title: Masticatory function in patients with juvenile rheumatoid arthritis.
abstract: OBJECTIVE
  Children with Juvenile Rheumatoid Arthritis (JRA) rarely report temporomandibular joint (TMJ) pain, which may be due to pain avoidance mechanisms resulting in compromised masticatory function. This study examined the relationship between self-report measures of pain and dysfunction and measures of chewing performance in 44 JRA children and 34 normal controls.
  
  
  METHODS
  The children were divided into three groups: Group 1, JRA children with temporomandibular joint disorder (TMD); Group 2, JRA children without TMD; Group 3, normal control children without TMD. Both visual and analog scales of jaw pain, ability to chew, and quality of life were administered before and after chewing tasks. Children chewed standardized portions of an artificial food for 20 cycles and expectorated the particles into a cup. This process was repeated five times. Median particle size and a broadness of particle distribution index were measured. Also, the number of chewing cycles prior to the child's first swallow for a cube of carrot was recorded.
  
  
  RESULTS
  The broadness of particle distribution index was greater for Group 1 (P < 0.001) and Group 2 (P < 0.03) than for Group 3 with no difference in number of chews for carrot mastication among groups. Group 1 reported more pain and dysfunction before the chewing tasks than Groups 2 or 3 (P < 0.05). Interestingly, only Group 3 reported increased pain and decreased ability to chew after chewing tasks (P < 0.02).
  
  
  CONCLUSIONS
  Children with JRA compromise their masticatory function as a pain avoidance mechanism. Such findings may have profound implications with regard to the nutritional status for these children.
authors.affiliation: Department of Oral Maxillofacial Surgery/Pharmacology, Baylor College of Dentistry, USA. rharper@tambcd.edu
authors.forename: R P
authors.initials: RP
authors.lastname: Harper
authors.forename: C M
authors.initials: CM
authors.lastname: Brown
authors.forename: M M
authors.initials: MM
authors.lastname: Triplett
authors.forename: A
authors.initials: A
authors.lastname: Villasenor
authors.forename: R J
authors.initials: RJ
authors.lastname: Gatchel
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001171:Arthritis, Juvenile / Q000503:physiopathology*; D001362:Avoidance Learning; D016022:Case-Control Studies; D002648:Child; D018552:Daucus carota; D005157:Facial Pain / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006801:Humans; D007574:Jaw Relation Record; D008297:Male; D008409:Mastication; D010147:Pain Measurement; D010316:Particle Size; D012647:Self-Assessment; D018709:Statistics, Nonparametric; D013705:Temporomandibular Joint Disorders / Q000503:physiopathology*