Facial antibioma formation : A case report

Corresponding author: Muhammad S. Zafar. Department of Restorative Dental Sciences, College of Dentistry, Taibah University, P.O. Box 2898, Al Madinah Al Munawwarah, Saudi Arabia. Phone:(966) 507544691. E-mail: MZAFAR@taibahu.edu.sa Abstract: Odontogenic infections are associated with a variety of microorganisms. Antibiotics are commonly used for the management of various dental infections and have a proven role in decreasing morbidity and mortality caused by infectious diseases. The frequent and over usage of antibiotics has been associated with a number of consequences such as the selection of drug resistant strains, and the formation of antibiomas. Antibiomas are characterized by the formation of a localized pathology surrounded by thick fibrous tissues in response to long term antibiotics use. An established antibioma is characterized by a tough fibrous swelling accompanied by painful or painless swelling, intermittent fever and constitutional symptoms. In this article, we are reporting the case of a facial antibioma formed due to prolonged use of antibiotics prescribed for a residual periapical infection following endodontic treatment. In addition, the associati n of using antibiotics in this context is discussed.


INTRODUCTION.
Antibiotics are drugs used to restrict the growth of microorganisms. Antibiotics are commonly used for various dental infections and have a proven role in decreasing morbidity and mortality caused by infectious diseases. 1 Since most orofacial infections are mainly odontogenic in origin 2 the prescription of antibiotics has become an integral part of dental practice. In addition, odontogenic infections are associated with a variety of microorganisms and dentists do not routinely investigate which bacterial species is responsible for the infection, and hence prescribe broad spectrum antibiotics. 3 The frequent and over use of antibiotics has been associated with various issues such as the selection of resistant strains and the development of drug resistance in general. 3,4 Factors such as drug interactions with analgesics 3 or a tendency for selfmedicating 5,6 may also be contributing factors.
The management of odontogenic infections of pulpal origin including pulpitis and apical periodontitis, warrants operative interventions fillings, root canal therapy or extraction, as antibiotics are unlikely to resolve such infections. 7 Unfortunately, dentists commonly prescribe antibiotics for these conditions. 8,9,4 The prescription of antibiotics in dental clinical has increased from 6.7% to 11.3% in recent years. 10 Antibiotics prescription may lead to undesired effects ranging from systemic (gastrointestinal disturbances, selection of antibiotic resistance and fatal anaphylactic shock) 4 or local effects such as antibioma formation. The antibioma results from injudicious (prolonged or repeated) use of antibiotics to treat infections. For instance, using antibiotics without establishing proper abcess drainage leads to the formation of localized collection of sterile material surrounded by thick fibrous tissues. An established antibioma is characterized by a tough fibrous swelling accompanied by pain and intermittent fever and constitutional symptoms. 11 We are reporting a case of a facial antibioma formed due to prolonged use of antibiotics to treat a residual periapical infection following endodontic treatment. In addition, we dicuss the association of using antibiotics for a prolonged time in this context.

CASE REPORT.
A 26 year old female patient attended the SEGi Oral Health Centre with the chief complaint of a swelling in the right lower posterior region of the mandible present for two weeks. The patient was in general good health and reported no systemic illness. Intraoral examination revealed a swelling on the oral mucosa and a temporary restoration on the occlusal surface of a mandibular first molar (tooth 46). Extraoral examination revealed wellmarked swelling (2x2cm) at the lower border of the mandible near the tooth 46 area ( Figure 1).
The dental history revealed that tooth 46 was under for root canal treatment that had not been yet completed by the dentist. The patient reported a history of repeatedly and prolonged use of antibiotics including amoxicillin and metronidazole. Etoricoxib was used in conjunction with the antibiotics as a analsegic. The preoperative intra-oral periapical radiographs showed periapical lesion of tooth 46. The patient abandoned root canal treatment following the development of the swelling.
Considering the patient history and clinical presentation, various treatment options, their possible outcomes and related complications were explained to the patient. The agreed treatment plan comprised the surgical removal of tooth 46 and associated antibioma under local anesthesia followed by restoration of the lost tooth ( Figure 1). This case study was approved by the institutional ethical research board at SEGi University, Malaysia. Signed informed consent was obtained for the patient both for the treatment and for using the her data for the purpose of a research publication.

DISCUSSION.
This article reported a case of facial antibioma formed due to prolonged use of antibiotics. The patient was treated under local anesthesia by surgical removal of associated tooth and antibioma (a chronic abscess formed due to incomplete drainage of an infection and become sterile by antibiotics). Initially, in order to eradicate the infection, the patient was treated for root canal treatment. However, insufficient cleaning and shaping of the root canal lead to poor drainage and accumulation of biological material in the affected tooth.
The prolonged use of antibiotics to treat the residual infection and lack of proper postoperative follow-up led to the formation of the antibioma. Clinically, it was characterized by being painless, smooth, non-tender, and hard on palpation of the swelling. This clearly illustrated the importance of mechanical instrumentation (cleaning and shaping) and chemical disinfection of canals during root canal treatment. In addition, the root canal morphology varies among individuals 12,13 and this must be considered in order to avoid missing any canals. Inappropriate use of antibiotics involves unwanted systemic effects such as gastric, hematological, dermatological or neurological disorders. The most significant side effect is the appearance and selection of resistance to anti-microbial drugs. In order to ensure maximum efficacy and to minimize side effects (such as delaying the development of drug resistances), the rational and guidelines for using any antibiotic in dental clinics should be considered. 14 Although antibiotics have cured many diseases while benefiting a huge number of individuals, a sharp rise in the number of drug resistant strains of bacteria have ocurred in parallel due mostly to their inappropriate use.
For instance, the overuse of antibiotics has resulted in the selection of bacterial mutations that make those microorganisms no longer susceptible to these drugs. There are strains of Staphylococcus aureus resistant to a variety of antibiotics including vancomycin. The rate at which bacteria become resistant to drugs is quite alarming and has led to an increase in the morbidity and mortality of infectious diseases. 15 No uniform guidelines are available for indicating which antibiotics to use in such conditions in spite of high incidence of antibioma formation. It is reported by Bascones et al., 16 that as an adjunct to root canal therapy, the clinician should also encompass usage of antibiotics in cases of acute odontogenic infection of pulp origin. The authors are not convinced that using antibiotics in cases of chronic odontogenic conditions including chronic gingivitis, periodontitis or periodontal abscesses is warranted. In case of acute odontogenic infections of mixed nature, the drugs of choice are beta-lactam derivatives provided there are no allergies or intolerances. Nevertheless, the ambiguity about the specificity of a particular drug from the beta-lactam family still prevails.
Natural and semi synthetic penicillin (amoxicillin) is considered to be the first drug of choice by some clinicians 17 while others favor the usage of combination drugs (for example amoxicillin-clavulanate), because of the increasing number of bacterial strains resistant to beta lactams, as well as due to the pharmacological advantages of using a broad spectrum drug and its tolerance. 18 Alternatively, clindamycin has also been proposed as an alternative based on its properties such as quick absorption, lower rates of bacterial resistance, and higher concentrations delivered to the tissues. 19 In a dental setting the prescription of antibiotics is mostly associated with a concurrent nonsteroidal antiinflammatory drugs (NSAIDs) prescription. Antibiotics may have a range of possible interactions with other drug categories; for example, NSAID-mediated reduction of antibiotic bioavailability and its effects is well documented. 20,21 Although certain drug interactions (e.g. cephalosporins and ibuprofen, or tetracycline with naproxen or diclofenac) result in agonistic effects thus leading to enhanced bioavailability. 22,23 Hence, the decision whether the antibiotic should be prescribed or not for odontogenic reasons may not be straight forward and involves various parameters.
Dr. Thomas J. Pallasch adopted guidelines for antibiotic dosing; 24 which consider the drug's serum con-centration, bioavailability, duration of treatment (favoring shorter treatment periods), as well as dosing amounts and intervals considering the drug´s half-lives. In case of antibiotics for the treatment of orofacial infections, such as amoxicillin, the drug's half-life is short. Thus for orofacial infections, the recommended loading dose is double that of the maintenance dose. It is vital to consider the post antibiotic consequences of the drug and associated benefits of intermittent versus continuous dosing. For example for beta-lactam bactericidal activity, microorganisms need to be undergoing cellular division (as this drug mode of action is to interfere with cell wall development); hence, steady-state blood levels must be maintained as most of the bacteria divide at a variable times and pace. Therefore and amoxiclav. 25 Antibiotics should be considered as an adjunct to appropriate management of odontogenic infections. For example in case of the poor drainage of pus or the sealing of residual microorganisms, the patient may not obtain significant benefits from antibiotic treatment, leading to further complications such as antibioma formation. Public awareness programmes and educating health professional can be promising in controlling the unnecessary use of antibiotics hence avoiding relevant unwanted effects. 26

CONCLUSION.
The negligence regarding judicious antibiotic usage during the management of odontogenic infections may result in serious consequences. Therefore, the merits and disadvantages of prescribing antibiotics should be seriously considered. Further training and continuing education programs are required to educate health professionals as well as the general public about the proper usage of antibiotics and the associated side effects. Such measures are likely to reduce the unnecessary use of antibiotics.