Reliability of landmark identification for analysis of the temporomandibular joint in real-time MRI.

BACKGROUND: Real-time magnetic resonance imaging (rtMRI) is essential for diagnosing and comprehending temporomandibular joint (TMJ) movements. Current methods for tracking and analysis require manual landmark placement on each acquisition frame. Therefore, our study aimed to assess the inter- and intra-rater reliability of placing cephalometric landmarks in frames from a dynamic real-time TMJ MRI. MATERIAL AND METHODS: Four real-time MRIs of the right TMJ were taken during mandibular movement at ten frames per second. Seven dentists identified ten landmarks on two frames (intercuspal position-ICP-and maximum mouth opening-MMO) twice at a two-week interval, yielding 112 tracings. Six typical cephalometric measurements (angles and distances) were derived from these landmarks. The reliabilities of landmarks and measurements were evaluated using distance-based (dbICC), linear mixed effect model intraclass correlation (lmeICC), and standard ICC. RESULTS: The average inter-rater reliability for the landmarks stood at 0.92 (dbICC) and 0.93 (lmeICC). The intra-rater reliability scores were 0.97 and 0.98. Over 80% of the landmarks showed an ICC greater than 0.98 (inter-rater) and over 0.99 (intra-rater). The lowest landmark ICC was observed for the orbitale and the oblique ridge of the mandibular ramus. However, the cephalometric angle and distance measurements derived from these landmarks showed only moderate to good reliability, whereas the reliability in the frames with ICP was better than those with MMO. Measurements performed in the ICP frame were more reliable than measurements in the MMO frame. CONCLUSION: While dentists reliably localize isolated landmarks in real-time MRIs, the cephalometric measurements derived from them remain inconsistent. The better results in ICP than MMO are probably due to a more familiar jaw position. The higher error rate of the TMJ measurements in MMO could be associated with a lack of training in real-time MRI analysis in dentistry.

Radiodiagnostics of standard orthodontic radiographs-dental and extradental incidental findings : Do we see everything we should see?

OBJECTIVES: The extent of undetected incidental findings in routine orthodontic radiographs is still unknown. However, incidental findings that are not in the primary focus of orthodontic diagnostics may be of high medical relevance. Therefore, this study aimed to analyse whether incidental findings are reliably detected and which parameters influence the orthodontist's assessment. METHODS: In a clinical cross-sectional study 134 orthodontists evaluated two orthopantomogram (OPT) and two lateral cephalogram (LC) radiographs each via a standardised online survey. The radiographs were previously examined by three dentists and one radiologist-in a pilot phase-regarding the number of incidental findings and subsequently defining as gold standard in a consensus procedure. The radiographs were presented consecutively, the number of incidental findings detected were noted and the individual findings could be described in free text form. RESULTS: Overall, 39.1% of the incidental findings were detected. The orthodontists' focus was primarily on the dental region. Here, 57.9% of incidental findings were detected, while 20.3% were detected in extradental regions (p < 0.001). A highly relevant finding of suspected arteriosclerotic plaque was detected in 7.5% of cases (OPT). Significantly more incidental findings were detected on OPTs than on LCs (OPT 42.1%, LC 36.0%, p < 0.001). As participants' length of professional experience increased, significantly more time was spent on the assessment (p < 0.001), correlating positively with the detection of incidental findings. CONCLUSIONS: Even in daily routine practice, attention must be paid to a thorough assessment of all radiographed regions. The factors time and professional experience can prevent practitioners from overlooking findings outside the orthodontic focus.

Evaluation of occlusal function during orthognathic therapy : A prospective clinical trial using a digital registration method.

OBJECTIVES: Reduced occlusal function is a main characteristic of orthognathic patients. The present study aimed to investigate the extent of therapy-induced functional improvements in occlusal function using a digital diagnostic method. METHODS: This prospective clinical study included 41 orthognathic patients (24 women and 17 men, median age 27.26 ± 8.2 years) and 10 control patients (5 women and 5 men, median age 29.8 ± 13.5 years) with neutral skeletal and dental configurations. The patients were divided into classes I, II and III based on their cephalometry. Digital occlusal registrations in habitual occlusion in an upright sitting position were taken before (T1) and after (T2) therapy using the T­Scan Novus (Tekscan, South Boston, MA, USA) application. RESULTS: Class II and III patients showed a significantly less efficient occlusal pattern than the untreated controls regarding total antagonism (p < 0.001), time of occlusion (p = 0.004), occlusal asymmetry (p = 0.001), anterior antagonism (p < 0.001) and posterior antagonism (p < 0.001). After therapy, the occlusal pattern increased in both therapy groups, where class III patients became indistinguishable from the controls, and class II patients differed only in posterior antagonism (p = 0.035). CONCLUSIONS: The digital occlusal registration method proved to be a useful diagnostic tool and provided new insights into therapeutic effects in orthognathic patients. By precisely adjusting the occlusal function, masticatory performance improved significantly. CLINICAL RELEVANCE: Severe malocclusion leads to a significantly lower masticatory performance for patients, which can be improved by orthognathic therapy and captured by digital occlusal registration.

Prevalence of incidental findings in adult vs. adolescent patients in the course of orthodontic X-ray diagnostics.

OBJECTIVE: Due to increasing numbers of adult patients presenting to orthodontic practices, an increase in incidental findings on diagnostic X­rays, which are the cornerstone of orthodontic diagnostics, is expected. This raises the clinically relevant question of whether an age effect exists regarding prevalence, localisation and severity of incidental findings on orthodontic diagnostic X­rays. MATERIALS AND METHODS: The clinical, primarily retrospective study examined pathological incidental findings from 600 orthopantomograms (OPT) and lateral cephalogram (LC) images in two groups of orthodontic patients (group I: 150 children/adolescents, age 11.89 ± 2.47 years; group II: 150 adults, age 27.03 ± 10.42 years). Prevalence, localisation and severity of the findings were recorded based on a classification sheet. The assessment was done by three experienced examiners following a systematic approach along the nine locations: mandible, maxilla, dentition, paranasal sinuses, temporomandibular joint, cranial base, orbit, cervical spine, soft tissues. RESULTS: In all, 1458 incidental findings were detected, with 66% of the findings having occurred away from the dentition. There was a significant age effect (p < 0.001) with respect to the prevalence of incidental findings (group II-adults 1026 findings-OPT: 566/LC 460 vs. group I-children/adolescents 432 findings-OPT: 221/LC 211). Regarding localisation, incidental findings in adults commonly occurred in the dentition, paranasal sinuses and mandibular regions. Furthermore, analysis of the LC images revealed significantly more incidental findings in the area of the cranial base and cervical spine in adults (p < 0.001, p = 0.003). Categorisation according to the severity of the incidental findings showed that 33% of the incidental findings needed further diagnostic investigation and possibly treatment by other specialities. CONCLUSION: Diagnostic assessment using orthodontic diagnostic X­rays results in a high prevalence of incidental findings away from the dentition. Particularly in adults, a large number of incidental findings outside the dental/alveolar region may be expected on orthodontic diagnostic X­rays. Thus, a structured approach during diagnostic assessment is required to minimise the extent to which incidental findings of clinical relevance are overlooked.

Three-dimensional mandibular characteristics in skeletal malocclusion : A cross-sectional study.

PURPOSE: We aimed to comprehensively analyse a possible correlation between skeletal malocclusions, gender and mandibular characteristics in all three dimensions in adults and to identify mandibular characteristics that are typical for extreme skeletal patterns. METHODS: A 3D model of the skull was calculated in 111 adult patients (mean age = 27.0 ± 10.2 years; 49 women, 62 men) from available computed tomography or cone beam computed tomography scans of their heads. Based on the 3D models, the skeletal patterns were examined in (a) the transversal dimension regarding asymmetry according to menton deviation, (b) the sagittal dimension according to the Wits appraisal and (c) the vertical dimension according to the maxillomandibular plane angle. The mandibular characteristics assessed were linear (ramus height and width, body length), angular (ramus, gonial and body angle) and volumetric (ramus/mandibular volume, body/mandibular volume) parameters. RESULTS: No correlation between transversal skeletal asymmetry and mandibular characteristics were found, while sagittal (F(16, 174) = 3.32, p < 0.001, η2 = 0.23) and vertical (F(16, 174) = 3.18, p < 0.001, η2 = 0.23) skeletal patterns were shown to have a significant effect on the mandible. Gender correlated with mandibular characteristics independently from the skeletal pattern. Discriminant analysis revealed that class II and III patients differed in ramus and body angle with class II patients showing higher angles (ramus angle: class II = 89.8 ± 3.9° vs. class III = 84.4 ± 4.8°; body angle: class II = 87.7 ± 4.8° vs. class III = 82.1 ± 5.2°). Hypo- and hyperdivergent patients were discriminated by gonial angle, body angle and body/mandibular volume with hyperdivergent patients having a greater gonial and body angle and body/mandibular volume (gonial angle: hypodivergent = 114 ± 9.3° vs. hyperdivergent = 126.4 ± 8.6°; body angle: hypodivergent = 82.9 ± 4.4° vs. hyperdivergent = 87.7 ± 6.5°; body/mandibular volume: hypodivergent = 72.4 ± 2.7% vs. hyperdivergent = 76.2 ± 2.6%). CONCLUSION: When analysing 3D data for treatment planning of adult patients, the orthodontist should pay attention to angular and volumetric characteristics of the mandible to identify extreme skeletal sagittal or vertical malocclusions.

Desmoid fibromatosis in the pharyngeal wall: A case report and literature review.

Desmoid fibromatosis (DF) is one of the rarest locally aggressive growing benign tumor entities. We present an overview of the literature and a rare clinical case of a 22-year-old female patient, who was diagnosed with aggressive DF in the left pharyngeal wall at the age of 4 years old.

The adult orthodontic patient over 40 years of age: association between periodontal bone loss, incisor irregularity, and increased orthodontic treatment need.

OBJECTIVES: Adult orthodontic treatment, especially in patients over 40 years, is steadily increasing. One causal factor for the treatment need in this age group is periodontal breakdown. The aim of this study was to detect correlations between periodontal problems and orthodontic parameters in interdisciplinary patients. METHODS: This observational, cross-sectional study included 118 patients over 40 years (51 men/67 women; mean age, 58.03 years) classified into three groups according to periodontal breakdown (group I, controls; group II, moderate periodontitis; group III, severe periodontitis). Clinical periodontal and orthodontic parameters as well as the index of orthodontic treatment need (IOTN) were assessed and compared between the groups. RESULTS: A gradual deterioration of all periodontal and orthodontic parameters according to periodontal bone loss (lowest values in group I; highest values in group III) was observed. Especially groups I and III differed significantly regarding the overjet (p < 0.001) and the little indices of the maxilla (p < 0.001) and mandible (p < 0.010). The IOTN was highest in group III: 90% of the patients with severe periodontitis were classified to have moderate to very great treatment need. CONCLUSIONS: The higher the degree of periodontal breakdown was, the more severe were overjet, overbite, irregularity of the anterior teeth, and the orthodontic treatment need. CLINICAL RELEVANCE: Adult patients over 40 years represent a challenge for an orthodontic/periodontal treatment approach with high incidence of pathologic tooth migration, orthodontic treatment need, and periodontal breakdown. Therefore, this special patient collective requires a focus in clinical orthodontics and research.

Orthodontic incisor decompensation in orthognathic therapy-success and efficiency in three dimensions.

OBJECTIVES: Sufficient dental decompensation is crucial for treatment success in combined orthodontic-surgical treatment. The study's objective was to determine the treatment success and efficiency in sagittal, vertical, and transversal decompensation. METHODS: This longitudinal, observational study enrolled 52 adult patients, who underwent orthodontic-surgical treatment. Incisor inclinations and positions as well as skeletal changes were assessed pre-treatment (T1), pre-surgical (T2), and post-surgical (T3) by lateral cephalograms and CBCT scans. RESULTS: Incisor decompensation was insufficient in all three dimensions. Sagittal: treatment efficiency did not differ between class II and III patients. Vertical: patients with open bite demonstrated pre-surgical bite deepening and insufficient surgical reduction of the maxillomandibular plane angle. Transversal: Dental midline deviations were not adapted to the skeletal asymmetry so that menton deviations were not properly corrected. CONCLUSIONS: Incisor decompensation was not as successful as requested in all three dimensions and the treatment ideal was seldom achieved. CLINICAL RELEVANCE: To improve the skeletal outcome, the orthodontist has to treat the patient with the desired surgical movements in mind and should critically evaluate the pre-surgical incisor decompensation before referral to the surgical team.

TMJ pathomorphology in patients with JIA-radiographic parameters for early diagnosis.

BACKGROUND: Juvenile idiopathic arthritis (JIA) is often accompanied by pathomorphological changes to the temporomandibular joint (TMJ). By analyzing orthodontical orthopantomograms of JIA patients the aims of the study were a) classification of condyle changes, b) quantification of bony asymmetries of condylar destruction and c) detection of relationships between disease duration and TMJ-involvement. PATIENTS/METHODS: 46 caucasian JIA-patients (28 female; 18 male; < 16.0 years) were enrolled, each joint (n = 92) was morphologically assessed by means of orthopantomogram, quantitatively analysed and compared with duration of general disease. Condyle morphology was assessed using the Billiau scale for severity of destruction [1]. The quantitative analysis was based on ratios of condyle, ramus and mandible height. RESULTS: Patients were divided into groups (Group I - slightly affected, n = 36; Billiau severity 0-2; condyle findings: X-ray normal, condyle erosions, condylar flattening; Group II - severely affected, N = 10; Billiau severity 3-4; condyle findings: condylar flattenings and erosions, unilateral/bilateral complete loss of condyles), based on morphological analysis of condylar destruction. Duration of disease was significantly longer in Group II (8.9 ± 5.2 years) than in Group I (4.6 ± 4.7 years). Asymmetries of condyle, ramus and mandible height, quantitatively analysed by contralateral comparison, were significantly more marked in patients of Group II than of Group I. CONCLUSIONS: Orthopantomogram imaging can be used in orthodontics clinical routine to detect TMJ-pathologies and is an important reference for monitoring progression of JIA. Classification into severe and slightly affected TMJ is possible by analysis of condylar pathomorphology. An association between degree of destruction, extent of lower jaw asymmetry and disease duration is suggested by the results.