Some instant remedies are good cosmetic dentistry, but other procedures are somewhat suspect.
WRITTEN BY Marita K. Janzen, DDS, MS
General dentistry is not what it used to be. The days of simply drilling and filling teeth for the health of the dentition are long gone. With television shows such as “Extreme Makeover,” “Dr. 90210,” “Ten Years Younger,” and “What Not to Wear,” many adults and teenagers are seeking ways to look better in the shortest time possible with minimal effort. Oftentimes, these shows focus on what can be done with “cosmetic” dentistry in an hour or two, then show a vastly improved dental appearance. Some of these instant remedies are good cosmetic dentistry, but some procedures are somewhat suspect. The application of veneers and composite to malaligned anterior teeth to make them appear straight is often fraught with negative periodontal and occlusal implications. Bulky restorations may initially look good, but marginal gingivitis and possibly even periodontitis is sure to set in, even with the most proficient of tooth brushers. Because the posterior occlusion is not even addressed, we don’t get to see makeover recipients a few years later, and we’ll never know whether improvements built on shaky platforms lasted.
For general dentists to create esthetically pleasing smiles with optimal function of the teeth, sometimes orthodontic alignment of the teeth is beneficial. Dentists refer patients to orthodontists for evaluation, and patients declare that there is no way they are going to wear a mouth full of metal. What can we do other than braces?
In the past, when minor movement of the teeth was required, patients were not interested in conventional braces, and some alignment of the teeth was desired, various orthodontic removable appliances improved the position of the teeth. Hawley-type retainers with springs, spring aligners, or positioners may have been used. Drawbacks to these appliances were that the teeth could only be tipped or rotated. Ideal torque control, incisal edge alignment, and good axial inclination were difficult to achieve. These appliances also were somewhat cumbersome for patients — and, heaven forbid, visible.
Orthodontists have many techniques available to correct malocclusion and improve the alignment of the teeth. The past few years have seen the advent of a new orthodontic technique using a series of plastic aligners to correct a malocclusion. At present, two companies offer this technique as a comprehensive treatment alternative, namely Invisalign® and OrthoClearTM. Rather than using conventional braces, custom-made aligners that fit over the teeth are used to apply pressure to the teeth to move them in the desired direction.
The biological response of the teeth is the same regardless of the appliance chosen to move them. As an orthodontist, I formulate a treatment plan and make treatment goals for each patient. I offer fixed appliances, other orthodontic appliances, Invisalign, or OrthoClear, and give the risks and benefits for each and the alternatives. There are cases that I would rather treat with fixed appliances, and there are problems for which treatment with aligners is the better option. Patients can make informed final decisions.
WHAT CAN WE DO OTHER THAN BRACES? For general dentists to create esthetically pleasing smiles with optimal function of the teeth, sometimes orthodontic alignment of the teeth is beneficial. Dentists refer patients to orthodontists for evaluation, and patients declare that there is no way that they are going to wear a mouth full of metal.
The obvious reasons for patients to choose Invisalign or OrthoClear are esthetic and oral-hygiene concerns. The aligners and composite attachments that are often needed to aid in movement of the teeth and retention of the aligners are virtually invisible. Because the aligners are removable, patients are able to brush normally and floss their teeth without having to use floss threaders.
The first prerequisite for patients to choose Invisalign or OrthoClear is that a fully mature adult dentition is present with the second molars in place. Both aligner techniques involve sophisticated software in order to fabricate the aligners, however, technology cannot adequately predict the shape and position of the teeth as they erupt. It is difficult to aim at a moving target. As for treating adolescents, it is easier to correct a malocclusion with traditional braces while the teeth are in transition and the patient is maturing and growing with knowledge that at the end of treatment the full complement of teeth will be present.
In my experience, the most rewarding cases are generally Class I malocclusions with mild to moderate crowding of the incisors, cases with generalized spacing, and those with one or two teeth in crossbite. Generally, in cases with mild to moderate crowding, slight expansion can be achieved with the aligners to relieve the crowding, and sometimes interproximal reduction needs to be performed so teeth can move more easily past the contact points. If the upper arch is extremely narrow, I often expand first with a Hawley-type expander because the force delivered with the aligners for expansion is sometimes insufficient. Patients with spacing of the anterior teeth work nicely, especially because these patients often have small teeth or lateral incisors. Aligners allow for proper positioning of the incisors for future veneers, restorations, or retracting the teeth to close the spaces.
As for correcting crossbites, the thickness of the aligners between the posterior teeth allows for disclusion of the anterior teeth, making crossbite correction relatively simple.
CLEAR OR TRADITIONAL? For Invisalign or OrthoClear, a fully mature, adult dentition must be present. If extractions are indicated, it is easier and quicker to get proper root angulation and torque to adjacent teeth with conventional braces.
Some orthodontists are comfortable treating extraction cases with Invisalign or OrthoClear. I find extraction cases frustrating. In cases where premolar extraction is indicated, the closure of the extraction sites progresses too slowly for me. The rate of bone resorption in the extraction site outpaces the time it takes to close the extraction site, making complete closure of the extraction site difficult. In cases where lower incisor extraction is indicated, the extraction site is often visible. I have tried to place small pontics or some composite in the aligner to fill in the extraction site. The pontics are difficult to keep in place in the aligner because they must be removable so that at each stage of the aligners the pontic size can be reduced to accommodate the closure of the extraction site. Because the pontic is somewhat mobile and the patient is aware of its presence, it becomes difficult for the patient to deal with. It is also difficult to get proper root angulation and torque to the adjacent teeth. I close extraction sites with braces. Class II Division II patients often have deep bites. To help open the bite, treat the lower arch with conventional braces and the upper arch with Invisalign or OrthoClear.
The position of the labial surface of the canines makes the esthetic transition of the anterior to the posterior teeth. Because of their conical shape, severely rotated canines are difficult to correct — even with attachments on the canines with aligners. The blade shape of the incisors, however, makes the correction of rotations of incisors work well.
My most pleasant surprise has been the results with anterior open bites. Because of the thickness of the aligners, there is intrusion of the posterior teeth that cause a decrease in the mandibular plane angle and, therefore, decrease the anterior open bite. Conversely, in deep-bite cases, it is difficult to open the bite. Leveling the curve of Spee is difficult with thick aligners, and intrusion of the incisors has not worked well for me. Class II Division II patients often have deep bites, and because I find it difficult to open the bite, I treat the lower arch with conventional braces and the upper arch with Invisalign or OrthoClear.
When everyone is looking to improve his or her appearance, alignment of the teeth to achieve a nice, white smile can be beneficial. Alignment of the teeth can be done with braces, but there is definitely a place for using clear aligners.