Prevalence of Subgingival Aggregatibacter actinomycetemcomitans and Periodontal findings in Cohort of Western Australians Diagnosed with Periodontitis: A Descriptive Cross-Sectional Study
Authors: Khzam Nabil , Kujan Omar , Haubek Dorte , Arslan Aysen , Johansson Anders , Oscarsson Jan , Razooqi Zeinab , Miranda Leticia Algarves 
Published: February 2024

Aim
To investigate the presence of Aggregatibacter actinomycetemcomitans in subgingival plaque samples isolated from patients with periodontitis, and to assess potential indicators of the risk of severe form(s) of periodontitis.
Materials and Methods
A descriptive cross-sectional study of 156 consecutive patients with periodontitis, aged between 26 and 86 years old, were recruited to two private periodontal practices in Western Australia, between June and November 2022. After collection of the patient’s biodata, periodontal, radiographic and photogenic examination, subgingival plaque samples were collected from shallow and deep periodontal pockets of the participants. Identification of A. actinomycetemcomitans was performed using quantitative Polymerase Chain Reaction utilising species-specific primers. A descriptive analysis, chi-square test, and binary logistic regression statistical evaluation were performed.
Results
The prevalence of A. actinomycetemcomitans in this population of 156 participants was 16% (25 patients). Using the 2018 Classification of Periodontal and Peri-implant Diseases and Conditions, the prevalence of stage-III periodontitis was 75.6% and more prevalent in older men, while the prevalence of stage-IV periodontitis was 22.4% and more prevalent in younger women. The most prevalent extension of periodontitis was the generalized form with 83.3%. The most common periodontitis grade was B (73.1%). We observed a significant relation of the risk of severe periodontitis (stage-IV) with poor oral hygiene (X2 = 10.15, p = 0.006), and attendance to dental appointments (X2 = 14.78, p = < 0.001 - B = 1.40, OR = 4.079; 95% CI 1.00-16.55). Using binary logistic regression analysis, we revealed a relationship between the advanced form of periodontitis and familial history of periodontitis (B= -0.79, OR = 0.45; 95% CI 0.21–0.93).
Conclusions
Twenty-five individuals in a sample of 156, were positive for A. actinomycetemcomitans. Poor oral hygiene, family history of periodontitis, and irregular attendance to dental apportionments were identified as potential risk factors for severe periodontitis in this investigated sample of Western Australians.
Clinical Relevance: A. actinomycetemcomitans
is a key pathogen implicated in the pathogenesis of periodontitis. The presence of this pathogen was not documented before in a cohort of Western Australians. We have noted a relatively low presence of A. actinomycetemcomitans in this cohort of Western Australians, which can be compared to some studies in the European population. We also identified some risk factors that can contribute to the severe form of periodontitis in this population. Describing the distribution of A. actinomycetemcomitans and their association with various clinical parameters aid in our understanding of the natural history of periodontal disease in the population of Western Australians.