[in Japanese]

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To understand various problems which exist in maxillary and dentoalveolar growth of cleft palate patients, it is necessary to analyze factors that influence their growth in addition to the conventional cephalometrics or dental cast analysis. Especially, scar tissue which results from mucoperiosteal denudation of palatal bone is considered to be the major factor of maxillary underdevelopment and dental arch deformity. Therefore, the information about scar tissue distribution on the palate is essential to diagnosis and prognosis in orthodontic treatment. However, there was no reliable method to evaluate the scar tissue area. To solve this problem, the laser doppler flowmeter has been applied in our clinic to differentiate scar tissue from normal palatal tissue based on the difference in circulatory conditions. The effectiveness and reliability of the method were described in the previous article. In this study, scar tissue distribution was analyzed by laser doppler flowmetry and its relation to maxillary growth and dental arch form was examined.
The results were as follows:
1. Scar tissue distribution was divided into four types according to their extent.
2. There was a close relationship between scar tissue distribution and maxillary dental arch form. The constriction of the dental arch became more severe as the scar tissue area was extended.
3. There was no correlation between scar tissue distribution and maxillary growth both in horizontal and vertical directions.
From the a bove results, it was considered that scar tissue formed on the surface of palatal bone directly inhibits maxillary dentoalveolar growth. It was suggested that maxillary growth in the horizontal and vertical directions could be influenced by surgical invasion or scar tissue at the posterior part of the maxilla.

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Tachimura et al. (1995) have suggestedt hat levator veli palatini m uscle (LVP) activity is increased in relation to flow rate of air emitted from the oral cavity into the nasal cavity through the velopharynx of postoperativec left palate patients wearing well-adapteds peech aid. However, it has not clarified whether or not nasal air flow is involved in the regulatory system of LVP activity of normal speakers. The purpose of this study was to clarify the effect in the non-cleft normal speakers and to test the hypothesis that nasal air flow is an important factor in the regulatory system of LVP activity of normal speakers.
Five non-clef tn ormal speakers were selected as experimentals ubject. s To introduce phonatory air to the nasal cavity during phonation, a hollow tube with an aperture (φ5 mm) on its side was devised and inserted through the nostril to the velopharynx. Smoothed electromyogram of LVP, oral air pressure and nasal air flow were recorded. Two experiments were performed: In the first (Condition-1), the inner cavity of the tube inserted into the velopharynx was occluded thereby avoiding nasal air emission and in the second (Condition-2), phonatory air was introduced to the nasal cavity by means of reopening the inner cavity of the tube. The subjects pronounced the /pu/ more than 20 times in each condition.
LVP activity in the condition of emergence of nasal air flow (Condition-2) was significantly greater than ( P <0.05; t-test) that in the condition of no introduction of air to the nasal cavity (Condition-1). Multiple regression analyses based on LVP activity as a criterion variable and oral air pressure and nasal air flow rate as explanatory variables revealed that nasal air flow may influence LVP activity more dominantly than oral air pressure. It was concluded that nasal air flow is involved in the regulatory system of LVP activity of normal speakers.

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A 16-year 4-month-old female, at the first visit to our department, with bimaxillary cleft lip and palate was treated by surgical orthodontics and was applied telescope denture at the final prosthodontic treatment.
At the a ge of 18 years 2 months, expansion of the maxillary collapse dental arch was started in presurgical orthodontic treatment by the multibracket system. In the 18-month treatment period, at the age of 19 years 8 months, mandibular sagittal splitting osteotomy, mentoplastics, and bone onlay of nasal bone were performed. In this period, lip reconstructive surgery was performed after postsurgical orthodontic treatment, and retention was started at the age of 20 years 6 months. Closure operation of the rest hole in the palate was performed at the age of 20 years 11 months. Inner crowns of the upper first molar to the first premolar were connected by bar attachments and an overdenture (telescope)denture) was applied over these inner crowns after 3 months. After these treatments, facial appearance was improved and occlusion was stabilized and the patient was very satisfied. However, due to severe dental caries, a large, complex denture had to be applied. It was considered that if early orthodontic treatment could have been carried out and the maxillary dental arch could have been expanded as easily as brushing teeth, severe caries might not have occurred and a more simple prosthodontic appliance could have been applied.

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The three-dimensional deformities of the premaxilla are often found in bilateral cleft lip and palate (BCLP) patients following primary repair. It is sometimes necessary to perform osteotomy of the premaxilla, because it is difficult to obtain satisfactory occlusion by orthodontic treatment to the floating premaxilla only, especially the indicated protrusion with an excessive deep bite, or reversed occlusion. Surgical repositioning the displaced premaxilla and simultaneous bone grafting into the alveolar cleft were performed on 9 BCLP patients from 1974 to 1995.
The results were as follows:
1. Good results were achieved, and all patients currently have acceptable results. The usefulness of this surgical procedure was confirmed, as follows:
1) The displaced premaxilla can be repaired th ree-dimensionally as assumed preoperatively by this surgical technique.
2) Since cross-linking of bone occurred in the alveolar cleft portion, orthodontic treatment of not only central incisors but also lateral teeth became easy after this surgical procedure. Therefore, the desirable occlusion can be obtained.
3) The residual oronasal fistula around the premaxilla can be closed simultaneously.
4) The preoperative esthetic deformity and oral functional disorder can be corrected.
2. It is important to have close cooperation between oral surgeon and orthodontist for obtaining long lasting good results.
3. This surgical procedure should be performed actively, because it is valuable and orthodontic treatment is proggressing.

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