Use of activator appliances in pediatric patients treated with costochondral grafts for temporomandibular joint ankylosis: Analysis of 13 cases

1414

DISCUSSION

controversy exists and further prospective studies to compare the effects of surgery plus postoperative orthodontic activator therapy with a control group of patients treated with surgery alone, are needed before more definite conclusions can be made as to the actual benefit of these devices. To our knowledge, such studies have not yet been reported. Such a study would address the precise role of activator appliances and help the profession decide whether it is the activator alone that produces favorable results and prevents reankylosis, or if other factors are involved.

9. 10. 11. 12. 13. 14.

References 1. Kaban LB: Acquired abnormalities of the temporomandibular joint, in Kab& LB: Pediatric Oral and Maxillbfacial Surgery. Philadelohia. PA, Saunders. 1990. DD 319-341 2. Munro I, bhen Yd, Park BY: S&u%aneous total correction of temporomandibular joint ankylosis and facial asymmetry. Plast Reconstr Surg 77:517, 1986 3. Norman JE: Ankylosis, in Norman JE, Bramley P: Textbook and Color Atlas of the Temporomandibular Joint, chap 18. London, Wolfe, 1990, pp 151-157 4. Kent JN, Misiek DJ: Biomaterials for cranial, facial, mandibular and TMJ reconstruction, in Fonseca RJ, Walker RV: Oral and Maxillofacial Trauma, vol 2, chap 29. Philadelphia, PA, Saunders, 1991, pp 917-921 5. Silvestri A, Natali G, Iannetti G: Functional therapy in hemifacial microsomia. J Oral Maxillofac Surg .54:271, 1996 6. Ware WH: Management of skeletal and occlusal deformities of hemifacial micromosmia, in Bell WH, Profitt WR, White RP: Surgical Correction of Dentofacial Deformities, vol 2, chap 18. Philadelphia, PA, Saunders, 1980, pp 1386-1389 7. Heffez L, Doku C: The Goldenhar syndrome: Diagnosis and early surgical management Oral Surg Oral Med Oral Path01 58:2, 1984 8. Fukata K, Jackson IT, Topf JS: Facial lawn mower injury treated

15.

16. 17. 18. 19. 20. 21. 22.

by a vascularized costochondral graft J Oral Maxillofac Surg 50: 194, 1992 Kent JN: Comparative study TMJ reconstruction with costochondral grafts. J Oral Maxillofac Surg 53:127, 1995 (suppl 4) Ware WH, Brown SL: Growth center transplantation to replace mandibular condyle. J Maxillofac Surg 9:50, 1981 Oritz-Monastario F, Fuente de1 Campo A: Early skeletal correction of hemifacial microsomia, in Caronni E (ed): Craniofacial Surgery. Boston, MA, Little Brown, 1985, p 401 Munro IR, Phillips JH, Griffin G: Growth after construction of the temporomandibular joint in children with hemifacial microsomia. Cleft Plate J 26:303, 1989 Al Kayat A, Bramley P: A modified preauricular approach to the temporomandibular joint and malar arch. Br J Oral Surg 17:91, 1979 Norman JE: Surgical access and its applied anatomy, in Norman JE; Bramley P: Textbook and Color Atlas of the Temporomandibular Joint, chap 2. London, Wolfe, 1990, pp 26-30 Lindqvist C, Pihakari A, Tasanen A, et al: Autogenous costochondral grafts in temporomandibular joint arthoroplasty: A survey of 66 artbroplasties in 60 patients. J Oral Maxillofac Surg 14:143, 1986 Macintosh RB, Henny FA: A spectrum of application of autogenous coslochondral grafts. .I Oral Maxillofac Surg 5:275, 1977 Poole MD: A composite flap for early treatment of hemifacial microsomia. Br J Plast Surg 42:163, 1989 Moss ML, Salentijn L: The primary role of functional matrices in facial growth. Am J Orthod 56:566, 1986 Okada M: An experimental study on the growth of the rat mandibular condyle by means of subcutaneous transplantation. Univ Osaka Dent J 22:21, 1977 Petrovic AG, Stutzmann JJ, Oudet C: Condylectomy and mandibular growth in young rats. Proc Finn Dent Sot 77:139, 1981 Poswillo D: Experimental reconstruction of the mandibular joint. Int J Oral Surg 3:400, 1974 Ellis E, Carlson DS: Histological comparison of the costochondral, sternoclavicular and temporomandibuiar joints during growth in Macaca mulatta. J Oral Maxillofac Surg 44:312, 1986

J Oral Maxillafac Surg 55:1414-1416, 1997

Discussion Use of Activator Appliances in Pediatric Patients Treated With Costochondral Grafts for Temporomandibular Joint Ankylosis: Analysis of 13 Cases Christian Lindqvist, MD, DDS Helsinki

University,

Helsinki,

Finland

Reconstructionof the temporomandibulararticulation is one of the mostdemandingchallengesin maxillofacial surgery. Goals not only include rehabilitation of the complex mechanism of the normal joint, but also restoration of facial symmetry, occlusion andmastication.As advancedtemporomandibular joint (TMJ) disease can lead to disturbances in

ular growth

imposes

additional

constraints

on the recon-

structive process.The most commongeneralindication for TMJ arthroplasty is the various forms of ankylosis, which result in restricted

mouth opening

and disturb masticatory

function. In most cases,trauma or rheumatoiddiseaseis responsiblefor developmentof the ankylosis. Middle-ear infection and osteomyelitis are now infrequent causesof ankylosis.Various formsof dysplasiaandmandibulardeformity can also give rise to indicationsfor joint arthroplasty, but in such conditions

additional

mandibular

and maxillary

surgeryis often necessary.‘-’ The advantagesof costochondralgrafting are the biologic andanatomicsimilaritiesof the graft materialto the condyle, low morbidity and regenerationof donor sites,and demonstratedgrowth potentialin juveniles.8,9Severalexperimental

thesefeatures and functions, it often gives rise to major indicationsfor arthroplasticprocedures.Alleviation of pain

studies have shown that rib cartilage has characteristics similar to thoseof the mandibularcondyle.8,‘0~11 This makesit

is also of great importance,

more likely that growth adaptationand function will occur

especially in considering

surgical

treatmentof degenerativejoint disease.In children,mandib-

at the new site. However,

despite the ideal intrinsic

and

CHRISTIAN

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LINDQVIST

adaptive growth characteristics of the costochondral junction, difficulties can also be associated with rib grafting. The most commonly encountered late problem is the uncontrolled, unpredictable growth.7X9X’2 In the interesting study reported, describing costochondral grafting in children, facial trauma was considered to be the cause of the growth disturbance in 11 of 13 cases. However, no information is given about the time of injury, nature of the trauma (a condylar fracture is mentioned in case 5) definitive diagnosis, or treatment. It must be assumed that primary diagnostics, therapy and follow-up were at least partly unknown. On presentation, the 13 children were on average 8 years old (range 5 to 14 years). Maximal interincisal opening (MIO) ranged from 1 to 15 mm (mean 6.2 mm). Extent of lateral excursions and of protrusion movements are not reported. The operative procedure included the following: 1) aggressive total excision of the ankylotic segment, 2) coronoidectomy on the affected side, 3) coronoidectomy of the opposite side, if necessary (when the jaw failed to mobilize adequately after ipsilateral condylectomy-coronoidectomy), 4) lining of the joint with temporalis fascia, or the native disc if it could be salvaged, 5) reconstruction of the joint with a costochondral graft, 6) creation of an open bite on the affected side to permit settling of the bone graft and allow the ramus to be lengthened primarily, 7) early mobilization with minimal maxillomandibular fixation (MMF) of no more than 3 weeks, and 8) aggressive physiotherapy. No information is given about length of grafts or amount of cartilage on the grafts. Nine of the 13 patients underwent costochondral transplantation with additional postoperative therapy using removable activator appliances. Four patients, in whom follow-up seems to have been less than adequate, did not undergo activator treatment. Only the former group exhibited satisfactory clinical results. However, no criteria are given regarding what constitutes a successful result, and no information is available on MI0 or amount of mandibular excursion. The authors state that long-term clinical results (followup was from 2 to 9 years) revealed “costochondral growth center transplants to be effective in restoring mandibular growth on the affected side.” Several factors related to growth, function, and symmetry could be “better controlled only in those cases that underwent orthodontic activator therapy postoperatively and were followed closely.” Although I do not doubt the truth of the previous statements, I wonder whether results from this type of study can, in fact, prove the hypothesis. Mandibular growth is thought to correlate with range of translatory movement of the condyle. When treating pediatric condylar trauma, especially high condylar fractures, functional treatment is of major importance to achieve normal, straight, opening, and symmetric mandibular growth. This also holds true in relation to postoperative treatment of patients who have undergone costochondral TMJ grafting. The younger the patient, the more important is such therapy. A patient who fails to follow the training program will probably exhibit a poor result, irrespective of any activator treatment. On the other hand, the activator can be considered a functional appliance, and a patient who co-operates with his or her surgeon and orthodontist will probably experience a favorable result. Rigid fixation of the graft, by eg, metallic AO-screws, or, preferably, bioresorbable ones, facilitates postoperative training programs. No MMF should now be necessary after operating on a child with TMJ ankylosis. Several studies have shown that costochondral grafts respond to the dynamic, morphologic changes occurring during the growth period in children and young adolescents.3*5.9

However, a major problem with costochondral transplantation is the unpredictable growth of the transplant. Overgrowth of a graft is a phenomenon that has not been satisfactorily explained. In our series of 95 costochondral transplantations we diagnosed overgrowth of the graft in two cases.13 However, our patients were of different age, and not only juveniles. Although secondary procedures are performed in such cases, it is not unusual for growth to continue, necessitating several operations. In the present series there were no cases of graft overgrowth. However, I doubt whether activator treatment could, in fact, prevent overgrowth. On the basis of a series of investigations by Peltomaki et al,” it was concluded that: 1. Costochondral grafts do not adapt to the growth velocity of the transplantation site. 2. The grafts are endowed with a tissue-separating potential, which is closely related to the amount of cartilage in the graft. The potential for growth of the costochondral graft is influenced by intrinsic, humoral/hormonal factors. Biomechanical stimulus is not indispensable for the continuation of costochondral graft growth. Mandibular movements do not have a major impact on the growth of costochondral graft. The histologic appearance of rat and human costochondral junctions do not essentially differ from each other. It would therefore seem that costochondral grafts might grow unrelated to their functional environments, and that by varying amounts of cartilage in the graft, subsequent growth can also be varied. The authors should be congratulated for their presentation of results relating to an interesting series of pediatric patients with TMJ ankylosis and mandibular growth disturbances treated by costochondral arthroplasty. Favorable clinical results were achieved in cases in which operation was followed by activator treatment and close monitoring. Although I believe more in active functional therapy per se, the results show clearly that a good clinical outcome cannot be expected solely on the basis of aggressive total excision of the ankylotic segment, coronoidectomy, temporal fascia relining of the fossa, and rigid fixation of the costochondral graft. Equally important is proper postoperative functional therapy and close monitoring. The hypothesis relating to the importance of amount of cartilage needs to be tested in additional experimental and clinical studies.

References 1. MacIntosh RR, Henny FA: A spectrum of application of autogenous costochondral grafts. J Maxillofac Surg 5:257, 1977 2. Obwegeser HL: Simultaneous resection and reconstruction of parts of the mandible via the intraoral route in patients with and without gross infections. Oral Surg 21:693, 1966 3. Kennett S: Temporomandibular joint ankylosis: The rationale for grafting in the young patient. J Oral Surg 3 1:744, 1973 4. Freihofer HP, Perk0 MA: Simultaneous reconstruction of the area of the temporomandibular joint including the ramus of the mandible in a postrauma case. J Maxillofac Surg 4:124, 1976 5. Tasanen A, Leikomaa H: Ankylosis of the temporomandibular joint of a child. Report of a case. Int J Oral Surg 6:95, 1977 6. Lindqvist C, Pihakari A, Tasanen A, et al: Autogenous costochondral grafts in temporomandibular joint arthroplasty. A survey of 66 arthroplasties in 60 patients. J Maxillofac Surg 14:143, 1986 7. James DR, Irvine GH: Autogenous rib grafts in maxillofacial surgery. J Maxillofac Surg 11:201, 1983 8. Lindqvist C, Jokinen J, Paul&u P, et al: Adaptation of autoge-

1416

9. 10. 11. 12.

nous costochondral grafts used for temporomandibular joint reconstruction: A long-term clinical and radiologic followUD. J Oral Maxillofac Surg 46:465, 1988 Ware WH, Brown SL: Growth center’transplantation to replace mandibular condyles. J Maxillofac Surg 9:50, 1981 Durkin JF, Heeley JD, Irving JT: The cartilage of the mandibular condyle. Oral Sci Rev 2:29, 1973 Poswillo D: Experimental reconstruction of the mandibular joint. Int J Oral Surg 3:400, 1974 Ware WH, Taylor RC: Cartilaginous growth centers trans-

DISCUSSION

planted to replace mandibular condyles in monkeys. J Oral Surg 24:33, 1966a 13. Lindqvist C: TMJ reconstruction and rehabilitation using costochondral and alloplastic grafts. Scandinavian Association of Oral and Maxillofacial Surgeons, XXVth Anniversary Conference, Nyborg Strand, Denmark, 1990, p 16-17 14. Peltomaki T: Growth of the costochondral junction and its potential applicability for the reconstruction of the mandibular condyle. Thesis, University of Turk”, Finland, 1993, P 60