[The suitability of various cephalometric planes for the determination of vertical alignment of the head]. / Die Eignung verschiedener cephalometrischer Bezugslinien für die Bestimmung der vertikalen Ausrichtung des Kopfes.

Different cephalometric lines or planes may be used to determine vertical head tilt. 94 subjects were used to assess the difference in inclination between the Frankfurt horizontal and Reid's line by means of a photographic method. We found that the inclination of Reid's line differs about 13 degrees from the inclination of the Frankfurt horizontal and depends on the subject's sex but not on their age. Hand held inclinometer are used in most studies for determining the inclination of the head. In our study different experimenters assessed the above mentioned inclinations at our 94 subject's using a hand held inclinometer. It turned out that the results depend statistically significant on the experimenter. Data were compared to the ones assessed using the photographic method. By means of an analysis of variance in which the experimenter is considered, a significant correlation (p < 0.001) between data assessed with the two different methods was found. However, only 51% of the variance can be explained by our model. Variance might be due to inaccuracy in determining some of the points defining the Frankfurt horizontal and Reid's line, i.e. the lower orbit and the centre of the outer ear channel. The inclination of another reference line running from the tragion to the outer canthus was measured using the same subjects and the same experimental procedure as mentioned above. This line is easier to determine than the Frankfurt horizontal or Reid's line as its defining points can be assessed with greater accuracy. The inclination of this differs 10.5 degrees from the one of the Frankfurt horizontal.

Skin risk assessment of metalworking fluids: a survey among Swiss suppliers.

BACKGROUND: Metalworking fluids (MWF) are the most important cause of hand dermatitis in the metal industry. The substitution of noxious products by less aggressive MWFs is therefore an important measure to reduce the incidence of hand eczema in this type of industry. In order to do so, producers and suppliers have to evaluate the skin risk of such products by predictive allergenicity and irritancy testing. OBJECTIVE: The aim of the study is to evaluate if predictive testing is performed in MWF products that are currently offered in the Swiss market and what kind of tests are applied. METHODS: A questionnaire was sent to 11 Swiss MWF suppliers in order to collect information on the actual practice of skin risk testing. RESULTS: Nine of 11 suppliers returned the questionnaire. Five suppliers report some kind of allergenicity testing in some of the products. Seven companies test for irritancy by a single application method, but only two perform cumulative irritancy testing in some products. The methods of testing (animal, human, field studies) vary greatly among the different companies. CONCLUSION: It is concluded that the practice of predictive testing for sensitization and irritancy of MWF is unsatisfactory and does not allow the user to compare products based on their skin risk. Occupational dermatologists should strive for standardization of MWF testing including so far scarcely performed repeated insult tests.

Prevention of hand eczema in the metal-working industry: risk awareness and behaviour of metal worker apprentices.

BACKGROUND: In the metal-working industry, occupational hand eczema is very common and often due to contact with cutting fluids. Since it can be avoided by adequate protective measures, prevention plays an important role. However, the effectiveness of prevention depends heavily on the employees' awareness of this health risk. OBJECTIVE: The study aimed to collect information on the attitude of metal worker apprentices towards the risk of occupational skin disorders and skin protection since it is believed that their attitude at the beginning of the education will guide their future risk behaviour. METHODS: By means of a questionnaire, 79 metal worker apprentices were interviewed about their awareness of dermal risk factors and their risk behaviour at work. RESULTS: The apprentices are very badly informed about skin diseases and skin care. Most of them are not concerned about developing occupational skin problems, and they declared having obtained very little information about this subject. CONCLUSION: Considering this finding, it seems urgent to intensify health and safety education already at the beginning of the apprenticeship.