New and Recovered Temporary Anchorage Devices,In Vitro Assessment of Structural and Surface Properties

The orthodontic miniscrew (TADs) is a device that is fixed into bone in the short term for the purpose of enhancing orthodontic anchorage. The aim of our study was to investigate the structural and surface properties of recovered TADs after orthodontic treatment, and compare them to new TADs. TADs (n = 15) from the same manufacturer (Absoanchor; Dentos, Daegu, Korea) were assessed; n = 10 were recovered from patients after orthodontic treatment and n = 5 were new. We performed electrochemical investigations, scanning electron microscopy (SEM) and microbiological analysis. Qualitative analysis on general electrochemical polarization revealed that the TADs retrieved from the patients provided much lower current densities in the passivity zone, and the oxidative processes taking place on their surface were of lower intensity. The surface morphologies of the tips of the retrieved mini-implants showed less sharp tips and smooth surfaces. Defects in the form of pores or cracks could be identified in both evaluated TAD groups. All retrieved TADs showed signs of biological materials (SEM analysis) and contamination on their surfaces. In conclusion, these results can assist orthodontists in comprehending the complexities of TAD behavior with respect to their design and structure.     

The relation between outcome expectation,therapeutic alliance,and outcome among depressed patients in group cognitive-behavioral therapy

Objective: Although patients’ expectation for improvement correlates with their treatment outcome, there remains limited information regarding the mechanisms through which outcome expectation influences outcome. Although several studies have revealed alliance as a mediator of the expectancy-outcome relation, most have focused on individual psychotherapy only. More research is needed examining mediators, including alliance quality, of the outcome expectation-outcome relation in group therapy. Method: This study focused on such associative chains among 91 depressed outpatients who completed 10 weeks of group cognitive-behavioral therapy. We conducted simple and multiple mediation analyses, accounting for the nested data structure. Results: As predicted, we found: (i) The relations between baseline outcome expectation and both posttreatment anxiety and depression were mediated by alliance quality; (ii) the early therapy outcome expectation-posttreatment anxiety relation was mediated by mid-treatment alliance; (iii) the relation between early alliance and posttreatment interpersonal problems was mediated by during-therapy outcome expectation; and (iv) the relation between baseline outcome expectation and posttreatment interpersonal problems was mediated by two variables acting in turn, early alliance and during-therapy outcome expectation. All other tested models were not significant. Conclusions: Results suggest that bidirectional relations between outcome expectation and alliance, with both directions influencing outcome. Clinical and empirical implications are discussed.     

Expression of EGFR in Paired New and Recurrent Glioblastomas

Background: The aim of this study was to analyse the expression of EGFR in newly diagnosed and recurrent glioblastoma multiforme (GBM). Materials and Methods: Our study included a total of 48 paired samples collected from 24 patients diagnosed with GBM. The intensity of EGFR cytoplasmatic staining was scored on a scale of 1-3 (weak, intermediate or strong). Results: We found EGFR overexpression in 23 patients (96%) with newly diagnosed GBM, while all recurrent tumours overexpressed EGFR. Ten recurrent tumours (42%) had a lower expression than their new counterpart 13 tumours (54%) had a similar expression, and only one case (2%) had increased expression on recurrence. The expression of EGFR in newly diagnosed GBM was significantly correlated with EGFR expression in recurrent tumour (p 0.036). In addition, new GBMs with strong EGFR expression had a mean relapse-free interval of 11.5 months (p0.017). A benefit of combined therapy was observed in the radiotherapy-plus-chemotherapy group where the average time was 11 months (p0.011), as compared with surgery/radiotherapy alone (average time 6.8 months). Conclusions: The present data show that EGFR is overexpressed in paired GBMs. The discrepancies of EGFR expression between the primary tumour and the recurrence suggest heterogeneity of GBMs but also unity at relapse.     

Undesirable dental hard tissue effects hypothetically linked to orthodontics - a microscopic study

Like any other medical intervention, the orthodontic treatment may have, besides the positive effects, also unwanted secondary consequences. The aim of this study was to evaluate the changes present in dental hard tissue associated with orthodontic treatment. The stereo-microscopic ex vivo analysis was performed on two sets of maxillary first premolars undergoing orthodontic treatment for a long period of time (12 and 23 months); five teeth with other clinical situations were used as controls. By analyzing the teeth undergoing orthodontics, enamel color alterations were mainly found adjacent to the bracket, more pronounced in the gingival area, suggesting the need for a correct oral hygiene around it. Roughness was higher on the enamel surface corresponding to the bracket's base, aspect linked to the resign impregnation during bonding procedures. At the apical part, changes regarding contour, appearance and surface roughness were noticed. These modifications were suggestive for the presence of apical root resorption. The severity of root resorption was not correlated with the duration of treatment. In conclusion, through microscopic analysis changes that may be associated with orthodontic treatment have been observed in both crown and apical level.     

The lateral incisive canals of the adult hard palate - aberrant anatomy of a minor form of clefting?

Except the oral clefts and their associated dental development disturbances, no other discrete morphologies are reported in the literature as related to altered fusions of the fetal maxilla and premaxilla. We report here two cases related by the persistence in adult of an aberrant canal at the fusion site of the fetal premaxilla and maxilla. The first case presents an anastomosis of the superior anterior alveolar and greater palatine nerves, encountered during the dissection of a human adult male cadaver; that anastomosis, bilaterally present, projected on the aforementioned fusion site and traversed the hard palate to continue within the maxillary sinus wall. The second case evidenced on CT the unilateral presence of aberrant lateral incisive canals (LIC) at the level of the fetal premaxilla and maxilla fusion site; those canals, external (1.5 mm diameter) and internal (1.07 mm diameter), were corresponding as location to that one traversed by the aberrant anastomosis in the first case. Both LIC opened inferiorly but not superiorly, rather seeming to communicate with the bony canals within the nasal fossa floor at that level. We consider that such aberrant canals and nerves may represent very rare forms of clefting, previously undescribed; the possible anastomoses of the superior anterior alveolar and greater palatine nerves can be altered during a Le Fort I fracture and may be the morphology that can explain aberrant clinical nervous distributions at the level of the upper dentoalveolar arch and hard palate.     

Neurodegeneration: An early event of diabetic retinopathy

Diabetic retinopathy (DR) has been classically considered to be a microcirculatory disease of the retina caused by the deleterious metabolic effects of hyperglycemia per se and the metabolic pathways triggered by hyperglycemia. However, retinal neurodegeneration is already present before any microcirculatory abnormalities can be detected in ophthalmoscopic examination. In other words, retinal neurodegeneration is an early event in the pathogenesis of DR which predates and participates in the microcirculatory abnormalities that occur in DR. Therefore, the study of the mechanisms that lead to neurodegeneration will be essential to identify new therapeutic targets in the early stages of DR. Elevated levels of glutamate and the overexpression of the renin- angiotensin-system play an essential role in the neurodegenerative process that occurs in diabetic retina. Among neuroprotective factors, pigment epithelial derived factor, somatostatin and erythropoietin seem to be the most relevant and these will be considered in this review. Nevertheless, it should be noted that the balance between neurotoxic and neuroprotective factors rather than levels of neurotoxic factors alone will determine the presence or absence of retinal neurodegeneration in the diabetic eye. New strategies, based on either the delivery of neuroprotective agents or the blockade of neurotoxic factors, are currently being tested in experimental models and in clinical pilot studies. Whether these novel therapies will eventually supplement or prevent the need for laser photocoagulation or vitrectomy awaits the results of additional clinical research.