Mandibular fracture repair in a harbor seal.

A 30-year-old captive female harbor seal (Phoca vitulina) bit down upon a metal ring within a hoop-net normally used to assist in securing the seal for routine physical examination. Radiographic examination performed under general anesthesia revealed a unilateral closed fracture of the rostral left mandible between the first and second premolar teeth. The rostral fragment was displaced ventrally and slight laxity of the mandibular symphysis was noted. The fracture was repaired surgically using an oral dental acrylic splint incorporating circumferential mandibular cerclage wire. The mandibular symphysis was stabilized using interdental wire between the right and left canine teeth. The fixation device was removed following evaluation of radiographs that showed signs of bony union 12-months postoperatively.

Influence of an interdental full pin on stability of an acrylic external fixator for rostral mandibular fractures in dogs.

OBJECTIVE: To determine total stiffness and gap stiffness of an external fixation system in a canine mandibular fracture gap model incorporating a full interdental pin as the only point of rostral fixation in a bilateral type-I external fixator. SAMPLE POPULATION: 10 canine mandibles. PROCEDURE: Bilateral mandibular ostectomies were performed between premolars 3 and 4. A type-I external fixator incorporating a full interdental pin was placed to stabilize a 0.5-cm fracture gap. Four pin configurations (intact mandibular bodies with fixator; ostectomized mandibular bodies and complete fixator; ostectomized mandibular bodies with caudal pins of rostral fragment cut; ostectomized mandibular bodies with all pins of rostral fragment cut) were tested in dorsoventral bending 5 times on each mandible. The full interdental pin remained intact in all configurations. Total stiffness and gap stiffness were determined for each configuration on a materials testing machine. RESULTS: Total stiffness of intact mandibles was significantly greater than that of ostectomized mandibles, regardless of external fixator configuration. However, total stiffness and gap stiffness were not significantly different among different external fixator configurations applied to ostectomized mandibles. CONCLUSION AND CLINICAL RELEVANCE: External fixator configurations with only the full interdental pin engaging the rostral fragment were as stiff as configurations that had 2 or 4 additional pins in the rostral fragment for the applied loads. External fixators for rostral mandibular fractures may be rigidly secured with rostral fragment implants applied extracortically, avoiding iatrogenic trauma to teeth and tooth roots.

Composite restorative dentistry.

Modern composite restorative materials offer the veterinarian greater flexibility in the repair of damaged teeth. An understanding of the make-up of these materials is essential to maximize the effectiveness of the repairs. Endodontic disease was once ignored and is now treated on a daily basis. Newer composite restorations offer an effective means of protecting the sensitive pulp from bacterial invasion and allow the veterinarian to restore the tooth to function.

Restorative dentistry. Crown therapy.

Not one post, core, margin, impression material, cement, or final restoration can be used in all clinical situations. This article does not discuss the merits and shortcomings of the numerous restorative concepts and techniques that exist, but rather has concentrated on those that the author believes are valid and applicable today. If one third or more of the anatomic crown remains, or if this is achieved by crown lengthening, a post may not be necessary; however, a crown restoration should definitely be considered. Veterinary dentistry cannot limit those variables that occur daily in clinical practice. Veterinarians must learn to work with these variables and spend less time trying to find the one that applies to all cases. When the basic concepts of how to retain the various restorative components and how to protect remaining tooth structure are understood, the ability to answer numerous questions that arise during the restorative process is facilitated and results in final restorations that are based on sound design principles.