Evaluation of orthodontic treatment success in patients with pronounced Angle Class III.

The aim of this study was to assess the success of orthodontic treatment of pronounced Angle Class III malocclusions. The records of 16 patients with pretreatment mesial occlusion and negative overjet were analyzed by evaluating the plaster casts and lateral cephalograms made at the beginning (B1) and end (B2) of active treatment, which was purely orthodontic in all cases. After treatment the patients were divided into 2 groups: group 1 (n = 10) with virtually ideal occlusal relationships, and group 2 (n = 6) where this was not the case. Professional assessment of the results using the Peer Assessment Rating (PAR) Index revealed a reduction of the weighted PAR scores of 90.2% in group 1 and 68.8% in group 2. A questionnaire was specially designed to obtain information on the patient's rating of the treatment and of the treatment outcome. 75% of the patients addressed answered the questionnaire. Following correction of the frontal crossbites, both groups displayed a clear-cut improvement of the sagittal lip relationship; this sometimes had a striking effect on the facial esthetics. The size and heterogeneity of the sample permit only cautious interpretation of the results. However, the study suggests from what degree of Angle Class III malocclusion surgical intervention is more likely to be indicated, although the final decision on elective surgery of this kind must always be left to the patient. The PAR Index offers various advantages in assessing treatment results. However, in view of its lack of esthetic sensitivity, it should be supplemented by other assessment methods.

Matrix isolation applied to the 252Cf plasma-desorption mass spectrometry of underivatized oligosaccharides.

A number of different low molecular weight and volatile compounds have been tested and compared as matrices in 252Cf plasma-desorption mass spectrometry (PDMS) measurements of oligosaccharides. Some heteroaromatic amines (2-aminothiazole and 3-aminopyridine), hydroxyanthraquinones (alizarin and quinalizarin) and phthaleins (fluorescein) proved to be especially suited to enhancing the quasimolecular ion intensity of oligosaccharides. Discrimination effects could be reduced by matrix addition and thus, quantitative results of PDMS could be improved. Oligosaccharides with broad molecular weight distribution (dextrin 10 and dextran T 1.5) have been successfully analyzed by PDMS. The mass spectra obtained compared quite well with ion chromatograms of the respective oligosaccharides.