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We report the case of a patient with lifelong symptoms of xerostomia and a repaired bilateral cleft lip and palate. The clinical evaluation demonstrated aplasia of the major salivary glands. A review of the literature pertaining to salivary gland aplasia is presented, along with a summary of the data regarding patient gender, defect sites, hereditary background, and combined manifestations. The diagnostic methods, possible pathogenesis, and management are also discussed.

Objective. The purpose of this study was to investigate the reactions of bone tissue after the placement of implants into the tibiae of osteopenic model rats. Study design. Commercially pure titanium screw implants were placed in the bilateral proximal tibial metaphyses 168 days after ovariectomy had been performed on 12-week-old female Wistar rats. For control purposes, implants were similarly placed in sham-ovariectomy rats. The healing process was examined histologically by means of undecalcified sections at various intervals from 7 to 168 days after implantation. Through use of an automated imaging analytic system, changes in relative bone mass and implant-bone contact were histomorphometrically evaluated. Results. In the cortical bone area, only a slight difference in bone contact was noted with the implant until 28 days after implantation. However, ovariectomy significantly affected bone contact at 56 days after implantation. The rate of bone contact in the cancellous bone area and the relative bone mass around the implant were significantly lower in the test group than in the control group. Conclusions. It is considered that a decrease in bone mass causes a reduction in the contact area between implant and bone and may also cause a reduction in the supporting ability of the implant because of thinning of the surrounding bone tissue. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;87:411-8)

Objective. The purpose of this study was to investigate bone reaction after implantation in an estrogen-deficient state by examining the changes in bone reactions within tissue surrounding implants in ovariectomized rats. Study Design. Ninety-six 12-week-old female Wistar rats were used in the study; they were divided into 2 groups, an ovariectomized group and a sham-operated group. Hydroxyapatite-coated implants were placed in the proximal metaphyses of the tibiae 21 days after surgery. The tibiae were examined histologically by undecalcified sections at various intervals from 7 to 168 days after surgery. Results. In the cortical bone area of the ovariectomized rats, the procedure did not induce any apparent changes in bone volume around the implant or in bone contact with the implant in comparison with the sham-operated rats. In contrast, both bone volume around the implant and contact of the implant with new bone were significantly decreased in the cancellous bone area in the ovariectomized rats in comparison with the sham-operated rats. Conclusions. Ovariectomy did not seriously affect bone healing after the placement of implants in cortical bone areas, but it reduced the bone contact ratio and the bone in the cancellous bone area. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;87:145-52)

Material/Method. In six miniature pigs revascularized autologous iliac crest bone grafts were fixed with two 2.0 mm titanium miniplates to a defined defect in the angle of the mandible. Tissue reaction around the implants was examined histologically and histomorphometrically at 2, 4, and 8 weeks after surgery. Results. According to the evaluation of fluorescence microradiography, the cortical and medullary circulation and healing processes of bone in the vicinity of the implanted material were not disturbed after 2 weeks. At 4 weeks after surgery osseous healing occurred at the mandibula/graft interface. The histomorphometric results for the calculated percentage of direct bone/screw contact at 2 weeks were 24% with the grafted bone and 53% with the mandible. Intensive bone formation was observed in all parts of the graft by 4 weeks. The results of direct bone/screw contact at 4 weeks were 56% and 64% and at 8 weeks 75% and 77% for the grafted and the mandibular bone, respectively. Conclusion. With 2.0 mm titanium miniplates used in the animal model, stable osteosynthesis and osseous healing was evident after 8 weeks of surgery. In addition, intensive remodeling of the transplanted bone without signs of creeping substitution was noted, and the bone/screw contact of the miniplate system increased with time.

The purpose of the present study was to establish the clinicoanatomical basis for the radial forearm flap. We conducted a morphometric investigation on 52 Japanese cadavers, of forearm vessels, for use in free forearm flaps. The mean inner diameter of the cephalic and median cubital veins at the interepicondylar line was 1.9 +/- 1.2 mm and 1.8 +/- 1.1 mm, respectively. Mean inner diameter of the radial artery and venae comitantes 1 cm distal to the origins of the radial and ulnar arteries was 2.3 +/- 0.5 mm and 1.6 +/- 0.5 mm, respectively. The longest segment of a superficial vein was 28.7 +/- 4.6 cm, it was measured between the basilic vein 5 cm proximal to the interepicondylar line and the cephalic vein at Lister's tubercle. The length of the radial artery was 18.1 +/- 1.7 cm. There were fewer valves in the basilic vein and cephalic vein proximal to the median cubital vein and in the brachial veins than in the distal antebrachial veins. From these results some of the clinicoanatomical considerations of forearm vessels which will form the clinicoanatomical basis of the free forearm flap should be clarified.

Purpose: The study evaluated the processes of incorporation and bone remodeling after microsurgical transplantation of iliac crest grafts for mandibular defect reconstruction. Materials and Methods: A defect in the mandibular angle measuring 2 × 4 × 1 cm was reconstructed in six Gottingen minipigs with a microvascularized iliac bone graft based on the circumflex artery. The animals were killed at 14, 28, and 56 days after transplantation and the healing process was histologically examined. Results: Although a constant vascular supply to the graft was restored by the microvascular reanastomosis, necrosis occurred in the major part of the bone marrow. New bone formation from the graft was markedly delayed compred with that from the mandible. Some osteocytes and marrow survived after grafting, but the volume of iliac bone tended to decrease gradually over time. In the 56-day specimens, the border between the graft and the mandible was not clear. Conclusion: These findings indicate that survival of the vascularized iliac bone graft in the minipig is not complete.

This study investigated the effect of age and radiation on healing after implantation of hydroxyapatite granule in bone. Two groups of 16 male Wistar rats, aged 4 weeks and 2 years were used for this study. Hydroxyapatite particles were placed into the tibia 28 days after the delivery of 15 Gy of irradiation from a Linac source. The results of the present study suggest that an old rat was more vulnerable to the radiation than a young rat. It seemed that age might also be an important factor in the prognosis of the implanted hydroxyapatite in irradiated bone.

Reaction of bone tissue was investigated after placement of two different types of implants in vascularized iliac bone grafting. After the mandibles of six Gottingen minipigs were reconstructed with vascularized bone of the iliac crest, hydroxyapatite-coated implants and titanium screw implants were placed in the graft. The animals were killed at 14, 28, and 56 days after the implantation, and the healing processes were examined histologically. In the vascularized bone graft, new bone formed well around the implants, but some of the implant surfaces were covered with soft tissue by advancing bone resorption. The results suggest that a hydroxyapatite-coated implant as well as a titanium screw-type implant might be applied with a vascularized bone graft for jaw reconstruction. However, implants placed simultaneously with the vascularized bone graft had less osteointegration than implants placed in nongrafted control sites.

The effects of calcium phosphate ceramic implants on tooth eruption were investigated radiographically and histologically in 20 3-month-old dogs. Four kinds of ceramic particles were used: dense and porous hydroxyapatite particles, and dense and porous tricalcium phosphate particles. These particles were implanted in the sockets after decidous tooth extraction. The four types of calcium phosphate ceramic particles produced similar radiographic and histologic findings. There was no delay of tooth eruption, no dysplasia, and no resorption of dental hard tissue.

The valves of the cephalic, basilic and median cubital veins were investigated in the superficial veins of the left forearm in 9 cadavers, aged 25-95. The radial forearm flaps involving these veins are of special clinicoanatomical importance. The following results were obtained: (1) Valves were most frequently evident at Site G of the cephalic vein. No valves were present in Section A-B, (2) type B valves were located at confluences, junctions and branches and were more frequent (54.7%) than Type A (45.3%) located in the straight trunks of superficial forearm veins, (3) Type 2 valves accounted for most (82.3%), and these were followed by Type 1 and Type 4b (5.9%), Type 4a (4.4%) and Type 3 (1.5%).

The purpose of this study was to evaluate the use of hydroxylapatite implants (HA) with autogenous bone grafts for jaw reconstruction. After autogenous iliac bone grafts were transplanted to 36 rabbit mandibles, an HA implant was installed into the graft immediately (IM group), or 90 days (90D group), or 180 days (180D group) later. The animals were killed 7, 14, 30, 60, 90, and 180 days after the HA implant placement. The healing process was examined histologically, and histomorphometric measurements were made with a computer-based image analyzer to quantify the percentage of HA-bone bonding and trabecular bone in the medullary cavity. In the IM group, the HA-bone bonding tended to be deterred by fibrous tissue, and the rate of HA-bone bonding (BBSR) was less than that of the other groups. The trabecular bone around the implants tended to decrease after 30 days in all groups. However, the average of the trabecular bone specific volume (tVsp) in the 90D group was about 10% higher than that in the other groups. From these results, it is concluded that in clinical use of HA-coated dental implants with autogenous bone grafts, the time of installation should not be immediately after the bone graft, but when there is sufficient newly formed trabecular bone to enhance HA-bone bonding.

Summary Postoperative follow-up and multiple regression analysis of skeletal relapse following mandibular setback were carried out to clarify the timing and causes of the relapse. The subjects were 24 mandibular prognathism patients. All patients underwent intraoral oblique sagittal splitting osteotomy with circumferential wiring and intermaxillary fixation for 8 weeks. Occlusal splints were not used. Postoperative positional changes of segments were evaluated by lateral cephalograms taken at appropriate intervals. Horizontal relapse was most evident within six months after surgery; vertical relapse seldom occurred. Multiple regression analysis revealed little association between preoperative morphological patterns and postoperative relapse. Although spatial changes of the proximal segment at operation and age of the patient were the best predictors for postoperative horizontal relapse, analysis indicated unsatisfactory prediction of vertical relapse because of its rare occurrence. Based on these results, the aetiology of relapse is discussed and two proposals are suggested for its prevention.

ESR measurements have been used to monitor radiation damage in ion-implanted silicon. When the Ar implantation dose is more than about 10 times the critical one for amorphization, both an amorphous center with g = 2.0055 and another new ESR center with g = 2.0029 can be observed. An investigation of heavily argon implanted layers in silicon was characteristically carried out using ESR and ESCA, and was structurally studied using transmission electron microscopy. It is found that the new ESR center in heavily implanted layers is due to amorphous SiC.

A new ESR center at g=2.0029 which was first observed by Chu et al. in silicon implanted with 150‐keV argon ions to doses ≳1017 ions/cm2 has been observed, in addition to an amorphous center, in the course of our investigations of amorphous Si layers damaged by ion implantation, when Ar+ implantation dose is more than about 10 times the critical dose for amorphization. These heavily argon‐implanted layers of silicon were characterized using ESR and ESCA. The structure of these layers was identified using transmission electron microscopy. It is found that the new ESR center in heavily implanted layers is due to amorphous SiC.

Two cases of reconstruction of postoperative defects of the mandible, mouth floor and tongue with the free radial forearm flap are presented. The patients were 63-and 61-yearold females.Both cases had advanced squamous cell carcinoma of the gum extending to the mouth floor and tongue (T4N1M0).Their postoperative courses were uneventful and the only postoperative complication was paresthesia around the anatomical snuffbox of the hand.The free radial forearm flap is thin and pliable, therefore postoperative recovery of function and shape are satisfactory. This flap seems to offer great versatility and wide possibilities of application. The long and large vessel pedicles make anastomosis simple and reliable. Consequently we consider the free radial forearm flap to be excellent for intra-oral reconstruction.

Three patients reconstructed with free radial forearm flap following hemiglossectomy are presented. The postoperative complications were only paresthesia of the snuff box, and the function of the recipient sites were satisfactory in all cases.This flap was proved to offer not only the thin and pliable skin for intraoral reconstruction, but also longer and larger vessels for vascular anastomosis. The versatility and advantages of the forearm flap are reviewed and discussed.

It is well-known that unsuccessful dental implants sometimes give rise to pronounced inflammatory bone resorption of the upper and lower jaw, and that in such cases it is practically much difficult to attain adequate prosthodontic rehabilitation after removal of the implants. On this study it is completely reported that two patients suffering from implant-induced osteomyelitis could be finely compensated for with the removable partial dentures using telescopic crowns after removal of the implants, and then the results are shortly discussed from the view of pathology, oral surgery and prosthodontics. In the first case a 52-year-old woman had been suffering from osteomyelitis of the right mandible due to the both bladevent and endodontic-endosseous implant, and in another case a 43-year-old woman had been suffering from osteomyelitis of the right maxilla due to the endosseous subperiosteal implant, and they had borne insufficient mastication on the affected side of the jaws. Several months after removal of the unsuccessful dental implants, they were rehabilitated with the removable partial dentures using telescopic crowns to recover and maintain good functions such as occlusion, mastication, cosmetics and speech, and oral and general health.

The method of intraoral oblique sagittal splitting oseotomy, a new modification of the sagittal splitting osteotomy, is presented. This procedure is distinct from Obwegeser-Dal Pont method in the following two points; 1. Horizontal osseous incision is made through the cortex medially, extending just only posterior and superior to the lingula. 2. Lateral bone cut is performed down the anterir border of the ascending ramus along the external oblique ridge directly to the inferior border of the mandible with slight oblique direction to the sagittal plane, not extending to the second molar.Thirty-two mandibular prognathism patients with or without anterior open bite have been corrected by this procedure. The advantages of this technique are reduction of operating time, less blood loss and fewer complications. This osteotomy is indicatd for mandibular prognathism with less than 15mm set back required.

This paper describes a case of bilateral Warthin's tumors of the parotid glands associated with amelanotic malignant melanoma of the maxillary gums in a 66-year-old man. The patient twice underwent neck dissection for his malignant melanoma. Although these Warthin's tumors were clinically asymptomatic, histological examination revealed them in the parotid regions of the dissected tissue. Clinical features and incidentally detected cases of Warthin's tumor are discussed.

The relation between the surgical excisions or operation methods and speech intelligibility was investigated on 22 glossectomees (11 underwent direct suture, 4 received split-skin grafts and 7 received reconstruction with the free radial forearm flap).Articultory function after glossectomy was assessed mainly by using 100 Japanese syllable speech intelligibility test.Our results are summarized as follows;1. Speech intelligibility after glossectomy is related to the extent of resected tongue tissue.2. According to glossal sounds, subjects with more than half of the tongue resected showed low intelligibility scores for sounds produced with the rear portion of the tongue.3. The glossectomees showed improvement in speech intelligibility for about six months after their operation, reaching a plateau thereafter. According to glossal sounds, speech intelligibility of the sounds produced with the rear portion of the tongue showed remarkable improvement.4. Comparing the surgical methods among subjects with the same extent of resection, higher speech intelligibility was observed in those treated with split-skin graft and free radial forearm flap reconstruction than in those treated by direct suture.5. Free radial forearm flap reconstruction has the advantage of high speech intelligibility scores for the sounds produced with the rear portion of the tongue and for plosive sounds.6. Articulatory function after glossectomy was observed to be influenced more by flexibility of the remaining tongue tissue than by its volume. Therefore, operation methods of preserving the tip of the tongue and conserving the mobility of the rear portion of the tongue should be selected for minimizing post glossectomy speech disorders.

Two patients recieved subtotal resection of floor and mandible, including radical neck dissection, because of advanced cancer of mandibular gum. Hemiglossectomy was done in one patients, and one-third of tongue was resected in the other.Both glossectomies were performed in the frontal direction. Immediate reconstruction proceeded using A-O plate and free radial forearm flap.The kinetics of the repaired tongues were analysed longitudinally with lateral cephalograms enhancing the tongue, ultrasonic scanner and speech intelligibility test of Japanese syllables (dividing the tongue into anterior, middle and posterior portions).As a results, the area of difficulty in postoperative movement of the tongue was wider than the resected portion in both patients. Longitudinally the kinetics remained stable more than 6 months after surgery.The mobility of the reconstructed tongue was thought to improve by six months after operation. But compensatory function was considered effective to compensate the deficiency of the tongue function.

Two cases of reconstructed oropharyngeal defect with free radial forearm flap are presented. Two male patients of forty-six and fifty-one years of age had wide resection including radical neck dissection for advanced squamous cell carcinoma (T4 Ni MO), in the left retromolar trigone in one case, and in the right buccal mucosa in the other. Both patients received surgical reconstruction using the forearm flap in the large defect of the oropharynx and oral mucosa. Their postoperative courses were uneventful, except for slight paresthesia in the anatomical “snuff box” of the hand. Local recurrence and metastasis have not appeared as of 13 and 12 months respectively after operation. Postoperative speech function and velopharyngeal closure are satisfactory in both cases. Consequently, the free radial forearm flap is considered to be suitable and functional for treating oropharyngeal defects in which rehabilitation with conventional flaps or maxillomandibular prosthesis is difficult.

This study was carried out to investigate the histological characteristics of the soft palate in three patients with congenital velopharyngeal incompetence. These patients were diagnosed as type Ia congenital velopharyngeal incompetence classified by cephalometric radiography with contrast media. The tissues examined consisted of the medial zone of the soft palate excised from the three patients and seven normal cadavers. These specimens were sectioned successively at two-or three-millimeter intervals on the frontal direction. The medial zone of the soft palate in all patients were noted macroscopically to be thinner than those of the control group. Histologically, fewer muscle fibers, more fibrosis of the interstitum and misdirection of fibers were found to varying degrees in the three patients compared with the normal cadavers.