Pre-treatment Conditions to Consider

Some variables can affect clear aligner treatment and make it unpredictable. These variables are specific conditions that require consideration when planning treatment. 

On-screen now is a file that contains a few of your patients that you are considering for clear aligner treatment. First, you need to assess their current condition.

Please note: The presence of these conditions does not prohibit treatment but should be considered before starting. Cases, where they are present, should be avoided until one has more experience.

• Missing Teeth: The patient has multiple missing teeth which can create too much retention making the aligner difficult to remove. This also reduces anchorage options.

Tip:

1. Anterior Teeth: In the setup process, ODONTO will fill gaps with simulated teeth.
2. Molars: Technicians can construct a "bridge" between any large space.

• Short Clinical Crown: The patient has short clinical crowns which can cause poor aligner retention This makes it difficult to seat the aligners, place the engagers and move the teeth.

Tip:Indicate any short clinical crowns and request engagers on the first or second premolars under the "Additional Instructions" section of your case submission.

• Poor Oral Hygiene: The patient has poor oral hygiene. Orthodontic tooth movement involves complex biological mechanisms of bone and soft tissue remodelling, inflammation and healing. These processes may be disrupted by poor oral hygiene resulting in harm to the patient with some complications of:

-Decalcification 

-Caries 

-Recession 

-Gingival inflammation 

-Periodontal disease

Tip: Treat pre-existing conditions related to poor hygiene before starting clear aligner therapy.

• Dental Prosthetics/Implants: The patient has dental crowns which make the bonding of engagers challenging. A patient may also have other dental prosthetics such as:

-Implants which cannot be moved but can be good for anchorage.

-Bridges which can create undercuts that may make it difficult to insert or remove the aligners due to too much retention.

-Dentures which are designed to fit together with the opposing arch. If any of the teeth move, the dentures will probably need to be replaced or adjusted.

• Severe Bruxism: The patient has severe bruxism which can quickly wear down the aligner or displace them so that they do not function properly.

Harmful dental habits are most common in children but sometimes they persist into adulthood.

Bad news: It's usually extremely difficult for adults to break a habit. These habits interfere with movements and increase the chance of relapse after treatment.

Good news: Once you learn to recognize these habits you can be prepared, choose appropriate cases to treat and set realistic expectations with the patient. Work with your patients to manage their condition.

After recognizing the habits, appropriate referrals for myofunctional therapy can improve long-term results by correcting any myofunctional dysfunctions.

• Second Molar Missing: The patient has her second molars missing which means that:

-Distalization of the first molar is unlikely to occur.

-If under eruption, watch for supereruption because the aligner will not stop the eruption from occurring.

-Short clinical crowns and bite discrepancies in deciduous dentition can make treatment difficult.

• Active Periodontal Disease: The patient has active Periodontal Disease. Progression of the periodontal condition/disease may be possible while the teeth are moving during treatment. Patients with active periodontal disease are less likely to respond positively to the osteoblastic and osteoclastic activity that occurs with tooth movement during treatment.

Tip: Address pre-existing conditions before starting clear aligner therapy.

• Difficult Movements: The patient has a dental condition which requires movements that are difficult to achieve with clear aligners, such as:

-High-degree rotations

-Significant intrusion and extrusion

Tip: If you wish to treat cases that require movements that are considered difficult, be sure that you know how to use auxiliaries with clear aligners and are familiar with the techniques to aid with these types of movements.

• CO and CR Variations: The patient has centric occlusion (CO) and centric relation (CR) variations which may result in:

-A forced unilateral crossbite

-TMD symptoms

-The added risk of posterior open bite at the end of treatment

The condyle is positioned in the fossa on the retrodiscal tissues, with the disc remaining anterior to the head of the condyle.

During transitions, the disc is further misshapen thereby restricting the full opening of the mandible.