A. Yaffe, D.l&D.,*
overlap: N. kochman,
and J. Ehrlich
School of Dental Medicine, Jerusalem, Israel
Severe vertical overlap may predispose the patient to abnormal function, improper mastication, excessive stress, and functional problems such as bruxing, clenching, and craniomandibular disorders. This report describes the establishment of a new occlusal relationship by using the potential of posterior tooth eruption with the Hawley bite plane or the canine platform method. It was used in patients with a full complement of teeth or with some missing teeth. Patients treated by either the Hawley bite plane or the canine platform demonstrate a stable and long-lasting new occlusal relationship. The method described is efficient, inexpensive, and convenient to the patient. (J PROSTRET DENT 1989;62:638-41.)
eep bite” or “closed bite” (severe vertical overlap) is characterized by increased vertical difference between the incisal edges of the opposing central incisors when the mandible is brought into habitual or centric occlusion.‘y2 It is believed that the condition predisposes the patient to abnormal function, improper mastication, excessive stress, and functional problems such as bruxing, clenching, and craniomandibular disorders.3, 4 The treatment sequence of chiidren is well accepted.3p5However, the treatment of adults presents many difficulties. In young patients severe vertical overlap is treated orthodontically, not always satisfactorily. In adults it can aggravate periodontal problems by the impingement of oppositig teeth on soft tissue both on the lingual aspect of upper teeth and on the facial aspect of the mandibular teeth (Fig?. 1 and 2), as well as excessive anterior wear. This investigation was partially supported by The Morton Amsterdam Perio-Prosthesis Chair. *Se&or Lecturer, Department of Oral Rehabilitation. **Associate Professor, Department of Oral Rehabilitation. 10/l/14495
Such wear causes chipping of enamel, complicating existing esthetic problems and, in some instances, adversely affects temporomandibular joint function.4p 6 Vertical overlap can be aggravated by the loss of posterior teeth and periodontal support. Clenching may be a contributory factor.7 Crowding and close root proximity are sometimes also found in the anterior region3 Faulty treatment often complicates the condition. Treatment in adult patients can be either radical or conservative.7 Conservative treatment is comprised of three approaches: (1) restorative, (2) orthodontic, or (3) combined orthodontic and restorative.7 In restorative treatment, the objective is to increase the vertical dimension of occlusion by a fixed or removable prosthesis to relieve the anterior region (Figs. 3 and 4). This mode of treatment only temporarily relieves the anterior region because changes may occur by intrusion of posterior teeth (Fig. 5), eruption of anterior teeth, change in mandibular position, or a combination of all three. Another approach involves intruding and realigning the upper anterior teeth orthodontically.3* 5y8 This mode of treatment should be used only for patients with a healthy
Fig. “‘1. Impingement of maxillary incisors iii soft tissue.
Fig. 2. Impingement of mandibular incisors on palate.
3. Metal overlaid occlusal splint.
5. Same patient as in Fig. 4, demonstrating posterior open occlusion caused by intrusion. Arrow points to tissue impingement.
4. Acrylic resin occlusal splint in place. Fig.
periodontal condition.g Shortening of the anterior teeth may also be effective, but this treatment brings only temporary relief because the original relationship often returns.7 This article describes a new way of treating severe vertical overlap. The objective is to use the potential of posterior tooth eruption by either Hawley bite plane therapy or the canine platform method.lO Adjunctive orthodontic treatment is sometimes incorporated.
Treatment should be attempted only for patients with a full complement of teeth or with a minimal number of teeth missing on either side. Before treatment all patients are screened for periodontal disease, occlusal disturbances, caries, and craniomandibular disorders. Complete periapical radiographs are made; probing-depth, fremitus, and tooth mobility are recorded. Since the beginning of 1987, movement responses in each patient undergoing treatment are recorded by electrognathography (Sirognathograph, Siemens, Erlangen,
6. Disclusion by Hawley bite plane.
W. Germany) and analyzed by the Arthur Lewin program (Leworth cc Software, Siemens, Bensheirn, Germany, and Bio-Research, Milwaukee, Wis.) This examination and its computer analysis enable visualization of the functional pattern during chewing. Fifteen patients with severe vertical overlap were treated during the period 1975 to 1980 with the Hawley bite plane therapy. Twenty-six patients with similar conditions were treated during 1980 to 1988, five of whom were recorded with the Sirognathograph equipment before, during, and after treatment. All patients undergo an initial phase of therapy including oral care instructions, scaling, and root planing. In recent years a Sirognathograph equipment recording follows each stage of treatment, In the second stage of therapy, occlusal support was established by the Hawley bite plane (Fig. 6). Since 1980 this support has been achieved by forming the canine platform.10 A new vertical.dimension of occlusion is estab-
Fig. 7. Flat slope on lingual surface of maxillary canines, with light-cured composite resin
8. Disclusion by canine platform.
9. Deep vertical overlap before treatment.
10. New occlusal relationship after treatment.
lished by applying light-cured composite resin on the lingual surface of the maxillary canines (Figs. 7 and 8). During the treatment period (ranging from 6 to 18 months) root planing, curettage, and occlusal adjustment by selective grinding are performed. In patients with increased horizontal overlap of the canines, composite resin can be added to the facioincisal aspect of the mandibular canines. The Sirognathographic equipment recordings are made for each patient. Each patient is examined for functional movement while chewing gum and wine gum. 11,l2 The recorded information enables visualization of the functional range of movement and its possible effect during treatment phases. After completion of the treatment, the patients are followed every 4 to 6 months in a recall program.
All patients with deep vertical overlap who were treated by posterior tooth eruption demonstrated periodontal improvement verified by clinical and radiologic examination. A stable occlusion was achieved and a favorable anterior occlusal relation was established, eliminating trauma to soft and hard tissues (Figs. 9 and 10). Sirognathograph equipment recording before, during, and after completion of treatment revealed changes in chewing strokes. Uniformity and repeatability after completion of treatment was seen in contrast to an irregular chewing pattern observed in some patients before treatment. Six of 41 patients discontinued follow-up 3 years after completion of treatment. The remaining 35 patients continue to demonstrate stable occlusion, healthy periodontal condition, and minor changes in the anterior region.
Forty-one patients with severe vertical overlap were treated by using posterior tooth eruption. Fifteen were treated by occlusal splint therapy and 26 by using the canine platform.
Treating severe vertical overlap by tion demonstrated that periodontal clusal relations could be improved. posterior tooth eruption in patients
posterior tooth erupconditions and ocSimilar results with with advanced peri-
odontal disease have been reported.13 In these patients the Hawley bite plane was used. Since 1980 the modified canine platform has been preferred. Maxillary and mandibular teeth may erupt simultaneously. Esthetics or phonetics is not affected, and patient cooperation in wearing a treatment restoration is not needed. The canine platform method is an easily constructed chairside procedure. Follow-up of patients treated both by the Hawley bite plane and the canine platform revealed that the new occlusal relation achieved with the canine platform method is more stable and long lasting. This is probably because of the biologic protective mechanism since biting on the anterior teeth suppresses the activity of the elevator muscles. I4 Moreover, the canine platform remains in place, may add support to the posterior occlusion, and has a role in anterior guidance. Nevertheless, the canine platform needs to be checked periodically for integrity. Changes in the canine platform are often necessary because of chipping of the composite resin (four patients). In some patients treated with the Hawley bite plane, after satisfactory completion of treatment and removal of the splint, some occlusal changes occurred anteriorly and posteriorly that required adjustment. Most of the changes were in anterior vertical and horizontal overlap relations. The canine platform mode of treatment proved to be extremely successful since it enables posterior tooth eruption in both the upper and lower jaw. In contrast, the Hawley bite plane relieves only the lower posterior teeth for eruption. Periodontal health is improved and a stable occlusion is created. Recording with the Sirognathograph equipment revealed irregularity in chewing cycles. In some patients this improved after treatment with the canine platform method, in others no noticeable changes were observed. Further investigation is necessary. This approach is economical, efficient, does not require extensive restorative commitments, and it is not inconvenient to the patient.
established new occlusal relationships obtained were stable and long lasting. The method is efficient, inexpensive, and convenient to the patient. REFERENCES I. Posselt V. Physiology of occlusion and rehabilitation. 2nd ed. Oxford and Edinburgh: Blackwell Scientiic Publ, 1968;320. 2. Lee RL, Gregory GG. Gaining vertical dimension for the deep bite restorative patient. Dent Clin North Am 1971;15:743-63. 3. Graber TM. Orthodontics. Principles and practice. 3rd ed. Philadelphia: WB Saunders Co, 19’72;221,780,239-46. 4. Ricketts RM. A study of changes in temporomandibular relations associated with the treatment of class II malocclusion (Angle). Am J Ortbod 1952;38:918-33. 5. Begg PR. Begg orthodontic therapy and technique. Philadelphia: WB Saunders Co, 1971;191-9. 6. Schwartz M. Occlusal variations for reconstructing the natural dentition. J PROSTHET DENT 1986,55:101-5. 7. Dawson PE. Evaluation, diagnosis, and treatment of occlusal problems. St Louis: CV Mosby Co, 1974;301-11. 8. Ravindra N. The differential diagnosis and treatment of excessive overbite. Dent Clin North Am 1981;25:69-‘77. 9. Poison AM. The relative importance of plaque and occlusion in periodontal disease. J Clin Periodonto 1986,13:923-7. 10. Yaffe A, Ehrlich J. The canine platform: a modified method for posterior tooth eruption. Compend Contin Educ Dent 1985;6:382-6. 11. Van Rensburg LB. Electrognathographics and introduction to the clinician (I). Quintessence Int 1982,3:321-7. 12. Van Rensburg LB. Electrognathographics and introduction to the clinician (II). Quintessence Int 1982;4:423-36. 13. Amsterdam M. Periodontal prosthesis-twenty five years in retrospect. Alpha Omega 1974;67:8-52. 14. Storey AT. Neurophysiological aspecta of TM disorders. In: Laskin D, Greenfield W, Gale E, Rugh J, Neff P, Allen C, Ayer WA, eds. The President’s conference on the examination, diagnosis and management of temporomandibular disorders. Chicago: American Dental Association, June 1982;17-23. Reprint
DR. A. YAFFE HEBREW UNIVERSITY-HADASSAH P.O.B. 12ooO JERUSALEM ISRAEL
SCHOOL OF DENTAL MEDICINE
This study presents a different mode of treating severe vertical overlap by using the canine platform method. The
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