Prerequisites for Aligner Therapy

At a Glance

For Patients

Before treatment with clear aligners comes a thorough examination – from the medical history through the function of the temporomandibular joint to the X-ray findings. The article shows what matters here and follows a documented treatment case.

For Professional Colleagues

Requirements for diagnostics and treatment planning in aligner therapy, with a case report of an adult patient.

Suitable Treatment at Our Practice: Clear Aligners

What an Aligner Treatment Requires Professionally

Clear aligners have become an established part of orthodontics. With their widespread adoption, however, the number of providers has also grown – extending to commercial offerings that sell treatments directly to patients without professional supervision. The underlying peer-reviewed publication from our practice addresses the question of what professional requirements an aligner treatment needs and demonstrates the process using an actual treatment case. Below, we summarize the key points in accessible language.

Can Every Misalignment Be Treated with Aligners?

The publication begins with exactly these questions: Can every patient and every dental or jaw misalignment be treated with aligners? Are there limits? And can a commercial provider deliver this as well?

First, it should be noted: After more than 20 years of experience, aligner treatment has become an established component of the orthodontic treatment repertoire. While the initial scope was mainly smaller gaps and crowding, careful planning today allows for more demanding corrections in horizontal, vertical, and sagittal directions – in adults as well as in younger patients. The decisive factor is that individual biological conditions and biomechanical principles are taken into account.

Diagnostics Before Treatment

As before any orthodontic treatment, a comprehensive initial diagnostic workup is required here as well. The publication describes five components.

Medical History

Among other things, the clinician asks whether genetic factors contribute to the misalignment, whether systemic diseases or particular pain symptoms are present, and whether medications are being taken that could influence tooth movement.

Extraoral and Intraoral Examination

This includes the biological analysis (condition of the periodontium, endodontium, and enamel and dentin), the myofunctional analysis (habits, abnormalities in speech and swallowing patterns, lip seal, breathing), and the esthetic analysis – such as the resting position of the upper lip in relation to the incisors, the dental and skeletal midline, gingival display, buccal corridor, and the course of the smile line.

Functional Diagnostics

The “Short Screening” according to G. Meyer is used to check for signs of temporomandibular disorder (TMD, often called TMJ). Six individual examinations are employed. If two or more tests are positive, TMD is likely and further functional analysis is indicated. If TMD goes undetected, problems can arise during and after treatment, including worsening of the disorder.

Model Analysis

Model analysis provides insights into the structural conditions. In adult patients, not only misaligned teeth but also missing teeth and defective restorations should be considered in order to plan interdisciplinary treatment if necessary.

X-ray Findings

A panoramic X-ray is used to determine the number and position of teeth, mineralization, shape and size of tooth buds and roots, as well as to assess tooth roots, jawbone and periodontium – and for caries diagnosis.

Basic Principles of Treatment Planning

For planning purposes, the publication lists several basic principles: Without anchorage, correct tooth movement is not possible. A tooth that does not need to be moved should not be moved – micromovements of molars should be avoided. In the lower jaw, the intercanine distance should be maintained, as this promotes the stability of the treatment result. And “round-tripping,” i.e., moving teeth back and forth, should be avoided.

A Treatment Example

The Initial Situation

A 46-year-old patient presented for the first time at our practice in December 2021. She had already been treated as a teenager with fixed braces; at that time, tooth 24 was extracted and the gap was closed. The “Short Screening” test was negative. Clinically, gum recession was evident, especially in the upper jaw, most of which had already been treated with cervical fillings. There were additional restorations, a history of root tip resection, and a mild horizontal bone loss.

The Planning

After consultation with the referring dentist, it was agreed that the replacement of the inadequate restorations would be performed following orthodontic treatment. Before and during the treatment, periodontal treatment was performed so that tooth movements could take place in an inflammation-free periodontal apparatus.

Due to the gum recession, gaining space through further expansion or forward inclination of the teeth had to be avoided; instead, space in the lower jaw was created by careful interproximal enamel reduction between the teeth. An elaborate correction of the midline in the upper jaw was deliberately not planned: The patient was not bothered by it, and the stable occlusion in the posterior region was to be preserved.

The planning was done virtually in the OnyxCeph software. The molars were fixed so that they remained unmoved for anchorage purposes and to preserve the stable occlusion. On teeth 33, 43 and 31, rectangular, vertical retention elements (attachments) were planned in order to optimally transfer forces.

The Course of Treatment

The planned tooth movement resulted in twelve treatment steps. The aligners were fabricated in our in-house laboratory. The patient changed the aligners weekly and wore them 22 hours daily; a check-up appointment took place approximately every eight weeks.

After the first treatment phase of 24 weeks, the dental arches were largely formed. Tooth 31 still showed a slight rotation and misalignment, which is why an additional phase with four further steps in the lower jaw was planned.

The Result

After a total treatment time of eight months, the dental arches were harmoniously shaped and the crossbite in region 13 was corrected. The gum recession that already existed at the beginning had not worsened, and the signs of inflammation in region 11 were decreasing. The planned interdisciplinary dental follow-up treatment could then begin. To secure the result, the patient wore a retention splint in the upper jaw at night; in the lower jaw, a lingual retainer was placed from tooth 34 to 44.

What This Case Shows

Aligner therapy is an esthetic and comfortable treatment option for patients that can achieve very good results when applied by specialists. To avoid undesirable side effects, adequate diagnostics and treatment planning based on biomechanical principles are necessary. There are many potential sources of error – therefore, every specialist should critically question themselves with every treatment.

You can learn more about treatment with clear aligners on our dedicated page, more about orthodontics for adults and TMD pain therapy in the respective sections. How we perform diagnostics in-house is explained under Digital Diagnostics.