Effects of Initial Periodontal Therapy on Intraoral Bacterial Flora in Patients With Oral Contraceptive-Related Severe Gingivitis.

Gingivitis is a common inflammatory condition of the gingival tissues, influenced by microbial plaque and various systemic factors, including hormonal changes. Oral contraceptives containing estrogen and progestin are known to exacerbate gingival inflammation. We report the case of a 20-year-old Japanese woman who presented with gingival swelling and bleeding despite self-care, with a history of orthodontic treatment and oral contraceptive use. Clinical examination revealed probing pocket depths of ≥ 4 mm and bleeding on probing in more than half of the sites, a periodontal inflamed surface area (PISA) of 995.8 mm2, and a plaque control record of 78%. Bacterial analysis identified elevated levels of Prevotella intermedia, Prevotella melaninogenica, and Fusobacterium nucleatum. Initial periodontal therapy-consisting of scaling and root planing, supported with systemic and topical antibiotics-was provided, followed by gingivectomy at sites lacking adequate gingival attachment. Posttreatment evaluation demonstrated marked reductions in probing depth, bleeding on probing, and PISA (44.9 mm2), with plaque control improving to 31.3%. Microbiome analysis revealed a decrease in pathogenic anaerobes and an increase in beneficial aerobic bacteria. The patient's oral hygiene practices improved substantially through targeted education and self-care instruction, supporting the maintenance of periodontal health. This case highlights that initial periodontal therapy, combined with patient education and regular monitoring, can effectively reduce gingival inflammation and favorably modify the oral microbiome in oral contraceptive-related gingivitis. Awareness of the potential impact of oral contraceptives on periodontal health and implementation of individualized oral hygiene measures are essential for preventing disease progression in similar patients.