TNF and periodontitis: TNF-α, a major proinflammatory mediator, is crucial in periodontitis-mediated additional periodontal tissue loss and bone resorption, because it stimulates activation, proliferation, and differentiation of osteoclasts, which results in bone loss.2,13 Caspase activation orchestrates a localised chronic inflammatory response, and is necessary for TNF-α expression in periodontitis.21,26 Both healthy and periodontitis-affected saliva can be tested for caspase activation and TNF-α expression.