Gingival Mucoperiosteal Fibroma-Clinical, Imaging, and Histological Review of a Novel Oral Fibroma in 27 Dogs.

This case series describes the clinical, imaging, and histological features of 27 lesions diagnosed as a benign fibrous mass not previously described in veterinary literature. The authors propose the name gingival mucoperiosteal fibroma (GMPF) to describe these fibrous lesions found in dogs. Histologically, GMPF is characterized by a lack of odontogenic tissue and various degrees of ossification. GMPFs affect adult dogs with an average age of 95 months (range 24-156 months) and appear as expansile growths with superficial appearance matching the surrounding gingiva. The mandibular incisive region is the most commonly affected region (n = 13) and most cases have some level of bone proliferation radiographically (n = 14). Histological examination of the masses shows poorly cellular fibrous tissue with thick interwoven collagen fibers. Bony invasion by the mass was not noted, though histological proliferation of bone was seen in 17 lesions. Surgical resection was curative in all cases when performed, and no recurrence was seen at time of follow-up. Fibrous lesions of the oral cavity in dogs are poorly defined and categorized, though numerous lesions have been described in both human and veterinary literature.

Characterization of Oral Pathology in Cats Affected by Patellar Fracture and Dental Anomaly Syndrome (PADS).

Patellar fracture and dental anomaly syndrome (PADS) is a congenital bone disease of cats that is characterized by atraumatic bone fractures (most commonly the patella), the persistence of deciduous teeth, and impaction of permanent teeth. Jaw swelling due to osteomyelitis is often the reason that cats with PADS are presented for veterinary dental care. The clinical history, oral examination findings, dental radiological findings, and histopathology were evaluated for 13 cats with dental and skeletal pathology consistent with PADS, including 9 with osteomyelitis. Cats in this study were predominantly domestic shorthair (12 of 13 cats), and there was no apparent sex predilection. All cats had multiple persistent deciduous teeth and multiple impacted permanent teeth, although the number of persistent and impacted teeth varied. Osteomyelitis of the jaw typically occurred within the first 4 years of life. Osteomyelitis of the mandible was 4 times more common than osteomyelitis of the maxilla. Histologically, osteomyelitis was chronic, neutrophilic, and osteoproliferative. Necrotic bone was confirmed in 67% of osteomyelitis lesions. Histological evaluation of jaws without inflammation demonstrated abnormal amounts of unmodeled bone, abnormally dense bone, and retention of cartilage in the caudal mandible. Three cats in the study had mandibular distoclusion and 2 had concurrent paronychia. To obtain a favorable clinical outcome in PADS cats with jaw swelling, prompt and aggressive surgical treatment of osteomyelitis is required. Extraction of persistent deciduous teeth and impacted permanent teeth is recommended when there is associated periodontitis or osteomyelitis.

Feline maxillary sarcoma: clinicopathologic features of spindle cell sarcomas from the maxilla of 25 cats.

CASE SERIES SUMMARY: Feline maxillary sarcomas are aggressive spindle cell neoplasms that occur within the maxilla, palate and upper lip of cats. This diagnosis includes fibrosarcoma and sarcomas with indeterminate histomorphology, excluding melanocytic tumors and sarcomas that can be differentiated by histomorphology. In this study of feline maxillary sarcomas in 25 cats, the cats' ages ranged from 4 to 16 years (median 12.5). These sarcomas presented as smooth thickenings or mass lesions of the gingiva and palate, often involving both the right and left quadrants of the maxilla. Radiographic bone loss was typically absent to mild at the time of diagnosis. Histologically, feline maxillary sarcomas were composed of spindle cells with varying amounts of fibrous stroma and mild inflammation. Metastasis was not documented for any cat in the study, although clinical staging was limited. Cats were often euthanized because of local recurrence following incomplete tumor excision and local tumor progression. Median survival time from the date of histologic diagnosis was 70 days (n = 12). RELEVANCE AND NOVEL INFORMATION: Feline maxillary sarcomas are aggressive neoplasms that may be difficult to differentiate from a benign, reactive process or other types of spindle cell neoplasms. Our findings indicate that feline maxillary sarcoma has distinctive clinical and histopathologic features, and the information provided in this paper will facilitate early and specific diagnosis of this tumor.

Characterization and Classification of Keratinized Odontogenic Cysts in 29 Dogs.

This retrospective case series presents a unique group of odontogenic cysts that are lined by heavily keratinized epithelium and contain laminated keratin. Keratinized odontogenic cyst (KOC) is proposed as appropriate terminology for the described lesions. The series evaluates cysts from 29 dogs, including clinical presentation, diagnostic imaging, and histopathology. All 29 lesions occurred in tooth bearing regions of the jaws; 21 were maxillary and 8 were mandibular. These keratinized odontogenic cysts were unilocular or multilocular, and some demonstrated considerable expansion resulting in bone destruction. In 13 of 29 cases, there was evidence of tooth displacement associated with the expansion of the KOC. The KOCs did not have a distinctive radiographic appearance. 48% of the cysts had a soft tissue defect through which the keratin contents could be visualized. Cyst contents ranged from hard mineralized keratin to fluid consistency with soft flecks of keratin. The pathoetiology of KOCs is unknown; however, the biological behavior is benign and thought to be slowly progressive despite potential for locally destructive growth. Recurrence is uncommon when cyst enucleation and debridement are aggressive or when solid cysts are excised en bloc.

Cystic Odontogenic Tumor with Features of Calcifying Odontogenic Cyst in 3 Cats and a Dog.

This case series describes the clinical appearance, radiographic appearance and histopathologic features of 4 patients (3 cats and 1 dog) with unique cystic oral lesions that are consistent with a diagnosis of calcifying odontogenic cyst (COC). COC is a rare odontogenic lesion in humans that has not been previously reported in companion animals. Historically, COC in humans has been classified as a benign cystic neoplasm and as a non-neoplastic odontogenic cyst. Current classification favors the latter. The cases in this series also have ambiguous features regarding classification of the lesion as an odontogenic cyst versus benign neoplasia.

Generalized Dentin Dysplasia in a Four-Year-old dog.

Dentin dysplasia is an autosomal-dominant genetic abnormality that occurs in humans and results in diffuse radiographic dental abnormalities and variable tooth discoloration due to an underlying defect in secondary dentinogenesis. This case report presents distinctive radiographic and histopathologic dental abnormalities in a dog that are consistent with generalized dentin dysplasia. These findings are similar to but not completely analogous to any specific clinical type of dentin dysplasia in humans. Grossly, the majority of the teeth in this case were discolored and most were determined to be vital. Dentin dysplasia should be included in the list of differential diagnoses of discolored teeth and notably this form of discoloration does not necessarily indicate loss of vitality.

Case Report: Amyloid-Producing Odontogenic Tumor With Pulmonary Metastasis in a Spinone Italiano-Proof of Malignant Potential.

A 1-year-old male Spinone Italiano dog was treated for an amyloid-producing odontogenic tumor on the right maxilla with a cytoreductive surgery followed by a definitive radiation protocol. Six years later, the dog presented for a new mass on the rostral mandible as well as a lung nodule without recurrence of the original maxillary tumor. Both the mandibular mass and the lung nodule were histologically confirmed to be amyloid-producing odontogenic tumor based on the appearance of sheets and cords of the odontogenic epithelium disrupted by amorphous extracellular amyloid. This case illustrates the metastatic potential for amyloid-producing odontogenic tumor in dogs and asynchronous occurrence of multiple APOTs in the oral cavity.

Presentation, Diagnostic Imaging, and Clinical Outcome of Conventional Ameloblastoma in Dogs.

A noninductive tumor of odontogenic epithelium occurs within the tooth bearing regions of the jaw in dogs and fits the conventional definition of ameloblastoma, which is distinct from, and less common than, canine acanthomatous ameloblastoma. In order to clarify the clinical and radiological features of this uncommon odontogenic tumor in dogs, we performed a retrospective study of 20 dogs that were diagnosed between 2007 and 2015. Follow-up information was obtained for 17 of 20 dogs. The study group of dogs showed no apparent age, breed, or gender predilection. Conventional ameloblastoma is typically slow growing, well demarcated, and locally destructive. Tumors most commonly occurred as a mass or focal bony swelling within the maxilla (13/20) or mandible (7/20). Based on cases with available diagnostic imaging, as either dental radiographs or computed tomographic images, the tumors were usually intraosseous and caused mixed lytic/proliferative bone changes. Nevertheless, conventional ameloblastomas did not aggressively infiltrate adjacent tissues and recurrence was not observed within the study group, even in patients with narrow surgical margins or treatment by cyst enucleation.

The canine furcation cyst, a newly defined odontogenic cyst in dogs: 20 cases (2013-2017).

OBJECTIVE: To characterize clinical, radiographic, and histologic features of canine furcation cysts (CFCs) in dogs and to propose possible mechanisms of CFC development. ANIMALS: 20 client-owned dogs with CFCs biopsied between January 1, 2013, and December 31, 2017. PROCEDURES: Medical records of the Center for Comparative Oral and Maxillofacial Pathology at the University of Wisconsin-Madison were retrospectively searched to identify records of dogs that had surgical biopsy specimens of mandibular or maxillary cavitary lesions diagnosed as odontogenic cysts and that met additional inclusion criteria. Biopsy sample submission records, medical records, clinical and radiographic images, and histologic samples were reviewed. Clinical, radiographic, and histologic features were evaluated. RESULTS: Mean body weight and age of affected dogs were 23.5 kg (51.7 lb) and 8.2 years, respectively. All 20 dogs had a unilateral cyst, with the right (n = 13) or left (7) maxillary fourth premolar tooth affected and viable in all dogs. A predominant clinical sign was a fluctuant swelling of the buccal gingiva and mucosa overlying the CFC, and enucleation of the cyst lining, with or without extraction of the affected tooth, resolved the lesion in most dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings indicated that CFC is an odontogenic cyst of uncertain etiopathogenesis and that complete evaluation of the clinical, radiographic, and histologic features of the lesion in affected patients is necessary to distinguish a CFC from other odontogenic cysts and tumors in dogs. Defining CFCs in terms of characteristic features permits accurate diagnosis and appropriate treatment of these previously unclassifiable odontogenic cysts in dogs.

Diagnosis and Treatment of an Odontogenic Epithelial Tumor in a Dog With Features of Squamous Odontogenic Tumor.

A 9-year-old standard poodle presented for a comprehensive oral health assessment and treatment, at which time a left rostral mandibular swelling was recognized. The mass was biopsied and eventually excised by a left rostral mandibulectomy en bloc resection. Histopathology supported the diagnosis of a benign, intraosseous, epithelial tumor that was otherwise unclassified. The clinical, radiological, and histological features of this case are similar to those reported for squamous odontogenic tumor (SOT) in humans. This case study relays the diagnosis, treatment, and follow-up of the first SOT-like tumor in a dog.

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.

Aortic tear and dissection related to connective tissues abnormalities resembling Marfan syndrome in a Great Dane.

Aortic tears and acute aortic dissection are rarely reported in dogs. This report describes a case of aortic dissection and probable sinus of Valsalva rupture in a young Great Dane with associated histopathologic findings suggestive of a connective tissue abnormality.

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.

Nomenclature and Classification of Odontogenic Tumors - Part II: Clarification of Specific Nomenclature.

Accurate identification of odontogenic tumors is critical for productive communication and an important foundation for useful comparative epidemiologic studies of odontogenic tumors in both domestic animals and humans. This manuscript illuminates the subject of veterinary odontogenic tumor nomenclature and will serve as a foundation for future updates in nomenclature and classification of odontogenic tumors.

Nomenclature and Classification of Odontogenic Tumors - Part I: Historical Review.

Odontogenic tumor nomenclature and classification is frustrating for both physicians and veterinarians. There has been and continues to be an evolution of the terms and taxonomy used in veterinary and human literature. In this historical review, we aim to provide veterinarians a fundamental basis for understanding how the etymology for odontogenic tumors has evolved over the past two centuries.

Septic implantation syndrome in dogs and cats: a distinct pattern of endophthalmitis with lenticular abscess.

OBJECTIVE: To summarize the clinical and pathologic findings in a group of dogs and cats with progressive clinical ocular disease, which were diagnosed with suppurative endophthalmitis and lens capsule rupture. ANIMALS STUDIED: Twenty cats and forty-six dogs that underwent unilateral enucleation or evisceration for intractable uveitis and/or glaucoma. PROCEDURE: Biopsy submission requests and microscopic case material were evaluated for clinical and histological features, including history of ocular trauma, duration of ocular disease, pattern of inflammation, and the presence of intralenticular microorganisms. RESULTS: The median duration for cats and dogs was 6 and 5 weeks, respectively. A history of trauma was reported for four (20%) cats and 18 (39%) dogs. All confirmed cases of trauma-three in cats and 14 in dogs-were caused by a cat scratch. Microscopically, all cases had suppurative endophthalmitis centered on the lens, lens capsule rupture, cataract, and lenticular abscess. Infectious organisms were identified by Gram stain within the lens of 14 (70%) cats and 30 (65%) dogs. Gram-positive cocci were seen most commonly. Male cats were overrepresented as compared to females. There were no apparent gender, age or breed predilections in dogs. CONCLUSIONS: A unique pattern of slowly progressive or delayed-onset endophthalmitis with lens capsule rupture, lenticular abscess, and frequently intralenticular microorganisms is associated with traumatic penetration of the globe and lens capsule. The term Septic Implantation Syndrome (SIS) is favored in lieu of 'phacoclastic uveitis' to avoid confusion with phacolytic uveitis and to clearly implicate the role of intralenticular microorganisms in the pathogenesis.