Histopathology of ameloblastoma of the jaws; some critical observations based on a 40 years single institution experience

The aim of the present study is to examine all cases of intraosseous benign ameloblastomas treated between 1970 and 2010 in a single institution and to look for a possible correlation between the histopathological aspects and the demographical and clinical parameters, as well as the treatment outcome. The data of a total number of 44 patients were retrieved from the records. Nine patients were excluded because of doubt about the correct diagnosis (8 patients) or because of an extra-osseous presentation (1 patient). No statistically significant differences were found between the histopathological (sub)types of ameloblastomas and the demographical and clinical parameters, nor between the histopathological (sub)types and treatment outcome. Of the 28 patients treated by enucleation, in 17 patients one or more recurrences occurred, with no significant predilection for any histopathological (sub)type, including the unicystic type. There were no significant differences in the recurrence rate after enucleation in patients below and above the age of 20 years either. In six out of 17 patients with a recurrence, the recurrent lesion showed a different histopathological subtype than was encountered in the primary. In two cases a change from solid/multicystic to desmoplastic ameloblastomas was noticed. In conclusion, the current histopathological classification of benign intraosseous ameloblastoma does not seem to have clinical relevance with the possible exception of the luminal unicystic ameloblastoma that has been removed in toto, unfragmented. Since no primary desmoplastic ameloblastomas were encountered in the present study no further comments can be made on this apparently rare entity. © Medicina Oral S. L

A comparison of plant form and browsing height selection of four small stock breeds - Preliminary results

A direct observation technique was used to establish the foraging behaviour of Boer goats, Nguni goats, Pedi sheep and Dorper sheep. According to the Chi-square dissimilarity measure, plant-form (grass, forb, woody) differences between the diets of goats and sheep were greater than differences between the goat breeds and sheep breeds. The results from this study confirm that goats and sheep exhibit different foraging strategies. Sheep tend to forage more frequently from the herbaceous layer compared to goats, which also browse substantially from woody plants. Both goats and sheep increase their relative intake of woody plant products in winter. Goats tend to increase their woody browsing height in winter, probably adapting their foraging behaviour to fit differences in the canopy structures of prominent summer and winter forage species. Further research should be conducted to determine whether subtle differences in the foraging habits of different goat and sheep breeds exist