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Dental Pathology and Microbiology. Unit 1 Classifications of Microorganisms. Unit 1. Definition: Microbiology Micro Bio Ology Oldest form of life Most are Beneficial Only a few are harmful. Why do we study Microbiology?. The world we live in….. People live longer
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Dental Pathology and Microbiology Unit 1 Classifications of Microorganisms
Unit 1 • Definition: Microbiology • Micro • Bio • Ology • Oldest form of life • Most are Beneficial • Only a few are harmful
Why do we study Microbiology? The world we live in….. • People live longer • Diseases are now controlled • Healthier Food • Better conditions • Medical Advances • Environmental advances
Microbiology & Medicine • Science MUST be ready to face the challenge • Knowledge of transfer of microorganisms can reduce spread of disease • Knowledge of immunity can reduce disease • Knowledge of sterilization & disinfection procedures will reduce or prevent spread of disease • Not all microorganisms are harmful, some are even helpful
Theory of Spontaneous Generation • Mold on food • Spoiled drinks & spoiled food • Theory was = caused by devil or curse of God • Seemed to be no physical cause • Some scientists attempted to disprove theory • “Catching” diseases spread by contact with humans and animals
Leeuwenhoek • Dutch merchant & Amateur scientist • Hobby of grinding lenses to observe microbes • “Animalcules” = small moving objects • Drew pictures and wrote volumes • Early lenses led to early microscopes • Took scrapings from teeth to observe appearance • Referred to as Father of Microbiology
Pasteur • Professor of chemistry in France • Experimented with heating liquid • Process of pasteurization • Process used for wine, beer & Milk • Food canning process • Discovery labeled “Germ Theory of Disease” proved that airborne bacteria was the cause of some diseases
Golden Age of Microbiology • Many new discoveries 1880-1910 • Communication was limited • Scientists and doctors in all countries were working on theories • Numerous causes of disease & death; patients died in hospitals; women died in childbirth • Physicians wore street clothes in surgery
Holmes • Physician in Boston • Studied “child bed” fever in new mothers • Suggested nurses and physicians wash hands
Semmelweis • Hungarian doctor • Explored use of antiseptics with washing • Number of deaths were reduced • Both Holmes & Semmelweis were working on same experiments in different countries
Lister • English Surgeon • Set out to prove that wound infection due to microbes • Tried carbolic acid (PHENOL) • Soaked surgical dressings & instruments & tables • Asked staff to use phenol on hands after washing • Established aseptic techniques
Koch • German biologist & physican • Proved ‘specific bacteria causes disease’ • Developed rules • 1. Organism must be present • 2. Organism must be isolated • 3. Organism must produce disease in another • 4. Organism must be recovered
Miller • American dentist & researcher • Theory: connection between bacteria, carbohydrates & tooth disease • BACTERIA + FOOD = Produce Acids • Acids on teeth = cause decay (cavities)
Review • Leeuwenhoek – • Pasteur – • Koch – • Lister • Holmes - • Semmelweis - • Miller -
Normal Flora • Resident microbial population of human body • Microorganisms live (reside) in and on body * Always present
Activities of Microbes • Bacteria in soil converted to usable nutrients • Bacteria cultured to make vinegar, vitamins, antibiotics • Bacteria or fungi used to pickle cucumbers; • Produce cultured dairy: yogurt & sour cream • Yeast makes bread dough & used in beer production
GROUPS OF MICROORGANISMS • BACTERIA • VIRUSES • FUNGI – Yeasts & Molds • PROTOZOA • Bacteria & viruses are concern in dental office • Some fungi can cause dental problems
BACTERIA • Small cells • Divide by binary fission • SHAPES: • COCCI • BACILLI • SPiRILLA • VIBRIOS
Bacteria • Grow in COLONIES • Bacterial growth = increase in cell numbers • Cells divide by BINARY FISSION • Division of cells occurs every 20-30 minutes • Some bacteria have ability to grow • Some bacteria do not survive
Growth Requirements of Bacteria • Temperature • Acidity • Nutrients • Oxygen Metabolism • Water
Bacteria • Culturing Bacteria – grow bacteria in laboratory • Nutrient base called medium • Preventing growth – changing requirements • Bacteriostatic • Bacteriocidal
Infections/Diseases from bacteria • TUBERCULOSIS • DIPHTHERIA • PERTUSSIS • TETANUS • STREPTOCOCCAL Infections (caries) • STAPHLOCOCCAL Infections
FUNGI: Yeasts & Molds • Larger than bacteria • Disease: Candidiasis (known as thrush) • Found inside mouth • Cannot be killed with antibiotics • Usually cause problems after use of too much antibiotics
VIRUS • Smaller than bacteria • Have many shapes • Cause disease by changing cells • Cannot be killed with antibiotics • Some antiviral drugs • Best approach is immunization or Infection Control Procedures
Viral Diseases • Measles, Mumps, Rubella • Poliomyelitis • Chicken Pox (Varicella) • Common Cold • Influenza • Herpes Simplex • Hepatitis
VIRAL NO PPE??? • Herpetic Whitlow- Herpes on hand • Herpetic conjunctivitis- Herpes of eye
Live in bloodstream, mouth & digestive tract Contaminated drinking water Gum disease (Periodontal disease) Parasites – cannot live outside a host Diseases are Typhus & Rocky mountain fever Protozoa Rickettsiae
THE END • Grandpuppies