Dental Braces

Dental braces (also known as orthodontic braces, or simply braces) is a device used in orthodontics to align teeth and their position with regard to a person’s bite. They are often used to correct malocclusions such as underbites, overbites, cross bite and open bites, deep bites, or crooked teeth and various other flaws of teeth and jaws, whether cosmetic or structural. Orthodontic braces are often used in conjunction with other orthodontic appliances to widen the palate or jaws or otherwise shape the teeth and jaws. While they are mainly used on children and teenagers, adults can also use them.

In 500-300 BC, Ancient Greek scholars Hippocrates and Aristotle both ruminated about ways to straighten teeth and fix various dental conditions.

Historians believe that two different men deserve the title of being called “the Father of Orthodontics.” One man was Norman W. Kingsley, a dentist, writer, artist, and sculptor, who wrote his “Treatise on Oral Deformities” in 1880. Kingsley’s writings influenced dental science greatly. Kingsley lived from 1829–1913 and lived in Warren Point, New Jersey. He was a founder of New York State Dental Society in 1868. Also deserving credit is dentist J. N. Farrar, who wrote two volumes entitled “A treatise on the Irregularities of the teeth and their corrections”. Farrar was very good at designing brace appliances, and he was the first to suggest the use of mild force at timed intervals to move teeth.

The American dentist Edward Angle is also widely regarded as a father of modern orthodontics. Practising in the late nineteenth and early twentieth centuries, his eponymous classification of dental arch relationships is used worldwide. His textbook, “Treatment of Malocclusion of the Teeth” was first published in 1907. It went into seven much revised editions and laid the foundation of the modern specialty. After tenure as professor of orthodontics in two medical schools, he went on to found the School of Orthodontia in 1910. He designed several fixed orthodontic appliance systems including the ribbon arch and then the edgewise appliance. These have evolved into the sophisticated pre-adjusted and self-ligating systems used by the great majority of orthodontists today.

Teeth move through the use of force. The force applied by the archwire pushes the tooth in a particular direction and a stress is created within the periodontal ligament. The modification of the periodontal blood supply determines a biological response which leads to bone remodeling, where bone is created on one side of the tooth by osteoblastcells and resorbed on the other side of the tooth by osteoclasts.

Two different kinds of bone resorption are possible. Direct resorption, starting from the lining cells of the alveolar bone, and indirect or retrograde resorption, where osteoclasts start their activity in the neighbour bone marrow. Indirect resorption takes place when the periodontal ligament has become subjected to an excessive amount and duration of compressive stress. In this case the quantity of bone resorbed is larger than the quantity of newly formed bone (negative balance). Bone resorption only occurs in the compressed periodontal ligament. Another important phenomenon associated with tooth movement is bone deposition. Bone deposition occurs in the distracted periodontal ligament. Without bone deposition, the tooth will loosen and voids will occur distal to the direction of tooth movement.

A tooth will usually move about a millimeter per month during orthodontic movement, but there is high individual variability. Orthodontic mechanics can vary in efficiency, which partly explains the wide range of response to orthodontic treatment.

Modern orthodontists can offer many types and varieties of braces:

Traditional braces are stainless steel, sometimes in combination with nickel titanium, and are the most widely used. These include conventional braces, which require ties to hold the archwire in place, and newer self-tying (or self-ligating) brackets. Self-ligating brackets may reduce friction between the wire and the slot of the bracket, which in turn might be of therapeutic benefit.[3]

“Clear” braces serve as a cosmetic alternative to traditional metal braces by blending in more with the natural color of the teeth or having a less conspicuous or hidden appearance. Typically, these brackets are made of ceramic or plastic materials and function in a similar manner to traditional metal brackets. Clear elastic ties and white metal ties are available to be used with these clear braces to help keep the appliances less conspicuous. Clear braces have a higher component of friction and tend to be more brittle than metal braces. This can make removing the appliances at the end of treatment more difficult and time consuming.

Gold-plated stainless steel braces are often employed for patients allergic to nickel (a basic and important component of stainless steel), but may also be chosen because some people simply prefer the look of gold over the traditional silver-colored braces.

Lingual braces are fitted behind the teeth, and are not visible with casual interaction. Lingual braces can be more difficult to adjust, and they can hinder tongue movement.

Progressive, clear removable aligners (examples of which are Invisalign , Originator, ClearCorrect) may be used to gradually move teeth into their final positions. Aligners are generally not used for complex orthodontic cases, such as when extractions, jaw surgery, or palate expansion are necessary.

For less difficult cases spring aligners are also an option that can cost much less than braces or Invisalign (one example is NightShiftOrtho) and still align primarily the front six top and bottom teeth.

A new concept under development is the “smart bracket.” The smart bracket contains a microchip capable of measuring the forces applied to the bracket/tooth interface. The goal of this successfully demonstrated concept is to significantly reduce the duration of orthodontic therapy and to set the applied forces in non-harmful, optimal ranges.

A-braces are another new concept in dental appliances. In the shape of a capital letter A, A-braces are applied, adjusted, removed and completely controlled by the user. At the ends of the A’s arms are angled knobbed bits that the user bites down over. The width between the bits is adjusted by turning the crossbar, housed across the arms. A user never has to experience pain because the pressure is so easy to control. A-braces may serve as self-adjustable retainers and palate expanders.

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