Textbook Flashcards
orthodontics
branch of dentistry concerned with facial growth, development of the dentition and occlusion and the diagnosis, interception and treatment of occlusal anomalies
ideal occlusion
term given to dentition where the teeth are in the optimum anatomical position, both within the mandibular and maxillary arches (intramaxillary) and between the arches when the teeth are in occlusion (intermaxillary)
malocclusion
term used to describe dental anomalies and occlusal traits that represent a deviation from the ideal occlusion
In reality, rare to have a truly perfect occlusion and malocclusion is a spectrum – variation around the norm
prevalence of occlusal abnormalities
depends on population studied (e.g age and racial characteristics), criteria used for assessment, methods used by examiners (e.g. if radiographs used)
rationale for orthodontic treatment
Malocclusion may cause concerns related to the dental health and/or oral health related quality of life issues arising from appearance, function and psychosocial impact of teeth
Need for treatment depends on the impact of the malocclusion and whether treatment is likely to provide a demonstrable benefit to the pt
Need for ortho Tx depends on
the impact of the malocclusion and whether treatment is likely to provide a demonstrable benefit to the pt
to judge treatment need
potential benefits of Tx balanced against the risk of possible complications and side effects in a risk-benefit analysis
benefit of ortho Tx (4)
Improved dental health
Improved oral health related quality of life
Improved aesthetics
Improved function
risks of ortho Tx (3)
Worsening of dental health
Failure to achieve aims of Tx
Relapse
why do people need ortho Tx
Health and wellbeing benefits are the most appropriate determinant of Tx need
Orthodontic indices have been developed to help objective and systematic evaluation of the potential risk to dental health posed by malocclusion and the possible benefits of orthodontic treatment
reason for orthodontic indices
been developed to help objective and systematic evaluation of the potential risk to dental health posed by malocclusion and the possible benefits of orthodontic treatment
While indices were mainly developed to measure treatment need, due to high treatment demand in many countries they are also used to manage demand and support prioritisation through some form of rationing
e.g. Uk acceptance for NHS orthodontics is based on need for treatment determined by the Index of Orthodontic Treatment need (IOTN), Sweden treatment priority is estimated using priority index developed by Swedish Orthodontic Board and the Medical Board – most severe first
unmet ortho Tx depends on (3)
Individuals desire for treatment
Organisation factors – availability and access to services,
Cost
UK unmet ortho treatment need for children from deprived houses is 40% 12 yo and 32% 15 yo (higher than average)
Similar inequality patterns for access to Tx seen in other countries
demand and willingness for ortho care
higher in females, and higher SES, smaller population: orthodontist ratio (assumed to be because increase awareness and acceptance of appliances)
Demand for treatment does not reflect the objective treatment need
Some pts very aware of minor deviations- e.g. mild rotation upper incisors – whilst others refuse Tx for severe malocclusions
Demand increasing as rise in less visible appliances (ceramic brackets, lingual fixed appliances, orthodontic aligners). As well as increasing dental awareness and desire for straight teeth – more acceptance also means many adults who didn’t have tx when young now want
ortho role with restorative
adjunctive
- People keeping teeth for longer is contributing for more requests for interdisciplinary care
ortho relation to caries, plaque induced perio and TMD
insufficient evidence that ortho treatment beneficial
- Complex and multifactorial in origin, thus direct casual relationship with malocclusion ins difficult to measure effectively
ortho relation to localised periodontal problems
certain occlusal anomalies can predispose, particularly where the gingival biotype is thin, here orthodontic intervention can have a long term health benefit
e. g.
- Crowding causing tooth/teeth to be pushed out of the bony trough, resulting in recession
- Periodontal damage related to traumatic overbits
- Anterior crossbites with evidence of compromised buccal periodontal supported on affected lower incisors
- Increase overjet with increased risk of dental trauma
- Unerupted impacted teeth with risk of pathology
- Crossbites associated with mandibular displacement
dental trauma and orthodontics
Increased overjet is associated with trauma to upper incisors – 2 systematic reviews found risk of injury is more than double in individuals with an overjet greater than 3mm, risk increases with overjet size and lip incompetence
- Increased risk of dental trauma – indicated ortho Tx
Mouthguards – imp in reducing risk of dental trauma esp in contact sports
tooth impactation
when normal tooth eruption is impeded by another tooth, bone, soft tissues or other pathology
supernumerary teeth
cause impaction and if judge to be impeding normal dental development – orthodontic intervention needed
ectopic teeth
that have been formed, or subsequently moved into, wrong position
- Often become impacted
unerupted impacted teeth
may cause localised pathology – commonly resorption of adj roots or cystic change
Most frequently seen in relation to ectopic maxillary canine teeth – can resorb roots of incisors and premolars
uncontrolled caries and orthodontic appliance placement
Caries reduction is rarely an appropriate justification for orthodontic treatment and placement orthodontic appliances with uncontrolled caries risk factors is likely to cause significant harm
when may orthodontic Tx help resolve caries
Malignment in caries suspectable children (e.g. special needs) may reduce capacity for natural tooth cleansing capacity and increase caries risk
Orthodontic solution sought to reduce food stagnation
- Extraction or alignment to alleviate localised crowding
plaque control
if poor contraindication for orthodontic Tx