Suspected Lateral Periodontal Cyst Presenting Concurrently with Canine Acanthomatous Ameloblastoma in a 2-Year-Old Standard Poodle.

Lateral periodontal cysts (LPCs) are odontogenic epithelial cysts composed of nonkeratinized epithelial cells that are in the category of developmental cysts, rather than inflammatory cysts. Lateral periodontal cysts are rare both in people and domestic animals; they are associated with vital teeth and located lateral to a tooth root. Lateral periodontal cysts are typically asymptomatic lesions that are characterized radiographically as a unilocular lucency with well-defined corticated borders. Canine acanthomatous ameloblastoma (CAA) is the most common odontogenic neoplasm in dogs and rarely presents as a cystic lesion. This case report describes the diagnosis and treatment of a cyst that occurred as a swelling apical to a gingival mass that was diagnosed histologically as CAA. Surgical management by conservative gingivectomy, cyst enucleation, and bone grafting was an effective treatment in this patient.

The Influence of Force Direction on the Fracture Pattern and Fracture Resistance of Canine Teeth in Dogs.

Biomechanical studies of the elongated canine tooth of animals are few, and thus our understanding of mechanical and physical properties of animal teeth is limited. The objective of the present study was to evaluate the influence of force direction on fracture resistance and fracture pattern of canine teeth in an ex vivo dog cadaver model. Forty-five extracted canine teeth from laboratory beagle dogs were standardized by hard tissue volume and randomly distributed among 3 force direction groups. The teeth were secured within a universal testing machine and a load was applied at different directions based on testing group. The maximum force to fracture and the fracture pattern classification were recorded for each tooth. After correcting for hard tissue cross-sectional area in a multivariate analysis, no significant difference in the amount of force required for fracture was apparent between the different force direction groups. However, the influence of force direction on fracture pattern was significant. The results of this study may allow the clinician to educate clients on possible causal force directions in clinically fractured teeth and, thus, help prevent any contributing behavior in the future.

Apical Microleakage in Root Canals Obturated With 2 Different Endodontic Sealer Systems in Canine Teeth of Dogs.

An apical dye leakage test was utilized to compare 2 endodontic sealer systems commonly used in veterinary endodontic treatment. Rotary instrumentation followed by injection of 2 different sealers (GuttaFlow 2 and AH Plus) and a single master cone obturation technique were compared. Following obturation and restoration, specimens were immersed in India ink for 48 hours. A tooth mineral clearing technique was utilized to render the tooth samples transparent. Subsequently, the apices were evaluated for prevalence and magnitude of apical dye penetration under magnification. Statistical analysis of the results revealed no significant differences in the prevalence or magnitude of apical dye penetration between groups.

Caudal Mandibular Bone Height and Buccal Cortical Bone Thickness Measured by Computed Tomography in Healthy Dogs.

OBJECTIVE: To characterize bone height and buccal cortical bone thickness of the caudal mandible of healthy dogs. STUDY DESIGN: Prospective original study. SAMPLE POPULATION: Client-owned dogs (n = 36). METHODS: Dogs were distributed by weight into 3 groups (<10, 10-20, >20 kg). Thirteen transverse plane computed tomography images were selected for each dog based on anatomic landmarks from the 4th premolar (PM4) through the 2nd molar. On each image, bone thickness was measured along the buccal surface of both mandibles from the alveolar margin to the ventral border in 3 mm increments. The number of 3 mm increments were recorded as an estimation of mandibular height. RESULTS: Buccal bone was generally thicker ventrally in the area studied with decreasing bone thickness over both roots of PM4 and the mesial root of the 1st molar (M1). Cortical bone thickness of <2.0 mm was measured across all groups at most locations 3 mm ventral from the alveolar margin. Mandibular bone height demonstrated significantly fewer (P < .05) 3 mm increments over the distal root of M1 in dogs >10 kg compared with the number of observations at the immediately mesial and distal locations. CONCLUSION: Thin cortical bone overlying the mesial and distal roots of PM4 and the mesial root of M1 limits use of these areas for application of monocortical anchorage devices. Decreased mandibular bone height at mandibular M1 may create a stress riser at this location, which along with thin cortical bone may explain why this is a common area for mandibular fracture.

Treatment of Bignathic Malocclusions With Multistage Active Force Orthodontic Movements in a Cat.

Abstract Untreated malocclusions may lead to negative oral health sequelae including, but not limited to, pain, dental trauma, periodontal disease, and endodontic disease. Thus, orthodontic treatments of malocclusion in companion animals are often pursued for reasons other than cosmesis. Treatment may provide a pain-free, functional occlusion with the opportunity for the best possible long-term oral health. This report describes the multistage orthodontic treatment of a bignathic malocclusion in a cat, highlighting the complexities and complications that may arise with orthodontic movement of multiple teeth.

Successful Treatment of Mandibular Nonunion With Cortical Allograft, Cancellous Autograft, and Locking Titanium Miniplates in a Dog.

Discontinuities of the mandible can occur for a variety of reasons including primary pathology of bone, pathologic fracture secondary to periodontal disease, and segmental resection for the treatment of neoplasia. Surgical intervention is necessary in many cases to establish normal occlusion and normal mandibular function. Rigid stabilization and treatment of these defects can be challenging due to the limited availability of bone for fixation as well as limited soft tissue coverage. This case report describes successful treatment of a nonunion fracture using cortical allograft and locking titanium miniplates. Complete osseointegration and bone healing were achieved, allowing for complete return to normal occlusion and function.

Extensive Maxillary Odontomas in 2 Dogs.

Two immature male dogs were presented for the treatment of extensive maxillary compound odontomas. In both cases, clinical evaluation and diagnostic imaging revealed extensive lesions invading and displacing anatomical structures of the maxilla. Histopathology confirmed the diagnoses in both cases. One dog was treated with partial rostral maxillectomy, and the other dog was treated with enucleation of the cystic lining and removal of tooth-like structures through a lateral rhinotomy utilizing an intraoral approach. This report illustrates the growth potential of maxillary compound odontomas in 2 dogs and highlights their subclinical appearance and excellent prognosis despite their extensive nature.

The Influence of Axial Grooves on Dislodgment Resistance of Prosthetic Metal Crowns in Maxillary Fourth Premolar Teeth of Dogs.

The reported failure rate for full veneer crowns in dogs is suboptimal, particularly in teeth with naturally poor retentive features such as the maxillary fourth premolar tooth of dogs. Although the data regarding crown retention on the maxillary fourth premolar in dogs are limited, there are data that suggest the crown failure rate could be similar to that of the canine tooth. Thus, methods to improve retentive features of the preparation design should be pursued. The objective of the present study is to quantify the influence of axial grooves on the dislodgment resistance of full veneer metal crowns in dogs. Crown dislodgment testing was performed on cast alloy dies of the maxillary fourth premolar tooth with unfavorable retentive features prepared with and without axial grooves, to quantify the difference in force required to dislodge a cemented full veneer crown. The force required to cause crown dislodgment was recorded for each crown. Statistical analysis revealed a significant increase ( P < .001) in the force required for crown dislodgment in teeth prepared with axial grooves compared to those prepared without axial grooves.

The Influence of Axial Grooves on Dislodgment Resistance of Prosthetic Metal Crowns in Canine Teeth of Dogs.

The reported failure rate for full veneer crowns of canine teeth of dogs is suboptimal, particularly in teeth with naturally poor retentive features, such as those with low height/diameter (H/D) ratios or high convergence angles (CAs). The objective of the present study was to evaluate the application of axial grooves in an effort to develop a crown preparation design that enhances the retention of full veneer crowns in dogs. Crown dislodgment testing was performed on cast alloy dies of canine teeth with unfavorable retention features (low H/D and high CA) prepared with (n = 14) and without axial grooves (n = 15) to evaluate the force required to dislodge a cemented full veneer crown. The crown/die units were secured within a universal testing machine and a load was applied at the 45° oblique direction from distal to mesial to replicate the vector encountered during biting-pulling action. The maximum force required to cause crown dislodgment was recorded for each crown. Statistical analysis revealed a significant increase in force required for crown dislodgment when axial grooves were included in the crown preparation design ( P < .001). Crown retention is improved in canine teeth with otherwise poor retention features when axial grooves are made in the labial and palatal/lingual walls during crown preparation.

Transmylohyoid orotracheal intubation in surgical management of canine maxillofacial fractures: an alternative to pharyngotomy endotracheal intubation.

OBJECTIVE: To describe the surgical technique of transmylohyoid orotracheal intubation in surgical management of maxillofacial fractures in dogs. STUDY DESIGN: Case series. ANIMALS: Dogs (n = 4) with maxillofacial fractures. METHODS: Transmylohyoid orotracheal intubation was used for airway management of dogs undergoing surgical repair of maxillofacial trauma. A stoma was surgically created by an incision through the skin, subcutaneous tissue, and mylohyoideus muscle immediately medial to the lingual cortex of the mandible at the level of the mandibular 1st molar tooth, so that an endotracheal tube could exit the oral cavity between the mandibular bodies bypassing the dentition. RESULTS: Transmylohyoid orotracheal intubation allowed excellent surgical visibility of the oral cavity and intraoperative control of occlusion during surgery. No complications were encountered during the procedure and the stoma healed without complication. CONCLUSIONS: Transmylohyoid orotracheal intubation is a safe, simple, and effective technique for bypassing the rostral oral cavity and dentition during surgical management of maxillofacial fractures.

Effect of particle size on calcium release and elevation of pH of endodontic cements.

BACKGROUND/AIM: Elevation of pH and calcium ion release are of great importance in antibacterial activity and the promotion of dental soft and hard tissue healing process. In this study, we evaluated the effect of particle size on the elevation of pH and the calcium ion release from calcium silicate-based dental cements. MATERIAL AND METHODS: Twelve plastic tubes were divided into three groups, filled with white mineral trioxide aggregate (WMTA), WMTA plus 1% methylcellulose, and nano-modified WMTA (nano-WMTA), and placed inside flasks containing 10 ml of distilled water. The pH values were measured using a pH sensor 3, 24, 72, and 168 h after setting of the cements. The calcium ion release was measured using an atomic absorption spectrophotometer with same sample preparation method. Data were subjected to two-way analysis of variance (anova) followed by post hoc Tukey tests with significance level of P < 0.05. RESULTS: Nano-WMTA showed significant pH elevation only after 24 h (P < 0.05) compared with WMTA, and after 3, 24, and 72 h compared with WMTA plus 1% methylcellulose (P < 0.05). Nano-WMTA showed significantly higher calcium ion release values compared to the other two groups (P < 0.05). CONCLUSIONS: Nano-modification of WMTA remarkably increased the calcium ion release at all time intervals postsetting, which can significantly influence the osteogenic properties of human dental pulp cells and as a consequence enhance mineralized matrix nodule formation to achieve desirable clinical outcomes. However, the increase in pH values mainly occurred during the short time postsetting. Addition of 1% methylcellulose imposed a delay in elevation of pH and calcium ion release by WMTA.

Evaluation of the Natural Crown Convergence Angle of Dog Carnassial Teeth.

A limiting factor in achieving an ideal crown preparation design is the natural morphology, principally the convergence angle, of the tooth. The natural convergence angle of the carnassial teeth in the dog has not been reported. The aim of the study reported here was to establish the natural crown convergence angle of the maxillary fourth premolar and mandibular first molar teeth in the dog. The natural convergence angle of the carnassial teeth in dogs was large and was not significantly associated with patient weight, age, or skull type.

The Influence of Crown Height to Diameter Ratio on the Force to Fracture of Canine Teeth in Dogs.

Previous work suggests that the tooth height to diameter ratio (H/D) may have an influence on the fracture resistance of dog canine teeth. Thus, it can be hypothesized that canine teeth with distal abrasion or teeth already requiring pulpal manipulation may benefit from a reduction in height and that an ideal H/D exists that balances tooth fracture resistance and tooth function. Therefore, a study was performed to investigate the influence of H/D on force to fracture and probability of fracture of canine teeth in dogs. Thirty extracted canine teeth from laboratory Beagle dogs were standardized by hard tissue volume and evenly distributed among three groups; unaltered H/D (group A), 10% reduction in H/D (group B), and 20% reduction in H/D (group C). The teeth were potted in clear autopolymerizing orthodontic acrylic and then secured within a universal materials testing machine. A displacement was applied at a speed of 1-mm/min to the distoocclusal line angle at an angle of 45 degrees to the long axis of the crown. The maximum measured force at the time of fracture represented the maximum force to fracture. A linear regression model showed a significant inverse relationship between H/D and force to fracture (p = 0.043; 95% CI-55.2 to -0.09). A margin of safety (MoS) analysis was performed to determine the probability of fracture by comparing normal force distributions of the measured force at fracture to that reported in a previous study, representative of normal biting-pulling loads on canine teeth. When 100% of the load was applied to a single unaltered canine tooth the probability of fracture was 36.7%. Decreases in H/D of 10% and 20% resulted in a decreased probability of fracture by 24.1% and 60.4%, respectively. A paired MoS analysis was conducted wherein the applied loads were distributed across 2 maxillary canine teeth according to their relative heights. Within the pair, a 20% decrease in H/D decreased the probability of fracture of that tooth by 86.5%, but increased the probability of fracture of the unaltered contralateral canine tooth by 54.4%. The findings of this study support the hypothesis that teeth with a lower H/D are more resistant to fracture. However, given the potential impact of crown reduction of a single canine tooth on the load redistribution to the remaining unaltered canine teeth, further investigation is needed to determine what H/D would be ideal. In addition, future studies could elucidate in which clinical scenarios the concept of H/D reduction could be implemented. The results of this study may have implications on the successful long-term management of traumatized canine teeth in dogs.

Classification and Epidemiology of Traumatic Dentoalveolar Injuries in Dogs and Cats: 959 Injuries in 660 Patient Visits (2004-2012).

The objective of this study was to determine the epidemiology of traumatic dentoalveolar injuries (TDI) in dogs and cats and to evaluate the applicability of a human classification system for TDI in dogs and cats. All patients diagnosed with a TDI were identified from the University of Wisconsin-Madison School of Veterinary Medicine Dentistry and Oral Surgery Service case log and the hospital patient processing software. The study population consisted of 621 dogs and cats, in a total of 660 patient visits from 2004 to 2012, admitted for oral treatment and subsequently diagnosed with at least one TDI Medical records including diagnostic imaging studies were reviewed to group the injury according to a classification system used in humans for TDI. Patient signalment, tooth injured, and number of injuries per patient were recorded and tabulated. The overall prevalence of TDI was 26.2%. The mean +/- SD number of TDI per patient was 1.45 +/- 0.85. All 14 classes of TDI recognized by the classification system utilized in humans were identified, and all (100%) TDI identified in this study were classifiable using this system. Enamel-dentin-pulp fracture was the most common TDI (49.6%). The most commonly injured teeth were the mandibular or maxillary canine teeth (35.5%). The most common age for dogs and cats with TDI were 3-6 years (33.0%) and 7-10 years (31.3%). With a frequency of 1 in 4 animals, TDI are common and represent a significant pet health concern. Most TDI are considered severe and require timely, and sometimes immediate, treatment. The adoption and utilization of a complete classification system, such as the one used in this study, is recommended in order to improve future epidemiological study of TDI in animals.

Comparison of the Diagnostic Image Quality of the Canine Maxillary Dentoalveolar Structures Obtained by Cone Beam Computed Tomography and 64-Multidetector Row Computed Tomography.

The objective of this blinded study was to validate the use of cone beam computed tomography (C) for imaging of the canine maxillary dentoalveolar structures by comparing its diagnostic image quality with that of 64-multidetector row CT Sagittal slices of a tooth-bearing segment of the maxilla of a commercially purchased dog skull embedded in methylmethacrylate were obtained along a line parallel with the dental arch using a commercial histology diamond saw. The slice of tooth-bearing bone that best depicted the dentoalveolar structures was chosen and photographed. The maxillary segment was imaged with cone beam CT and 64-multidetector row CT. Four blinded evaluators compared the cone beam CT and 64-multidetector row CT images and image quality was scored as it related to the anatomy of dentoalveolar structures. Trabecular bone, enamel, dentin, pulp cavity, periodontal ligament space, and lamina dura were scored In addition, a score depicting the evaluators overall impression of the image was recorded. Images acquired with cone beam CT were found to be significantly superior in image quality to images acquired with 64-multidetector row CT overall, and in all scored categories. In our study setting cone beam CT was found to be a valid and clinically superior imaging modality for the canine maxillary dentoalveolar structures when compared to 64-multidetector row CT.

Optimized canine dental computed tomographic protocol in medium-sized mesaticepahlic dogs.

The purpose of this study was to develop an optimized imaging protocol for canine dental imaging using single-detector row CT and multidetector row CT. Two medium-sized mesaticephalic cadaver dog heads were scanned using varying slice thickness, sequential vs. helical scanning mode, sequential CT table increment, pitch, image reconstruction algorithm, and an additional moderate edge enhancement filter. For each series, two reviewers scored dental roots as not visible (score: 0), partially visible (score: 1) or completely visible (score: 2). Sharpness of the dento-alveolar margin was scored as blurry (score: 0), sharp (score: 1) or very sharp (score: 2). Consensus reader scores were compared among CT protocols. For single-detector row CT, complete visualization of all tooth roots was only achieved with 1 mm slice thickness and image interval sequential or helical series (pitch of 1 or 2) using a high-frequency image reconstruction algorithm with or without additional edge enhancement. For four-detector row CT, complete visibility of all tooth roots was recorded in all series. For single-detector row CT, all medium frequency algorithm series yielded blurry margin scores and all other series yielded sharp margin scores. For four-detector row CT, sequential and helical 0.5 mm thickness images yielded very sharp dento-alveolar margin scores, whereas the 1 mm series yielded only sharp margin scores. Authors concluded that the optimal dental imaging protocol was a sequential mode 1 mm slice thickness and interval with a high-frequency image reconstruction algorithm and an additional moderate edge enhancement filter.

Clinicopathologic characterization of oral pyogenic granuloma in 8 cats.

This case series characterizes the clinicopathologic features and treatment of oral pyogenic granuloma in 8 cats. The cats reported here were patients originating from collaborative efforts at an academic clinical teaching hospital and a specialty dentistry/oral surgery referral practice. Although the initial biopsy results were variable, in all cases the diagnosis reflected an inflammatory process. A second clinicopathologic evaluation of these cases determined that all lesions were consistent with oral pyogenic granuloma. The location of the lesion was consistent among all cats within the present study Lesions developed at the vestibular mucogingival tissues of the mandibular first molar teeth. We propose that malocclusion and secondary traumatic contact of the ipsilateral maxillary fourth premolar tooth with the mandibular soft tissues is a possible contributing factor in the etiopathogenic mechanism.

Effect of preparation surface area on the clinical outcome of full veneer crowns in dogs.

Crown therapy is commonly used in veterinary medicine to provide support to teeth which have previously fractured, received root canal therapy, have significant wear, or experienced other detrimental removal of tooth substance. As with several aspects of veterinary medicine, many of the recommendations or guidelines for crown therapy originate from human dentistry, which are then transferred to veterinary patients. Due to the significant difference in the anatomy of teeth and function of the oral cavity between humans and dogs, these guidelines need to be studied to determine the appropriateness of their use in veterinary patients. This article evaluates the relationship between surface area of the preparation and clinical outcome of full veneer crown therapy of the canine tooth in dogs. Although there appeared to be a positive relationship between preparations with greater surface area and successful clinical outcome, it was not found to be statistically significant.

Surgical reconstruction of a composite nasomaxillary and superior labial defect in a dog with a fascia lata graft, titanium mesh implant and angularis oris axial pattern flap.

Objective: To document the successful surgical reconstruction of a composite nasomaxillary and superior labial defect using a fascia lata graft, titanium mesh and angularis oris axial pattern flap in a dog. Case summary: An estimated 2-year-old female intact mixed-breed dog was presented with a composite (hard and soft tissue) nasomaxillary defect, suspected to be caused by a chemical burn. Physical examination revealed nasal discharge, exposed bilateral maxilla and nasal bone, nasomaxillary fistula with air movement, and intrinsic discoloration of the left maxillary canine tooth. The soft tissue lesion extended from the nasal planum rostrally to the medial canthus of the left eye distally and from the right maxillary bone to include a full thickness loss of the left maxillary labium laterally. Computed tomographic images of the head showed chronic osteomyelitis of the maxilla, zygomatic and nasal bones with nasomaxillary fistula and numerous exposed roots of the left maxillary premolars. Staged surgical procedures to address the dentition and nasomaxillary defect were planned. The first procedure consisted of the extraction of periodontally compromised left maxillary premolars, and standard root canal therapy of bilateral maxillary canine teeth. The second procedure consisted of debridement of the non-vital soft and hard tissues and surgical reconstruction of the nasomaxillary defect after virtual surgical planning. Head computed tomography performed 5 months post-operatively revealed a decrease in the size of the osseous defect as well as the resolution of rhinitis. Clinical relevance: This case demonstrates the feasibility of using a combination of soft tissue graft, titanium mesh, and axial pattern flap in managing nasomaxillary defects. Such defects can lead to chronic rhinitis, infection, discomfort, and long-term morbidity. This case report provides a novel but practical approach for managing defects in the nasomaxillary region in dogs.

Novel Management of Masticatory Myositis in Three Dogs with a Selective Janus Kinase (JAK-1) Inhibitor.

Masticatory myositis (MM) is an inflammatory myopathy reported in dogs and is characterized by inflammation of the masticatory muscles (temporalis, masseter, and pterygoid muscles). Immunosuppressive therapy is the current recommended treatment for MM and may involve glucocorticoids, cyclosporine, azathioprine, mycophenolate mofetil, leflunomide, or a combination of these treatments that are slowly tapered to the lowest effective dose. However, side effects from multimodal medical therapy and complications associated with MM relapses have been reported. The purpose of this case series was to report oclacitinib as a treatment alternative to traditional medical management of MM. The intent of this alternative is to manage side effects from glucocorticoid use. Oclacitinib (1mg/kg per os q12h) was used solely for treatment of MM in three dogs. The dogs were followed up to >6 months after oclacitinib administration. An increase in oral range of motion, as determined by gape angle, was noted in all three dogs. However, a corresponding drop in antibody titers (2M fiber) did not occur. All dogs showed improvement in overall clinical management of MM, side effects from glucocorticoids, and clinical signs related to chronic prednisone use. Larger controlled trials with consistent measurements (interincisal distance, gape angle) and 2M fiber antibody titers are indicated to further assess validation of oclacitinib treatment of MM. The clinical outcome of all dogs was considered successful.