Laser assisted restorative mineralization of dental enamel

2021 ◽  
Author(s):  
Antonios D. Anastasiou ◽  
Emaan Alshubheb ◽  
Vasiliki C. Panagiotopoulou ◽  
Simon Strafford ◽  
Tom J. Edward ◽  
...  
Keyword(s):  
Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.


Author(s):  
M. John Hicks

Acid-etching of enamel surfaces has been performed routinely to bond adhesive resin materials to sound dental enamel as a caries-preventive measure. The effect of fluoride pretreatment on acid-etching of enamel has been reported to produce inconsistent and unsatisfactory etching patterns. The failure to obtain an adequate etch has been postulated to be due to fluoride precipitation products deposited on the enamel surface. The purpose of this study was to evaluate the effects of fluoride pretreatment on acid-etching of carieslike lesions of human dental enamel.Caries-like lesions of enamel were created in vitro on human molar and premolar teeth. The teeth were divided into two fluoride treatment groups. The specimens were exposed for 4 minutes to either a 2% Sodium Fluoride (NaF) solution or a 10% Stannous Fluoride (SnF2) solution. The specimens were then washed in deionized-distilled water. Each tooth was sectioned into four test regions. This was carried out to compare the effects of various time exposures (0 to 2 minutes) and differing concentrations (10 to 60% w/w) of phosphoric acid (H3PO4) on etching of caries-like lesions. Standard preparation techniques for SEM were performed on the specimens.


Author(s):  
T. L. Hayes

Biomedical applications of the scanning electron microscope (SEM) have increased in number quite rapidly over the last several years. Studies have been made of cells, whole mount tissue, sectioned tissue, particles, human chromosomes, microorganisms, dental enamel and skeletal material. Many of the advantages of using this instrument for such investigations come from its ability to produce images that are high in information content. Information about the chemical make-up of the specimen, its electrical properties and its three dimensional architecture all may be represented in such images. Since the biological system is distinctive in its chemistry and often spatially scaled to the resolving power of the SEM, these images are particularly useful in biomedical research.In any form of microscopy there are two parameters that together determine the usefulness of the image. One parameter is the size of the volume being studied or resolving power of the instrument and the other is the amount of information about this volume that is displayed in the image. Both parameters are important in describing the performance of a microscope. The light microscope image, for example, is rich in information content (chemical, spatial, living specimen, etc.) but is very limited in resolving power.


2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mashkoor Ahmad Lone ◽  
Dr. P. Ganesan

The practice of placing deprived children having least or no emotional and material resources, in orphanages has since long been prevailing in socio -economically poor Asian countries. A sample of 30 children residing in orphanage in district Anantnag in the age group of 13-18 years was selected for the present study. Most of the children were found socially and psychologically disturbed. As per Indian Academy Paediatrics (IAP) classification with respect to weight for age the condition was not bad that as approximately 67% percent of the children were found to be normal. In the same way height for age as per Waterloo’s classification shown that more than half of the children were normal. On clinical examination approximately 47% of children were normal, while as rest were suffering from dispigmentation of hair, moon face, xerosis of skin cheilosis, magenta tongue, spongy bleeding gums, oedema, conjuctival xerosis, and mottled dental enamel. The findings indicated that nutritional intake was deficient for all nutrients when compared to, Recommended Daily Allowances Chart (RDA) for all age groups which may be linked to poor planning of menus in orphanages.


2018 ◽  
Vol 69 (10) ◽  
pp. 2913-2915
Author(s):  
Daniela Jumanca ◽  
Anamaria Matichescu ◽  
Atena Galuscan ◽  
Laura Cristina Rusu ◽  
Cornelia Muntean

This experimental study aims to analyse the effectiveness of various materials used in demineralisation of dental enamel. This work aims to create a mechanical bond by filling the pegs with sealing material. In order to achieve this goal, five teeth were compared using different concentrations of orthophosphoric acid and exposure times. In this regard, five different tests were performed and the results were analysed using the SEM technique (scanning electron microscopy). These comparative analyses revealed that etching using 35% orthophosphoric acid for one minute and etching using Icon Etch for two minutes were the most effective.


Author(s):  
Sérgio Spezzia

Resumo Doença celíaca (DC) consta de desordem inflamatória crônica autoimune, que desencadeia reação autoimune na região do intestino delgado. As modificações ocasionadas pela DC na mucosa do intestino delgado possuem reversibilidade, ao passo que orienta-se os pacientes a não ingerir mais alimentação que contenha o glúten. Deve ser adotada também como medida a averiguação das bulas dos remédios, no intuito de verificar se os mesmos contém traços de glúten em sua fórmula. Existem inúmeros pacientes assintomáticos, o que dificulta a determinação diagnóstica e sabe-se que caso não se proceda ao diagnóstico e ao tratamento da DC em tempo hábil pode haver complicações indesejáveis. O objetivo do presente artigo foi averiguar acerca das manifestações bucais ocorridas em pacientes doentes em decorrência da presença da DC. As principais manifestações orais da DC que podem ocorrer envolvem hipossalivação; glossites; defeitos de esmalte; úlceras aftosas recorrentes; estomatites; aftas; manchas por insuficiência ou por excesso de cálcio, dentre outras. O conhecimento e a conscientização prévia pelos cirurgiões dentistas acerca das repercussões bucais acarretadas pela possível presença da DC em seus pacientes é de fundamental importância para o aprimoramento diagnóstico e para a adoção de condutas odontológicas apropriadas. Palavras-chave: Doença Celíaca. Dieta. Diagnóstico Precoce. Hipoplasia do Esmalte Dentário. Keywords: Celiac Disease. Diet. Early Diagnosis. Dental Enamel Hypoplasia.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3072
Author(s):  
Riccardo Monterubbianesi ◽  
Vincenzo Tosco ◽  
Tiziano Bellezze ◽  
Giampaolo Giuliani ◽  
Mutlu Özcan ◽  
...  

This study aimed to evaluate two hydrogen peroxide (HP)-based at-home bleaching systems in order to analyze whether nano-hydroxyapatite (nHA) addition may represent a reliable and safe solution for tooth whitening without altering dental microstructure and hardness. Human third molars (N = 15) were treated with two bleaching agents, one containing 6%HP (6HP) and the other 6% HP nHA-enriched (6HP-nHA) with average particle diameter ranging from 5–20 nm. Their effects on enamel were assessed using a spectrophotometer, Vickers microhardness (VMH) test and Scanning Electron Microscopy (SEM), comparing the treated groups with the non-treated control group (CTR). Color analysis revealed improvement in whiteness in both groups compared to CTR. VMH test results showed no differences among the groups. SEM analysis highlighted no evident changes in the enamel microstructure of tested groups compared to CTR. At high magnification, in 6HP group, a slight increase in irregularities of enamel surface morphology was observed, while 6HP-nHA group displayed removal of the aprismatic layer but preservation of the intact prismatic structure. These results suggest that the 6HP-nHA agent may be recommended to provide reliable whitening treatment, without damaging the enamel micromorphology and hardness.


Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 549 ◽  
Author(s):  
Bruna Sinjari ◽  
Gianmaria D’Addazio ◽  
Martina Bozzi ◽  
Manlio Santilli ◽  
Tonino Traini ◽  
...  

The aim of this in vitro study was to evaluate the enamel surface topography after treatment with three air polishing powders: Glycine (A), erythritol (B), and sodium bicarbonate (C) (Air Flow Soft, Plus and Classic powders, EMS Electro Medical Systems S.A., Nyon, Switzerland). Fifteen extracted incisors were randomly divided into three groups of five teeth each, A, B and C, respectively. The teeth were blocked in plaster bases, washed, dried and half-covered with polytetrafluoroethylene strips before treatment. In this way, each half-treated dental element became test and control of itself. Comparative statistical analysis of Rq (geometric average of the deviations occurring in roughness profile) was performed. The scanning electron microscope (SEM) analysis showed different degrees of surface roughness between the groups, decreasing after treatment. In addition, a statistically significant reduction p < 0.05 was present in group C (Rq mean non-treated 108.17 µm, 95% CI: 97.29–124.01 and Rq mean treated 86.78 µm, 95% CI: 80.63–93.70). A decrease in surface roughness post-treatment was not observed in group A and B. Therefore, it may be concluded that the air flow powders tested herein can be used on dental enamel to reduce the surface roughness due to function and the action of dental therapies.


1997 ◽  
Vol 42 (3) ◽  
pp. 243-250 ◽  
Author(s):  
T. Attin ◽  
U. Koidl ◽  
W. Buchalla ◽  
H.G. Schaller ◽  
A.M. Kielbassa ◽  
...  
Keyword(s):  

2007 ◽  
Vol 86 (1) ◽  
pp. 69-72 ◽  
Author(s):  
M. Kida ◽  
Y. Sakiyama ◽  
A. Matsuda ◽  
S. Takabayashi ◽  
H. Ochi ◽  
...  

Amelogenesis imperfecta (AI) is a hereditary disease with abnormal dental enamel formation. Here we report a Japanese family with X-linked AI transmitted over at least four generations. Mutation analysis revealed a novel mutation (p.P52R) in exon 5 of the amelogenin gene. The mutation was detected as heterozygous in affected females and as hemizygous in their affected father. The affected sisters exhibited vertical ridges on the enamel surfaces, whereas the affected father had thin, smooth, yellowish enamel with distinct widening of inter-dental spaces. To study the pathological cause underlying the disease in this family, we synthesized the mutant amelogenin p.P52R protein and evaluated it in vitro. Furthermore, we studied differences in the chemical composition between normal and affected teeth by x-ray diffraction analysis and x-ray fluorescence analysis. We believe that these results will greatly aid our understanding of the pathogenesis of X-linked AI.


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