[Relationship between red blood cell transfusion volume and posttransfusional iron overload in hematological diseases].

We retrospectively investigated the status of transfusional iron overload at Kinki University Hospital. One hundred and sixty three patients received more than 10 red blood cell (RBC) units per year in 2009 and 2010. Myelodysplastic syndrome (37.4%) and aplastic anemia (11.0%) accounted for about 50% of the underlying diseases. At the time of receiving a total of 20 RBC units, 90.8% and 66.2% of the 65 patients evaluated had more than 500 and 1,000 ng/ml of serum ferritin, respectively. The frequency of organ dysfunction associated with iron overload was 56.9% of all the patients assessed, 37.8% of patients with serum ferritin levels of 500∼999 ng/ml, and 67.4% of patients with serum ferritin levels >1,000 ng/ml. Although the Japanese guidelines propose 40 units of RBC transfusion and/or a serum ferritin level of 1,000 ng/ml as a good point to start iron chelation therapy, our results suggest that iron overload and consequent organ dysfunction may occur earlier than this. Therefore, it may be necessary to start iron chelation therapy earlier than that suggested by the Japanese guidelines.

Quantitative measurement of marginal disintegration of ceramic inlays.

The objectives of this study include establishing a method for quantitative measurement of marginal change in ceramic inlays and clarifying their marginal disintegration in vivo. An accurate CCD optical laser scanner system was used for morphological measurement of the marginal change of ceramic inlays. The accuracy of the CCD measurement was assessed by comparing it with microscopic measurement. Replicas of 15 premolars restored with Class II ceramic inlays at the time of placement and eight years after restoration were used for morphological measurement by means of the CCD laser scanner system. Occlusal surfaces of the restored teeth were scanned and cross-sections of marginal areas were computed with software. Marginal change was defined as the area enclosed by two profiles obtained by superimposing two cross-sections of the same location at two different times and expressing the maximum depth and mean area of the area enclosed. The accuracy of this method of measurement was 4.3 +/- 3.2 microm in distance and 2.0 +/- 0.6% in area. Quantitative marginal changes for the eight-year period were 10 x 10 microm in depth and 50 x 10(3) microm2 in area at the functional cusp area and 7 x 10 microm in depth and 28 x 10(3) microm2 in area at the non-functional cusp area. Marginal disintegration at the functional cusp area was significantly greater than at the non-functional cusp area (Wilcoxon signed-ranks test, p < 0.05). This study constitutes a quantitative measurement of in vivo deterioration in marginal adaptation of ceramic inlays and indicates that occlusal force may accelerate marginal disintegration.