《d6521 e1 l05 antibiotics_part2 [20101001]课件》由会员分享，可在线阅读，更多相关《d6521 e1 l05 antibiotics_part2 [20101001]课件（53页珍藏版）》请在金锄头文库上搜索。
1、Antibiotic Chemotherapy for Oral & Maxillofacial Surgery,History of Antibiotics-Early History,Ayurveda-Oldest medicine system (over 5000 years old) used Sesame paste, Honey, Skin from the stem of many antiseptic herbs e.g. Neem (azadirachta indica),Turmeric root etc. In 3500 BC the Sumerian doctors
2、would give patients beer soup mixed with snakeskins and turtle shells. (yummy!) Babylonian doctors would heal the eyes by using an ointment made of frog bile and sour milk. The Greeks used many herbs to heal ailments.,Modern History,Louis Pasteur Sir Alexander Fleming-Penicillin 1929 accident Domagk
3、- discovers synthetic antimicrobial chemicals (sulfonamides). Late 1940s through the early 1950s, streptomycin, chloramphenicol, and tetracycline were discovered and introduced as antibiotics Antibiotic era,Overview,Antimicrobial compounds Antiviral Antifungal AntibacterialSelective Toxicity: the dr
4、ug can be administered to humans with reasonable safety while having a marked lethal or toxic effect on a specific microbe.,Decision to Use Antibiotics,Would you like to treat this patient with antibiotics,John a 30 year old patient has painful tooth #29 but no swelling , no trismus or increase in t
5、emperature. His general health is Good. Would you administer antibiotics to him following an extraction, WHY ?,Principles of appropriate Antibiotic use,Evaluate the patient carefully and in this order: Severity of Infection Patients host defenses Treating the infection surgically (I&D) Treating with
6、 antibiotics,Indications of Antibiotic Use,Temperature 101F with malaise Spreading cellulitis Chronic infection resistant to previous TX Anatomical space involvement Trismus Lyphadenopathy Pt with co-morbidities Acute pericornitis, osteomyelitis, ANUG, etc,Antibiotics Use Not Indicated,Minor, chroni
7、c, well localized abscess Toothache Periapical abscess Dry socket Multiple extractions in healthy patient Surgical extraction (drill and sutures) Mild pericoronitis Drained alveolar abscess,Selection of Antimicrobial Agents,Rational Antibiotic Therapy:,Is the ideal method for deciding on which antib
8、iotic to administer, and is based on: C&S of organisms involved Site of infection Safety of agent Patients status Cost of therapy,Cost,Empirical Antibiotic Therapy:,Broad-spectrum antimicrobials can be administered on a “educated guess” basis, considering:- Site of infection- Most probable pathogens
9、- Antibiotic sensitivity pattern- C&S is not always cost and time effective,Cidal vs. Static,Bactericidal Agents: Kills bacteria and reduces the total number of viable organisms.Bacteriostatic Agents: Arrest the growth and replication of bacteria, thus allowing the host immune system to complete pat
10、hogen elimination.,Bactericidal vs. Bacteriostatic,Prefer Bactericidal to Bacteriostatic Bactericidal disrupts the cell wall synthesis-killing the bacteria Less reliance on host resistance Drug works faster than static More flexibility with dosage intervalBacteriostatic inhibits the RNA synthesis/re
11、production Inhibit growth and reproduction of bacteria Help the host defenses to take over,Therapeutic Spectra,Refers to a particular drugs species of organisms affected. Antimicrobial agents are categorized:-broad-spectrum: acts against both Gram- positive and Gram-negative bacteria. -narrow-spectr
12、um: effective against only specific families of bacteria.,Therapeutic Spectra Examples of Antibiotics,Narrow spectrum Penicillin Cephalosporin (1st generation) Clindamycin Metronidazole,Broad spectrum Amoxicillin Augmentin (Amoxicillin with clavulanic acid) Azythromycin Tetracycline Moxifloxacin,The
13、rapeutic Spectra,Combination Therapy,The use of more that one agent is not advisable, in most dental situations because: Risk of increased side-effects Competitive antagonism of agents Co$t However, there are certain situations where this is appropriate: Adding Metronidazole to Penicillin that the p
14、atient is already taking.,Clinical Scenario,Pt was I&Dd and given a Rx of Pen VK 500mg on Mon. due to significant vestibular swelling status post 5 days extraction of #19.Pt. returns to clinic today (Fri.) with diffuse indurated swelling on his left submandibular space.What TX should be considered.,
15、Why is TX failing,Consider if no response within 48 hours: Inadequate I&D Inappropriate antibiotic therapy Presence of local factors Impaired host response Poor patient compliance Poor perfusion Unusual pathogen and/or no infective etiology.,Antibiotic Resistance,This is a major problem for patients
16、 and healthcare providers in the hospital setting.Resistance develops when progeny of resistant bacteria proliferate via selective advantage.As long as the antibiotic is being taken, this proliferation will continue.,Types of Antibiotic Resistance,Primary Resistance: Organism is naturally resistant to the drug.Acquired Resistance: Mutation within the same species or gene transfer between different species (plasmids).Cross-Resistance: Resistance to one drug confers resistance to another similar drug.,
