Kohsuke Ohno

In order to undertake a quantitative evaluation of balance occlusal load, the use of the Dental Prescale System was investigated. The method uses a test sheet that undergoes a colour-developing chemical reaction, for detecting contact area, and a computerized analysis system, for evaluating the balance of occlusal load. Twenty natural dentate subjects and 10 hemimaxillectomy patients participated in the study. Each subject bit a test sheet as hard as possible for 3 s. The balance of occlusal load was expressed as a percentage of the load on the side with the lesser occlusive load (%OLR). The %OLR ranged from 39.7% to 49.4% in the natural dentate subjects, and from 0% to 31.3% in the hemimaxillectomy patients at their resection site. The patients' low %OLRs were attributed to loss of sustaining structure and subjective occlusal adjustment by clinicians. Combining technical simplicity, relatively high reproducibility, and diverse analysis capability, this system is useful for quantitative evaluation of balance of occlusal load in clinical situations.

Structural and morphometric investigations of the vessels of the neck region were carried out on 30 cadavers (15 male and 15 female in the age range of 45 to 93 years old) to gain more knowledge of the anatomy for microvascular surgery. Our results briefly are as follows: (1) The non-common-truck type of the external carotid artery (in which each branch arises separately from the external carotid artery) was found in 76.6 percent of cases, the truncus linguofacialis type was found in 21.7 percent, and the truncus thyrolingualis type was found in 1.7 percent. (2) The smallest internal diameter (the average was 1.2 mm) was found in the superficial cervical artery. (3) The largest internal diameter (4.4 mm) was measured in the external carotid artery. (4) The longest arterial section (127.8 mm) was measured between the clavicle and mandibular margin. This vascular section or stem consisted of three parts: the supraclavicular part of the common carotid artery, the proximal section of the external carotid artery, and the first 3 cm of the facial artery. (5) In 46.6 percent of cases, the facial, lingual, and superior thyroid veins joined together and formed a thyrolinguofacialis vein. (6) The type with one external jugular vein accounted for 83.0 percent of cases, and the type with one anterior jugular vein for 67.4 percent of cases. (7) The middle thyroid vein exhibited the smallest internal diameter (average of 2.0 mm). (8) The largest internal diameter (7.9 mm) was measured in the internal jugular vein. (9) The longest vessel to receive a vascular pedicle vein was the external jugular vein, the average length of which was 99.7 mm. (10) The frequency and location of valves in the facial vein were also determined.