The prevalence of secondary dentinal lesions in cheek teeth from horses with clinical signs of pulpitis compared to controls

Reasons for performing study: With the advent of detailed oral examination in horses using dental mirrors and rigid endoscopy, secondary dentinal lesions are observed more frequently. More information regarding the association of secondary dentinal defects with apical dental disease would improve the sensitivity of oral examination as a diagnostic aid for pulpitis. Objectives: To assess prevalence and severity of secondary dentinal defects observed on examination of occlusal surfaces of cheek teeth (CT) from horses showing clinical signs of pulpitis compared to asymptomatic controls. Methods: Records from all cases of equine CT exodontia at the University of Bristol over a 4 year period were examined. Case selection criteria included the presence of clinical signs of pulpitis, an intact extracted tooth and availability of a complete history and follow up. Cases where coronal fracture or periodontal pocketing featured were excluded. CT from cadavers with no history of dental disease served as normal controls. Triadan positions and eruption ages of control teeth were matched with those of teeth extracted from cases. CT from selected cases and control teeth were examined occlusally. Secondary dentinal defects were identified and graded. Prevalence of occlusal lesions in CT with pulpitis and controls was compared. Results: From the records of 120 horses where exodontia was performed, 40 cases matched selection criteria. Twenty‐three mandibular and 21 maxillary CT were extracted from cases. The controls consisted of 60 mandibular and 60 maxillary CT from 7 cadaver skulls. Secondary dentinal defects were significantly over‐represented in CT extracted from cases of pulpitis (P<0.001). Of diseased mandibular CT, 56.5% had defects compared to none of the controls. Of diseased maxillary CT, 57% had defects compared with 1.6% of controls. Multiple defective secondary dentinal areas and severe lesions were more prevalent in diseased mandibular CT compared with diseased maxillary CT. Conclusions and practical significance: Careful examination of occlusal secondary dentine is an essential component in investigation of suspected pulpitis in equine CT.     

Dental diastemata and periodontal disease secondary to axially rotated maxillary cheek teeth in three horses

Malerupted axially rotated maxillary cheek teeth (CT) were identified as the primary cause of diastemata and severe periodontitis in 3 horses. Diastema widening and periodontal debridement was performed initially in one case but did not resolve clinical signs. Subsequently, all 3 cases underwent extraction of the axially rotated teeth per os without complication. Follow‐up indicated remission of periodontitis and signs of oral pain. In these cases, maxillary CT had erupted in a manner that resulted in axial rotation of CT with undulating buccal and palatal surfaces aligned with the interproximal surfaces of adjacent normally orientated teeth. This resulted in poor interproximal compression and diastemata causing severe periodontitis. Axially rotated maxillary CT and the severe periodontitis that they precipitate, have not been previously described as a discrete dental disease entity.     

Equine idiopathic cheek teeth fractures: part 3: a hospital-based survey of 68 referred horses (1999-2005)

REASONS FOR PERFORMING STUDY: There is limited information available on the more serious sequellae of idiopathic cheek teeth (CT) fractures. OBJECTIVES: To obtain information on clinical and ancillary diagnostic findings in referred horses with idiopathic CT fractures. METHODS: Details of all horses suffering from idiopathic CT fractures referred to the Equine Hospital at the University of Edinburgh 1999-2005 were examined, and information concerning fracture patterns, clinical and ancillary diagnostic findings, treatments and long-term response to treatments were obtained and analysed. RESULTS: A total of 60 maxillary and 17 mandibular idiopathic CT fractures were diagnosed in 68 horses. Fracture patterns included maxillary CT lateral slab fractures (45%), maxillary CT midline sagittal fractures (16%) and various other patterns of maxillary CT fractures (17%). In the mandibular CT, lateral slab fractures were found (12%) and various other CT fracture patterns were present in 10%. The more centrally positioned CT (maxillary and mandibular Triadan 08s and 09) were preferentially fractured. Clinical signs included quidding in 47% of cases; bitting and behavioural problems (28%); signs of apical infection, including bony swellings and nasal discharge (21%); anorexia/weight loss (15%); halitosis (13%); and buccal food impaction (12%). The treatment of all cases was conservative whenever possible and included corrective rasping of the remaining tooth (46% of cases); oral extraction of the smaller and loose dental fragment (32%) and extraction of the entire fractured tooth by oral extraction (28%) or by repulsion (13%). Prophylactic treatment of adjacent, nonfractured CT with carious infundibula was possibly of value in preventing further midline sagittal maxillary CT fractures. CONCLUSIONS: Horses referred with idiopathic CT fractures frequently have clinical signs of apical infection of the fractured CT and these teeth require extraction, orally if possible. More conservative treatment of idiopathic CT fractures without signs of gross apical infection can resolve clinical signs in most cases. POTENTIAL RELEVANCE: In the absence of apical infection, extraction of only the loose dental fragments of CT with idiopathic fractures is usually successful.     

CT FEATURES OF ALVEOLITIS AND SINUSITIS IN HORSES

Sinusitis is a common disorder in horses and may result from trauma, dental diseases, or space-occupying lesions. Radiography can only provide a limited amount of information. Computed tomography (CT) has been documented as an alternative imaging method. Eighteen horses (mostly Warmblood) with signs of chronic sinusitis were examined preoperatively with CT to assist in diagnosis of the underlying cause. There was a group of common CT features in horses with dental disease and sinusitis. The first molar was the most frequently affected maxillary cheek tooth. Hypoattenuation of the cementum, destruction of the enamel, and filling of the infundibular cavity with gas were the most frequent CT findings associated with caries. Gas bubbles within the bulging root area or fragmentation of the root in combination with swelling of the adjacent sinus lining were the most important CT features of dental decay. CT findings associated with sinusitis included excessive thickening of the respiratory epithelium in the rostral maxillary sinus; the caudal maxillary sinus was less often involved. The infraorbital canal, the nasomaxillary duct, and the frontomaxillary aperture were usually involved. The maxillary bone, however, especially the facial crest, was involved in nearly every horse, being characterized by endosteal sclerosis, thickening, periosteal reaction, and deformation leading to facial swelling in chronic infections. CT images allowed identification of involvement of individual teeth more clearly to reveal the diseased one for treatment. Three-dimensional imaging allowed improved understanding of the extent and severity of the pathologic change.     

Long-term Outcome of Tooth Repulsion in Horses A Retrospective Study of 61 Cases

The records of 61 horses undergoing tooth repulsion for treatment of alveolar periostitis were reviewed. Seventeen of 36 horses (47%) in which maxillary teeth were removed had serious postoperative complications, such as infection of a second tooth, bone sequestration, chronic sinusitis, draining tracts, retained dental packing, feed impaction of the alveolus or sinus, suture-line dehiscence, or skin-flap sloughs. Eight horses required at least one additional surgical procedure. Eight of 25 horses (32%) in which mandibular teeth were removed had serious postoperative complications, and four horses required an additional surgical procedure. Hospitalization lasted 2 to 61 days (median, 22 days) for maxillary teeth and 3 to 35 days (median, 8 days) for mandibular teeth. Long-term follow-up (at least 5 months) was possible in 47 horses. Twenty-four of 30 horses (80%) with maxillary tooth repulsion healed without further problems; six horses had persistent nasal discharge. Fourteen of 17 horses (82%) with mandibular tooth repulsion healed with no further problems or with only minor complications; three horses had a chronic draining tract.     

Prevalence and some clinical characteristics of equine cheek teeth diastemata in 471 horses examined in a UK first-opinion equine practice (2008 to 2009)

Cheek teeth (CT) diastemata are now recognised as a clinically significant equine disorder, but their prevalence in the general equine population is unknown. There is also limited information on the signalment of affected horses; the more commonly affected Triadan sites; and the shape and clinical characteristics of CT diastemata. During the 12-month study period (2008 to 2009), standardised records were obtained during routine dental examinations performed by five veterinarians in a first-opinion equine practice. Cheek teeth diastemata were identified in 49.9 per cent of all horses (n=471) of mean age 11 years (range one to 30 years), with 83.5 per cent of all diastemata affecting mandibular CT and 16.5 per cent affecting maxillary CT. The mean number of diastemata per case was 1.7 (range one to 20) and the mandibular 07 to 08 position was most commonly affected. Valve diastemata were more common (72.1 per cent prevalence) than open diastemata (27.9 per cent). Food trapping was present in 91.4 per cent of diastemata, with gingivitis and periodontal pockets adjacent to 34.2 per cent and 43.7 per cent, respectively. Halitosis was present in 45.5 per cent of affected horses. There was an age-related increase in both the prevalence of diastemata, and in the numbers of diastemata per affected horse, and horses over 15 years old had a significantly increased proportion of open diastemata.     

Maxillary odontogenic myxoma in young horses: Six cases (2003–2011)

Six young horses presented with a rapidly expanding maxillary mass with concurrent nasal discharge. All horses had a nonpainful firm unilateral facial swelling centred over the maxillary sinuses, accompanied by mucopurulent nasal discharge. Diagnostic imaging revealed an infiltrative nasomaxillary mass with cheek tooth involvement, diagnosed as odontogenic myxoma. The tooth involvement included missing, malformed and/or displaced dental precursors or unerupted teeth. Due to the rapid expansion and extent of the masses, and the poor prognosis reported for surgical excision, euthanasia was recommended and performed in all cases. Macroscopically, a soft oedematous tissue with a grey to green colour was seen in the regions of missing, malformed or displaced dental precursors or unerupted teeth. Histologically, this tissue consisted of spindle shaped cells surrounded by an abundant homogenous pale stroma, rich in acid mucopolysaccharides. Immunohistochemistry was positive for actin and the mesenchymal marker vimentin. The cheek tooth involvement identified in the described cases resembled what is previously reported in odontogenic myxoma in children and young adults. Even in man, maxillary odontogenic myxoma represents a therapeutic challenge due to the invasiveness of the lesions and radical surgical excision is recommended. Treatment is further complicated by sinonasal involvement. Surgery was not attempted in the cases presented here due to the extent of the lesions and the risk of recurrence. Clinicians should be aware of this rare condition when presented with young horses with sinonasal neoplasia.     

Occlusal fissures of the equine cheek tooth: Prevalence,location and association with disease in 91 horses referred for dental investigation

Reason for performing study: Fissures of the occlusal surface of the equine cheek tooth are poorly understood and their association with dental disease is unknown. Objective: To describe the prevalence and location of occlusal fissures in the cheek teeth (CT) of a group of horses referred for dental investigation/treatment, and determine association with intercurrent dental disease. Methods: Digital video recordings of oral endoscopic examinations for all horses referred to the Rossdales Equine Hospital for dental investigation from November 2006 to June 2009 were reviewed. Location of occlusal fissures in relation to both Triadan tooth position and pulpar secondary dentine was recorded; direction of fissure and concurrent involvement of enamel was also documented. The CT location considered at the time of examination to be the primary site/s of disease was correlated with presence of fissures on these teeth. Results: 91 cases meeting the inclusion criteria were identified. Occlusal fissures were documented in 58.2% (53/91) cases, with a total of 227 CT being affected. Fissures were most prevalent mid‐arcade. The majority (92.1%) of fissures in maxillary CT were associated with the caudal palatal pulp horn. Fissures in mandibular CT were predominantly associated with the buccal pulp horns (95.7%). There was no significant difference in the median number of CT with fissures in relation to gender. There was no correlation between age (r²= 0.01) of horse and number of CT with fissures. A significantly greater number of CT with multiple occlusal fissures was found in mandibular compared to maxillary arcades. No correlation was found between presence of fissures and location of individual CT considered to be primarily responsible for presentation. Conclusions: Occlusal fissures in this group of animals were common and not correlated to primary site of dental disease. Potential relevance: In horses subjected to dental investigation, occlusal fissures of the cheek teeth should not be considered an indicator of tooth compromise. Location and direction of fissure propagation in most cases is inconsistent with occlusal fissures being causally implicated in slab fractures of cheek teeth, although site predilection may indicate a possible association with masticatory forces.     

Equine idiopathic cheek teeth fractures: part 2: a practice-based survey of 147 affected horses in Britain and Ireland

REASONS FOR PERFORMING STUDY: There is limited information on the prevalence of idiopathic cheek teeth (CT) fractures in the general equine population and on which CT are most commonly affected. OBJECTIVES: To obtain information on the prevalence of fracture patterns and clinical details of idiopathic CT fractures. METHODS: Details of cases with idiopathic CT fractures encountered were obtained via a questionnaire sent to suitably experienced veterinary practitioners and equine dental technicians (EDTs). RESULTS: Details of 147 horses that suffered a total of 182 idiopathic CT fractures; and median 0.4% (range 0.07-5.9%) of horses examined were diagnosed with such fractures; 133 maxillary CT and 49 mandibular CT fractures were found; maxillary Triadan 09s and 10s were preferentially fractured (46% of all fractured CT); fracture patterns included maxillary CT slab fractures (through 1st and 2nd pulp chambers) in 87 teeth (48% of all fractured CT), maxillary CT midline sagittal fractures (through the infundibula) in 31 CT; and various other types of maxillary CT fractures in 15 CT. In the mandibular CT, lateral slab fractures (through the 4th and 5th pulp chambers) were found in 28 CT and a variety of other fracture patterns in the other 21 mandibular CT. Clinical signs included quidding in 33% of cases, bitting and behavioural problems (29%) and halitosis (12%), however 39% of horses with idiopathic CT fractures were asymptomatic. Treatments included oral extraction of the smaller dental fragment in 37% of cases, extraction of the entire fractured tooth (9%); removal of sharp edges on the remaining part of fractured tooth (14%); reduction of height of the opposite tooth (4%); other surgical or endodontic treatments, or referral of case for further investigation and treatment (10%); or no specific treatment (39%). Following treatment, 81% of cases were reported to be asymptomatic, 6% had ongoing clinical problems and the outcome was unclear in 13% of cases. CONCLUSIONS: Idiopathic CT fractures are present in approximately 0.4% of horses and may variably cause none to severe clinical signs. Most idiopathic CT fractures respond well to treatment. POTENTIAL RELEVANCE: Understanding of the prevalence, clinical findings and treatment of idiopathic CT fractures will improve management of these disorders.     

Equine dental disease part 4: a long-term study of 400 cases: apical infections of cheek teeth

Of 400 horses referred because of equine dental disease, 162 suffered from primary apical infections of their cheek teeth (CT), including 92 with maxillary CT infections and 70 with mandibular CT infections. Maxillary swellings and sinus tracts were more common (82 and 26% incidence, respectively) with infections of the rostral 3 maxillary CT, than with infections of the caudal 3 maxillary CT (39 and 5% incidence, respectively). Nasal discharge was more commonly present with caudal (95%) than rostral (23%) maxillary CT infections. Mandibular CT apical infections commonly had mandibular swellings (91%) and mandibular sinus tracts (59%) and these infections were closely related to eruption of the affected CT. A variety of treatments, including medical treatment, apical curettage, repulsion and oral extraction of affected teeth were utilised in these cases, with oral extraction appearing to be most satisfactory. Infections of caudal maxillary CT with a secondary paranasal sinusitis were most refractory to treatment, with a complete response to the initial treatment achieved in just 33% of these cases. Most other cases responded fully to their initial treatment. The long-term response to treatment was good in most cases.     

Extraction of 22 equine cheek teeth with displaced sagittal fractures using polymethylmethacrylate stabilisation (2011–2016)

Displaced sagittal cheek tooth fractures are a cause of oral pain, quidding and apical infection. Intraoral extraction is the preferred technique to remove affected teeth, but can be difficult due to displaced and friable fracture fragments. Stabilising fracture fragments via filling of the fracture space with polymethymethacrylate (PMMA) prior to removal may be a useful method to facilitate intraoral extraction. Case details were examined retrospectively. A total of 22 cheek teeth required extraction in 20 horses because of displaced sagittal fractures. Clinical diagnoses were made using oral examination, oral endoscopy, skull radiography and computed tomography. All procedures were performed in standing, sedated horses in stocks. Fracture spaces were cleaned and packed with PMMA and teeth removed using a routine intraoral extraction technique. Digital photographs of extracted teeth were taken and tooth measurements calibrated using digital image software. Intraoperative difficulties, as well as post-operative complications were recorded. A total of 21 maxillary and one mandibular cheek teeth were extracted. All maxillary teeth had advanced infundibular caries. Intraoral extraction was successful in 16 cases; six were unsuccessful and required repulsion due to tooth fragmentation or abnormal dental anatomy. In 11 cases, maxillary or conchofrontal sinus trephination was performed to either treat sinusitis, repulse the tooth, or both. Two horses developed short-term complications following local anaesthesia of the maxillary nerve. The mean ratio of fracture depth to tooth length was 0.59 and mean ratio of fracture width to tooth width 0.53. The limitations of the study are its small sample size, retrospective nature and lack of control group to compare extraction success in PMMA and non-PMMA groups. It was concluded that using PMMA to stabilise displaced sagittal fractures in equine cheek teeth is a simple, effective method of facilitating intraoral extraction and may reduce the need for more invasive procedures.     

Equine odontogenic tumors: Clinical presentation,CT findings,and outcome in 11 horses

Odontogenic tumors present as locally invasive, slow growing, firm swellings on the face. They are rare in all species and are characterized histologically by the degree of differentiation and dental tissue of origin. Radiographic appearance is not pathognomonic for these lesions. Computed tomographic (CT) examination allows exact determination of tumor extension and aggressiveness. The objectives of this retrospective, case series study were to describe the clinical presentation, CT characteristics, and outcome in horses with histologically confirmed odontogenic tumors, and to identify imaging features suggestive of individual types of tumors. Four ameloblastomas, two ameloblastic carcinomas, three ameloblastic fibromas, and two complex odontomas were included. All but one complex odontoma presented as a single mass. All tumors were associated with maxillary or mandibular bone expansion, alveolar and cortical bone lysis, and cortical bone thinning. The majority also had cortical bone thickening and periosteal proliferation. All tumors contained some degree of mineral attenuation, although only the complex odontomas contained enamel attenuation allowing differentiation from other types of odontogenic tumors in this study. Ameloblastomas were found to have variable CT characteristics likely due to the sub‐groups of ameloblastomas. Both ameloblastic carcinomas contained a mixture of mineralized and soft tissue attenuating material whereas ameloblastic fibromas were mainly composed of soft tissue attenuating material. Computed tomographic characteristics of odontogenic tumors generally indicate that they are expansile, aggressive tumors and can occur in a wide range of ages. Further investigation is needed to elucidate differences between each type of equine odontogenic tumor.     

The incidence and distribution of peripheral caries in the cheek teeth of horses and its association with diastemata and gingival recession

Although considered relatively common in horses, there is little information on the prevalence, distribution and aetiology of peripheral caries of the equine cheek teeth (CT). The objective of this study was to investigate a possible association between this lesion and diastemata or 'gaps' between the CT which facilitate the entrapment of food material. Video recordings of oroscopic examinations of all dental cases at an equine hospital over a 3-year period were reviewed, and the location of all diastemata, peripheral caries, trapped food, and of gingival recession were recorded. A total of 108 cases met study inclusion criteria and 298 diastemata and 445 CT with peripheral caries were noted. Diastemata were found predominantly in the mandibular arcades (80%) and 75% of animals had at least one diastema. Peripheral caries was uniformly distributed between the maxillary and mandibular CT, being most prevalent on the most caudal three teeth (87%). Overall, diastemata were not associated with peripheral caries at either a tooth or individual patient level. However, a highly significant association was found between the presence of trapped food within diastemata and gingival recession.     

Donkey dental anatomy. Part 2: Histological and scanning electron microscopic examinations

Ten normal cheek teeth (CT) were extracted at post mortem from donkeys that died or were euthanased for humane reasons. Decalcified histology was performed on three sections (sub-occlusal, mid-tooth and pre-apical) of each tooth, and undecalcified histology undertaken on sub-occlusal sections of the same teeth. The normal histological anatomy of primary, regular and irregular secondary dentine was found to be similar to that of the horse, with no tertiary dentine present. Undecalcified histology demonstrated the normal enamel histology, including the presence of enamel spindles. Scanning electron microscopy was performed on mid-tooth sections of five maxillary CT, five mandibular CT and two incisors. The ultrastructural anatomy of primary and secondary dentine, and equine enamel types-1, -2 and -3 (as described in horses) were identified in donkey teeth. Histological and ultrastructural donkey dental anatomy was found to be very similar to equine dental anatomy with only a few quantitative differences observed.     

RADIOGRAPHY AND COMPUTED TOMOGRAPHY IN THE DIAGNOSIS OF NONNEOPLASTIC EQUINE MANDIBULAR DISEASE

We compared the information gained from computed tomography (CT) vs. radiography in horses with nonneoplastic disease of the mandible. We hypothesized that CT would provide additional diagnostic information. Medical records, radiographs, and CT images of horses with nonneoplastic mandibular disease evaluated between 1994 and 2008 were reviewed. Nineteen horses were identified; 11 had a tooth root abscess and related disease, four had a fracture of the teeth and/or mandible, and four had a nonneoplastic mass. Both CT images and radiographs allowed identification of diseased teeth that appeared clinically normal otherwise. CT allowed identification of teeth that were clinically affected but appeared normal radiographically. Parameters such as tooth pulp involvement, lamina dura destruction, presence of bone fragments, lingual and buccal mandibular bone periosteal reaction, and cortical bone destruction were more conspicuous with CT. Performing radiography and CT in horses with nonneoplastic mandibular disease provides a more complete evaluation than either technique alone. CT contributes additional information that could otherwise be overlooked with radiographs alone in horses with a mandibular fracture. CT provides ancillary information to radiographs in horses with dental infection or a nonneoplastic mass of the mandible.     

First-time endoscopic detection of larvae of Gasterophilus spp. in the oral cavity in 14 warmblood horses

Intraoral endoscopy is used as a standard diagnostic technique at the reporting clinics in horses presented with stomatological problems. Endoscopy of the oral cavity was performed using a chip camera, camera control unit, xenon cold light source and a rigid endoscope. In a three year period (2002 to 2004), second instars of Gasterophilus spp. were diagnosed in 14 warmblood horses 2 to 17 years of age. All horses were presented with masticatory problems or problems accepting the bit. In one horse oesophageal obstruction occurred in the course of larval migration. Oral endoscopy can not only be used for the diagnosis of dental disease but also for detection of instars of Gasterophilus spp. in the interdental spaces of maxillary cheek teeth.     

Donkey dental anatomy. Part 1: Gross and computed axial tomography examinations

Post-mortem examination of 19 donkey skulls showed that donkeys have a greater degree of anisognathia (27% width difference between upper and lower jaws) compared to horses (23%). Teeth (n=108) were collected from 14 skulls and examined grossly and by computed axial tomography (CAT). A greater degree of peripheral enamel infolding was found in mandibular cheek teeth (CT) compared to maxillary CT (P<0.001). A significant increase in peripheral cementum from the apical region to the clinical crown was demonstrated in all CT (P<0.0001). All donkey CT had at least five pulp cavities with six pulp cavities present in the 06s and 11s. A new endodontic numbering system for equid CT has been proposed. A greater occlusal depth of secondary dentine (mm) was present in older donkeys (>16 years) than in the younger (<15 years) donkeys studied. Based on gross and CAT examinations, donkey dental anatomy was shown to be largely similar to that described in horses.     

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.     

Treatment of equine cheek teeth by mechanical widening of diastemata in 60 horses (2000-2006)

REASON FOR PERFORMING STUDY: Cheek teeth (CT) diastemata are a significant cause of painful dental disease in horses and limited factual information is available on the treatment of this disorder. OBJECTIVE: To assess the response to mechanical widening in the treatment of diastema. METHOD: Details of the presenting signs and treatment of cases of CT diastema by widening were recorded and the response to treatment of these cases assessed by re-examinations and by obtaining follow-up information from owners. RESULTS: Sixty horses of various breeds, median age 9 years, with clinically significant CT diastemata were classified as having primary (inadequate rostro-caudal CT compression: n = 29) and secondary (to other dental abnormalities: n = 31) diastemata. Quidding was present in 82% of cases, weight loss in 35%, halitosis in 17% and bitting disorders in 12%; 85% of the identified CT diastemata involved mandibular CT and 15% maxillary CT, with caudal CT more commonly affected. Of 273 identified diastemata in the 60 horses, 207 were deemed to have significantly associated periodontal food pocketing and were widened to 4.5-5.5 mm diameter on their occlusal surface using a mechanical burr. The 29 horses with primary diastemata received a median of 1.3 treatments each and at 10 months following their last treatment 72% showed complete remission of signs and 28% showed good improvement. The 31 horses with secondary diastemata received a median of 2.2 treatments each and, at mean 9 months following their last treatment, 48% showed full improvement, 42% good improvement, 6% slight improvement and 3% no improvement. Inappropriate areas of the clinical crown were removed from 4 CT without causing pulpar exposure; one case was reported to have a transient oral infection post treatment and another developed an apical infection in a treated tooth that was unrelated to the diastema widening. CONCLUSION: Diastema widening is an effective treatment of periodontal pocketing in CT diastemata. POTENTIAL RELEVANCE: The described treatment of CT diastema widening by trained personnel is an effective and safe treatment, but repeated treatments are often necessary, especially with secondary diastemata.     

Treatment of maxillary cheek teeth apical infection caused by patent infundibula in six horses (2007–2013)

Six young horses presented with clinical signs of maxillary cheek teeth apical infection (bilateral in 2 horses) that included the presence of rostral maxillary swellings with discharging sinus tracts and were unexpectedly found to have no evidence of endodontic infection in 7 affected teeth. The apical infection of these teeth was attributed to infundibular dysplasia that allowed inoculation of the periapical tissue with contaminated oral contents. Treatment was by debridement and obturation of affected infundibula from their occlusal aspect using techniques normally used for endodontic therapy. Five out of 6 cases showed resolution of clinical signs over a mean follow‐up period of 19 months (range 6–48 months). These cases demonstrate that patency of the infundibular apex is a potential cause of cheek teeth apical infection in young horses, which can be successfully treated by debridement and subsequent infundibular restoration.