The human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla or the mandible and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.
Dental materials are specially fabricated materials, designed for use in dentistry. There are many different types of dental material, and their characteristics vary according to their intended purpose. Examples include temporary dressings, dental restorations, endodontic materials, impression materials, prosthetic materials (dentures), dental implants,
Dentin or dentine is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by enamel on the crown and cementum on the root and surrounds the entire pulp. By volume, 45% of dentin consists of the mineral hydroxylapatite, 33% is organic material, and 22% is water. Yellow in appearance, it greatly affects the color of a tooth due to the translucency of enamel. Dentin, which is less mineralized and less brittle than enamel, is necessary for the support of enamel. Dentin rates approximately 3 on the Mohs scale of mineral hardness. There are two main characteristics which distinguish dentin from enamel: firstly, dentin forms throughout life; secondly, dentin is sensitive.
A dental restoration or dental filling is a treatment to restore the function, integrity, and morphology of missing tooth structure resulting from caries or external trauma as well as to the replacement of such structure supported by dental implants. They are of two broad types—direct and indirect—and are further classified by location and size. A root canal filling, for example, is a restorative technique used to fill the space where the dental pulp normally resides.
Toothache, also known as dental pain, is pain in the teeth or their supporting structures, caused by dental diseases or pain referred to the teeth by non-dental diseases. When severe it may impact sleep, eating, and other daily activities.
The process of tooth whitening lightens the colour of a tooth. Tooth whitening can be achieved by either changing the intrinsic colour or by removing and controlling the formation of extrinsic stains. The chemical degradation of the chromogens within or on the tooth is termed as bleaching. Hydrogen peroxide is the active ingredient most commonly used in whitening products and is delivered as either hydrogen peroxide or carbamide peroxide. Hydrogen peroxide is analogous to carbamide peroxide as it is released when the stable complex is in contact with water. When it diffuses into the tooth, hydrogen peroxide acts as an oxidising agent that breaks down to produce unstable free radicals. In the spaces between the inorganic salts in tooth enamel, these unstable free radicals attach to organic pigment molecules resulting in small, less heavily pigmented components. Reflecting less light, these smaller molecules create a "whitening effect". There are different products available on the market to remove stains. For whitening treatment to be successful, dental professionals should correctly diagnose the type, intensity and location of the tooth discolouration. Time exposure and the concentration of the bleaching compound, determines the tooth whitening endpoint.
Abrasion is the non carious, mechanical wears of tooth from interaction with objects other than tooth-tooth contact. It most commonly affects the premolars and canines. Based on clinical surveys, studies have shown that abrasion is the commonest aetiological factor for development of non-carious cervical lesions (NCCL) and is most frequently caused by incorrect toothbrushing technique.
Dentinogenesis imperfecta (DI) is a genetic disorder of tooth development. This condition is a type of dentin dysplasia that causes teeth to be discolored and translucent giving teeth an opalescent sheen. Although genetic factors are the main contributor for the disease, any environmental or systemic upset that impedes calcification or metabolisation of calcium can also result in anomalous dentine.
Dentin hypersensitivity is dental pain which is sharp in character and of short duration, arising from exposed dentin surfaces in response to stimuli, typically thermal, evaporative, tactile, osmotic, chemical or electrical; and which cannot be ascribed to any other dental disease.
Dens invaginatus (DI), also known as tooth within a tooth is a rare dental malformation found in teeth where there is an infolding of enamel into dentine. The prevalence of condition is 0.3 - 10%, affecting more males than females. The condition is presented in two forms, coronal and radicular, with the coronal form being more common.
Dens evaginatus is a rare odontogenic developmental anomaly that is found in teeth where the outer surface appears to form an extra bump or cusp.
A luting agent is an application of a dental cement. Luting agents connect an underlying tooth structure to a fixed prosthesis, hence giving rise to the term, luting agent, as they lute, or glue, two different structures together. There are two major purposes of luting agents in Dentistry – to secure a cast restoration in fixed prosthodontics, and to keep orthodontic bands and appliances in situ.
Dental cements are a group of materials with a wide range of dental and orthodontic applications. Common uses include temporary restoration of teeth, cavity linings to provide pulpal protection, sedation or insulation and cementing fixed prosthodontic appliances.
Dental trauma refers to trauma (injury) to the teeth and/or periodontium, and nearby soft tissues such as the lips, tongue, etc. The study of dental trauma is called dental traumatology.
The Hall Technique is a non-invasive treatment for decayed baby back (molar) teeth. Decay is sealed under preformed crowns, avoiding injections and drilling. It is one of a number of biologically orientated strategies for managing dental decay.
Pulp capping is a technique used in dental restorations to prevent the dental pulp from necrosis, after being exposed, or nearly exposed during a cavity preparation. When dental caries is removed from a tooth, all or most of the infected and softened enamel and dentin are removed. This can lead to the pulp of the tooth either being exposed or nearly exposed which causes pulpitis (inflammation). Pulpitis, in turn, can become irreversible, leading to pain and pulp necrosis, and necessitating either root canal treatment or extraction. The ultimate goal of pulp capping or stepwise caries removal is to protect a healthy dental pulp and avoid the need for root canal therapy.
Root fracture of the tooth is a dentine cementum fracture involving the pulp.
An enamel fracture, or chip, is a complete fracture of the tooth enamel without the involvement of the dentine and pulp. A fracture occurs when a tooth contacts a hard object with enough force to break a section of enamel. Chips form with minimal plastic deformation since enamel is strong but brittle. A fracture typically occurs as an irregular break on the occlusal edge of the enamel, and is therefore different to other forms of tooth wear that leave smooth surfaces. Pulp sensibility testing is recommended to confirm pulpal health. Treatment depends on the size of the fractures. If a tooth fragment is still available, it can be bonded to the tooth. For small or minor fractures, it can be smoothed to remove rough margins and edges. For a larger or major fractures, dental composite resin can be used to mask the defective enamel for aesthetic purpose. In archaeological samples enamel fractures can give insight into the diet and behaviour of past populations.
