the Levin and D’Amico article on high muscle attachmentwas not referenced.

Robert L. Vanarsdall, DDSPhiladelphia, Pa

0889-5406/$30.00doi:10.1016/j.ajodo.2004.04.006

Editor’s responseI must admit that I was surprised to receive this response

to the republication of a classic article that has influenced mytreatment of patients for the past 25 years. Taking youradvice, I looked back to April 1974 and found the article byLevin and D’Amico entitled “Flap design in exposing une-rupted teeth.” The authors point out that a high muscleattachment is an etiologic factor in delayed eruption of someteeth and describe a surgical procedure for exposing theaffected tooth to encourage eruption. Four intraoral photo-graphs show the use of this flap technique in treating anorthodontic patient. No final records are shown, and there isno long-term evaluation of the patient. The authors accuratelynote in summary, “There is no justification for the inadvertentremoval of attached gingiva to induce eruption because of thefuture problems that are created. Conservation of attachedgingiva is a major consideration when any surgical procedureis performed in the oral cavity.”

David L. Turpin0889-5406/$30.00doi:10.1016/j.ajodo.2004.04.005

Treatment of missing lateral incisorsThe editorial in the February issue (Turpin DL. Treatment

of missing lateral incisors. Am J Orthod Dentofacial Orthop2004;125:129) provided a very interesting overview of asubject that still befuddles the profession. It provides insightinto some esthetic issues, but certainly not all of the estheticand functional issues that should be addressed. Like mostarticles written on this subject, it focuses on dental estheticsand mentions making decisions based on the existing skeletalpattern. Nowhere in the literature does anyone suggest thatclosing the lateral incisor spaces might actually redirect thegrowth of the lower jaw and change the skeletal pattern. Nordoes the literature deal with the serious functional issues thatcan result from such a change in growth pattern. Based on myexperience, I think this can happen, does happen frequently,and has serious consequences that we can no longer afford toignore.

There is no better example to support my concern thanthis article (Biggerstaff RH. The orthodontic management ofcongenitally absent maxillary lateral incisors and secondpremolars: a case report. Am J Orthod Dentofacial Orthop1992;102:537-46). It is a case study of a patient with missinglateral incisors that purported to show a successful treatmentwith space closure. After considering the x-ray tracings, Iconcluded that the treatment for this patient was far from asuccess and was actually a disaster waiting to happen. Duringa phase 1 treatment with expansion of the maxilla, the

patient’s face grew ideally downward and forward, as onewould expect, confirmed by the ceph tracings from ages 8 to12. Before phase 2 treatment, the patient had approximately 4mm of space on each side for the lateral incisors, which couldeasily have been opened to 6-7 mm for an implant. Instead ofopening the spaces for a bridge or an implant, they wereclosed with phase 2 treatment from ages 12 to 14. The 2lateral head x-ray tracings from these ages show cessation offurther forward growth and conversion to only verticalgrowth of the mandible as the spaces were closed. The patientdid not appear to be an early maturer and probably hadsubstantial vertical growth significantly affecting facial bal-ance after the treatment.

The tracings clearly show substantial retraction of themaxillary central incisors as one would expect, consideringanchorage of 2 upper central incisors pitted against the entiremaxillary arch. The idea that many orthodontists present ofbringing the canines forward into the lateral space is a myth.Anchorage considerations alone would dictate that the cen-trals would be retracted more than the entire buccal segmentof teeth would be advanced unless a facemask or similarappliance was used. Do I believe that this retraction causedthe lower jaw to stop growing forward and redirect to verticalgrowth? Absolutely, but what I believe matters only as ittranslates into treatment for my patients.

Many would suggest that the change in this patient’sgrowth pattern from downward and forward to just downwardis genetically controlled and thereby unpredictable. Somemight suggest that this is only one example and is not seen inother cases. They might conclude that this change is unrelatedto the treatment and just a coincidence. Looking at my owncases and those in the literature over the past 20 years leadsme to strongly disagree. I would challenge every member ofthe AAO to accurately trace out every similar case each hastreated with space closure to follow the growth direction ofthe lower face after space closure. My experience is that thegrowth direction of the lower face can be permanently andunalterably affected in such cases. Aside from esthetic con-siderations of having a weaker chin, the sad fact is that thiscan have serious functional consequences as noted below.

If you believe that the teeth are in some type of balancewith the cheeks, lips, and tongue, it becomes interesting tospeculate on what such space closure does to the tonguespace. The interest in treatment of obstructive sleep apnea(OSA) in the dental and orthodontic professions in the lastfew years makes the discussion even more relevant. Theposterior airway space (PAS), or distance between the back ofthe tongue and the back of the throat, is a critical measure-ment in people who have OSA. Anything that decreases thetongue space might be expected to drive the tongue distally;this can cause apnea during sleep. I am unaware of any studythat shows that patients with missing lateral incisors alsosomehow inherit smaller tongues. Assuming that the tonguesize is independent of the missing laterals, one might expectthe tongue to be crowded as the spaces are closed, and thePAS would often decrease. My experience would lead me tobelieve that this happens frequently, and many such patients

American Journal of Orthodontics and Dentofacial OrthopedicsJune 2004

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