Evaluating the Role of Inorganic Elements of Camelus Dromedarius Saliva in Protecting Enamel Against Tooth Surface Loss

The aim of this study was to provide insight into the role of camel's saliva in protecting enamel against erosion and to evaluate the levels of salivary sodium, potassium, calcium, and phosphate ions among 2 groups of camels, those with low-grade tooth surface loss and those with high-grade tooth surface loss. Twenty-eight healthy camels, 5 males and 23 females, aged 20 months to 10 years, were divided into 2 groups. Group I comprise camels with "low-grade tooth surface loss" and Group 2 with "high-grade tooth surface loss." Unstimulated saliva was collected by a draining method. The samples were then analyzed for sodium, potassium, calcium, and phosphate concentrations using automated chemistry analysis. Data were then statistically analyzed using the unpaired Student's t-test and Pearson correlation coefficient test. The study found the salivary calcium and phosphate concentrations were significantly lower in the "high-grade" erosion group, in comparison with the other group (P < .0001 and P  =  .0257, respectively). The results also revealed that the more extensive the tooth surface loss, the more carious lesions the subject had (P  =  .023), and that caries are more common in the anterior teeth, particularly the incisors. The authors conclude that alterations in inorganic elements of saliva, particularly the calcium and phosphate ions, play a major role in the development of resistance to tooth surface loss. This work may represent a direction for future research to develop custom-made preventive supplements, which can protect camelid teeth against tooth surface loss.

Retrospective case review investigating the effect of replacing oaten hay with a non-cereal hay on equine peripheral caries in 42 cases

BACKGROUND

Equine peripheral caries can cause significant morbidity and can have considerable welfare implications. Recent research suggests that diets with high water soluble carbohydrate (WSC) content are associated with high risk of peripheral caries. Previous work has indicated that the condition may be treatable if the inciting cause is removed and the damaged tooth allowed to erupt out, being replaced by the unaffected tooth previously under the gingival margin.

OBJECTIVES

To see whether the peripheral caries process can be ceased if oaten hay (typically high WSC) is removed from the diet and replaced with a non-cereal hay (typically lower WSC).

STUDY DESIGN

Retrospective blinded longitudinal study.

METHODS

Forty-two cases with peripheral caries that were on oaten hay were asked if they would change the hay type from oaten hay to a non-cereal hay or straw (meadow, Rhodes hay, lucerne hay or barley straw). Photographs were taken at the time and then again at subsequent visits. The photographs were anonymised, randomised and scored by six equine veterinary dentists using the Jackson et al. 'Peripheral Caries Grading System' grading scale.

RESULTS

At follow-up, 69.0% of cases were marked as inactive, compared with 47.6% of cases at baseline (OR: 2.45, 95%CI: 1.12-5.36, P = .02). Significantly lower grades of peripheral caries were observed in the gingival, middle and occlusive third of the molars (triadan 9-11's) at follow-up compared with baseline. However, significant improvements were not observed in the premolars (triadan 6-8's).

MAIN LIMITATIONS

This is a review of clinical records, not a prospective study. As such, other changes in the diet and management were not recorded, and there was no control group.

CONCLUSIONS

Recommending clients change their horse's diet from oaten hay (high WSC) to a typically lower WSC hay was associated with significant improvements in equine peripheral caries located in the molars.

A new equine peripheral caries grading system: Are the caries likely active or inactive?

BACKGROUND

Equine peripheral caries can be a significant welfare issue in affected horses. Recent work has shown that complete reversal of the condition may be possible if the primary risk factor can be identified and corrected. Determining whether caries are active (deteriorating) or inactive (improving) is of vital importance when formulating a management and treatment plan. A new grading system is proposed that looks at whether caries are likely active or inactive to assist clinicians deciding whether intervention is required.

OBJECTIVES

To examine the reliability of an alternative grading method for equine peripheral caries.

STUDY DESIGN

Online survey of veterinary surgeons.

METHODS

Reviewers (n = 22) graded images of peripheral caries using three methods: the traditional grading system, a new research grading system and a new clinical grading system. Percentage agreement and Fleiss' kappa were used to examine the participant's agreement of the severity of caries.

RESULTS

All percentage agreements and Fleiss' kappa values were significantly greater than zero (P < .001). The Fleiss' kappa for the new methods were higher (ranging from 0.48 to 0.58), but not significantly different from the traditional method (0.40). There was a high level of consistency in the assessment of caries as either active or inactive with both grading systems reporting over 80% agreement. Feedback on the grading systems was positive with over 90% of reviewers saying they were likely to use the system.

MAIN LIMITATIONS

The use of photographs provided some difficulties with image quality and judging whether the dentin was affected without an occlusal image.

CONCLUSIONS

The new grading system produced a consistent estimate of caries severity and provided high levels of agreement on whether the caries were likely 'active' or 'inactive'. This is likely to be very useful clinically to assist practitioners to determine whether intervention is required.

A Study on the Potential Role of Occlusal Fissure Fractures in the Etiopathogenesis of Equine Cheek Teeth Apical Infections

Thirty-nine equine cheek teeth diagnosed as having anachoretic apical infections and also having occlusal fissure fractures, but without occlusal pulpar exposure, that had been orally extracted without causing occlusal damage and 10 control teeth were used in this study. The teeth were individually imaged by computed tomography, occlusally stained with methylene blue and visually reexamined, then sectioned subocclusally at 5 mm intervals until the fissure fractures could no longer be detected. A limited histological study was then performed on 7 apically infected and 5 control teeth. Standard computed tomography only detected 1 of 39 fissure fractures. Thirteen of the 39 stained teeth had subocclusal fissure fractures visually identified at approximately 6 mm beneath the surface, and in 9 of these 13 teeth the fissure fractures had deeper staining to a level immediately above or into a pulp horn, indicating a potential route for bacterial pulpitis. However, the current study cannot rule out the possibility that the extraction process, long-term formalin storage, or the processing of teeth may have allowed for deeper staining. Additionally, methylene blue may penetrate dental tissue more readily than bacteria can invade. Further studies on the potential role of fissure fractures in the etiopathogenesis of cheek teeth apical infection are warranted.

A histological and ultrastructural study of equine peripheral caries

BACKGROUND

Peripheral caries (PC) has recently been shown to affect over half of UK and Australian horses.

OBJECTIVES

To examine affected cheek teeth histologically and ultrastructurally, to assess the possible route(s) of carious infection into the dental tissues and to further describe the pathological changes in affected teeth.

STUDY DESIGN

Descriptive pathological study.

METHODS

Four control and 16 cheek teeth with different grades of PC were examined grossly, histologically and by electron microscopy.

RESULTS

Cariogenic bacteria from plaque entered peripheral cementum perpendicular to the sides of teeth alongside Sharpey's fibres or vascular channels or more horizontally alongside exposed intrinsic fibres and cemental growth lines. Subsequent intra-cemental bacterial spread created different patterns of caries including vertical and horizontal flake-like patterns; deep, large flask-shaped or smaller superficial ellipsoid-shaped lytic lesions. Cemental caries progressed to affect enamel, dentine and even pulp. Gross examination underestimated the degree of caries observed on histological evaluation.

MAIN LIMITATIONS

No dental histories were available; all teeth were examined on a single occasion.

CONCLUSION

Equine PC causes different patterns of cemental lesions that appear dependent on the route of cariogenic bacterial invasion. Progression of caries can lead to pulpitis and tooth loss. Gross examination can underestimate the true extent of caries.

Prevalence and analysis of equine periodontal disease, diastemata and peripheral caries in a first-opinion horse population in the UK

Equine dental disease remains a widespread affliction in domestic horses, with the potential to cause significant welfare problems. This retrospective study aimed to increase understanding of this aspect of equine health by examining dental records of 932 horses, taken from a 1-year period of first-opinion practice in south-western England and southern Wales. Three grossly-identifiable dental diseases were analysed: equine periodontal disease, diastemata and peripheral caries. The prevalence of active periodontal disease, diastemata and peripheral caries were 13.9%, 8.7% and 8.2%, respectively. Periodontal disease was more common in the mandibular than maxillary arcades (P<0.001) and in the premolar (06-08) than molar (09-11) cheek teeth (P<0.001). Diastemata were also observed more frequently in the mandibular than the maxillary arcades (P<0.001) and in premolar than molar cheek teeth (P<0.001). Peripheral caries were significantly more common in molar than premolar cheek teeth (P<0.001). A positive association was demonstrated between periodontal disease and diastemata (Exp(B)=4.22; P<0.001). Increasing age was a significant risk factor for periodontal disease (P<0.001) and diastemata (P<0.001). Sex was not conclusively established as a risk factor for any dental disease.

Salivary amylase - The enzyme of unspecialized euryphagous animals

INTRODUCTION

Alpha-amylase (EC 3.2.1.1) is the most abundant enzyme in the saliva of man and of several vertebrates. In humans, salivary amylase is mainly formed in the parotid gland; its activity is of high inter-individual and intra-individual variability. The physiological functions of α-amylase have not yet been explored completely. It is well known that the enzyme cleaves the α-(1,4)-glycosidic bonds of polysaccharides. Furthermore it plays an important role in initial bioadhesion in man, facilitating carbohydrate metabolism and bacterial adherence at the tooth surface and therewith caries initiation. Nevertheless, it is still a matter of interest why humans have such high amounts of salivary amylase.

OBJECTIVE

The review presents an evolutionary approach by considering salivary amylase in the animal kingdom with special focus on mammalians divided into the three main nutritional types carnivores, herbivores, and omnivores; it was postulated that for most mammalian animals salivary α-amylase is essential.

RESULTS

The enzyme has been detected in saliva of some herbivores and many omnivorous animals, but not in pure carnivores. Focusing on ruminants, negligible levels or an absence of α-amylase was determined. Presence and activity probably differ depending on the species-specific diet. Animals feeding on unripe fruits, seeds, roots and bulbs exhibit higher activity of salivary α-amylase than species consuming ripe fruits, insects, and vertebrates.

CONCLUSION

In contrast to carnivores and most herbivores, omnivores have considerable amounts of amylase in their saliva. Though, the starch-digesting enzyme has been investigated well, the physiological function of amylase in saliva has not yet been explored completely. It can be hypothesized that nutritional habits affect expression of enzymes in the saliva of animals. It has to be verified, whether α-amylase is genetically or epigenetically determined. As a consequence of the development of agriculture, and following dietary changes, amylase can be recognized as a nutritional and evolutionary marker. Interdisciplinary evolutionary research might offer new perspectives for preventive dentistry.