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Purpose The purpose of this study was to examine the relationship between occlusal force and condylar morphology in class II and III after sagittal split ramus osteotomy (SSRO) with Le Fort I osteotomy. Materials and methods The subjects were 42 female patients who underwent bi-maxillary surgery, and were divided into 2 groups (21 class II and 21 class III cases). They were selected randomly from among patients that underwent surgery from 2012 to 2017. Condylar height, ramus height, ramus inclination and condylar square were assessed by computed tomography (CT), preoperatively and 1 year postoperatively. Occlusal contact area and occlusal force were measured pre- and 1, 3, 6 and 12 months post-operative. Results Condylar height and ramus height of the class II advancement cases decrease more significantly than those of class III. There were no significant differences in time-course changes of occlusal force and area between the class II and III. In the class II cases, occlusal force at 1 and 3 months was significantly lower than the preoperative value (P = 0.0009, P = 0.0002). On the other hand, in class III, occlusal force at 1, 3 and 6 months (P = 0.0038, P = 0.0031, P = 0.0283) was significantly lower than the preoperative value. Conclusion This study suggested that occlusal force of the class II advancement cases reached the pre-operative level earlier than that of the class III setback cases, even though condylar height decreased after surgery in the class II cases. However, a correlation between occlusal force change and condylar height reduction after surgery could not be found.

The purpose of this study was to compare mandibular bone healing after advancement or setback surgery using sagittal split ramus osteotomy (SSRO).and Methods. The subjects were 50 patients (100 sides) who underwent bi-maxillary surgery, and were divided into 2 groups (25 class II advancement cases and 25 class III setback cases). They were selected randomly from the patients who underwent surgery between 2012 and 2017. Ramus square, ramus length and ramus width were measured in the horizontal plane image of computed tomography (CT), before and immediately after the operation, and at 1 year after the operation.Ramus square in the class III cases significantly increased in 1 year after the operation (P 0.0001), meanwhile there was no change after 1 year in the class II cases. Before the operation, there were no significant differences in the all measurements between classes II and III. However, for ramus width, class III was significantly larger than class II immediately after (P = 0.0014) and at 1 year after the operation (P = 0.0003).This study suggested that post-operative change in ramus morphology was different between class II advancement surgery and class III setback surgery.

The purpose of this study was to evaluate the relationship between computed tomography (CT) values of the condylar surface and temporomandibular joint (TMJ) disc position in the sagittal plane before and after sagittal split ramus osteotomy (SSRO) setback surgery, retrospectively. The subjects were 75 patients (150 condyles) who underwent bilateral SSRO setback surgery. They were divided into two groups (42 symmetric patients and 33 asymmetric patients). Maximum CT values (pixel values) of five points of the condylar surface and condylar height, length, fossa height, fossa length, and ramus angle in the sagittal plane were measured preoperatively and 1 year postoperatively. Disc position was classified as anterior disc displacement, anterior type, fully covered type, and posterior type, both pre- and postoperatively, using magnetic resonance imaging (MRI). Postoperative value was significantly higher than preoperative one in CT value of 135° (P = 0.0199) and 180° (0.0363), in the non-deviation side in the asymmetry group. The anterior disc displacement group was significantly larger than those of some other areas pre- and postoperatively in the CT value of 0° point (P

Purpose The purpose of this study was to compare time-course changes in temporomandibular joint (TMJ) space between mandibular advancement surgery and setback surgery after sagittal split ramus osteotomy (SSRO) and Le Fort I osteotomy. Subjects and Methods The subjects were 46 patients (92 joints) who underwent bi-maxillary surgery. The TMJ disc position was assessed by magnetic resonance imaging (MRI) and the anterior, superior, posterior, medial and lateral joint spaces were assessed by computed tomography (CT), preoperatively and at 1 week and 1 year postoperative. The 92 joints were divided into 2 groups, namely class II (n = 46 joints), and class III (n = 46 joints) (an advanced group vs a setback group). Next, the 92 joints were divided into 2 groups comprising 36 joints with anterior disc displacement joint (ADD group) and 56 joints without (non-ADD group). Time-course changes in the measurements were compared statistically between the advanced and setback groups, and between the ADD and non-ADD groups. Results There were no significant differences between the advance group and setback group regarding time-course change in all the joint spaces. However, there were significant differences between the ADD group and non-ADD group regarding time-course change in the medial, anterior, superior and posterior joint spaces (P Conclusion This study suggested that ADD could affect the time-course change in TMJ space and condylar position after bi-maxillary osteotomy.

The purpose of this study was to compare changes in temporomandibular joint (TMJ) and ramus morphology between class II and III cases before and after sagittal split ramus osteotomy (SSRO) and Le Fort I osteotomy.The subjects were 39 patients (78 sides) who underwent bi-maxillary surgery. They consisted of 2 groups (18 class II cases and 21 class III cases), and were selected randomly from among patients who underwent surgery between 2012 and 2016. The TMJ disc tissue and joint effusion were assessed by magnetic resonance imaging (MRI) and the TMJ space, condylar height, ramus height, ramus inclination and condylar square were assessed by computed tomography (CT), pre- and post-operatively.The number of joints with anterior disc displacement in class II was significantly higher than that in class III (p 0.0001). However, there were no significant differences between the two classes regarding ratio of joint symptoms and ratio of joint effusion pre- and post-operatively. Class II was significantly better than class III regarding reduction ratio of condylar height (p 0.0001) and square (p = 0.0005).The study findings suggest that condylar morphology could change in both class II and III after bi-maxillary surgery. The findings of the numerical analysis also demonstrated that reduction of condylar volume occurred frequently in class II, although TMJ disc position classification did not change significantly, as previously reported.

The purpose of this study was to examine the skeletal stability of mandibular advancement after sagittal split ramus osteotomy (SSRO) with modified hybrid fixation using absorbable plates and screws.A total of 54 Japanese patients were enrolled in this study. Of them, 23 who were diagnosed with mandibular prognathism underwent setback surgery with bi-cortical plate fixation using absorbable plates and screws (setback group). Another 23 who were diagnosed with mandibular retrognathism underwent advancement surgery with modified hybrid fixation using absorbable plates (advance group), and 8 who were diagnosed with mandibular retrognathism underwent advancement surgery with titanium plates (titanium group). Skeletal stability and horizontal condylar angle were analyzed by axial, frontal, and lateral cephalograms preoperatively and at 1 month, 3 months and 1 year post-operatively. The findings were compared statistically.The advance group showed no significant difference compared with the titanium group. There were significant differences between the setback and advance groups regarding SNB, ANB, gonial angle, ramus inclination, occlusal plane, convexity and Me-Ag right in T1 naturally (P 0.05). However, in T2, there were no significant differences between the groups for the other measurements, although there were significant differences in ANB, interincisal angle, occlusal plane and Me-Ag right (P 0.05). In T3, a significant difference was seen only in Me-Ag right (P = 0.0145).This study suggested that the use of an absorbable plate and screw was useful and reliable for mandibular advancement surgery as well as mandibular setback surgery, when the fixation method was devised successfully.

Purpose The purpose of this study was to examine lip closing force in Class II and III patients before and after orthognathic surgery. Subject and methods The subjects were 45 patients (15 Class II women, 15 Class III men and 15 Class III women) diagnosed with jaw deformity who underwent sagittal split ramus osteotomy with Le Fort I osteotomy and 30 controls with normal skeleton and occlusion (15 men, 15 women). Maximum and minimum lip closing forces were measured using Lip De Cum® before and after surgery, and compared statistically. Results In the Class II women, maximum and minimum lip closing forces did not change after surgery. However, maximum and minimum lip pressure increased significantly in the Class III men (P = 0.0116, P = 0.0295) and maximum lip closing force increased significantly in the Class III women (P = 0.0082). After 6 months, maximum lip closing force was significantly lower in both Classes II and III women than in the control women (P = 0.0002, P = 0.0045). Conclusions This study suggested that maximum postoperative lip pressure did not improve in the Class II women, although maximum lip closing force increased in the Class III men and women after sagittal split ramus osteotomy with Le Fort I osteotomy.

The purpose of this study was to evaluate maxillary sinus and predict the factors affecting the postoperative sinus condition after Le Fort I osteotomy using various fixation materials.The study subjects consisted of 71 patients (21 male and 50 female, 142 sides) who underwent Le Fort I osteotomy with sagittal split ramus osteotomy. The maxillary sinus bony area and the inside air area were measured in the coronal plane across the mesial aspect of the first molar perpendicular to the Frankfurt horizontal plane of a computed tomography (CT) image preoperatively and at 1 week and 1 year after surgery. The rate of intact sinus area (the inside air area/the maxillary sinus bony area) was calculated. Subjects were divided into groups according to gender, preoperative diagnosis (Angle class II and III with and without asymmetry), plate fixation material (PLLA and uHA/PLLA), and use or non-use of bone alternative material (α-tricalcium phosphate). Statistic comparisons between groups were performed in each division. Furthermore, age, operation time, amount of blood loss, and direction and amount of movement were examined as the continuous variables to statistically predict the rate of intact sinus area after 1 week and 1 year.The rate of intact sinus area after 1 week was significantly correlated with age, amount of anterio-posterior movement, and preoperative rate of the intact sinus area (p 0.0001). Rate of intact sinus area after 1 year was significantly low in the group that used the bone alternative material compared to the group that did not (p 0.0282).The study suggests that the bone alternative material might be a cause of inflammation in the sinus after 1 year. Moreover, attention needs to be paid to older age, backward movement of the maxillary segment, and preoperative sinusitis including hypertrophy of sinus membrane in Le Fort I osteotomy.

Purpose The purpose of this study was to evaluate the effect of bone regeneration enhancement by ultra-violet (UV) treatment of an unsintered hydroxyapatite (u-HA)/poly- l -lactic acid (PLLA) mesh in rabbitnasal bone. Materials and methods Thirty adult male Japanese white rabbits (12–16 weeks, 2.5–3.0 kg) were used in this study. After incising along the nasal bone, 6 × 6 × depth 1 mm two bone defects were made on both sides. In the UV group (n = 30), the defects were covered with uHA/PLLA mesh, treated by UV (wavelength 172 nm, tube wall illumination 13 mW/cm 2 , period 8 min, intensity 6.26 J/cm 2 ) and screwed. In the control group (n = 30), untreated uHA/PLLA was applied in a similar manner. The rabbits were sacrificed at 1, 2, 3, 4 and 6 weeks postoperatively, and formalin-fixed specimens were frozen. The specimens were stained with haematoxylin and eosin. For immunohistochemical analysis, the specimens were treated with anti-alkaline phosphatase (ALP). Finally, bone ratio and ALP expression were evaluated microscopically. Results The UV group had a significantly higher number of ALP stained cells than the control group after 1, 2, and 3 weeks (P Conclusion This study suggests that bone regeneration can be enhanced by UV treatment using an uHA/PLLA mesh.

Summary 1 With and without electrical pulses, the action of mescaline on respiration of preparations of rat cerebral cortex in the presence of glucose was determined. 2 When electrical pulses were applied to the tissue of control, its respiration value increased about 1.6 times higher than that of the original value. But after the pulses were removed the value was restored to that of the resting state. 3 The respiration of tissue without electrical pulses was slightly inhibited at the concentration of 1O-2 M of mescaline, but did not show any effect at the concentrations of 3 × 10-3 M and 10-4 M, either. 4 Unexpectedly, there was no inhibition of extra uptake of oxygen of the tissue under the electrical pulses, even at the concentration as high as 10-2 M of mescaline. 5 After the pulses were removed, at the concentration of 10-3 M, 3 × 10-3 M, 10-2 M mescaline could inhibit the respiration to 22.7, 33.8 and 50.0 per cent respectively, compared with the control. 6 From these observations, it was suggested that some enzymes, which might act only on the resting state, might be disturbed by mescalin under coopzration in of stimulation of electrical pulses on the cerebral tissue.

Summary In order to investigate the influence of Antihistaminica (AH) upon ISD, experiments were made in ten series upon seven subject.;, where each subject received 25 r of LSD orally and afterward 15–45 mg. of AH interavenously in slow injection. The results obtained are as follows: In all cases, accentuation of the LSD symptoms took place; in two cases of 15 mg. AH. accentuation stayed slight, the duration short and the effect insufficient, contrasted with seven cases of 30 mg. AH with conspicuous accentuation with duration over 80 minutes in average. The said dose must be appropriate for the purpose. And in another case administered with 45 mg., there appeared findings speaking for an over-dose, it is well assumable that AH effect is expressed always proportionate to its dose. AH effect is manifested most remarkably in the acme of the LSD symptoms; that effect gets rapidly weakened with decrease of the action of LSD speaking in itself that AH works intensifying the LSD action but little prolonging the course of the action. In a control case administered with AH alone, it was found that the symptoms of accentuation above mentioned bear in within such symptoms proper to AH, itself constituting portion of AH effect in question. It is clear that the accentuation is a thing of higher order than sheer summation of symptoms of both drugs. As a side-proof of the above in two cases of subsequent Histamine administration against once accentuated LSD symptoms through AH, a marked alleviation of the symptoms was realized, too. All in all, the authors are of the opinion that the AH effect is produced by the inhibitory action of its own against normally pre-existent Histamine portion.