**8. Stability and assessment of the results of orthognathic surgery and TJR**

If the quality or absence of joint structures does not ensure the stability of the result of orthognathic surgery, the combination with TJR guarantees a stable longterm result. The authors can confirm this from their own experience: 37 patients underwent orthognathic surgery concurrently with TJR (8 men, 29 women, average age 37, 1 years)- no relapse of DFD was recorded for at least one year after surgery (**Figures 6**–**19**).

**Figure 6.** *28 years old woman with rheumatoid arthritis.*

**Figure 7.** *28 years old woman with rheumatoid arthritis- before surgery.*

**Figure 8.** *28 years old woman with rheumatoid arthritis- frontal view.*

#### **Figure 9.**

*28 years old woman with rheumatoid arthritis- occlusion before surgery.*

**Figure 11.** *CT scan with changes of TMJs.*

**Figure 12.** *28 years old woman with rheumatoid arthritis- Virtual planning.*

**Figure 13.** *28 years old woman with rheumatoid arthritis- Virtual planning, frontal view.*

**Figure 15.** *28 years old woman with rheumatoid arthritis- after surgery- side view.*

**Figure 16.** *28 years old woman with rheumatoid arthritis- after surgery.*

**Figure 17.** *28 years old woman with rheumatoid arthritis- after surgery- frontal view.*

**Figure 18.** *28 years old woman with rheumatoid arthritis- occlusion after surgery.*

**Figure 19.** *28 years old woman with rheumatoid arthritis- occlusion after surgery, side view.*

A number of authors have confirmed this fact in their studies [2, 11, 40–42] both in the stability of CCW rotation associated with TJR [40] and in the number of TMJ pathologies: autoimmune diseases with TMJ - rheumatoid arthritis and juvenile idiopathic arthritis [41], HFM [11], ICR [42].

### **9. Conclusion, summary**

A stable TMJ without signs of pathology is a basic prerequisite for successful orthognathic surgery. If pathology is present, it is necessary to first address the condition of the TMJ (through conservative, mini-invasive and surgical methods). Only after the condition of the TMJ is stabilized is it possible to surgically address DFD.

In the indicated conditions (reduced joint function due to pathological changes of the condyle, reduction of condyle height due to pathological processes in the TMJ, absence of the condyle, TMJ ankylosis or previous unsatisfactory surgical therapy), it is necessary to replace joint structures. Allogeneic patient-fitted prostheses are ideally used for TMJ reconstruction, as the shape of these prostheses allows the lower jaw to be moved to the appropriate position.

Orthognathic surgery in conjunction with TJR is performed in a single operation, where precise planning of these surgical procedures is vital for their successful execution. The patient's cooperation during postoperative care is also an integral part of successful orthognathic surgery with TJR.
