Although it permits the insertion of thin and/or extremely inclined implants, the presence of a moderately thin crest in the premaxilla area certainly compromises the final aesthetic result of rehabilitation with implant prostheses, making it therefore advisable to use surgical regeneration procedures.
If instead the crest is very thin (< 3 mm), implant insertion is impossible without using regenerative surgery.
Essentially, there are three surgical techniques to increase the thickness of thin crests available to implantologists:
- Block grafts with vestibular fixing;
- GBR with non-resorbable membranes or titanium mesh;
- Split-crest techniques.
Our therapeutic choice, whenever possible, is for a split-crest technique, which in our experience has the following advantages in comparison to other techniques:
no bone harvesting necessary (reduction of morbidity post-operative);
- very predictable bone healing, as the volume to be regenerated is located between two viable bone walls;
- improved quantity and quality of the keratinized peri-implant gingiva;
- possibility of inserting implants at the same time (reduction of number of operations and total time).
The split-crest technique applied to particularly thin crests has always been a difficult task, even for the most experienced surgeons, especially when the classic instruments are used (hammer and chisels).
The introduction of the Magnetic Mallet has without doubt made split-crest procedures simpler, quicker and more precise. In fact, among the countless clinical advantages of this instrument, what makes it so decisive in a split-crest procedure is the great two-handed control over blade inserts and osteotomes that it gives, at a level unachievable with the standard hammer technique. The cutting precision offered by this instrument is, in our opinion, of great assistance for less-experienced practitioners of split-crest techniques, and even gives experts great advantages.
With the ample photographic documentation accompanying this case report involving a very thin crest, we hope to be able to share our split-crest protocol, used for many years in numerous clinical cases of varying levels of complexity.
In a later article we intend to discuss the contraindications for split-crest procedures (crests consisting entirely in cortical bone, crests thinner that 2.5 mm, grade IV crests), alternative techniques for these cases, and the management of intra-operative complications (rescue techniques in case of vestibular cortex fractures).
