Temporomandibular disorders and bruxism in childhood

Abstract
Bruxism is the non-functional clenching or grinding of the teeth that may occur during sleep or, less commonly in the daytime in 5-20% of adults and about 30% of 56 year old children. Although research on bruxism is extensive, its etiology remains debatable. There is some literature to suggest that bruxism is correlated with temporomandibular disorders (TMDs) and malocclusion. The aim of this article is to present the course of this condition in a case of bruxism coupled with TMD with special emphasis on the importance of accurate diagnosis of maxillofacial pain. We also report an association between supernumerary teeth and TMDs that has not been reported earlier in the literature.

Introduction

The diagnosis and treatment of bruxism and associated temporomandibular disorders (TMDs) in children and young adults has received increased attention in the past 20 years. The most prevalent clinical signs of TMD are temporomandibular joint (TMJ) sounds, limitation of mandibular movements, TMJ and muscle tenderness, headache, TMJ sounds and bruxism. The prevalence of TMD in children varies widely in the literature, from 16% to 90% in children. The etiology of TMD is considered to be multifactorial and is still considered controversial. Possible causal factors include different structural parameters, psychosocial variables, acute trauma, occlusal interferences, stress and functional mandibular overload variables (e.g., parafunctional habits, grinding or bruxism, etc.).

The term bruxism is defined as an involuntary rhythmic or spasmodic non-functional gnashing, grinding or clenching of teeth. Reported prevalence for bruxism in children ranges from 5% to 100%. Various theories regarding its etiology fall into the following categories: occlusion related and psychological and originating within the central nervous system.

Myofacial pain and muscular hypertrophy, TMJ structural damage and non-restorative sleep are serious consequences of bruxism. Trauma to dentition and supporting tissues include thermal hypersensitivity, tooth hypermobility, injury to the periodontal ligament and periodontium, etc. The aim of this article is to present the course of the condition in a child with bruxism associated with TMD attributable to supernumerary teeth and malocclusion.

Case Report

History

A 7 year old boy was brought to the Department of Pediatric and Preventive Dentistry by his parents with the chief complaint of pain in the lower left back tooth region and history of grinding sounds during sleep often heard by his parents since 4 years of age. Parents further revealed that the child suffered from early morning pain in the right "ear region" for the last 3 weeks and was being treated for it by his pediatrician with analgesics but without much success. His medical history was uneventful and, during consultation, the patient was very pleasant and interactive.

Clinical examination

Intraoral clinical examination showed that two supernumerary teeth (mesiodentes) were observed on the ridge causing abnormal spacing and premature contact interfering with occlusion. Further examination revealed numerous carious lesions in the primary dentition. Pronounced attrition was observed in most of the primary teeth. Neither mouth-opening limitation or deviation nor clicking was detected during the examination of the TMJ.

Radiographic examination

Radiographic examination confirmed pronounced wear on primary teeth and the presence of two well-formed mesiodentes between the upper central incisors.

Course of condition

The following four stage treatment plan was developed:

Surgery: Surgical extraction of the supernumerary and the grossly decayed teeth
Restorative treatment: Pulp therapy with full-coverage stainless steel crowns over the remaining primary teeth
Orthodontic correction: Treatment for malocclusion, i.e. protruded upper incisors and midline diastema (spacing)
Referral for psychological evaluation: Followup visits were scheduled every second month and the patient was followed-up for 9 months in order to verify tooth wear and monitor eruption of permanent teeth. Psychological evaluation by the specialist showed the child as normal. Two weeks after the surgical and restorative phase, the patient reported that the morning right side TMJ area pain had stopped completely and 7 months post-operatively the parents reported a reduction of sleep grinding sounds in their child.

Discussion

Bruxism is believed, by most researchers, to be one of the leading causes of TMD. Besides bruxism, TMDs may also be caused by malocclusion, like a premature contact or due to supernumerary teeth as in the present case. Sonnesen et al. concluded in their study that errors of tooth formation in the form of agenesis or peg-shaped lateral teeth showed a significant association with signs and symptoms of TMD. But, in the present case, the presence of supernumerary teeth was related to symptoms of TMD and this association has not been reported earlier in the literature. Ramjford et al. suggested that occlusal abnormalities that prevent stable occlusion of the mandible may be a cause of bruxism and the mechanism is believed to be an alteration of definite afferent impulses originating in the periodontium or a lower threshold of initiation. Therefore, surgical extraction of supernumerary teeth was indicated to correct the malocclusion in the present case. This case report highlights the presentation of a case of bruxism with TMJ symptoms that was found to be related to supernumerary teeth and malocclusion. This was further corroborated as the symptoms resolved significantly after the surgical extraction of the supernumerary teeth and with orthodontic treatment for malocclusion.

What this case report adds?

This case report highlights the presentation of a case of bruxism with TMJ symptoms that were found to be related to supernumerary teeth and malocclusion.
The above-mentioned association has not been reported earlier in the literature.
The importance of multidisciplinary treatment is highlighted taking into consideration the multifactorial etiology of bruxism and TMDs.