Ivar Espelid

Caries assessment and restorative treatment thresholds reported by Swedish dentists.

The aim was to study any variability in approximal and occlusal caries diagnoses and restorative treatment decisions among Swedish dentists. The material consisted of a pre-coded questionnaire sent to a random sample of 923 dentists with 4 items concerning approximal and occlusal caries diagnosis and restorative treatment decisions. Responses were received from 651 (70.5%) dentists. In an adolescent with low caries activity and good oral hygiene, more than 90% of the dentists stated that they would not automatically restore a primary approximal caries lesion if its radiographic appearance did not show obvious progression in the outer 1/3 to 1/2 of the dentin. Moreover, 67% of the dentists would only consider immediate restorative treatment of an occlusal surface if obvious cavitation and/or radiographic signs of dentin caries could be observed. When diagnosing questionable occlusal caries, the dentists largely relied on the radiographic appearance. Concerning both approximal and occlusal caries, the threshold for restorative treatment differed between the metropolitan regions in Sweden, and younger more often than older dentists would postpone restorative treatment of approximal caries until the lesion had reached a relatively advanced stage of progression. The responses also showed that dentists in private practice would restore approximal caries at an earlier stage of progression than the dentists in the Public Dental Health Service.

EMG feedback in the treatment of myofascial pain dysfunction syndrome

The effect of electromyographic (EMG) biofeedback on frontalis and masseter muscle activity was compared with control conditions in two groups of patients with a diagnosis of myofascial pain dysfunction (MPD) syndrome. Patients were selected on the basis of clinical symptoms, radiographic evaluation, and a clinical examination. Depressed patients and patients with signs of a pathological condition in the temporomandibular joint were excluded. Both the experimental (EXP) and the control (CON) group went through two base-line screening sessions before treatment of the EXP group was started. Treatment consisted of eight biofeedback sessions, given twice a week for 4 weeks. Feedback was presented visually on a monitor. Treatment did not include any relaxation training. Control evaluations of both groups took place 1 week, 3 months, and 6 months after the end of treatment. The EXP group was able to reduce EMG levels in frontalis and masseter muscles significantly during training sessions. Follow-up data showed significantly reduced frontalis EMG levels in the EXP group after 3 and 6 months but not in the CON group. Both groups improved subjectively, as judged by reports on pain intensity and duration, but this improvement was significantly more pronounced in the EXP group. Objective clinical indices recorded throughout the study were uncorrelated with EMG changes or subjective reports. It is concluded that biofeedback training facilitated muscular relaxation and self-regulation in the EXP group and that visual EMG feedback, consisting of a patterning of frontalis and masseter muscle activity, can be recommended as an integrated part of MPD syndrome treatment.

Diagnostic quality and observer variation in radiographic diagnoses of approximal caries

The aim of the study was to compare observer variations, observer strategy, and diagnostic quality with regard to radiographic caries diagnoses made at different depth levels. Qualitative assessment of approximal carious lesions on the basis of radiographs were made for sound (n = 28) and carious (n = 123) lesions by seven dentists. The inter- and intra-observer variations were lowest when lesions were diagnosed as being in the outermost parts of the teeth. The frequency of false positive scores was lower when dentin was examined as compared with enamel. The quality of radiographic diagnoses showed small variations (p greater than 0.05) when different levels of pulpal depths were interpreted.

A comparison of radiographic occlusal and approximal caries diagnoses made by 240 dentists

Radiographs of occlusal (n = 20)and approximal (n = 24)surfaces of extracted teeth were examined by 240 dentists before participating in continuing education courses dealing with caries diagnosis and treatment decisions. The radiographic caries diagnoses were treated in accordance with the receiver operating characteristic (ROC) technique, in which the area beneath the ROC curve (Az value) indicates the quality of the observations. The frequencies of false positives made in dentin radiographically were higher for approximal (20.7%) than for occlusal caries (12.3%). The quality of pooled radiographic diagnoses of occlusal dentin lesions for all observers was significantly better than diagnoses of approximal caries in dentin. A statistically significant relationship between the observers qualities of diagnosis of caries on approximal and occlusal surfaces (P = 0.045) was found. For diagnosis of dentin caries on approximal surfaces the mean Cohen kappa was 0.74 (standard deviation (s), 0.12; range, 0.39-0.95), and the corresponding values for occlusal surfaces were 0.70 (s, 0.14; range, 0.25-0.98). In the material under study the dentists were at least as good at diagnosing dentin caries occlusally as approximally. To avoid overtreatment, the observers diagnostic threshold should ideally be adjusted towards strict criteria when a positive diagnosis is synonymous with a filling. The diagnostic thresholds were stricter in diagnosing occlusal surfaces than for approximal surfaces, indicating a more optimal strategy among dentists while diagnosing occlusal dentin lesions in a population with low caries prevalence.

Radiographic Diagnosis of Mineral Loss in Approximal Enamel

The relationship between mineral loss in approximal enamel and the precision of the radiographic diagnosis was investigated using experimental lesions and Receiver Operating Characteristic (ROC) techn

The influence of viewing conditions on observer performance in dental radiology

Observer performance under different viewing conditions was monitored by means of radiographs, showing teeth with approximal caries, teeth with simulated approximal caries, and Plexiglas phantoms. Series a and c were exposed at two different exposure times, thus obtaining a dark and a light set of radiographs. The series a, b, and c were read by 11, 2, and 5 observers, respectively. All radiographs were examined under two viewing conditions on different occasions as follows: ceiling light in a room without a window, and X-ray viewer (X 2 magnification) with two alternative light sources. Diagnostic quality, measured as the ROC area, showed small variations in accordance with viewing conditions. For dark radiographs the X-ray viewer improved diagnostic quality compared with the viewing against ceiling illumination; however, room illumination provided the best viewing conditions when light radiographs were examined. Most of these differences were not statistically significant (p greater than 0.05). Only small differences in diagnostic strategies (cut-off points) were recorded between viewing conditions.