Roberts Harry1 and J Sandy2

The intra-oral assessment examines the oral health, individual tooth positions and inter-occlusal relationships. When this has been completed in conjunction with the extra-oral examination, a treatment plan can then be formulated. 1 Consultant Orthodontist, Orthodontic Department, Leeds Dental Institute, Clarendon Way, Leeds LS2 9LU 2Professor in Orthodontics, Division of Child Dental Health, University of Bristol Dental School, Lower Maudlin Street, Bristol BS1 2LY Correspondence to D....

Dental Health

Surprisingly there is no strong association between dental irregularity and dental caries or periodontal disease. It seems that dietary factors are much more important than the alignment of the teeth in the aetiology of caries. Although straight teeth may be easier to clean than crooked ones, patient motivation and dental hygiene seems to be the overriding factor in preventing gingivitis and periodontitis. That said, few of the studies that have investigated the link between crowding and...

Poor appliance design

Failure to adequately retain the appliance, or incorporate as many teeth into the anchor block as possible are common causes of anchorage loss. If fixed appliances are used, as many Fig. 8a A neck strap. Note the snap away safety mechanism Fig. 8b An occipital high pull headgear again with a snap away safety system Fig. 8c A variable pull Interlandii headgear. A rigid plastic strip is employed as a safety mechanism to prevent the facebow disengaging from the molar bands and coming out of the...

Interceptive Measures For Canines

Picture Orthodontic Gold Chain

One of the most significant publications in the orthodontic literature came from Ericson amp Kurol 1988 1 who demonstrated that extraction of upper deciduous canines where the upper permanent canines were developing on the palatal aspect, resulted in nearly an 80 chance of correcting the impaction. The paper was very specific about what types of malocclusions this could be applied to. Nearly all the cases were Class I with no incisor crowding. This is important to emphasise, a subsequent...

Overbite reduction

Deep Overbite Treatment

Removable appliances are very effective in correcting a deep overbite, especially in a growing patient. An upper removable appliance with an anterior bite plane is used which disengages the molars by 2-3 mm whilst at the same time establishing lower incisor contact with the bite plane Fig. 6 . Eruption of the posterior teeth produces a reduction in the overbite. It is essential that the inter-incisor angle is corrected at the completion of treatment so that an occlusal stop between the upper...

B A Degree of crowding

The lower incisor edges occlude with or lie immediately below the cingulum plateau middle part of the upper central incisors. Class II. The lower incisor edges lie posterior to the cingulum plateau of the upper central incisors. There are two divisions Division 1 there is an increase in the overjet and the upper central incisors are usually proclined. Division 2 the upper central incisors are retroclined. The overjet is usually minimal but may be increased. Class III. The lower incisor...

Orthodontics And Temporomandibular Dysfunction

Relatively recently, orthodontists have been concerned about the possibility of a link between the orthodontic treatment they provide and tem-poromandibular dysfunction TMD which is a Temporomandibular joint problems are not caused or cured by orthodontic treatment Litigation forced orthodontists into generating objective scientific research into the effects of orthodontic treatment common finding in the population. Longitudinal studies show that the prevalence of signs and symptoms of TMD...

What Are The Best Radiographic Views To Locate Canines

Exposure Palatal Canine

Most patients undergoing routine orthodontic screening will have a dental pantomogram. Location of tooth position requires two radiographs in different positions. In the interests of radiation hygiene it is sensible to use this as a base x-ray and to take further location radiographs in relation to the dental pantomogram. An anterior occlusal radiograph allows this and the principle of vertical parallax can be used to locate the position of the canine. The tube has to shift in order to take an...

First molars

Ulcers After Extraction Second Molar

First permanent molars are often the first permanent teeth to erupt into the mouth. Their deep fissure morphology predisposes them to caries and poor tooth brushing combined with a high sugar intake, may result in gross caries. Heavily restored or decayed first molars should be considered for removal over other non-carious teeth Fig. 12 . First molars extraction requires careful planning. Their position in the arch means that whilst relief of premolar crowding is achieved the space created is...

Vertical dimension

Vertical Dimension Occlusion

This dimension gives some indication of the degree of overbite. The vertical dimension is usually measured in terms of facial height and the shorter the anterior facial height the more likely it is that the patient will have a deep over-bite. Conversely the longer the facial height the more the patient is likely to have an anterior open bite. Deep overbites associated with a short anterior facial height and open bites with long face heights are difficult to correct with orthodontics alone. The...

Tipping

Adam Central Incisor

One of the major uses of removable appliances is to move one incisor over the bite as shown in Figs 2a-d. A simple upper removable appliance utilized a 'T' spring constructed from 0.5 mm wire activated 1-2 mm which delivered a force of about 30 g to the tooth. After only a few weeks the cross bite was corrected without the need for complex treatment. Note the anterior Fig. 1a-c A 9 year-old patient with an anterior open bite caused by a thumb sucking habit. Note the wear on the thumb as a...

Enamel wear

Picture Enamel Fracture Orthodontics

Wear of enamel against both metal and ceramic brackets abrasion may occur. It is common on upper canine tips during retraction as the cusp tip hits the lower canine brackets Fig. 5 . It may also be seen on the incisal edges of upper anterior teeth where ceramic brackets are placed on lower incisors.17 Ceramic brackets are very abrasive and therefore contraindicated for the lower anterior teeth where there is any possibility of the brackets occluding with the upper teeth, bearing in mind that...

Retrieval And Preservation Of Anchorage

Palatal Anchorage Reinforcement

Extra-oral devices can be used for distal movement as well as anchorage reinforcement. For anchorage control wearing the headgear at night-time only is usually enough. In order to produce distal movement, the patient should wear the appliance in excess of 12 hours usually for the evenings as well as at nighttime. While some practitioners increase the force levels for distal movement purposes, it is our experience that this is not necessary and a force of approximately 250-300 g per side is...

Supplemental teeth

Tuberculate Type Supernumerary Tooth

There are some conditions which have a genetic basis where impacted teeth are seen more frequently and this includes cleidocranial dysplasia, cleft lip and palate, gingival fibromatosis and Down's Syndrome. It is worth remembering that most central incisors should have erupted by the age of 7 and lateral incisors by the age of 8. Surprisingly, most referrals for impacted maxillary incisors are when the patient is 9 years of age. This delay in diagnosis could potentially influence the outcome...

Anteriorposterior AP

Although precise skeletal relationships can be determined using a lateral cephalostat radiograph, many practices do not have this facility and it is important to be able to assess the skeletal relationships clinically. To assess the AP skeletal pattern the patient has to be postured carefully with the head in a neutral horizontal position Frankfort Plane horizontal to the floor . Different head postures can mask the true relationship. If the head is tipped back the chin tends to come further...

Correction of canine position Favourable indications for correction of impacted canines

Piggyback Orthodontic Wire

Canines are moved most easily into their correct position if the root apex is in a favourable position. If the tooth lies horizontally it is extremely difficult to correct this and generally the closer the tooth to the midline the more difficult the correction will be. Treatment is nearly always lengthy and can damage adjacent teeth. Figure 13 shows a lateral incisor adjacent to a palatally impacted canine where the opposite reaction to Fig. 13 A lateral incisor adjacent to a palatally impacted...

Tempromandibular dysfunction TMD

Kloehn Type Head Gear

Much attention in the literature has been focused on the relationship between TMD and orthodontic treatment. Whilst TMD is common in the orthodontic aged population whether orthodontic treatment is carried out or not, there is no evidence to support the theory that orthodontic treatment causes TMD or cures it.29 Pre-existence of TMD should be recorded, and the patient advised that treatment will not predictably improve their condition. Some patients may suffer with increased symptoms during...

Functional Appliances

These are powerful appliances capable of impressive changes in the position of the teeth. They are generally used for Class II Division I malocclusions although they can be used for the Fig. 12c Upper first and lower second premolars were extracted and the canines surgically exposed Fig. 12d A tri-helix was used to expand the upper arch and a sectional fixed appliance used to pull the canine into the line of the arch Fig. 12a, b Pre treatment photographs of a patient with palatally impacted...

Bone Bending Piezoelectric And Magnetic Forces

Undermining Resorption

There was considerable interest in piezoelectricity as a stimulus for bone remodelling during the 1960s. This arose because it was noted that distortion of crystalline structures generated small electrical charges, which potentially may have been responsible for signalling bone changes associated with mechanical forces. The interest therefore in 'electricity' and bone was considerable. Magnets have been used to provide the force needed for orthodontic tooth movement. Classically an unerupted...