How much intrusion and extrusion can we achieve with aligners?
Answer: Intrusion and extrusion are critical movements in orthodontics, especially for addressing deep bite and open bite cases. Here’s an overview of what can be achieved with aligners:
- Understanding Intrusion and Extrusion:
- Intrusion: Moving a tooth vertically into the gum.
- Extrusion: Moving a tooth vertically out of the gum.
- Case Examples:
- Deep Bite (Left): In cases with a significant lower curve of Spee, the goal is to level the occlusal plane.
- Open Bite (Right): In cases needing vertical closure, extrusion is required to bring teeth into proper alignment.
- Protocol for Intrusion and Extrusion:
- Movement per Aligner: Our protocol allows for 0.1 millimeters of pure intrusion or extrusion per aligner.
- Additional Movement: Besides pure vertical movement, intrusion and extrusion can also be achieved by tipping the teeth. The decision on the best method is made by the orthodontic reviewers based on each case’s specifics.
- Treatment Plans:
- Deep Bite Correction:
- Normal Overbite (10-30%): These cases are treated frequently and typically do not require significant correction.
- Moderate Overbite (30-60%): These cases are common and treated effectively with aligners.
- Severe Overbite (60-100%): These cases can be treated but often require the use of attachments for effective correction.
- Deep Bite Correction:
- Use of Attachments:
- Moderate Overbites: For practitioners preferring fewer attachments, treating 10-60% overbite cases is advisable.
- Severe Overbites: For those comfortable using attachments, treating severe overbites (60-100%) is feasible and often necessary for optimal results.
In summary, with Candid Pro aligners, we can achieve 0.1 millimeters of intrusion or extrusion per aligner. For more significant movements, including severe overbites, the use of attachments may be necessary to achieve the desired outcomes.