# Case Review: Class 3 Patient Insights 🦷

# Question:

I had a question about lower SD (let me know if there's some place else I should ask / read ); I had a patient class 3 18 year old male where I did lower SD and class 3 elastics. After the first round, he was class 2 so we had to switch the elastics around. Did the lower SD work because he potentially could have still been growing or did the class 2 happen because of jaw positioning? (I was wondering about SD because I was wondering how I could use it in other cases such as for my 16 year old)  
<https://shub.invisalign.com/cc-cloud/latest/index.html?locale=en_US&user=user&ccModIntegrity=false&configUrl=%2Fconfig%2Fscsl_cc_cloud&ccId=524328> 


# Answer: 

[Case Review: Class 3 Patient Insights 🦷 - Watch Video](https://www.loom.com/share/0cb8185b5e594e23a3e07050319faea7)

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This case involves a Class 3 patient with an initially tight bite. The patient's facial profile is not strongly Class 3, and the treatment plan includes sequential distalization from the lower canine to the lingual of the upper sixes.

#### **Observations:**

* The initial overjet was predicted at 2.2 mm but resulted in 2.5 mm.
* The patient appears more Class 2 due to premature palatal cusp interference, which is propping the bite open.
* Sequential distalization, elastics, and potential late mandibular growth all contributed to the outcome.
* The occlusal vertical dimension has changed, likely affecting mandibular positioning.
* While the lower canine is Class 1, the molar started as Class 3, and bite opening shifted mandibular positioning toward Class 2.

#### **Treatment Plan:**

* **Sequential Distalization:** Facilitated space creation and occlusal correction.
* **Class 3 Elastics:** Likely contributed up to 2 mm of movement.
* **Occlusal Adjustments:** Managing palatal cusp interference to avoid a pseudo-Class 2 effect.
* **Vertical Dimension Considerations:** Changes in occlusal height influenced mandibular positioning and should be monitored.
* **Root Torque Adjustments:** Increasing palatal root torque and selectively intruding lower teeth where needed.

#### **Additional Considerations:**

* Overuse of Class 2 elastics could result in excessive bite tightening.
* IPR between premolars may be beneficial for better occlusal fit.
* Monitoring canine intrusion is necessary to maintain comfort and functional occlusion.

By addressing occlusal interferences and vertical dimension changes, this case demonstrates the importance of balancing distalization, elastic wear, and torque adjustments to achieve an optimal final bite.