The occlusal status of disabled children

The occlusal status of children in 6 schools for the handicapped was determined using the Occlusal Index (O.I.) of Summers (1966). Two dentists examined 381 children who had not previously received orthodontic treatment. An additional questionnaire investigating treatment interests and habits was also completed for each child. The study showed that 74,5 per cent required treatment, 10,5 per cent had good occlusions and 15 per cent had slight malocclusions where treatment was not considered essential. The mean O.I. was 7,92 +/- 4,33. Schools with mainly cerebral and mentally disabled children had a slightly higher O.I. but the difference in values was not statistically significant. The analysis also showed that 40,6 per cent of children were interested in receiving orthodontic treatment, but only 0,5 per cent were planning to seek it. There is a need for orthodontic treatment amongst disabled children and this should be taken into account in future oral health care planning.     

Bilingual memory representation: A further test of dual coding theory.

Compared incidental recall for words coded as synonyms, translations, and copies in 28 Spanish-English, early and late onset bilingual undergraduates. 24 English-monolingual undergraduates recalled in draw, synonym, and copy conditions. Words in the synonym condition were recalled more than copied words by both groups of Ss, and bilingual Ss recalled imaged and translated words more often than synonyms. No differences were found between early and late onset bilinguals across words. It is argued that a dual coding view offers an explanation for these findings. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gulliver's further travels: the necessity and difficulty of a hierarchical theory of selection

For principled and substantially philosophical reasons, based largely on his reform of natural history by inverting the Paleyan notion of overarching and purposeful beneficence in the construction of organisms, Darwin built his theory of selection at the single causal level of individual bodies engaged in unconscious (and metaphorical) struggle for their own reproductive success. But the central logic of the theory allows selection to work effectively on entities at several levels of a genealogical hierarchy, provided that they embody a set of requisite features for defining evolutionary individuality. Genes, cell lineages, demes, species, and clades-as well as Darwin's favoured organisms-embody these requisite features in enough cases to form important levels of selection in the history of life. R. A. Fisher explicitly recognized the unassailable logic of species selection, but denied that thsi real process could be important in evolution because, compared with the production of new organisms within a species, the origin of new species is so rare, and the number of species within most clades so low. I review this and other classical arguments against higher-level selection, and conclude (in the first part of this paper) that they are invalid in practice for interdemic selection, and false in principle for species selection. Punctuated equilibrium defines the individuality of species and refutes Fisher's classical argument based on cycle time. In the second part of the paper, I argue that we have failed to appreciate the range and power of selection at levels above and below the organismic because we falsely extrapolate the defining properties of organisms to these other levels (which are characterized by quite different distinctive features), and then regard the other levels as impotent because their effective individuals differ so much from organisms. We would better appreciate the power and generality of hierarchical models of selection if we grasped two key principles: first, that levels can interact in all modes (positively, negatively, and orthogonally), and not only in the negative style (with a higher level suppressing an opposing force of selection from the lower level) that, for heuristic and operational reasons, has received almost exclusive attention in the existing literature; and second, that each hierarchical level differs from all others in substantial and interesting ways, both in the style and frequency of patterns in change and causal modes.     

The effect of occlusal reduction on pain after endodontic instrumentation

Since 1987, about 60 cases of porphyria cutanea tarda (PCT) associated with human immunodeficiency virus (HIV) have been reported. The respective roles of HIV and toxic hepatic factor in PCT remain unclear. We report 10 new cases and analyse the following toxic hepatic factors: hepatitis C and B, alcoholism, drugs. The route of HIV transmission to these 10 men were: IV drugs abuse (3), homo/bisexuality (4), heterosexuality (1), and unknown (2). When PCT was diagnosed, their average age was 38 years (29-54) and the HIV-infection had been established for 4.8 years (0.33-9). Seven men had HIV-related symptoms and a CD4+ lymphocyte count below 200/mm3. Cutaneous signs and urinary porphyrin count were characteristic. Alcohol abuse was present in 8/10 patients. AST, ALT and/or gamma GT were high in 9/10 patients; 5/10 patients had HCV antibodies (4 were HCV-PCR positive). HBs antigenemia was negative among the 5/8 patients with HBV antibodies; 10/10 patients took prescribed hepatotoxic drugs. Our series confirms the presence of toxic hepatic factors in PCT of HIV-positive patients. Hepatitis C, alcoholism and hepatotoxic drug consumption seem to be triggers for the appearance of PCT in HIV-positive patients.     

The axillo-axillary bypass graft: further experience

The recent utilization of the axillo-axillary bypass graft for revascularization of proximal subclavian or innominate artery occlusions has proved to be a successful operation, technically simple with a low operative morbidity. We have reviewed the reported experience to date and have added our experience of nine additional cases. The procedure has produced excellent results in all patients, with no evidence of postoperative "steal" from the donor limb. Preoperative hemodynamic defects were corrected. Our experience has led us to the conclusion that this simpler and safer extrathoracic approach should be considered as the procedure of choice when arterial lesions allow for its selection and use.     

The disaggregation theory of signal transduction revisited: further evidence that G proteins are multimeric and disaggregate to monomers when activated

We have compared the sedimentation rates on sucrose gradients of the heterotrimeric GTP-binding regulatory (G) proteins Gs, G(o), Gi, and Gq extracted from rat brain synaptoneurosomes with Lubrol and digitonin. The individual alpha and beta subunits were monitored with specific antisera. In all cases, both subunits cosedimented, indicating that the subunits are likely complexed as heterotrimers. When extracted with Lubrol all of the G proteins sedimented with rates of about 4.5 S (consistent with heterotrimers) whereas digitonin extracted 60% of the G proteins with peaks at 11 S; 40% pelleted as larger structures. Digitonin-extracted Gi was cross-linked by p-phenylenedimaleimide, yielding structures too large to enter polyacrylamide gels. No cross-linking of Lubrol-extracted Gi occurred. Treatment of the membranes with guanosine 5'-[gamma-thio]triphosphate and Mg2+ yielded digitonin-extracted structures with peak sedimentation values of 8.5 S--i.e., comparable to that of purified G(o) in digitonin and considerably larger than the Lubrol-extracted 2S structures representing the separated alpha and beta gamma subunits formed by the actions of guanosine 5'-[gamma-thio]triphosphate. It is concluded that the multimeric structures of G proteins in brain membranes are at least partially preserved in digitonin and that activation of these structures in membranes yields monomers of G proteins rather than the disaggregated products (alpha and beta gamma complexes) observed in Lubrol. It is proposed that hormones and GTP affect the dynamic interplay between multimeric G proteins and receptors in a fashion analogous to the actions of ATP on the dynamic interactions between myosin and actin filaments. Signal transduction is mediated by activated monomers released from the multimers during the activation process.     

Digital assessment of occlusal wear patterns on occlusal stabilization splints: a pilot study

The purpose of this study was to evaluate the compressive capabilities of the Herbert scaphoid screw system. A transverse osteotomy was performed at the waist of eight scaphoids removing a 3 mm wafer of bone. A custom-designed load washer was inserted within this defect to measure intrascaphoid compression during Huene guide application, during screw insertion, after screw insertion and after guide release. The intrascaphoid compression was noted to peak during screw insertion; however it dramatically decreased without any clinical subjective evidence of decreased insertional torque by the surgeon. The average final compression as a percentage of maximal compression was 38 (SD 26) %.     

Facially generated occlusal vertical dimension

Facial height has a profound effect on attractiveness. Occlusal vertical dimension (OVD) determines facial proportion at maximum intercuspation and influences facial dimension at rest. Deficient facial height visibly compromises optimal facial beauty. This article explores the dependent relationships between the OVD and facial esthetics, and discusses the role of facial analysis in determining an optimal OVD.     

The so-called congenital trigger digit: further experience

The authors reviewed 53 patients with 70 congenital trigger digits. Three of these were seen at an early age. Most "congenital" trigger digits present later than the neonatal period. A clear difference exists between trigger thumbs and trigger fingers. In our series, thumbs were more frequently affected, 30% were bilateral and none resolved spontaneously. The long fingers were less frequently affected, and two of them (28%) recovered without operation. All other children had an operative release of the A1 pulley of the flexor tendon sheath, with excellent results.     

Guiding occlusal development with functional appliances

Functional appliances have been used in orthodontics since their introduction by Pierre Robin almost one hundred years ago, however, our understanding of how they bring about orthodontic correction is still limited. This article is a brief overview of their history, mode of action, advantages and disadvantages, and includes the results of a study of attempts to control and minimise their side-effects using a recent development in functional appliances: the 'Teuscher Appliance'. This appliance combines a high-pull headgear with the activator, and is designed to reduce the often reported side-effects of functional appliances. The skeletal and dentoalveolar effects of treatment with the Teuscher Appliance on 40 consecutively-treated patients are reported and illustrated with four individual case reports. The results showed that the skeletal effect on the maxilla was a retardation of the normal forward and downward growth in 80 per cent of the cases, and that mandibular growth in 70 per cent of cases was forward. In patients whose mandibular growth was primarily in a vertical direction, such growth could be ascribed mainly to posterior rotation of the maxilla and/or the fact that the acrylic covering the lower posterior teeth to correct a deep bite was removed, promoting the eruption of these teeth and increasing the anterior vertical development. The dentoalveolar changes were characterised by retroclination of the maxillary incisors in 90 per cent of the patients, and were due to insufficient torque control by the built-in torque springs, which need further development. The mandibular incisors were well controlled by capping. The statistical analysis showed an inverse correlation between the initial incisor inclination and the change during treatment. This suggests that proclination of the lower incisors, as previously reported, is not a contra-indication to functional appliance treatment, provided the appliance is correctly designed. Overall, this study showed considerable individual response to treatment, and that the occlusal correction occurred through a combination of skeletal and dentoalveolar changes.     

Guiding occlusal development with functional appliances

In 24 patients with bacterial pneumonia, reliability of the samples routinely taken for etiologic diagnosis (sputum, throat swab, bronchial brushing, bronchoalveolar lavage fluid--BALF, blood, pleural fluid) was determined. Organisms detected in blood, pleural fluid, transbronchial biopsy (TBB) or percutaneous transthoracic needle aspiration biopsy (PTNAB) samples were considered as truly causative, whereas those isolated in at least two various samples from a single patient were considered as presumably causative. Most sensitive diagnostic samples were BALF, TBB and PTNAB (100% each). However, the specificity of BALF was very low (17%). Bronchial aspirate was highly sensitive (95%) but not specific (14%). Bronchial brushing was sensitive (86%) but its specificity low (14%). Sputum was hardly sensitive (40%) and had no specificity. Throat swab had virtually no diagnostic value because of its low sensitivity (10.5%) and specificity (50%).