Cell-adhesive glycoprotein, which is in the cell and extracellular matrix, may be di-rectly involved with attachment of odontoclasts to the root surface. The left maxillary first molars of 12- to 13-week-old Wister rats were moved by the Waldo method to observe root resorption and localization of vitronectin immunohistochemically on the tension side of the molars. The teeth were divided into two groups according to the thickness of elastic bands used. Group A had 1mm×1mm×0.65mm bands, and group B had 1mm×1mm×1mm bands. Vitronectin was not detected on the tension side after 1 or 3 days tooth movement in either group. After 5 and 7 days, odontoclasts were observed on root surfaces of the tension side and vitronectin was detected ; the former, on the circle of spot-like absorption, and the latter, con-tinuously, on the surface of widespread absorption. Root resorption was less frequent in group B, while the amount of vitronectin detected was the same in both groups. Although, vitronectin was not detected the control side in either group, there was widespread bone resorption by osteoclasts in both. Thickness of the elastic bands had little effect on the localization of vitronectin. It was con-cluded that root resorption and the subsequent localization of vitronectin on the root surfaces at the tension side was more influenced by time than by strength of the orthodontic force.

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We examined the effect of midazoram on the increase in orofacial pain induced by measuring extracellular dopamine in the prefrontal cortex using in vivo microdialysis. Rats were anesthetized and a microdialysis probe was implanted into the left prefrontal cortex. After one week, Ringer's solution was perfused in the probe at a flow rate of 1μl / min, and samples were collected every 20 min. Samples were injected immediately into a high performance liquid chro-matography system with an electrochemical detector. Electrical stimulation of the upper lip elicited an increase in the concentration of dopamine. Midazoram (0.15mg / kg, i. v.) decreased the pain-evoked increase in the dopamine concentra-tion. These findings suggest that orofacial pain increases dopamine in the prefrontal cortex, and that midazoram inhibits this increase.

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In order to investigate the efficiency of minocycline (Periocline^®) and Periocline^® with DNase containing fibrinolysin (Elase^®) in periodontal pockets of adult periodontitis, I compared the periodontal index and bacterial changes of patients receiving no treatment (Group A, con-trols), those receiving Elase^® only (Group B), those receiving Periocline^® only (Group C) and those receiving Periocline^® with Elase^® (Group D). I also determined the minimum inhibitory con-centrations (MIC) of minocycline and minocycline with Elase^® against bacterial strains isolated from adult periodontitis. In all cases, the periodontal index of Group D was markedly better than that of Group C. Bacteriological examinations indicated that the total number of bacteria and ratio of anaerobic bacteria, especially black pigmented gram-negative anaerobic rods were less in Group D than Group C. Furthermore, the MIC of minocycline with Elase^® against the strains tested was lower than with alone. These results suggest that administration of Periocline^® with Elase^® in periodontal pockets of adults with periodontitis is more effective than administration of Periocline^® alone.

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Because T and NK cells infiltrate inflammatory gingival tissues during periodontal dis-ease, a local immunoresponse is believed to be involved. I investigated the costimulatory effects of CD 2 stimulation on IL-2-mediated NK cell proliferation and signal pathways through CD 2 and IL-2 using the NK cell line, NK 3.3 cells. Costimulation of CD 2 crosslinking significantly en-hanced IL-2-mediated NK 3.3 cell proliferation. Crosslinking of CD 2 induced tyrosine phospho-rylation of protein tyrosine kinase, Syk and the adapter proteins, Shc and Cbl. However, IL-2 stimulation enhanced tyrosine phosphorylation of Shc, but not Syk or Cbl. Cbl constitutively as-sociates with Grb 2 through the N-SH 3 domain, whereas Shc associates with Grb 2 through the SH 2 domain in an activation-dependent manner.

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I studied β-lactamase, outer membrane permeability (OMP), and efflux of drugs to elucidate the role of the β-lactam antibiotic resistance of Prevotella intermedia MA 1-V2. β-Lactamase activity in the periplasmic space was 57〜88% inhibited by 0.25〜8μg / ml of 3 β-lactamase inhibitors. The inhibitors and β-lactams were added to cultures and the treatment continued for 0.5 hours. The β-lactamase antivity was inhibited 80〜96%. The inhibitors (clavu-lanic acid and tazobactam : 0.5μg / ml, sulbactam : 1μg / ml) and β-lactams (piperacillin and cefteram : 128μg / ml, cefazolin : 64μg / ml) were added to the cultures 3 hours after inoculation, decreasing the viable count. The MIC of 3 the β-lactams with inhibitors was decreased 1 / 512〜1 / 16. I also studied the effect of OMP on the MIC of β-lactams with ethylenediamine tetraacetic acid disodium salt, and measured the viable count with cyanide m-chlorophenylhydrazone to study drug efflux. No decrease was detected in either the MIC or viable count. These results suggest that lactamase activity in the periplasmic space was inhibited, causing a decrease in the viable count and MIC. This implies that β-lactamases are the most important factor in the β-lactam resistance of this strain.

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Anatomical and biological studies indicate that the phylogenetic development and on-togeny of the human comprise a number of important environmental factors that are implicated in evolutionary and devolutionary transitions of the stomatognathic system. Normal occlusion is one of the basic concepts of normal stomatognathic function. There are several essential static and dynamic aspects in the anatomy of ideal occlusion, as well as morphological and physi-ological features.

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Orthodontists are very aware of occlusion in the static sense. They define it as the normal relation of the occlusal inclined planes of the teeth when the jaws are closed. Normal oc-clusion is a goal of orthodontic treatment, in addition to the spatial position of the teeth and arches in the cranial face. A trend from static to dynamic considerations in occlusion has been brought about by the development of new measurement devices. Thus, the original static con-cepts of occlusion have given way to broader dynamic interpretations.

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Centric occlusion and intercuspal position are generally defined as the centered con-tact position of the occlusal surfaces of the mandibular teeth against the occlusal surfaces of the maxillary teeth. However, 'centric occlusion' is defined in the Glossary of Prosthodontic Terms, 6th edition as 'the occlusion of opposing teeth when the mandible is in centric relation. This may or may not coincide with the maximum intercuspation'. The terms that express mandibular posi-tion are ambiguous. In particular, the definition of 'centric relation' has changed over time. It has been considered the most posterior position for reproducible transfer recording purposes. The question arose as to whether the position of centric relation was biologically acceptable. I con-cluded that centric relation is the most anterior-superior position of the mandible that is physi-ologically acceptable. This paper discusses centric occlusion and presents a definition.

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Intercuspal position is the most important functional mandibular position of the sto-matognathic system. We attempted to clarify maximum intercuspation in normal subjects using the T-Scan system and the Add-Picture method, which applied computer image processing to a silicone occlusal record. We obtained the following criteria for normal intercuspation: 1. Bilateral contacts between the maxillary and mandibular posterior teeth during light clenching. 2. The same situation during medium clenching. 3. No displacement of teeth contacts between the two clenching pressures. 4. Equal occlusal force at each tooth contact. 5. Simultaneous contact.

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Excessive alveolar bone resorption is an obstacle to denture treatment. We evaluated how evaluated how α-TCP with collagen sponge and α-TCP processed with tannic acid improvws bone configuration. Defects were artificially made in the alveolar bone of Japanese monkeys and were filled with the above materials. At 2, 4, and 8weeks after placement of the material, microvascular casts were made for observation by scanning electron microscope. α-TCP processed with tannic acid promoted dense capollaries and markedly enhanced bone healing. The results indicated that application of this material in bone defects should be useful in promoting alveolar bone formation for denture treatment.

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