Microscopic Alterations of the Dental Pulp in Surgically Extracted Teeth of Dogs.

Microscopic alterations in the dental pulp of dogs have not been extensively studied. The aim of this study was to investigate microscopic alterations of the dental pulp in dogs' teeth. One hundred and ten surgically extracted teeth (20 incisors, 23 canines, 28 premolars, and 39 molars) from 74 dogs, of different ages, with a history of chronic periodontitis (66 dogs), periapical abscesses (2 dogs), pulpitis (2 dogs), oral cavity neoplasms (2 dogs), dens invaginatus (1 dog), and dental fractures (1 dog) were included. Eight-one maxillary and 29 mandibular teeth were included. Coronal, radicular, and coronal plus radicular calculus were present in 28.2%, 17.3%, and 54.5% of the teeth, respectively. In total 78 teeth (71%) had pulp alterations, including fibrosis (26%), calcification (14%), necrosis associated with the absence of odontoblasts (14%), presence of predentin and dentin inside the cavity (8%), odontoblastic hyperplasia (3%), pigmentation (3%), pulpitis (2%), and pulp stones (1%). Forty-nine (60.5%) of the maxillary teeth and all of the mandibular teeth had pulp alterations. The premolars were most affected, and the molars least affected, by pulp alterations. Pulp fibrosis, calcification, and necrosis were observed in teeth irrespective of the distribution of dental calculus.

Update on Endodontic, Restorative, and Prosthodontic Therapy.

Endodontic therapy is intended to preserve the function of mature teeth with irreversible pulpitis or pulp necrosis or to maintain the vitality of endodontically compromised immature teeth. Standard root canal therapy and vital pulp therapy are 2 mainstays of endodontic treatment. Recent knowledge has improved the outcomes of endodontic treatment with newer materials, such as mineral trioxide aggregate. Composite or prosthodontic crown restoration is also a critical key to success.

Analysis and Assessment of Pulp Vitality of 102 Intrinsically Stained Teeth in Dogs.

Our prospective study analyzed clinical, radiographic, and histological characteristics of 102 intrinsically stained teeth. Sixty-nine dogs ranging from one to fifteen years of age were included in this study. Little more than half of the intrinsically stained teeth had no evidence of coronal injury (53.9%, 55/102). We found that most intrinsically stained teeth were histologically nonvital (87.6%, 85/97) and approximately 2/3 of these (57.7%, 56/97) had no histological endodontic or periodontal inflammation at the time of evaluation. Radiographic evidence of endodontic disease was present in 57% (58/102) of the intrinsically stained teeth. Radiographic evidence of periodontal disease was present in 48% (49/102) of intrinsically stained teeth and 28% (29/102) had radiographic evidence of tooth resorption. 18.6% (19/102) of intrinsically stained teeth were radiographically normal. Evidence of pulp necrosis was common in these intrinsically stained teeth, while only occasional teeth (12.4%, 12/97) had histologically confirmed pulpitis. All teeth with radiographic evidence of periapical lucency had pulp necrosis. Based on our histological findings, the majority of intrinsically stained teeth 87.6% are truly nonvital.

Endodontic Treatment of a Traumatic Tusk Fracture With Exposed Pulp in an Asian Elephant (Elephas maximus).

Tusk fracture in elephants is a common incident often resulting in pulp exposure and pulpitis. Extensive lavage, endodontic therapy, direct pulp capping, or extraction are treatment options. In this report, the successful management of a broken tusk of a juvenile male Asian elephant (Elephas maximus) including morphological analysis of the tusk tip 2 years after surgery are presented. Treatment was carried out under barn conditions and included antimicrobial photodynamic therapy and partial pulpotomy with direct pulp capping. Immediate pain relief was reached. The fractured tusk was preserved and continued to grow. The therapeutic filling material remained intact for over 1 year but was absent 2 years after treatment. The former pulp cavity of the tusk tip was filled with reparative dentin, osteodentin, and bone, but the seal between these hard tissues and pulp chamber dentin was incomplete. Radiographs obtained 3 years after treatment showed no differences in pulp shape, pulp width, and secondary dentin formation between the treated right and the healthy left tusk. It can be concluded that in case of an emergency, the endodontic therapy of a broken elephant tusk can be attempted under improvised conditions with adequate success. Photodynamic therapy might contribute to prevent infection and inflammation of the pulp. The decision tree published by Steenkamp (2019) provides a valuable tool to make quick decisions regarding a suitable therapy of broken tusks.

USE OF COMPOSITE MATERIALS AS A COMPONENT OF TUSK FRACTURE MANAGEMENT IN AN ASIAN ELEPHANT (ELEPHAS MAXIMUS) AND AN AFRICAN ELEPHANT (LOXODONTA AFRICANA).

Tusk fractures in Asian (Elephas maximus) and African elephants (Loxodonta africana) can result in damage to the distal end or to longitudinal cracks, potentially progressing to pulpitis. With pulp exposure, endodontic therapy is the treatment of choice, but conservative therapy has sufficed for some elephants. This manuscript describes the use of composite materials as a component of tusk fracture management. A 7-yr-old male Asian elephant fractured the distal end of both tusks with pulp exposure in one. Capping of each tusk with a Kevlar/fiberglass composite prevented further damage, and a modification allowed care of the exposed pulp tissue. A 34-yr-old male African elephant with a longitudinal crack received a carbon fiber/fiberglass composite circumferential wrap to potentially stabilize the crack. Compression of the crack was achieved, but follow-up was truncated due to bacterial pulpitis. Both cases show that composite material allows for lightweight, durable management of tusk fractures with continued radiographic monitoring.

Gross, computed tomographic and histological findings in mandibular cheek teeth extracted from horses with clinical signs of pulpitis due to apical infection.

REASONS FOR PERFORMING STUDY: The most prevalent type of equine dental pulpitis due to apical infection is not associated with coronal fractures or periodontal disease. The pathogenesis of this type of pulpitis is not fully understood. Computed tomography (CT) is increasingly used to investigate equine dental disorders. However, gross, tomographic and histopathological changes in equine dental pulpitis have not been compared previously. OBJECTIVES: To compare gross, CT and histological appearances of sectioned mandibular cheek teeth extracted from horses with clinical signs of pulpitis without coronal fractures or periodontal disease. To contribute to understanding the pathogenesis of equine dental pulpitis. STUDY DESIGN: Descriptive study using diseased and healthy teeth. METHODS: Mandibular cheek teeth extracted from horses with clinical signs of pulpitis (cases), and from cadavers with no history of dental disease (controls), were compared using CT in the transverse plane at 1 mm intervals. Teeth were then sectioned transversely, photographed and processed for histopathological examination. Tomographs were compared with corresponding gross and histological sections. RESULTS: Cement, dentine and bone had similar ranges of attenuation (550-2000 Hounsfield Units, HU) in tomographs but could be differentiated from pulp (-400 to 500 HU) and enamel (> 2500 HU). Twelve discrete dental lesions were identified grossly, 10 of which were characterised histologically. Reactive and reparative dentinogenesis and extensive pulpar mineralisation, previously undescribed, were identified. Pulpar oedema, neutrophilic inflammation, cement and enamel defects, and reactive cemental deposition were also observed. The CT and pathological findings corresponded well where there was mineralised tissue deposited, defects in mineralised tissue, or food material in the pulpar area. Pulpar and dentinal necrosis and cement destruction, evident grossly and histologically, did not correspond to CT changes. CONCLUSIONS: Computed tomography is useful for identifying deposition and defects of mineralised material but less useful for identifying inflammation and tissue destruction. The equine dentine-pulp complex responds to insult with reactive and reparative changes.

Endodontic therapy of a mandibular canine tooth with irreversible pulpitis secondary to dentigerous cyst.

Dentigerous cysts are uncommon, yet are being reported with increasing frequency in the veterinary literature. Dentigerous cysts are a type of benign odontogenic cyst associated with impacted teeth, most commonly the mandibular first premolar tooth. Significant bone destruction can occur secondary to the expansion of a dentigerous cyst. The expanding cyst can lead to pathology of neighboring teeth, which can include external root resorption or pulpitis. Intraoral dental radiographs are imperative to properly assess the presence and extent of a dentigerous cyst, as well as the status of the neighboring teeth. This case report describes treatment for dentigerous cyst including cyst lining curettage, mandibular bone regeneration, and endodontic therapy for a canine tooth with irreversible pulpitis.

A new understanding of oral and dental pathology of the equine cheek teeth.

Equine dental disease has a high prevalence. Because of developmental, functional, and anatomic differences, limited inference can be made from brachydont dental pathology to that of equine cheek teeth. This article reviews the pathology of equine cheek teeth and their associated oral tissues, with specific information on periodontitis, pulpitis, maxillary infundibular changes, dental fractures, dental overgrowths, mucosal ulceration, and the regenerative capacity of equine teeth.

Magnetic resonance imaging of pulp in normal and diseased equine cheek teeth.

A retrospective analysis of 619 upper and lower cheek teeth from 62 horses was performed. Based on clinical findings, as well as radiographic and magnetic resonance (MR) imaging findings, the teeth were classified into five groups. There were 20 teeth with abnormal MR imaging signals as well as clinical alterations and 599 healthy teeth. Using MR imaging, the appearance of pulp in diseased and disease-free teeth was compared, and the appearance of abnormal pulp was studied. Subsequently, the ability of MR imaging to diagnose pulpitis and pulp necrosis in teeth with normal external appearance was investigated. In horses with clinically verified dental disease, abnormal MR imaging findings were confirmed in the pulp of all affected teeth. An enlarged blurred pulp image with a lower signal intensity was observed only in clinically diseased teeth and was a reliable criterion for diagnosing dental disease on MR imaging. On the other hand, partial or complete absence of pulp in all MR imaging sequences was observed in both diseased and nondiseased teeth. These data demonstrate that pulp changes in equine cheek teeth can be evaluated using MR imaging.

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.

Dens invaginatus of the mandibular first molars in a dog.

A 6-year-old dog was presented for draining tracts associated with both mandibular first molar teeth. Radiographs of the affected teeth showed periapical bone lysis. Surgical tooth extractions were performed and the tooth segments were submitted for histopathologic examination. Microscopic evaluation of the teeth showed in folding of the enamel and dentin consistent with a diagnosis of dens invaginatus. Examination performed 13-months following the extraction procedures indicated uncomplicated healing at the extraction sites and no other visible evidence of endodontic disease.

Induced elephant (Loxodonta africana) tusk removal.

Elephant tusk removal usually requires costly surgical procedures that are time-consuming and present a significant risk to the animal when performed using general anesthesia. Such techniques require gauges, chisels, and forceps to remove the tusk. This article reports the simple removal of the tusk of an 18-yr-old African elephant (Loxodonta africana) without the use of surgical instruments and anesthesia. Rubber elastics were placed around a tusk, causing loss of alveolar bone with subsequent exfoliation of the tusk within 3 wk. The healing process was uneventful.

Results of crown-height reduction and partial coronal pulpectomy in rhesus monkeys (Macaca mulatta).

BACKGROUND AND PURPOSE: In research facilities using non-human primates, crown-height reduction with partial coronal pulpectomy ("vital pulpotomy") is routinely performed on canine teeth of adult male monkeys to reduce self-trauma and the potential for injury to staff or cage-mates. Success of pulpotomy techniques in humans is reportedly 40 to 60%. Failure leads to chronic inflammation and pulp necrosis, which introduces variability in research animals, and may affect research results. The purpose of the study reported here was to determine failure rate of this procedure by evaluating clinical and radiographic findings at 3, 9, and 24 months after crown amputation and partial coronal pulpectomy of maxillary canines in adult male rhesus monkeys. METHODS: Forty-seven maxillary canine teeth from 24 adult male rhesus monkeys were treated by use of crown amputation and partial coronal pulpectomy, using standard dental technique. Follow-up clinical and radiographic examination was performed 3, 9, and 24 months after surgery. RESULTS: At three months after surgery, there was no clinical evidence of failure at any of the teeth. On the basis of radiographic findings, 2 of 47 teeth had failed and one was suspicious for early failure. At nine months, clinical evidence of failure was not apparent; radiographically, 5 of 44 teeth appeared to have failed and 3 others were suspect. Two years post-operatively, failure was clinically evident at two teeth, with radiographic evidence of failure in five teeth, and suspicion of early failure in an additional six of 41 teeth [corrected]. CONCLUSIONS: The failure rate of crown amputation and partial coronal pulpectomy of canine teeth in adult male rhesus monkeys is high, and the chronic inflammation associated with this is cause for concern.

Localized intrinsic staining of teeth due to pulpitis and pulp necrosis in dogs.

Dental charts and records of 71 dogs were received and 84 intact tooth crowns were noted to have been entirely discolored in shades of pink, purple, grey, or tan. Endodontic therapy was performed on 49 of these teeth allowing gross examination of the entire pulp. In exploratory pulpotomy was performed in 15 teeth prior to exodontic therapy in order to assess the integrity of the coronal pulp. Gross signs of partial or total pulp necrosis were present in 59 (92.2%) of these teeth. The pulp was not observed grossly in 20 teeth which received exodontic therapy. Overall, of the 84 teeth evaluated, 36 (42.9%) had no radiographic signs of endodontic disease. Gross or radiographic signs of endodontic disease were absent in only 2 (4.1%) discolored teeth receiving endodontic therapy. Based on the low incidence of vital, affected teeth in the dogs of this study, endodontic on exodontic therapy is recommended for discolored teeth.

Effects of ultrasonic dental scaling on pulp vitality in dogs: an experimental study.

We investigated whether dental pulpal damage is produced as a result of the application of an ultrasonic scaler commonly used in clinical veterinary dentistry. Using methods developed in preliminary studies, we examined six dogs. The radiographic thickness of the dentin and pulp cavity was measured. The ultrasonic scaler was applied to maxillary and mandibular premolar teeth for 30, 60, or 90 seconds, without the use of water as a coolant. The temperatures of the room, the pulp canal on untreated incisor teeth, the cheek, the gingival sulcus, and the dentin of the affected teeth were recorded using a probe with a thermistor attached to a resistivity meter and inserted in the dentin to a depth of 1 mm. Two weeks following scaling, the teeth were extracted for microscopic examination. In another dog serving as a control, the temperature of the dentin was increased to between 45 degrees C (113 degrees F) and 47 degrees C (117 degrees F) and the premolar teeth were removed for microscopic examination 15 days later. We concluded that the application of an uncooled ultrasonic scaler for 90 seconds did not increase the temperature of the dentin. However, damage comparable with acute pulpitis resulted as a consequence of the ultrasonic effect, similar to the effects produced by the 45-47 degrees C heat applied in the control animal.

Lateral condensation in treatment of pulpitis and pulp gangrene: studies on dog canine teeth.

The clinical investigation, carried out in dogs, comprises selected cases of chronic pulpitis and pulpal gangrene of canine teeth resulting from injuries. A group of 20 teeth (group 1) underwent extirpation of pulp, as well as elaboration of a root canal and its filling with Endomethasone paste, under general anaesthesia during a one-stage procedure. The second group of 20 teeth differed from the first in an additional concentration of the paste, due to an introduction of gutta-percha points (lateral condensation). This sealing modification proved to diminish the risk of leaving empty spaces after pulp removal in the pulpitis state. However, in teeth where gangrenous pulp extirpation was performed, lateral condensation was endangered by pushing the paste through beyond the apex. Both anomalies were likely to predispose to the development of apical periodontitis.