Physical irritants

Cold, heat, vibration and other direct physical trauma can all damage the pulp. As long as microbial challenge is not part of the pulpal irritation, the final outcome of physical irritation is either reversible pulpitis or local or total aseptic necrosis of the pulp. The pulp is clearly more tolerant to low than high temperatures. Insufficient cooling during cavity or crown preparation may cause hemostasis or bleeding in the pulp with crown discoloration as a result. Uncentered burs with high speed may also cause bleeding and even necrosis.