in brief
The direct pulp cap, whilst predictable for the traumatically exposed pulp, has a questionable long term prognosis where a carious exposure is concerned
The activity of a deep carious lesion in dentine can be preferentially modified, by sealing in the dentine caries. This allows reparative pulp-dentine complex reactions to take place
When such lesions are re-entered after six months or more the risks of directly exposing the pulp are reduced