Biomedical subjects

G Boering

Publications and source records attributed to G Boering.

At least 55 records · Page 3Linked to original sources

PubMed1994

Joint mobility measurements: reliability of a standardized method.

Assessment of hypermobility and hypomobility is frequently performed visually with all its limitations. In this study, a standardized joint mobility measurement method is suggested, and its reliability is tested. The maximal range of motion of passive digit five hyperextension, passive thumb apposition to the wrist, active elbow and knee hyperextension, active ankle dorsal flexion and trunk flexion was measured in 30 healthy subjects. All measurements were performed bilaterally, except for trunk flexion. Three experienced observers performed the measurements according to a rigidly standardized protocol, using appropriate goniometers and rules. During one measurement session each observer measured each subject. Two consecutive measurement sessions were organized. Analysis of variance, with subject and time as explaining variables, was performed on the data obtained. The inter-observer variability ranged from 1.42 degrees (left knee hyperextension) to 4.05 mm (right thumb apposition) in the first measurement session and from 1.35 degrees (left knee hyperextension) to 4.58 degrees (right digit five hyperextension) in the second measurement session. The intra-observer variability ranged for observer A from 0.75 degree (left knee hyperextension) to 3.67 mm (left thumb apposition), and from 0.93 degree (left knee hyperextension) to 3.88 degrees (left digit five hyperextension) for observer B. Observer C ranged from 0.71 degree (left knee hyperextension) to 4.01 mm (right thumb apposition). Based on the results of this study, the authors conclude that joint mobility can be measured reliably and accurately with the presented simple tools.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Histologic evaluation of computed tomographic TMJ articular disk visualization.

The reliability of computed tomography (CT) for visualization of the temporomandibular joint (TMJ) articular disk has often been the subject of discussion. The success or failure of CT may be determined by different factors. This study was designed to evaluate the effect of these factors, such as type of equipment used, patient motion and artifacts on articular disk visualization, and also to assess the validity of the articular disk image in comparison with histological pictures. Ten TMJ autopsy specimens were collected after the teeth were placed in intercuspal position. The TMJ was deep frozen, dissected and kept frozen during subsequent CT scanning and histological processing. To study the influence of the specifications of the CT equipment on the visualization of the TMJ articular disk, two different CT units were used. The CT images were evaluated for interpretability and interpretation of articular disk position. The validity of the CT appearance of articular disk position and form was assessed by superposition of CT and histological pictures. The interpretability of the articular disk visualization in the CT images was very low. However, for CT images judged to be interpretable, there was a good degree of matching between the diagnosed articular disk position and form and the findings in the corresponding histological pictures. No significant differences between the two different CT units were noted. It is concluded that CT is inappropriate for TMJ articular disk visualization. Nevertheless, if the disk is visible on the CT image, its appearance represents the true position and form within the joint.

Adult↗

PubMed1994

The relationship between temporomandibular joint mobility and peripheral joint mobility reconsidered.

The purpose of this paper was to study the relationship between temporomandibular joint (TMJ) mobility and mobility of joints and to study the general character of joint mobility in 83 subjects, 55 females and 28 males (mean age 26.7, range 13-46 years). The subjects were recruited from the Department of Oral and Maxillofacial Surgery of the University Hospital of Groningen. All participants had a good general health and did not present anamnestically, clinically or radiographically TMJ disorders. Of these subjects, angular displacement of the mandible relative to the cranium during maximal mouth opening (AMO) was measured. Furthermore, the maximal range of motion of passive digit five hyperextension, passive thumb apposition to the wrist, active elbow and knee hyperextension, active ankle dorsal flexion and trunk flexion were measured. All measurements were performed bilaterally, except trunk flexion. Calculation of product moment correlations (Pearson) revealed a weak relationship between AMO and mobility of right digit five and elbows for the total group and between AMO and mobility of both digits five and elbows for women. The correlations were never stronger than 0.4. Multiple regression revealed that only 25.9% of the total variance of AMO could be explained by mobility of peripheral joints, age and sex. Calculation of product moment correlations between mobility of peripheral joints, trunk flexion and age revealed weak correlations between the different joints, with the exception of paired joints. Principal component analysis revealed a weak general character of joint mobility.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1994

Clinical signs of TMJ osteoarthrosis and internal derangement 30 years after nonsurgical treatment.

To evaluate the clinical course of temporomandibular joint osteoarthrosis and internal derangement, 99 patients who had received nonsurgical treatment for temporomandibular problems were reexamined 30 years after the original treatment. Results were compared with information obtained from patients' clinical examinations before and a few years after the original treatment as well as information from the clinical examination of 35 control subjects. During the first years after treatment, the main signs of temporomandibular joint osteoarthrosis and internal derangement decreased significantly. In the next three decades, very few changes were noticed. Clicking and crepitus were the most common remaining signs. These signs, however, did not appear to be bothersome to the patients. It was concluded that the disorders in question eventually reach a state of quiescence.

Adaptation, Physiological↗

PubMed1993

Short-term outcome of arthroscopic surgery of temporomandibular joint osteoarthrosis and internal derangement: a randomized controlled clinical trial.

Various types of treatment have been proposed for patients with temporomandibular joint (TMJ) osteoarthrosis and internal derangement. We examined the suitability of several assessment instruments developed in previous investigations for treatment-evaluation in a clinical trial comparing arthroscopic surgery with non-surgical treatment for a specific subgroup of TMJ osteoarthrosis and internal derangement, characterized by joint pain and restricted mobility. Twenty-one patients appeared to obey strict criteria for participation, and were randomly assigned to receive arthroscopic surgery followed by post-operative physical therapy (n = 9), or non-surgical treatment (n = 12). Individual outcome was assessed immediately following treatment and after 6 months based on a priori defined criteria. Patients treated with arthroscopic surgery reported more pain relief and more improvement of mobility than patients treated non-surgically, although clinical assessment results were comparable between the two groups. No major changes were observed regarding general well-being and interference with daily activities. The results of this pilot study indicate that the assessment methods are sufficiently sensitive for changes in pain, mobility, and functional ability. Despite the higher degree of subjective pain relief and appreciation of improvement of mobility in the arthroscopic surgery group, with these more formal assessment instruments this difference could not be confirmed. It is concluded that the preliminary results should be verified in a larger trial with a slightly adjusted design.

Adolescent↗

PubMed1993

Computed tomography in differential diagnosis of temporomandibular joint disorders.

Computed tomography (CT) has great potential for imaging intra- and extracapsular hard-tissue abnormality of the temporomandibular joint (TMJ). CT is not the best method of imaging disk position and form. For differential diagnosis of TMJ disorders, CT is especially successful in bony lesions. The study includes 16 examples of TMJ hard-tissue abnormality. In the differential diagnosis of all cases, CT played a decisive role.

Adolescent↗

PubMed1993

Temporomandibular joint osteoarthrosis: clinical and radiographic characteristics 30 years after nonsurgical treatment: a preliminary report.

Thirty years after being treated nonsurgically for osteoarthrosis and internal derangement, 14 women and seven men were re-examined clinically and radiographically. The results of this examination were compared with those recorded before and after treatment 30 years ago, and with those of a matched control group. The number and degree of subjective and objective signs and symptoms decreased, and was comparable to that of the controls. However, the patients reported significantly more pain and difficulty on opening the mouth wide. This was reflected in the radiographically assessed joint mobility, which increased significantly over the years, but was still significantly less than that of the controls. The occurrence and extent of radiographically visible osteoarthrotic alterations increased over the years, and differed significantly from those of the controls. Therefore, the authors conclude that few symptoms and clinical signs of osteoarthrosis are found many years after treatment, although radiographic alterations may be extensive.

Aged↗

PubMed1993

Temporomandibular joint osteoarthrosis and temporomandibular joint hypermobility.

For studying the relationship between condylar hypermobility of the temporomandibular joint (TMJ) and osteoarthrosis (OA), 13 patients with bilateral condylar hypermobility were evaluated clinically and radiographically, 30 years after non-surgical treatment. The evaluation included range of motion, joint and muscle tenderness to palpation, joint sounds and masticatory function. Radiographs of the TMJs were evaluated for the absence or presence of degenerative changes. The hypermobile group (HG) was compared with a control group (CG) (n = 13). The CG was evaluated in the same way as the HG. Statistics included t-tests (to compare ranges of motion in the HG over time and to compare ranges of motion in HG and CG), non-parametric tests (to compare tenderness of muscles and joints, joint sounds, masticatory function and radiographic changes over time in the HG). The tests were also used to compare the same variables between the HG and CG group. The groups' only difference was the presence of radiographic signs of OA. In the HG the number of joints with radiographic degenerative changes increased significantly over time and was significantly higher than the CG. Clinically and functionally, the HG and CG did not differ. Therefore, it is concluded that TMJ hypermobility is a subsidiary factor in the development of TMJ OA.

Adolescent↗

PubMed1993

[Radiographic diagnosis of aberrations in the teeth and tissue in the area].

Radiographic examination of the dentition and supporting bone is pre-eminently the area of expertise of the dentist. The radiographic images made with the use of a modern dental X-ray machine and high resolution dental X-rays are highly detailed and give very useful and reliable information, not only of the dentition but also of bone and its diseases in general. In this publication several examples are given of the practice of oral radiologic interpretation.

Humans↗

PubMed1993

[Radiology of the temporomandibular joint. Diagnostic imaging of the temporomandibular joint].

Diagnostic imaging plays an important role in the diagnosis of disorders of the masticatory system. The most frequent disorders are osteoarthrosis and internal derangements. The clinical diagnosis of these disorders may be confirmed by diagnostic imaging. In addition, diagnostic imaging contributes to the staging of the degenerative changes. Techniques for examination of the temporomandibular joint, including conventional (panoramic, transpharyngeal, transcranial) as well as more sophisticated techniques (tomography, fluoroscopy, arthrography, computed tomography, scintigraphy and magnetic resonance imaging) are briefly described. The interpretation of the radiological image of the joint in health and when affected by osteoarthrosis and internal derangement is presented.

Humans↗

PubMed1993

Assessment of mandibular function impairment associated with temporomandibular joint osteoarthrosis and internal derangement.

Clinical assessment of function impairment associated with temporomandibular disorders should not only comprise diagnostic assessment of symptoms and signs but also function impairment assessment in the patient's value system. Regarding clinical assessment methods, the range of opening movement has been demonstrated to be one of the few variables that can be measured reliably. However, this variable allows no distinction to be made between articular and muscular causes of movement restriction. To assess joint mobility, a combination of indirect and direct assessments is proposed, including the range of opening movement after passive stretch, the range of horizontal excursion toward the opposite side, and the condylar translatory capacity by palpation. In clinical practice, signs and symptoms needed for diagnosis are frequently used as the only basis for mandibular function assessment. Function assessment in the patient's value system, however, is a neglected area in outcome assessment. The main objective of this study was to design and clinimetrically evaluate a mandibular function impairment questionnaire. The relationship between jaw function impairment and measures of pain, movement restriction, and psychological distress was assessed. The questionnaire appears to be a reliable and valuable complementary tool for assessing mandibular function impairment.

Activities of Daily Living↗

PubMed1993

Temporomandibular joint pain assessment.

The aim of this study was to evaluate pain characteristics of patients with temporomandibular joint-related pain and propose a rationale for the assessment of pain and its impact on patients with temporomandibular disorders. Based on anamnestic information, the 88 patients in the sample were classified according to pain grade: (1) acute/subacute nonrecurrent or recurrent pain, n = 41 (46.6%); (2) persistently recurring pain in relatively high frequency, or nonsevere persistent pain, n = 32 (36.4%); (3) persistent and impairing pain, n = 8 (9.1%); (4) persistent and disabling pain, n = 7 (7.9%); and (5) persistent and handicapping pain, n = 0. Regarding TMJ pain provoked during the clinical examination, there was a significant difference among diagnostic subgroups, subgroups with different pain intensity levels, and pain grade subgroups, but no significant differences could be found based on the duration of the pain symptoms. Subgroups also did not significantly differ in scores on the Multi-dimensional Pain Inventory and the General Health Questionnaire. Based on the results of the study, the assessment of nonchronic TMJ pain may generally be limited to an accurate description of the pain complaint and thorough clinical assessment. Multidimensional assessment may be useful when the TMJ pain persists or is persistently recurring. Depending on individual circumstances, additional assessment procedures may prove to be useful. A general strategy for pain assessment in temporomandibular disorders is proposed.

Adolescent↗

PubMed1992

Secondary retention of permanent molars: an assessment of ankylosis by scanning electron and light microscopy.

Secondary retention refers to the cessation of eruption of a tooth after emergence. This may be the result of pathological changes in the periodontal ligament. The aim of this study was to describe the morphological and histological aspects of the radicular surface of secondarily retained permanent molars. The roots of 12 secondarily retained molars and two control molars, were examined by means of scanning electron microscopy (SEM) and light microscopy (LM) in order to analyse the occurrence and localisation of ankylosis. With SEM it was observed that the root surface of retained molars showed local areas covered with bonelike tissue. LM of these areas showed that this tissue was bone in direct contact with the root surface (ankylosis). In 11 cases, the areas of ankylosis were observed in the bifurcation area and at the interradicular root surface. In the remaining case, ankylosis was located at the outer root surface. The results of this study endorse the assumption that focal ankylosis is an important factor in secondary retention. Treatment recommendations must be based on this fundamental principle, because orthodontic movement of ankylotic molars is not possible.

Adolescent↗

PubMed1992

Three-dimensional visualization of the temporomandibular joint: a computerized multisectional autopsy study of disc position and configuration.

To demonstrate disc position and disc configuration of the temporomandibular joint, three-dimensional multisectional computer reconstructions were made of 20 autopsy specimens (11 female, 9 male; mean age, 40.4 years). The presence of a distinct occlusion was the only criterion for selection. Normal disc position was found in 13 joints, partial anterior disc position was found in 5 joints, and complete anterior disc position was seen in 2 joints. Fifteen joints had biconcave disc configuration and 5 joints had deformed discs. Considering the high incidence of disc position deviating from the normal superior position, it is suggested that in some cases a so-called abnormal disc position can be regarded as within the limits of anatomic and physiological variability.

Adult↗

PubMed1992

Secondary retention of permanent molars: a report of five families.

The aetiopathogenesis of secondary retention is not fully understood, but heredity is involved in at least some cases. In this study first-degree relatives of 52 patients with secondary retention of permanent molars were screened for the presence of the same phenomenon in their dentition. Familial occurrence could be shown in five families. The pedigrees are compatible with autosomal dominant inheritance. HLA phenotypes and blood groups ABO, rhesus and P1 were studied in two families. The lod scores for linkage with secondary retention were added to previously reported information. The lod score for linkage for blood group system P increased from +0.940 to +1.475 at a recombination fraction of 5 per cent. It is concluded that secondary retention of permanent molars is an aetiologically heterogeneous condition in which some cases are caused by the presence of an abnormal autosomal dominant gene.

Adult↗

PubMed1992

Computer-aided optimization of choice and positioning of bone plates and screws used for internal fixation of mandibular fractures.

The present study describes a biomechanical integrated model of the mandibular system in which the maxilla and mandible, the masticatory muscles, and the temporomandibular joints are regarded as one system. In this model, strains in plate-osteosynthesis devices for internal fixation of mandibular fractures can be minimized by optimizing their positions. The model evaluates maximal bite force strategies on all possible dental elements; it uses a linear programming technique and a muscle architecture model, resulting in muscle recruitment patterns. The shape of a "standard" lower jaw is digitized by means of a three-dimensional (3-D) coordinate retrieval device and drawn on a computer screen after its dimensions have been changed according to the clinical case at hand. The 3-D location of the fracture as well as the anatomic restrictions for screw placement can be indicated on the screen. Osteosynthesis devices can be indicated in terms of dimensions, number, and material properties.

Biomechanical Phenomena↗

PubMed1992

Classification of temporomandibular joint osteoarthrosis and internal derangement. 1. Diagnostic significance of clinical and radiographic symptoms and signs.

In the clinical setting, diagnosis primarily depends on the history and present status of the patient, and on the examiner's expertise in physical examination and interpretation of conventional radiographs. In order to evaluate the diagnostic significance of clinical and radiographic variables, the authors used magnetic resonance imaging as the 'golden standard' for articular disk position. A total of 90 temporomandibular joints (TMJs) were available for the study. Group I (representing 'normal' disk position) comprised eight joints (8.9%); group II (representing reducing disk), 34 joints (37.8%); and group III (non-reducing disk), 48 joints (53.3%). Nine anamnestic, 15 clinical, and three radiographic variables obeyed pre-defined univariate selection criteria. Relatively high sensitivities were found for clicking-related variables in MR-group II, and for variables related to movement restriction in MR-group III. None of the symptoms or signs appeared to be pathognomonic for either one of the diagnostic groups. Principal component analysis revealed 13 factors that could be grouped into three major categories, representing impairment of joint mechanics, joint pain and tenderness, and radiographically detectable degenerative changes, respectively. Discriminant analyses showed that symptom combinations, which included clinical variables related to joint mechanics, appeared to provide the most useful diagnostic information. It is concluded that reducing and permanent disk displacement can be distinguished in many cases using clinical and radiographic variables. However, there is considerable variability within these groups. To establish a specific clinical diagnosis, a more detailed classification of osteoarthrosis and internal derangement is desirable.

Adolescent↗

PubMed1992

Classification of temporomandibular joint osteoarthrosis and internal derangement. 2. Specific diagnostic criteria.

Separate entities of temporomandibular joint osteoarthrosis and internal derangement are operationally defined. Criteria are based on an analysis of the diagnostic significance of symptoms and signs, principles of synovial joint pathology in general, and on therapeutic considerations. The primary goal was to enable identification of characteristic stages of osteoarthrosis and internal derangement using diagnostic tools readily available in practice.

Cartilage, Articular↗