車椅子利用下における路面の影響調査

【目的】車椅子利用者の安楽に及ぼす影響の１つとして「声かけ」に注目して，バリアが車椅子利用者の体感にどのような影響を及ぼすのかを知ることとを目的とした研究を行った． 【方法】対象者は，２０歳代女性の看護学生で，車椅子利用時の体感に体重が影響することを考慮し標準体重に近い者を選定した．路面の状態については，観察，自走介助兼用車椅子に装着した振動計，座席用振動ピックアップを用い客観的測定を行った．声かけによる路面の状態による主観的反応の相違は，対象者６０人を無作為にA群の「声かけあり群（n＝３０）」と，B群の「声かけなし群（n＝３０）」の２群に分けて把握した． 【倫理的配慮】対象者に本研究の目的及び方法を説明し，同意書に署名してもらった． 【分析方法】アンケート調査結果について２群を比較した．ゆれ・恐怖感・乗り心地の段階評価においてはウィルコクソンの符号順位和検定を行った． 【結果および考察】路面の見かけと振動値は概ね一致していたが，見かけは平らであっても振動値は高い場所もあった．路面に対する反応は以下の通りである． １．振動が大きいところでは対象者の全身に振動を与え，不快をもたらしていた． ２．傾斜があるところでは対象者に恐怖感をもたらしていた． ３．声かけは対象者が振動を予測して，態勢を整えることに役立っていた． ４．声かけは安心感や気分転換等にもつながっていた． 以上のことから，車椅子利用者の介助に当たって声かけをすることは重要であることが明らかになった．また，多様な路面の性状下でも快適な車椅子利用ができるような介助の方法を探究していきたい．さらに，今回の結果は，車椅子以外にもシルバーカーや自走車椅子利用者の支援のあり方を示唆するものと考えられる．Aim : A research was conducted to investigate the influence by barriers of road surface on the bodily sensation of wheelchair users, while paying attention to “calling” as a factor influencing the comfort of the users. Method : The subjects were chosen from student nurses in their twenties. The objective measurement of the conditions of road surface was carried out through the use of observation, a vibrograph equipped on wheelchairs designed for both self-propelling and attendant-propelling, and a vibration pickup set on the seat of the wheelchairs. In order to grasp the differences emerged from calling in the subjective responses to road surface conditions, the 60 subjects were divided randomly into 2 groups of A and B, the former was “the group with calling（n=30）” whereas the latter was “the group without calling（n=30）”. Ethical consideration : The subjects were explained about the aim and method of the research, and requested to sign the agreement of participation. Analysis method : A comparison between the two groups on the results of the questionnaire was carried out. For the stage assessment of the vibration, fear and feeling of using a wheelchair, the Wilcoxon signedrank test was performed. Results and Discussion : There was a general concordance between the appearance of the road surface and the vibration level, but there were some spots where the vibrational levels were high although the surface appeared to be flat. The followings were the responses to the road surface. 1. Where the vibration levels were high, shakes were caused to the subjects’ bodies and made them feel uncomfortable. 2. Besides vibration, slopes on the road also caused the feeling of fear to the subjects. 3. Calling helped the subjects to predict a vibration and to be ready for it. 4. Calling related to the feeling of relief and mood changes, as well. From those findings, it has been clarified that calling is essential in assisting a wheelchair user. Also, it is a future theme to search for a way to assist in a comfortable use of wheelchairs under various conditions of the road surface

車椅子利用下における路面の影響調査

【目的】車椅子利用者の安楽に及ぼす影響の１つとして「声かけ」に注目して，バリアが車椅子利用者の体感にどのような影響を及ぼすのかを知ることとを目的とした研究を行った． 【方法】対象者は，２０歳代女性の看護学生で，車椅子利用時の体感に体重が影響することを考慮し標準体重に近い者を選定した．路面の状態については，観察，自走介助兼用車椅子に装着した振動計，座席用振動ピックアップを用い客観的測定を行った．声かけによる路面の状態による主観的反応の相違は，対象者６０人を無作為にA群の「声かけあり群（n＝３０）」と，B群の「声かけなし群（n＝３０）」の２群に分けて把握した． 【倫理的配慮】対象者に本研究の目的及び方法を説明し，同意書に署名してもらった． 【分析方法】アンケート調査結果について２群を比較した．ゆれ・恐怖感・乗り心地の段階評価においてはウィルコクソンの符号順位和検定を行った． 【結果および考察】路面の見かけと振動値は概ね一致していたが，見かけは平らであっても振動値は高い場所もあった．路面に対する反応は以下の通りである． １．振動が大きいところでは対象者の全身に振動を与え，不快をもたらしていた． ２．傾斜があるところでは対象者に恐怖感をもたらしていた． ３．声かけは対象者が振動を予測して，態勢を整えることに役立っていた． ４．声かけは安心感や気分転換等にもつながっていた． 以上のことから，車椅子利用者の介助に当たって声かけをすることは重要であることが明らかになった．また，多様な路面の性状下でも快適な車椅子利用ができるような介助の方法を探究していきたい．さらに，今回の結果は，車椅子以外にもシルバーカーや自走車椅子利用者の支援のあり方を示唆するものと考えられる．Aim : A research was conducted to investigate the influence by barriers of road surface on the bodily sensation of wheelchair users, while paying attention to “calling” as a factor influencing the comfort of the users. Method : The subjects were chosen from student nurses in their twenties. The objective measurement of the conditions of road surface was carried out through the use of observation, a vibrograph equipped on wheelchairs designed for both self-propelling and attendant-propelling, and a vibration pickup set on the seat of the wheelchairs. In order to grasp the differences emerged from calling in the subjective responses to road surface conditions, the 60 subjects were divided randomly into 2 groups of A and B, the former was “the group with calling（n=30）” whereas the latter was “the group without calling（n=30）”. Ethical consideration : The subjects were explained about the aim and method of the research, and requested to sign the agreement of participation. Analysis method : A comparison between the two groups on the results of the questionnaire was carried out. For the stage assessment of the vibration, fear and feeling of using a wheelchair, the Wilcoxon signedrank test was performed. Results and Discussion : There was a general concordance between the appearance of the road surface and the vibration level, but there were some spots where the vibrational levels were high although the surface appeared to be flat. The followings were the responses to the road surface. 1. Where the vibration levels were high, shakes were caused to the subjects’ bodies and made them feel uncomfortable. 2. Besides vibration, slopes on the road also caused the feeling of fear to the subjects. 3. Calling helped the subjects to predict a vibration and to be ready for it. 4. Calling related to the feeling of relief and mood changes, as well. From those findings, it has been clarified that calling is essential in assisting a wheelchair user. Also, it is a future theme to search for a way to assist in a comfortable use of wheelchairs under various conditions of the road surface

Relationships between nasal resistance, adenoids, tonsils, and tongue posture and maxillofacial form in Class II and Class III children

Introduction: The purpose of this study was to clarify the relationships between upper airway factors (nasal resistance, adenoids, tonsils and tongue posture) and maxillofacial form in Class II and III children Methods: Sixty-four subjects (mean age, 9.3 years) with malocclusion were divided into Class II and Class III groups by ANB angle. Nasal resistance was calculated using computational fluid dynamics from cone-beam computed tomography (CBCT) data. Adenoids, tonsils and tongue posture were evaluated in CBCT images. The groups were compared using Mann-Whitney U-tests and Student t-tests. Spearman’s rank test assessed the relationships between upper airway factors and maxillofacial form. Results: Nasal resistance of the Class II group was significantly larger than that of the Class III group (P = 0.005). Nasal resistance of the Class II group was significantly correlated with inferior tongue posture (P < 0.001), and negatively correlated with intermolar width (P = 0.028). Tonsil size of the Class III group was significantly correlated with anterior tongue posture (P < 0.001) and mandibular incisor anterior position (P = 0.007). Anterior tongue posture of the Class III group was significantly correlated with mandibular protrusion. Conclusions: The relationships of upper airway factors differed between Class II and Class III children

Upper airway evaluation of children with unilateral cleft lip and palate using computational fluid dynamics

Introduction: Children with unilateral cleft lip and palate (UCLP) exhibit snoring and mouth breathing. They are also reported to show obstructive sleep apnea syndrome. However, their upper airway ventilation condition is not clearly understood. Therefore, this study was performed to evaluate upper airway ventilation condition in children with UCLP with the use of computational fluid dynamics. Methods: Twenty-one children (12 boys, 9 girls; mean age 9.1 years) with UCLP and 25 children (13 boys, 12 girls; mean age 9.2 years) without UCLP who required orthodontic treatment underwent cone-beam computed tomography (CBCT). Nasal resistance and upper airway ventilation condition were evaluated with the use of computational fluid dynamics from CBCT data. The groups were compared with the use of Mann-Whitney U tests and Student t tests. Results: Nasal resistance of the UCLP group (0.97 Pa/cm3/s) was significantly higher than that of the control group (0.26 Pa/cm3/s; P < 0.001). Maximal pressure of the upper airway (335.02 Pa) was significantly higher in the UCLP group than in the control group (67.57 Pa; P < 0.001). Pharyngeal airway (from choanae to base of epiglottis) pressure in the UCLP group (140.46 Pa) was significantly higher than in the control group (15.92 Pa; P < 0.02). Conclusions: Upper airway obstruction in children with UCLP resulted from both nasal and pharyngeal airway effects

HERBST EFFECTS ON PHARYNGEAL AIRWAY VENTILATION

Objective: To evaluate the effect of a Herbst appliance on ventilation of the pharyngeal airway (PA) using computational fluid dynamics (CFD). Materials and Methods: Twenty-one Class II patients (10 boys; mean age, 11.7 years) who required Herbst therapy with edgewise treatment underwent cone-beam computed tomography (CBCT) before and after treatment. Nineteen Class I control patients (8 boys; mean age, 11.9 years) received edgewise treatment alone. The pressure and velocity of the PA were compared between the groups using CFD based on three-dimensional CBCT images of the PA. Results: The change in oropharyngeal airway velocity in the Herbst group (1.95 m/s) was significantly larger than that in the control group (0.67 m/s). Similarly, the decrease in laryngopharyngeal airway velocity in the Herbst group (1.37 m/s) was significantly larger than that in the control group (0.57 m/s). Conclusion: The Herbst appliance improves ventilation of the oropharyngeal and laryngopharyngeal airways. These results may provide a useful assessment of obstructive sleep apnea treatment during growth

Determination of midsagittal plane for evaluation of facial asymmetry using three-dimensional computed tomography

Purpose: The aim of the present study was to investigate the disagreement of cephalometric analysis depending on the reference determination of midsagittal plane on three-dimensional computed tomography. Materials and Methods: A total of 102 young women with class III dentofacial deformity were evaluated using three-dimensional computed tomography. The cranial and facial midsagittal planes were defined and the amounts of jaw deviation were calculated. The amounts of jaw deviation were compared with paired t-test (2-tailed) and Bland-Altman plot was drawn. Results: The landmark tracing were reproducible (r??978). The jaws relative to the cranial midsagittal plane were 10-17 times more significantly deviated than to the facial midsagittal plane (P??001). Bland-Altman plot demonstrated that the differences between the amounts of jaw deviation from two midsagittal planes were not normally distributed versus the average of the amounts of jaw deviation from two midsagittal planes. Conclusion: The cephalometric analyses of facial asymmetry were significantly inconsistent depending on the reference determination of midsagittal plane. The reference for midsagittal plane should be carefully determined in three-dimensional cephalometric analysis of facial asymmetry of patients with class III dentofacial deformity. ⓒ 2011 by Korean Academy of Oral and Maxillofacial Radiology.

Stress distribution patterns at mini-implant site during retraction and intrusion - a three-dimensional finite element study

Abstract Background The purpose of this study was to evaluate the stress patterns produced in mini-implant and alveolar bone, for various implant dimensions, under different directions of simulated orthodontic force, using a three-dimensional finite element method. Methods Eight finite element (FE) models of mini-implant and bone were generated with insertion angles of 30° and 60°, diameters of 1 and 1.3 mm, and lengths of 6 and 8 mm. A simulated constant orthodontic force of 2 N was applied to each of these FE models in three directions simulating anterior retraction, anterior intrusion and retraction, and molar intrusion. Results Comparison of the maximum von Mises stress in the mini-implant showed that the 1-mm diameter produced significantly high stress, and the amount of stress produced was more for a mini-implant inserted at an angle of 60°. The cortical bone showed that high stresses were generated for the 1-mm-diameter mini-implant and on increasing the insertion angulation from 30° to 60°, the stress produced increased as well. The comparison of von Mises stress in the cancellous bone was insignificant as the amount of stress transmitted was very low. Conclusions The 1-mm-diameter mini-implants are not safe to be used clinically for orthodontic anchorage. The 1.3 × 6 mm dimension mini-implants are recommended for use during anterior segment retraction and during simultaneous intrusion and retraction, and the 1.3 × 8 mm dimension mini-implant is recommended for use during molar intrusion. All mini-implants should be inserted at a 30° angle into the bone for reduced stress and improved stability

Reliability and accuracy of a radiographic analysis method for posterior maxillary mini-implant location

OBJECTIVE: The purpose of this study was to evaluate the reliability and accuracy of a radiographic analysis method for the location of mini-implants inserted in the posterior region of the maxilla. MATERIAL AND METHODS: Two self-drilling mini-implants were installed between the second premolar and the first molar on the right side and left side in three dry skulls. Three operators performed three occlusal radiographs, using an occlusal x-ray film holder, at three different times in each of the three skulls. RESULTS: The interclass correlation coefficient showed a significantly high, positive correlation (p<0.05), indicating an excellent reliability between operators. The analysis of variance showed no significant differences in time and among the operators. CONCLUSION: Based of these findings, it may be concluded that this methodology can be used by several operators in longitudinal clinical studies on orthodontic mini-implants at the anterior-posterior and lateral-medial locations or longitudinal displacement