Great Expectations
I still vividly remember my reaction upon approaching my general dental practice and seeing a certain unappointed denture patient waiting for the door to open. Beginning the day by being pleasant to a perpetual malcontent was more than my fragile psyche could handle, so I would drive past the office and wander the streets of our small town until I was sure my assistants had arrived and greeted my nemesis. I would eventually see the faultfinding grump, of course, but at least it didn't have to be my first duty of the day.
After reading the articles on orthodontic retention by Edwards and Little et al. in the May 1988 AJO, I began to wonder whether retention patients might turn out to be an even greater nemesis than those people who never understood that dentures were not substitutes for teeth, but only for no teeth.
Studying the effects of circumferential supracrestal fiberotomy on post-treatment relapse, Edwards discovered that CSF patients showed only 14% relapse for the first two to three years, vs. 43% relapse for the control group. But that difference narrowed considerably in 12 to 14 years after treatment--35% for the CSF group vs. 54% for the controls.
The study by Little et al. was even less sanguine. None of the patients in this study had had fiberotomies--which is probably more like most of our practices--and after 20 years, only 10% of these former orthodontic patients had what the authors considered acceptable alignment of mandibular teeth.
Although the degree of relapse is regrettable, the truly alarming feature of these studies is that the patients were treated by university-trained, board-qualified, top-of-the-line professionals. If 90% of their well-treated patients relapsed badly, what hope is there for the rest of us?
More light was shed on post-treatment changes by Behrents, who re-evaluated 168 of the original Bolton patients from the late '20s and early '30s (see the interview in the December 1986 JCO). Behrents found that people never stop growing or changing, and that if a patient had an orthodontically unfavorable growth pattern at age 12, that pattern still expressed itself 40 years later. He concluded that orthodontists are naive to expect a two-to-three-year treatment interlude to countermand a patient's genetic code and neuronal reflexes.
Orthodontists, it seems, would be well advised to spend more time counseling patients and parents about the inevitable posttreatment changes. Better they should expect too little than too much. And as Edwards observed, not all of the changes are true relapses; teeth in his study often moved in completely different directions from their original positions. Unfortunately, neither orthodontists nor patients seem to appreciate this distinction. Both see changes and assume they somehow are the orthodontist's responsibility. But are they? Accumulating evidence indicates otherwise. Still, more and more of our patients and their parents expect us to take on that awesome and practically impossible responsibility of guaranteeing lifetime results.
If our practices are to be consumer-driven, then we must respond to the challenge. But even if we tried to retain patients forever, we would still be limited by patients' compliance with removable retainers, or the long-term dependability of materials currently used for lingual fixed retainers. Practically speaking, there are a few things we can do to limit post-treatment relapse:
Twenty-two years ago Dr. Tom Matthews, a clinical professor at Baylor University, told me he would happily treat patients for half his usual fee if he didn't have to worry about the retention period. I didn't believe him at the time, but of course he was absolutely correct. There is more professional grief and misunderstanding associated with this phase of treatment than with any other. The retention period is important to patients. We need to become better at shaping their expectations, as well as more technically proficient at retaining them, if we are to escape the wrath of Nemesis--the Greek goddess of retribution.