Reconstruction of the oral cancer patient should aim not only at morphological restoration but also at postoperative functions. However, there are few reports about quantitative evaluation of postoperative functions. We have attempted quantitative evaluation of post operative articulatory function after glossectomy, and report about evaluation of articulatory characteristics by acoustical analysis, speech intelligibility, electropalatography (EPG), and visual examination. Subject had a reconstructed a forearm flap after glossectomy. Target syllables were/ta/and/ka/from a speech intelligibility test. To evaluate the articulatory function, we used a speech intelligibility test, EPG, and visual examination. We also attempted evaluation by acoustical analysis. The speech intelligibility was tested just before, and 1, 3, 6, and 12 months after operation. EPG data was corrected 6 months after operation by DP-01 (RION). Visual examination was carried out with other tests. Acoustical analysis were carried out by consonant frequency characteristics and formant variance from consonant to vowel transitions. As a result, articulatory characteristics expected from acoustical analysis agreed with the results of EPG, and visual examination, more than with the results of the speech intelligibility test. From the results, it is suggested that the acoustical analysis used for this research, could reveal changes in articulatory movement, and will be useful to quantitatively evaluate postoperative articulatory functions.
α-tricalcium phosphate (α-TCP) granules were mixed with calcium phosphate dibasic (DCPD) and hydrated to obtain hardened materials. These materials were shaped in the form of column (2×10 mm), and then implanted on the inferior surface of rabbit mandibles and in the muscle tissue with and without calvarial periosteum and soaked in simulated body fluid for 1, 3, and 6 months. The changes of the materials were evaluated microscopically and microradiographically. The surface resorption was recognized in all materials except ones soaked in simulated body fluid. The resorption was most prominent on the surface of the materials implanted on the mandibular bone. Microradiographic study showed the formation of white zone in the outer part of the materials implanted on the mandibular bone and in the muscle tissue with calvarial periosteum. The white zone was formed on the entire surface of the materials implanted on bone, however, it was only on partial surfaces of the materials where calcified tissue was formed when implanted in the muscle tissue with periosteum. The white zone formation was not recognized on the materials soaked in the simulated body fluid. It is concluded that the materials are resorbable in vivo, and the surface of the materials may develop the change, resulting in the decrease of radiolucency, in the circumstances where bone or calcified tissue is formed.
To test that callotasis can be used for ridge augmentation, the present experiments were performed in dogs. In the experimental group, ridge augmentation by callus distraction was performed; in the control group ridge was augmented in a single period. New bone formation in the distraction gap was evaluated radiographically and histologically. In the experimental group, most of ridges were structurally stable after removal of the distraction appliances, and all of the dogs were able to eat hard pellet food. Radiographically, radiopaque appearance could be seen throughout the distraction gap. But the distraction gap was still less radiographically dense than the pre-existing mandible. Histologically, in the lingual area numerous new bone formations aligned in the direction of distraction could be seen throughout the distraction gap. In the center of the distraction gap, osteoblasts could be seen around new bone formations. New bone formation bordering on the pre-existing mandible and transport disk demonstrated lamellar structure. In the buccal area a lot of fibrous connective tissue could be seen, but little new bone formation could be seen. In the control group, most of the transport disks were widely exposed during the distraction process, and suffered from major infections. Radiographs showed that most of the distraction gap was filled with radiolucent appearance. Histologically, the central area of the distraction gap was filled with fibrous connective tissue, though a little new bone formation could be seen around the transport disk and preexisting mandible.
The purpose of this study was to investigate the correlation between the maximal opening and skeleton in dental students of our school without functional disorders of the masticatory system. In 99 males and 86 females, the stature and maximal opening were recorded. Out of these subjects, 29 males and 31 females agreed to have lateral cephalogram taken in both the closed and maximal opening positions. The results were as follows. 1. The correlation between the maximal opening and stature, and mandibular length or mandibular angle were significant. 2. The correlation between the maximal opening and the movement of the condyle was significant. 3. The correlation between the movement of the condyle and the distance of the Sera-Nasion was significant. 4. It became evident from these studies that the maximal opening was in close relation to the size of the skeleton.
The pallor of the skin and oral mucosa that is associated with anemia is thought to be due to a decrease in hemoglobin in the super ficial blood vessels. However, there has been little systematic research on this subject. The authors of this paper used a tissue spectrum analyzer to measure the Lib (indicating hemoglobin concentration) and the Iso2 (indicating saturation). Experiments were conducted to determine the relationship between anemia and hemoglobin level in the oral mucosa, using the hemoglobin (Hb) value as the indicator. The following conclusions were reached. 1. The areas of the oral mucosa which best correlate with the blood Hb level are the upper labial mucosa, lower labial mucosa, the back of the tongue, the sublingual surface, and the soft palate. The patients with secondary anemia showed reduced Lib levels (i. e. anemia) in all of these areas. 2. Measurements of IHb were graded to appear in the following order, from highest to lowest: labial mucosa, tongue, and then soft palate. 3. These measurements did not show a definite relationship between the IHb and the is in either patients with secondary anemia or in normal healthy people. 4. It was conjectured that patients on dialysis would tend to show a somewhat higher IHb on the back of the tongue than in other areas. 5. Sudden changes in blood volume, as in transfusions, surgery, etc., influence the oral mucosal hemodynamics. Reductions in the blood volume of thebody as a whole are accompanied by reductions in the blood volume of the oral mucosa. It was conjectured that the degree of this change in the oral mucosa would increase as the severity of anemia increased. 6. Among the five parts of the oral mucosa which were investigated, the back of the tongue showed the lowest correlation with the true state of anemia. 7. In order to determine the degree of anemia by hemodynamics of the oral mucosa, it is thought that the four parts (the upper and lower labial mucosas, the lower part of the tongue, and the soft palate) are the most reliable ones to observe. From the above, it was concluded that, in secondary anemia (patients on dialysis, those having blood dyscrasis, a malignant tumor of the oral cavity, etc.), there is a distinct correlation between the tissue hemoglobin concentration (IHb) in the mucous membranes of the oral cavity and the true degree of anemia. This could be considered a useful method for clinical diagnosis.
The purpose of this study was to investigate the time of change in the reaction between mandibular bone tissue and glass ceramic implants under functional loads. Two months after extraction of P2, P3, P4, and Ml, from the mandibles of 16 adult mongrel dogs, glass ceramic implants were implanted in each side, and the glass ceramic implants were under a functional load three months after implantation. Histological examination and tetracycline labelling of the specimens were made 10 to 300 days after initiation of the function. The results obtained were as follows: At 10 to 30 days after initiation of the function, new bone formation was found around the glass ceramic implant, the new bone increased in thickness and ankylosed, showing a network structure. After 60 to 90 days, there was new bone formation and bone remodeling, after 120 to 150 days, there was a supporting growth of spongy bone tissue, and the new bone was mature. After 300 days, the functional load was around the implant and the mandible bone. The tetracycline labelling method showed strong labelling after 10 to 30 days continuing up to 60 days and then decreasing gradually until 90 days. The results of this experiment confirmed that glass ceramics has high tissue affinity for mandibular tissue and the placement of the glass ceramic implants under functional loads caused no problems around the implant. We established that it is an appropriate material for implants.
Cytokeratin distribution in salivary glands was detected by use of polyclonal antikeratin antiserum (TK) and monoclonal antibodies (KL 1, RGE 53, and RPN 1164). The salivary glands of male rats received either 17. 82 Gy or 27.97Gy 60Coγ irradiation in a single exposure and were then compared immunohistochemically with those of normal rats. The following results were obtained. 1. Polyclonal anti-keratin antiserum (TK), which reacts with 41-65 KD keratins, stained almost all ducts in normal glands. RPN 1164 (No.8 keratin) staining was negative in intercalated ducts of normal parotid and submandibular glands, but strongly positive in both striated and excretory ducts of these glands. Monoclonal antibody KL 1 (55-57 KD keratins) and RGE 53 (No.18 keratin) did not bind to any ductal or acinar epithelia. 2. Only in the sublingual gland were acini positive for TK staining, possibly indicating myoepithelial cells. 3. No effects of 60Coγ irradiation were apparent regarding keratin distribution in the intercalated duct. 4. In striated duct cells, positive staining was lost in basal and perinuclear portions and restricted in apical cytoplasm by 60Coγ irradiation. 5. Also, in the excretory duct, the basal side of the cells exhibited weakened staining following 60Coγ irradiation. 6. Although the histology suggested that 60Coγ irradiation diminished in size of the granular convoluted tubule, no remarkable changes in keratin deposition were found. 7. In striated ducts, changes in keratin distribution following 60Coγ irradiation were the most significant in the parotid and the least in the sublingual gland. Also this reaction depended upon the doses of 60Co used. The present findings suggested that negative or weakened staining at the basal and perinuclear portions of striated duct cells specifically reflects the primary or secondary cell damage produced by 60Coγ irradiation. Since the distribution of cytoskeletal proteins in the cytoplasm reflects certain pathological conditions, immunohistochemical detection of these proteins seem to have a diagnostic value with respect to cellular injury.
Vascularized free fibular flaps, raised with associated skin island, has been used to reconstruct a large mandibular defect including the middle third of the mandible in two cases. Although additional surgical procedure to correct the shape of the graft was needed in one patient, a fibular bone could be molded to the appropriate contour by means of osteotomies and fixations with miniplates in both cases. The small skin island was used for the purpose of monitoring the blood supply to the bone graft in one patient, and the large skin island was employed for covering the skin defect of the recipient site in the other. In the former patient, in spite of partial necrosis of the monitoring skin island, the bone graft survived completely. The latter had no trouble in the recipient site with survival of the bone and skin grafts. However the latter patient had trouble in the donor site with a slight functional deficit caused by prolonged wound infection. These two cases have taught us that vascularized free fibular graft is useful in reconstruction of mandibular defect particularly in such a large segment as this; however, the problems relating to the skin island or management of the donor site must be considered.
We have investigated the recurrence rate after surgical treatment of odontogenic keratocysts in basal cell nevus syndrome (BCNS) and non-BCNS patients, and examined the excised specimens histologically. Twenty-five cysts from 6 BCNS patients and one each from 17 non-BCNS patients were enrolled in this study. All of them had been histologically diagnosed as odontogenic keratocysts. These cysts were either extirpated or marsupialized. The patients were followed up and checked clinically and roentgenologically for three years postoperatively. The recurrence rate was much higher in BCNS patients than in non-BCNS patients. The extirpation of the cysts resulted in the recurrence of 8/21 instances (38.1%) in BCNS and 2/15 (13.3%) in non-BCNS patients. Furthermore, recurrence was observed in 2/4 (50.0%) of the BCNS patients who underwent marsupialization of the cysts, but in none (0/2; 0%) of the non-BCNS patients. Next, we examined the excised specimens histologically for the presence of the following features: i) infoldings of the cyst wall, ii) satellite cysts, iii) growth patterns like dental lamina, iv) islands of epithelial cells, v) proliferation of rete ridges, and vi) inflammatory cell infiltration. All features except inflammatory cell infiltration were demonstrated more markedly in the cysts from BCNS patients than in those from non-BCNS patients. In BCNS cysts (n=19), features i), ii), iii), iv), v), and vi) were present in 57.9%, 52.6%, 73.7%, 52.6%. 31.6%, and 15.8% of the cases, respectively, whereas in non-BCNS cysts (n=17) these features were observed in 35.3%, 41.2%, 47.1%, 29.4%, 11.8%, and 64.7% of the cases, respectively. These findings suggest that the epithelium of cysts in BCNS patients has a higher growth rate than that of cysts in non-BCNS patients, which would explain, at least in part, the higher recurrence of cysts in BCNS patients.