents a case report of a patient with TMD caused by occlusal discrepancy

Patients with a complex problem set involving multiple levels of altered structure challenge the clinician to develop an individualized, appropriate treatment plan. Dentofacial deficiency, occlusal problems, and loss of tooth structure require intervention to establish stability and regain function, speech, esthetics, and masticatory muscle comfort. The comprehensive examination must quantify each problem to specify the diagnosis for realistic treatment planning. The clinical case of a patient with Costello syndrome is presented to illustrate essential concepts in diagnosis and treatment of complex cases, including (1) Global Diagnosis of anterior esthetic relationships, (2) occlusal analysis with diagnostic casts verified in centric relation, (3) comprehensive restoration previewed with a diagnostic wax-up and removable acrylic resin overlay, (4) adhesive monobody composite resin onlays that preserve tooth structure, and (5) programmed occlusion, quantified with digital occlusal analysis, to ensure stability and comfort. Costello syndrome is a neurodevelopmental syndrome causing multisystem effects, including a distinctive craniofacial phenotype, cardiovascular disease, intellectual disability, growth hormone deficiency, and dental abnormalities such as delayed dental development, bruxism, and demineralized enamel lesions. In the present case, quantification of the patient's problem set allowed precise treatment planning that resulted in predictable restoration., Competing Interests: No conflicts of interest reported.

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