Dental Guidance

This guidance is based on the Scottish Dental Clinical Effectiveness Programme guide to drug prescribing in dentistry.

To provide evidence for the guidance a literature review using Medline and Cochrane has been conducted, by Dr Joanne Hooker, up to October 2011 searching for Gingivitis; Antibiotics & dental abscess; Mucosal ulceration; Metronidazole; Oral Inflammation; Microbial flora & oral cavity; Oral hygiene; Oral microbial pathogens; Acute necrotising ulcerative gingivitis; Ludwig’s angina; Dentoalveolar abscess; Mucositis; Odontogenic infection; Antimicrobials & dentistry; Pericoronitis; Periodontal disease; Mouthwash/mouthrinse; Periodontitis; Chlorhexidine; Anti-plaque/anti-gingivival; Hydrogen peroxide; Antimicrobial susceptibility; Saline solution. The rationale was written by Dr Joanne Hooker under the guidance of Dr Cliodna McNulty and reviewed by stakeholders. Where only expert opinion was available, the guidance was based on the literature on the main pathogens and their antimicrobial susceptibility profiles in the UK.

Dosage of antimicrobials recommended in this guidance:

The Scottish Dental Clinical Effectiveness Programme 2011 recommends doses of 250mg amoxicillin or 200mg metronidazole when antimicrobials are appropriate. We recommend a higher dose of 500mg amoxicillin and 400mg metronidazole. The rationale for this is when antimicrobials are considered appropriate, it is important to have sufficient concentrations at the site of infection. For β-lactams such as amoxicillin this is time-dependent (i.e. the time period above the MIC) and 500mg TDS amoxicillin is more likely to attain this. For metronidazole, the killing effect is dose-dependent and the greater the concentrations above the MIC the better. AUC/MIC >70 is only attainable against Bacteroides fragilis with a 400mg dose.

There are few randomised controlled trials or systematic reviews looking at outcomes of dental abscess with and without antibiotics. The guidance is mainly based on expert opinion and laboratory susceptibility data of the organisms usually found in the dental conditions described.

Matthews DC, Sutherland S, Basrani B. Emergency management of acute apical abscesses in the permanent dentition: a systematic review of the literature. J Can Dent Assoc 2003;69:660. In the management of localized acute apical abscess in the permanent dentition, the abscess should be drained through a pulpectomy or incision and drainage. This analysis indicated that antibiotics are of no additional benefit. In the event of systemic complications (e.g., fever, lymphadenopathy or cellulitis), or for an immunocompromised patient, antibiotics may be prescribed in addition to drainage of the tooth.

Dahlen G. Microbiology and treatment of dental abscesses and periodontal-endodontic lesions. Peridontol 2000 2002;28:206-239. This review recommends that definitive surgical treatment to drain the abscess (through incision, extraction or removal of necrotic pulp) by a dentist is the primary management of a dentoalveolar abscess. The use of antibiotic treatment is required only in cases where there is evidence of systemic illness or in the severely immunocompromised and is aimed at limiting spread and preventing serious complications.

Ellison SJ. The role of phenoxymethylpenicillin, amoxicillin, metronidazole and clindamycin in the management of acute dentoalveolar abscesses – a review. Br Dent J 2009;206:247-62. This British literature review and literature search of over 5,000 references worldwide using Embase, Medline and Cochrane (search criteria antibiotics and dental) concluded that there is little evidence-based antibiotic prescribing in the case of dental infections and to help control increasing antimicrobial resistance it is important to only prescribe antimicrobials if indicated. Antimicrobials should be prescribed if systemic sign of acute dental abscess include: pyrexia, trismus, lymphadenopathy, gross facial or ocular oedema, dysphagia, tachycardia or rigours.

Kuriyama T, Absi EG, Williams DW, Lewis MAO. An outcome audit of the treatment of acute dentoalveolar infection: impact of penicillin resistance. Br Dent J 2005;198:759-63 (UK). 112 patients with dentoalveolar infection underwent incisional or dental pulp chamber drainage and were assigned to one of six different antibiotic regimes. No significant difference in outcome was found with any regime, and the presence of penicillin-resistant strains did not influence the outcome where surgical management was already established (Student-T analysis for the comparison of clinical improvement scores) questioning the indication for antibiotics at all. However this study did not look at cases where antibiotics were not prescribed where adequate drainage had been achieved, and reinforced that it would be unethical to undertake such a study where systemic signs of infection were evident.

Preshaw PM. Antibiotics in the treatment of periodontitis. Dental Update 2004;31:448-56. Informal expert opinion. Scientific research demonstrating the impervious nature of dental biofilms to antibiotics (microorganisms can survive concentrations 500-1000 times greater than required for systemic delivery, Walker 2002) illustrated the rationale for definitive surgical management prior to considering this as an adjunct and Preshaw reinforces that in most cases systemic treatment is not required.

Robertson D, Smith AJ. The microbiology of the acute dental abscess. Med Microbiol. 2009;58:155-62. Informal expert opinion, literature review. Despite few well controlled trials, the literature available supports the use of urgent surgical management of the dental abscess in combination with antimicrobial agents where there is evidence of cellulitis or sepsis.

Scottish Dental Clinical Effectiveness Programme, 2011. Formal expert opinion. The Scottish guidance recommends a dosage regimen of 250mg amoxicillin TDS. Expert opinion at Public Health England and Department of Health Advisory Group on Antimicrobial Resistance & Healthcare Associated Infection is to increase concentrations at the site of infection above the minimum inhibitory concentration needed to eradicate the infecting bacteria, especially for more resistant Bacteroides spp. In severe infection double the dose of amoxicillin (from 500mg – 1g TDS) or in the case of phenoxymethylpenicillin (500mg – 1g QDS).

Eick S, Pfister W, Straube E. Antimicrobial susceptibility of anaerobic and capnophilic bacteria isolated from odontogenic abscesses and rapidly progressive periodontitis. Int J Antimicrob Agents 1999;12:41-6. This German study looking at the susceptibility of microbiological samples taken from 140 patients with dentoalveolar disease (peridontitis or odontogenic abscess) showed that the isolates consisted mainly of gram negative anaerobes which were highly susceptible to metronidazole and clindamycin. 6% of the periodontal isolates (plaque) and 22% of the abscess isolates (pus) were resistant
to penicillin.

Kuriyama T, Absi EG, Williams DW, Lewis MAO. An outcome audit of the treatment of acute dentoalveolar infection: impact of penicillin resistance. Br Dent J 2005;198:759-63 (UK). A clinical study looking at the antimicrobial susceptibility of 800 anaerobic isolates from dentoalveolar infections in Japan. The study concluded that amoxicillin is still advocated as a first-line agent as it exhibits a high level of activity against the majority of organisms responsible for dentoalveolar infections. However, resistance to amoxicillin was seen in β-lactamase- producing Prevotella species and therefore in more severe infections these organisms need to be covered. Amoxicillin/clavulanate, clindamycin and metronidazole have excellent activity against Prevotella species and the other anaerobes found in dentoalveolar infections. Susceptibility and resistance profiles of cephalosporins were found to be similar to amoxicillin, and therefore have no advantage over amoxicillin and are associated with greater side effects and the development of resistance.

Kulik EM, Lenkeit K, Chenaux S, Meyer J. Antimicrobial susceptibility of periodontopathogenic bacteria. J Antimicrob Chemother 2008;61:1087-1091. A laboratory-based microbiological study in Switzerland (where antibiotic use is among the lowest in Europe) looking at the resistance profiles of three predominant periodontopathogenic bacteria isolated from dental abscesses over a fourteen year period to 2005, concluded that there was limited antibiotic resistance to phenoxymethylpenicillin, amoxicillin/clavulanic acid, clindamycin, tetracycline and metronidazole. The study reiterated the polymicrobial nature of periodontal infections and that while resistance may well be present amongst commensal flora, resistance to individual species implicated in dental abscesses is not currently an issue.

Martin MV, Longman LP, Hill JB, Hardy P. Acute dentoalveolar infections: an investigation of the duration of antibiotic therapy. British Dental Journal, 1997;183;135-37. This British study looked at 759 patients with acute dental abscess (and associated systemic features), managed with either abscess drainage or tooth extraction in combination with amoxicillin, clindamycin or erythromycin. The outcome measured the resolution of systemic symptoms (swelling and temperature) after 2-3 days and then at 10days and found 98.6% of cases had resolution of symptoms at the first review (where upon antibiotics were discontinued), furthermore these patients did not need an additional course of antibiotics at a later stage. This study shows that if drainage has been established antibiotics may not be needed beyond 2-3 days. Clinical review may be difficult so our guidance recommends 5 days duration.

Scottish Dental Clinical Effectiveness Programme 2011. Formal expert opinion. Avoid clindamycin, clarithromycin, cephalosporins and amoxicillin/clavulanate as first line agents (no advantage over amoxicillin, phenoxymethylpenicillin, metronidazole or erythromycin). Clindamycin and amoxicillin/clavulanate can be used as second-line agents where infection has not resolved however there is a risk of Clostridium difficile. An alternative diagnosis should be sought if the abscess is not resolving with local measures in combination with first-line antimicrobials.

The POCAST project is funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Imperial College London and by the Imperial College Healthcare Charity (Grant Ref No:7006/P36U).