Construction and promotion of prosthodontics based on health sciences: for the achievement of a long life and good health cultivated by occlusion and mastication

Prosthodontics is a practical science based on life sciences and health sciences, and takes a role to contribute to the improvement of people's health and welfare. It is true the main field of prosthodontics and/or prosthodontic treatments is oral rehabilitation including recoveries of morphological defects and the functional disability caused by teeth loss. From this point of view, I am sure that the ultimate target of prosthodontics and/or prosthodontic treatments is maintenance and improvement of patient's QOL. To achieve this purpose, I think research, education, and clinical practice to be inseparable and integral in prosthodontics. This ensures that prosthodontics become more academic which can contribute to the society more greatly. Advertisement disclosure of "Prosthodontic Specialist certified by Japan Prosthodontic Society" is our earnest wish. The specialist system is regarded to be effective for the improvement of the medical treatment level, the information provision to the patient, and the promotion of cooperation hospital and clinic. On the other hand, the high quality treatments are severely requested and the specialists are strictly evaluated by the many people more than before. We have to be aware of our responsibility as Prosthodontic Specialists. In addition, Japan Prosthodontic Society is a corporate judicial person, and there is obligation and a responsibility that transmit necessary information to the society certainly and promptly, and present various proposals based on EBM as the opinion leader. Concretely, it is necessary to promote basic researches as well as clinical researches on prosthodontic treatments, and to examine the improvement of educational methods of prosthodontics. Let's reconfirm the purpose of our Society written in the article of incorporation and make an effort to achieve this purpose!     

The correlation of histologic features with a panoramic radiography pattern and a computed tomography pattern of bone destruction in carcinoma of the mandibular gingiva

OBJECTIVE: We sought to clarify the correlation among a computed tomography (CT) or a panoramic radiography (PR) pattern of bone destruction, a histologic pattern of bone destruction, and a mode of invasion in carcinoma of the mandibular gingiva. STUDY DESIGN: CT images, panoramic radiographs, and decalcified, hematoxylin-eosin-stained preparations of the excised mandibular bone of 62 patients with carcinoma of the mandibular gingiva were retrospectively evaluated. Each computed tomograph, panoramic radiograph, and the histologic pattern of bone destruction was classified as 1 of 5 types: erosive, erosive and partly mixed, mixed, mixed and partly invasive, or invasive. The mode of invasion of the tumor was also assessed with a hematoxylin-eosin-stained preparation of the initial biopsy specimen. The relationships among the CT pattern, the PR pattern, the histologic pattern of bone destruction, and the mode of invasion of the tumor were statistically analyzed by using the Spearman rank correlation test. RESULTS: The CT pattern (P =.005) and the PR pattern (P =.003) were significantly correlated with the histologic pattern with respect to the bone destruction. The CT pattern (P =.996), the PR pattern (P =.997), and the histologic pattern (P =.521) of bone destruction were not correlated with the mode of invasion seen in the biopsy specimen. CONCLUSION: The CT pattern and the PR pattern of bone destruction reflect the histologic pattern of bone destruction caused by carcinoma of the mandibular gingiva but are not associated with the mode of invasion of the tumor.     

鼠半胱氨酸蛋白酶抑制物cystatin S 对人口腔牙龈卟啉菌生长的抑制

目的：观察鼠半胱氨酸蛋白酶抑制物ｃｙｓｔａｔｉｎＳ对人口腔牙龈卟啉菌（Ｐｏｒｐｈｙｒｏｍｏｎａｓｇｉｎｇｉｖａｌｉｓ）生长的影响。方法：用琼脂扩散法检查了ｃｙｓｔａｔｉｎＳ对人口腔数种牙龈卟啉菌生长的抑制情况。结果：虽然对不同菌株其影响程度略有差异，对实验用牙龈卟啉菌３８１，３８１Ｐ，ＡＴＣＣＷ５０，Ｗ８３，３３２７７，ＮＣＴＣ１１８３４，ＶＰＩ１４０１８生长均有抑制作用，并且具有药物浓度依赖性。结论：鼠半胱氨酸蛋白酶抑制物ｃｙｓｔａｔｉｎＳ对人口腔牙龈卟啉菌生长有抑制作用。     

Ultrasound observations of tongue motor behavior

In this investigation of motor skills of the tongue and age-related changes in motor behavior, upward and downward tongue movements with the teeth in centric occlusion and regulated by a metronome were recorded. The recordings were made by use of ultrasound diagnostic equipment with a 5 MHz electronic convex section scanning probe and a physiologic signal unit connected to a heart sound microphone in a group of young subjects and a group of older subjects. The results were as follows. (1) The system provided a useful method to evaluate motor skills of the tongue with sound signals showing clear images of the tongue surface and its movements. (2) The rhythm of tongue movements in older persons varied more than in younger persons. (3) The velocity in the upward and downward movements decreased and were statistically significant (p less than 0.01) in the older group. (4) The time lag between the sound signal and the start of touching the palate and floor of the mouth was longer (p less than 0.01) and the variations were greater in the older group. (5) The study showed age-related changes in motor behavior of the tongue.     

Gingival tissue-produced inhibition of platelet aggregation and the loss of inhibition in streptozotocin-induced diabetic rats

Addition of medium incubated with normal rat gingival tissue to platelet-rich plasma inhibited ADP-induced platelet aggregation. The ability of rat gingiva to produce activity inhibiting platelet aggregation was enhanced by the addition of arachidonic acid. Diabetic rat gingiva failed to inhibit platelet aggregation but did produce the anti-platelet aggregating activity in the presence of arachidonic acid. Indomethacin blocked the production of anti-platelet aggregating activity. There was no difference in conversion of [1-¹⁴C]arachidonic acid to prostaglandins by normal and diabetic rat gingiva. These results suggest that an arachidonic acid metabolite released from gingiva during incubation inhibits platelet aggregation, and the synthesis of the metabolite is impaired in diabetic rat gingiva. A decrease in availability of arachidonic acid may be a causal factor of the defect in diabetic rat gingiva.     

Cellular compatibility of a gamma-irradiated modified siloxane-poly(lactic acid)-calcium carbonate hybrid membrane for guided bone regeneration

A bi-layered silicon-releasable membrane consisting of a siloxane-poly(lactic acid) (PLA)-vaterite hybrid material (Si-PVH) microfiber mesh and a PLA microfiber mesh has been developed by an electrospinning method for guided bone regeneration (GBR) application. The bi-layered membrane was modified to a three-laminar structure by sandwiching an additional PLA microfiber mesh between the Si-PVH and PLA microfiber meshes (Si-PVH/PLA membrane). In this study, the influence of gamma irradiation, used for sterilization, on biological properties of the Si-PVH/PLA membrane was evaluated with osteoblasts and fibroblasts. After gamma irradiation, while the average molecular weight of the Si-PVH/PLA membrane decreased, the Si-PVH/PLA membrane promoted cell proliferation and differentiation (alkaline phosphatase activity and calcification) of osteoblasts, compared with the poly(lactide-co-glycolide) membrane. These results suggest that the gamma-irradiated Si-PVH/PLA membrane is biocompatible with both fibroblasts and osteoblasts, and may have an application for GBR.     

Middle-preserving pancreatectomy with reversed pancreaticogastrostomy: report of a case

Parenchyma-sparing pancreatic resections have been reported increasingly in recent years; however, for multifocal diseases involving the head and the tail of the pancreas, total pancreatectomy is still the preferred procedure. The possible consequence of this procedure is loss of normal pancreatic parenchyma, resulting in insufficiency of pancreatic exocrine and endocrine functions. Various types of limited resection have been introduced for isolated or multiple pancreatic lesions, depending on the location of the tumor. Even for multifocal diseases, if the pancreatic body is spared, a middle-preserving pancreatectomy (MPP) can be performed to assure maximal pancreatic function and uncompromised quality of life. Yet, few papers have introduced the feasibility of MPP for a better outcome. This report describes a new surgical technique for MPP using an alternative approach for the remnant pancreas anastomosis. We used this technique successfully to remove a bifocal neoplasm: adenocarcinoma of the distal bile duct and mucinous cyst adenoma in the tail of the pancreas.