Fixed appliances are a type of braces used to treat malocclusion. Currently this is the most popular type of braces. They can cause multiple tooth movements simultaneously and more effectively. They are also favoured (well liked) by the patients.
Fixed appliances are orthodontic devices/ braces which are fixed onto the tooth surfaces. They cannot be removed by the patient.
Types of Fixed Appliance
There are several types, brands and designs of fixed appliances. They may be classified according to;
- The tooth surface on which brackets are placed
- Labial appliances (the front surface of the tooth facing the lips or cheeks)
- Lingual appliances (the back surfaces of tooth facing the palate or tongue)
- Materials from which brackets are fabricated
- Stainless steel
- According to the method of ligation of archwires to the brackets
- Conventional (tied with elastomeric modules or stainless steel ligatures)
- Self Ligating (using clips)
Components Of Fixed Appliance
- Components which are bonded to the teeth.
- Rings made of stainless steel which are cemented to the molar teeth to which buccal tubes are welded for archwire placement. (nowadays these there are also bondable buccal tubes attached directly to the tooth surfaces).
- Wires that link all the brackets and bands/ tubes together.
- Elastomeric Module/Ligature
- Elastomers or stainless steel ligatures which are used to tie the archwire to brackets.
Indications for Fixed Appliances
- Many teeth need to be moved simultaneously
- Multiple types of complex tooth movements are required (tipping, torqueing, intrusion, extrusion)
- When teeth in both the upper and lower arches require treatment
- When bodily tooth movements of the teeth are necessary
Criteria for Wearing Fixed Appliances
- Indications as previously stated above
- Oral hygiene must be excellent
- Patient must be motivated and able to follow the orthodontist’s instructions. (compliant)
Good dietary habit is an important consideration in wearing fixed appliances to prevent breakages. If there are breakages (e.g dislodged brackets, loosened bands or fractured archwire), the duration of treatment may be prolonged and the treatment results may be as compromised.
The following advice must be followed:
- Avoid hard food such as nuts, ice, candy etc
- Avoid chewy and sticky foods such as chewing gums etc
- Any whole hard fruits should be cut into small pieces
- Chicken or meat should be cut into small pieces
Duration Of Treatment with Fixed Appliance
On average, treatment with fixed appliances will take about 2 years to complete. However, the duration is also dependent on the complexity of the cases and whether the cases are treated with or without extraction of teeth. Some cases may have shorter treatment time and some may need a longer treatment duration.
Factors That Affect Treatment Success
There are several factors which can influence treatment outcome. Some of the factors may be within the control of the patients. However some factors are beyond patient control.
Factors That Can Be Controlled
- Oral Hygiene
- Poor oral hygiene can cause tooth decay (caries) and gum disease (gingivitis)
- Patients are advised to brush teeth with fluoridated toothpaste after every meal and to use a special brush (interdental brush) to clean in between the brackets.
- Patients are also advised on flossing and rinsing with fluoride mouthwash to maintain good oral health.
- Patient’s cooperation/ compliance
- It is important to maintain proper oral hygiene and follow dietary advice.
- Some patients may be instructed to wear elastics and other auxiliaries to help facilitate tooth movements. They must adhere to the instructions given.
- It is important to follow dietary advice to prevent damage of the brackets or archwires.
- Patients are usually given appointments every 6 to 8 weeks
- However If patient encounter pain due to poking of archwires or loosening of brackets, they have to call the clinic for an earlier appointment to address the problems.
- During the course of treatment, failure to keep appointments given may prolong treatment time.
- Frequent breakages may also increase duration of treatment.
Factors Beyond Patient’s Control
- Damage to The Nerve Supply
- Sometimes tooth movements may result in the tooth becoming non vital (dead). This may occur to a tooth that has been traumatized from a deep restoration or previous injury or by excessive force application. When this happens, root canal therapy may be required to save the tooth. However, these situations only occur rarely.
- Root Resorption
- Tooth movements usually cause root ends of the teeth to become shortened about 1-2mm. This is called root resorption. However, it usually is mild and does not affect the health of the tooth.
- Some teeth have a slight tendency to rebound to their original position. This is called relapse. Wearing retainers after treatment help minimize relapse.
- Late Growth Changes
- Adverse growth of the maxilla and / or the mandible may cause changes in tooth position and changes in occlusion / bite.
- Late jaw growth after treatment can also cause tooth movements and relapse.
- Satisfactory Outcome (Pictures 3 and 4)
- A successful and satisfactory treatment outcome would be reflected by teeth that are well aligned and with improved occlusion. The oral health should also remain optimum.
- Unsatisfactory treatment Outcome
|Last Reviewed||:||28 August 2020|
|Translator||:||Dr. Noorunisa bt. Shawal Ahmad|
|Accreditor||:||Dr. Norlian bt. Hj. Daud|
|Reviewer||:||Dr. Hjh. Rashidah bt. Dato’ Hj. Burhanudin|