end up with OSA later in life. Because known sequelae ofOSA include hypertension, stroke, and possible early death,the decision to close these spaces might well have ominousconsequences.

I have seen very nice increases in the PAS (and elimina-tion of OSA symptoms) in adults as I have reopened missinglateral spaces that had been orthodontically closed in adoles-cence. Some might feel that I am an alarmist and carrying thediscussion to a ridiculous extreme. To those orthodontists, Isuggest that they reexamine all patients they have treated withspace closure to screen for these issues. Comparing PASpretreatment, posttreatment, and 20 years later might providea rude awakening for those who still like to close the spaces.Taking a thorough medical history with particular emphasison snoring and OSA symptoms would be essential. The resultmight be a bit surprising or disconcerting, and perhaps eveninduce a feeling of guilt.

When we apply the concern about a decreased PAScontributing to OSA, then the position of the chin becomesimportant as well. Because the tongue is attached to the chin,anything that keeps the chin from growing to its geneticallyideal forward position might decrease the PAS and increasethe chance for OSA. Combining the change of mandibulargrowth direction from forward to vertical as noted above andthe decreased tongue space from collapsing the maxillaryarch, there might be a double assault on the PAS with missinglateral space closure. Either situation alone is a cause forconcern. Considered together, closing lateral incisor spacesmight well be treatment that cannot be justified under anycircumstance.

Is it in the realm of possibility that the seeminglyinnocuous decision to close missing lateral incisor spacesmight escalate into life-threatening sequelae of OSA?

Stranger things have been proven in the past. Further researchon these issues is obviously needed.

In the past, closing the lateral spaces was driven by the“ I’ ll save your child from a bridge” thought process. Thatgave way to the “ I’ ll save your child from an implant”mentality, which often still drives the decision to closemissing lateral spaces. Some day, our specialty might bedriven by the “ I’ ll save your child’s life and facial appearanceby insisting that we open the missing lateral incisor space foran implant or a bridge” mentality.

It seems to me that the orthodontic specialty shouldexpand the discussion on this topic far beyond the few pointswe traditionally deal with. I hope this letter is as an impetusfor orthodontists to rethink their treatment philosophies onthis very important matter. If they examine their treatmentresults carefully, I suspect that few will find reasons to closesuch missing lateral incisor spaces in the future.

William M. Hang, DDS, MSDWestlake Village, Calif

0889-5406/$30.00doi:10.1016/j.ajodo.2004.04.009

Editors’ responseI appreciate the time and thought that have gone into this

letter. Avoiding space closure in a patient with missinglaterals might not save a life, but the practice certainlyjustifies more research to evaluate the resulting estheticimpact, not to mention the potential for obstructive sleepapnea. Perhaps other readers believe as you do, but we reallyneed to see the evidence.

David L. Turpin0889-5406/$30.00doi:10.1016/j.ajodo.2004.04.010

American Journal of Orthodontics and Dentofacial OrthopedicsVolume 125, Number 6

Readers’ forum 19A