Maxillary distraction osteogenesis combined with mandibular osteotomy to correct asymmetry of the maxillomandibular complex.
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Adult↗
Biomedical subjects
Tetsu Takahashi
Publications and source records attributed to Tetsu Takahashi.
Reduced syndecan-1 expression is correlated with the histological grade of malignancy at the deep invasive front in oral squamous cell carcinoma.
BACKGROUND: Although many histopathological characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, no factor is completely accurate and unequivocal. This study evaluated the association between the loss of syndecan-1 expression and the histological grade of malignancy at the deep invasive front in O-SCC. METHODS: The expression of syndecan-1 at the invasive tumor front of O-SCC was examined immunohistochemically using archived tissue from 72 cases. The mean age of the patients was 62.5 years (range: 23-90 years) and the male-female ratio was 1.3:1 (41 men, 31 women). There were 26, 24, 11, and 11 cases classified as stages I-IV respectively. The correlation between the intensity of syndecan-1 immunostaining and the clinicopathological factors, especially the histological grade of malignancy at the deep invasive front (invasive front grade) was analyzed. RESULTS: Of the 72 cases, seven (9.7%), 29 (40.3%), 36 (50.0%) showed strong, intermediate, and weak or negative syndecan-1 staining respectively. There were significant differences between syndecan-1 expression and prognosis, differentiation, and pattern of invasion at the deep invasive front. Moreover, the invasive front grade scores, based on the intensity of syndecan-1 staining, were 5.6 +/- 1.0, 8.0 +/- 2.1, and 10.2 +/- 2.3 points with strong, intermediate, and weak or negative intensity respectively; and the difference was significant (P < 0.0001). Patients with intermediate or strong intensity for syndecan-1 had significantly better prognoses than did those with negative or weak intensity (P = 0.0138). CONCLUSION: This study demonstrated that the reduced expression of syndecan-1 seems to be a useful marker of histological malignancy at the deep tumor invasive front and may be a useful prognostic factor in O-SCC.
Adult↗
A psychological study on patients with masticatory muscle disorder and sleep bruxism.
Sleep bruxism (SB) has been believed to be related to stress and psychosocial factors, however their implicit relationship has remained unclear. This study was conducted on patients visiting our clinic with SB and masticatory muscle disorders (MMD) for the purpose of clarifying personality and behavioral traits. This study was conducted on patients of MMD visiting our clinic. The Rosenzweig Picture-Frustration study was performed on each patient. Twenty-seven (27) patients were divided into two groups: 17 patients with SB and 10 patients without. The SB group showed a significantly lower level of E (extrapunitive) reaction than the nonSB group. SB patients showed a significantly higher level of M (impunitive) reaction than those without SB. Concerning the directions of aggression, the percentage of E-A (extraaggression) was significantly lower in SB patients than in those without. On the other hand, the percentage of I-A (intraaggression) was significantly higher in patients with SB than those without. Our study found a new aspect of the patients with MMD and SB: they are not only intraaggressive, but are also unable to be extrapunitive and extraaggressive. Consequently, they are unable to demonstrate adequate self-assertiveness in stressful situations.
Adolescent↗
Utility of diffusion-weighted images using fast asymmetric spin-echo sequences for detection of abscess formation in the head and neck region.
OBJECTIVE: The objective of this study was to evaluate the utility of new diffusion-weighted magnetic resonance images (DWI) using fast asymmetric spin-echo (FASE) sequences for the detection of abscess formation in patients with phlegmon in the oral and maxillofacial regions. METHODS: We compared diffusion-weighted images using FASE sequences with those using the gradient-echo type of echo-planar images (EPI) in 10 control volunteers and 10 patients with phlegmon in the oral and maxillofacial regions. RESULTS: Many kinds of tissues in the oral and maxillofacial regions were relatively well visualized in all subjects on FASE-DWI, but not well on EPI-DWI. Apparent diffusion coefficients calculated from FASE sequences in abscess areas of patients with phlegmon were significantly lower than those in abscess-free areas; however, apparent diffusion coefficients calculated from EPI were not significantly different due to prominent distortion in small sample size study. CONCLUSIONS: We could accurately recognize the presence of abscess formation within inflammatory tissue in 5 patients with phlegmon using FASE-DWI. As an additional magnetic resonance examination, FASE-DWI might be useful in the detection of abscess formation in the oral and maxillofacial regions.
Abscess↗
Mechanisms involved in enhancement of osteoclast formation and function by low molecular weight hyaluronic acid.
Hyaluronic acid (HA) is a component of the extracellular matrix that has been shown to play an important role in bone formation, resorption, and mineralization both in vivo and in vitro. We examined the effects of HA at several molecular weights on osteoclast formation and function induced by RANKL (receptor activator of NF-kappa B ligand) in a mouse monocyte cell line (RAW 264.7). HA at M(r) < 8,000 (low molecular weight HA (LMW-HA)) enhanced tartrate-resistant acid phosphatase-positive multinucleated cell formation and tartrate-resistant acid phosphatase activity induced by RANKL in a dose-dependent manner, whereas HA at M(r) > 900,000 (high molecular weight HA (HMW-HA)) showed no effect on osteoclast differentiation. LMW-HA enhanced pit formation induced by RAW 264.7 cells, whereas HMW-HA did not, and LMW-HA stimulated the expression of RANK (receptor activator of NF-kappa B) protein in RAW 264.7 cells. In addition, we found that LMW-HA enhanced the levels of c-Src protein and phosphorylation of ERKs and p38 MAPK in RAW 264.7 cells stimulated with RANKL, whereas the p38 MAPK inhibitor SB203580 inhibited RANKL-induced osteoclast differentiation. This enhancement of c-Src and RANK proteins induced by LMW-HA was inhibited by CD44 function-blocking monoclonal antibody. These results indicate that LMW-HA plays an important role in osteoclast differentiation and function through the interaction of RANKL and RANK.
Acid Phosphatase↗
Neuropeptide substance P stimulates the formation of osteoclasts via synovial fibroblastic cells.
The present study was designed to evaluate the effects of neuropeptide substance P (SP) on the formation of osteoclasts via synovial fibroblastic cells. Synovial fibroblastic cells derived from rat knee joint expressed the SP receptor, neurokinin-1 receptor (NK(1)-R). The addition of SP stimulated the proliferation of synovial fibroblastic cells and this effect was inhibited by SP or NK(1)-R antagonists. Increased expression of the receptor activator of nuclear factor kappaB ligand (RANKL) in synovial fibroblastic cells after the addition of SP was demonstrated by reverse transcriptase-polymerase chain reaction and immunofluorescence staining. Osteoprotegerin expression in synovial fibroblastic cells was decreased after incubation with SP. In co-cultures of synovial fibroblastic cells and rat peripheral blood monocytes, SP stimulated osteoclastogenesis. These results suggest that SP in the joint cavity may cause both hypertrophy of the synovium and induction of increased osteoclast formation through the increased expression of RANKL in the synovium.
Animals↗
Platelet-rich plasma enhances human osteoblast-like cell proliferation and differentiation.
PURPOSE: Platelet-rich plasma (PRP) is widely used to promote tissue healing. However, there is no concrete evidence for the biological effects of PRP. This study evaluated the biological effects of PRP on the proliferation and differentiation of 2 human osteoblast-like cell lines. MATERIALS AND METHODS: Human osteosarcoma cell lines HOS and SaOS-2 were used in this study. PRP was prepared from freshly drawn human venous blood containing a large number of platelets. The MTT assay was used to examine the effects of PRP on osteoblast viability. To evaluate the growth and differentiation, alkaline phosphatase activity was assessed and the expression of procollagen type I, osteopontin, and osteoprotegerin mRNA was measured using semiquantitative reverse transcriptase-polymerase chain reaction. Further, core binding factor alpha 1 (cbfa1/Runx2/AML3/PebpalphaA), a critical regulator of osteoblast differentiation, was also determined. RESULTS: The administration of PRP enhanced the viability of HOS and SaOS-2 cells in a dose-dependent manner. Alkaline phosphatase activity was suppressed during the cell growth phase, but was strongly enhanced when the cells reached confluence. Semiquantitative reverse-transcription polymerase chain reaction analysis showed that PRP enhanced the levels of procollagen type I, osteopontin, osteoprotegerin, and core binding factor alpha 1 (cbfa1) mRNA. CONCLUSION: These results suggest that PRP has a favorable effect on human osteoblast-like cells, and acts both to enhance bone regeneration and as an activator in wound healing.
Alkaline Phosphatase↗
Tensile mechanical strain up-regulates Runx2 and osteogenic factor expression in human periosteal cells: implications for distraction osteogenesis.
PURPOSE: Distraction osteogenesis is now accepted as a standard treatment in oral and maxillofacial reconstructive surgery. In the process of bone regeneration with the application of strain, the periosteum might be very involved in osteogenesis. This study examined the effect of mechanical strain on periosteal cells and the implications for distraction osteogenesis. MATERIALS AND METHODS: Periosteal cells were obtained from mandibular periosteum that was excised while extracting impacted wisdom teeth. Mechanical strain was applied using a specially designed apparatus with flexible silicon bottom chambers. The levels of mRNA of the osteoblast differentiation factor Runx2 (Cbfa1/AML3/Peb alpha A) and osteogenic factors were analyzed at different times using the reverse transcription-polymerase chain reaction method to evaluate the effect of the strain. RESULTS: The periosteal cells expressed the osteogenic phenotype. The strain had a shaping effect on the cells. The application of tensile strain strongly activated the expression of osteogenic and angiogenic growth factors, and up-regulated the expression of Runx2, an osteoblast-specific transcription factor. CONCLUSION: Tensile strain may initiate the differentiation of periosteal cells into osteogenic cells, inducing the expression of Runx2 in the process of bone regeneration. Therefore, the periosteum is profoundly involved in bone formation and regeneration, especially in distraction osteogenesis.
Bone Regeneration↗
Use of an alveolar distraction device for repositioning the maxillary segment to correct asymmetry of the maxillomandibular complex.
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Adolescent↗
Three-dimensional identification of hemangiomas and feeding arteries in the head and neck region using combined phase-contrast MR angiography and fast asymmetric spin-echo sequences.
OBJECTIVE: To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences. METHODS: The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography. RESULTS: In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed. CONCLUSIONS: Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium.
Adult↗
The relationship of the histologic grade at the deep invasive front and the expression of Ki-67 antigen and p53 protein in oral squamous cell carcinoma.
BACKGROUND: Although many histopathologic characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, accurate, and unequivocal factors have not been clearly identified. The purpose of this study was to evaluate a potential association between the histologic grade of malignancy at the deep invasive front and the expression of Ki-67 antigen and p53 protein in O-SCC. METHODS: The expression of Ki-67 antigen and p53 at the invasive tumor front area of O-SCC was examined by immunohistochemistry of archived tissue from 62 cases. The mean age of patients was 60.7 years (range: 37-89) and the male-female ratio was 1.6:1 (38 men, 24 women). There were 20, 17, 14, and 11 cases classified as stage I to stage IV, respectively. The correlation between the intensity of immunostaining for Ki-67 antigen and p53 and the histologic grade of malignancy at the deep invasive front (invasive front grade, IFG) was analyzed. The expression of Ki-67 antigen and p53 in normal oral epithelia (10 cases) was also investigated. RESULTS: The mean Ki-67 labeling index (LI) in the O-SCC samples was 32.8 +/- 12.0% (n = 62). The mean total score of IFG (IFG score) was 9.1 +/- 2.7 points (n = 62). There was a significant linear correlation between the IFG score and the Ki-67 antigen (gamma = 0.651, R2 = 0.596, P < 0.0001). Of 50 tumors examined, 27 (54.0%) exhibited p53-positive nuclear immunostaining. The staining patterns for Ki-67 antigen and p53 were similar. Both Ki-67-LI and p53-positive status were significantly correlated with the IFG scores. CONCLUSION: The findings of this study demonstrate that overexpression of Ki-67 antigen and p53 at the deep tumor invasive front of O-SCC is associated with histologic grade of malignancy.
Adult↗
[Clinical implication of bone regeneration in oral surgery].
Bone augmentation or the alveolar ridge augmentation procedure is inevitable for functional and esthetic prosthetic oral rehabilitation. In this article, conventional alveolar ridge augmentation methods are clinically demonstrated and are reviewed with reference to literature. In addition, distraction osteogenesis (DO), which has drawn considerable attention as a regenerative medicine, was clinically demonstrated. Then, the conventional augmentation methods and distraction are compared. Indications, advantages, and disadvantages of conventional augmentation methods including bone grafts, guided bone regeneration (GBR) and GBR with titanium micromesh (TIME technique) are demonstrated. Next, the mechanisms, indications, and advantages of DO are demonstrated and compared with conventional methods. Although conventional augmentation methods are well established, there are some problems including donor site morbidity and risks of wound dehiscence and infection. DO seems to have advantages compared to conventional augmentation methods. However, there still have some clinical problems such as difficulty in vector control and technique sensitivity. For less morbidity and better efficacy in alveolar ridge bone augmentation, tissue engineering offers potential in the future. However, further basic and clinical study will be necessary for clinical application.
Alveolar Ridge Augmentation↗
IL-1 beta, IL-1 receptor antagonist and soluble type II IL-1 receptor in synovial fluid of patients with temporomandibular disorders.
Among the members of the interleukin-1 (IL-1) family, IL-1 beta, which is a major agonist, has been detected in synovial fluid (SF) of the temporomandibular joint (TMJ) of patients with temporomandibular joint disorders (TMD). However, there is little knowledge regarding suppressive molecules, such as IL-1 receptor antagonist (IL-1ra) and the soluble form of type II IL-1 receptor (sIL-1RII), in TMD patients. The aim of this study was to investigate the levels of IL-1 beta, IL-1ra and sIL-1RII in the TMJ SF of patients with TMD and their relationship. Fifty-two SF samples from TMD patients and nine samples from asymptomatic volunteers were examined. Detected levels of IL-1 beta and sIL-1RII were significantly higher in the TMD group compared with the volunteer group. There was no significant difference in IL-1ra levels between the TMD and volunteer groups. The IL-1 beta/IL-1ra ratio in the TMD group, however, was higher than that in the volunteer group. In the TMD group, positive correlations were found between IL-1 beta and IL-1ra, IL-1ra and sIL-1RII, and IL-1 beta and sIL-1RII. In addition to increased IL-1 beta, development of TMD may also lead to decreased IL-1ra and increased sIL-1RII in response to increasing IL-1.
Adolescent↗
Two-stage distraction osteogenesis for mandibular segmental defect.
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Ameloblastoma↗
Implant-supported edentulous maxillary obturators with milled bar attachments after maxillectomy.
PURPOSE: The purpose of this study was to evaluate the clinical results of implants and milled bar supported edentulous maxillary obturators following the surgical ablation of maxillary tumors. PATIENTS AND METHODS: Seven patients with malignant tumors of the maxilla were studied. All patients underwent partial or total maxillectomy. Implants were installed in the remaining maxilla and milled bar supported obturators were fabricated. Masticatory efficiency, biting abilities, speech function, and changes in the marginal bone level around the implants were evaluated without the prostheses, with the previous prostheses, and with the implant-supported prostheses. RESULTS: All implants were osseointegrated. All patients wore milled bar supported obturators and masticatory and speech functions markedly improved. There was no complication during the follow-up period. CONCLUSIONS: These results suggest that a maxillary obturator supported by milled bar attachments is useful for oral rehabilitation in patients with resected edentulous maxilla.
Aged↗
Use of a new instrument for lateral release in arthroscopic surgery of the temporomandibular joint: a preliminary study.
We developed a new instrument, which we call a lateral releaser, to improve the safety of either a blind lateral release or lateral stretching within the TMJ We used it during arthroscopic surgery in patients with chronic painful hypomobility of the temporomandibular joint (TMJ). We operated on 24 TMJs in 17 patients (15 women and 2 men). At operation, the mean increase in the interincisal distance was 22 mm (range 10-32). No instruments were broken. No serious surgical complications were reported during or after operation. Many of the patients currently have an interincisal distance exceeding 38 mm.
Adult↗
A decrease in the molecular weight of hyaluronic acid in synovial fluid from patients with temporomandibular disorders.
BACKGROUND: The molecular weight (MW) of hyaluronic acid (HA) in joints generally declines in inflammatory arthritis. As inflammation exists in certain temporomandibular disorders (TMD), we measured the MW of HA in synovial fluid (SF) recovered from patients with TMD and compared it with that from normal controls. METHODS: Synovial fluid was obtained from patients with TMD (21 TMJs) and normal controls (5 TMJs). The MW of HA was measured using high-performance liquid chromatography (HPLC). RESULTS: In the controls, the MW of HA in SF exceeded the detection limit, 3000 kDa. In contrast, 19 (90.5%) of 21 SF samples from patients showed a decreased MW of HA. The median MW of HA (1570 kDa) in TMD was significantly lower than that in the controls (P < 0.01). CONCLUSION: The MW of HA in SF from patients with TMD is decreased.
Adolescent↗
Magnetic resonance evidence of joint effusion of the temporomandibular joint after fractures of the mandibular condyle: a preliminary report.
To investigate the clinical significance of magnetic resonance (MR) evidence of joint effusion of the temporomandibular joint after mandibular condylar fractures, magnetic resonance imaging (MRI) was performed on 18 joints in 15 patients with either unilateral or bilateral mandibular condylar fractures using a 1.5 Tesla MRI scanner (Signa, General Electric, Milwaukee, WI). MR evidence of joint effusion was evaluated and compared with the types and the positions of the fractures. MR evidence of joint effusion was observed in 11 of 18 TMJs, which was 61% of the condylar fractures. It appeared more frequently after fractures with dislocation than those without dislocation (p < 0.05). In addition, MR evidence of effusion appeared more frequently in TMJs after high condylar fractures (head to upper neck) than low condylar fractures (lower neck to subcondylar) (p < 0.05). These findings indicate that MR evidence of joint effusion may serve as a marker for the detection of severe intra-articular damage to the TMJ after mandibular condyle fractures.
Adolescent↗