Block Graft
Retro-molar Area
Luca de Stavola 2021
Block Graft
Retro-molar Area
Luca de Stavola 2021
HARVESTING/ DONOR SITE
Mostly on the external oblique ridge of the mandible.
EXTERNAL OBLIQUE RIDGE
Individual variability.
The more lateral and prominent it is, the better and safer to harvest.
Palpation to feel the horizontal bone volume.
Access incisions
(see pictures 1 to 8 below).
(7'52'')
(9´07'')
(19'55'')
Buccal located incision starting high on the beginning of the vertical projection of the coronoid process, it extends mesially, generally to the level of the first molar (depending on individual variability), 2 or 3mm apart from the marginal gingiva of teeth.
Establish the trajectory of the inferior alveolar nerve.
Distally we have a limitation represented by the vertical projection of the coronoid process, in this area the nerve will be, most of the times, very superficial
Mesially the limitation will depend a lot on individual anatomical variability.
BONE INCISIONS
The vertical distal incision:
(5'21'')
Maximum safe depth about 3 mm.
Anterior to the anterior border of the coronoid process of the mandible, ideally it should be done within the vertical projection of the coronoid process. However we should be aware of the fact that it will be easy to perform it perpendicular to the top of the bony plateau we're harvesting, this will make this bone incision run way more distally than it should, falling out of the safe zone for harvesting and getting closer to the nerve and to the danger area.
The mesial incision
Maximum safe depth about 3 mm.
Paralell to the distal incision.
Apical incision/ Apical osteotomy
(8'44'')
Maximal depth of 2mm, you should stay superficial.
This connects both mesial and distal incisions.
Cranial/Coronal incision
We connect the mesial and distal incision cranially, using a 1mm drill, perforating the cortical and getting the feel when you reach the medular bone. This very important because on some parts of this area the nerve can be more superficial.
The chisel must not penetrate in the bone and it promotes the fracture.
NERVE TRAPPED IN THE BLOCK
(13'43'')
