Anomalies pt 1

Question 1

what is hypodontia?

Answer 1

developmental absence of primary or permanent teeth

Question 2

what is oligo and anodontia?

Answer 2

oligodontia = >=6 teeth missing (doesn’t include 8s)
anodontia = complete absence of teeth

Question 3

at what stage of tooth development does hypodontia arise from?

Answer 3

initiation

Question 4

what single gene defect causes hypodontia?

Answer 4

MSX1

Question 5

what 5 conditions is hypodontia a symptom of?

Answer 5

ectodermal dysplasia
downs (trisomy 21)
cleft lip/palate
solitary maxillary central incisor syndrome

Question 6

what environmental conditions can cause hypodontia?

Answer 6

severe illness or cancer in early childhood

Question 7

what gender is hypodontia more prevalent in?

Answer 7

females

Question 8

after the 8s, what other teeth more likely affected by hypodontia?

Answer 8

mandibular 2nd premolars
maxillary lat incisors
maxillary 2nd premolars
mandibular central incisors

Question 9

what other anomaly is hypodontia often associated w/?

Answer 9

microdontia

Question 10

what radiograph is first choice for diagnosing hypodontia? if the tooth is ectopic?

Answer 10

PA - but DPT if tooth ectopic

Question 11

ectodermal dysplasia - how is hair, skin, mouth, eyes and nose affected?
how do teeth appear? (3)

Answer 11

group of diseases affecting ectoderm
sparse hair, dry skin, cannot sweat
xerostomia, dry eyes, nasal congestion
conical teeth, micro and hypodontia

Question 12

what stage of tooth development do supernumaries arise from?

Answer 12

initiation

Question 13

where are mesiodens and paramolar supernumaries positioned?

Answer 13

mesiodens = between centrals
para molar = buccal or palatal to molars or between molars

Question 14

explain appearance of conical, tuberculate and supplemental supernumaries - how likely will they impede eruption?

Answer 14

conical = most common, cone shape, unlikely to impede eruption, likely erupts
tuberculate = barrel shaped, do not ususally erupt so likely to impede eruption
supplemental = normal anatomy, unlikely to impede eruption, likely erupts

Question 15

odontome supernumaries - likely to erupt/impede eruption? explain difference between compound and complex.

Answer 15

will not erupt, likely to impede eruption

compound = bag of teeth (denticles)
complex = disorganised collection of tooth tissue

Question 16

what radiographs are used to diagnose supernumaries?

Answer 16

parallax & CBCT

Question 17

what 3 conditions are supernumaries a symptom of?
what gender is most likely affected?

Answer 17

cleidocranial dysostoses
cleft lip/palate
gardener syndrome

male>female

Question 18

cleidocranial dysostoses - what group of conditions? what are absent? what tooth anomaly? what clinical sign?

Answer 18

rare AD condition
hypoplastic or absent clavicles - pt has short stature
supernumary teeth
delayed/failed exfoliation of teeth

Question 19

what stage of development does microdotnia & macrodontia develop?

Answer 19

morphogenesis stage

Question 20

what anomaly is micordontia associated w/? what 2 conditions is this seen in?

Answer 20

hypodontia
ectodermal dysplasia
cleft lip/palate

Question 21

what is most common tooth to be affected by microdontia? how do roots of these present?

Answer 21

maxillary lateral incisors - peg laterals
short narrow root & lack of resoprtion

Question 22

what two features make macrodontia teeth larger than average? what other anomaly is it associated w/?

Answer 22

double tooth or have talons cusp
associated w/ supernumaries

Question 23

double teeth - explain difference between fusion and gemination

Answer 23

fusion - tooth germs join tog, 2 roots on radiograph
gemination - one tooth completely divided, 1 root on radiograph

Question 24

what is dens invaginatus? what stage of tooth development does it occur?

Answer 24

enamel has folded within itself creating an enamel lined cavity
“tooth within a tooth”
morphogenesis

Question 25

what teeth most commonly affected by dens invaginatus? what is a noticeable feature on these teeth?

Answer 25

1. maxillary lateral incisors 2. maxillary centrals pronounced cingulum pit

Question 26

what may the first indication of dens invaginatus be?

Answer 26

random loss of vitality in absence of trauma/caries

Question 27

how do you manage dens invaginatus?

Answer 27

fissure seal cingulum pits RCT when loss of vitality XLA or referral if RCT too complex

Question 28

Dens exvaginatus - known as, what stage of root development, what teeth most common

Answer 28

"talons cusp" morphogenesis maxillary incisors

Question 28

how does dens exvaginatus present on premolars? what may happen to tooth in long term?

Answer 28

central talons cusp worn down area of cusp may expose dentine and lead to loss of vitality

Question 29

how does dens exvaginatus present on incisors?

Answer 29

palatal cusp

Question 30

how do you manage dens exvaginatus?

Answer 30

OHI & fissure seal gradual reduction/grinding of cusp to encourage reactionary dentine formation - prevents pulpal exposure OR remove cusp, pulp cap & pulpotomy/RCT

Question 31

what is dilaceration? what usually & rarely causes it? what teeth are most commonly affected?

Answer 31

bend in root or crown usually acquired defect - due to trauma to primary tooth affecting permanent rarely caused by pathology maxillary centrals most commonly affected

Question 32

give 3 clinical signs of crown dilaceration - what radiographs to investigate? (2)

Answer 32

failed eruption altered path of eruption ectopic position lat cephalogram, CBCT

Question 33

taurodont appearence - pulp chamber, bifurcation, roots, crown

Answer 33

elongated pulp chamber in a multi rooted tooth low bifurcation short roots normal looking crown

Question 34

what classification classes taurodonts? give 4 classifications

Answer 34

shaw classification normal>hypotaurodont>mesotaurodont>hypertaurodont

Question 35

what stage of root development does taurodontism occur?

Answer 35

morphogenesis

Question 36

what 3 conditions is taurodontism associated w/?

Answer 36

amelogenesis imperfecta trisomy 21 (down's) Klinefelter

Question 37

how do short roots present clinically?

Answer 37

mobile no response to sensibility test if cause due to loss of vitality may have microdontia and enamel defects where cause childhood illness

Question 38

what genetic condition causes short roots?

Answer 38

dentine dysplasia

Question 39

list environmental reasons short roots may occur

Answer 39

loss of vitality prior to apexogenesis illness (cancer) ot treatment during root formation traumatised tooth, ortho treated, ectopic teeth, pathology

Question 40

how do you manage short roots in vital and non vital teeth?

Answer 40

non vital teeth - RCT w/ apexification vital teeth - no intervention, plans made for eventual loss