Could medications and biologic factors affect post-orthodontic tooth movement changes? A systematic review of animal studies

Immediately after the removal of orthodontic appliances, the teeth might start to drift away from their corrected position in an attempt to reach a new equilibrium. Medications and biologic factors could potentially modulate these processes. The objective of the present systematic review is to systematically investigate and appraise the quality of the evidence regarding the effect of various medications and biologic factors on the rate of relapse following active tooth movement. Search without restrictions in eight databases and hand searching until April 2020 were conducted. Studies performed on animal models investigating the effects of medication and biologic factors on the rate of relapse following orthodontic tooth movement were considered. Following study retrieval and selection, relevant data were extracted and the risk of bias was assessed. Seventeen studies were finally identified, mostly at either high or unclear risk of bias. Ketorolac did not show any significant effects on relapse, while the administration of tetracycline, atorvastatin, psoralen and raloxifene decreased it. Overall, the same result was observed with bisphosphonates with the exception of low dosage of risedronate, which did not have an effect. Osteoprotegerin and strontium resulted in reduced relapse, but not in the immediate post-administration period. Inconsistent or conflicting effects were noted after the use of simvastatin and relaxin. The quality of the available evidence was considered at best as low. It can be concluded that specific medications and biologic factors may have an effect on the rate of relapse following tooth movement. The orthodontist should be knowledgeable about the substances potentially affecting retention.     

Nanomagnetic Modulation of Tumor Redox State

Modulation of reactive oxygen and nitrogen species in a tumor could be exploited for nanotherapeutic benefits. We investigate the antitumor effect in Walker-256 carcinosarcoma of magnetic nanodots composed of doxorubicin-loaded Fe₃O₄ nanoparticles combined with electromagnetic fields. Treatment using the magnetic nanodot with the largest hysteresis loop area (3402 erg/g) had the greatest antitumor effect with the minimum growth factor 0.49 ± 0.02 day^–1 (compared to 0.58 ± 0.02 day^–1 for conventional doxorubicin). Electron spin resonance spectra of Walker-256 carcinosarcoma treated with the nanodots, indicate an increase of 2.7 times of free iron (that promotes the formation of highly reactive oxygen species), using the nanodot with the largest hysteresis loop area, compared to conventional doxorubicin treatment as well as increases in ubisemiquinone, lactoferrin, NO-FeS-proteins. Hence, we provide evidence that the designed magnetic nanodots can modulate the tumor redox state. We discuss the implications of these results for cancer nanotherapy.     

Ethics and fraud in science: a review of scientific misconduct and applications to craniofacial research

The purpose of this article is to review and discuss the occurrence of fraud in biomedical research and analyze the definition, origin, and various forms of scientific misconduct. Fraud in research most often involves reporting data for which no records of experiment or population are present; manipulating research materials, equipment, or procedures to arrive at the desirable result; adding, changing, or omitting results, which positively or negatively relate to the hypothesis that the research intends to test; and incorporating ideas, statements, procedures of others' work without permission and appropriate credit to the source. The etiologic factors contributing to this deviant behavior, and measures taken by relevant bodies to eliminate this phenomenon are discussed. Ethical and integrity aspects of craniofacial research are explored and a set of criteria to facilitate rigorous assessment of the integrity of clinical and basic research protocols is proposed. These include (1) an integrity-focused training of researchers to adhere to specific laboratory procedure and tactics which discourage fraud; (2) appointment of external reviewers to detect unusual and suspicious experimental process or data patterns; and (3) encouragement of multicenter trials. Although it is widely recognized that the sole determinant of scientific misconduct is the individual investigator's integrity, a number of precautions may effectively reduce the prevalence of this event, which may affect the status and trends of biomedical research in general.     

Frontal cephalometric study of dentofacial morphology in children with bilateral clefts of lip, alveolus and palate

The transverse dentofacial morphology of 36 children with bilateral cleft lip, alveolus and palate was studied by means of a frontal proportional cephalometric analysis at the ages of three, eight and twelve years. Comparison of the variables of the cleft group was made with the normal dimensions as obtained from the Bolton cephalometric templates. The results indicated that the BCLP group presented characteristics and significant differences from the normal in the dimensions of the nasal septum width and the mandibular intergonial width as they are both related to the interorbital width, the maxillary intermolar width as it is related to the mandibular intermolar width and the maxillary width as it is related to the mandibular intergonial width at all three ages. The maxillary base and intermolar widths, although significantly different at the ages of three and eight years, showed no significant deviation from normality at the age of twelve years. Following orthodontic treatment between the ages of seven to twelve years, the maxillary intermolar width of the treated subgroup was significantly larger than in the untreated subjects.     

Concerns, motivation, and experience of orthognathic surgery patients: a retrospective study of 152 patients

Patient perceptions and motivations for undergoing orthognathic surgery were evaluated retrospectively by a 15-item self-administered questionnaire. Surgical risk was the major reservation concerning having an operation, and change in appearance and cost of treatment were of next greatest concern. Of the 152 patients, 78.3% would elect to have surgery again. Female patients desired improvement in appearance more than male patients.     

Surface characterization of retrieved NiTi orthodontic archwires

The structure and morphological condition of retrieved NiTi orthodontic archwires was evaluated and any possible alterations in the surface composition of the alloy following 1-6 months in vivo were characterized. NiTi wires (GAC, German Orthodontics, ORMCO) of various cross-sections were collected through a retrieval protocol and were subjected to multi-technique characterization. Optical microscopy revealed islands of amorphous precipitants and accumulated microcrystalline particles. Micro MIR-FTIR investigation of the retrieved samples demonstrated the presence of a proteinaceous biofilm, the organic constituents of which were mainly amide, alcohol, and carbonate. Scanning electron microscope and X-ray microanalysis showed that the elemental species precipitated on the material surface were Na, K, Cl, Ca, and P, forming NaCl, KCl, and Ca-P precipitates. Increased intra-oral exposure was consistently associated with the presence of a mature film, while evidence of alloy delamination, pitting, and crevice corrosion, as well as a notable reduction in the alloy grain size was observed. Intra-oral exposure of NiTi wires alters the topography and structure of the alloy surface through surface attack in the form of pitting or crevice corrosion or formation of integuments. Further in vivo research is required to resolve the implications of the described ageing pattern in the corrosion resistance of the alloy, the potential for nickel leaching, as well as bracket-archwire friction variants.     

Long-term assessment of psychologic outcomes of orthognathic surgery.

PURPOSE: This long-term study of post-orthognathic surgery patients aimed at assessing perceptions of problems with physical and psychologic functioning, self-concept, body image, and satisfaction with the surgical outcome based on subjective evaluations. In addition, the patient's perception of self-concept, body image, and function was compared with the perception of pretreatment patients and controls with no treatment need. Patients and Methods: One hundred seventeen patients who underwent orthognathic surgery 10 to 14 years earlier and participated in a psychologic study 10 years earlier received questionnaires that were composed of 4 instruments designed to assess these factors. A sample of 92 persons representing a population without treatment need and 39 patients requesting treatment for a malocclusion served as control groups. RESULTS: The findings of this study support the hypothesis that improvement in appearance brought about by orthognathic surgery is associated with improvement in psychosocial adjustment. Orthognathic surgery resulted in subjective estimation of function, appearance, health, and interpersonal relationships that was higher than that among pretreatment and no-treatment control groups. The level of body image and self-esteem approximated but did not reach that of a nonpatient population. CONCLUSIONS: In view of the current psychologic and social environment, patients should be offered the appropriate treatment to correct a disfigurement if it is subjectively perceived by them as a handicap, in part to improve the psychologic outcome.     

Treatment of poisoning induced cardiac impairment using cardiopulmonary bypass: a review

Severe poisoning can cause potentially fatal cardiac depression. Cardiopulmonary bypass (CPB) can support the depressed myocardium, but there are no clear indications or guidelines available on its use in severe poisoning. A review was conducted of relevant papers in the available literature (seven single case reports of both deliberate and accidental ingestion of cardiotoxic drugs and two animal studies). Although CPB is rarely used in the management of poisoning, it may have potential benefits for haemodynamic instability not responding to conventional measures. At present there is insufficient evidence concerning the use of CPB as a treatment for severe cardiac impairment due to poisoning (grade C). This review suggests that in patients with severe and potentially prolonged reversible cardiotoxicity there is potential for full survival with CPB, provided that the patient has not already sustained hypoxic cerebral damage due to resistant hypotension prior to its use.     

The Emerging Role of Neutrophil to Lymphocyte Ratio in Determining Colorectal Cancer Treatment Outcomes: A Systematic Review and Meta-Analysis

Background

There is growing evidence suggesting that the neutrophil to lymphocyte ratio (NLR) can act as an independent predictor of long-term outcomes in patients undergoing treatment for colorectal cancer (CRC). This study aims to systematically review the role of NLR in predicting survival for patients with CRC undergoing treatments, and to evaluate its utility within a CRC surveillance program.

Methods

This meta-analysis was performed according to PRISMA guidelines. Outcomes of interest included disease-free survival (DFS) for patients undergoing treatment with curative intent and progression-free survival (PFS) in patients undergoing treatments with palliative intent.

Results

Thirteen observational cohort studies published from 2007 to 2013 evaluated the role of NLR as a predictor of outcome following treatment for CRC. These included (i) patients undergoing surgery to resect the primary cancer (seven studies); (ii) those undergoing palliative chemotherapy (three studies); and (iii) patients undergoing potentially curative treatments for CRC liver metastases (three studies). When all studies were considered, a high pretreatment NLR independently predicted survival (HR 2.08; 95 % CI 1.64–2.64). A high NLR also predicted significantly poorer survival in each of the three groups. Finally, over a 3-year follow-up period, high NLR became a significant predictor of poor outcome at year 2 (HR 2.76; 95 % CI 2.06–3.69; p < 0.00001) and 3 (HR 2.03; 95 % CI 1.48–2.78; p < 0.0001), but not in the first year of follow-up (HR 1.47; 95 % CI 0.89–2.41; p = 0.13).

Conclusions

Elevated preoperative NLR is associated with poorer survival in CRC patients undergoing treatment and may have a role in CRC surveillance programs as a means of delivering more personalized cancer care.