A Possible Explanation for Tissue Separation Observed in Histological Sections after Regenerative Periodontal Therapy

Introduction: Tissue separation after regenerative periodontal therapy is a common histological observation which is thought to be an artifact. However, several articles have indicated that it can be a serious problem directly related to the weak attachment of the newly formed cementum. The Hypothesis: Tissue separation after periodontal regeneration can be the consequence of losing the fibrous attachment from the cement line between new cementum and the root surface. Evaluation of the Hypothesis: A comparison was made between the cementum–dentin junction, the cement line after root resorption and the cement line after periodontal regeneration because they represent the only means by which the body binds the cementum to root surface. After losing the fibrous attachment from the cement line, the stresses may concentrate at the coronal part of the regenerated tissue leading to the development of tissue separation at that level.