current use Abx Flashcards
Philosophy of Treatment via antimicrobials
Periodontitis:
* Is caused by bacteria
* A chronic disease
* Recurs or re-infects
Arrest the disease:
Alter the microflora to prevent reinfection
Maintain the disease in an arrested state
Effective Antimicrobial qualities
Comparative Dosage: Crevicular levels Versus Blood levels
* Cumulative oral dosage can have the problem
of? examples?
* Small dose of local delivery antimicrobial leads
to what crevicular levels?
* An example of a 250 mg tablet of Tetracycline
* Delivered systemically:
* Delivered locally:
- Cumulative oral dosage can have the problem
of side effects: Gastrointestinal problems or tolerance - Small dose of local delivery antimicrobial leads
to high concentration at crevicular level - An example of a 250 mg tablet of Tetracycline
- Delivered systemically: 2ug in peripheral blood level;
16ug in GCF - Delivered locally: 1600 ug in GCF
An antibiotic strength ?? times greater than
the systemic therapeutic dose may be required
to be effective against the bacteria residing in
plaque biofilms.
An antibiotic strength 500 times greater than
the systemic therapeutic dose may be required
to be effective against the bacteria residing in
plaque biofilms.
never use Abx in the absence of? why?
Never use antimicrobial agents in the absence of
mechanical debridement
Disrupt the biofilm physically to allow antibiotic
agents gain access to the periodontal
pathogens and inhibit biofilm formation
Chorhexidine
* %?
* toxicity/hyper sensitivity?
* Active against most?
* microbial resistance?
* Cannot reach?
* Sides effects?
- Chlorhexidine gluconate (CHX)(0.12-0.2%): the most studied and effective rinsing agent for plaque
inhibition and prevention of gingivitis - No systemic toxicity, rare hypersensitivity
- Active against most bacteria and fungi
- No microbial resistance reported
- Cannot reach the site subgingivally
- Sides effects: Taste alteration, tooth discoloration, increased supragingival calculus formation
stains of CHX
- Extrinsic brown discoloration on the teeth from an individual rinsing twice a day for 3 weeks with 0.2% chlorhexidine mouth rinse (Europe). Can be alleviated with 0.12% formulation (US).
- Beverages like tea, coffee and red wine will aggravate this superficial staining.** Can be removed **using prophy paste
CHX mechainsm
charge?
lower concetrations?
higher concentrations?
Chlorhexidine is a positively-charged molecule that binds to the negatively-charged sites on the cell wall; it destabilizes the cell wall and interferes with osmosis.
* Lower concentrations leads to increased permeability and leakage.
* Higher concentrations leads to precipitation of cytoplasmic contents inducing microbial cell death
substanstivity of CHX
- High substantivity
- Adhere to soft and hard tissues and then be released
over time - Slow release over 12 hours
Application of CHX
* As adjunct to regular oral hygiene methods during?
* challenged pts?
* Jaw?
* post surgery?
- As adjunct to regular oral hygiene methods during Phase I therapy (SRP) in high risk individuals (systemically compromised, refractory cases, etc)
- Mentally or physically challenged patients with low manual dexterity
- Jaw fixation, BRONJ
- 1st - 2nd week post surgery
Essential Oils
* Mouth rinse with?
* Antiplaque/ gingivitis index
* Side effects:
- Mouth rinse with eucalyptol, menthol, methyl salicylate, thymol
- Antiplaque effects and significant reduction in gingivitis index
- Side effects: Burning sensation and tooth staining
Side Effects essential oil rinses:
* Most anti-plaque rinses contains?
* Carcinogenic?
* Not recommended in?
- Most anti-plaque rinses contains alcohol as a vehicle to deliver antiseptic ingredients.
- Critical assessment of the literature does NOT support an association of alcohol‐containing mouth rinses and cancer.
- Not recommended in recovering alcoholics (craving for alcohol), in patients taking metronidazole or disulfiram (drug interaction).
essential oil rinse mechanisms?
* Cell wall?
* Inhibition of?
* Extraction of?
* Antiinflammatory action based on?
- Multiple mechanisms proposed
- Cell wall disruption
- Inhibition of bacterial enzymes
- Extraction of endotoxins derived from lipopolysaccharide (LPS) of Gram-negative bacteria
- Antiinflammatory action based on antioxidant activity
Hydrogen Peroxide
* Beneficial effects were seen with H2O2 levels above?
* Prolonged use of H2O2 decreased?
* Conflicting results was shown on the effectiveness of?
* Therapeutic delivery of H2O2 to prevent periodontal disease required?
- Beneficial effects were seen with H2O2 levels above 1%.
- Prolonged use of H2O2 decreased plaque and gingivitis indices.
- Conflicting results was shown on the effectiveness of 1.5% H2O 2 rinse.
- Therapeutic delivery of H2O2 to prevent periodontal disease required mechanical access to subgingival pockets. **Never use antimicrobial agents in the absence of mechanical debridement
**
Side Effects H2O2
* 3% H2O2 or less used daily showed?
* carcinogenic?
* ADA and FDA have concerns regarding?
* Possible?
- 3% H2O2 or less used daily showed occasional irritant effects: In small number of subjects with preexisting ulceration and When combined with high levels of salt solutions.
- In animal model, 30% H 2O2 was referred to as a co-carcinogen; 3% or less, no co-carcinogenic activity/adverse effects were observed.
- ADA and FDA have concerns regarding long-term use
- Possible co-carcinogen and impaired wound healing
Subgingival Irrigation
* when used as a monotherapy?
* Tissue invasive organisms?
- Significantly reduced monitored bacteria when
used as mono therapy, but not eliminated: Microbiota rebound to baseline within 1 to 8 weeks after short-term subgingival irrigation - Tissue invasive organisms doesn’t respond well.
- After 6 months of irrigation every 2 weeks with 3% hydrogen peroxide, limited success was achieved in reducing high concentrations of Actinobacillus actinomycetemcomitans
Properties of sub g irrigation
* Reaches the site with?
* Achieved ?% penetration in pockets of less than 6mm when tip was place ?mm apical to the margin.
* ?% penetration in deeper pockets when canula was placed ?mm apical to the margin.
Properties
* Reaches the site with a sufficient concentration
* Achieved 90% penetration in pockets of less than 6mm when
tip was place 1mm apical to the margin.
* 70-80% penetration in deeper pockets when canula was placed
3mm apical to the margin.
substantivity of sub g irrigation:
* Blood and proteins?
* retained to have an effect?
* 50% of a fluorescein labeled hydroxypropylcellulose gel injectedsubgingivally was washed out of pockets within?
* The gingival crevicular fluid is replaced in a 5 mm pocket how many times per hour?
* The half life of an antimicrobial irrigation concentration is ?
- Lack of substantivity
- Blood and protein can deactivate the drug
- The medicament may not be retained long enough to have an efficacious effect.
- 50% of a fluorescein labeled hydroxypropylcellulose gel injectedsubgingivally was washed out of pockets within 12.5 minutes
- The gingival crevicular fluid is replaced in a 5 mm pocket 40 times over an hour period
- The half life of an antimicrobial irrigation concentration is 1 minute.
subg CHX irrigation
- Single use to reduce the bacterial load; adjunctive use to gain the antiseptic effect
- A syringe and a jet irrigator with a cannula were equally effective.
- Low irrigation forces were effective
Betadine® subg irrigation
contents?
* Can be used how?
* Do not use when there is history of?
* Use with caution in ?
Betadine® (10% povidone-iodine and 1% free iodine)
* Can be used diluted as an irrigant
* Do not use when there is history of iodine sensitivity
* Use with caution in pregnancy and lactation to prevent inducing transient hypothyroidism in newborn
Local Antimicrobial Delivery
- LAD is the medicament placed in a periodontal pocket with a delivery system and released in a controlled manner, allowing minimum inhibitory concentration for 7 days.
LAD forms
- Chip/Slab/Strip/Film
- Injectable gel
- Fiber
- Microsphere
Ideal Properties LAD
* Effective against?
* Low risk of?
* systemic absorption?
* Biodegradable?
* Easy?
* Enhances?
- Effective against periodontal pathogens: Kill the pathogens effectively and Reach the site really well
- Low risk of bacterial resistance
- Low systemic absorption: Good concentration and substantivity
- Biodegradable
- Easy to use
- Enhances scaling and root planing
Indications for LAD
* When local sites with inflammation have not
responded to? example situations?
Always use as?
- When local sites with inflammation have not
responded to periodontal or maintenance therapy.
Examples: - Residual isolated pockets ≥5mm, not responding favorably to initial SRP with BOP at re-evaluation.
- Residual pockets after periodontal surgery.
- Recurrent isolated pockets ≥5mm with BOP at maintenance.
Always as adjunct therapy, never use alone.
PerioChip
* Perio-Chip®: bioresorbable polymer with what agent?
* Inserted in the pocket ?mm
* Release takes?
* Dissolves within?
* Significant improvement? when used with?
- Perio-Chip®: bioresorbable polymer with 2.5 mg
Chlorhexidine (film) - Inserted in the pocket ≥ 5mm
- Release takes 7days
- Dissolves within 7-10 days, does not require removal.
- Significant improvement in CAL when used with SRP
Atridox
active Abx?
* Delivered how?
* Controlled release over?
* Significant improvement in? used with?
* Do not use in patient with?
Atridox®: 10 % doxycycline hyclate gel
* Delivered subgingivally by canula to flow to the base of the pocket and adapt to root morphology
* Controlled release over 21 days
* Significant improvement in CAL when used with SRP
* Do not use in patient with hypersensitivity to doxycycline or
drugs in the tetracycline class.
arestin
* Abx?
* Bacteriostatic by?
* spectrym?
* Significantly reduced what in smokers?
- Arestin® : 1mg minocycline HCl in bioabsorbable microspheres
- Bacteriostatic by inhibiting protein synthesis
- Broad spectrum
- Significantly reduced red complex bacteria in smokers greater improvement in PD, CAL regardless of smoking status
actisite
* Abx/form
* Currently?
* Slow release over?
* application?
* Improve ? when combined use with SRP in ? months but no difference after?
- Actisite®: Non-resorbable, monolithic fiber contains 25% tetracycline-HCL powder
- Currently unavailable
- Slow release over 10 days
- Packed into the pocket and left in place for 7-12
days, need removal. - Improve PD, BOP, CAL when combined use with
SRP in 6 months but no difference after 5 years
LAD in Peri-implant Diseases
- Local Drug Delivery is not effective with implants
- May partially detoxify the implants but no long-lasting effects
- May be used as a step in implant recovery for regeneration of bone around implants in conjunction with grafting and GTR but there is still no evidence in literature
Laser Therapy
stands for?
* basic strucutures?
* color/ wavelength?
* The wavelength and other properties are determined primarily by?
“Light Amplification by the Stimulated Emission of Radiation”
- 3 basic structures:
1. An energy source,
1. An active lasing medium
1. Two or more mirrors that form an optical cavity or resonator - Monochromatic light with a single wavelength: The wavelength and other properties are determined primarily by the composition of an active medium
laser interactions with tissue
msot important is absorption
- Absorbing chromophores of laser therapy
- Intraoral soft tissue: Melanin, Hemoglobin, and Water
- Dental hard tissues: Water and Hydroxyapatite
Absorption
* 60°C< temperatures <100°C, proteins/ underlying tissues?
* When reaching 100°C, what occurs?
* At temperatures > 200°C, the tissue is?
* Light energy is converted into?
- 60°C< temperatures <100°C, proteins begin to denature without vaporization of the underlying tissue.
- When reaching 100°C, vaporization of the water within the tissue occurs (ablation)
- At temperatures > 200°C, the tissue is dehydrated and then burned, resulting in carbonization (undesirable effect).
- Light energy is converted into heat and photochemical effects occur depending on the water content of the tissues.
Absorption
* Different laser wavelengths have different? result of this?
- Different laser wavelengths have different absorption coefficients with respect to these primary tissue components, making the laser selection procedure-dependent
Diode Lasers
* Used in?
* Not effective for?
* Low-level laser has been recommended for?
- Used in soft tissue treatments
- Not effective for calculus removal despite it’s bactericidal efficacy
- Low-level laser has been recommended for pain reduction and enhancing wound healing due to its anti-inflammatory effects
Nd:YAG laser
* Highly absorbed by?
* Effective in?
* Used for ?
- Highly absorbed by the pigmented tissue
- Effective in cutting and coagulating dental soft tissues
- Used for nonsurgical sulcular debridement in periodontal disease control (Laser Assisted New Attachment Procedure (LANAP))
Erbium laser
* Laser of choice for treatment of?
* High affinity for?
* Highest absorption of what for any laser?
* Can be used for?
- Laser of choice for treatment of dental hard tissues
- High affinity for hydroxyapatite
- Highest absorption of water in any dental laser wavelengths
- Can be used for soft tissue ablation (water vaporation)
ideal properties of systemic Abx
- Effective against ALL periodontal pathogens
- Substantive and non-toxic
- Not in general use for other diseases
**No single antibiotic at concentrations achieved in GCF satisfies the above requirements
**
Adjunct Antibiotics
In phase I therapy
- Tetracyclines: Tetracycline, Doxycycline
- Penicillins: Amoxicillin, Augmentin
- Azithromicin
- Metronidazole
Tetracyclines
* High concentration in?
* spectrum bacteriostatic?
* Antimicrobial effect: highly effective against? but?
* tissue destruction?
* Photosensitivity?
* Doxycycline (DCN) compliance?
- High concentration in GCF (2-10 fold than serum)
- Broad spectrum bacteriostatic
- Antimicrobial effect: highly effective against A .
actinomycetemcomitans, but resistant strains are now common - Anti-collagenolytic effects: inhibit connective tissue destruction and promote repair
- Photosensitivity: severe skin burns
- Doxycycline (DCN): Better compliance because it can be given qd or bid
Penicillins
* A group of?
* spectrum?
* Affected by?: can be protected by?
* Augmentin?
* Up to ?% of humans are allergic to penicillins, Substitute?
* Can be used in combination with?
- A group of β-lactam antibiotics
- Characteristics
- Broad spectrum bactericidal
- Affected by beta-lactamases: can be protected by clavulanic acid
- Amoxicillin+clavulanic acid=Augmentin
- Up to 10% of humans are allergic to penicillins
- Substitute with ciprofloxacin, azithromycin or clindamycin
- Can be used in combination with metronidazole
Azithromycin
* Bacteriostatic for?
* Effective against most?
* tissue concentration?
* Better compliance because ?
* Can be used in combination with?
- Bacteriostatic for most pathogens
- Effective against most anaerobes, gram-positive and negative bacteria.
- Good tissue concentration
- Better compliance because it is given qd
- Can be used in combination with metronidazole
Metronidazole
* Attain effective antibacterial concentration in?
* Particularly effective against?
* Adverse reaction when taken with?
* Do not combine it with?
- Attain effective antibacterial concentration in
gingival tissue and GCF - Particularly effective against anaerobic bacteria and spirochetes
- Bactericidal
- Adverse reaction (nausea, vomiting, cramping) when taken with alcohol.
- Do not combine it with warfarin, lithium, phenytoin,
cyclosporin
Antibiotic Regiment In phase I therapy
which abx? dosages? time frame?
Metronidazole + Amoxicillin combination
* van Winkelhoff cocktail: 375mg Amox+250mg Metro. TID 7 days
* 500 mg of Amox. and 500 mg of Metro. TID
* 250 mg of Amoxicillin and 250 mg of Metronidazole TID or QID
* 7 days or 14 days of administration
Antibiotic Regiment
In acute periodontal abscess cases
Host Modulation
- Aims to reduce tissue destruction by modifying
the host response
Host Modulation goals
* Reduce excessive amounts or activity of?
* Increase?
* Modulate activty of what cells?
* No impact on?
* Promote ?
- Reduce excessive amounts or activity of lytic enzymes/cytokines/inflammatory mediators
- Increase anti-inflammatory mediator amounts or activity
- Modulate osteoblast and osteoclast activity
- No impact on physiologic cell function; contribute to sustained control of “harmful” bugs
- Promote connective tissue repair or regeneration and produce clinically significant results
NSAIDS
* Target?
* Selective?
* Indomethacin, flurbiprofen and naproxen long term daily use (up to 3 years) can lead to?
* Serious side effects ?
used as adjunct?
- Target prostaglandins and inflammation
- Selective COX-1 vs COX-2 inhibitors
- Indomethacin, flurbiprofen and naproxen long term daily use (up to 3 years) can lead to slower disease
progression - Serious side effects such as GI irritation, liver and renal damage/ dysfunction
Not used as adjuncts in periodontal therapy
Bisphosphonates
* Disrupt?
* Can improve?
* Serious side effects with?
approved application in periodontal therapy?
- Disrupt osteoclast activity
- Can improve alveolar bone density but the role in disease progression in humans is unclear
- Serious side effects with IV agents (osteonecrosis of the jaw after oral surgery
No approved application in periodontal therapy
Tetracyclines and conn tissue
- Tetracyclines (TCs) inhibit connective tissue breakdown
TCs inhibition of conn tissue breakdown
- Mediated by extracellular mechanisms
- Direct inhibition of active MMPs
- Inhibition of oxidative activation of Pro-MMPs
- Inhibition of MMPs indirectly decreases serine proteinase activity
- Mediated by cellular regulation
- TCs decreases cytokines, iNOS, PLA, prostaglandin synthase
- Effects on protein kinases (MAPA)**
- Mediated by pro-anabolic effects
- TCs increases collagen production
- TCs increases osteoblast activity and bone formation
Subantimicrobial Dose
Doxycycline (SDD
- Among tetracyclines, Doxycycline has the best anticollagenolytic activity and better GI absorption
- Currently the only FDA approved host modifier as adjunct to SRP
SDD administration
* ? mg doxycycline, time frame?
* Adjunct to?
* SDD doesn’t result in?
* Contraindicated in?
* May reduce efficacy of?
- 20 mg doxycycline twice daily or 40mg once daily, for 6-9 months
- Adjunct to thorough and high-standard SRP
- SDD doesn’t result in antibacterial effects/development of resistant strains/multiantibiotic resistance
- Contraindicated in pregnancy or children for the risk of permanent teeth discoloration
- May reduce efficacy of contraceptives
SDD
* name/mech?
* FDA approved?
* DO NOT USE AS?
* Clinical significance?
- Periostat (CollaGenex Pharmaceuticals) is a
host-modulating agent. It inhibits host collagen-
degrading enzymes - FDA approved host modifier as adjunct to SRP
- DO NOT USE AS STAND-ALONE THERAPY
- Clinical significance? = 0.2-0.4mm difference in attachment gai
Antibiotic Prophylaxis
Heart conditions and Prosthetic joints if MD says so
Apply only to dental procedures requiring manipulation of the gingival tissue or the periapical region of teeth, or perforation of the oral mucosa.
heart conditons for Abx prophylaxis
Only patients at the highest risk of infective endocarditis
porsthetic joints and Abx prophylaxis
- For patients with a history of complications associated with their joint replacement who are undergoing dental procedures including gingival manipulation or mucosal
incision, antibiotic prophylaxis should only be considered after consultation with the
patient and orthopedic surgeon.
Prophylactic Regimens
Prophylactic Regimens:
Single dose 30-60 min before procedure
Amoxicillin (Amoxil®) of 2 g
Azithromycin (Zithromax®) of 500 mg
Clarithromycin (Biaxin®) of 500 mg
clindamyacin prophylaxis?
Clindamycin is no loner recommended for dental
procedure antibiotic prophylaxis due to more frequent
and serious adverse effects associated with
clindamycin compared to other prophylactic options,
including C. difficile infections.
Other Considerations of prophylaxis?
- grafting?
- implants?
- Consider 1 week of antibiotic use following bone
and soft tissue grafting - Antibiotic prophylaxis before implant placemen
