Amoxicillin in dentistry

Management of dentalinfections

Overview

• Common bacterial infections in dentistry

• Microbiology of infections

• Empiric Therapy Regimens

• Amoxicillin-clavulanate

• Related studies

Common types of bacterial infection in dentistry:

• Pulpitis

• Periapical periodontitis

• Periodontitis

• Pericoronitis

http://www.dentalcare.com/enUS/dentaleducation/continuingeducation/ce336/ce336.aspx?ModuleName=coursecontent&PartID=4&SectionID=-1

Contd..

• Dental caries

• Postsurgical

infections

• Gingivitis

Microbiology

Odontogenic infections are multimicrobial:

• Gram (+) cocci, aerobic and anaerobic:

– Streptococci and their anaerobic counterpart, peptostreptococci

– Staphylococci, and their anaerobic counterpart, peptococci

http://www.dentalcare.com/en-US/dental-education/continuing-education/ce336/ce336.aspx?ModuleName=coursecontent&PartID=4&SectionID=-1

• Gram (+) rods:

– Lactobacillus, diphtheroids,

• Gram (-) rods:

– Fusobacterium, Bacteroides, Eikenella, Psuedomonas

(occasional)

Pathophysiology

• Dental caries results when the demineralization which occurs when certain species of micobes start producing acid and can survive in it.

• Dental caries erode the protective layers of the tooth (ie, enamel, dentin) and allow bacteria to invade the pulp, producing a pulpitis.

http://emedicine.medscape.com/article/909373-overview#a5

Pathophysiology

• Pulpitis can progress to necrosis, with bacterial invasion of the alveolar bone, causing an abscess.

• A periapical abscess that originates in the dental pulp and is usually secondary to dental caries is the most common dental abscess in children.


Pathophysiology

• A periodontal abscess involves the supporting structures of the teeth (periodontal ligaments, alveolar bone).

• This is the most common dental abscess in adults, but may occur in children with impaction of a foreign body in the gingiva.

• Pericoronitis describes the infection of the gum flap (operculum) that overlies a partially erupted or impacted third molar.


Empiric Therapy options

First line of drugs

• Penicillin V / Penicillin G

• Amoxicillin-clavulanate

• Clindamycin

http://emedicine.medscape.com/article/2060395-overview#showall

Second Line drugs

• Metronidazole

• Moxifloxacin

• Erythromycin

• Cephalexin

Amoxicillin-clavulanate

• Amino penicillins

• First line of drug in the management of dental infections especially

in treating penicillinase-producing staphylococci or those involving

gram-negative bacteria.

• Amoxicillin acts by inhibiting the bacterial cell wall synthesis and

clavulanic acid acts by inhibiting the penicillinase enzyme which

deactivates amoxicillin – synergistic action

http://www.webmd.com/drugs/2/drug-1531/amoxicillin-oral

Spectrum of activity

Gram-Positive Bacteria

Staphylococcus aureus

Enterococcus faecalis

Staphylococcus epidermidis

Staphylococcus saprophyticus

Streptococcus pneumoniae

Streptococcus pyogenes

Viridans group Streptococcus

http://www.rxlist.com/augmentin-drug/clinical-pharmacology.htm


Gram-Negative Bacteria

Eikenellacorrodens

Proteus mirabilis

Enterobacter species

Escherichia coli

Haemophilus influenzae

Klebsiella species

Moraxella catarrhalis



Anaerobic Bacteria

Bacteroidesspecies including Bacteroides fragilis

Fusobacterium species

Peptostreptococcus species


Dosage

• Forms: Suspension, chewable tablet, tablet, capsule

• Usual oral dosage:

Children: >3 months and <40kg: 20-40mg/kg/day in divided doses 8th hourly

OR 25-45 mg/kg/day in divided doses every 12 hours

Dosage

Children: >40 kg and adults: 250-500 mg every 8 hours

OR 500-875 mg every 12 hours

Adults : > 40 kg: 250-500 mg q8h or 875 mg q12h for at least 7 days; maximum dose: 2g/day

Benefits over other 1st line drugs

• Available in various dosage formulations

• Covers both Gram positive and Gram negative bacteria including

anaerobic bacteria

• Broad spectrum of activity

• Well tolerated

• Good compliance

• Safer with fewer adverse effects

Related studies

• A comparative study on amoxicillin and clindamycin was carried as

a rationale for antibiotic prophylaxis against infective endocarditis

involving 160 patients.

They reported that oral amoxicillin given prior to dental extraction

produced a significant reduction in post-extraction bacteraemia.

Maharaj B, Coovadia Y, Vayej AC. A comparative study of amoxicillin, clindamycin and chlorhexidine in the prevention of post-extraction bacteraemia.CardiovascularJournal of Africa. 2012;23(9):491-494. doi:10.5830/CVJA-2012-049.

Related studies

• In a randomized, double blind study involving 123 participants it was

observed that , amoxicillin administered pre- or postoperatively

demonstrated greater efficacy than placebo in preventing

postoperative complications in patients undergoing third molar

surgery.

http://www.sciencedirect.com/science/article/pii/S0278239111000954

Related studies

• Another study evaluated amoxicillin concentration in the serum,

jaw cyst and jaw bone after single oral administration among

44patients who underwent enucleation of jaw cyst

Reported that amoxicillin attains higher levels in periodontal cysts

than in dentigerous cysts, and higher in maxillary bone than in

mandibular bone.

Akimoto Y, Kaneko K, Tamura T. Amoxicillin concentrations in serum, jaw cyst, and jawbone following a single oral administration. J Oral Maxillofac Surg. 1982 May;40(5):287-93.

Comparative Efficacies of Amoxicillin, Clindamycin, and Moxifloxacin in Prevention of Bacteremia following Dental Extractions (BDE)

Prevalence of bacteremia at the baseline and postextraction (30 s, 15 min, and 1 h after completion of the dental extractions) in the different study groups.

Conclusion: AMX continues to be the antibiotic of choice for the prevention of BDE in patients who are “at risk” of BE and who are not allergic to PEN. MXF is a safe prophylactic alternative when beta-lactams are contraindicated.

http://aac.asm.org/content/50/9/2996.full

Related studies

• In a randomised comparative study, of co-amoxiclav and penicillin V for

dentoalveolar infections

• After drainage all patients improved but co-amoxiclav treatment provided

significantly greater decrease in toothache during the second and third days

post drainage.

• This may explained by the eradication of the beta-lactamase producing

bacteria with co-amoxiclav that would not be eradicated by penicillin V.

Lewis MA, Carmichael F, MacFarlane TW, Milligan SG. A randomised trial of co-amoxiclav versus penicillin V in the treatment of acute dentoalveolar abscess. Br Dent J. 1993 Sep 11;175(5):169-74.

Related studies

• A comparitive study of amoxicillin and penicillin on Bacteraemia after

dental extraction demonstrated that

• Both penicillin V (2 g oral dose) and amoxycillin are effective in

reducing the incidence of bacteraemia following dental extraction.

• However, amoxycillin is preferable to penicillin V for the oral

prophylaxis of endocarditis as it can provide much higher serum

levels than penicillin V during the 6 to 8 hours following extraction.

Shanson DC, Cannon P, Wilks M. Amoxycillin compared with penicillin V for the prophylaxis of dental bacteraemia. J Antimicrob Chemother. 1978 Sep;4(5):431-6

Thank you

Health & Medicine

Amoxicillin in dentistry