Hardly a day goes by that a parent will not ask about their own teeth at their child's orthodontic appointment. They are curious about options for aligning their own teeth and improving the esthetics of their smile. Typically, this is immediately followed up by the comment "I had braces as a teenager, but of course, I stopped wearing my retainer and then…”
There is no doubt in my mind the majority of these questions are asked because of the increased “dental IQ” of adult patients regarding today's clear aligner systems. Additionally, the marketing investment made by the manufacturers of today's clear aligner systems (Align Technology, AOA Pro, and formerly Ortho Clear) has dramatically changed the average adult's perception of orthodontic treatment.
Prior to the development of the current Clear Polymer Aligner Systems, traditional fixed orthodontic appliances were the best options for even the most minor of orthodontic treatment needs. For a variety of reasons, wearing fixed orthodontic appliances may simply not be an option for many adults today. The concerns range from hygiene related issues and comfort to esthetics for those in the workforce. Now orthodontists and general dentists have options to offer patients that allow treatment of their malocclusion while simultaneously satisfying their esthetic demands during treatment.
The concept of using clear aligners to gradually move and position teeth was first put into practice in the mid 20th century. Since that time the major advancements with this method of tooth movement have been in the materials the aligners are made of, the process by which the aligners are made, and the technology used to virtually plan the desired tooth movement. While early models allowed only treatment of modest malocclusions, current aligner systems are being used in the treatment of progressively more severe malocclusions as the understanding of how to effectively use these systems expands.
Perhaps the most intriguing aspect of the technology developed by the aligner companies is the treatment planning software. Invisalign, for example, utilizes virtual treatment planning models to assist the doctor in finalizing a treatment plan. For the doctor and patient alike this presents an opportunity to view and critically review the planned tooth movement and progress at any stage of treatment prior to initiating care. I find patients especially appreciate reviewing their virtual result as it gives them a visualization of what their individualized treatment outcome will be.
The process of aligner fabrication is initiated with a standard set of orthodontic records to begin initial treatment planning and establishing the individualized goals of orthodontic treatment for the patient. After carefully examining the mechanics needed to achieve the desired tooth movement, the orthodontist or general dentist will have a concise read as to whether traditional fixed appliances or an aligner system are an appropriate means to provide treatment and achieve the desired results.
A Vinyl Polysiloxane Impression Material is then used to capture the patient's maxillary and mandibular arches and sent along with an occlusal registration and complete set of treatment planning records for scanning. It is critical the orthodontist or general dentist provide clear, concise, and precise instructions as to the desired tooth movement, instructions for interproximal reduction (IPR, enamel stripping), bonded attachments to be used, and any other instructions relevant to the treatment plan.
A computed tomography (CAT) scan is then made of the PVS impressions to create the precise three-dimensional virtual models of the maxillary and mandibular arches. Following the instructions provided by the orthodontist or general dentist, technicians begin align the dentition in a series of steps which corresponds to the number of aligners needed for case completion. The orthodontist or general dentist must then carefully examine the virtually treated case result as well as the individualized tooth movements achieved on the computer screen. This step is critical and is where the doctor’s knowledge of what is reasonable from a biological and clinical standpoint comes into play. Simply stated, movements of individualized teeth or segments of the dentition need to be carefully planned by the doctor so that what is achieved on the computer screen may be achieved clinically. Foregoing this careful review may lead to needless revisions in treatment, prolonged treatment, increased cost to the care provider, and unsatisfactory end results.
Once the case has be thoroughly reviewed and accepted the aligners are fabricated using each individual company’s proprietary software and delivered to the patient within weeks.
The demand for clear aligner options is continuing to grow dramatically especially among the adult patient population. This technology has opened doors to treatment for patients who otherwise may not have pursued orthodontic care. As this demand grows, it will continue to drive the improvements in software and materials and prompt doctors to find solutions to current perceived limitations to these appliances.