Assessment of the relationship between the upper and lower arch changes with the opening of the expanding screw after the rapid maxillary expansion

OBJECTIVE

The purpose of this study is to assess the relationship of the upper and lower arch dimension changes after the rapid maxillary expansion (RME) with the screw opening of the modified Hyrax® type appliance.

MATERIALS AND METHODS

Initial (T1) and final (T2) models of study of 63 children between 7 years and 6 months and 16 years and 5 months were performed. From these, 21 showed maxillary atresia and/ or posterior crossbite and were submitted to expansion and 42 children formed the control group .The appliance used in this work was the modified Hyrax appliance using the 7mm expanding screws "Dentarum". The measures of the upper intercanine and the upper and lower intermolar distances were performed in plaster models with the help of a digital paquimeter. The opening of the appliance's screw was also assessed.

RESULTS

The RME provoked a statistically significant increase in the upper interdental distances and no statistic significance in the lower interdental distances, i.e. the change in the 16 - 26, 13 - 23 and 36 - 46 distance was of 5,85 mm, 5,31 and 0,34 mm respectively. The average opening of the expander screw, which was of 6,27 mm.

CONCLUSION

The appliance's opening is related to the interdental distance changes, i.e. for each appliance's opening mm, a 0,94 variation in the upper intermolar distance, a 0,87 in the upper intercanine distance and 0,054 in the lower intermolar distance are provoked.

Perception of dental aesthetics in paediatric dentistry

AIM

Assessing the perception of the aesthetic components of the oral health by paediatric patients at different stages of the child psychological development of Piaget.

MATERIALS AND METHODS

Twenty children aged between 21 months and 11 years, of both sexes, patients of a private clinic, were selected. The present study group consisted of patients treated for oral pathologies. A set of similar supplies was given to all children and they were asked to do a drawing, whose theme was "beautiful teeth and ugly teeth". The drawings were evaluated according to the classification of the cognitive development of Piaget.

RESULTS

Children of all ages clearly represent their perception of what "beautiful teeth" and "ugly teeth" are. These representations provide the dental professional a clear vision of the child's feeling about dental aesthetics.

CONCLUSION

The drawings are a useful source of information for assessing the aesthetic perception of paediatric patients. The knowledge of the children's aesthetic perception is relevant to paediatric dentists because children are conscious about their dental aesthetic appearance and that of the other children.

Raf-induced transformation requires an interleukin 1 autocrine loop

The c-Raf-1 serine/threonine protein kinase plays a critical role in the proliferation of most cell types that have been examined. As such, the Raf proto-oncogene is thought to play a central role in the development of human tumors. Although the c-raf-1 gene itself rarely appears to be mutated in human tumors, the kinase activity of Raf is frequently found to be more active in tumor cells, likely through constitutive activation of upstream activators of Raf. The downstream events triggered by Raf that are involved in transformation have been studied less extensively. We show in this study that Raf-induced transformation of NIH 3T3 cells requires the activation of the ubiquitously expressed transcription factor, nuclear factor-kappaB, by Raf. Furthermore, through the use of CrmA, interleukin 1 (IL-1) receptor antagonist, and a dominant-negative form of TRAF6, we demonstrate a requirement for IL-1 production and signaling from the IL-1 receptor as necessary components of Raf-induced transformation. These results indicate that IL-1 may be used as an autocrine growth factor by a number of tumors in which activation of Raf plays an important role in transformation and suggest that blockade of IL-1 signaling may be an approach to limiting the growth of certain tumors.

A role for the Ral guanine nucleotide dissociation stimulator in mediating Ras-induced transformation

Oncogenic Ras transforms cells through the activation of multiple downstream pathways mediated by separate effector molecules, one of which is Raf. Here we report the identification of a second ras-binding protein that can induce cellular transformation in parallel with activation of the Raf/mitogen-activated protein kinase cascade. The Ral guanine nucleotide dissociation stimulator (RalGDS) was isolated from a screen for Ras-binding proteins that specifically interact with a Ras effector-loop mutant, ras(12V,37G), that uncouples Ras from activation of Raf1. RalGDS, like ras(12V, 37G), cooperates synergistically with mutationally activated Raf to induce foci of growth and morphologically transformed NIH 3T3 cells. RalGDS does not significantly enhance MAP kinase activation by activated Raf, suggesting that the cooperativity in focus formation is due to a distinct pathway acting downstream of Ras and parallel to Raf.

Haemorrhagic cystitis in paediatric bone marrow transplant patients: an association with infective agents, GVHD and prior cyclophosphamide

The frequency of haemorrhagic cystitis (HC) is evaluated in a paediatric population undergoing bone marrow transplantation (BMT) and its relationship to therapy with cyclophosphamide (CY) prior to conditioning for BMT (prior CY), infectious agents and graft-versus-host disease (GVHD) assessed. HC was defined as macroscopic haematuria with early onset HC occurring within 2 days of and delayed onset beyond 2 days from CY infusion. Sixty-three children received a total of 65 BMTs between July 1988 and January 1991, with 60 children receiving CY and 3 l/m2/24 h of post-hydration fluid post-CY as part of their conditioning. There were no cases of early onset HC. Eleven (17%) children had a total of 19 episodes of delayed onset HC. Overall, an infective agent was identified in the urine at the time of 17 of 19 (89%) episodes of HC. While papovavirus was the most common organism (12 episodes), adenovirus (2), cytomegalovirus (1) and bacteria (3) were also identified. The frequency of HC in transplants complicated by acute GVHD grade II-IV was 40% (p = 0.016), in children who had received prior CY was 43% (p < 0.001) and in mismatched transplants was 32% (p = 0.06). Four children who developed GVHD had exacerbations of symptoms associated with the use of high-dose steroid therapy. Our results suggest that most cases of delayed onset HC are temporally associated with an infective organism, predominantly papovavirus, and identify GVHD and prior CY as risk factors. Increased symptomatology was associated with acute GVHD and its treatment and this may be explained by the added immune suppression, resulting in greater viral reactivation and further mucosal damage.

Captopril-induced pemphigus vegetans with Charcot-Leyden crystals

A 78-year-old woman developed intertriginous vegetating plaques, mouth ulcers, and a cerebriform tongue after 11 months of captopril therapy. Findings of clinical, histologic, and immunofluorescence testing were consistent with a diagnosis of pemphigus vegetans. In addition, Charcot-Leyden crystals were observed within some of the intraepidermal, eosinophilic abscess cavities, which were bordered by granular cells undergoing keratinization. The skin lesions cleared rapidly after discontinuation of captopril. To the best of our knowledge, this report describes the first case of pemphigus vegetans induced by captopril.

Evaluation of a commercial enzyme immunoassay kit for the detection of Clostridium difficile toxin A

A new enzyme immunoassay (EIA) kit developed for the rapid detection of Clostridium difficile toxin A in faecal specimens, Premier (Meridian Diagnostics), was evaluated using 101 faecal specimens. Sixty-nine specimens were positive for Clostridium difficile by isolation of the organism and by cytotoxicity in tissue culture. The EIA for toxin A was positive in 49 of these 69 cases. No specimen that was negative for cytotoxicity was positive by EIA. Eight of the 32 specimens negative by both EIA and cytotoxicity assay yielded Clostridium difficile by culture. In five of these cases the cytotoxigenic status of the isolate was determined, and four were positive. There was no direct relationship between cytotoxin titre and EIA reading.