Antibiotic stewardship has changed the way dentistry prescribes. Across almost every scenario, source control — debridement, drainage, extraction, aseptic surgical technique — outperforms a prescription, and prophylaxis is now recommended far less often than a decade ago. The cards below summarise where antibiotics still earn their place, and where they no longer do.
Scenarios & prescribing protocols
For the vast majority of patients, excellent oral hygiene — not antibiotics — is the key defence against distant-site infection.
Infective endocarditis (IE)
Selective use
- Reasonable only for the highest-risk patients: prosthetic valves or material, prior IE, selected congenital heart disease, cardiac transplant valvulopathy.
- Only before procedures involving gingival manipulation, periapical manipulation or oral mucosal perforation.
- Not for mitral valve prolapse, rheumatic heart disease, most congenital defects, bicuspid or calcific valves.
Cardiac devices, vascular grafts, joints and hardware
Not recommended
- Pacemakers, ICDs, coronary and peripheral stents, vascular and haemodialysis grafts: no convincing evidence dental bacteraemia causes device infection.
- Prosthetic joints: not routine. Consider only after discussion with the orthopaedic surgeon for higher-risk patients (prior joint infection, immunocompromise, poorly controlled diabetes, extensive invasive procedure).
- Pins, plates and screws outside a synovial joint: no role for prophylaxis (Grade D, Level 4).
IE regimen — single dose, 30–60 minutes pre-procedure
Adult dose (child 50 mg/kg, max adult dose)
- Oral: amoxicillin 2 g.
- Penicillin allergy, oral: cephalexin 2 g (or azithromycin, clarithromycin or doxycycline).
- Unable to take oral: ampicillin 2 g IM/IV (or cefazolin / ceftriaxone).
- Penicillin allergy and unable to take oral: cefazolin or ceftriaxone 1 g IM/IV.
- Avoid cephalosporins after anaphylaxis, angioedema or urticaria to penicillin. Clindamycin is no longer recommended for dental prophylaxis.
Clinical pearl Before reaching for prophylaxis, ask whether the patient truly falls into a highest-risk category. For nearly everyone else, daily oral hygiene protects better than a pre-procedure pill.
Remove the source first: access, drainage or extraction. Then decide whether systemic cover adds anything.
Systemic antibiotics not indicated
Grade A (C where noted)
- Irreversible pulpitis.
- Symptomatic apical periodontitis or localised acute apical abscess with no systemic signs.
- Preventing endodontic flare-ups after treatment.
- Promoting periapical healing of apical pathosis (C).
- Routine endodontic microsurgery in healthy adults.
Antibiotics as an adjunct
Consider
- Systemic signs and symptoms — malaise, lymphadenopathy, pyrexia.
- Spreading odontogenic infection: cellulitis, trismus, dysphagia.
- Immunocompromised patient with acute apical abscess or odontogenic infection.
- Empirical choice: a penicillin combined with metronidazole; reassess at 48–72 hours and stop once controlled.
Topical & intracanal agents
Limited role
- Antibiotic/corticosteroid pastes (Ledermix®, DoxyPaste, Odontopaste®) may control post-operative pain between appointments, largely via the corticosteroid.
- Triple antibiotic paste (ciprofloxacin + metronidazole + minocycline) is used in regenerative endodontics of necrotic immature teeth; minocycline discolours, so consider double-antibiotic or modified pastes.
- The European Society of Endodontology does not recommend routine topical antibiotics in conventional endodontics.
Clinical pearl Antibiotics should always follow source control, never replace it.
Routine adjunctive use is not recommended for the general periodontitis population (Grade A).
Who may benefit
Selective use (B)
- Age under 56 with probing pocket depth ≥5 mm in ≥35% of sites, alongside non-surgical therapy.
- Age under 36, or a history of aggressive / Stage III periodontitis, with subgingival plaque removal.
- Age 56 and above: systemic antibiotics should not be given a priori.
- Never prescribe on bleeding-on-probing incidence alone (A).
Timing & technique
Good practice point
- Antibiotic intake should start on the day debridement is completed.
- Complete debridement within a short window — preferably under one week — and to an adequate standard.
Surgery and local delivery
Case-by-case
- No routine benefit for preventing post-surgical infection; prevalence is already low.
- Consider in immunocompromising conditions (e.g. diabetes) or extensive surgery such as large hard-tissue augmentation (B).
- Locally delivered fibres, gels, chips or microspheres show probing-depth reduction and attachment gain at 6–9 months, but effect varies widely by formulation.
Clinical pearl Match systemic antibiotic use to age, disease severity and pocket depth — not to bleeding scores.
Amoxicillin 2 g one hour pre-operatively has shown some benefit in the literature; routine peri- and post-operative courses have not.
Placement and prosthetic phase
Not indicated (A)
- Prophylaxis is not indicated in straightforward implant surgery in healthy patients.
- Pre- and post-operative antibiotics are not indicated for stage 2 surgery.
- No evidence of benefit during the prosthetic phase.
When to consider
Selective use (D)
- Immunocompromised patients showing signs of systemic infection.
- Specific complex cases involving bone grafting or sinus lift; evidence for sinus elevation is insufficient either way.
Peri-implantitis
Mechanical & surgical first (B)
- No controlled studies demonstrate efficacy of adjunctive systemic antibiotics.
- Locally delivered agents may improve bleeding on probing and probing depth versus debridement alone, but formulations differ greatly.
Clinical pearl Case selection and asepsis matter far more than a prescription; reserve antibiotics for complex grafting or genuine systemic infection.
Amoxicillin is first-line for most dentoalveolar infections and surgery; alternatives include amoxicillin-clavulanate or metronidazole.
Extractions & dry socket
Selective / not indicated (A)
- Routine extraction of non-infected teeth: not indicated.
- Impacted third molars: prophylaxis reduces infection, dry socket and pain but increases mild adverse effects; no benefit for fever, swelling or trismus.
- Alveolar osteitis: systemic antibiotics not indicated for prevention or treatment; 0.12% chlorhexidine pre-operative rinse is the evidence-supported option.
MRONJ, ORN and established infection
Source control first
- MRONJ prevention: bone-penetrating prophylaxis may be considered pre-operatively in high-risk patients (D); for established MRONJ favour surgery once medical therapy has failed.
- Irradiated patients: pre/post-operative cover may be considered for ORN risk, effectiveness uncertain (D).
- Odontogenic infections: remove the source or drain first (A), then penicillin + metronidazole.
- Non-odontogenic, skin-sourced infections: cloxacillin, pending culture.
Trauma & orthognathic surgery
Procedure-dependent
- Mandible / dentoalveolar maxilla fractures: perioperative prophylaxis recommended (B), short course only — no added benefit beyond 24 hours (A).
- No transoral approach or minimally invasive: prophylaxis not needed.
- Oral mucosal incision: 24-hour prophylaxis reduces surgical site infection (A); in orthognathic surgery a 5-day course may add benefit, weighed against risk.
Clinical pearl Ask first whether the source has been removed or drained. If not, operative treatment — not a prescription — is the next step.
Default to the current IADT guideline rather than routine prescribing, and document tetanus status and soft-tissue involvement.
Luxation & fractures
Not routine
- IADT does not recommend antibiotics for luxation or fracture injuries in permanent or primary teeth unless soft-tissue injury or a medical condition warrants cover.
- Limited effect on pulpal or periodontal healing for root fractures and intrusive luxation.
Avulsion & replantation
Recommended
- Systemic antibiotics are recommended for replantation of an avulsed permanent tooth.
- Doxycycline is the usual choice, avoided under age 12 due to discolouration risk.
- Topical antibiotic soaking of the avulsed tooth is no longer recommended.
Intracanal medicament & autotransplantation
Consider / inconclusive
- Antibiotic-corticosteroid pastes (e.g. Ledermix®) may reduce infection-related root resorption, based mainly on animal studies; place immediately and retain at least 6 weeks per IADT.
- Autotransplantation: antibiotics are commonly prescribed empirically with wide practice variation; evidence of benefit is mixed.
Clinical pearl In trauma, the guideline — not habit — should decide whether a prescription is written.
Match the antibiotic to the organism and the allergy history: amoxicillin first.
First-line and adjuncts
Grade A/B
- Amoxicillin: empirical choice for odontogenic infections and endocarditis prophylaxis in non-allergic children (A).
- Amoxicillin-clavulanate: where both staphylococcal and streptococcal infection are present, e.g. juvenile recurrent parotitis, submandibular sialadenitis (B); may cause GI disturbance.
- Metronidazole: added to amoxicillin when anaerobic involvement is present (A).
Penicillin allergy
Alternatives
- Cephalosporins such as cephalexin (B); avoid after anaphylaxis, angioedema or urticaria to penicillins.
- Azithromycin is acceptable if allergic to both penicillins and cephalosporins (A); use macrolides with caution for cardiotoxicity risk.
Use with caution
Caution
- Clindamycin should be avoided — frequent, severe GI reactions; no longer used for endocarditis prophylaxis (A).
- Doxycycline: prescribe with caution for discolouration risk (D); short courses under 21 days in children under 8 have not been linked to staining and are useful in avulsion management.
Clinical pearl Always pair antibiotics with definitive treatment of the infection source, never as a substitute for it.
Ask two questions before prescribing: what is this patient's renal function, and what else are they taking?
Dosing
GPP / D
- No specific modification is needed for the healthy geriatric patient (GPP).
- Dose reduction is advisable where renal disease is diagnosed (D).
- Renal excretion of penicillins and cephalosporins declines with age; glomerular filtration falls around 30% versus younger adults.
Pharmacokinetic changes
Awareness
- Distribution: less body water and lean mass, so higher plasma concentration for a given dose.
- Metabolism and elimination: reduced hepatic clearance and glomerular filtration risk drug accumulation.
Key interactions
Review the full medication list
- Amoxicillin + allopurinol: rash.
- Fluoroquinolones + antacids (Al/Mg/Fe/Zn): reduced absorption.
- Metronidazole + warfarin or alcohol: increased warfarin effect; disulfiram-like reaction.
- Clarithromycin + statins, cyclosporine, digoxin, warfarin: increased effect of the interacting drug.
Clinical pearl A brief medication review prevents most antibiotic-related harm in older patients.
“Immunocompromised” is not a prescription in itself. Identify the specific condition, its severity and the treating specialist's input.
Diabetes & HIV
Not routine (C/D)
- No evidence of increased post-operative infection risk in well-controlled diabetics (C); prophylaxis only where a healthy patient would also warrant it.
- Poorly controlled diabetics: refer for glycaemic optimisation before invasive treatment.
- HIV: do not give pre-operative antibiotics based on HIV status or CD4 count alone (C); cover recommended for severe neutropenia below 500 cells/mm³ (D).
Cancer therapy
Case-by-case
- Treat infection sources before chemotherapy or radiotherapy begins where possible.
- Prophylaxis for invasive procedures if neutropenia is below 1000 cells/mm³, in liaison with the oncologist (D).
- During therapy, manage dental emergencies with the oncologist; after therapy prophylaxis is not routinely needed once counts normalise (GPP).
- Post stem-cell transplant: prophylaxis may be indicated up to 12 months — consult the transplant team (GPP).
Organ transplant
Consider (GPP)
- Pre-transplant: avoid erythromycin and clarithromycin, which raise cyclosporine levels.
- Post-transplant: prophylaxis is reasonable for invasive dental procedures, especially in the first 3 months or during rejection episodes.
Clinical pearl No blanket rule applies — liaise with the treating physician and emphasise prevention across all these groups.
Even standard doses can accumulate to harmful levels in advanced kidney disease.
Dosing in CKD
Good practice point
- Adjust antibiotic doses according to renal function (GPP).
- Check creatinine clearance (CrCl) or GFR before prescribing; refer to local drug references such as the National Drug Formulary for current adjustments.
Haemodialysis
Not routine (D)
- Antimicrobial prophylaxis is not routinely recommended for dental procedures.
- No convincing evidence that dental bacteraemia infects prosthetic vascular (haemodialysis) grafts.
- Reserve prophylaxis for patients with known cardiac risk factors for endocarditis.
Peritoneal dialysis
Consider — weak evidence
- Some sources recommend pre-procedural antibiotics before invasive dental work to prevent bacterial peritonitis, though supporting evidence is weak.
- No specific dental-society guidance exists — consult the renal physician if in doubt.
Clinical pearl A quick check of renal status prevents both under- and over-dosing; a call to the renal physician resolves most grey areas.
Compiled from the CDSS/AMS Practice Guidelines — Use of Antibiotics in Dentistry (Dec 2024). For clinical education only; always assess each patient individually and consult current local antimicrobial guidelines.