By Dr. Norman Bach
Invisalign® clear aligners have become an increasingly popular choice for adults and teens who want to avoid the awkward appearance of traditional braces. Invisalign® has been shown to be an effective orthodontic treatment choice for the majority of adult and older teen patients, including those with increased overbite, crossbite, underbite, gapped teeth, open bite, and crowding.
Since Invisalign® costs are only a little bit more expansive than traditional metal or clear braces and can treat the majority of cases, it’s no wonder that so many patients are eager to try it. However, it’s important to be aware that not every patient is a good candidate for Invisalign® . Here are some situations where Invisalign® may not be an appropriate choice:
- Large or severe overbite
While Invisalign® is effective for many cases of overbite, it is not designed to treat overbite that is severe. For cases of severe overbite or skeletally-based malocclusion, a more advanced orthodontic procedure may be needed to correct the jaw. Metal or clear braces may also be a better choice for severe overbite.
- Children or young teens
Invisalign treatments for young adults® allows them the freedom to participate in school and social activities without having to worry about their appearance. However, Invisalign® will not work effectively when the patient’s teeth have not stopped growing yet. Invisalign® is generally a good choice for patients of high school age and older, while younger teens and children should be treated with metal or clear braces.
- The patient is unmotivated or uncooperative
Most patients consider Invisalign® to be a relatively comfortable and easy treatment option. Invisalign® is unique in that patients are required to remove their aligners when eating or drinking. The patient must replace them immediately after mealtime.
Invisalign® aligners must be worn 22 hours per day or they will not be effective. Many patients are reluctant to wear and care for their aligners as directed, causing the teeth to shift back to their original positions. This can result in lengthened cost and treatment time for the patient. Before starting treatment with Invisalign®, consider whether the patient is willing and able to follow all treatment guidelines.
- Tipped or rotated teeth
Teeth angled more than 45 degrees from normal are unable to be effectively treated with Invisalign® . Severely rotated teeth of more than 20 degrees from normal, particularly premolars and lower canines, are also unlikely to benefit from Invisalign® treatment.
- Invisalign® will not eliminate the need for tooth extraction
Just as with metal or clear braces, teeth may need to be extracted in order to create extra space before treatment with Invisalign® if overcrowding is an issue. In some cases, Invisalign® is not recommended when teeth have been extracted as the appliance cannot keep the teeth upright during space closure.
- Crown shape
Crowns that are unusually short, pegged, or round will be difficult to manipulate using Invisalign® aligners.
- Preexisting dental work
Teeth must be in generally good repair before beginning Invisalign® treatment. Previous treatment with a bridge will often make Invisalign® treatment more difficult.
- Increased risk of cavities
One of the many benefits of Invisalign® is that patients remove their aligners before eating and can clean their teeth and aligners before replacing them. This is an advantage over braces, where food particles can often get stuck. However, in patients who are noncompliant with removal and cleaning directions, food can become trapped underneath the plastic aligners, creating the perfect environment for bacteria growth and cavity formation.
It is very important that this risk, as well as removal and cleaning instructions, be discussed thoroughly with the patient. Patients who are unlikely to comply with cleaning guidelines are not good candidates for Invisalign® .
- Periodontal problems
Gums should be in good health prior to starting Invisalign® treatment. Since the aligners move the bones there is increased risk of tooth decay and loss if periodontal disease has not been resolved before beginning Invisalign® treatment. Patients should receive clearance from a periodontist prior to Invisalign® treatment if there is any question of periodontal disease.
Again, it cannot be stressed enough that while part of the beauty of Invisalign® lies in giving patients control over their appearance and dental hygiene, it is absolutely imperative that patients receive adequate education about caring for their teeth and aligners during treatment. Patients who do not follow the treatment guidelines as directed are at increased risk of tooth decay and damage. That said, Invisalign® is a cost-effective, aesthetically-pleasing treatment which can meet the needs of most patients.
About the Author
Dr. Normand Bach received his dental degree from the University of Montreal in 2002, and completed a certificate of multidisciplinary residency at Notre-Dame Hospital in 2003. In 2008, Dr. Bach completed a Master’s Degree of Science and a Certificate in Orthodontics at the University of Montreal. He is currently an Associate Professor at the University of Montreal and is responsible for the undergraduate orthodontic clinic, in addition to maintaining a private practice limited to orthodontics in Montreal. http://orthodontistemontreal.com/