Toshiya Kuwahara

The influence of postoperative treatment on the results of TMJ meniscectomy. Part II: comparison of chewing movement.

In order to evaluate the influence of different types of postoperative treatments on the results of TMJ surgery, chewing movement recorded postoperatively was compared in 32 patients with unilateral total meniscectomy, 42 patients with partial meniscectomy with disk repair, and 10 normal subjects. Postoperative treatment was of three different types depending on its strategy. It was found that postoperative treatment had a significant positive effect on the results of both total and partial meniscectomy. Postoperative treatment which included both physical medicine modalities and dental treatment demonstrated better results than only dental treatment or no postoperative treatment. However, none of these studied techniques could recover chewing movement to the normal range.

Clinical Study on the Effect of the Single Crown on Segmental Chewing.

Chewing is closely related to occlusion, and occlusion of a specific tooth affects segmental chewing. Therefore, analysis of chewing is supposed to have diagnostic value for assessing occlusion. However, the difference in segmental chewing among various teeth is unclear. Comparison in segmental chewing between before restoration and after restoration was performed in 55 patients who were treated by a single premolar or molar restoration.The results are summarized as follows:1. Chewing pattern and chewing speed pattern1) Premolar restoration had little effect on chewing.2) First molar restoration revealed a tendency to improve chewing, and second molar restoration demonstrated a tendency to worsen it.2. Chewing rhythmMolar restoration showed a tendency to shorten the duration of the occlusal phase.

The Relationship between Signs and Symptoms of Craniomandibular Disorders and MRI Findings.

Abnormalities of soft tissue of TMJ components are common in craniomandibular disorders. For the diagnosis of these abnormalities, MR imaging technique is useful. However, the relationship between MRI findings and signs and symptoms of craniomandibular disorders remains unclear.In this study, MRI findings and signs and symptoms of craniomandibular disorders were compared for 150 patients (300 TMJs) with craniomandibular disorders.

Effect of Abnormal Occlusion on Mandibular Movements during Speech

歯科医療の目的は、正常な顎口腔機能の回復 と維持であ り、その対象とな る顎 口腔機能 には 咀嚼、発語、嚥下等、多 くの ものがある1)。 咀 嚼に関 しては、従来 より詳細に研究 されてきた 2).3)が 、発語に関 しては、未だ不明な点が多 い。そのため、 日常臨床 において補綴処置たと えば前歯部ブ リッジや義歯 によって咀嚼障害の みならず発語障害を も訴える症例 に遭遇するこ とも少なくない。 発語は顎口腔系を構成す る種 々の器官の協調 によって営まれ るものであり、顎 口腔系諸器官 の異常が、発語における下顎運動に反映されて いるもの と考え られ る4キロ従 って、顎 口腔系を 構成する要素のひとつ である咬合は発語におけ る下顎運動に影響を与えていると考えている。 従来 より、補綴領域の発語に関する研究は単 音を対象 とした ものが多 く、義歯作製時におけ る咬合高径と関係につ いて論 じたものがある5). 6),7) 。 しか しなが ら、単音の発語は日常頻繁 に行われ る生理的なものではな く、また発語す る単音の種類 によって下顎位が異なること8)、 ある特定の単音で も前後の音が異なると発語時 の下顎位が異な ること9)、 さらに単音発語時の 下顎位は一定位置に静止 した ものではないこと 10)が 知 。また単音発語時はほぼ閉 口状態か ら始 まるのに対 し、連続音では先行す る音の開 口度 に影響 されることが予想 され る。 このことか ら、我 々は発語を生理的運動と して とらえる場合、連続音の発語における下顎運動 を検討す る必要があると考えてい る。 そこで本研究においては、発語における下顎 運動に咬合異常が及ぼす影響を明らかにするこ とを目的とし、まず各種不正咬合を有する被験 者の発語時の下顎運動を検討 し、さらに咬合異 常の一つ と して個性正常咬合者の矢状切歯路角 を実験的に急傾斜にす ることにより、発語時の 下顎運動が どのように変化す るかについて検討 を加えた。

Effect of Malocclusion on Mandibular Movements during Speech.

To investigate the effect of malocclusion on mandibular movement during speech, the Sirognathograph Analyzing System was used to analyze the form of the envelope of motion during speech, as well as the relationship between the envelope of motion and eccentric movement paths, in 10 normal subjects and 60 subjects having malocclusion. Location of the envelope of motion, and the relationship between the envelope of motion and eccentric movement paths, were closely related to specific malocclusions. It is suggested that analysis of the envelope of motion during speech has diagnostic value in speech function assessment and that its detailed analysis offers valuable information for diagnosis and initiation of dental treatment.

Effect of Change in Occlusal Vertical Dimension on Chewing Movements. Part 1. Influences on the Rhythm of Chewing Movements.

Assessment of occlusal vertical dimension (OVD) is an essential in the dental treatment. However, physiolosical effects of the change in OVD remains unclear.The purpose of this study is to assess the effect of the change in OVD on the stomatognathic function by analyzing any chewing movements.Five subjects without any signs or symptoms of craniomandibular disorders and with normal occlusion (age: 24-28 years, 4 males and 1 female) were selected. Onlay-type appliance was fabricated to raise the OVD by about 2mm. The chewing movements were recorded and analyzed using the Sirognathograph Analyzing System III.As a result, no change was observed in cycle time of the chewing movements, however as for each duration, some changes was observed.

Diagnosis of stomatognathic function and dysfunction

Introduction Occlusion, masticatory muscles, and temporomandibula r joint (TMJ), together with the central nervous system, are integrated into the functional occlusion system, which plays an important role in the physiology of the stomatognathic system I). Abnormality in one of the three factors of the functional occlusion system causes disharmony of the system and is considered to be the most s ignif icant e t io logica l f a c t o r in the s tomatognathic dysfunction. There fore , exact diagnosis of the condition of the each factor is essential for the diagosis and treatment of stomatognathic dysfunction. P a t h o l o g y of the T M J is the stomatognathic dysfunction has not been clearly understood in the past. One of the reasons would have been lack of methodology to e v a l u a t e the T M J in the stomatognathic dysfunction in the clinical practice. But it is extremely important and significant to know and evaluate the information on the TMJ. Recently, TMJ radiography, which is one of the most effective methods for TMJ examination, has been developed to a stage that discrimination has been possible and the diagnosis of arthrogeneous TMJ dysfunction have been relatively easy and reliable. This article will summarize the results of our series of rediographic investigations 2-4) using simultaneous multilayer polytomography (polytom U, Philips Co.), which is one of the most available methods for the diagnosis of the arthrogenous TMJ dysfunction.Introduction Occlusion, masticatory muscles, and temporomandibula r joint (TMJ), together with the central nervous system, are integrated into the functional occlusion system, which plays an important role in the physiology of the stomatognathic system I). Abnormality in one of the three factors of the functional occlusion system causes disharmony of the system and is considered to be the most s ignif icant e t io logica l f a c t o r in the s tomatognathic dysfunction. There fore , exact diagnosis of the condition of the each factor is essential for the diagosis and treatment of stomatognathic dysfunction. P a t h o l o g y of the T M J is the stomatognathic dysfunction has not been clearly understood in the past. One of the reasons would have been lack of methodology to e v a l u a t e the T M J in the stomatognathic dysfunction in the clinical practice. But it is extremely important and significant to know and evaluate the information on the TMJ. Recently, TMJ radiography, which is one of the most effective methods for TMJ examination, has been developed to a stage that discrimination has been possible and the diagnosis of arthrogeneous TMJ dysfunction have been relatively easy and reliable. This article will summarize the results of our series of rediographic investigations 2-4) using simultaneous multilayer polytomography (polytom U, Philips Co.), which is one of the most available methods for the diagnosis of the arthrogenous TMJ dysfunction.