Elly S. Grossman

Atraumatic Restorative Treatment (ART): factors affecting success

The success of tooth restorations rendered according to principles of the Atraumatic Restorative Treatment (ART) approach is dependant on various clinical factors. The most common failures, due to these factors, are partial material loss; complete material loss; caries related to restoration margin and material wear > 0.5mm. The main reason for clinical ART failures are related to operator skills and performance. The prevention and management of ART failures includes emphasis on correct clinical indication and the repair of failed restorations. A new caries classification may provide guidance for clinical indication. The classification combines site and size of a lesion, which is reflected in a dual coding system. In addition, ART training and diligence during ART application are important for clinical success.

Features of central giant cell granuloma of the jaws xenografted in nude mice

In order that the growth pattern and histologic and ultrastructural differentiation of the central giant cell granuloma of the jaws be studied, tissue from three lesions was transplanted into nude mice. Xenografts were harvested at 3 weeks, 5 weeks, 8 weeks, and 13 weeks and examined histologically and ultrastructurally. Implants could be identified as firm subcutaneous nodules, but after 3 weeks began regressing. At 13 weeks, almost total regression had occurred. Histologically, grafts were well vascularized and there was no evidence of necrosis. Typical multinucleated giant cells disappeared at an early stage. The ultrastructural features of the grafts showed giant cells lying in close association with uninuclear cells, features suggestive of a fusion process. Many cells containing microfilaments at their periphery were identified in the original lesional tissue as well as in the xenografts. These cells strongly resembled myofibroblasts. Collagen bundles were seen within the cytoplasm of stromal cells. The observations suggest that the multinucleated giant cells represent a stimulus-dependent, differentiated end-stage cell population.

A study of the fine structure, enzyme activities and pattern of 14co2 incorporation of highveld grasses from different successional stages

A detailed study of selected grasses has been made with respect to fine structures characteristics, enzyme activities associated with C-4 and C-3 pathway photosynthesis, and short term carbon dioxide-14 incorporation experiments. A good correlation was obtained between the fine structure, the carbon pathway and the successional position of the grasses studied. Keywords: enzyme activities|patterns|highveld grasslands|grasses|successional stages|characteristics|C4 pathways|C3 pathways|photosynthesis|carbon dioxide|experiments|fine structures|carbon pathways|Transvaal|Highveld|Gauteng Province|compensation points