Orthodontic treatment is occasionally a discomfort to patients, due to pain or functional restrictions. In this context, several retrospectively planned studies were performed in the 1980s, but correlations between different aspects of patient discomfort were not investigated. The present study aimed at examining and structuring the psychogenic dimensions of patient discomfort. Furthermore, the impact of the patient's attitude on the intensity of discomfort was to be evaluated in addition to the influences of appliance therapy. The study was performed with 67 patients aged from 9 to 32 years. Prior to insertion of a new appliance, psychogenic scales reflecting their attitude towards orthodontic therapy were submitted to them. They were instructed to keep a discomfort log during the first 7 days after insertion. After 6 months they were given lists for retrospective assessment of discomfort and an appliance-acceptance scale to be filled in. At the same time, the respective orthodontist assessed his patient's compliance on a cooperation scale. The factor analysis revealed 3 levels of patient discomfort: feelings of tension, functional restrictions and aversion to wearing an orthodontic appliance in public. Appliance acceptance after 6 months could be predicted from the attitude towards treatment and the experienced discomfort. Patient compliance also correlated with these factors, so that causal flow diagrams of the investigated variables could be produced. Giving detailed information on any discomfort occurring and explaining how to reduce or eliminate it are vital factors in good treatment cooperation.

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The aim of the study was to assess pre-treatment cephalometric parameters and measurements of the size of the apical bases as predictors of successful orthodontic correction of Class III malocclusions. Pre- and post-treatment lateral cephalograms and study models of 80 completed Class III subjects were examined to obtain 23 cephalometric parameters taken mainly from the analyses of McNamara and Schwarz, and to measure the size of the apical bases. Success of occlusal correction was evaluated as the percentage change of peer assessment rating score during treatment, which was used as the dependent variable in multivariate statistical analyses testing the predictive value of the parameters assessed. No improvement in the Class III skeletal pattern occurred during treatment and the treatment effects were confined to dentoalveolar changes. With the exception of the percentage midfacial length/mandibular length ratio, the net sum of maxillary and mandibular length differences, the mandibular ramus height/mandibular body length ratio and the gonion angle, most cephalometric parameters of pre-treatment craniofacial morphology assessed were poor predictors of successful correction of Class III malocclusions. Assessment of the size relationship of the maxillary and mandibular apical bases was the strongest predictor of occlusal correction achieved and may serve as a valuable diagnostic addition in the prediction of successful treatment outcome.

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Thanks to their capability for post-processing of image data, the digital radiological techniques introduced from 1970 onwards permit dose reduction with no loss of clinical information. The aim of this study was to establish the extent of possible dose reduction in orthodontic lateral cephalography. For this purpose, lateral cephalograms of a head phantom taken with varying radiation doses (5 to 150 mAs, constant 70 kV) were evaluated. The evaluations of ten judges were compared statistically. Conventional lateral cephalograms showed a statistically proven superiority of a number of exposure parameters for the sagittal and vertical localisation of reference points. This correlated with the radiological density of the structures. In contrast to the conventional technique, the reference points in all images obtained by digital luminescence radiography showed no such tendency. Digital luminescence thus meets the clinical need to reduce radiation dose (to about 20% of the usual dose) while providing no less diagnostic information.