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Objectives

The generic substitution of medicines has been introduced in Europe since the 1990s to increase price competition and the use of cheaper equivalents. Patent expiry is assumed to be associated with changes in sales patterns, particularly when combined with generic substitution. Other changes have been observed when prescribers obtain new information on drug safety and efficacy of medicines. This article examines to what extent patent expiry and new medical information on efficacy influence the pharmaceutical sales patterns of antihypertensive medicines in Japan and Sweden.

Methods

Angiotensin-converting enzyme inhibitors and angiotensin Ⅱ antagonists (ARBs) were selected, since they are widely used in both Japan and Sweden. The two analysed interventions were patent expiry and published information on lower efficacy for two ARBs. Seasonal autoregressive integrated moving average modelling with intervention was used to analyse changes in sales volumes.

Results

Patent expiry was not associated with any significant changes in sales patterns. In Sweden, the sales rate of losartan increased following new information on lower efficacy for candesartan and telmisartan (0.77650 DDDs/1,000 inhabitants per day, p?=?0.0068), whereas candesartan sales decreased (-0.50760 DDDs/1000 inhabitants per day, p?=?0.0058). In Japan, the publication of new efficacy information was also associated with a significant decrease in candesartan (?1.21215 DDDs/1000 inhabitants per day, p?=?0.001).

Conclusions

We found sales patterns of antihypertensive medicines were to a large extent affected by information on efficacy rather than patent expiry. However, further assessment is needed for other medicine groups and settings. (248 words)  相似文献   
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Our aim was to find out whether the quality of bone around the inferior alveolar nerve is correlated with neurosensory disturbance to the nerve after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Computed tomograms (CT) were taken of 35 patients with mandibular prognathism and 35 without. To assess the density of bone around the inferior alveolar nerve, the width of the buccal cortical bone in the mandibular second molar regions was measured on CT. The Hounsfield units (HU) in the same regions were also measured. The number of HU in the mandible around the second molar regions was significantly higher (p < 0.01) in those with neurosensory disturbance (p < 0.01). The quality of bone measured by HU is associated with an increased risk of neurosensory disturbance, but the width of buccal bone is not.  相似文献   
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OBJECTIVES: To visualize articulatory movement using a magnetic resonance imaging (MRI) movie of a subject with cleft lip and palate (clp) and to demonstrate the usefulness of this method for studying oropharyngeal function. MATERIAL AND METHODS: Dynamic changes in oropharyngeal structures were assessed with an MRI movie of a man with cleft lip and palate and in a normal adult male volunteer during the articulation of /pa/, /ta/, and /ka/. RESULTS AND CONCLUSIONS: Different movement patterns were observed during articulation in the subject with CLP compared with the normal volunteer. Posterosuperior movement of the tongue and the anterior movement of the posterior pharyngeal wall were clearly visualized in the subject with CLP. Thus, MRI movies appear to be a promising tool for evaluating speech function in patients with CLP because of their noninvasive and nonradiation nature.  相似文献   
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Purpose

To investigate the influence of firing condition and thickness of a yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) frame on the fracture toughness of veneering ceramics.

Methods

Layering and pressable ceramics without frames or on 0.8- and 1.2-mm-thick Y-TZP frames were fired with 5 schedules (normal and 4 customized conditions). The fracture toughness of the ceramics was measured at 0.5–2.5 mm from the frame by the indentation fracture method. Crystal structures at the measurement points were evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Results

Under customized firing conditions, the fracture toughness of the layering ceramic significantly decreased, particularly near the frame. Use of a 1.2-mm-thick frame significantly decreased the fracture toughness of both layering and pressable ceramics compared to ceramics without the frame. The decreased fracture toughness only occurred close (0.5 and 1.0 mm) to the frame. XRD analysis showed identical diffraction patterns between points near and far from the frame, suggesting that the decreased fracture toughness was not due to crystal defects or impurities. SEM revealed many microcracks and large crystals in layering ceramic near the 1.2-mm-thick frame, possibly resulting from the thermal properties of the zirconia frame, such as large heat capacity and low thermal conductivity.

Conclusions

Modification of the firing conditions from the manufacturer’s instructions and inclusion of a thick Y-TZP frame decreased the fracture toughness of veneering ceramics at the interface, suggesting that a thick frame would pose a potent fracture risk in veneering ceramics used for zirconia-based all-ceramic restorations.  相似文献   
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This clinical article describes a case of dental rehabilitation using an implant-carrying plate system (EPITEC) for a patient with severely resorbed edentulous maxilla and microstomia. In this case, the presence of microstomia prevented bone augmentation procedures through an intraoral approach. Treatment using 2 endosseous implants inserted in the canine regions and an implant-supported overdenture was planned. However, endosseous implants were not feasible on the right side because of insufficient available bone volume. An implant-carrying plate system was then utilized on the right side. Four months later, an implant-supported ball-attachment overdenture was fabricated. At the 2-year follow-up, the clinical course remained uneventful, and the patient remained satisfied with the treatment.  相似文献   
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