Supernumerary Incisors in CB6F1 Mice Conditioned with Chemotherapy and Total Body Irradiation before Bone Marrow Transplantation.

Multiple adult female CB6F1 mice presented with supernumerary incisors after preconditioning with chemotherapy and total body irradiation for bone marrow transplantation (BMT). Mice received nonmyeloablative total body irradiation (3 Gy) and either cyclophosphamide or bendamustine, followed by BMT and posttransplantation cyclophosphamide or bendamustine. Here we describe the clinical presentation, µCT findings, and histopathologic evaluation of the affected mice. These analyses confirmed the gross diagnosis and revealed details of the abnormal tooth morphology. We surmise that the combination of total body irradiation and chemotherapy resulted in the abnormal formation of supernumerary incisors. Supernumerary teeth should be considered as a potential confounding factor in tracking weight loss after BMT. These conditions can be managed to allow animals to reach their intended scientific endpoint.

Caries, Periodontal Disease, Supernumerary Teeth and Other Dental Disorders in Swedish Wild Boar (Sus scrofa).

Between January and December 2013, the dental and periodontal health of 99 Swedish wild boars (Sus scrofa) was investigated. Sampling occurred in conjunction with routine hunting at six large estates in the southern and middle parts of Sweden. All six of the estates use supplemental feeding. The weight of the animals, their sex and their dates of death were noted. Age was estimated using tooth eruption and tooth replacement patterns. The oral cavity was inspected and abnormalities were recorded on a dental chart modified for wild boars. The findings included supernumerary teeth, absence of teeth, mild class II malocclusion, severe tooth wear, periodontitis, calculus, caries, tooth fractures and the presence of enamel defects. Swedish wild boars suffer from different dental lesions and the impact of supplemental feeding on dental and periodontal health is still to be investigated.

Oral examination and radiographic evaluation of the dentition in wild cats from Namibia.

Feline tooth resorption has been widely reported in domestic cats and sporadically described in other felidae. The goal of the present study was to determine the prevalence of tooth resorption and to report other dental problems in a population of wild felidae. Observations of dental disorders and anomalies were made in skulls from 73 wild felidae (cheetahs, leopards, caracals, African wildcats, and lions) originating from Namibia. In addition, radiographs were taken in 43 cases to determine signs of bone and root pathology. Radiographs showed varying stages of tooth resorption in 16.0% of the specimens. Other dental anomalies found included fused teeth, supernumerary roots, or missing teeth. The prevalence of dental resorption in wild felidae was lower than reported in the domestic cat.

Endoscopic removal of a molariform supernumerary intranasal tooth (heterotopic polyodontia) in a horse.

CASE DESCRIPTION: A 3-year-old Thoroughbred mare was evaluated because of abnormal upper respiratory tract sounds (that had become apparent during race training) of 3 to 4 months' duration. CLINICAL FINDINGS: On initial physical evaluation, there were no abnormal findings. During trotting, an abnormal upper airway expiratory sound was audible. Endoscopic examination revealed a small mass protruding into the right ventral nasal meatus. Radiographic images of the skull revealed no abnormal findings. Computed tomography of the head revealed an abnormal structure in the same location as the mass that was observed during endoscopy. The x-ray attenuation of the mass was identical to that of dental tissue. TREATMENT AND OUTCOME: The mass was surgically removed with endoscopic guidance. On gross examination, the excised mass appeared to be a nearly normal molariform tooth. Histologic examination revealed that it was a well-formed tooth, with no other associated cellular populations. The mass was determined to be a molariform supernumerary intranasal tooth. Six months following discharge from the hospital, the trainer reported that the abnormal respiratory tract sound was no longer audible. During a follow-up endoscopic examination performed at the training facility, no abnormalities were detected. CLINICAL RELEVANCE: In horses, an intranasal tooth should be considered as a differential diagnosis for expiratory stridor. Clear definitions of heterotopic polyodontia, dentigerous cyst, and temporal teratoma can be used to clinically diagnose these separate anomalies. In the horse of this report, computed tomographic findings contributed to determination of a diagnosis and formulation of a treatment plan.

Analysis of dental anomalies in the Siberian mole, Talpa altaica (Insectivora, Talpidae).

We re-examined tooth variation in specimens of the Siberian mole, Talpa altaica, from the collection of the Siberian Zoological Museum and discuss the mechanisms of dental evolution. The number of teeth counted in 1789 specimens ranged from 34 to 47, and supernumerary, absent, and connate teeth were observed. The most frequent tooth anomaly was an absent tooth in the premolar region (200 maxillary first premolars and 190 mandibular third premolars), which does not support Fujita and Kirino's terminal reduction hypothesis in the mandible [Fujita T, Kirino T. Ha No Kaibougaku. 21st ed. Tokyo: Kanehara Publishers Inc.; 1976 (in Japanese)]. Supernumerary teeth were found in premolar rows and in the incisor and molar regions. An maxillary fourth molar, positioned distal to the normal third molar, was thought to result from a genetically programmed atavistic event during the natal stages. Connate teeth were observed only in the premolar rows and were thought to have developed with the fusion of two independent tooth germs. Connate premolars appeared to result from an expression of an incomplete division of tooth germ at an early developmental stage or a reunion of independent tooth germs, based on the morphological similarity of the normal and supernumerary premolars. These extraordinarily frequent tooth anomalies of T. altaica are of much interest both in terms of tooth development and classification.

Supernumerary cheek teeth (n = 24): clinical features, diagnosis, treatment and outcome in 15 horses.

REASONS FOR PERFORMING STUDY: There are few reports of case series of horses with supernumerary cheek teeth (SCT) that document clinical findings, treatment and long-term outcome. OBJECTIVES: To review the clinical and ancillary diagnostic findings and responses to different treatments in horses with SCT. METHODS: The case records of 15 horses were reviewed and long-term outcomes obtained by telephone interview. RESULTS: Fifteen horses with a total of 24 SCT were identified. Two SCT were incidental findings and were not treated. Clinical signs were improved or resolved in 11 of 13 of the teeth treated conservatively and all 6 treated by extraction had a favourable outcome. Four horses were subjected to euthanasia within a short period of diagnosis, either due to a poor prognosis at the outset or failure to respond to initial conservative treatment. CONCLUSIONS: Some SCT are chance findings and do not cause clinical signs. In those instances where clinical signs of dental disease are mild, conservative treatment including the management of diastema and reduction of overgrowths is often effective. Horses with severe clinical signs attributable to an SCT are likely to require extraction of the offending tooth. POTENTIAL RELEVANCE: An SCT is an uncommon dental anomaly but should be considered in the differential diagnosis of cases with signs of severe dental disease. The preferred management for SCT is very variable and determined by the severity of the associated changes, but ranges from conservative measures through forceps extraction per os to major facial flap surgery.

Variations in the number of teeth in wild Japanese serow (Naemorhedus crispus).

Skulls of 755 Japanese serow (Naemorhedus crispus) were examined for numerical anomalies of teeth, and these were found in 30 (4.0%) specimens. In addition to supernumerary and congenital missing teeth, embedded teeth were also identified. Supernumerary teeth were found in 10 (1.3%) specimens, congenital missing teeth were found in nine (1.2%) specimens, and embedded teeth were found in 11 (1.5%) specimens. Supernumerary teeth were found among the incisors, the upper and lower premolars, and the lower molars. Based on the appearance of certain tooth classes, their size, and their form, atavism was considered to be a possible cause of the occurrence of some of these teeth. Congenital missing teeth were found at the loci of the lower incisors, canines and P(2). In Japanese serow, there appeared to be a tendency for congenitally missing P(2) as well as P(1). All embedded teeth were found at the locus of P(2). These teeth may have occurred as an intermediate state between normal and congenital missing teeth. Variations in the number of teeth in Japanese serow were concordant with their phylogenetic background. Moreover, although variations in the number of cheek teeth tended to be concentrated in the mesial region of the premolars, the tendency in the incisive region was for teeth to appear mesial as well as distal within an incisor-tooth sequence. These results, which are not in accordance with terminal reduction theory, indicate that the phenomenon of tooth degeneration does not only occur at the end of a tooth row.

A review of equine dental disorders.

Equine dentistry is a very important but until recently rather neglected area of equine practice, with many horses suffering from undiagnosed, painful dental disorders. A thorough clinical examination using a full mouth speculum is a pre-requisite to performing any equine dental procedure. Common incisor disorders include: prolonged retention of deciduous incisors, supernumerary incisors and overjet--the latter usually accompanied by cheek teeth (CT) overgrowths. Overjet can be surgically corrected, but perhaps should not be in breeding animals. In younger horses, traumatically fractured incisors with pulpar exposure may survive by laying down tertiary dentine. Loss or maleruption of incisors can cause uneven occlusal wear that can affect mastication. Idiopathic fractures and apical infection of incisors are rare. The main disorder of canine teeth is the development of calculus of the lower canines, and occasionally, developmental displacements and traumatic fractures. The main indications for extraction of "wolf teeth" (Triadan 05s) are the presence of displaced or enlarged wolf teeth, or their presence in the mandible. Developmental abnormalities of the CT include; rostral positioning of the upper CT rows in relation to the lower CT rows--with resultant development of focal overgrowths on the upper 06s and the lower 11s. Displaced CT develop overgrowths on unopposed aspects of the teeth and also develop periodontal disease in the inevitable abnormal spaces (diastemata) that are present between displaced and normal teeth. Diastemata of the CT due to excessive developmental spacing between the CT or to inadequate compression of the CT rows is a common but under diagnosed problem in many horses and causes very painful periodontal disease and quidding. Supernumerary CT mainly occur at the caudal aspect of the CT rows and periodontal disease commonly occurs around these teeth. Eruption disorders of CT include prolonged retention of remnants of deciduous CT ("caps") and vertical impaction of erupting CT that may lead to large eruption cysts and possibly then to apical infections. Disorders of wear, especially enamel overgrowths ("enamel points"), are the main equine dental disorder and are believed to be largely due to the dietary alterations associated with domestication. If untreated, such disorders will eventually lead to more severe CT disorders such as shearmouth and also to widespread periodontal disease. More focal dental overgrowths will develop opposite any CT not in full opposition to their counterpart, e.g., following maleruption of or loss of a CT. Because of the great length of reserve crown in young (hypsodont) CT, apical infections usually cause infection of the supporting bones and depending on the CT involved, cause facial swellings and fistulae and possibly sinusitis. Diagnosis of apical infection requires radiography, and possibly scintigraphy and other advanced imaging techniques in some early cases. When possible, oral extraction of affected CT is advocated, because it reduces the costs and risks of general anaesthesia and has much less post-extraction sequelae than CT repulsion or buccotomy.

Equine dental disease part 2: a long-term study of 400 cases: disorders of development and eruption and variations in position of the cheek teeth.

Of 400 referred horses with dental disorders, 349 cases suffered from primary disorders of their cheek teeth, ninety of these from disorders of development or eruption, or displacements. These included 20 cases with rostral maxillary and caudal mandibular cheek teeth overgrowths, 16 with diastemata, 15 with grossly enlarged mandibular 'eruption cysts', 4 with grossly enlarged maxillary cheek teeth 'eruption cysts', 10 cases with supernumerary cheek teeth and 23 cases with displaced cheek teeth. These displacements were believed to be developmental in 16 cases and acquired in the remaining 7 cases. Long-term response to treatments, that included removal of overgrowths and extraction of teeth with deep secondary periodontal disease was excellent for most disorders except diastemata.

Mandibular canine tooth impaction in a young dog--treatment and subsequent eruption: a case report.

Extraction of an embedded supranumerary incisor tooth and surgical exposure of the crown of an impacted left mandibular canine tooth were performed in a 5 month-old Doberman Pinscher dog. Six months following surgery, the canine tooth was fully erupted and in normal occlusion. A review of tooth eruption in the dog is provided.

Congenital dental disease of horses.

Equine congenital dental deformities are not limited merely to those presented here; however, the examples discussed offer the reader an appreciation for the range of severity and complexity that may be found in affected horses. The veterinarian is obligated to provide the best possible care for the patient and to relieve animal suffering. The lack of definitive evidence for heritability of many of these defects can place the veterinarian in an untenable position, particularly when presented with literature that proclaims or suggests without evidence that a particular condition is inherited. In such cases, the veterinarian is encouraged to counsel owners, citing substantiated medical information, and to recommend that owners make the decision to eliminate the affected animals' ability to reproduce.

The dental pathology of feral cats on Marion Island, part I: congenital, developmental and traumatic abnormalities.

Skulls (n = 301) of adult feral cats from Marion Island, a sub-Antarctic island, were examined macroscopically. Congenital anomalies, which were rare, included a few supernumerary premolars, located mesially to those normally present. Supernumerary roots, mainly of the maxillary third premolar, were found in just over 10% of cases. The maxillary second premolar was absent in 16.8% of skulls; dichotomous and double-formed roots of this tooth were present in 20.1% and 1.9% of cases, respectively. Enamel hypoplasia, which is most unusual in this species, was noted in 24.6% of cases, and persistent deciduous teeth in 2.0%. Dental abrasion, which was noted in 19.3% of cats, affected only 2.3% of teeth, most commonly the lower fourth and upper third premolars. Dental fractures, mainly complicated crown fractures and root fractures, were noted in 54.8% of cats and 7.0% of teeth. Fractures were found most commonly in the canine and carnassial teeth, as also were periapical lesions, which were often severe. Mandibular fractures in various stages of healing were found in 11 cats (3.7%); such fractures most frequently affected the body of the mandible and resulted in malunion. It was concluded that the high prevalence of dental fractures and associated periapical lesions probably exerted a significant adverse effect on health and survival in this population of feral cats.

[Polyodontia and abnormal forms of teeth in dogs (author's transl)]. / Polydontie en afwijkende tandvormen bij de hond.

Polyodontia was observed in forty-seven (13 per cent) out of 373 dogs studied. These forty-seven dogs with polyodontia included sixteen Boxers. The supernumerary tooth was situated in the proximity of the first premolar in the maxilla in thirty-two dogs. The following abnormal forms were observed among the teeth of the dogs: dichotomy of an incisor in a Fox Terrier and a Great Dane, a pair of geminate teeth at the site of the first mandibular premolar in a Rottweiler and a fused premolar near the first maxillary premolar in a Boxer. The possible pathogenesis of polyodontia and abnormal tooth forms is discussed.