Local and systemic risk factors influencing the long-term success of angular stable alloplastic reconstruction plates of the mandible.

INTRODUCTION: After ablative surgery of the mandible, angular stable alloplastic reconstruction plates are commonly employed. The aim of the study was a long-term evaluation of local anatomical, as looking at systemic factors influencing specific complications and the failure rate of such plates. MATERIALS AND METHODS: In a retrospective study covering an 11-year period, we reviewed the outcomes of angular stable plates of patients who had a segmental resection of the mandible and subsequent alloplastic reconstruction. Complications and failure rates were assessed and local (anatomical size and localization of resection) as well as systemic risk factors (age, sex, radiation therapy, smoking) evaluated. RESULTS: Altogether, 162 plates were reviewed. The overall complication rate was 28% (fractures n = 8, loose screws n = 7, dehiscences n = 31) after an average time of 13 months. Cumulative survival rates of 73% after one, of 67% after 2, of 59% after 3 and of 40% after five years were observed. We found a significant correlation of increasing defect sizes to a rising complication and failure rate. Plate dehiscence occurred more often in defects including the midline (p = 0.005). Though not statistically significant, the occurrence of plate fracture was associated with lateral mandibular defects (7/8, p = 0.113). In smoking patients an earlier failure rate was seen. CONCLUSION: The results clearly indicate that the success of alloplastic reconstruction plates of the mandible is dependent on various risk factors. They should--if possible--be used temporarily only. If not done primarily, a secondary approach with bone reconstruction is recommended.

Short communication: Kelp taste preferences by dairy calves.

Kelp is a common feed additive used on many dairy farms in the United States. However, few data are available supporting the efficacy of its addition to cattle feed. The purpose of this study was to evaluate the taste preferences of calves provided with 0, 30, or 60 g of kelp daily in a sequential elimination experiment. Calves in this study always ranked the control treatment first when given a choice and consumed 34.5% more dry matter from the control treatment in the first 3-d segment of the experiment. During the second feeding segment (d 4 and 5), when the control treatment was removed, daily dry matter consumption was reduced in 4 out of 6 calves compared with control calves when this treatment was available (first feeding segment). However, calves did not differentiate between the 2 amounts of kelp. Results indicated that calves preferred calf starter grains without kelp.

Morphometric partitioning of respiratory surfaces in amphioxus (Branchiostoma lanceolatum Pallas).

The anatomical diffusing factors (ADFs), defined as the ratio of surface area to the thickness of the diffusion barrier, of possible respiratory surfaces of adult amphioxus (Branchiostoma lanceolatum) were evaluated using stereological methods. The ADF is greatest for the lining of the atrium and for the skin covering the segmental muscles. Calculation of the diffusing capacities for O(2) revealed that the lining of the atrium makes up nearly 83 % of the entire diffusing capacity (8.86 x 10(-3) microl min(-1)mg(-1)kPa(-1) while the skin over the segmental muscles (9%), the skin over the metapleural fold (4%) and the gill bars (4%) are of minor importance. The diffusing capacity of surfaces lying over coelomic cavities makes up 76% of the whole diffusing capacity, which is consistent with the hypothesis that the coelom may function as a circulatory system for respiratory gases. Muscles have approximately 23% of the entire diffusing capacity, indicating that they may be self-sufficient for O(2) uptake. The diffusing capacity of the blood vessels in the gill bars is only 1% of the total. Thus, the 'gills' lack significant function as respiratory organs in amphioxus (lancelets).

The effect of micronised nitroscanate on Echinococcus granulosus and Taenia hydatigena infections in dogs.

Trials with micronised nitroscanate carried out on 170 dogs infected with either Echinococcus granulosus or Taenia hydatigena indicated that a single treatment at 62-5 mg/kg and 16 mg/kg respectively significantly reduced the proportion of dogs infected with tapeworms. Some evidence is presented that micronisation may give a fourfold increase in the efficiency of nitroscanate in worm removal without increasing the toxic effects to the dog.