Widespread prevalence of Equine Odontoclastic Tooth Resorption and Hypercementosis detected in German Icelandic horse population: impact of anamnestic factors on etiology

OBJECTIVE

To compare anamnestic factors in Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) in affected and nonaffected horses to detect risk factors for horses developing EOTRH.

ANIMALS

A total of 154 Icelandic horses, aged 15 years and older, examined at 22 locations in Lower Saxony, Germany. The investigations took place from October 2020 to December 2021.

METHODS

Anamnestic data were collected using an owner-completed questionnaire. Horses underwent a thorough physical examination and CBC. The rostral oral cavity was clinically examined, and intraoral radiographs of the incisors were taken. Clinical and radiographic findings were scored. Based on the results, the study population was separated into "EOTRH-affected" and "EOTRH-healthy" horses. Both groups were compared to identify differences within the anamnestic factors. In case of inconclusive findings, some horses were classified as "suspicious".

RESULTS

The diagnosis of EOTRH was made in 72.2% (109/151) of horses. The risk of contracting the disease increased with the age of the horse (P = .004). In addition, there was a predisposition for male animals (P = .032). Feeding, keeping, and dental treatments showed no significant influence, while place of birth seemed to influence horses developing EOTRH (P = .017).

CLINICAL RELEVANCE

The results highlight how widespread EOTRH is among the German Icelandic horse population and the need for raising awareness of EOTRH, as many horses were not suspected of having EOTRH beforehand. Moreover, numerous etiological propositions exist, but, to date, no studies have investigated their relevance.

Hypercementosis and odontogenic epithelial hyperplasia associated with a tooth root remnant mimicking a neoplasm. A case report

Hypercementosis presents as painless, single or multiple non-neoplastic cementum formation beyond the physiological limits of the tooth. It often occurs in the apical area of the involved tooth following infection, chemical or mechanical trauma. We report on radiographic and histopathological findings in a single case of late intraosseous hypercementosis and odontogenic epithelial hyperplasia associated with a minute apical tooth root remnant years after its extraction, mimicking a tumour.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) syndrome: suggested pathogenic mechanisms

The syndrome of enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) is an unusual syndrome and is unique to black South Africans. Major criteria for the syndrome are enamel dysplasia with generalized amelogenesis imperfecta-like features and atypical hyperplastic dental follicles with microscopic features of central odontogenic fibroma WHO-type (follicle analogue) attached to the crowns of multiple impacted teeth. Minor features of some cases are anterior open-bite malocclusion, supernumerary teeth, pulpal calcification, aberrant roots with hypercementosis, and hypodontia. The pathogenic mechanisms that lead to the development of EDHFH are unknown. We speculate that faulty synthesis of enamel matrix proteins may interfere with enamel formation and play a role in the generalized enamel hypoplasia described in this syndrome. Alterations in inductive signalling by the odontogenic epithelium mediated by enamel matrix proteins may explain the development of the follicle analogues, the root hypercementosis and the presence of dysplastic cementum deposition juxtaposed to odontogenic epithelium in the gingival overgrowth. Thus, alterations in the function of enamel matrix protein function, may be the common denominator responsible for the development of the EDHFH phenotype.

Osteomyelitis of the mandible associated with autosomal dominant osteopetrosis: a case report

Osteopetrosis is a rare hereditary bone disorder presenting with variable clinical features and is characterized by an increase in bone density. The main clinical findings of the benign-type of osteopetrosis (autosomal dominant) are fractures and osteomyelitis of the mandible, leading to the detection of the disease. We report a case of autosomal dominant osteopetrosis with secondary mandibular osteomyelitis. Clinical and radiological patterns and treatment evaluation were assessed. The patient was referred for evaluation and treatment of an acute abscess in the left side of the face and osteomyelitis of the mandible. Several imaging studies were performed to assess the lesion and the adjacent bone and soft tissue structures. Treatment consisted of intravenous antibiotic therapy, debridement of the necrotic bone and sequestrum, and extra-oral drainage of the abscess, with submandibular access. Healing was uneventful.

Duplication and dilaceration of a crown with hypercementosis of the root following trauma: a case report

Trauma to a primary mandibular central incisor resulted in a rare case of dilaceration and duplication of crown with hypercementosis of the root in the permanent successor. This tooth was extracted. This article highlights the consequences of trauma to a primary tooth for a developing permanent successor.

Repair process of external root resorption subsequent to palatal expansion treatment

The repair process of external root resorption (ERR) and the role of retention mechanics in enhancing ERR repair were studied on eight Macaca fascicularis monkeys that were divided equally into short- and long-term groups. Six monkeys received palatal expansion appliances, and two received sham appliances. The short-term group received active treatment. The long-term group received additional retention (4 months) and relapse (2 months) treatment periods with biweekly injections of individual vital dye per phase, i.e., procion red H-8B and violet H-3R (80 mg/kg B.W.), respectively. Histomorphologic examinations included scanning electron microscopy, light, and ultraviolet microscopy. The short-term group demonstrated penetrated resorption with pulp exposure at sites with initial deficiency of the protecting odontoblastic layer (apical zone, nutrition canal). The long-term group showed two forms of ERR repair: (1) Nonfunctional retarded repair cementum, comprised of overlapped incremental lines and deprived of extrinsic fibers, was delineated in severe pulp exposure. The pulp/dentin complex showed intense incorporation of procion dye in the dentinal tubuli, conceivably related to a defense response in the form of sclerotic dentin. (2) Functional rapid repair cementum, comprised of discriminated incremental lines mainly of mixed cellular cementum, with a consistent pattern of five sequential phases: the lag phase (14 to 28 days), the incipient phase (14 days), the peak phase (14 to 28 days), the steady phase (42 to 56 days) and the retreating phase (70 days). Sharpey's fibers at functional ERR sites were scarce, never emerging from the dentinocemental junction, and not developing into principal fibers. The pulp/dentin complex showed an increase in pulp stones but no formation of tertiary dentin. The apical area responded by hypercementosis in the form of apical occlusion and a displaced pulp canal. The application of a fixed retention device is recommended in light of accelerated apposition of repair cementum during the retention period. However, increased formation of Sharpey's fibers during the relapse period might suggest a restricted duration in splinting therapy.

[Osteitis deformans]

Osteitis deformans is a bone disease of still unknown aetiology which shows characteristic symptoms in the maxillofacial region. An increase in size of the entire calvarium and also of single bones of the facial skeleton belongs to these symptoms. A triad may be seen in the jawbone: osteoporosis, foci of densification and cementum hyperplasia. No possibility of treatment was known in the past. Nowadays, the use of cytostatics, calcitonin and diphosphonates seems to be promising.