Choosing the right treatment package from clear aligner companies is crucial, especially when addressing vertical discrepancies such as deep bites.
In this blog post, we will explore the various methods and considerations involved in treating deep bites with clear aligners, emphasizing the need for a tailored approach based on the patient's diagnosis and specific requirements.
Understanding Deep Bite Correction:
Correcting deep bites involves a range of methods, including anterior proclination to achieve relative intrusion, pure anterior intrusion and extrusion of posterior segments, as well as levelling the curve of Spee through anterior intrusion and posterior extrusion.
The chosen treatment plan should align with the patient's needs, goals, and anatomical considerations.
Proclining Anterior Teeth for Relative Intrusion:
Patients with significantly upright or retroclined anterior teeth and crowding can benefit from proclining these anterior teeth, resulting in a relative intrusion. This approach helps improve the overbite and establish better anterior stops.
Pure Intrusion for Cases with Good Axial Inclinations:
When anterior teeth have a good axial inclinations or proclination alone is insufficient, pure intrusion can be programmed to further reduce the overbite. Depending on the smile line, the treatment may involve intruding the uppers, lowers, or all anterior teeth to address the deep bite.
Extrusion in Cases with a Reduced Vertical Dimension:
If a patient with a reduced vertical dimension has a Deep Bite, extrusion of the posterior teeth, mainly the premolars, will be required to improve the overbite and increase the vertical dimension. Posterior extrusion leads to mandibular rotation, resulting in a decrease in overbite.
In general 1 mm of posterior extrusion leads to an increased anterior opening/decrease in the overbite of approx. 1.5-2.5 mm's.
The long term stability of theis type of treatment is somewhat controversial, as it will often be the muscles that define the vertical dimension. Over time a relapse should therefore potentially be expected.
Predictability of Treatments:
The predictability of deep bite treatments varies based on the required intrusion and extrusion. Absolute intrusion of about 2 to 2.5 mm is considered the most predictable, while more complex cases with over 3 mm of anterior intrusion and over 1 mm of posterior extrusion may require additional support.
Considerations in Treatment Planning:
Assessing the smile line and smile arc is crucial in prescribing the correction method. Treatment strategies may involve intrusion of only the anterior teeth or a combination of anterior intrusion and premolar / molar extrusion.
Anchorage, retention & movements
Attachments / Engagers and bite ramps are essential for anchorage, retention, and preventing unwanted tooth movements during treatment.
When intruding the anterior teeth, aligners may disengage on the posterior teeth, following Newton’s 3rd Law: "Every action has an equal and opposite reaction".
Premolar and molar attachments or engagers
To mitigate disengagement & ensure the effectiveness of correction, plan for attachments on the Premolar region, to provide anchorage & retention for anterior intrusion.
In cases where premolar extrusion is part of the strategy to level the curve of Spee, these attachments also play a key role in delivering extrusive forces to the premolars as well.
Bite block effect
Practitioners must take into account the potential bite block effect inherent in the aligners. As these aligners cover the occlusal surfaces of the teeth, patients will naturally occlude on them. This can induce unwanted posterior intrusions, posing a potential challenge to the efficacy of deep bite correction.
Bite ramps
In cases where premolar extrusion is deemed necessary within the treatment plan, it is advisable to incorporate bite ramps to achieve posterior disocclusion.
Bite Ramps facilitates posterior extrusion, eliminating any undesired posterior bite forces that might otherwise counteract a deep bite correction.
The placement of these bite ramps can be meticulously planned on either the incisors or the canines, providing crucial support for significant lower anterior intrusion.
Avoid bite ramps in these instances
In instances where the overjet exceeds 3mm, it is recommended to avoid placing bite ramps on the incisors & consider placing them on canines instead (if possible). This precautionary measure is essential as patients may inadvertently bite behind the ramps, exacerbating the overjet by causing flaring of the incisors.
Software considerations
Clear aligner software does not depict the evolving appearance of patients' teeth on a weekly basis during treatment; rather, it illustrates how aligners will be manufactured for each stage of the treatment process.
Aligners serve as advanced archwires that patients independently change weekly; for enhanced predictability, especially in complex deep bite cases, incorporating a reverse curve in the digital plan—consisting of 3 to 3 intrusion, 4 to 6 extrusion, and intrusion of 7s— may improve treatment outcomes.
Monitoring and Adjustments:
Regular monitoring of interproximal contacts is essential to ensure sufficient space for intrusion. Incomplete anterior intrusion may lead to premature anterior contacts, a common cause of posterior open bite.
Careful monitoring of planned movements on lateral incisors is essential, as they have a tendency to lose tracking easily.
Conclusion:
Addressing deep bites with clear aligners requires a customized approach, considering the specific needs of each patient. By understanding the different correction methods and incorporating careful treatment planning, orthodontic professionals can achieve successful outcomes in deep bite correction with clear aligners.
Kind regards
Priyanka Cherian DDS
AlignerService helps dentists create realistic, safe and predictable treatment plans with clear aligners.
Currently, we help approximately 1500 dental practices in 19 different countries. AlignerService is a preferred partner of ClearCorrect and TrioClear.
In addition AlignerService clear aligner experts work with Invisalign, SureSmile, Angel Aligners and Spark.