LETTERS TO THE EDITOR Neurotoxic causation of paresthesia

lapse, it would be helpful if the samples were separated along these lines, and both groups were considered individually. Thank you. Jack Einhorn, DDS Brooklyn, N.Y.

To the Editor:

I recently published an article demonstrating the neurotoxic causation of paresthesia for the first time. Oral surgeons have been heavily litigated regarding this subject, and it appears it was an unexpected neurotoxicity of local anesthetic metabolites. A recent 2-year study has reduced the complication by 87% in my practice by changing the local anesthetic usage. I hope you can share this information with your orthodontic colleagues because (1) they may experience paresthesia complications with patients referred to oral surgeons and (2) paresthesia is not a matter for litigation and is a classic case of overrationalization without substance, resulting in many hurt professionals and their pocketbooks. I hope this scenario does not develop in your field of orthodontics. Alfred A. Nickel, DDS, MS Danville, CA 94526

Recommendation for postretention study To the Editor:

The University of Washington group is to be commended for their rigorously designed and objective research, conducted over the years, regarding postorthodontic relapse of lower anterior crowding. (Mandibular Arch Length During the Mixed Dentition. Little, Riedel, and Stein, [AM J ORTHOO DENTOFAC ORTHOP 1990;97:393-404]). The only objection that could be raised is that the samples studied have all been treated by graduates or associates of the orthodontic program of the University of Washington (or so I assume) and that they may have a specific treatment bias. In their findings, they do not differentiate between patients who have been treated with fixed as opposed to functional appliances. The believers in functional treatment have long claimed greater stability with their long-term archgaining efforts as opposed to fixed treatment. I therefore propose an objective 10-year postretention study, along the guidelines of the University of Washington group's studies, to be carried out on the patients of such eminent, functionally oriented clinicians as Drs. Rolf Fr&nkel and Norman Cetlin. With these patient pools, any question of the incorrect use of their appliances and theories should be factored out. In addition, since there is a belief that deep bite, low mandibular plane angle Class II, Division 1 and Class II, Division 2 cases do not behave as other malocclusions do when it comes to posttreatment lower anterior re-

Orthodontics and TMJ disorders To the Editor:

I am compelled to respond to Dr. Reynders "Review of the Literature" article entitled "Orthodontics and Temporomandibular Joint Disorders" that appeared in the June 1990 issue of the AM J ORTHODDENTOFACORTHOP. It is unfortunate that the profession continues to be burdened with material of this nature under the guise of serious scientific investigation. The author has conducted a study with a thinly veiled, predetermined conclusion involving four interrelated objectives: 1. To substantiate the denial of any relationship between temporomandibular joint disorders and dental malocclusion. 2. To attempt to dissociate orthodontic treatment, in general, from having a causal relationship to TMJ disorders. 3. To exonerate the traditionally oriented orthodontic community employing fixed appliances and retraction therapy from the charges of iatrogenically creating TMJ disorders. 4. To discredit authors whose writings and clinical experiences claim (a) a strong relation between TMJ disorders and dental malocclusion, (b) stable orthodontic results with enhanced facial and dental cosmetics and no untoward TMJ by-products resulting from their treatments, (c) routine success in the elimination of TMJ disorders by means of their "physiologic" approach to treatment, and (d) that the extraction of teeth and retractive orthodontic methods commonly employed in the treatment of dental malocclusion are primary causes of TMJ disorders. Dr. Reynders, a former research associate and clinical instructor in the Department of Orthodontics of Northwestern University, has divided 91 publications from 1966 through 1988 that are concerned with the relationship of orthodontics to temporomandibular joint disorders into three basic categories--viewpoint publications, case reports, and sample studies. Of the 91 publications, 55 are classified as viewpoint publications, a group that is discounted by the author as being unworthy of serious consideration, essentially because of an alleged lack of controls. I believe it is no accident that most of the viewpoint group is comprised of authors who hold conventional treatment to be re21A

22A

Letters to the editor

sponsible for inciting TMJ disorders and who also claim success in eliminating these problems by means of their philosophy of treatment. Among the 55 viewpoint publications is an article by this writer entitled "Clinical Implications of Mandibular Repositioning and the Concept of an Alterable Centric Relation." Another article that was omitted totally was "Physiologic Response to Dental Malocclusion and Misplaced Mandibular Posture: The Keys to Temporomandibular Joint and Associated Neuromuscular Disorders," by Levy in Basal Facts, The International Journal of Biologic Stress and Disease, 1981. The second group characterized by Dr. Reynders as case reports comprises 30 publications. Case reports generally fare about as poorly as the viewpoint publications for a variety of stated reasons. It is interesting to note that "23 of the 30 case reports conclude that orthodontic treatment can have a curing effect on temporomandibular disorders." Dr. Reynders does not discuss what manner of orthodontics claims responsibility for the reported cures. Sample studies comprise the third group of publications. There are only six sample studies cited, two of which are essentially repeats of each other by the same main author, C. Sadowsky in 1980 and 1984, respectively. The sample study group clearly enjoys Dr. Reynders' favor, although two of the six authors who found that orthodontics can cure TM disorders were suspect in Dr. Reynders' view. The author's personal bias, overall purpose, and frustration, evident throughout the publication, is neatly summed up in his conclusion: "it is surprising that, although some of these carefully designed sample studies were published in the early 1980s, the authors of viewpoint publications and case reports have largely ignored these findings and have continued to saturate the literature with their biased data." Contrary to Dr. Reynders' charge of ignoring his sample studies, a primary purpose of this response is to address directly two of the six studies this writer is familiar with, the Sadowsky and Begote report (AM J OBTHOD 1980) and the Sadowsky and Poison report (AM J ORTHOD1984). AS previously indicated, the two articles are essentially a repeat of the same theme. Two groups of patients were observed and evaluated for signs and symptoms of TMJ disorders over a period of time. One group of patients displaying dental malocclusion ("abnormal maxillomandibular relationships as well as malaligned teeth") were treated by means of conventional fixed appliance orthodontics ("retraction and/or extractions"). A roughly equal number of patients also displaying dental malocclusion were not treated and served as the control. The prevalence of TMJ signs and symptoms of the two groups were subsequently compared and found to be more or less equal. Dr. Sadowsky's conclusion therefore was that no relationship existed between those patients orthodonticaIly treated for the "correction" of their dental malocclusion and those who

Am. J. Orthod. Dentofac. Orthop. January 1991

were untreated. These studies were intended to exonerate the orthodontic community employing conventional orthodontic treatment from the charges of having iatrogenically incited TMJ disorders as a consequence of their treatment. The conclusions reached in the Sadowsky studies are important indeed, but for a different reason than that intended by their authors or cited by Dr. Reynders and others. They establish not an exoneration, but an indictment of the "fixed-mandible school of orthodontics" that has concerned itself primarily with the alignment of teeth while perpetualizing maxillomandibular mismatches by masking procedures involving tooth extraction and surgery (Class III surgery excepted). The Sadowsky treatment results reflect a cosmetically enhanced but continued dental malocclusion (unaltered maxillomandibular relation) and physiologic insult that have merely been masked and are thus worthless as an objective measure of TMJ treatment or cause, except in a negative sense. Dr. Sadowsky's treatment experience differs totally from that of dentofacial orthopedists who are able to identify TMJ causality and routinely eliminate symptoms by improving the neuromuscular/skeletal system relationship while providing dental and facial cosmetics, simultaneously. Dentofacial orthopedists rendering these services frequently have the opportunity to demonstrate the relationship between malpositioned jaws (dental malocclusion) and TMJ disorders by changing the mandibular posture, thereby inducing or eliminating symptoms of a TMJ disorder virtually at will. A physiologic curative potential is available to the function-oriented orthodontist (dentofacial orthopedist) that has nothing to do with the issue of fixed or removable appliances. The orthodontist's unique opportunity and ability to correct maxillomandibutar mismatches, and by extension the associated muscles and temporomandibular articulation, becomes routinely feasible by proper tooth movement and the reshaping of the dental arches in a conducive manner that intimately involves the patient's occlusal proprioception. The issue is not whether fixed or removable appliances are employed (an unrelated and unimportant point belabored by Dr. Reynders); it is whether the entire stomatognathic system consisting of teeth, jaws, associated muscles and ligaments, and the TMJ articulation is considered in rendering care. Orthodontic treatment does not cause or cure TMJ disorders. Orthodontic treatment does, however, have the potential to do either, predicated on whether the treatment enhances physiologic homeostasis or produces physiologic insult. A crucial aspect of treating many dental malocclusions requires the corrective physiologic realignment not just of the teeth but of the mandible as well. My experience concerning the intimate relationship of dental malocclusion and TMJ disorders spans more than 25 years and involves the treatment of hundreds of orthodontic/TMJ cases, most of which are fully documented,

Volume 99 Number 1

stable, and free of symptoms. As with the work of many others who employ physiologic as opposed to mechanistic concepts in their treatment, the questions raised in this review have long since been settled. Successful treatment requires that we follow the anatomic requirements of our patients; conventional orthodontics mandates that treatment structure the patient's dentition to conform to arbitrary manmade standards, often at the expense of the TMJ and associated neuromusculature. It is ironic, but predictable, that the void created by the orthodontists' abdication and denial of his role and responsibility in TMJ disorders would be filled by others less equipped. At the present time most treatment is directed to palliative symptom removal. Patients who have this affliction and are treated by other than a function-oriented orthodontist can at best expect a lifetime of pain management rather than cure. The basic sciences have long since discredited the fixed-jaw hypothesis in all areas of dentistry (e.g., P.H. Levy, guest editor "An Alterable Centric Relation in Dentistry") Dental Clinics of North America, July 1975.) The real question of Dr. Reynders is "How much longer can those who control the dental school curriculum and the major professional publications suppress the truth in a rising tide and awareness of iatrogenic disease?" Philip H. Levy, DDS 1359 Bellmore Ave. North Bellmore, NY 11710

Reply To the Editor:

Thank you for the opportunity to respond to Dr. kevy's viewpoint on the relationship between orthodontics and temporomandibular disorders. There is always some degree of tension between the beliefs and practice of the clinician and the findings from scientific studies. Therefore it is not surprising when a clinician feels angry toward both the message and the messenger of a published study. However, despite the charges of bias and preconceived results, my study was not done to prove any specific point. Rather, it was an attempt to classify the available literature on this topic according to the methods underlying each paper. I stand by the major conclusion that was drawn from my findings, namely, the few well-controlled studies done so far have shown little or no relationship between orthodontics and temporomandibular disorders, while the majority of viewpoint publications and case reports have presented an opposing view.

Letters to the editor

23A

One of the characteristics of a good and thoughtful clinician is the willingness to abandon old myths and incorporate new information into his practice. I hope Dr. Levy will be able to reconsider his personal viewpoint, as well as the findings from the well-designed sample studies cited in my paper, before he reaches any final conclusions. Reint M. Reynders, DDS, MSc Via M. Bandello 2 20123 Milan Italy

Ceramic brackets tested in study no longer in circulation To the Editor:

I would like to address the readers of your JOURNAL in reference to the article entitled "Bond Strength of Ceramic Brackets Under Shear Stress: An In Vitro Report" by A.D. Viazis, G. Cavanaugh, and R.R. Bevis (AM J ORTHOD DENTOFAC ORTHOP 1990;98:214-21). It should be noted and clearly emphasized that the Transcend (Unitek/3M) and Gem (Ormco Corp.) ceramic brackets tested in this study 2 years ago are no longer in circulation; therefore clinicians should not confuse the appliances presented in the article with the new generation of brackets that these companies are introducing to the orthodontists. Current investigation is under way to assess the clinical application of the new brackets. Caution would be justified if clinicians are using the old brackets. It is wise to be critical of every new material. Thorough, in-depth investigation is absolutely necessary to assess the biocompatibility of all materials. Comprehensive research endeavors initiated at the dental schools, academic institutions, and research laboratories of various companies provide a sound, solid, critical, and nonbiased evaluation of the performance of all innovative ideas. It is crucial, for the good of the profession, our patients, the quality of our work, and our commitment to excellence that we constantly search for new and better modes of treatment. We have certainly come a long way from the time we banded every single tooth. Good research has kept us on the path of constant knowledge. As the great Greek philosopher of the ancient world once said: "No one will be able to learn a thing if he is convinced he already knows it" (Socrates). Anthony D. Viazis, DDS, MS Assistant Professor Orthodontic Department Bto'lor College of Dentistry

Orthodontics and TMJ disorders.

LETTERS TO THE EDITOR Neurotoxic causation of paresthesia lapse, it would be helpful if the samples were separated along these lines, and both groups...
305KB Sizes 0 Downloads 0 Views