PEDIATRIC DENTISTRY/Copyright ©1984 by The American Academyof Pediatric Oentlstry Volume 6 Number 4 Rib implant for mandibular ankylosis in a five-year-old child: clinical report Paul E. Schneider, DDS, MSDMichael F. Zide, DDS Abstract trauma which is sufficient to produce hemarthrosis, meniscus disruption, or fracture of the condyle or This clinical report describes howa child with temporal plate can result in ankylosis. 3,6 The presence temporomandibularjoint ankylosis benefited from the combinedskills of the pediatric dentist, oral and of a scar may point toward a traumatic etiology for maxillofacial surgeon, and other health professionals. ankylosis, but the probability of ankylosis following TMJ injury is reported to be around 0.2%.9 Inflam- matory causes are rheumatoid arthritis, Felty’s syn- Temporomandibular joint (TMJ) dysfunctions are drome, Still’s disease, and Marie-Strumpell 1,2,1°,11 rare in young children. More than 50% of TMJ an- disease. Childhood infections including otitis kylosis conditions arise before age 10.13 The child media, dental infection, mastoiditis, parotid abscess, whose trauma leads to TMJ ankylosis becomes de- osteomyelitis, tuberculosis, actinomycosis, scarlet fe- bilitated and disfigured. The pedodontic and surgical ver, septic arthritis, and mastoiditis of the temporal managementof a 5-year-old child with bilateral an- bone can cause ankylosis after their spread to the 1"6"12 kylosis is described. TMJ. Paget’s disease, metastatic neoplasms, and the effects of radiation therapy also must be included in8,1 a3 differential diagnosis of TMJankylosis. Background Characteristics TMJ ankylosis is a fibrous or bony fusion of the condylar head of the mandible to the articulating por- TMJankylosis in children results in arrested con- tion of the temporal bone. 4 Mandibular movement is dylar growth. The loss of growth and function results restricted only in fibrous ankylosis, but with bony in muscle and bone atrophy and, in time, micro- ankylosis the patient’s mandible and temporal bone gnathia, microgenia, and retrognathia. ~,~2,~ Anky- are united and the TMJno longer functions normally. losis is more often unilateral, causing facial Both fibrous and bony anklyosis may allow some assymetry.5,8 The earlier the ankylosis occurs, the more movementat the incisors. A vertical or interincisal severe the deformity, s The tongue position, pattern opening of 5 mmor less indicates full bony union of of swallowing, activity of the muscles of facial expres- the5 mandible to the temporal bone. sion, and oral habits are functional causes or contrib- The three main causes of TMJanklyosis are trauma, utors to the deformity, is The child may ingest a poor inflammation, and infection. 6,7 Damageto the fragile diet which contributes to a failure to thrive and di- vasculature at the condylar heads during intrauterine minished growth. The restricted airway can cause fetal movementis a possible etiology for congenital problems with respiration and with articulation and ankylosis. 1,2,8 Traumasustained by the newborn dur- speechs,14 fluency, ing a difficult forceps delivery and trauma inflicted The psychological toll varies. Some children cope by an abusive adult have been implicated.1 Both un- adequately with the problem, but others are psycho- treated fractures or badly comminuted condylar head logically disabled by their disfigurement, ~* and be- fractures treated by immobilization for extended pe- comeshy, moody,and reclusive. Their oral restrictions riods have resulted in ankylosis. Any mechanical cause great frustrations during eating or speech. As PEDIATRIC DENTISTRY: December 1984Nol. 6 No. 4 259 a result they may be unable to adjust socially and have to be completed blindly. An intravenously ad- may5 have difficulty with school. ministered narcotic may be required to gain adequate cooperation for intubation. A local anesthetic also can Diagnosis be supplied to the nasal tissues to act as a vasocon- strictor. A fiberoptic pediatric bronchoscope may aid Certain characteristics help distinguish fibrous from in a difficult intubation.. Whennasotracheal intuba- bony anklyosis. Patients with fibrous anklyosis will tion cannot be completed, retrograde intubation find forceful openh~g of the mouth painful while bony through the cricothyroid membrane may be done. 4 ankylosis patients will not. Some fibrous anklyosis Tracheostomy may be necessary in establishing and patients will be able to protrude the mandible slightly maintaining the airway. while bony anklyosis patients will not. Photographs, cephalometric and panoramic radio- Surgical Options graphs, TMJ joint tomograms, or CATscans are valu- Several surgical options are available to treat an able in documenting the actual site and extent of ankylosed TMJ:21 excision of the bony area, 2° excision ankylosis.lS-17 In ankylosis the coronoid process usu- and implantation, or excision and grafting tissue (such ally is enlarged; in long-standing cases, the antegon- as a rib). The treatment of choice remains controver- ial notch appears severely depressed and the TMJ sial. area may be obliterated with dense sclerotic bone.6 When bony ankylosis is present, bone extending to the lingula (in a small child), muchof the ascend- Dental Treatment ing ramus, and sometimes the areas in which the second and third molars are forming may have to be Ankylosis of the TMJaffects the child’s preventive removed. An interpositioned implant, such as Pro- and remedial dental care. Poor oral hygiene is likely plast ®a, may prevent an open bite or reankylosis. 16 because toothbrushing is difficult, laborious, and may Autogenous grafting of a rib between the mandible have been abandoned in frustration. 15,18 The combi- and the temporal bone has several advantages. 22,2~ It nation of poor diet and inadequate home care prac- restores the continuity of the mandible, is not re- tices makes the child especially prone to dental caries 1%2° jected, and has desirable growth potential. The graft and periodontal disease. can grow to the contour of the mandible or be used The first dental visit may be to relieve a tooth- 19,2° to advance it. Less bone is removed from the man- ache. The child may not be able to tolerate in- dibular ramus if the mandible is advanced or the ra- traoral radiographs or study model impressions, mus lengthened. Finally, the rib often reforms in the anatomic landmarks are distorted, anesthetic admin- child’s chest. 23 Disadvantages to grafting include a istration is difficult, and access to the mouth is in- second surgical site in the patient’s chest, ~ the diffi- adequate. Therefore, prudence suggests delaying cult surgery, 2° and the unpredictable growth poten- definitive dental treatment until after surgical correc- tial~ of the graft. tion. Postoperative physiotherapy may maintain ade- quate vertical dimension~3 using intermittent forceful Treatment Team The child with an ankylosed TMJ is treated best by opening of the mouth with screw exercisors, tongue depressors, or other mechanical mouth openers. Such the coordinated efforts of a pediatric dentist and an therapy can be painful and traumatic to the teeth. In oral and maxillofacial surgeon. The pediatric dentist order to avoid dental injury, acrylic mouthguardsoften makes the stabilization surgical splint and during cor- arez~ made. rective surgery can provide emergency dental care. Usually the young pafients’s surgical sites have healed sufficiently in 4-6 weeks for remedial dental care to Clinical History be6 completed. A female Vietnamese child was unable to open her The pediatrician must evaluate the child’s nutri- mouth more than 3 mmor chew properly following tional status and ability to withstand surgery. The a single febrile seizure at age one year (Figure 1). The anesthesiologist should be prepared for a difficult na- symptompersisted and at age five her father brought sotracheal or orotracheal intubation. 16 Lateral neck her to the pedodontic clinic at LSU School of Den- radiographs may be helpful in evaluating the airway. tistry; her chief complaint was inability to open her Preoperative consultation with the anesthesiology mouth and chew food. She could tolerate extraoral department is important since a conscious nasotra- radiographs only. cheal intubation might be needed and rapport be- The child was well nourished but small (height and tween the child and anesthesiologist is critical. With weight less than 3rd percentile), her face was convex, ankylosis, the vocal chords cannot be visualized through the mouth and nasotracheal intubation may " Proplast-Vitek Corp; Houston, TX. 260 RIB IMPLANT FOR MANDIBULARANKYLOSIS: Schneider and Zide (By reducing the tray's thickness to 1-2 mm and maintaining its width to approximately that of a child's dental arch, it could be inserted into the child's mouth.) A surgical stabilization splint was fabricated to hold the mandible in an anterior and inferior position to encourage and direct symmetrical maxillary and mandibular growth. The stabilization splint was constructed by mount- ing study casts on an articulator using a face bow and an interocclusal record of the condyles in centric re- lation. The facial midline was marked on the maxil- lary cast and the anatomic midline was marked on the mandibular cast. The mandibular anatomic mid- line was aligned with the maxillary facial midline by FIGURE 1. The child's maximum oral opening before sur- completing the intended surgery on the mandibular gery was 3 mm. cast. A rope of uncured autopolymerizing resin was made in the