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16 Cards in this Set
- Front
- Back
biomaterials
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man made materials that are used to replace tissues or that function in intimate contact with living tissues
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dental materials
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are biomaterials used in or around the oral cavity
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biologic materials
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oral tissues are biologic tissues.
all oral tissues must function in the hostile environment of the oral cavity. |
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enamel
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resist compressive forces
weak resistance to bending and other forces when food ground by molars enamel is supported by dentin enamel will disolve in oral fluids if the pH is to acidic; dental carries will be the result |
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dentin
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bulk of the tooth
cushion provide strength to resist complex forces when biting more susceptible than enamel to acidic attack |
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pulp
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provides nutrients to the dentin
responds to stimuli with pain or sensitivity |
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periodontium
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supports the tooth: stable dynamic position
periodontal ligament,cementum,and alveolar bone. provides feedback regarding force placed on the tooth. |
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gingivitis tissue
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seal out many noxious agents; chemicals,and microbes from gaining access to the periodontium and deeper tissues.
surround and attach to teeth/barrier oral cavity is more like outside. biomaterials placed in oral cavity have different requirements f t I'm devices implanted inside. |
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restrictions on material use
the nature and size of oral cavity restrict the use of materials |
a.)biting forces/may fracture teeth &replacement materials
b.)degradation of: .materials such ascorrosion of metal .teeth such as dental carries c.) temp. changes that cause restoration to contract and expand differently than teeth,causing leakage around restoration and tooth sensitivity d.)biocompatibility: lack of harmful effects to the patient. e.)esthetic demands of the patient |
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effects of dental materials and oral environment on each other
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orthodontic appliances make the patient more susceptible to gingivitis inflammation and carries
yeast or other microbes may colonize a denture may cause it to become foul smelling |
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1700's
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Ivory:carved
Porcelain: fired into tooth shapes Wax & Gypsum: impressions and models Zinc Oxide-Eugenol & Zinc Phosphate: fillings and cement |
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1800's dintistry was becoming scientific based discipline
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Amalgam: silver filling material
porcelain :inlay and crowns |
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base and liner
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using under a metal restoration between pulp and and the filling can reduce or eliminate sensitivity to cold and hot foods and beverages.
Base: strength and thermal insulation: greater bulk: restore part of missing tooth structure and provide thermal insulation. Liner: thin layer of material to protect underlying dentin from chemical irratation |
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dental implants
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screws or posts that are anchored to alveolar bone that protrude through the gingiva into the oral cavity.
used to replace the root portion of lost teeth both inside and outside the body |
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Direct Restorative: cavity preparation
material is like putty that sets and become hard. |
a.) amalgam : liquid mercury with powdered metals :directly placed and carved
b.) Composites: esthetic material that polymerize in the mouth : paste placed in preparation and set by chemical reaction c.) Glass ionomers & other cement : motor like materials :set by acid base chemical reaction. |
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Indirect restoration fabricated outside the mouth/ could harm oral tissues
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a.) Gold Crowns and inlays: made by melting metals and pouring (forcing)into molds
b.)Ceramic: many techniques : ceramic powder is fired at high temp. and becomes solid object example: porcelain crown c.) Indirect Restorative Polymers: plastics processed or cured at elevated temp. under high pressure. example: pink gingival portion of a denture. |