Dentistry Flashcards
Who should have Antibiotic Prophylaxis before dental procedures?
Patients with cardiac conditions such as prosthetic heart valves, who have had previous endocarditis, cardiac transplant patients, or who have congenital heart disease (Either repaired or unrepaired).
When is antibiotic prophylaxis recommended?
Before any dental procedure that involves the manipulation of the gingival (gum) tissue, periapical region of teeth, or oral mucosa.
i.e. extractions, cleanings, fillings, root canals.
When is antibiotic NOT recommended?
Routine anesthetic injection through noninfected tissue
Taking dental x-rays
Placement of removable prosthesis
Adjustment/placement of orthodontic appliances
Bleeding from trauma to lips/oral mucosa
What medication is used for antiobiotic prophylaxsis?
Single oral dose 30-60 minutes prior to appointment of amoxicillin (2g for adult; 50 mg/kg for child).
Can use Clindamyacin, Ampicillin, Cefazolin if patient is allergic to pencillins.
Dental Caries
Infectious microbiological disease of the teeth that results in localized dissolution and destruction of the calcified tissue.
What 3 things are necessary for dental caries to occur?
Teeth
Bacteria
Carbohydrate (sugar)
Also, time for the bacteria to grow and devour the carbs. Brushing disrupts this, so dental caries can be prevented.
What agent is the main cause of Dental Caries?
Strep. mutans: gram positive alpha hemolytic cocci. Facultative anaerobe.
Acid producer and acid tolerant.
Produces glutans from sucrose whcih act as a matrix for the bacteria on enamel surface.
What agent causes root caries?
Actinomyces: gram positive filamentous rod that resembles a fungi.
Dental Plaque
A gelatinous mass of bacteria and its food source adhering to the tooth surface.
The accumulation of plaque on teeth is a highly organized and ordered sequence of events.
Removed during brushing/flossing.
Sequence Leading to Dental Plaque
- Bacteria produce acid
- Acid dissolves the calcium phosphate matrix of enamel.
- Bacteria invade dentin.
- Dentin is dissolved.
- Pulp tissue is invaded (nerves/vessels)
- Irreversible infection of pulp tissue
When does Lactobacillus cause dental carries?
After streptococci invade; allows more organisms to adhere. As the bacteria multiply in the plaque, the flora environment is more adequate for anaerobes: the S. mutans creates and environment for itself via making glutans and acid.
A patient with dental caries was prescribed an antibiotic, which successfully took care of the gram + aerobes causing the cavity. However, a week later, the patient presented with a black tongue described as “hairy”. Why?
Fungi are not affected by long-term penicillin use.
Actinomces
Anaerobic acid producing filamentous bacteria that resembles fungus. It thrives at the gingiva when root surface is exposed (generally in older patients with natural gum regression) and can cause peridontital disease.
Lactobacillus
Rod shaped anerobic acid producing and acid tolerant baccteria present in later stages of caries.
Which layers are most susceptible to dental caries?
The dentin. Enamel is resistant, but once infection reaches the dento-enamel junction, it generally spreads to the pulp.
Treatment of Dental Caries
Remove infected enamel and dentin and replace with synthetic so that it can be cleansed by the patient.
Self-repair of teeth
As acid dissolves calcium phosophate out of enamel, recalcification also occurs. Brushing and flossing allow this to occur because it interrupts dental carry formation.
A patient comes to you complaining that she has been getting cavities ever since starting a depression medication. How do you explain this to her?
A side effect of the meds is dry mouth, which decreases saliva production and interrupts the remineralization process. Advise her to take good care of her teeth.
Prevention of Dental Caries: Fluoride
Topical in toothpaste
Water supply (Easiest/most effective)
Fluoride pills if there is no F in the water.
Action of Fluoride
Absorbed into enamel and aids in recalcification if taken orally. Also makes enamel less soluble in acid.
If internally, becomes part of dentin and enamel matrix.
Xylitol
A sugar alcohol derived mainly from birch and other trees. It is associated with decreased stretopcoccus mutans in saliva and plaque.
Chlorhexidine
Antispetic agent use of rinse in high risk patients decreases bacterial count for hours. Useful in peridontal/gum disease.
Make sure to lift the lip when examining teeth, especially in kids.
Look for inflammation, ulceration, lumps and bumps.
A healthy mouth is:
Pain free
Gums are pink or brown with knife-edged gum triangles
Gums don’t bleed, are firmly attached to bone, and are dimpled like an orange peel
No dark spots or broken teeth