Cost-Effectiveness Analysis of Perioperative Oral Management after Cancer Surgery and an Examination of the Reduction in Medical Costs Thereafter: A Multicenter Study.

In April 2012, perioperative oral management (POM) was approved for inclusion in the national health insurance system of Japan to prevent the occurrence of pneumonia, a major complication in cancer patients. The subsequent decrease in the incidence of postoperative pneumonia indicated the prophylactic effect of POM. The constant increase in health expenditure necessitates a cost-effectiveness analysis. In addition, the effect of reducing healthcare costs owing to health technologies must be evaluated. In the present multi-institutional study, the cost-effectiveness analysis of POM was conducted by comparing the incidence of postoperative pneumonia and the healthcare costs between patients who received surgery for malignant tumors before (n = 11,886) and after (n = 13,668) the introduction of POM. Additionally, the effect of reducing healthcare costs was evaluated. Reductions in the number of patients who developed pneumonia, duration of hospitalization, and number of deaths were observed after the introduction of POM. The incremental cost-effectiveness ratio was 111,927 yen, hence the prevention of postoperative pneumonia needs 111,927 yen per patient in healthcare costs. Consequently, a maximum reduction of 250,368,129 yen in healthcare costs was observed between the incremental costs for pneumonia treatment and the cost of POM. These findings indicate that improvements in cost-effectiveness can be expected in the future through the development of procedure and system for POM.

Pneumonia prevention effects of perioperative oral management in approximately 25,000 patients following cancer surgery.

AIM: We conducted a multicenter study to explore the risk factors of developing pneumonia and the effectiveness of perioperative oral management (POM) for the prevention of pneumonia in postsurgical patients. METHODS AND RESULTS: A survey covering eight regional hospitals was conducted over 4 years, from April 2010 to March 2014. Using the Diagnosis Procedure Combination database, a target group of 25,554 patients with cancer who underwent surgery was selected and assessed from a population of 346,563 patients without pneumonia on admission (sample population). The study compared the incidence of pneumonia and attempted to identify the significant predictive factors for its occurrence in these patients using multiple logistic regression analysis. Comparative assessment for the occurrence of pneumonia before and after POM implementation showed a significant incidence decrease after POM introduction in the target group, with no such change observed in the sample population. Multiple logistic regression analysis showed that the odds ratio for pneumonia occurrence after POM introduction was 0.44, indicating a reduced risk of pneumonia. CONCLUSION: POM in cancer patients was indeed effective in reducing the incidence of pneumonia in hospitals and thereby helped in preventing pneumonia during hospitalization.

Comparative sequential morphological analyses during in vitro chondrogenesis and osteogenesis of mesenchymal stem cells embedded in collagen gels.

Chondrogenesis and osteogenesis during fetal development and postnatal growth constitute one of the most interesting and complicated subjects in biology. In this study, bone marrow mesenchymal stem cells (MSCs) were embedded in collagen gel, cultured in chondrogenic or osteogenic medium, and compared morphologically during chondrogenic and osteogenic differentiation sequentially by light and electron microscopy and immunohistochemical examination. Before induction, the MSCs were dispersed and round in the collagen gel. At day 1, MSCs with a large number of short processes produced extracellular fibers whose immunoreactivity was positive for collagen type I. At day 3, the shape of MSCs changed from round to elongated. Gap junctions positive for connexin 43 were also observed. At day 7, remarkable morphological differences were first observed during chondrogenesis and osteogenesis. The shape of MSCs changed to polygonal without cell processes during chondrogenesis, while MSCs remained spindle shaped with long processes during osteogenesis. Concurrently, collagen type II during chondrogenesis and osteocalcin during osteogenesis were first detected. At day 21, chondrogenesis and osteogenesis of the MSC/collagen composite further progressed, respectively. In vitro chondrogenesis and osteogenesis using an MSC/collagen composite clarified the morphological differences.

A simple method of fabricating an interim obturator prosthesis by duplicating the existing teeth and palatal form.

An interim obturator prosthesis is required for the restoration of speech, deglutition, and improvement of esthetics after maxillectomy. This article describes a simple method for fabricating the interim obturator prosthesis by duplicating the patient's teeth and palate. The interim obturator prosthesis fabricated by duplication of the presurgical appearance and contour may be more acceptable to the patient.

Lip plumper prosthesis for a patient with a marginal mandibulectomy: a clinical report.

An intraoral prosthesis was fabricated to restore more normal contour to a patient's lower lip that was compromised following a marginal mandibulectomy performed to eradicate a malignant neoplasm. The surgical resection compromised the lower lip on the affected side because the marginal mandibular branch of the facial nerve was damaged during the surgical resection. The prosthesis successfully restored the lost lip support, reduced the incidence of lip biting, and improved the patient's oral competency. This clinical report describes the procedure for making an intraoral lip plumper prosthesis to improve patient esthetics and oral function.

Innovative gas injection technique for closed-hollow obturator.

PURPOSE: The purpose of this study was to determine the proper prerequisite conditions for gas injection and the steps for applying gas injection for obturator fabrication. MATERIALS AND METHODS: Optimal prerequisite conditions were investigated by using thermocoupling to verify exothermic changes in the resin during polymerization. Three experimental groups were designated: in the control group (C), resin was packed into the mold without argon gas injection; in the gas injection group (GI), after resin packing, gas was injected into the resin bulb in the mold; and in the plunger/gas injection group (PGI), after resin packing, the syringe plunger was drawn out before gas injection. RESULTS: The 55 degrees C mold temperature and addition of 0.3% DMPT to the monomer liquid caused differences in exothermic temperature increase in various parts of the resin. Without gas injection and plunger drawing, porosity was observed in the thick bulbs of groups C and PGI. In group PGI, a balloon-like elliptic hollow was observed. Compared to group C, the weight reduction in group PGI was approximately 10%. CONCLUSION: Proper mold temperature with secondary venting and the addition of DMPT were required before the injection of gas. The resulting prosthesis could be fabricated in one step and required no resin seal.

Chairside modification of a surgical obturator: a clinical report.

Functional rehabilitation of maxillectomy patients is important in reestablishing the patients' quality of life. This article describes a prosthodontic technique that allows for modification of a surgical obturator clinically, allowing rapid restoration of speech and deglutition.

The pattern of tongue pressure against the palate during articulating glossal sounds in normal subjects and glossectomy patients.

The purpose of the present study was to measure tongue pressure with the aim of characterizing the pattern of linguopalatal contact during articulating glossal sounds in normal subjects and glossectomy patients. Tongue pressures against the palate were evaluated in 13 normal subjects and 5 glossectomy patients by using three parameters: the duration from the onset of linguopalatal contact to the time of maximum pressure, the maximum pressure, and anterior posterior ratio of the maximum pressure. Three glossal sounds, [ti], [t [symbol: see text] i], and [[symbol: see text] i], which have tendency of mishearing in glossectomy patients, were selected for test sounds. A unique characteristic was demonstrated in normal subjects. The score of the maximum pressure showed an apparent order among the three sounds, while the durations revealed the opposite order. Anterior posterior ratio of the maximum pressure also showed some relationship among three sounds. In glossectomy patients, these characters were not found. The loss of tongue volume or deterioration of tongue mobility causes these results.

Electromyographic activity of masticatory muscles and mandibular movement during function in marginal mandibulectomy patients.

The purpose of this study is to evaluate the masticatory muscle activity and mandibular movement during function in marginal mandibulectomy patients. Three marginal mandibulectomy patients and three healthy subjects participated in this study. The activities of the temporalis (TA) and masseter muscles (MM) on the normal and resected sides during maximum voluntary clenching (MVC) and gum chewing (Gch), and mandibular movement during Gch were analyzed. Paired t-test, Student's t-test and one-way ANOVA were performed at P < 0.05. For MVC, integrated EMG (iEMG) in patients was lower than in healthy subjects. When iEMG of each muscle activity in patients was compared, TA activity on the resected side was greater than that of MM. There were no differences between the normal and resected sides in TA or MM. For Gch, no differences in iEMG, burst or chewing time were found between patients and healthy subjects. MVC was greater than Gch in healthy subjects, but no difference was found in patients. The range of mandibular movement along the X axis in patients was greater than in healthy subjects. Within the limitations of this study, EMG activity in patients during MVC was remarkably lower than that in healthy subjects, and altered mandibular movement was observed.

Vibration analysis of obturator prostheses with different bulb height designs.

The purpose of this study was to investigate the effect on the vibratory characteristics of a cast hollow obturator prosthesis retainer when varying its bulb height. Bulb parts with high (H), middle (M), and low (L) lateral walls were prepared. A Vibration Generator was used to excite the three obturators, while a Laser-Doppler Vibrometer was employed to detect the vibrations at specified measurement points. The frequency response functions of each obturator were recorded on an FFT analyzer to enable their modal shapes to be identified. In addition, transient response simulations were carried out and the decay rate (DR) and the maximum amplitude (MA) of the rest and clasp parts of each obturator were obtained. These were statistically analyzed by ANOVA and Fisher's PLSD test (p < 0.01). The modal shapes were almost the same in all obturators. Significant differences were found in DR in all pairs among the three obturator prostheses, with the DR of the L type being the highest. On the other hand, there were no significant differences in MA. We conclude that the L type is preferable from the standpoint of its vibratory characteristics.

High extracellular calcium affects osteoclastogenesis in mouse bone marrow cell culture.

The effects of high extracellular calcium (high Ca) in the local microenvironment on osteoclasts, osteoclast progenitors and stromal cells are not fully understood. We examined high Ca effect on osteoclastogenesis in mouse bone marrow cell culture. Mouse bone marrow cells were cultured for up to 6 days in the medium supplemented with 1, 25(OH)2 vitamin D3 (D3). High Ca treatment at the early stage of culture (the initial 24 hours) reduced the number of tartrate resistant acid phosphatase-positive multinuclear cells (TRAP(+)MNCs). This treatment slightly up-regulated the mRNA expressions of receptor activator of NF-(B ligand (RANKL), RANK and osteoprotegerin (OPG). This inhibitory effect on the formation of TRAP(+)MNCs was recovered by RANKL. In contrast, high Ca treatment at the later stage of osteoclastogenesis (the last 2 days of culture) stimulated the formation of TRAP(+)MNCs, increased RANKL and RANK mRNA expressions and decreased OPG mRNA. High Ca at neither the early nor the later stage of culture affected the total number of adherent cells and the mRNA expression of alkaline phosphatase and osteopontin. In conclusion, high Ca affects osteoclastogenesis in a manner depending on the stage of osteoclastogenesis, which is partly mediated via the RANKL-RANK-OPG regulatory system.