Orthodontics comes from the Greek words ortho, meaning correct or straight and odontes meaning teeth. It is a specialized branch of dentistry concerned with the development and management of deviations from the normal position of the teeth, jaws and face (malocclusions). A malocclusion is not a disease but simply a marked variation from what is considered to be the normal position of teeth. Orthodontic treatment can improve both the function and appearance of the mouth and face. Appliances (braces) can be fixed or removable and are used to straighten the teeth and encourage growth and development. The main aims of orthodontic care are to produce a healthy, functional bite, creating greater resistance to disease and improving personal appearance. This contributes to the mental, as well as the physical, well being of the individual.
The 2003 Childrens Dental Health survey found that approximately one third of children would benefit greatly from orthodontic treatment. Indicators of treatment need outcome have been developed and validated by the whole orthodontic profession to assess the efficacy and appropriateness of care. The most widely used are the Index of Orthodontic Treatment Need (IOTN) and the Peer Assessment Rating (PAR).
The IOTN is divided into two parts called the dental health component (DHC) and the aesthetic index (AI).
The DHC is used to quantify the impact of a particular malocclusion upon the long term-term dental health of an individual whereas the AI provides an assessment of the socio-psychological impact through appearance. They are used to categorize malocclusion into five groupings measured from 1 to 5 with the most severe being 5.Â It is generally accepted that IOTN groups 4 & 5 would greatly benefit from orthodontic treatment as well as some individuals from IOTN 3 when the AI is high at 6 or more. The main flaw of this system is that it fails to evaluate the childs perception of need. This may lead to the denial of treatment of children with a genuine socio-dental need.
Holmes found that 38.5% of 12 year olds would greatly benefit from orthodontic treatment. The most common severe problems in a normal population are detailed
|Dental feature||Prevalence in population (%)|
|Cleft lip and palate||0.3%|
|Hypodontia (missing teeth)||1.8%|
|Reverse overjet (lower teeth in front of upper teeth)||2.1%|
|Large overjets (top teeth stick out)||8.8%|
|Crossbite and deviation of jaws on closing||3.0%|
|Deep overbite (lower teeth bite on palate)||4.3%|
|Severe crowding of teeth||9.0%|
|Open bite (teeth do not meet)||0.7%|
Evidence suggests that correcting the following tooth/jaw anomalies with orthodontic appliances will benefit the patients long-term dental health.
Crowding: Teeth may be poorly aligned because the teeth are too large for the mouth. Poor biting relationships and unsightly appearance may all result from crowding of the teeth. The upper canine teeth are on the most frequent culprits.
Deep (traumatic) overbite: Extreme (vertical) overlap of the top and bottom front teeth can lead to them contacting the roof of the mouth causing significant tissue damage and gum stripping. In some patients, this can contribute to excessive tooth and wear and early tooth loss in adulthood.
Increased overjet: Upper front teeth that protrude beyond normal contact with the lower teeth often indicate a poor bite of back teeth and indicate unevenness jaw growth. Thumb and finger sucking habits can also cause prominence of the upper incisor teeth and increase the risk of trauma and permanent damage to the front teeth. A systematic review of the available evidence on this topic found that individuals with and increased overjet had more than double the risk of injury.
Open bite: An open bite results when the upper and lower front teeth do not touch when biting together. This leads to all the chewing pressures being places on the back teeth, which may cause these teeth to wear down quicker. It may also make the patients biting less efficient, which may cause social problems especially at meal times.
Spacing: If teeth have not developed or are missing, or smaller than average in size, unsightly spaces may occur between the teeth. This is a less common problem though when compared with compared with patients who have significant crowding of their teeth. Some malocclusions have a greater adverse effect on quality of life than other types. Individuals with four or more missing teeth have been shown to have poorer quality of life scores.
Crossbite: This occurs when the upper front teeth bite inside the lower teeth i.e. towards the tongue. This can lead to one or more of the lower incisors teeth becoming mobile with early receding of the gums. It can also occur on the back teeth and is best corrected at an early age e.g. 8-10 years, due to biting and chewing difficulties as a result of the deviated bite and associated displacement of the lower jaw.
Reverse overjet or lower jar protrusion: approximately 3-5% of the population have a lower jaw that is significantly longer than their upper jaw. This causes them to bite their lower front teeth ahead of the upper front teeth thus creating a total crossbite of the teeth. It can also lead to significant wearing down of the tips of the upper front teeth.
One of the most significant effects of a malocclusion is its psycho-social impact on the individual patient. There is little doubt that a poor dental appearance can have a profound psycho-social effect on children. Shaw et al. (1980) found that children were teased more about the teeth than anything else e.g. clothes, weight, ears. A persons dental appearance can have a significant effect on how they feel about themselves. Children and adolescents with poor teeth can often become targets for teasing and harassment from other children. This results in these patients being unsure of themselves in social interaction and having lower self-esteem.
Adolescents who complete orthodontic treatment report fewer oral health impacts on their daily life activities than those who had never had treatment. Groups of children who need orthodontic treatment exhibit significantly higher impacts on their emotional and social well-being. Malocclusion has a negative impact on the oral health related quality of life of adolescents. Children aged between 11 and 14 years old with malocclusion demonstrate significantly more impacts i.e. worse quality of life, compared with a minimal malocclusion group based on the IOTN.
Johal et al. (2006) investigated the impact that a malocclusion has on a childs quality of life by assessing the effect of an increased overjet (>6mm) or spaced front teeth. These groups of children also had more significant social and emotional issues than children with well-aligned teeth. Their research also found that both these occlusal traits had a significant negative impact on the quality of life of their parents and other family members.
Shaw et al. (2007) carried out a major multi-disciplinary longitudinal study in Cardiff back in 1981 of an initial sample of 1,018 11-12 year olds. A 20-year follow-up study looked at the dental and psycho-social status of individuals who received, or did not receive, orthodontics as teenagers. Unfortunately, only a third (n=337) of the original sample could be re-examined in 2001 due to a 67% dropout rate. Those patients with a prior need for orthodontic treatment, who had treatment completed as a child, demonstrated better tooth alignment, better self-esteem and satisfaction with life scores. However, orthodontics seemed to have little positive effect on psychological health and quality of life in adulthood. Unfortunately, this long-term study suffered with problems of an archaic treatment regime (mainly removable appliances being used), antique methodology and short retention regime. Its relevance to 21st century orthodontics is therefore debatable.
In summary, it appears that both psycho-social and functional handicaps can produce a significant need for orthodontic treatment in addition to the dental health benefits described.
The benefits of orthodontic treatment include an improvement in dental health, function, appearance and self-esteem. These perceived benefits are described in more detail below. Prospective patients (and their parents) seem to be confident of the gains that they expect to achieve by undergoing a course of orthodontic treatment. The benefits of orthodontic treatment often go beyond improving a persons dental health. People may feel they look better, which can contribute to self-esteem and ones overall quality of life.
In the vast majority of well-planned cases, the benefits or orthodontic treatment outweigh the possible disadvantages. Patient education and the selection of appropriate treatment plans for individuals reduce this risk considerably. The most important aspect of orthodontic care is to have an extremely high standard of oral hygiene before and during orthodontic treatment.
Demand for orthodontic treatment?
Orthodontics has played an increasing role in dentistry over recent years and this trend is likely to continue in the future. Recent surveys of the long-term effects of orthodontic treatment reveal that a vast majority of individuals who have undergone orthodontic treatment feel they have benefited from the treatment and are pleased with the results. Many patients will demonstrate dramatic changes in their dental and facial appearance.
It is well known that not all patients with malocclusion, even those with extreme deviations from normal, seek orthogonal treatment. The perceived need for treatments influenced by both social and cultural factors and currently the demand for treatment greatly exceeds the resources available. There has been a marked increase in demand from both adults and children seeking treatment since the 1980s as a result of more dental awareness by the public in conjunction with an increased acceptance of fixed braces.
Each year, in excess of 130,000 patients (most of whom are children under the age of 18 years) have braces fitted under the NHS in England and Wales. There is a wide range of opinion on the best time to start orthodontic treatment but the vast majority is carried out on children who have lost all their baby (deciduous) teeth and have most of their adult (except for wisdom teeth) present in the mouth. This means that the earliest the majority of children commence their orthodontic treatment is between 11-12 years of age.
Orthodontic treatment provided whilst many of the baby teeth are still present in the mouth, i.e. at age 7-9 years, is regarded as early or interceptive treatment. A common example of this type of orthodontic treatment is in cases with anterior and/or lateral crossbites with jaw displacement on mouth closure. Simple expansion appliances (removable or fixed types) are usually employed to deal with this clinical situation over a few months. Another example of valid interceptive orthodontic treatment is where the timely removal of a baby tooth can enable the spontaneous (natural) correction of a dental centreline shift or allows an off-track (ectopic) adult tooth to erupt into its correct position in the mouth without the need for braces.
Most UK orthodontics do not favour early treatment to correct increased overjets, deep overbites or severe dental crowding and prefer to carry out this treatment at the more ideal age of 10-12 years or later. Early treatment for increased overjets is commonplace in the USA and Europe. It is described as two phase treatment as it involves a period of early active treatment with a functional or removable appliance followed by a second phase with braces once all the adult teeth are present in the mouth. This compares with one phase treatment of adult teeth where the functional and fixed brace treatment are combined thereby reducing the overall treatment time and possibly cost. The optimal timing for treatment of children with increased overjets remains controversial ad needs to be based on individual indications for each child. Good communication skills can identify specific children whose psychological well being can be improved by early treatment.