Delayed Eruption MFDS WoS - PowerPoint Presentation

Slide1

Delayed Eruption

MFDS

WoS

Study Group 

August 2021

Delayed Eruption

Know the eruption dates approximately, but most important is the

sequence

of eruption. If tooth fails to erupt

within 6 months

of its antimere, or there is a significant deviation from the normal sequence (e.g. a 2 erupting before a 1), investigate. In Part 2

MFDS

you may be given a cephalogram or OPG of a child with delayed eruption and be expected to realize that there is something wrong!

Aetiology (local factors)

Absence- v unusual in a central, more common with maxillary laterals, and 5s.

Crowding

Delayed exfoliation of primary tooth

Supernumeraries

Odontomes- a benign tumour of odontogenic origin

Pathology- e.g. cyst

Dilacerations- may be developmental or as result of trauma.

Abnormal position of crypt e.g. ectopic canines

Impaction- usually because of crowding

Retained primary teeth- ankylosed

Premature loss of primary teeth- leading to bone deposition/gingival hypertrophy??

Primary failure of eruption- usually confined to buccal segments and very rare- failure of the eruptive mechanism due to ankylosis and infraocclusion is a secondary failure of eruption

Aetiology (systemic factors)

Cleidocranial dysostosis— a disorder of bone leading to delayed eruption and multiple supernumeraries

Hereditary gingival fibromatosis

Down’s syndrome

CLP

Hypothyroidism

Hypopituarism

Hypoparathyroidism

Gardner’s syndrome- bowel polyps (premalignant). Boney osteomata and soft tissue tumours

Von Recklinghausen’s neurofibromatosis

Aetiology (Cont’d)

MEDICATION (rare):

Those which cause gingival overgrowth- e.g. phenytoin, ciclosporin, calcium channel blockers (commonly Amlodipine)

Supernumerary Teeth

Additional to normal series. 2% of permanent dentition, 1% of primary. More common in males than females. Also commonly found in cleft palate.

-Conical (mesiodens)- conical or peg-shaped, most commonly between upper centrals. Often cause a median diastema

-Tuberculate (barrel shaped)- associated with failure of eruption.

-Odontome- rare.

Complex

and

compound

types.

 NB The presence of a

supernumerary is the most common reason for failure of eruption of maxillary central

, but failure of eruption could be caused to any tooth by a supernumerary.

Dilacerations and Odontomes

Dilacerations are developmental in 70% of cases, most commonly in females with no history of trauma. May also arise due to cysts or supernumerary teeth in 7% of cases, or secondary to trauma to the primary dentition in the remainder- usually in boys.

Odontomes- thought of as supernumeraries- hamartomatous malformations that may be

complex

or

compound

(resembling a collection of tooth tissue).

Infra-occlusion

Caused by ankylosis.

Suspect missing teeth if deciduous tooth is retained. It is common to see infra-occlusion of second deciduous molar if premolar is missing. Infraocclusion has been reported at 55%, with up to 8.3% suffering significant infra occlusion.

Early extraction may be indicated if wishing to preserve vertical bone height.

If retaining an infraoccluded tooth, it can be built up with composite or an

onlay

(e.g. E-max) to maintain occlusal height and avoid over-eruption of opposing teeth/tipping of adjacent teeth.

Ectopic Canines

1.5% of the population. 10% are bilateral. MOST are

palatally

placed.

37% of patients with palatally-displaced canines have missing or diminutive laterals or absent second premolars. If canines are not palpable by 10 to 11 years old, radiographic examination should be carried out, and patient should be referred if concerns regarding position. Do not wait too long!

Localisation

- parallax radiographs

Treatment options:

A) Extraction of the C

B) Surgical exposure & orthodontic alignment

C) Surgical removal of impacted canine

D) Transplantation

E) No active treatment/leave and observe

Management of Delayed Eruption (Incisors)

Removal of obstruction

: 90% of impacted incisors will erupt within 18 months of removal of a supernumerary.

Most incisors will align spontaneously, but 34% require orthodontic alignment

Surgical intervention

: open or closed exposure and bonding of gold chain

Extraction

: if severely dilacerated (obviously a last resort option)