Human Teeth – Structure and Composition of Dental Hard Tissues and Developmental Dental Defects [Working Title]

2021 ◽  
Keyword(s):  
Human Teeth ◽  
Dental Hard Tissues ◽  
Hard Tissues

Variation in the Changes Induced by Different Forms of Tobacco in Dental Hard Tissues-A SEM-EDAX Study

2011 ◽  
Vol 53 (4) ◽  
pp. 348-355
Author(s):  
Thakare Eesha ◽  
Chaudhary Minal ◽  
Gawande Madhuri ◽  
Wadhwan Vijay ◽  
Gadbail Amol
Keyword(s):  
Dental Hard Tissues ◽  
Hard Tissues

Primary Teeth and Hair as Indicators of Environmental Pollution

2016 ◽  
Vol 40 (2) ◽  
pp. 152-155 ◽  
Author(s):  
TE Shishniashvili ◽  
NN Suladze ◽  
VV Margvelashvili
Keyword(s):  
Environmental Pollution ◽  
Toxic Elements ◽  
Chemical Elements ◽  
Epidemiological Survey ◽  
Essential Elements ◽  
World Health ◽  
Dental Tissues ◽  
Dental Hard Tissues ◽  
Hard Tissues ◽  
Health Organization

Objectives: To study the influence of environmental pollution on the mineralization of dental hard tissues by using biosubstrates: teeth and hair. :Study design: At the first stage epidemiological survey was conducted in polluted and less polluted areas of Tbilisi (Georgia). We studied 525 children aged 3 and 4 years. Caries prevalence and intensity was defined by the methodology of World Health Organization. At the second stage the chemical elements content was studied in hair and teeth hard tissues of 24 children by X - ray fluorescent spectroscopy method. Results: The prevalence of dental caries in the polluted region was 46%, caries intensity − 1.92 (± 2.842). In the less polluted region prevalence was 37%, caries intensity − 1.47 (± 2.571). These data are statistically reliable (p < 0.05). The study of hair and tooth tissues showed that the toxic elements (Pb, Hg, Sn, Ti) content in these tissues was higher in environmentally unfavorable than in favorable conditions. Conclusion: Hair and dental tissues can be used as indicators of environmental pollution. Our survey showed that toxic elements content in dental hard tissues was higher and the level of essential elements was less in polluted than in less polluted areas of Tbilisi.

A Study of the Mechanical Role of Enamel and Dentin in Human Teeth

2012 ◽  
Author(s):  
Keyoung Jin Chun ◽  
Hyun Ho Choi ◽  
Jong Yeop Lee
Keyword(s):  
Surface Hardness ◽  
Mechanical Tests ◽  
Indentation Load ◽  
Bite Force ◽  
Compression Tests ◽  
Healthy Human ◽  
Human Teeth ◽  
Diamond Indenter ◽  
Dental Hard Tissues ◽  
Measured Hardness

The dental hard tissues of a tooth are combined of enamel and dentin together. The enamel protects the dentin and comes in direct contact with food during mastication. Bite force is expressed as compression force. The purpose of this study is to identify the primary roles of enamel and dentin during mastication by analyzing their mechanical properties and hardness. Healthy human teeth (age: 19.3 ± 4.1) were used as specimens for mechanical tests. The teeth, which underwent epoxy resin molding, were machine cut to make 10 enamel specimens, 10 dentin specimens and 10 enamel–dentin composite (ED) specimens of 1.2 mm × 1.2 mm × 3.0 mm (Width × Height × Length) in size. Compression tests were conducted using a micro-load system at 0.1 mm/min test speed. Teeth surface hardness (HV) was measured by a Vickers diamond indenter with a 300g indentation load. Data were obtained from 4 points on each enamel specimen and 4 points on each dentin specimen. The strain (%), stress (MPa) and modulus of elasticity (E, MPa) of the specimens were obtained from compression tests. The MAX. strain of the enamel, dentin and ED specimens were 4.5 ± 0.8 %, 11.9 ± 0.1 % and 8.7 ± 2.7 %, respectively. The MAX. stress of the enamel, dentin and ED specimens were 62.2 ± 23.8 MPa, 193.7 ± 30.6 MPa and 126.1 ± 54.6 MPa, respectively. The E values of the enamel, dentin and ED specimens were 1338.2 ± 307.9 MPa, 1653.7 ± 277.9 MPa and 1628.6 ± 482.7 MPa, respectively. The E of the dentin specimens was the highest and the E of the enamel specimens was the lowest, but the E values of all specimens was not significantly different in the T-test (P > 0.1). The measured hardness value of the enamel specimens (HV = 274.8 ± 18.1) was about 4.2 times higher than that of the dentin specimens (HV = 65.6 ± 3.9). Because of the values of MAX. stress and MAX. strain of the enamel specimens, the enamel specimens tended to fracture earlier than the dentin and ED specimens; therefore, enamel was considered to be more brittle than dentin and ED. Enamel is a harder tissue than dentin based on their measured hardness values. Therefore, enamel has a higher wear resistance, making it suitable for grinding and crushing, whereas dentin has a higher force function, making it suitable for abutment against bite force.

scholarly journals In Vitro Assessment of Erosive Effects of Some Common Soft Drinks on Dental Hard Tissues

2019 ◽  
Vol 23 (3) ◽  
pp. 132-140
Author(s):  
Enea Bitri ◽  
Lucian Petcu ◽  
Gabriela Mocanu ◽  
Doina Paula Balaban
Keyword(s):  
Weight Loss ◽  
Titratable Acidity ◽  
Soft Drinks ◽  
Hard Tissue ◽  
Time Exposure ◽  
Prolonged Time ◽  
Dental Hard Tissue ◽  
Dental Hard Tissues ◽  
Hard Tissues ◽  
Erosive Effect

Summary Background/Aim: The chemical nature of soft drinks is acidic, so they possess the capacity to cause hard tissue erosion. The aim of this study is to assess the potentially erosive effect linked to pH and titratable acidity of some common soft drinks on dental hard tissues in prolonged time exposure. Material and Methods: Seven types of soft drinks in Romanian market were selected for this study. The pH and Titratable acidity were determined. Twenty one human dental hard tissue specimens were immersed in 5 ml solution each for 336h. Every 48h weight loss was determined for each specimen and after 336h volume changes were calculated. Enamel microhardness was determined using a Microhardness Tester model HV-1000 and compared to normal enamel microhardness. Results: The pH values of beverages ranged from 2.37 to 3.1, showing no significant differences. All specimens presented color and surface texture modifications, weight loss and volume reduction. There were found significant differences between the mean values of weight loss and enamel microhardness of each type of specimens and type of beverages tested. The most representative findings were achieved by indentations done in specific zones on Sprite® immersed specimen. This result suggest that microhardness near the eroded surface was significant lower than in other zones. Conclusions: Data obtained have shown that all the soft drinks tested had an erosive effect, causing dental hard tissue dissolution. For prolonged time exposure titratable acidity may be a major predictor for erosive potential. Dental erosion may affect different levels of enamel causing decreased enamel microhardness.

scholarly journals ROLE OF THE ALKALINE FACTOR IN THE DEVELOPMENT OF DENTAL CARIES

2020 ◽  
Vol 15 (4) ◽  
pp. 5-10
Author(s):  
Bahlul Hamzaeb ◽  
Ayat Jafarova ◽  
Rena Huseynova ◽  
Rumia Abbasova ◽  
Shahla Yusubova ◽  
...  
Keyword(s):  
Dental Caries ◽  
Acetylcholinesterase Inhibition ◽  
Local Form ◽  
Negative Consequences ◽  
Theoretical Justification ◽  
Endogenous Factors ◽  
Dental Hard Tissues ◽  
Hard Tissues ◽  
Civilization Disease

Subject. This article analyzes existing theories about the prevalence and causes of dental caries, which is considered as a civilization disease. The crucial role of endogenous factors in the risk of caries, including a pulp and dental fluid, is noted. Data are given that acids do not actively participate in the process of demineralization, which is confirmed by numerous theoretical and hypothetical points. The role of some materials produced by dental industry based on this “pseudo-acidogenic” theory and used in the treatment of caries, as well as the false and negative consequences created by them in general, is analyzed, and adequate parallels are carried out. The purpose of the study was the theoretical justification of the key role of acetylcholine (the cholinomimetic mediator located on the Toms fibers) in the occurrence of dental caries. Methodology. Russian and foreign research works due to the etiology, prevalence and pathogenesis of dental caries were studied, and a comparative theoretical analysis of the available data on this issue was carried out. Results. Based on the results of numerous studies cited in the available literature and our studies, we performed an analysis of theoretical principles and substantiated the data that the process of demineralization occurring in dental caries cannot be caused by acids. Therefore, the only and decisive factor in the origin of the demineralization process is the occurrence of the process because of alkaline substances. Conclusions. Based on the studied references, we present the data that the most current theories of the etiopathogenesis of caries are imperfect in terms of solving the problem, which, in our opinion, requires further study of the process both of acetylcholine and the enzyme acetylcholinesterase inhibition in the local form and inside dental hard tissues.

Permanent and transient changes in the reflectance of CO2 laser-irradiated dental hard tissues at λ = 9.3, 9.6, 10.3, and 10.6 μm and at fluences of 1–20 J/cm2

1997 ◽  
Vol 20 (1) ◽  
pp. 22-31 ◽  
Author(s):  
Daniel Fried ◽  
Richard E. Glena ◽  
John D. B. Featherstone ◽  
Wolf Seka
Keyword(s):  
Co2 Laser ◽  
Dental Hard Tissues ◽  
Hard Tissues

Novel use of the CO2 laser on dental hard tissues: an SEM study

1997 ◽  
Author(s):  
Harvey A. Wigdor ◽  
Jeremy L. Gilbert ◽  
Doron Chomsky ◽  
Joshua Raif
Keyword(s):  
Dental Hard Tissues ◽  
Sem Study ◽  
Hard Tissues
Sign in / Sign up

Export Citation Format

Share Document