Local and Systemic Antimicrobial Therapy in Periodontics

Abstract

Context: This review aimed to update the current evidence on the efficacy of the adjunctive use of local and systemic antimicrobials in the treatment of periodontitis and to assess whether it might improve the clinical limitations and shortcomings of standard nonsurgical treatment in the management of periodontitis.

Evidence Acquisition: Relevant randomized clinical trials (RCT) with more than 3 months of follow-up, published from 2010 to 2012 for systemic antimicrobials and from 2008 to 2012 for local antimicrobials, were searched in Medline and critically analyzed. Scientific evidence evaluated in different systematic reviews and reviews presented at European and World Workshops were also included. Only adjunctive therapies were considered in the present review: articles comparing debridement alone or plus placebo, versus debridement plus systemic or local antimicrobials were included.

Evidence Synthesis: Adjunctive systemic antimicrobials have been evaluated both in aggressive and chronic periodontitis: in aggressive periodontitis, amoxicillin and metronidazole have been extensively studied, reporting clinical and microbiological benefits; in chronic periodontitis, different products are under scrutiny, such as azithromycin. The clinical efficacy of local antimicrobials, although extensively demonstrated, is still surrounded by a constant debate on the cost-effectiveness evaluation and on its adequate indications.

Conclusions: Despite the clinical efficacy of the adjunctive use of local and systemic antimicrobials, demonstrated in RCTs and in systematic reviews, there is a lack of evidence to support well-defined clinical protocols, including products and dosages.

Introduction

It is widely accepted that periodontal diseases are plaque-induced inflammatory conditions affecting the periodontium, and if left untreated, they may lead to destruction of the tooth-supporting apparatus and eventually to the tooth.¹ These conditions are caused by pathogenic bacterial species¹ that adhere to tooth surfaces organized in complex communities forming biofilms.² Among the more than 700 different bacterial species that have been identified in the oral microbiota, only a small group of 10 to 15 species has been identified as being significantly associated with the initiation and progression of periodontitis.3, 4 In spite of this microbial specificity, however, the standard treatment of periodontitis remains highly unspecific, mainly consisting of the mechanical debridement of the root surface. This nonspecific treatment approach has proven successful on a long-term basis for many patients,⁵ although a small, but relevant proportion of sites and patients may not respond adequately.⁶ Mechanical debridement is a highly demanding therapeutic procedure that presents some limitations, such as the inability to access deep, tortuous pockets and furcations; the limited effect over certain pathogens and oral niches; and the frequent occurrence of secondary effects (gingival recession, loss of tooth substance, dentin hypersensitivity, and so forth).7, 8 Because of these limitations, the adjunctive use of antimicrobials has been indicated to improve the clinical outcomes in certain patients and periodontal conditions.5, 9, 10

Adjunctive antimicrobials can be used either systemically¹¹ or locally. The local application has been indicated in patients with localized pockets or nonresponding and recurrent sites12, 13 because there are fewer adverse effects, less chance of developing bacterial resistance, and better compliance than with the use of systemic antimicrobials.14, 15 In these clinical situations, this local application may avoid the need for surgical therapy16, 17, 18 and, hence, there is a positive cost-benefit ratio.¹⁹ Over the years, however, the practical value of these locally applied antibiotics has been questioned, and most of the tested products have been withdrawn from the market for economic reasons or administrative obstacles.²⁰

The adjunctive benefits of systemic antimicrobials in the treatment of periodontitis have been reported in various systematic reviews presented at European21, 22 and North American Workshops.²³ The main conclusion has been that, although there are sufficient data to suggest that systemic antimicrobials might help in the treatment of periodontitis, there is not an optimum clinical protocol to be recommended.

This narrative review aims to analyze the current concepts on the use of local and systemic antimicrobials in the treatment of periodontitis and to update the current knowledge with the most recent scientific evidence.