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Classification of composite resin material based on filler size,viscosity,matrix,polymerization methods

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  CLASSIFICATION OF COMPOSITE RESIN MATERIAL:   I)BASED ON FILLER SIZE: HOMOGENEOUS- MACROFILLED,MINI,MICROFILLED HETEROGENEOUS HYBRID  MACROFILLED: The original composite resin material were macrofilled Material have high level of loading Particle size is 4 -40 microns  Advantage:  Strong as high loading Disadvantage: Filler particle harder than abrasive  When polished : soft matrix was worn away,exposed large,hard filler It becomes rough therefore they are not polishable It has poor wear resistance  MICROFILLED COMPOSITE RESIN : Why was microfilled composite resin discovered? Due to poor polishability of microfilled composite resin Material have uniform filler particle size 0.04 micron,low level of filler loading  Low level of filler loading  Advantage: Very polishable ,hence excellent esthetics Disadvantage: Low modulus of elasticity ,therefore not suitable for stress bearing area. Contra-Indication: Class 4 restoration Restoration of posterior teeth Evidence indicate that microfill

Filling root canals in 3 dimensions- Endodontic techniques

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  OBTURATION TECHNIQUE : OBTURATION: Three filling of entire root canal system According to american association of endodontist : obturation is the method used to fill and seal a cleaned and shaped root canal using a root canal sealer and core filling material OBJECTIVE: Substitution of an inert filling  To eliminate all avenue of leakage from oral cavity Seal iatrogenic causes Same shape as root morphology Radiographic appearance - dense 3D filling  When to obturate root canal? Obturation after obtaining negative culture test  Absence of foul odour Lack of periapical sensitivity No excessive exudate from canal Obturated when tooth is asymptomatic when root canal is reasonable dry It should be sterile ,or easily and quickly sterilised immediately before insertion  CLASSIFICATION OF OBTURATING MATERIAL  ACCORDING TO GROSSMAN: PLASTIC - Gutta percha,resilon solid- silver point,stainless steel cement and paste- hydron,mineral trioxide aggregate,calcium phosphate,gutta flow  Requirement f

Culture media and medium- microbiology learn it easy with stencildent

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  CULTURE MEDIUM AND CULTURE MEDIA  CULTURE MEDIUM: DEFINITION: A chemically prepared solid /liquid substance used to support the growth of microorganism Uses :  To provide nutrition To provide space To provide growth To increase population To handle stress To differentiate species  COMPONENTS: 1) NITROGEN SOURCE- Amino,protein extract,peptone 2) Growth factor- Blood serum,meat,yeast extract 3)Energy- Sugar,alcohol,carbohydrate 4)Buffer - Maintain ph ,phosphate,acetate  5) Salt- Enhance growth,phosphate ,sulfate,magnesium SELECTIVE AGENTS: CHEMICAL ANTIBIOTICS INDICATOR DYE GELLING AGENT :  Act as solidifying agent  agar ,gelatin- agents CULTURE MEDIA  Culture media is required to grow organism from infected material to identify the causative agent It contains: water,vitamin,mineral,growth factor,blood,serum,agar,peptone   TYPES : SIMPLE COMPLEX SPECIAL: ENRICHED,ENRICHMENT,SELECTIVE,DIFFERENTIAL,INDICATOR,TRANSPORT,SUGAR  SYNTHETIC ANAEROBIC : DEHYDRATE  SIMPLE: Nutrient broth - pepto

Age determination in forensic odontolgy

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 DENTAL AGE ESTIMATION - FORENSIC ODONTOLOGY PART 2 Age estimation using dentition may be grouped into three phases  1)Aging  in prenatal and early postnatal 2) age estimation in children and adolescents 3) age estimation in adults  AGEING IN PRENATAL,NEONATAL AND EARLY POSTNATAL: A)NEONATAL LINES: Primary tooth germ - 7 weeks in utero Enamel formation of deciduous teeth completes by 1st year. permanent 1st molar ( germ formation )  is 3.5 -4 months in utero  because of above said features this estimation in this group is very accurate  Neonatal lines - indicator  I f neonatal lines present implicates  -LIVE BIRTH ,in case of stillbirth ( loss of pregnancy ) - absent legal implication in case of infanticide  AGE ESTIMATION IN CHILDREN AND ADOLESCENT:  T ooth eruption:  deciduous - 6 months to 2.5 years  permanent - starts at 6 years ( eruption of 1st molar) Method to determine age in children and adolescents : VALUE OF 3RD MOLAR SCHOUR AND MASSLER METHOD TOOTH CALCIFICATION DEMIRJIAN&#

how do forensic odontologist use dental record to identify people?

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  FORENSIC ODONTOLOGY -PART 1 Forensic odontology : Application of dental principle to legal issue Dental identification : COMPARATIVE METHOD POST MORTEM DENTAL PROFILING COMMON REASONS FOR IDENTIFICATION OF FOUND HUMAN REMAIN? CRIMINAL: Investigation to a criminal death cannot begin until the victim has been positively identified SOCIAL: its society duty to preserve human rights  Marriage : Individuals from many religious background cannot remarry unless their partners are confirmed deceased Closure: the identification of individual missing for prolonged period can bring sorrowful relief to family members  1) COMPARATIVE METHOD: A) ORAL AUTOPSY Rigor mortis -muscle stiffness ,myotomy to cut open the muscles Obtaining dental records: Dental charts,radiograph,cast  To see if there is any bite mark in the body To take salivary swab - source of DNA Photograph,radiograph Check for missing records  B) RUGOSCOPY ( POST   MORTEM PROFILING) Rugae help in gender ,race ,it also helps in both

PROTON PUMP INHIBITOR - MECHANISM OF ACTION ,USES

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  PROTON PUMP INHIBITOR  Peptic ulcer occurs due to the imbalance between acid -pepsin secretion and mucosal defense factor  Proton pump inhibitor act by inhibiting the gastric acid secretion  Its a efficacious inhibitor omeprazole is a drug that's commonly use MECHANISM OF ACTION: The parietal cells of stomach secrete :H + with the help of enzyme H+K+ATPase present in the plasma membrane Omeprazole and other proton pump inhibitor are produrg get activated in the acidic environment of the stomach to sulfenamide which binds covalently with H+K+ATPase   The binding is irreversible Single dose can almost (95%)inhibit gastric secretion Acid secretion start only after new H+K+ATPase enzyme is synthesises . Ulcer heals rapidly even in resistant cases. PHARMACOKINETICS; Given as enteric coated granules to avoid degradation by acid in stomach Effect of 1 dose remains for 2 to 3 days Microsomal enzyme inhibitor Increases level of benzodiazepine,warfarin  ADVERSE EFFECT : Headache Nausea Pai

Peptic ulcer - Classification,mechanism of action,antacid

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  PEPTIC ULCER  - Part 1  Peptic ulcer is result from imbalance between acid pepsin secretion and mucosal defense factor Stomach secrete 2.5 litre of gastric juice daily MECHANISM OF ACTION: Chief cell secrete pepsinogen Parietal  cell secrete   hydrochloric  acid and intrinsic factor Gastric acid secretion regulated by  Acetylcholine   - muscarinic  receptor Gastrin - g receptor Histamine- h2 receptor Acetylcholine and gastrin act on parietal  cell Act indirectly on enterochromaffin cells releasing  histamine Mucosa secretes mucus  which forms the protective layer ,bicarbonate and prostaglandin Prostaglandin  stimulate mucus and bicarbonate that leads to vasodilation  and thereby inhibit gastric  secretion  CLASSIFICATION : DRUG FOR PEPTIC ULCER : A) GASTRIC ACID SECRETION INHIBITOR : H2 antihistamine - CIMETIDINE,RANITIDINE Proton pump inhibitor - OMEPRAZOLE,LANSOPRAZOLE B) GASTRIC ACID NEUTRALIZER : Systemic - sodium bicarbonate,sodium citrate Non systemic - magnesium hydroxide,calc