Malocclusion and tooth-on-tooth trauma

Malocclusion and tooth-on-tooth trauma

While an uncommon option, odontoplasty can resolve some cases
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Jun 01, 2011

The two main indications for therapeutic intervention when dealing with malocclusions in veterinary dentistry are tooth-on-tooth trauma and tooth-on-tissue trauma. This article focuses on tooth-on-tooth trauma, but tooth-on-tissue trauma may also be occurring; both of these conditions must be addressed.

Treatment options for tooth-on-tooth trauma

The result of malocclusions involving tooth-on-tooth trauma is abnormal tooth wear that often results in dentin or pulp exposure in one or both teeth. Subsequent loss of tooth vitality is a likely end result of any tooth-on-tooth malocclusion. Intervention is indicated whenever this relationship occurs. Orthodontics, endodontics, extraction and, occasionally, odontoplasty are all possible treatment modalities. The decision on which treatment (or which combination of treatments) to use depends on the often complex arrangement present before and after attempts at resolution.

When evaluating malocclusions, the top consideration should always be the least-invasive treatment for the patient. The question then becomes: What is the most feasible line of therapy?

If, for instance, extractions are the obvious choice, it may not be what the pet guardian has in mind. If the condition dictates that orthodontic movement is also an option, and referral is available, orthodontics must be discussed and offered as an alternative.

Not only are careful evaluation and planned therapy critical in these cases, post-therapeutic anatomy must be evaluated to assess the new occlusion once adjustments have been made: Is there new tooth-on-tooth or tooth-on-tissue trauma present? If I alter the crown height of this tooth
2 mm, how will that affect the rest of the dentition?

Case study: Odontoplasty


Photo 1: A persistent deciduous right mandibular canine tooth (804) in a 10-month-old dog. This tooth was extracted.
A 10-month-old spayed female mixed-breed dog had a persistent deciduous right mandibular canine tooth (804) (Photo 1). Radiographs demonstrated near total root resorption, and the tooth was easily extracted.










Photo 2: The left mandibular canine tooth (304) is contacting the distal aspect of the left maxillary third incisor (203).
More important, the left mandibular canine tooth (304) was contacting the distal aspect of the left maxillary third incisor (203) (Photo 2). Sole contact of this type does not disperse occlusal forces evenly, but rather concentrates them on two teeth. Under normal conditions, occlusal contact is shared by multiple teeth, including the incisors and molars in dogs. Left alone, wear will likely progress to damage the incisor, exposing dentin and compromising tooth vitality. Mandibular canine contact with the palatal mucosa is also likely if wear continues.

Selective extractions, crown amputations and vital pulp therapy or movement are all options, but a simple, minimally invasive procedure called odontoplasty is the best option in this particular case.

Odontoplasty is not commonly used because its effectiveness is limited to select cases in which minor crown reduction is needed. Odontoplasty requires using a sterile, water-cooled, fine diamond bur to remove dentin and enamel, while not entering the pulp chamber. A minimum of 1 mm of dentin should be left coronal to the pulp chamber. Dental radiography is used to estimate this landmark.