Impacted teeth - incisors and premolars Flashcards
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
What can be seen here?
an impacted premolar (supplemental)
What may this situation lead to in the long term?
- caries of the impacted tooth via a gingival communication
- caries of the erupted teeth due to difficulty cleaning
- cystic change of the impacted tooth leading to problems such as root resorption of other teeth
Describe the impacted tooth seen in this DPT
impacted mandibular premolar, ectopically placed, intra-osseous
What would the treatment be for the impacted premolar shown here?
free of pathology so would follow conservative management
What would the treatment options for these impacted premolars be?
if hygiene an issue - removal
if hygiene not an issue - conservative
What kind of flap is being shown here?
2-sided flap
What anatomical feature must be carefully thought about when cutting a flap in the premolar region?
mental nerve bundle
Where are supplemental supernumerary teeth commonly found?
palatal in maxilla or premolar/third molar
What are the 3 types of supernumerary teeth?
supplemental, conical, tuberculate
Where do conical supernumeraries commonly erupt?
between central incisors, called mesiodens
What issues may tuberculate supernumeraries cause?
tend not to erupt but prevent eruption of adjacent teeth therefore removal warranted and often performed during incisor exposure
What is this?
mesiodens
What kind of supernumerary teeth can be seen here?
supplemental teeth
What condition can be seen here?
hyperdontia
What are odontomes?
hamartomas, genetic malformations sometimes referred to odontogenic tumours which are entirely benign
What are the 2 forms of odontomes?
complex or compound
What are complex odontomes thought to be formed by?
invaginations of tooth germs therefore disordered dental tissues found in mandibular molar region
Where are compound odontomes more common?
anteriorly
Where are complex odontomes more common?
posteriorly
What % of all odontogenic tumours do odontomes account for?
22%
What do compound odontomes result from?
exuberant proliferation of the dental lamina therefore consists of a number of denticles (look like a bag of small teeth)
What’s the difference between complex and compound odontomes?
complex are disordered formations of dental tissues eg dentine, cementum etc., whereas compound look more like formed teeth
What issues may odontomes cause?
may impede eruption or result in associated pathology, so may require surgical removal
What kind of odontomes are these?
very large complex odontomes, impeding eruption of other teeth
What kind of odontome is this?
compound odontome - can see lots of small calcified structures
