Dental color assessment through TTB exercises.

Aim.To verify the impact of taking the Toothguide Training Box (TTB) exercise in improving the individual ability to correctly determine dental color. Material and method.A prospective study was conducted on the 5th year dental students. The participants were required to carry out 3 distinct steps: visual color determination for sample tabs out of the 3DMaster shade guide, the TTB exercise and another color determination after training completion. Results.The sample included 60 students (19M/ 41F) with a mean age of 24, which made 360 color determinations of 6 shade tabs before and after TTB exercise. 32,5% (n=117) of the color determinations were incorrect in both moments, and the value was incorrectly determined just in 11% of them. Students found 3L1.5 and 3M2 colors as the hardest to determine. The results suggested that a single TTB training exercise did not have a high positive influence on the individual capacity to correctly determine the color for tabs out of the shade guide. Conclusions.While there is no evidence of an immediate positive impact of the TTB exercise in evaluating and determining different color variations for sample key elements, through repeat exercises, the individual perception can be improved and thus the correct determination of dental color and its correct codification can be increased. ABBREVIATIONS: TTB = Tooth Training Box, CIE = Commission internationale de l'éclairage, L = lightness, C = chroma, H = hue.

Therapeutical attitudes in tooth supported overdentures with ball attachements. Case report.

Tooth supported overdenture with ball attachments has a number of advantages in prosthetics, but presents some difficulties as well, which sometimes make impossible the use of these anchoring systems; these difficulties should be well known. In this regard we present a suggestive case. It is the case of a patient, aged 57, who came for treatment, suffering from subtotal maxillary and mandibular edentulism (present 11 and 21, respectively 33 and 43), previously having an overdenture prosthesis on natural teeth, with special systems - ball attachment type, dissatisfied with the treatment (due to repeated fractures and functional intolerance to dentures). Clinical examination revealed an increase of the vertical dimension of occlusion and reduced prosthetic space at a correct, functional DVO value, aspects that were explaining the patient's reported complaints. As a therapeutic approach, having into consideration the balance conditions that were favorable for complete dentures and the large ball attachments volume, which did not allow keeping them at a functional DVO at any of the jaws, and the relatively young age of the patient, it was decided to remove the ball attachments and to keep the teeth for a simple overdenture, both to the maxillar and the mandible, over coronary reduced teeth, enough to allow the denture thickness at a functional DVO. Good end result of prosthetics, with stable, functional dentures, which were well tolerated and offered satisfaction to the patient, have led to an increased quality of life.

Salivary changes related to systemic diseases in the edentulous patients.

INTRODUCTION: The relatively frequent systemic comorbidities of geriatric patients can be linked to salivary changes, which may induce oral alteration and discomfort with the removable prosthesis. The aim of the study was to evaluate the salivary parameters in completely edentulous patients treated by removable prosthesis, in relation to their general health status. MATERIAL AND METHOD: A cross-sectional study was performed on 30 completely edentulous patients, 53% male and 47% female, aged between 53 and 84. The evaluation of the salivary parameters (oral hydration index, pH and salivary flow, viscosity and saliva buffer capacity) was performed with the Saliva Check Buffer kit (GC Corporation). RESULTS: The salivary changes encountered were the following: low hydration level (63%), high saliva viscosity (57%), below-average pH (27%), reduced salivary flow (77%) and low saliva buffer capacity (80%). A reduced salivary flow and saliva buffer capacity was found in women. A lower buffer capacity of the saliva was found in patients with respiratory and gastro-intestinal disease. CONCLUSIONS: The alterations of the salivary flow are relatively frequent in geriatric patients, removable denture wearers, with compromised systemic status. These changes may be a risk factor for denture stomatitis and oral candidiasis, with a negative effect on the patient's comfort and quality of life.

Imaging technique for the complete edentulous patient treated conventionally or with mini implant overdenture.

RATIONALE: The imaging methods are more and more used in the clinical process of modern dentistry. Once the implant based treatment alternatives are nowadays seen as being the standard of care in edentulous patients, these techniques must be integrated in the complete denture treatment. AIM: The study presents some evaluation techniques for the edentulous patient treated by conventional dentures or mini dental implants (mini SKY Bredent) overdentures, using the profile teleradiography. These offer data useful for an optimal positioning of the artificial teeth and the mini dental implants, favoring to obtain an esthetic and functional treatment outcome. We proposed also a method to conceive a simple surgical guide that allows the prosthetically driven implants placement. MATERIAL AND METHOD: Clinical case reports were made, highlighting the importance of cephalometric evaluation on lateral teleradiographs in complete edentulous patients. A clinical case that gradually reports the surgical guide preparation (Bredent silicon radio opaque), in order to place the mini dental implants in the best prosthetic and anatomic conditions, was presented. CONCLUSIONS: The profile teleradiograph is a useful tool for the practitioner. It allows establishing the optimal site for implant placement, in a good relation with the overdenture. The conventional denture can be easily and relatively costless transformed in a surgical guide used during implant placement.

Two implant overdenture--the first alternative treatment for patients with complete edentulous mandible.

Given the increasing life expectancy in the coming years, dental practitioners, as other specialists from different medical fields, will encounter an increasing number of complete edentulous patients. These patients, with a longer active life and higher standards of life quality, will have different expectations for their complete dentures, higher than the standard treatment that uses conventional complete dentures. Two-implant overdenture is considered the first alternative treatment in complete edentulous mandible, according to current medical standards established by a team of specialists in prosthodontics and implantology, and globally known as the McGill Consensus from McGill University, Montreal, Canada. The Consensus was established during a-day-and-a-half session of presentations done by experts who presented data, scientific information on the subject, and, not less significant, personal experiences of participants and patients. Overdenture on implants, as an alternative treatment for complete edentulous mandible, has multiple benefits in achieving better conditions of prosthesis: balance and effectiveness, with positive effects on oral structures, aesthetics, and quality of life. Mandibular two-implant overdenture, established as a standard treatment by the highest international forum, should gradually become the first choice of treatment in complete edentulous mandible.

Standardless PIXE analysis of thick biomineral structures.

The particle-induced X-ray emission (PIXE) of thick biomineral targets provides pertinent surface analysis, but if good reference materials are missing then complementary approaches are required to handle the matrix effects. This is illustrated by our results from qualitative and semiquantitative analysis of biomaterials and calcified tissues in which PIXE usually detected up to 20 elements with Z > 14 per sample, many at trace levels. Relative concentrations allow the classification of dental composites according to the mean Z and by multivariate statistics. In femur bones from streptozotocin-induced diabetic rats, trace element changes showed high individual variability but correlated to each other, and multivariate statistics improved discrimination of abnormal pathology. Changes on the in vitro demineralization of dental enamel suggested that a dissolution of Ca compounds in the outermost layer results in the uncovering of deeper layers containing higher trace element levels. Thus, in spite of significant limitations, standardless PIXE analysis of thick biomineral samples together with proper additional procedures can provide relevant information in biomedical research.

Fatty-acid peroxidation in relation to trace elements in serum of patients with homozygous sickle-cell anemia and beta-thalassemia: a gas-chromatographic study.

Due mainly to a deeply disturbed iron metabolism, intense production of oxygen-derived free radicals occurs in genetic hemoglobinopathies such as homozygous sickle-cell anemia and beta-thalassemia. Together with impairments in the natural factors involved in oxy-radical detoxication, this results in intense oxidative stress leading to lipid peroxidation in the blood components. In search of peroxidation effects, we undertook a gas chromatographic study of both the total and phospholipid-bound fatty acids in the serum from sickle-cell disease and beta-thalassemia patients. Specific alterations of pathologic origin have been evidenced in the profiles of total and phospholipidic fatty acids, as well as in the elongation-desaturation ratios of the total fatty acids. Results are consistent with lipid peroxidations and fatty-acid biosynthesis disturbances in both diseases, but more severe in thalassemia than in sickle-cell anemia. Increased serum selenium in the latter disease might exert a protective action against lipid peroxidation.

Electron spin resonance study of the erythrocyte membrane fluidity changes in diabetes.

The membrane fluidity of intact erythrocytes from diabetic patients and sex-matched controls has been examined between 20 and 40 degrees C by electron spin resonance spectroscopy using the 5-doxyl palmitic acid spin label. In contrast to the normal erythrocytes, in both types of diabetes a significant non-linearity was found around 30 degrees C in the fluidity-temperature plots of the lipid bilayer. This was assigned to a phase transition normally absent in the 20-40 degrees C range. The magnitude of the bilayer fluidity showed a little decrease in insulin-dependent diabetes and an increasing trend vanishing around 37 degrees C in non-insulin-dependent diabetes. In addition, we observed two protein-immobilized lipid subpopulations, showing slightly higher apparent concentrations and modified fluidity in diabetes. Membrane composition alterations, mainly in the fatty acid concentrations, may explain the fluidity changes. Our results, although preliminary in a clinical sense because the number of investigated patients was too small, evidenced specific and complex changes of the erythrocyte membrane fluidity in diabetes and demonstrated the high potential of the spin label approach for the diabetic medicine.