Journal of Craniomandibular Function, 01/2020

Purpose: This retrospective cohort study in an asymptomatic nonpatient population evaluated the prevalence of specific morphologic changes usually associated with the presence of degenerative joint diseases (DJDs) using cone beam computed tomography (CBCT) and examined the associations between DJD and age, sex, and number of teeth present. Materials and methods: CBCT images (268 temporomandibular joints [TMJs]) of 134 asymptomatic patients were studied. Patient data were obtained from clinical records, and calibrated examiners interpreted the CBCT images. The presence or absence of traditional radiographic signs of DJD (erosion, generalized sclerosis, osteophytes, and subchondral cysts) in the condyle and articular eminence of each TMJ were evaluated. The data were submitted to bivariate (chisquare and Fisher exact tests) and multivariate (Poisson regression) analyses (α = 0.05). Results: The sample was primarily composed of males (52.24%) and individuals aged ≥ 61 years (55.64%); 61.94% were partially edentulous with ≤ 12 teeth in the oral cavity. The most common DJD diagnoses were mandibular condyle osteophytes (30.22%) and erosion (12.69%), followed by articular eminence erosion (8.58%) and mandibular condyle subchondral cysts (7.09%). The bivariate analysis showed a statistically significant association between females and subchondral cysts (P = 0.007), between edentulous individuals and subchondral cysts (P = 0.008), and between individuals with ≤ 12 teeth and mandibular condyle erosion (P = 0.005). In the adjusted Poisson regression analysis, a significant association was found between DJD and sex (P = 0.015). Conclusion: Despite the limitations of this study, the results show a high prevalence of morphologic changes usually associated with the presence of DJD in asymptomatic subjects. Osseous TMJ abnormalities were present mostly in females, individuals with a lower number of teeth, and older individuals. (Originally published in Int J Prosthodont 2018; 31:4:321–326.)

Minimally invasive procedures such as arthroscopy and arthrocentesis are therapeutic options for internal derangement (ID) of the temporomandibular joint (TMJ). This article describes the results of a pilot study of a digital surgical template designed to facilitate these procedures. Materials and methods: Divisible, patient-specific digital templates were designed using cone beam computed tomography (CBCT) and optical facial scan data, then 3D printed and tested in a first clinical trial on three patients who underwent template-guided minimally invasive temporomandibular joint surgery (MITMJS) consisting of arthroscopy (three TMJs) or arthrocentesis (three TMJs). Results: The template design and clinical use proceeded as planned. All templates showed excellent fit and provided direct access to the upper joint space. No complications were observed for any of the surgeries. Conclusions: Template guidance can facilitate MITMJS. Divisibility is an important design feature, making it possible to remove or reposition the template during surgery, if necessary. The proposed inhouse workflow results in low-cost production. Keywords: surgical template, computer-assisted surgery, minimally invasive temporomandibular joint surgery

The first article in this series described the development of a new method of dental functional analysis called the PlaneSystem (Zirkonzahn, Gais, Italy), which enables the exact transfer of clinical parameters from the patient's mouth to the articulator. Among the issues discussed was the context of the need out of which this system emerged. Background knowledge of the stages of research and development promotes a deeper understanding of the topic at hand, a major focus of which is the tapping into a wealth of patient-specific data collected by the analog route (including information on head posture; facial proportions; the physiognomic map; analysis of the study model; orientation of the study model; jaw movement recording; joint mechanics; and the non-manipulated, physiologic position of the mandible in centric relation). The new system registers the individual patient's occlusal plane and asymmetries as well as the vertical dimension of occlusion (VDO) and mandibular alignment, and accurately transfers this positional information to the articulator. This article, the second in the series, focuses on the digital processes involved in this process. All physically collected patient data can be integrated into the digital workflow and referenced to purely virtual solutions. Mandibular movements can be recorded and transferred to a physical or virtual articulator using the JMAnalyser+ (Zebris Medical GmbH, Isny, Germany) interface integrated into the PlaneSystem. This allows for the reconstruction of dynamic contact relationships relative to the referenced position of the maxilla. Keywords: occlusal plane, articulator, mandibular position, maxillary position, PlaneFinder, centric, functional analysis, bite registration, vertical dimension of occlusion (VDO), dental technology-related analysis

Dental functional analysis and treatment specialists have also been impacted by a growing number of disputes over the legal basis for billing various examination and treatment services in recent years. This problem is rooted in the fact that the German Dental Fee Schedule (GOZ), which was reformed by the Federal Government in 2012, is generally binding, so dentists are legally obligated to abide by its provisions without exception (Article §1 GOZ) unless otherwise provided by law. As craniomandibular function and disorders-related services do not fall under the contract dental services provided for under Article §28 (2) 8 of German Social Code V, this impacts all patients in need of functional analysis and treatment. In and of itself, this regulation is clear. Nevertheless, the billing of functional analysis and treatment services is problematic because the fee schedule contains a table of fees for a list of services that is incomplete, especially in this area. This peculiarity is formally recognizable by the fact that Article §6 (1) of the GOZ contains a provision that expressly allows dentists to set fees for independent services not included in the Dental Fee Schedule commensurate with the fees charged for similar analogous services included in the fee schedule ('analogous billing' procedure). The legislators inserted this provision to circumvent the need for periodic short-term updates to the fee schedule; at the same time, the analogous billing procedure allows dentists to meet their obligation to provide treatment consistent with the standards of the current state of science, as specified in the Dentistry Act. The 'List of Analogous Dental Services' published by the German Dental Association serves as a reference for dentists who provide independent services not included in the GOZ fee schedule and thus do their invoicing based on the analogous billing procedure. The list is updated semiannually but is presented without commentary or explanations of the contents. The Commentary to BEMA & GOZ1, a detailed independent fee schedule commentary introduced decades ago and recognized by the German Dental Chambers and courts, is one publication that takes on this task. The present article, written by one of its co-authors, describes the extent to which condylar position analysis is an independent dental service, and the billing procedure for this service. Keywords: craniomandibular dysfunction (CMD), instrumental functional analysis, condylar position analysis, German Dental Fee Schedule, GOZ, fee schedule, analogous billing

Craniomandibular function is an interdisciplinary area of study designed to provide students with a good knowledge of complex physiological, pathophysiological, and medical principles as well as knowledge and proficiency in the use of articulators and in the simulation of mandibular movements. Due to changes to Germany's Dental Licensure Act (AOZ), preclinical dental technology-related course contents will be cut back in the near future. The German Society of Craniomandibular Function and Disorders (DGFDT) therefore launched a consensus-building process in collaboration with representatives of the prosthodontic faculties of German universities with the aim of elaborating a list of essential Craniomandibular Function-Based Learning Objectives (CFLO) and competence levels for preclinical and clinical dental education. The National Competence-Based Learning Objectives for Dental Education (NCLO) should be revised to include the consensus-based CFLO. Keywords: learning objectives, craniomandibular function and therapy, occlusion, dental education