The document discusses reconstruction of the temporomandibular joint (TMJ), specifically the use of costochondral grafts and fibula grafts for condylar replacement. Costochondral grafts, which consist of bone and cartilage from ribs, are commonly used for TMJ reconstruction when severe joint destruction or ankylosis has occurred. Autogenous tissues like ribs, clavicles, and fibulas can be used in TMJ reconstruction, with costochondral grafts being the most frequent choice. The document outlines the surgical procedure for harvesting and implanting costochondral grafts for TMJ reconstruction.

1. TMJ Reconstraction

2. • When severe destruction or ankylosis of the temporomandibular joint occurs, joint replacement may be
necessary. Although there are a number of autogenous sites that have been used over the years, the
costochondral graft is the one that is most frequently employed. Alloplastic joints are now available and
there are a handful of different types that are manufactured and commercially available. Most are similar to
orthotopic alloplastic joints in that they are often made of titanium with a chrome/ cobalt surfaced head
and an ultra-high molecular weight polyethylene glenoid fossa. This chapter will describe the indications for
joint replacement and the materials and techniques available.
• TMJ reconstruction is not a treatment for general TMJ problems, but rather considered end-stage surgery
and a more exclusive treatment modality.
• The term "TMJ reconstruction" should be used when both the condyle and the fossa are reconstructed. If
only one component is reconstructed, terms such as "condylar replacement" or "fossa reconstruction"
should be used, respectively.
• In TMJ reconstructive procedures, the choice can be made between using autogenous (from the patient's
own body) material or alloplastic (synthetic) devices.

3. • • Indications for TMJ reconstruction include:
• 1- severe degenerative joint disease
2- bony ankylosis
3- irrepairable condylar fracture
4- neoplasia requiring joint component resection
5- congenital malformation
6- previously failed reconstruction.

4. Autogenous reconstruction
• Autogenous donor tissues used for condylar replacement include:
1- metatarsal
2- clavicle
3- iliac crest
4- vascularized fibula
5- ribs:

5. • Costochondral grafts consist of both bone and hyaline cartilage.
• - The adaptability of rib grafts and their cartilage to local conditions is relatively easy.
• - In non-skeletally mature patients, costochondral grafts may have some growth potential, which can be an
advantage.
• - However, the growth potential can also be a potential disadvantage as the graft may grow too much, too
little, or not at all, requiring further surgical procedures to correct the jaw position later on.
• - Costochondral grafts are relatively reliable in many instances but may not be overly reliable in treating TMJ
ankylosis.
• - A preoperative diagnosis of ankylosis is associated with increased complication rates and the need for
further surgery, suggesting caution in this group of patients.

6. • - Common downsides of costochondral grafts include:
• 1- ankylosis/reankylosis
2- resorption
3- donor site morbidity.

7. Costochondral grafts for condylar replacement

8. • Costochondral grafts are usually used as free, non-vascularized grafts.
• The protocol for management of TMJ ankylosis involving costochondral grafts consists of seven stages:
• 1- aggressive resection
2- ipsilateral coronoidectomy
3- contralateral coronoidectomy when necessary
4- lining of the TMJ with temporalis fascia or cartilage
5- reconstruction of the ramus with a costochondral graft
6- rigid fixation
7- early mobilization with aggressive physiotherapy.

9. • Enlargement of the coronoid process may occur with TMJ ankylosis and can interfere with mandibular
mobilization. In cases where the condyle is replaced for reasons other than ankylosis, such as
rheumatoid arthritis, the coronoid process may be left untouched.

10. • Surgical access to the TMJ area for costochondral replacement requires two approaches: one
preauricular and one retromandibular or subangular.

11. • Rib harvest is typically performed through a horizontal incision below the inferior border of the
pectoralis muscle, usually from rib number five, six, or seven. It is important to examine the tissue bed
for any signs of pleural tear.
• After making the incision and dissecting through the skin and subcutaneous tissues, the periosteum is
cut parallel to the rib. A subperiosteal dissection is carefully performed around a 4-5 cm length of the
rib. Approximately 1 cm of the hyaline cartilage (rib's end) is sufficient to serve as the condylar head. It
is important to leave a strip of periosteum or pericondrium (connective tissue) around the junction of
the rib and cartilage to provide support and prevent separation.

12. • The rib is preferably cut using a specialized rib cutter, allowing as much rib as the incision allows. After
removing the rib, the tissue bed is examined for any signs of pleural tear, which may cause bubbling in
the saline-filled wound. If a tear is present, it should be closed. A chest radiograph is obtained
postoperatively to ensure no pneumothorax (air in the chest cavity) is present.
The cartilage part of the rib can be carved to fit optimally into the fossa. Fixation of the costochondral
graft may involve screws, plates, or steel wires.

13. • Intermaxillary fixation (IMF) is recommended for a period of time, ranging from 3-10 days to 4-6
weeks, depending on the thickness and rigidity of the costochondral graft.
• After the release of maxillomandibular fixation, the patient can start a soft diet and perform jaw-
opening exercises. Heat, massage, ultrasonography, gum chewing, and manual stretching exercises can
be used to increase the opening capacity achieved during surgery. Tissue stretching under general
anesthesia may be considered if the desired degree of opening cannot be reached with physical
exercises.

14. Fibula grafts for condylar replacement