Novel Method to Target Apical Periodontitis Worsened by Inflammatory Bowel Disease

Area of Science:

• Oral biology
• Immunology
• Gastroenterology

Background:

• Patients with inflammatory bowel disease (IBD) exhibit a higher prevalence of apical periodontitis (AP).
• The mechanisms driving accelerated jawbone destruction in patients with co-occurring IBD and AP are not well understood.
• IBD-associated systemic inflammation may impact local immune responses in the jawbone.

Purpose of the Study:

• To investigate the exacerbation of apical periodontitis (AP) and associated alveolar bone destruction in a model of colitis.
• To elucidate the role of inflammation and neutrophils in the combined condition.
• To evaluate the efficacy of targeted immunosuppressant delivery for treating exacerbated AP in the context of colitis.

Main Methods:

• Establishment of a colitis and apical periodontitis (AP) co-morbidity mouse model.
• Gene expression analysis to identify inflammatory and neutrophil-related pathways.
• Histological examination to assess local neutrophil infiltration in alveolar bone.
• Application of a laser-induced cavitation system for localized delivery of tacrolimus.

Main Results:

• The colitis+AP model demonstrated significantly exacerbated alveolar bone destruction compared to the AP-only model.
• Upregulation of inflammation and neutrophil-associated genes was observed in the colitis+AP model.
• Colitis induced increased neutrophil infiltration in alveolar bone, further amplified by root canal infection.
• Targeted local delivery of tacrolimus via laser-induced cavitation effectively suppressed alveolar bone loss in the colitis+AP model.

Conclusions:

• Systemic inflammation from IBD impairs local neutrophil function, leading to increased bone destruction and treatment-resistant AP.
• The interplay between IBD and AP involves heightened inflammatory responses and neutrophil activity.
• Laser-activated local administration of tacrolimus presents a promising therapeutic strategy for managing severe AP associated with IBD.