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Three-dimensional simulation is necessary for the case that a face form is asymmetry in orthodontic treatment. Authors developed the three-dimensional measurement system which used the grid pattern projection method. And we had reported about using it for dental cast measurement. Furthermore, we applied this principle and developed the three-dimensional measurement device of a face. This report introduces the three-dimensional measurement device of the face which used the grid pattern projection method that was developed by us. And we report about clinical application of three-dimensional simulation of the face which used this device. It was difficult to predict a postoperative form of the face which was an asymmetry before. However, the patient is easy to have come to understand the change of postoperative facial form by performing three-dimensional simulation. The three-dimensional simulation was effective as a material of informed consent of the case especially that had an asymmetry facial form in orthodontic treatment.

We have shown that conditioning stimulation of the amygdaloid nucleus has an inhibitory effect on the nociceptive neurons in the tngermnal caudal nucleus and the medial reticular subnuclei of the rat The purpose of this study is to investigate whether the opioid receptor is involved in the inhibitory effect of amygdaloid stimulation of the nociceptive neurons The animals were anesthetized with N_2O-0_2 (2・1) and 0.5%-halothane, and immobilized with pancuromum bromide. The peripheral test stimulus (a single rectangular pulse of 2.0 msec in duration) was applied to the facial skin in the receptive field of nociceptive neurons, and the ipsilateral amygdaloid conditioning stimuli to the recording site were trains of 33 pulses (0.5 msec in duration, 100-300 μA) delivered at 330Hz. Fifty-six wide dynamic range (WDR) neurons and 15 nociceptive specifc (NS) neurons were recorded WDR neurons were distributed in the superficial layer of the caudal nucleus and diffusely throughout the reticular subnucleus, whereas most of the NS neurons were distributed in the dorsal part of the reticular subnucleus The conditioning stimulation in the central nucleus, basomedial and basolateral nuclei markedly inhibited the activities in 8 of 8 nociceptive neurons (3 WDR and 5 NS neurons) The inhibitory effect was 73 6±12 8% (mean±S.D) at maximum Naloxone (2mg/kg, iv.), opioid receptor antagonist, did not exert an influence on the amygdaloid inhibitory effect (n=4) The present results suggest that the amygdaloid nucleus inhibits the ascending nociceptive information at the 2nd order neurons through a receptor other than the opioid receptor. It has been known that the amygdaloid nucleus is a key structure for mediating stress responses Therefore, the amygdaloid antmociceptive effect may provide one of the neurophysiological bases for stress-induced analgesia (SIA), especially non-opioid type SIA.

We observed four fused teeth of the mandibular lateral incisor and the mandibular canine on three patients. In Case 1, both sides of the teeth were fused to the tooth crown and root. From observation of dental radiography, we were able to confirm that the fusion area of these teeth reached to the dentin. In Case 2, the tooth crown was divided into two parts, mesial and distal, and was fused to the tooth root. From observation of dental radiography, the fusion area of the tooth was confirmed to reach to the dentin. In Case 3, we were able to confirm from observation of plaster model that the tooth crown was fused completely. The appearance rate of fused permanent teeth was 0.3%. We thought that the abnormal cases appeared as a result of many embryological phenomena. We propose that the abnormal cases should be reported along with the detail data, and not thought to be rare.

本研究の目的は,各個人に適した歯列弓形態を考えるための基礎資料として,日本人成人における歯列と□蓋および頭蓋との関走既を明らかにすることである。矯正治療経験のない日本人成人男子168名(平均年齢25歳5か月)を対象に,歯列模型から歯列弓の幅径と長径,歯槽基底部の幅径と長径,□蓋の深さと容積,生体から頭長および頭幅を計測した.得られた計測値については, Pearsonの相関係数を算出し,さらに相関係数の検定を行って比較検討した。結果は以下の通りであった。1.上顎歯列弓長径と第一大臼歯部の歯列の幅か大きいほど,口蓋が深く,容積が大きい傾向が認められた。2.頭長が大きいほど,上顎第一大臼歯部の歯列の幅が大きい傾向が認められた。3.頭幅が大きいほど,上下顎第一大臼歯部の歯列の幅が大きい傾向が認められた。4.上顎前突は反対校合より頭長が大きい傾向が認められた。以上のことから,歯列は口蓋の形態および頭蓋の大きさと関連があることが示され,歯を排列する際には,歯と歯槽基底部の大きさの調和を考慮するだけでなく,頭蓋の大きさも考慮する必要性が示唆された, The purpose of this study was to elucidate the relation of dentition to the palate and the cranium in Japanese adults to serve as fundamental material for considering the morphology of dental arch well fitted to each person. In 168 Japanese male adults with no history of orthodontic treatment (mean age of 25 years and 5 months), the dental arch length and width, basal arch length and width, palate depth and volume as well as biometric head length and breadth were measured using a set of dental casts. From the determined values thus obtained, the correlative coefficient was calculated and tested for comparison. The results of this study reveal as follows : 1. The maxillary arch length and the width of inter-1 st molars tended to become larger with more deepened palate, indicating a tendency of larger volumes of the palate. 2. The larger the head length was, the larger the width of inter-maxillary 1 st molars became. 3. The larger the head breadth was, the larger the width of inter-1st molars of both arches became. 4. The maxillary protrusion tended to have a larger head length as compared with the mandibular protrusion. From the results mentioned above, the dentition was revealed to closely relate to the palate and the cranial size, and it was thus suggested that not only the harmonized size of the tooth and alveolar base but also the cranial size should be considered when the teeth are aligned.

歯科矯正治療についての知識や情報が一般的に知られ,歯の健康に対する意識や審美的意識の向上により,なかでも成人女性の矯正治療を希望する割合は年々増加する傾向にある。しかし,女性は40歳をさかいに骨密度が減少すると言われている。骨粗鬆症と歯槽骨の関係に関してはいくつかの報告があるが,歯の移動に関する報告はほとんどない。本研究では,12週齢の正常ラットと骨粗鬆症ラットの臼歯部に,矯正治療用ゴムリングを挿入し歯の移動を行った。歯槽骨の組織学的観察は一次抗体にTGF-β1抗体を用いた免疫組織染色法にて行った.その結果,骨粗鬆症であっても矯正力でTGF-β1は誘導され,歯槽骨骨梁の骨芽細胞ならびに破骨細胞に作用し,骨形成と骨吸収の両作用を活性化することにより歯槽骨の改造を引き起こすが,骨粗鬆症群では骨吸収の亢進と骨形成開始の遅延が生じている可能性が示唆された。, With recently prevailed knowledge and information on orthodontic treatment as well as improved awareness about dental health and aesthetic concerns, the proportion of adult female orthodontic patients has tended to increase yearly. The decreases of bone density in females forty and older are known. Although several reports have investigated the possible relationship between osteoporosis and the alveolar bone, we could not find a report concerning the tooth movement in relation to this disease. In this study, we confirmed that tooth movement was experimentally induced by inserting a gum ring for orthodontic treatment onto the molar site of normal and osteoporotic rats 12 weeks postpartum. The histological study of the alveolar bone was performed with immunohistological staining using TGF- β 1 antibody as a primary antibody. As a result, we found that TGF-β 1 is induced by orthodontic force and acts on osteoblasts and osteoclasts in the alveolar bone and ultimately induces a reconstruction of alveolar bone through activation of both bone formation and resorption. This also occurred even in the case of osteoporosis, however, an enhanced bone resorption and delayed initiation of bone formation was suggested in the osteoporotic group.

Though it has been reported that osteoblasts perceive extracellular calcium levels and regulate the differentiation and function of osteoclasts, the details of its mechanism of calcium perception or of its genetic expression system mostly remains unclear. In the present study, therefore, the influence of a high-calcium environment on osteoblasts was examined from the expressions of RANKL and CaSR mRNAs as well as from the formation of osteoclasts following cocultures. The identification of CaSR was made by the immunohistochemical staining method using rat alveolar bones with experimental tooth movement. On the third and seventh days after manipulation, both osteoclasts and osteoblasts showed CaSR positive reaction on the compressed side of the alveolar bones. On the other hand, CaSR positive reaction was observed only for osteoblasts on the tension side of the alveolar bones, though the reaction was weak. In the subsequent experiment using an osteoblast-like cell line (SaOS-2 ), PT-PCR was performed by changing the calcium concentration in the cultured solution from 1.8 to 2.5, 10 and 40 mM and further by treating with 0.1 and 1.0 μM of ionomycin. The PCR products of RANKL and CaSR mRNAs were then analyzed. The expressions of RANKL and CaSR mRNAs decreased in a calcium concentration dependent manner. When SaOS-2 cells were treated with ionomycin, RANKL mRNA expression increased in a dose dependent manner. However, CaSR mRNA expression increased at 0.1 μM ionomycin but showed almost no difference at 1.0 μM as compared with the untreated level. In order to examine the effect of calcium on the differentiation of osteoclasts, SaOS-2 cells were cocultured with a human myeloid leukemia cell line (HL-60). Total RNAs were extracted after SaOS- 2 cells pretreated with calcium were cocultured with HL-60 and after SaOS-2 cells pretreated with lα,25(OH)_2D_3 were cocultured with HL-60 under the presence of calcium, and the amount of tartrate-resistant acid phosphatase (TRAP) mRNA expression was examined by RT-PCR, Simultaneously, the number of osteoclasts that appeared was counted. As a result, the expression of TRAP mRNA increased in a dose dependent manner up to the calcium level of 2.5 mM but decreased at levels above it. The number of osteoclast-like cells showed a similar pattern to the expression of TRAP mRNA. In the case of SaOS-2 cells pretreated with 1α,25(OH)_2D_3, the TRAP mRNA expression increased in a dose dependent manner up to a calcium level of 10 mM but the expression at a calcium level of 40 mM decreased to a similar level observed at 1.8 mM. From the results mentioned above, it was suggested that a high extracellular calcium level in osteoblasts suppresses the expression of RANKL through CaSR which exists in the cell membrane and further suppresses the differentiation of osteoclastic precursors to osteoclasts.

During the tooth movement, an optimal compressive force (orthodontic force) must be applied to the periodontal ligament. In order to achieve an optimal force, it is important to understand the changes of blood flow and the vascular networks on the pressure side of the periodontal ligament. However, there are few published reports about the long-term daily changes of the blood flow in the vascular networks of the periodontal ligament. We studied the daily changes of the blood flow in the pressure side of the periodontal ligament of the dog mandibular canine using a microcirculation analyzer, which enables to discriminate between blood flow of arteries and veins based on a cross-correlation coefficient between laser speckle and pulse signals. We measured the blood flow in the pressure side of its periodontal ligament through a thin cavity wall. The following results were obtained ; 1. The microcirculation analyzer and the cross-correlation coefficient that we used in this study could measure the changes of arterial and venous blood flow on the pressure side of the periodontal ligament. 2. The overall blood flow after the force application decreased immediately. 3. The blood flow after the force application increased on day 1 especially in the arteries. 4. The arterial and venous blood flow recovered after 3, 7, and 14 days of the force application to the same levels as under non-pressurized conditions.

The effect of conditioning stimulation of the internal capsule (IC) on nociceptive neurons in the rat medullary dorsal horn was investigated The animals were anesthetized with N_2O-O_2 (2 1) and 0 5%-halothane, and immobilized with pancuronium bromide Nociceptive neurons responding to noxious stimulations of the face and oral structures were recorded in the trigemmal caudal nucleus and the medial reticular subnuclei These neurons were classified into wide dynamic range (WDR) and nociceptive-specific (NS) types NS neurons were distributed in the superficial layers of the caudal nucleus and the dorsal part of the reticular subnuclei, whereas WDR neurons were distributed diffusely throughout the area except for the magnocellular layer of the caudal nucleus A test stimulus with a single rectangular pulse (5-70 V) was applied to the center of the receptive field, the nociceptive neurons exhibited short-and/or long-latency responses Both responses in about 53% of the nociceptive neurons were inhibited by conditioning stimuli to the ipsilateral IC with trains of 33 pulses (100-300 μA) at 330Hz The percent of inhibitory effects on the WDR neurons and NS neurons were 20 7±245% (n=16) and 165±137% (n=2), respectively The inhibitory effect continued for conditioning-test intervals of up to 500 msec Effective sites for conditioning stimulation were concentrated in the lateral side of the IC, through which the corticofugal fibers from the somatosensory and motor cortices pass The IC inhibitory effect was not affected by a systemic injection of naloxone Our findings suggest that the transmission of nociceptive information is modulated at the level of the medullary dorsal horn by the corticofugal fiber via the IC and that transmitters other than opioids are involved in the IC antmociception

通常臨床歯科医学における骨移植は,その病理学的形態より3壁性骨欠損を有する歯周病患者に対して広く行われている。今回,下顎前歯部(下顎結合部)唇側面歯槽骨の開窓や限局性穿孔は存在するが,歯肉退縮を生じていない骨格型III級不正咬合患者へ顎矯正手術と同時に自家骨移植を付加的に行った。初診時のセファログラム所見より高く幅の狭い下顎結合部とこの薄い骨に直立している下顎前歯が確認された。また,術前矯正歯科治療中,下顎前歯はその捻転の解消と頬舌的な移動が行われた。手術時には下顎前歯部の開窓や限局性穿孔が確認された。下顎前歯部(下顎結合部)唇側面に自己海面骨を移植することによって歯槽骨の開窓や限局性穿孔は覆われた。結果的にセファログラム上での経過所見より,その後4年10か月間移植骨の残留が認められ,さらに臨床的に咬合が安定し通常後戻りしやすいとされる下顎前歯捻転の後戻りも認められず良好な結果を得たので報告した。, Bone graft in clinical dentistry prevails in periodontal patients who have three wall infrabony defect around the tooth because of its pathological morphology. In this case report, bone graft on the labial bone surface of the lower incisors (mandibular symphysis) was applied as an auxiliary procedure at the same time of orthognathic surgery to a patient who had fenestrations and circumscribed holes without gingival recession and skeletal Class III malocclusion. The initial lateral cephalometric radiograph revealed a narrow and high symphysis, with an incisor position straight above the thin bone. During the pre-surgical orthodontic treatment, the incisors had been derotated and moved in the minimal labiolingual direction. Some fenestrations and circumscribed holes were found during orthognathic surgery. Through the bone allograft, the labial bone surface of the lower incisors (mandibular symphysis) with fenestrations and circumscribed holes were covered with the patient's cancellous bone. Consequently, a series of the lateral cephalometric radiographs revealed that the grafted bone was kept for four years and ten months after surgery with stable occlusion and no rotational relapse on the lower incisors where it is usually easy to relapse clinically.

The route of lymphatic vessels from the periodontal ligament to the mandibular foramen was studied in five male SD rats. After the animals were killed with an overdose of anesthesia, the mandibles were fixed, decalcified and embedded in GMA resin. Serial sagittal sections were made, stained and observed in a photomicroscope. In addition, the route of the lymphatic vessels from the periodontal ligament to the mandibular canal was three-dimensionally reconstructed. The lymphatic vessels in the periodontal ligament ran together with veins passing along the wall of the alveolus. In the apex region and the alveolar canal, they were located close to veins running together with arteries and nerves. In the alveolar part of mandibular canal, the vessels ran together with veins passing along the upper wall of mandibular canal. In the mandibular canal within the ramus of mandible, they separated from the upper wall of the mandibular canal as veins increased in diameter. The part of the mandibular foramen of the mandibular canal, the lymphatic vessels ran between veins and arteries. We conclude that the pressure producing the lymphatic flow is generated by masticatory force and arterial pressure in the periodontal ligament, by arterial pressure in the alveolar part of the mandibular canal, and by arterial pressure and the muscular pump of the medial pterygoid muscle in the mandibular foramen of the mandibular canal. The mandibular canal within the ramus of mandible is supposed to be the transitional region between the inside and the outside of the mandibule.

In the present study, the effects of experimental separation of the lower incisor on memory function and the levels of brain neurotransmitters and related compounds were examined in mice at day 2, 7 and 14 after separation (0.5 or 1.0mm) treatment. The effects of the treatment on memory functions were tested by the multiple maze, T-maze and radial maze methods. The effects of the treatment on levels of neurotransmitter-related compounds in the hippocampus, cerebral cortex, striatum and hypothalamus were examined by high-performance liquid chromatography with an electrochemical detection system after the end of the each memory test. In mice, the experimental incisor separation induced dysfunction of all memory tested and increased the levels of 3-methoxy-1-hydroxyphenylglycol (MHPG), the main metabolite of the neurotransmitter noradrenaline, in all brain areas only on day 2 after treatment. These results suggest that incisor separation may inhibit the memory function of mice via activation of the central noradrenergic system.

Using photodensitometry for 47 patients who had congenitally missing permanent teeth, excluding for third molars, bone mineral content (BMC), determined via dental radiographs, was compared with a control group of 43 patients who have all their teeth. In addition, bone age was determined by hand-wrist radiographs using the TW 2 method, and the differences of skeletal maturation between both groups were evaluated. The results are as follows : 1. The average BMC was significantly lower in the group missing teeth than in the control group both for young males (aged 7-15 years old) and young females (aged 6-15 years old). 2. The BMC in the group of people missing more than three teeth was significantly lower than those in the groups of people missing one or two teeth. 3. Regarding the average BMC by the location of missing teeth : The maxillo-mandibular group had the lowest BMC, followed by the second lowest mandible group and finally the maxillary group. By type of missing teeth : The molar, which contained at least one molar and anterior-premolar teeth group, had the lowest BMC. Second lowest was the group missing premolar followed by the group missing anterior. 4. In the groups with missing teeth, bone age was lower by 0.97 years in young males compared to 1.18 years in young females. These results show delayed skeletal maturation. In conclusion, this study clearly indicates that compared to the control group BMC is lower, and skeletal maturity has a tendency to be delayed in children with missing teeth. These results can assist planning of orthodontic treatment to patients with congenitally missing teeth.

歯周炎に罹患した症例では歯間離開や上顎前歯部の突出を伴う場合が多く,その歯周治療に矯正処置が欠かせない。我々は矯正処置を必要とした歯周炎患者の2症例を報告する。第一症例は中等度歯周炎に罹患した症例であり,その歯間離開と過蓋咬合が,歯周外科処置後の矯正治療によって改善することが可能だった。第二症例は,初診時点で上下顎前歯部が高度歯周炎に罹患しているために保存困難と思われた症例である。しかし,歯周外科処置と歯の移動による前歯部交叉咬合の改善によって,約10年の長期にわたり保存可能だった。高度歯周炎に罹患し,矯正処置を必要とする歯は,歯周外科後に適切な矯正処置が施されれば,咬合関係を改善して長期にわたり保存することが可能であると思われた。, Periodontal therapy often requires orthodontic treatment in case of diastema and extreme maxillary protrusion associated with severe periodontitis. We report two periodontal cases with orthodontic treatment. Diastema and deep overbite of the first case with moderate periodontitis was improved by orthodontic therapy after periodontal surgery. At first examination, the second case with anterior crossbite seemed to be difficult to preserve the front teeth because of the severe periodontitis. But the crossbite tooth was improved by minor tooth movement after periodontal surgery, and was preserved for about ten years. The malposition of teeth even if with severe periodontitis seemed to improve the occlusion by appropriate orthodontic treatment after periodontal surgery, and to preserve the teeth for a long time.

Upper airway obstruction by the tongue occurs frequently in patients with obstructive sleep apnea syndrome (OSAS). Consequently, eliminating the collapse of the pharyngeal structures and reducing the air resistance in the cavity of pharynx could lead to the improvement of respiratory disturbance during sleep. This paper reports a clinical trial of the mandibular advancement device (MAD) for the conservative treatment of OSAS. In this case, the MAD moved the mandible to an anteroinferior position, and advanced the root of the tongue and the soft palate. In addition, middle and inferior airway space were remarkably increased. It appears that the reduction in the total number of apneic events and in the apnea-hypopnes index is attributed to the effect of the MAD on the oropharyngeal structures. Thus, the MAD may be an effective therapeutic alternative in patients with OSAS, and dentists could contribute to the manegement of OSAS patients.