Comparative In Vitro Resistance of Human Periodontal Bacterial Pathogens to Tinidazole and Four Other Antibiotics

Thomas E Rams; Jacqueline D Sautter; Arie J van Winkelhoff

doi:10.3390/antibiotics9020068

Comparative In Vitro Resistance of Human Periodontal Bacterial Pathogens to Tinidazole and Four Other Antibiotics

Antibiotics (Basel). 2020 Feb 7;9(2):68. doi: 10.3390/antibiotics9020068.

Authors

Thomas E Rams^{1

2}, Jacqueline D Sautter¹, Arie J van Winkelhoff^{3

4}

Affiliations

¹ Department of Periodontology and Oral Implantology, Temple University School of Dentistry, Philadelphia, PA 19140, USA.
² Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, PA 19140, USA.
³ Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands.
⁴ Department of Periodontology, University of Groningen, University Medical Center Groningen, Center for Dentistry and Oral Hygiene, 9713 GZ Groningen, The Netherlands.

Abstract

The in vitro resistance of selected red/orange complex periodontal pathogens to tinidazole was compared with four other antibiotics. Subgingival biofilm samples from 88 adults with severe periodontitis were anaerobically incubated on enriched Brucella blood agar with and without supplementation with tinidazole (16 mg/L), metronidazole (16 mg/L), amoxicillin (8 mg/L), doxycycline (4 mg/L), or clindamycin (4 mg/L). Growth of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia/nigrescens, Parvimonas micra, Fusobacterium nucleatum, Streptococcus constellatus, or Campylobacter rectus on antibiotic-supplemented plates indicated their in vitro antibiotic resistance. Tinidazole inhibited all test species, except P. intermedia/nigrescens, P. micra, and S. constellatus in 3.8%, 10.2%, and 88.9% of species-positive patients, respectively. Significantly fewer patients yielded tinidazole-resistant test species, and had significantly lower subgingival proportions of tinidazole-resistant organisms, than patients with amoxicillin, doxycycline, or clindamycin-resistant species, but not those with metronidazole-resistant strains. Joint in vitro species resistance to tinidazole and amoxicillin, or metronidazole and amoxicillin, was rare. Tinidazole performed in vitro similar to metronidazole, and markedly better than amoxicillin, doxycycline, or clindamycin, against fresh clinical isolates of red/orange complex periodontal pathogens. As a result of its similar antimicrobial spectrum, and more convenient once-a-day oral dosing, tinidazole should be considered in place of metronidazole for systemic periodontitis drug therapy.

Keywords: amoxicillin; anti-infective agents; clindamycin; doxycycline; drug resistance; in vitro; metronidazole; periodontal pocket; periodontitis; tinidazole.