Dental anoamlies Flashcards
4 classes of dental anonamlies
number
size and shape
structure - hard tissue defects
eruption and exfoliation
hypodontia
missing teeth from normal sequence
teeth commonly affected by hypodontia
3rd molars: 9-37% of population have more than 1 missing
1.0.1-0.9% in the primary dentition
4.3.5-6.5% in the permanent dentition
mandibular premolars: 1.2-2.5% (5s)
maxillary lateral incisors: 1.0-2.0% (2s)
The teeth least likely to be missing are the first permanent molars and upper central incisors
*tends to be end of series *
conditions associated with hypodontia
Ectodermal Dysplasia (sparse hair, small nose, sweating)
Down Syndrome
Cleft Palate
Hurler’s syndrome
Incontinentia pigmentii
hypodontia dental management
in chronological order
Diagnosis
Removable prosthesis (waiting to grow, full permanent dentition)
Orthodontics
Composite build ups – inc size and shape
Porcelain veneers
Crowns, bridges and implants – need to wait for gingival margin settle, early/mid 20s
class of preventative tx need for hypodontia pts
high risk as less teeth
enhanced prevention needed throughout life
possible dental issues associated with hypodontia pts
submergence/infraocclusion of permanent teeth
deep overbite
spacing
issues with occlusion - reduced LFH
abnormal shape/form
* cone shaped teeth or straight sided can happen
hypodontia tx aims
3
prevention
aesthetics
function
commmon solutions/tx for hypodontia pts
overdentures
partial dentures
composite additions
porcelain veneers
fixed prosthodontics
example tx plan for hypodontia pt
Local fixed orthodontics to oppose central incisors, and composite build up
Overdenture – restore face height
Implants
Bone augmantation, sinus lift, distraction osteogenesis
hyperdontia/supernumerary
extra teeth to normal sequence
most common hyperdontia/supernumerary
1.5-3.5% prevalence
males:females 2:1
higher frequency in Japanese
more common in maxilla
higher frequency in cleidocranial dysplasia
types of supernumerary
4
Conical (cone shaped)
Tuberculate (barrel shaped, has tubercles)
Supplemental (looks like tooth of normal series)
Odontome (irregular mass of dental hard tissue, compound or complex)
most common cause of delayed eruption of permanent incisor teeth
supernumerary teeth
*Conical supernumerary
Central incisors are at immature stage so wouldn’t go in at this stage
Wait till child is 7/8 then remove extra teeth as root formation of 1s complete *
microdontia
smaller teeth than normal
2.5%
F>M
e.g. peg shaped lateral incisors
macrodontia
bigger teeth than normal
rare
less than 1% for single teeth and 0.1% in generalised form in Caucasians
double teeth
2 types
Gemination (one tooth splits into 2)
Fusion (two teeth join to form 1)
odontomes
anomalies in size and shape
odd dentine/enamel masses
taurodontism
flame shaped pulp, teeth look normal but risk pulp exposure in restorations
6.3% in UK
dilaceration
can be to crown or root
due to trauma or anomaly
accessory cusp
e.g. talon cusp
Selective grinding over time, Fluoride on
Encourage pulp to regress
dens in dente
tooth in tooth
invagination on tooth, seal areas to prevent bacteria ingress as not able to RCT and plaque trap
anomalies in root structure
short root anomaly
* permanent maxillary incisors
* 2.5% incidence
* 15% of these children also have short roots on the canines and premolars
* Danger for orthodontic tx
Causes
* radiotherapy
* dentine dysplasias
* accessory roots
3 enamel anomalies
amelogenesis imperfecta
environmental enamel hypoplasia
localised enamel hypoplasia