Tooth wear is the loss of dental hard tissue that was not caused by decay and represents a common clinical problem of modern man. In the etiology of dental hard tissue lesions there are three dominant mechanisms that may act synergistically or separately:friction (friction), which is caused by abrasion of exogenous, or attrition of endogenous origin, chemical dissolution of dental hard tissues caused by erosion, occlusal stress created by compression and flexion and tension that leads to tooth abfraction and microfracture. Wear of tooth surfaces due to the presence of microscopic imperfections of tooth surfaces is clinically manifested as sanding veneers. Tribology, as an interdisciplinary study of the mechanisms of friction, wear and lubrication at the ultrastructural level, has defined a universal model according to which the etiopathogenesis of tooth wear is caused by the following factors: health and diseases of the digestive tract, oral hygiene, eating habits, poor oral habits, bruxism, temporomandibular disorders and iatrogenic factors. Attrition and dental erosion are much more common in children with special needs (Down syndrome). Erosion of teeth usually results from diseases of the digestive tract that lead to gastroesophageal reflux (GER) of gastric juice (HCl). There are two basic approaches to the assessment of the degree of wear and dental erosion. Depending on the type of wear (erosion, attrition, abfraction), the amount of calcium that was realised during the erosive attack could be determined qualitatively and quantitatively, or changes in optical properties and hardness of enamel could be recorded, too. Abrasion of teeth (abrasio dentium) is the loss of dental hard tissue caused by friction between the teeth and exogenous foreign substance. It is most commonly provoked by prosthetic dentures and bad habits, while its effect depends on the size of abrasive particles and their amount, abrasive particle hardness and hardness of tooth surfaces. Attrition of teeth (attritio dentium) represents teeth wear during mastication, friction on the tooth or teeth during parafunctional mandibular movements (bruxism), but without the abrasive effect. Dental erosion (erosio dentium) or corrosive wear is a progressive, irreversible loss of dental hard tissue resulting from the effect of acids and /or chelation in the mouth, but without the participation of bacteria. Acids, of either exogenous or endogenous origin (peptic ulcer, gastritis, or bulimia, anoreksia nervosa), that come into the mouth can lead to different clinical manifestations of erosion depending on the time of exposure, the microstructure of teeth, buffering capacity, the amount of saliva and other factors. The changes are visible on the palatal surfaces of upper anterior teeth and, in severe cases, the lingual surfaces of posterior teeth. Occupational dental erosion occurs during exposure to industrial gases that contain hydrochloric or sulfuric acids, as well as the acids used in galvanizing and manufacture of battery and weapons. Due to the multifactorial nature of erosive tooth wear preventive measures must be applied taking into account chemical and biological factors as well as the patient's behavior associated with the etiology and pathogenesis of erosion. It is recommended to consume food and drinks that stimulate the secretion of large amounts of saliva base; to use neutral or alkaline mouthwash, and to chew sugar-free gum; to apply adequate oral hygiene (soft brushes, non-abrasive tooth paste, proper washing technique) and not to consume aciding food and carbonated soft drinks and fizzy drinks in a great amount and frequently. It is necessary to apply preparations with high content of fluoride, and lubricant of tooth wear (powder CaF, CaF mixture and olive oil), and asset-based titanium tetrafluoride and casein-calcium phosphate. Commercial tooth paste that contains CPP-ACP (casein phosphopeptide-amorphous calcium phosphate) and calcium phosphate nanocomplexes is now available. Its use is equally effective in acidic and in neutral media. In the prevention of tooth wear, lasers (CO2, Nd:YAG) and enzymes (matrix metalloproteinases) are being used more frequently in modern dental practice. Depending on the degree of tooth wear, the restorative procedure, may consist of bonded composites, or glass ionomer cement restorations of tooth wear, as well as complete reconstruction of the crown (prosthetic rehabilitation) in cases of severely destroyed dentition.
