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Notes: Abstract: Due to lack of the periodontal ligament, osseointegrated implants, unlike natural teeth, react biomechanically in a different fashion to occlusal force. It is therefore believed that dental implants may be more prone to occlusal overloading, which is often regarded as one of the potential causes for peri-implant bone loss and failure of the implant/implant prosthesis. Overloading factors that may negatively influence on implant longevity include large cantilevers, parafunctions, improper occlusal designs, and premature contacts. Hence, it is important to control implant occlusion within physiologic limit and thus provide optimal implant load to ensure a long-term implant success. The purposes of this paper are to discuss the importance of implant occlusion for implant longevity and to provide clinical guidelines of optimal implant occlusion and possible solutions managing complications related to implant occlusion. It must be emphasized that currently there is no evidence-based, implant-specific concept of occlusion. Future studies in this area are needed to clarify the relationship between occlusion and implant success.

Notes: Abstract. It is particularly difficult to distinguish between early rejection and graft pancreatitis when early rejection produces an elevated serum amylase level. In this study we determined whether peripancreatic fluid cytology (PFC) can differentiate early acute rejection and graft pancreatitis as an alternative diagnostic tool to graft biopsy that has the potential of pancreatic fistula and hemorrhage. Sixty-two dogs received either a segmental pancreas allograft ( n = 25) or autograft ( n = 37) heterotopically in the neck. This study included five groups: allografts without immunosuppression (group A, n = 12), allografts with immunosuppression (group B, n = 13), autografts without immunosuppression (group C, n = 11), autografts with immunosuppression (group D, n = 12), and autografts treated by 45 minutes of pretransplant warm ischemia to induce acute graft pancreatitis (group E, n = 14). A closed suction drainage catheter was placed next to the graft to collect peripancreatic fluid daily after the transplant. PFC was performed using May-Gruenwald-Giemsa double-staining technique and compared to the corresponding histology through the observation period. In analyses of 50 functioning grafts, PFC performed on day 1 showed similar neutrophil accumulations in all groups. In sharp contrast, on days 3 and 6, group A had dramatically increased mononuclear cell concentrations in PFC, whereas groups B, C, and D showed significantly lower concentrations, the percent of mononuclear cells among total leukocytes being 47.3 ± 23.4%, 11.8 ± 4.9%, 4.3 ± 1.8%, and 6.4 ± 2.4% (day 3); and 32.7 ± 9.8%, 10.5 ± 4.8%, 7.2 ± 4.2%, and 8.6 ± 6.4% (day 6) in groups A, B, C, and D, respectively. On the other hand, in group E numerous degenerating neutrophils with a marked to moderate increase in necrotic tissue fragments were observed by PFC on days 3 and 6. In terms of graft histology on days 3 and 6, group A showed interstitial mononuclear cell infiltration indicating an acute rejection process, whereas groups B, C, and D had minimal inflammatory cell infiltration. In group E graft pancreatitis was histologically confirmed on days 3 and 6. These results suggest that PFC after pancreas transplantation could be a safe, simple, useful diagnostic tool for discriminating early graft rejection from graft pancreatitis.

Notes: Abstract. We have shown that 24-hour preservation by a two-layer [University of Wisconsin solution (UW)/perfluorochemical (PFC)] cold storage method at 4°C allowed tissue ATP synthesis and resuscitated canine pancreases subjected to 90 minutes of warm ischemia. The purpose of this study was to examine whether the two-layer (UW/PFC) mild hypothermic storage method at 20°C could shorten a preservation period for recovery of ischemically damaged pancreas and clarify changes of tissue adenine nucleotide metabolism and tissue perfusions. After 90 minutes of warm ischemia, canine pancreas grafts were preserved by the two-layer method and then autotransplanted. Tissue adenine nucleotide levels at the end of preservation and tissue perfusions after reperfusion were measured. Pancreas grafts subjected to 90 minutes of warm ischemia did not survive (0 of 5), without preservation. During a 5-hour preservation by the two-layer cold storage method the grafts did not synthesize enough ATP to repair damaged cell, although tissue perfusions were maintained after reperfusion. Consequently, ischemically damaged pancreases were not resuscitated (0 of 3). However, during 5-hour preservation by the two-layer mild hypothermic storage method, the grafts supplied enough ATP for processes that repair damaged cells, and tissue perfusions were maintained after reperfusion. As a result, ischemically damaged grafts were resuscitated (5 of 5). We conclude that 5-hour preservation by the two-layer mild hypothermic storage method accelerates ATP synthesis, which is essential for repairing damaged cells and protects the vascular microcirculation. This method can resuscitate ischemically damaged pancreas faster and holds promise for pancreas-kidney transplantation from cardiac arrest donors.