Periodontitis is caused by a set of inflammatory disorders characterized by destruction of supporting tissues of the teeth, pocket formation and alveolar bone loss. Current understanding of periodontitis suggests that subgingival biofilm microorganism is the primary cause of periodontitis which leads major periodontal destruction stimulated by host inflammatory reaction. Previous studies have shown that omega-3 fatty acids, aspirin and aloe-emodin exhibited the potential anti-inflammation effects. Thus these studies were aim to evaluate the effects of omega-3 fatty acids plus aspirin and aloe-emodin on ligature-induced periodontitis in rats. Omega-3 fatty acids plus aspirin inhibited the LPS-stimulated cyclooxygenase (COX-2), inducible nitric oxide synthase (iNOS) and RANKL-mediated osteoclast-related genes including receptor activator of nuclear factor κ B (RANK), tartrate-resistant acid phosphatase (TRAP), metalloproteinases 9 (MMP-9), MMP-2 and Cathepsin-K. The administration of omega-3 fatty acids and aspirin significantly inhibited tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in serum of rats. Furthermore, omega-3 fatty acids plus aspirin promoted alveolar bone increase in the periodontitis model.Although mice and humans do not synthesize chitin and its synthase, they do express two active chitinases, chitotriosidase (Chit1) and acidic mammalian chitinase (AMCase). AMCase has attracted substantial attention due to its fluctuational expression under certain pathological conditions such as asthma, allergic inflammation, ocular allergy, dry eye syndrome and gastric cancer. In this study, RANKL-induced osteoclast formation and differentiation from RAW264.7 cells and bone marrow-derived macrophages (BMMs) were significantly inhibited by reduction of AMCase under Aloe-emodin treatment. Aloe-emodin also decreased the protein expression of AMCase in saliva and periodontal tissue. Histomorphometric analysis demonstrated aloe-emodin promoted alveolar bone increase in the periodontitis model. Moreover, the level of AMCase between healthy subjects and periodontitis patients were also compared. Western blot and ELISA assay showed that AMCase in periodontal tissues expressed higher level in periodontitis patients than healthy subjects.Taken together, these studies showed that omega-3 fatty acids plus aspirin and aloe-emodin could decrease alveolar bone loss, while simultaneously increasing the protection against periodontal inflammation. AMCase may play a potential biomarker for the diagnosis or screening of periodontitis patients.