Gingival blood supply
There are four gingival blood supply systems interconnected and running in an apical to coronal direction (Bone marrow intraseptal arteries perforate the bone cortex and become the supraperiosteal plexus. These vessels of 100-nanometer diameter penetrate the submucosa and, just below the basal layer of the epithelium, form the subepithelial plexus that extends, in the tooth area, along the sulcular epithelium joining the periodontal ligamental arteries.
- Bone marrow intraseptal arteries penetrate the cortical plate and anastomose with the supraperiosteum vessels in the reticular layer.
- The supraperiosteum vessels in the reticular layer send terminating branches superficially to form the subepithelial capillary plexus in the papillary layer.
- The subepithelial capillary plexus in the papillary layer sends coronal branches to the marginal gingiva, forming a capillary plexus under the marginal gingiva, along the sulcular epithelium and the apical extension of the junctional epithelium.
- They join with the periodontal ligament that supplys the marginal and interdental gingiva.
Fiber groups of the marginal periodontium
The main fiber groups of the marginal periodontium attach the soft tissue to the bone and cementum. Their directions and functions are described (Principal fibers of the marginal periodontium. The gingival ligament fiber groups include the dentogingival, dentoperiosteal, alveologingival, circular and transseptal fiber groups).
The horizontal incision begins with the intrasulcular incision that extends from the gingival sulcus
, through the fibers of the dentogingival union up to the crestal bone
. The remaining tissue in the interdental space facilitates the flap papilla reattachment and prevents loss of soft tissue attachment.
The vertical incision starts perpendicular to the line angle of the tooth up to the middle of the base of the papilla, and then turns to follow vertically and sever perpendicularly fiber lines of the attached mucosa and periosteum between bone eminences.