Received Article-6-4-Prof. Hassan A.  Al-Shamahy


Husian Shogaa Al-Deen1 (MD, PhD)

Azhar Azher Mohammed Al-Ankoshy2  (MSc,PhD)

Mohammed Mohammed Ali Al-Najhi3 (MD, PhD)

Tagrid Ahmed Al-Kabsia4 (MD, PhD)

Khaled A AL-Haddad1 (MD, PhD)

Ameen Abdullah Yahya Al-Akwa1 (MD, PhD)

 Hassan Abdulwahab Al-Shamahy5  (MD, PhD)*

Mohammed A Al-labani1(MD, PhD)

 1-Orthodontics, Pedodontics and Prevention Department Faculty of Dentistry, Sana'a University, Yemen

2-Physiology Department, Jabir ibnHayyan Medical University, Faculty of Medicine/Iraq

3-Orthodontics, Pedodontics and Prevention Department Faculty of Dentistry, Genius University for Sciences and Technology, Dhamar city, Republic of Yemen.

4-Department of Maxillo-Facial, Faculty of Dentistry, Sana’a University, Republic of Yemen.

5-Departement of Basic Sciences, Faculty of Dentistry, Sana’a University, Republic of Yemen.

* Corresponding author: 

Prof. Hassan A.  Al-Shamahy

Faculty of Medicine and Heath Sciences

Sana'a University

P.O. Box 775 Sana'a, Yemen

Tel: +967-1-239551

Mobil: +967-770299847




Background: No information is available on the antimicrobial sensitivity pattern and guidelines for oral antibiotic therapy for Yemeni patients for those with localized aggressive periodontitis (LAP) due to Porphyromonas gingivalis, a condition that often requires complementary antibiotic treatment.

Aim: The primary objective of this study was to examine the antibiotic patterns and the potential relationship between P.gingivalis biofilm formation and the incidence of antibiotic resistance of clinical isolates on a group of antibiotics commonly used in oral/systemic therapy.

Materials and Methods: The study included 30 strains of P.gingivalis isolated from LAP patients. Microbial sampling, isolation, and identification of bacteria were performed using culture methods appropriate to anaerobic species and biofilm production was evaluated by the phenotypic method, that is, tissue culture methods (TCPM). Also; each isolate was tested against a combination of 12 antibiotics using the disc diffusion method. The test was performed and interpreted according to the CLSIFDA schedule.

Results: After isolated P.gingivalis were subjected to biofilm detection by TCP method, 7 (23.3%) showed high, 6 (20%) moderate, while 17 (56.7%) showed non/weak biofilm-forming ability. P.gingivalis biofilms showed a higher resistance rate than forming non/weak biofilms e.g amoxicillin (92.3% vs 64.7%, p = 0.08), azithromycin (58.8% vs 11.7, p =0.003), metronidazole (76.9% vs 29.4%, p = 0.08), 0.01) and clindamycin (84.6% vs 47.1, p = 0.03). Regarding all antibiotic sensitivity findings: cefotaxime, ceftriaxone and moxifloxacin showed excellent activity at 100% sensitivity, followed by amoxiclav (90%), tetracycline (83.3%), cefuroxime (80%), cefazolin (73.3%) and azithromycin (63.3%).In addition,  Bacterial strains showed poor sensitivity to clindamycin, doxycycline, metronidazole and amoxicillin.  

Conclusion: It was found that the drug-resistant factor in P.gingivalis isolates is associated with the formation of P.gingivalis biofilm. Even though the present results show a high sensitivity pattern for P. gingivalis strains, some resistance has been observed. Antibiotic resistance patterns can change over the years, making susceptibility testing essential and to promote careful selection of initial antibiotic therapy, as an adjuvant to endodontic therapy.

 Keywords:  antibiotic resistance, biofilm formation,  Porphyromonas gingivalis,  disc diffusion method.