Impacted teeth - incisors and premolars Flashcards
(49 cards)
What is the third most commonly impacted tooth?
maxillary incisors
For what reasons would delayed eruption require monitoring or investigations?
- if contralateral teeth erupted 6/12 previously or in the case when both upper centrals missing one year after eruption of lower incisors
- deviation from normal sequence of eruption i.e. laterals before centrals
What are the hereditary causes for delayed incisor eruption?
- supernumeraries
- cleft lip/palate
- cleidocranial dysostosis
- odontomes
- abnormal tooth /tissue ratio
- gingival fibromatosis
- generalised retarded eruption
What are the environmental causes for delayed incisor eruption?
- trauma= root dilaceration
- early loss or extraction of deciduous tooth
- retained deciduous tooth
- cyst formation
- endocrine abnormalities
- bone disease
If a patient presents with delayed incisor eruption, what should you do?
- history and examination
- look for:
- retained deciduous teeth (if not mobile indicates lack of root resorption)
- palpable buccal/palatal mass
- lack of space
- erupted mesiodens/supernumeraries
- radiography - parallax
What are the 3 most common ways of managing an incisor impaction?
interceptive, exposure, or removal
What would interceptive management of incisor impaction involve?
removal of retained deciduous teeth if they are impeding eruption of the permanent incisor
When would an impacted incisor be managed by removal?
if severely dilacerated
If an incisor was impacted and the deciduous tooth was removed, what would need to be done after its removal?
create and maintain space - 75% erupt spontaneously, 55% align spontaneously
If a supernumerary tooth was impeding eruption of an incisor, what would be done?
remove other obstructions and expose the incisors surgically, 50-75% erupt in 16 months, may require brackets to align
Where are impacted incisors typically positioned?
labially
What is the open technique of incisor exposure?
flap raised taking as much attached gingivae as possible and repositioned apically and packed
involves removal of bone/fibrous tissue to exposure maximum convexity of tooth
What is the closed technique of incisor exposure?
raising a flap, removing bone/fibrous tissue to expose maximum convexity of tooth, and attaching bracket and gold chain before suturing the flap back over
What can be seen here?
conical supernumerary which is delaying the eruption of the central incisor
What does this show?
conical inverted supernumerary tooth which has caused rotation of the central incisor which can’t be corrected orthodontically until the supernumerary is removed
What is this showing?
open technique - apically repositioned flap for incisor exposure, 3 sided flap
When may the open technique for incisor exposure be advocated?
when the impacted incisor is very superficial/close to where it should be
What technique of impacted tooth exposure leads to better gingival aesthetics?
closed technique
What is this showing?
closed technique - 3 sided flap, overlying bone etc removed, orthodontic brackets and gold chains applied
What is the 4th most commonly impacted tooth?
mandibular premolars
What are the potential causes of mandibular premolar impaction?
crowding, pathology, ankylosed deciduous tooth, supernumeraries, genetic disorders
Where are mandibular premolars usually displaced?
usually lingual displacement palpable clinically
What is the incidence of mandibular premolar impaction?
0.2-0.3%
What is involved in the removal of mandibular premolars?
removal required buccal flap, avoiding damage to mental bundle, elevate or section tooth to remove as a traumatically as possible
removal of adjacent premolar may be preferred
