Bone plastic jaw

Jaw bone grafting covers operations that restore the shape, volume and continuity of the upper or lower jaw. They are needed when bone has been lost to a cyst, injury, infection or long-term tooth loss. At UKRMED Maxillofacial Surgery, reconstruction is planned by surgeon Anna Kravchenko using CT.

What needs to be restored

A jaw defect is not only "not enough bone for an implant". Reconstruction may be needed:

• after removal of a cyst or benign lesion — see cystectomy;
• after an injury with loss of bone fragments;
• after infection (osteomyelitis) or extraction of teeth with large lesions;
• in severe atrophy after many years without teeth.

When only the tooth-bearing ridge needs rebuilding for a future implant, see alveolar ridge augmentation.

The lower jaw

The lower jaw moves and bears constant load during chewing, so stable fixation is essential: a bone block is secured with titanium screws, and large defects with plates. The mandibular nerve runs along the jaw, and the operation is planned to avoid it.

The upper jaw

The upper jaw is thinner and borders the maxillary sinus and nasal floor. Grafting here is often combined with closure of a sinus communication or a sinus lift. Upper jaw bone is less dense, so healing takes longer.

Diagnosis

CT shows the size and shape of the defect, wall thickness and the position of the nerve and sinus. Based on CT, the surgeon chooses the material and fixation and, if needed, plans the operation digitally.

Materials

• Your own bone — a block or chips from the jaw ramus or chin. It integrates best: in a series of 279 patients, 95.6% of autologous grafts healed successfully.
• Bone substitutes — ready-made material, often mixed with your own bone.
• A membrane — protects the graft from gum tissue ingrowth.
• PRGF — a concentrate of your own plasma for better healing.

The operation

1. Anaesthesia — local or sedation.
2. Access to the defect through a gum incision.
3. Harvesting your own bone or preparing the material.
4. Fixing the block with screws and filling the defect with bone chips.
5. A membrane and watertight closure.

Recovery

Swelling peaks on days two to three and settles in one to two weeks. For the first weeks: soft food, no load on the area and no smoking. A retrospective study of complications found that wound opening over the graft is the most common problem after block grafting, so a watertight suture, check-ups and following the advice are important. The bone matures over 4–6 months, after which implants can be placed.

How to prepare

• Treat decay and gum inflammation — oral infection threatens graft integration.
• Ideally stop smoking several weeks before: smoking impairs bone blood supply and raises the risk of wound opening.
• Tell the surgeon about all medicines. Do not stop blood thinners yourself — the plan is agreed with the prescribing doctor.
• Tell the surgeon if you have taken bisphosphonates or denosumab or had head and neck radiotherapy: this changes the approach.

Contraindications

• uncontrolled diabetes;
• acute inflammation in the mouth or maxillary sinus — it is treated first;
• antiresorptive therapy for cancer or jaw radiotherapy — a high risk of bone necrosis;
• uncorrected bleeding disorders;
• pregnancy — planned grafting is postponed.

Risks and complications

• Wound opening over the graft — the most common problem. Small exposure often heals with careful care; larger exposure needs re-suturing.
• Infection — increasing pain, swelling or pus. See the surgeon.
• Partial resorption — some volume may be lost; material is then added when the implant is placed. In the series mentioned, 4.4% of grafts were lost completely, and most of those patients were successfully re-grafted.
• Pain and numbness at the donor site — when bone is taken from the chin or jaw ramus; lip and chin numbness is usually temporary.

Prices at UKRMED

The surgeon gives the final cost after CT — it depends on the size of the defect and the materials.

When to contact the surgeon urgently

• pain gets worse after day three instead of easing;
• swelling increases, or pus, a bad taste or fever appears;
• stitches open or material or membrane is visible through the gum;
• lip or chin numbness does not ease after a few weeks;
• bleeding does not stop after pressing gauze.

Sources

1. Sakkas A., Wilde F., Heufelder M. et al. Autogenous bone grafts in oral implantology — is it still a "gold standard"? A consecutive review of 279 patients with 456 clinical procedures. Int J Implant Dent, 2017. https://doi.org/10.1186/s40729-017-0084-4
2. Jensen A. T., Jensen S. S., Worsaae N. Complications related to bone augmentation procedures of localized defects in the alveolar ridge. A retrospective clinical study. Oral Maxillofac Surg, 2016. https://doi.org/10.1007/s10006-016-0551-8