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

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

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

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

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

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

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

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

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

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

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

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

Aim: The Aim of the study was to evaluate the reproducibility of condylar inclination values obtained using three different interocclusal recording materials in Hanau Wide-Vue semi-adjustable articulator and tocompare those values of condylar inclination with panoramic radiographic images. Settings and Design: In Vivo Comparative study. Materials and Methods: The clinical trial was carried out in the Department of Prosthodontics, M. R Ambedkar Dental College and Hospital, Bengaluru. A total of 30 dentulous subjects aged between 20 and 40 years were selected, without any signs and symptoms of temporomandibular joint disorders. With the help of a custom-made protrusive guide, protrusive records for three materials were made. These records were used for programming the articulator and the respective horizontal condylar inclination (HCI) value, and panoramic radiographs were made. The values obtained were statistically analyzed. Statistical Analysis Used: Independent t-test, multiple comparisons using Bonferroni method followed by Analysis of variances (ANOVA) were used. Results: Among each pair of groups there exists a significant difference, i.e., the mean condylar inclination (degree) was found to be statistically significant between wax and polyvinyl siloxane (P < 0.01) as well as between wax and polyether (P < 0.01). No significant difference was observed between polyvinyl siloxane and polyether (P > 0.05). Conclusion: HCI values differed depending on the type of material employed. The study concluded that the protrusive condylar guidance angles obtained by panoramic radiograph can be used in programming the semi-adjustable articulator and among the materials polyether gave the highest Condylar Guidance values with less variability and wax gave lowest values with greater variation. [ABSTRACT FROM AUTHOR]

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

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

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

Objectives: Programming of joint mechanism/parameters (sagittal condylar inclination and Bennett angle) of adjustable dental articulators is a prerequisite for performing positions and movements of the mandible. The aim of the study was to test significant differences between the two methods (wax eccentric records and Arcus Digma device) of measuring these joint parameters by using three different dental articulators (SAM 3, Protar 7; and Artex CR). Materials and Methods: Thirty asymptomatic younger (age 25.7 ± 2.9 years) subjects (dental medicine students) divided by gender, with normal occlusion (Angle class I) participated in the study. After taking anatomical impressions of both dental arches, master casts were made of hard dental plaster for each subject. The values of the left and right sagittal condylar inclination and Bennett angle by the two methods of wax eccentric protrusive and lateral records and Arcus Digma device were measured for the purpose of programming the mentioned joint parameters in three different articulator systems. Results: The average values of the measured parameters of sagittal condylar inclination and Bennett angle of wax eccentric records were higher (ranging from 5ºto 10º) in relation to the values measured by Arcus Digma device. Statistically significant differences found between the measured joint parameters (p

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

In fabricating a prosthetic rehabilitation, whether it consists of just a single crown or a complete-mouth reconstruction, one of the main aims of the clinician is to simplify the procedures and reduce the time necessary to integrate it into the mouth of the patient. This article completes the description of the rationale behind the selection of semi adjustable articulators and of a way to transfer to the laboratory technician valuable information that, in the case of extensive rehabilitations, will make occlusal optimization more error free. [ABSTRACT FROM AUTHOR]

The development of an occlusal scheme with an appropriate number and location of occlusal contacts is of the utmost importance for the long-term success of any prosthetic rehabilitation. This, however, can be a time-consuming procedure. To avoid undue mistakes, a high degree of competence must be demonstrated by both the clinician and the technician. Especially when performing extensive rehabilitations, many operators believe that to have optimum control of the occlusal variables, it is necessary to employ rather sophisticated instruments and complicated procedures. This article presents a rationale for an approach that uses a simplified but sound instrumentation in the clinical and laboratory steps necessary to produce a successful prosthesis. In part 1, the registration of the spatial position of a patient's maxillary and mandibular arches is described. [ABSTRACT FROM AUTHOR]

Aim: To demonstrate and evaluate molar distalization treatment with an intra-arch device provided with the Onplant system for absolute anchorage. Methods: Absolute anchorage was achieved using an Onplant placed subperiosteally in the palate to create osseointegration. The Onplant was, via an abutment, connected to a transpalatal bar that was bonded to the anchorage teeth. Two sectional arches were attached bilaterally to brackets and tubes on premolars and molars in the maxilla. A compressed open nickel titanium coil was inserted between the second premolar and the first molar to create molar distalization. The method is described and illustrated with a case report showing the nonextraction treatment of a patient with a Class II malocclusion and space deficiency in the maxilla. Results and Conclusion: It was demonstrated that an intra-arch device provided with an Onplant system for absolute anchorage is suitable for maxillary molar distalization. The Class II molar relationship was transformed to a Class I relationship during 4.5 months of treatment, and the amount of simultaneous distal movement of maxillary first and second molars was 2.5 mm. No anchorage loss could be found, ie, there was no forward movement of the anterior teeth. The patient had no problems with the surgical placement of the Onplant system. [ABSTRACT FROM AUTHOR]

Purpose: This article describes a new procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus. Materials and Methods: Preoperatively, the framework was fabricated on a photocurable resin skull model produced from a CT scan and individually designed guide template. The implants were immediately placed using the guide template; laser welding connected the components of framework. Results: Despite the custom-made prosthesis, the total treatment from implant placement to superstructure placement can be completed within only 1 day. Conclusion: This procedure for immediate implant-supported oral rehabilitation using a photocurable resin skull model and a laser-welding apparatus may be useful for any implant system and patient. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to develop an easy-to-use procedure for individual registration and to test its accuracy. Unlike common principles, the method should be based on a transfer of the articulator geometry to the patient. Materials and Methods: The system consists of an articulator holding a bite plate in a standard position. The bite plate connects to an electronic recording system, which transfers the articulator's condylar points virtually to the patient's mandible by a centric relation record. The trajectories of the transferred points are recorded during mandibular protrusions and laterotrusions. From the trajectories, sagittal condylar and Bennett angles are measured and are adjusted at the articulator after mounting of the casts via the bite plate. Using a mechanical testing device, the accuracy of the measured angles was examined by comparison with preset values varying from 10 to 60 degrees (condylar angle) and from 0 to 40 degrees (Bennett angle) in 10-degree increments. Results: The mean deviations of measured condylar angles from preset values ranged between 1.5 and 0 degrees. The mean deviations of the Bennett angles ranged from -0.5 to -1.3 degrees. Conclusion: The transfer of articulator geometry to the patient reduces the number of individual parameters necessary to imitate jaw motion to the condylar and Bennett angles. This leads to a significant simplification in registration and cast transfer. Since the required parameters are recorded with high accuracy, the method could be an alternative to traditional sophisticated instrumental registration. [ABSTRACT FROM AUTHOR]

It has been proposed that the discrepancy between the seated and unseated condylar position be identified and eliminated when the occlusion is reorganized. Identification of this discrepancy is most accurately accomplished through the use of diagnostic casts that have been taken from a deprogrammed patient and mounted in the seated condylar position on a semiadjustable articulator through an estimated facebow transfer. The amount and direction of any discrepancy is determined three dimensionally with condylar position instrumentation. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate whether the interchangeability of new Hanau semiadjustable articulators fulfills the manufacturer's criterion (102 µm) in the mediolateral direction and the defined 166-µm criterion three dimensionally and whether the articulators maintain the same interchangeability as new articulators after a period of function. Materials and Methods: The spatial deviations in three dimensions of ten new, ten 18-month-old, and ten 30-month-old Hanau articulators were measured with a field inspection gauge and compared to those of a master articulator. Results: Compared to the master articulator, nine of 10 new articulators met the manufacturer's criterion of articulator interchangeability in the mediolateral direction. However, only four of the 10 articulators fulfilled the criterion for three-dimensional interchangeability. The articulators were found to be interchangeable among the groups when the spatial deviations of test articulators from the master articulator at the position of the lingual cusp of the right maxillary first premolar were compared. However, using the geometric mean deviations of test articulators, the 30- month group was not interchangeable with the new and the 18-month articulator groups. Conclusion: This limited study revealed that most of the articulators tested met the manufacturer's criterion of articulator interchangeability, but most did not pass the three dimensional interchangeability test. Clinicians should be aware of the amount of occlusal error in the range of 0.2 mm that may result from interchanging dental casts on the articulator system. The articulator system might be able to maintain the same level of interchangeability for up to 18 months of routine use. [ABSTRACT FROM AUTHOR]

Purpose: Interchangeability between articulators allows mounted casts to be transferred accurately from one articulator to another. The purpose of this study was to evaluate the interchangeability of 109 new, unused interchangeable articulators in the centric position. Materials and Methods: The interchangeability of 38 unused Whip Mix model #2240 and 71 unused model #3040 semiadjustable articulators was evaluated using the Whip Mix #2245 check system as the standard. Vertical discrepancies between the check system cylinders were also measured. Results: Within the standard for interchangeability established by the Whip Mix #2245 check system (< 94 µm horizontal discrepancy), 101 (93%) of 109 articulators were interchangeable (34 were model #2240 and 67 were model #3040). Overall, the amount of vertical space between the check system cylinders was ≤ 52 µm in 99.4% of the model #2240 articulators and 99.7% of the #3040 articulators. Conclusion: New, unused Whip Mix model #2240 and #3040 articulators are potentially interchangeable in the centric position. [ABSTRACT FROM AUTHOR]

Numerous authors and textbooks have advocated the concept of bilateral simultaneous occlusal contacts as one of the necessary components of an optimum occlusal condition. All occluding surfaces should meet at the same moment of time during a mandibular closure. Articulating paper labeling that appeared widely distributed throughout the arch was thought to represent this advocated occlusal condition. However, computerized occlusal analysis shows that true bilateral occlusal contact time simultaneity is not accurately represented by widespread paper labeling. Articulating paper labeling is an inadequate indicator of perceived occlusal contact time simultaneity as it renders no occlusal contact force or time sequencing. When occlusal adjustments are guided by computerized occlusal analysis, occlusal contacts on all potentially occluding teeth can be approximated to occur within .2 second. This technique report describes a clinical procedure that employs computerized occlusal analysis to guide sequential occusal adjustments to obtain measurable bilateral occlusal contact simultaneity. Additionally, the phenomenon of how articulator paper labeling can be a misleading indicator of occlusal contact timing and force content is presented. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the effect of experimental alterations of nonworking-side occlusal contacts on jaw-elevator muscle activity. Materials and Methods: Individual devices were fabricated to simulate various lateral occlusal relationships. Twelve human subjects were asked to carry out submaximal lateral clenching, and electromyographic (EMG) activity of the masseter and anterior and posterior temporalis muscles was measured. Results: Clenching in a lateral mandibular position under natural conditions induced an activity pattern with a clear dominance of the anterior and posterior temporalis muscles on the working side. Working-side dominance in the anterior temporalis was reduced moderately when an experimental nonworking-side occlusal contact was added. Dominance decreased dramatically when an experimental nonworking-side interference was added. The working-side activity in the posterior temporalis was also reduced dramatically by an experimental nonworking-side interference, but not by a nonworking-side occlusal contact. None of the experimental contact patterns had a significant effect on the masseter activity. Conclusion: These results suggest that the nonworking-side occlusal contacts have a significant effect on clenching-induced temporalis muscle activity. [ABSTRACT FROM AUTHOR]

Purpose: Although dental composites are excellent for restoring the appearance of natural tooth tissues, their relatively poor resistance to wear, especially in approximal and occlusal contact areas, is still a major source of concern. The aim of this research was to study a basic wear mechanism, under 2-body wear conditions, that may be integrated into our understanding of the in vitro and in vivo wear behavior of dental composites. Materials and Methods: An in vitro 2-body wear test was conducted on 2 selected ultrafine compact-filled dental composites under different magnitudes of sinusoidal cyclic load. The wear surfaces and cross sections of the wear layers were assessed using scanning electron microscopy (SEM) to explore the nature of the wear pattern of the dental composites under cyclic loading conditions. Results: The wear losses of both composites increased with load. SEM analysis of wear surfaces and subsurface sections indicated that the composites tested displayed different wear mechanisms from low to high loads. An explanation for the wear pattern is proposed based on the observed wear behavior. Conclusion: The in vitro wear pattern of the ultrafine compact-filled dental composites tested is closely related to the applied load. Although the wear loss increased in a roughly linear relationship with applied load, the underlying wear mechanism involved may experience a significant change from low to high load conditions during wear. [ABSTRACT FROM AUTHOR]

Purpose: Functional relationships between occlusal errors and articulator settings have been the subject of numerous investigations. It is, however, not known how frequently errors of a certain size occur under practical conditions. This study attempted to estimate the frequency of occlusal errors that can be expected with the different levels of registration and articulator adjustment that are currently used. Materials and Methods: In 57 asymptomatic subjects, individual articulation parameters, including the condylar and Bennett angles, the spatial relation of dental arches, and the intercondylar distance, were determined experimentally. Tooth-guided lateral movements of the subjects' casts were simulated in a virtual articulator that was programmed to the individual parameters of each person. With respect to this reference setting, occlusal errors that would emerge with different modes of semiindividual adjustment were calculated. The intercondylar distance thereby remained fixed at 110 mm. Results: With complete mean value setting, occlusal errors would exceed 200 µm at the second molar in 16% of the subjects and 300 µm in 6% of the subjects. Individual facebow registration of condylar angles and spatial relations would reduce these rates to 13% (200 µm) and 3% (300 µm). With additional setting of Bennett angles, occlusal errors would exceed the mentioned limits in no more than 1.6% and 0.1% of cases, respectively. This extensive mode of adjustment became, however, increasingly ineffective with higher demands for occlusal accuracy. Conclusion: Complete mean value setting is associated with a relatively low risk of occlusal errors exceeding tolerance limits that are widely accepted in practice. Compared to mean value setting, facebow registration of condylar angle and relations yields no profitable improvement of occlusal accuracy. [ABSTRACT FROM AUTHOR]

The objective of this preliminary study was to determine if the occlusal contact surface registered with an articulating paper during fixed prosthodontic treatment was contained within the area marked on a thicker articulating paper. This information would optimize any necessary occlusal adjustment of a prosthesis' veneering material. A convenience sample of 15 patients who were being treated with an implant-supported fixed single-unit dental prosthesis was selected. Occlusal registrations were obtained from each patient using 12-µm, 40-µm, 80-µm, and 200-µm articulating paper. Photographs of the occlusal registrations were obtained, and pixel measurements of the surfaces were taken and overlapped for comparison. The results showed that the thicker the articulating paper, the larger the occlusal contact area obtained. The differences were statistically significant. In all cases, the occlusal registrations obtained with the thinnest articulating paper were contained within the area marked on the thickest articulating paper. The results suggested that the use of thin articulating papers (12-µm or 40-µm) can avoid unnecessary grinding of veneering material or teeth during occlusal adjustment. [ABSTRACT FROM AUTHOR]

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Occlusal splints are commonly used to position the maxilla during traditional orthognathic surgery. We aimed to quantify the inaccuracy of the maxillary positioning (in three dimensions) in traditional model surgery with the Orthopilot® navigation system. Thirty Le Fort I osteotomies were made using a standard technique. The position of the maxilla was recorded by the navigation system and defined by three values of translation and three of rotation. The recorded data were compared with the planned data. The accuracy of positioning was classified in distinct classes with three major criteria (conformity, non-conformity, and failure) according to the discrepancy. The positioning of the maxilla was in conformity with operative planning in 3/30 of our Le Fort I osteotomies (95% CI 2% to 27%) and in failure in 22/30 (95% CI 54% to 88%). The dispersion of the discrepancy was more important in the sagittal plane, particularly for the sagittal rotation and for the back-front translation, which reflected greater inaccuracy in this plan. The frontal orientation of the maxilla was better controlled. The risk of maxillary malposition was proportional to the planned maxillary advancement. [ABSTRACT FROM AUTHOR]

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