The lingual surface of the upper first and second molars was metrically investigated. Four parameters were analyzed, i.e., the maximum and minimum lengths of the lingual surface in the mesiodistal direction, their ratio expressed as (min./max.) ×100, and the angle formed by these two lengths, representing cervical constriction. The two lengths were larger in males than in females for both the first and second molars. The ratio was significantly larger for the first molar than for the second molar. It was consequently suggested that cervical constriction was stronger in the first molar than in the second molar. The angle did not show any significant differences either between the sexes or between the two kinds of molar.

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Rats were pretreated with either carbidopa (25 mg/kg 30 min previously) or phenelzine (50 mg/kg 18 h and 12 mg/kg 90 min previously) before being given 5-HTP (150 or 350 mg/kg) or paroxetine (12 mg/kg). In carbidopa-treated animals, 5-HTP (150 mg/kg) evoked many wet-dog shakes (WDS) without changing receptor numbers, but an increase in the dose of 5-HTP to 350 mg/kg paradoxically increased the number of cortical 5-HT₂ receptors. The increase was reversed by pretreating the rats with haloperidol (5 mg/kg), but this did not occur withα-methyl-para-tyrosine (250 mg/kg 16 h and 4 h before carbidopa). Apomorphine (2 mg/kg) in phenelzine-treated rats and apomorphine (10 mg/kg) in untreated rats increased 5-HT₂ receptor numbers. The reason for the failure of 5-HTP to rapidly down-regulate 5-HT₂ receptors is not known, but is thought to depend in some complex way on the proportion of 5-HTP that is decarboxylated to 5-HT outside serotonergic neurons, thus affecting the dopaminergic mechanism. In phenelzine-treated rats, paroxetine produced a 5-HT-dependent syndrome, which included WDS, and a significant reduction in cortical 5-HT₂ receptors within 3 h. WDS were unaffected by administration of propranolol (20 mg/kg) or pindolol (5 mg/kg), confirming that WDS were independent of 5-HT_1A receptors. The reduction of 5-HT₂ receptors was not associated with migration of the receptors into the “light-density fraction” of the cortex, isolated by density-gradient centrifugation.

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The microbial compositions of subgingival plaque and the clinical indices of periodontal tissues were analyzed using a quantification method of the first type and multiple regression analysis to determine the feasibility of predicting the progress of periodontal disease on an objective basis from homogeneous microbial data. The results suggested that objective information on the progress of periodontal disease could be obtained by surveying the subgingival microflora and subjecting the data to numerical analysis.

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The profiles of the face and upper central incisor tooth surface are known to be similar. This study evaluated the accuracy of an image-analysis device, which was then used for quantitative analysis of facial and tooth profiles.
The device consisted of a CCD TV camera, a shade corrector, a video recorder, an image-analyzer (PIAS Co., Model LA-500) and a microcomputer (NEC Co., Model PC-9801 VX 2).
Squares (150mm×150mm and 10mm×10mm) and a metal coin (diameter 20 mm) were used for evaluation of the system's ability. The measurement procedures were as follows : 1) The squares and the coin were measured to obtain values of area and perimeter length, and 2) study models of 6 volunteers, 1 female and 5 males, between the ages of 25 and 30 years, were assessed by measurement of individual face and tooth profiles.
The average error rate was less than 5% for the squares and the coin. The average ratio of the long axis of the face to that of the tooth was 1/19, and that of the short axes 1/16.

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