A method to evaluate and compare two different intraoral radiographs of the same patient

Objective of this study was to determine the accuracy of the method of the clinical intraoral densitometry, to compare differences in the calculation with or without subtraction of the background adjacent soft-tissues from the stepwedge (SW) and to verify which regression model best fitted the experimental data in order to express the measured values in equivalents of SW thickness. Two intraoral radiographs, one after another, were made for each of 6 patients. A copper SW (6 steps, thickness 0.05-0.3 mm) was attached to each radiograph, trying to avoid the superimposition of the bony structures. Films were processed and digitized. Grey levels were measured on each step of the SW, on the background of the SW and on the same 3 randomly chosen regions of interest (ROIs) on each digitized image. The measurement with and without the subtraction of optical densities of the background around the SW from the optical densities of the SW was performed. For the calculation of the SW thickness equivalents, the regression analysis was performed by using different regression models. The best fitting regression model was the 3rd degree polynomial. The results were more precise when using the subtraction of the background overlapping the SW.     

Comparison of five detection methods for Helicobacter pylori

OBJECTIVE: To evaluate which diagnostic test is preferable for the diagnosis of Helicobacter pylori in patients with gastroduodenal disease. STUDY DESIGN: H pylori infection was diagnosed prospectively in 101 patients. Diagnosis of H pylori was made by tests based on five different principles: (1) culture, (2) direct histologic demonstration, (3) imprint cytology, (4) brushing cytology, and (5) gram staining of H pylori. Efficacy of each test was compared. RESULTS: All the tests were reliable for diagnosing H pylori infection; 73.3% of patients showed concordance in at least two tests. All the tests were positive in > 50% of patients. Significant concordance between brushing and imprint cytology was also determined. These two tests have almost similar specificity when compared to other tests. CONCLUSION: When patients undergo upper endoscopy, we recommend taking biopsy specimens for culture and histology. H pylori can be assessed equally well with all the tests, but imprint and brushing cytology have the advantage of rapid response, specificity, much lower cost and reproducibility.     

Increasement of Heterologous Expression of Recombinant Vit v 1 in Pichia pastoris KM71 by Nonionic Detergents as a Cost-effective Approach

Applied Biochemistry and Microbiology - Vit v 1 as a lipid-transfer protein is a major allergen of grapes (Vitis vinifera) that elicits food allergy in many patients in Iran. Todays, recombinant...     

Decreasing of residual alveolar ridge height in complete denture wearers. A five year follow up study

The resorption of the residual alveolar ridges is a chronic and continuous process of bone remodeling. The aim of this study was to analyse the rate of residual ridge resorption at different sites in the both jaws in complete denture wearers, through a five-year period of denture wearing. Residual ridge changes were measured on successive lateral cephalograms at 5 measurement points of the maxilla and the mandible. The first lateral radiograph was obtained at the delivery of complete dentures. The second lateral cephalogram was obtained after five years of denture wearing. Measurements were performed using a calibrated grid. The results of this study showed the existence of a significant alveolar ridge resorption at all five measurement points of the maxilla and the mandible. The observed variables, such as body mass index and the night time denture wearing had no significant influence on the rate of residual alveolar ridge resorption (p > 0.05). The duration of edentulousness had a significant influence on the rate of residual ridge resorption with significantly higher amounts of alveolar bone height decrease in those patients who had lost the last remaining teeth more recently.     

Depression, somatization and anxiety in female patients with temporomandibular disorders (TMD)

The aim of this research was to determine the possible differences in degrees of depression, somatization and anxiety between the acute and chronic female patients with temporomandibular disorders (TMD), and whether these differences exist in healthy female patients. Ninety female patients were involved in this research; 60 of them were TMD patients of the Dental Polyclinic, while other 30 females came for a routine recall visit and had no problem related to TMD. Patients were aged 22 to 67 years, the average age being 38.5 +/- 12 years. All patients were asked to fill in the RDC/TMD protocol and three psychological tests (Emotions Profile Index, Somatization Scale and life Events Scale). Following the analysis of the RDC/TMD protocol and psychological tests, it was determined that the chronic female patients had higher depression and somatization scores in comparison with the acute patients (p < 0.01); the acute patients self-perceive higher levels of anxiety in relation to the control group; furthermore, the patients reporting higher levels of depression were more inclined to somatization and had experienced a greater number of stress events in the past six months. It is beyond doubt that patients suffering from the TMD's exhibit higher levels of depression, somatization and anxiety compared to the healthy ones, which proves that physiological factors may play a predisposing role in combination with reduced level of body tolerance to pain, and a decreased tolerance to stress.     

Mechanism and hydrophobic forces driving membrane protein insertion of subunit II of cytochrome bo 3 oxidase

Subunit II (CyoA) of cytochrome bo₃ oxidase, which spans the inner membrane twice in bacteria, has several unusual features in membrane biogenesis. It is synthesized with an amino-terminal cleavable signal peptide. In addition, distinct pathways are used to insert the two ends of the protein. The amino-terminal domain is inserted by the YidC pathway whereas the large carboxyl-terminal domain is translocated by the SecYEG pathway. Insertion of the protein is also proton motive force (pmf)-independent. Here we examined the topogenic sequence requirements and mechanism of insertion of CyoA in bacteria. We find that both the signal peptide and the first membrane-spanning region are required for insertion of the amino-terminal periplasmic loop. The pmf-independence of insertion of the first periplasmic loop is due to the loop's neutral net charge. We observe also that the introduction of negatively charged residues into the periplasmic loop makes insertion pmf dependent, whereas the addition of positively charged residues prevents insertion unless the pmf is abolished. Insertion of the carboxyl-terminal domain in the full-length CyoA occurs by a sequential mechanism even when the CyoA amino and carboxyl-terminal domains are swapped with other domains. However, when a long spacer peptide is added to increase the distance between the amino-terminal and carboxyl-terminal domains, insertion no longer occurs by a sequential mechanism.     

Linear vertical jaw resorption potential in elderly complete denture wearers: a five-year follow-up study

Human bones decrease in quality and increase in porosity beginning at about the third decade of life. The aim of this study was to establish an equation to predict the maxillary and mandibular linear vertical resorption potential for elderly edentulous patients on the basis of the analysis of the cervical vertebrae in a single cephalometric radiograph. The morphology of the bodies of the third and fourth cervical vertebrae and measurements of linear vertical resorption in the frontal region of the jaws were analyzed in two consecutive cephalometric observations of 26 elderly edentulous patients over the five-year period of wearing complete dentures. An equation was determined to obtain maxillary and mandibular linear vertical resorption on the basis of measurements in the third and fourth cervical vertebral bodies and the average errors between the predicted and the actual values were 0.14 mm. The cervical vertebrae exhibited significant decrease in the height and width, and residual alveolar ridges exhibited significant decrease in the height over the 5-year period of wearing dentures (p < 0.01). These results suggest that using cervical vertebral measurements might allow predicting the maxillary and mandibular resorption for edentulous elderly patients wearing complete dentures.     

The patient's and the therapist's evaluation of complete denture therapy

A total of 222 patients were studied. In a questionnaire patients graded their complete dentures of different age and quality, depending on the level of satisfaction, using the modified analogue-visual scale from 1 to 5. The dentist assessed the same dentures, as well as the denture bearing area. The patients' assessments were surprisingly high, the grades were bigger than the therapist's (p < 0.05), but in disappointed patients the grades were smaller than the therapist's (p < 0.05). It seems that the dentist is more critical in assessments than the patient. No significant difference existed between chewing and denture stability and between stability and the comfort of wearing lower full denture (p > 0.05). Unstable denture aggravates chewing and causes pain and discomfort on the bearing area. It seems that subjective factors in patients, expectations of the denture or the number of previous dentures play a role in satisfaction, not only the quality of denture bearing area and the quality of a denture.     

Management of frontal sinus fractures

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the radiographic and clinical diagnosis of frontal sinus fractures. 2. Identify various management approaches to the frontal sinus fracture and the indications for each. 3. Understand the rationale behind the decision of sinus obliteration when needed. 4. Recognize the most common complications arising from frontal sinus fracture treatment and the methods of avoiding or managing these complications. SUMMARY: Frontal sinus fracture management is still controversial and involves preserving function when feasible or obliterating the sinus and duct, depending on the fracture pattern. There is no single algorithm for the choice of management, but appropriate treatment depends on an accurate diagnosis using physical examination, computed tomography data, and the findings of intraoperative exploration. The amount and location of fixation and the need for frontonasal duct and sinus obliteration or elimination of the entire sinus depend on the anatomy of the fracture in general and the extent of involvement of the anterior wall of the sinus, the frontonasal duct, and the posterior wall in particular. This article discusses an algorithm for frontal sinus fractures that was obtained from the literature and modified according to the authors' experience. The decision-making process presented by the authors has withstood the test of time over a period of more than 20 years in their practice and has been proven to be safe and efficacious in treating frontal sinus fractures of all types.