Inadequacy of mandibular anchorage—Five years later

Abstract

With some slight changes, I can only repeat my former statements on this subject. If a case requires mandibular anchorage, the orthodontist should plan deliberately to protect that anchorage in the best way available for that particular case. In this worthy endeavor, the following suggestions are offered: 1. 1. When deciduous teeth are present in the mandibular arch, little or no Class II elastic pressure should be used. In treatment, extraoral anchorage should be considered. 2. 2. In most mandibular anchorage situations, one should plan to use every available precautionary measure to prevent disturbance of resistance units, including extraoral anchorage (at least as a supplementary technique). The various types of mechanics should be considered, and the one which seems most suitable to the case at hand should be chosen. The lingual, labiolingual, edgewise, Johnson, Universal, or Crozat man should not hesitate to step across an imaginary boundary and use the mandibular appliance which common sense dictates is best for the case he is treating. Sectional treatment in the maxillary arch can result in lighter stress on mandibular anchorage, and that stress exists for a shorter time. Directing major tooth movement through cancellous bone channels, rather than against compact areas, should also reduce stress requirements. One should plan to move only those teeth that must be moved. Normal shift of individual teeth may be expected following the development of space provided by movement of other teeth or following the removal of interference. 3. 3. In selected cases, mandibular anchorage hazards should be reduced by extraction of maxillary second molars or maxillary first premolars. 4. 4. During retention, one should continue to observe tendencies for disturbance in the mandibular arch, whether they are due to treatment or to natural causes. Probably most cases should have equilibration by either the qualified orthodontist, a qualified general dentist, or a periodontist. One should note particularly whether the mesiolingual inclined plane of the maxillary canine is striking the distobuccal inclined plane of the mandibular canine, either in occlusion or in excursions of the mandible. This might cause mesial tipping of mandibular canines and crowding of mandibular incisors. If it is impossible to prevent considerable crowding by any available means, it may be desirable, under the conditions previously mentioned, to extract one lower incisor. Stripping might alleviate slight discrepancies. 5. 5. The various steps in treatment should be timed, if possible, in relation to new growth studies. Since mandibular growth usually picks up at puberty, elastic therapy may be used if necessary, in Class II cases during this stage of growth. It is wise to time for a younger age in girls than in boys, for growth in boys is not only later but more prolonged. As our knowledge of the growth of the denture and the face gradually increases, we probably will pay more attention to circumventing the abnormal and aiding and abetting the normal than to mechanical devices. Indeed, some are already “guiding growth,” as it were, with the perhaps more knowledgeable use of the simple appliances of yesteryear, notably such devices as bite plates and cervical gear. 6. 6. I must add a compelling additional thought. In 1955 I quoted the late Charles Waldo's 36 paper, entitled “A Practical Approach to the Problem of Orthodontics.” Since then, Wilson 37 has added the paper that he read at the 1959 Golden Anniversary Luncheon of the American Association of Orthodontists in Detroit. Both of these papers should be read and reread. They stress the real responsibility of orthodontics. What has this to do with mandibular anchorage? Nothing directly, but the ideas expressed in these two papers are intimately connected with anything that we might do or hope to do in orthodontics.