Using light-force mechanics to address severe crowding
Lingual orthodontics is again surging in the United States. It first gained steam in the 1980s, but the love affair with lingual ortho has ebbed and flowed over the past 40 years—the most recent cycle of interest, featuring highly customized systems from Europe, ended with the rise of plastics.
Increased marketing efforts from clear aligner companies and improved results using plastics with difficult cases led many orthodontists who’d been treating cases with lingual appliances to begin new patients with aligners. Still, many patients cannot tolerate the compliance of clear aligner therapy and prefer a fixed aesthetic appliance. In the past five years, lingual orthodontics has again captured our attention as we look to provide highly aesthetic treatment with a fixed appliance.
Principally credited for the renaissance are two innovative U.S.-based companies, InBrace (Fig. 1) and Brius (formerly Mechanodontics, Figs. 2a and 2b), and two new straight-wire systems, Lingual Liberty by French orthodontist Dr. Didier Fillion and Alias out of Italy and Japan from Ormco (Fig. 3, p. 38). All of these newer systems attempt to simplify and streamline lingual treatment by adding convenience and efficiency to the setup and delivery process, making it similar to clear aligner treatment planning and execution.
If you’re already thrilled with your aesthetic options, such as labial ceramic fixed brackets or your aligner du jour, then lingual orthodontics may not be worth your time and investment. However, you might consider exploring one of these new lingual options if your aligner cases are leaving you stressed with overdue estimated treatment times, inability to complete complicated movements, or intricate detailing. Some patients are intolerant of labial brackets or attachments on anterior teeth, and lingual is an excellent aesthetic option for them.
Here are some of the most important considerations before jumping into lingual:
Delegation. Especially while introducing lingual appliances to the practice, treatment cannot be delegated nearly as well as clear aligners or labial fixed to your wonderful assistants. If you’re under any illusion that you’ll be able to add this treatment to your arsenal without getting your hands dirty, you’ll be sorely disappointed. Yes, the initial records are the same, and uploading them to the labs is not difficult. Even virtual planning of lingual treatment is quite similar to the setups you’re familiar with for aligners.
That, however, is where the parallels diverge. The indirect bonding delivery of the brackets and wire insertion requires new skills, and initially will require more time and planning to execute. It’s appropriate to block out two hours for your first few indirect lingual bondings with two assistants available and few if any other patients scheduled. Most traditional lingual orthodontists bond just one arch per appointment, as well. This added time and elimination of distraction will allow you to attend exclusively to a critical step in the treatment process.
As you and your team complete a half-dozen or more successful indirect lingual bondings, you can reliably begin to delegate most of the process, although you may still consider delivering the bonding tray each time to ensure the highest levels of adhesion. If you think broken brackets on the labial are frustrating, you can’t imagine what broken lingual brackets will do to your temperament! Even with staff reluctant to change or add something new, I’ve found that my enthusiasm has transferred to the team, and any difficulties we may experience can be balanced by hands-on assistance from the doctor.
Managing patient expectations with lingual treatment is critical. Be clear with patients that their speech will be affected, though most adapt well after a few weeks—most young adults adjust within a month, older adults by eight weeks. Occasionally, an isolated patient can be discouraged by a lack of full speech adaptation, but it’s likely more due to hyper-self-awareness than an actual communication impediment.
Tongue pain can be hard to bear with lingual treatment and I clearly explain it will be difficult to tolerate for two weeks. In my experience, though, the pain is not significantly different from labial buccal mucosa pain and can be managed well with wax (especially at night) or other temporary composite coverings. Remember to tell patients that labial attachments will be needed in many cases. If you have to prescribe elastics, resolve crowding or bail yourself out of a jam, you might need a labial attachment or bracket. Make sure patients are aware of this potential ahead of time.
Check the lingual surface of teeth before you recommend lingual treatment. The surface should be occlusal-gingivally large enough for a bracket and free from large extra cusps. It must be free of calculus buildup. You may want to perform some enameloplasty pre-scan to allow for a smoother bonding surface with the indirect setup. Remind patients that they can’t get any dental treatment before the delivery of the appliance, because of potential fit issues it may cause. Finally, make sure patients aren’t getting married or having other major life events the week after bonding for risk of speech or discomfort issues.
Check all interproximal contacts after bonding. Because the interbracket distance is much shorter on the lingual side, it’s easier to get bonding and composite stuck between teeth after lingual bonding, which can compromise movement initially.
Especially for your first few lingual cases, take photos at each visit and see patients at least every month. I prefer to work on just one arch at each appointment and haven’t found it slows the treatment down. Having regular photos helps you track progress more closely and plan for future visits, which increases efficiency and maximizes your chair time.
Finishing has always been one of the most difficult parts of lingual treatment. Because most of us were trained in a straight-wire labial fixed technique, we’re used to repositioning brackets for better finishing. Repositioning of brackets is possible but difficult with lingual, which places increased reliance on the initial setup and virtual treatment planning. The options for finishing after repositioning brackets or standard manual wire customization are rescanning the patient for additional wires, labial auxiliaries, or many doctors are finishing cases with a few clear aligners. Again, make sure you prepare yourself, your team and your patients for the finishing and detailing parts of treatment by planning ahead of time which approach you’d like to take.
Caveats and limitations
• As previously mentioned, lingual treatment is “harder” than clear aligner therapy from both a clinical and patient perspective. Bonding clear aligner attachments is much easier than indirect fixed lingual bonding of brackets. Understandably, clear aligners are more comfortable than a lingual fixed appliance. There are more emergencies and oh-shoot-what-do-I-do moments with lingual treatment. But remember, grit. Always grit.
• Some of the newer lingual systems mentioned previously may not be predictable for severe cases. Many patients who need extraction treatment, TADs or other complicated mechanics cannot predictably be treated without a more robust lingual appliance. For these cases, a fully customized system is preferable, such as eBrace (China), Lingual Liberty (France/USA), Incognito (Germany) or SureSmile (USA, wires only).
• Unless you’re willing to learn how to perform in-house indirect bonding well, you will need the help of a lab to set up cases. This dependence on a lab can initially be dissuasive for doctors mainly familiar with direct-bonding-only labial fixed appliances. The easier the communication with the lab, the less frustration and better outcomes when problems arise.
• Patients may need some convincing of the benefits of a lingual appliance. Most patients are already familiar with and request clear aligners, so encouraging them to select a different appliance may be difficult. You must identify why patients are particularly requesting clear aligner therapy and see if, in fact, they are motivated by the unique characteristics of plastic or they just want an aesthetic appliance. I focus on aesthetics, compliance and finish quality when discussing the advantages of fixed lingual treatment.
This young adult presented with relapse from treatment as a teenager. I used an InBrace appliance with minimal IPR over seven months. After initial tissue healing with a
removable clear retainer, a lower fixed retainer was subsequently placed.
• Nothing is more aesthetic than fixed lingual orthodontic treatment—no removing trays in public, no anterior attachments and, often, no labial attachments at all.
• Fixed appliances may leave more in your control as a clinician and less to the winds and whims of patient compliance. Better control typically translates to more predictability, efficiency, high-quality results and happy patients.
• As clear aligner treatment is increasingly provided by nonspecialists, it is appropriate to have an aesthetic option that clearly identifies you as the master of your domain.
I’d encourage you to explore the option of adding a lingual fixed appliance to your arsenal. The newer lingual companies have wonderful customer service and can help the uninitiated successfully onboard a new treatment option in their office. I’ve been thrilled with the lingual treatment we’ve performed and look forward to encouraging more aesthetically inclined patients to use it. Ultimately, with patience, attention and practice, you’ll succeed in providing your patients another aesthetic treatment option.