Bone graft on the labial symphysis for the skeletal Class III case

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\u27s 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

Effects of tooth movement on the alveolar bone in osteoporotic rats

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

下顎枝矢状分割術における生体内吸収性ポリ-L-乳酸骨接合ミニプレート固定の術後安定性について

左右非対称のない下顎前突症患者に対する下顎枝矢状分割術において,ポリ-L-乳酸製(PLLA)ミニプレート固定法による術後の顎態の安定性について検討を行った.両側下顎枝矢状分割術(SSRO)を施行し,下顎骨の後退量に左右差のない患者40名(男性17名,女性23名)を対象とした.これらの骨固定に際し,PLLAミニプレートを使用した患者22名(男性9名,女性13名)をPLLAプレート群とし,チタンミニプレートを使用した患者18名(男性8名,女性10名)をチタンプレート群とした.手術直前,手術後1か月,手術後1年に撮影した側面頭部X線規格写真の分析を行い,顎態の安定性について検討した.その結果,手術後1年ではPLLAプレート群およびチタンプレート群両群の男女ともに著しい後戻り様変化は認めなかった.このことから,SSROを用いた左右差のない下顎後退術に対するPLLAミニプレート固定は,術後顎態の安定性の観点からはチタンミニプレート固定と比較して何ら問題点はなく,プレートの除去手術が回避できる点で有益であると考えられる.アレルギーの有無や,顎骨の移動量等を総合的に判断し,PLLAミニプレートかチタンミニプレートを選択することができると考えられる.We studied the postsurgical stability of the mandible using biodegradable Poly-L-lactide bone mini plate fixation undergone sagittal split ramus osteotomy. The forty patients with mandibular prognathism without facial asymmetry (17 males and 23 females) operated from March 2003 to March 2009, were divided into two groups based on the types of osteosynthesis used. 22 patients (9 males and 13 females) using the PLLA mini-plate (PLLA plate group), and 18 patients (8 males and 10 females) using the titanium mini-plate (titanium plate group) were examined. Lateral cephalograms were taken immediately before the surgery, one month, and one year after surgery. Changes in position of the mandible were examined. As a result of this study, remarkable relapses were not recognized at one year after operation for males and females in both groups. It is thought the PLLA mini-plate fixation to the mandible without facial asymmetry setback doesn\u27t present as many problems from the viewpoint of postsurgical stability compared with the titanium mini-plate fixation, and it is profitable that we avoided the plate removal operation. We can select the PLLA or the titanium mini-plate from a comprehensive standpoint

矯正歯科治療における顔面三次元シミュレーション

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

歯胚位置異常の上顎犬歯を移転排列した骨格性反対咬合症例

初診時年齢9歳0か月の女児で,埋伏した上顎右側中切歯と位置異常の犬歯を伴った骨格性III級の一症例を報告する.埋伏した中切歯は逆生で歯根が屈曲していた.中切歯を抜去後,犬歯は抜去した中切歯の位置に自然に移動したが萌出は認められなかったため,上顎歯列にNanceのホールディングアーチを装着し犬歯の牽引を開始した.上顎犬歯はマルチブラケット装置を使用して十分なスペースを獲得した後,中切歯の位置に排列した.骨格性III級に対しては,上顎前方牽引装置を適用し顎間関係の改善を行った.マルチブラケットによる治療期間は,犬歯のスペース獲得のために11か月,牽引のために1年4か月,下顎を含めた全顎的な歯の排列のために2年11か月を要した.中切歯部に排列された犬歯は機能的にも問題はなく,形態修正を施すことにより審美的回復を得ることができた.This case report describes the orthodontic treatment of a 9-year-old girl with skeletal Cl III malocclusion, an impacted maxillary right central incisor, and ipsilaterally displaced canine. The impacted maxillary central incisor was inverted and the root was crooked. After the maxillary right central incisor was extracted, the ipsilateral canine spontaneously moved toward the extracted incisor position. However, eruption did not occur, so we began the traction of the maxillary right canine after setting Nance\u27s holding arch appliance for reinforced anchorage. The maxillary right canine was aligned the position of a central incisor after creating sufficient space using a multibracket appliance. For the skeletal problems, a maxillary protractive appliance was applied to improve the intermaxillary relationship. The treatment period employing the multibracket appliance was: 11 months for acquiring the canine space, one year and four months for traction of the canine, and two years and 11 months for full alignment of the maxillary and mandibular teeth, with a total of 5 years and 2 months. As a result, satisfactory dental aesthetics were achieved by adjusting the shape of the crown of the canine as well as realizing stable occlusion with a sufficient function