Chapter 11: Dental Anomalies Flashcards
1
Q
5 different classifications of dental anomalies are:
A
- number anomalies
- size anomalies
- shape anomalies
- color anomalies
- structure anomalies
2
Q
What type of anomaly does this statement describe?
“ they occur in the earliest periods of development (Dental lamina disorganisation)”
A
Number anomalies
3
Q
The two types of number anomalies are:
A
Agenesis and supernumerary
4
Q
Agenesis: classification from more severe to less severe
A
- anodontia: the total absence of the tooth germ
- temporary teeth: agenodontia
- permanent teeth: ablastodontia
- oligodontia: half or more of the tooth germs are missing
*10 or fewer teeth germs are present in primary dentition (instead of 20): oligogenodontia
*16 or fewer teeth germs are present in permanent dentition (instead of 32): oligoblastodontia - hypodontia: less than half of the tooth germs are missing
- less than 10 primary teeth are missing: atelogenodontia
- less than 16 permanent teeth are missing: ateloblastodontia
5
Q
Agenesis: frequency
A
- more frequent in permanent teeth
- more frequent in females
- 75% of patients with agenesis in temporary teeth will have agenesis in permanent teeth
6
Q
Agenesis: location
- in temporary teeth it’s more common in the ___ (maxilla/mandible) and is usually ____ (bilateral/unilateral) and in these teeth ____
- in permanent teeth it’s more common to affect ___ (more teeth/one tooth), and is usually ___ (bilateral/unilateral) and in these teeth _____
A
- maxilla, unilateral, upper LI, lower CI, lower LI
- more than 1 tooth, bilateral, 3rd molars, upper LI, 2nd lower PM, 2nd upper PM, lower CI (in that order)
7
Q
Agenesis: aetiology
A
- By a physical obstruction at the dental lamina (oral-facial-digital syndrome)
- functional abnormalities of the dental epithelium ( ectodermal dysplasia)
- bud developers but there is no induction of the mesenchyme
- space problems
- non syndromic agenesis: genes MSX1, PAX8, and AX1N2
- drugs (thalidomide)
- infections: rubella in the mother
- radiotherapy in children
8
Q
Agenesis: diagnosis
- clinical
- radiographical
A
- clinical: absence of a tooth for around 1 year—> suspected diagnosis
- radiographical: absence of 2nd PM at 9-10 years old
9
Q
Agenesis: treatment (multidisciplinary)
A
Orthodontic, prosthetic, or restorative
10
Q
Supernumerary (hyperdontia): frequency
- infrequent in ?
- more frequent in ____ (boys/girls)
- more frequent in ?
A
- infrequent in temporary and permanent dentition (1-4% of the population)
- more frequent in boys
- more frequent in upper incisors
11
Q
Supernumerary (hyperdontia): aetiology (different theories)
A
- hyperactivity of dental lamina
- tooth germ division
- hereditary (especially in syndromes)
12
Q
Supernumerary (hyperdontia): classification according to the morphology
A
- supplemental: similar to the adjacent, normal shape, most common in permanent upper LI
- rudimentary: different to the adjacent, (short-barrel shaped —> palatal to upper CI
most common shapes: - tuberculate (short barrel shaped): palatal to upper CI, unilateral or bilateral
- conical shaped (peg- shaped): most typical is mesiodens
13
Q
Supernumerary (hyperdontia): classification according to the location
A
- mesiodens: between upper CI, single or multiple, variable size and shape but typically conical rudimentary, can be suspected when there’s an asymmetry in the eruption of the CI
- paramolars: extramolars
- distomolars: distal to 3rd molars
- peridens: premolar area
14
Q
Supernumerary (hyperdontia): alterations caused by mesiodens
A
- eruptive delay
- deviation of the permanent successor teeth or adjacent tooth
- root resorption by contact
- radicular cyst formation
- eruption in nostrils
- sometimes causes diastemas
15
Q
Supernumerary (hyperdontia): diagnosis and treatment
A
- always radiographic
- extraction and orthodontic treatment
16
Q
Which type of anomaly does this statement describe?
“ they are produced in the morphodifferentiation period of germs”
A
Size and shape anomalies
17
Q
Size anomalies: classification
A
- macrodontia
- microdontia
- rhizomegaly
- rhizomicry
18
Q
Size anomalies: bigger than normal anomalies
A
- macrodontia
- rhizomegaly
- fusion
- germination
19
Q
Size anomalies: macrodontia aetiology
A
- hereditary associated with endocrine disorders
- generalised form associated with congenital syndromes
20
Q
Size anomalies: macrodontia frequency
A
- more in permanent teeth
- upper CI, C, M
21
Q
Size anomalies: rhizomegaly frequency
A
Lower permanent canines and molars
22
Q
Size anomalies: fusion
A
- F22
- joining of 2 teeth germs that gives rise to a single larger tooth
- it can have 1 or 2 pulp chambers
- different than macrodontia because there’s a tooth missing in the arch
23
Q
Size anomalies: fusion frequency
A
- autosomal dominant inheritance
- more frequent in primary teeth in the anterior area
- if we see fusion in primary teeth, there is often agenesis of 1 of the 2 permanent successors
24
Q
Size anomalies: germination
A
G12
- an incomplete division of a germ resulting in an abnormally large tooth
- 1 root and 1 canal
- common in anterior sector of the maxilla
- differs from fusion because the number of teeth in the arch is not altered
25
Size anomalies: smaller than normal anomalies
- microdontia
- rhizomicry
26
Size anomalies: microdontia
- due to the weakening of the enamel organ during differentiation
- generalised clinical forms are rare and are usually associated with different diseases (Down syndrome, pituitary dwarfism, antihydrotic ectodermal dysplasia)
27
Size anomalies: microdontia frequency
- most frequently localised and bilateral
- most affected tooth: maxillary LI
28
Size anomalies: rhizomicry
- mainly in?
- frequent with which diseases?
- mainly in CI and 3rd molars
- frequent in osteopetrosis —> generalised rhizomicry
29
Size anomalies: treatment
- 2 main problems
- macrodontia treatment
- microdontia treatment
- space and aesthetics
- macrodontia: lack of space and malocclusion: Ortho
- microdontia: multiple diastemas, if many teeth affected: prosthetic, if few: CR restoration
30
Shape anomalies: types
- dens evaginatus (Talon cusp)
- dens in dente
- taurodontism
- cynodontia
- dilaceration
- radicular divergence
- radicular convergence
- pyramidal root
- enamel pearl
- accessory root
31
Shape anomalies: dens evaginatus (talon cusp)
- a tooth with an extra cusp or tubercle
- frequency form more to less: I, C, PM, M
32
Shape anomalies: dens evaginatus treatment
Not necessary unless the occlusion is affected, in that case:
- We carve the tubercle carefully because the pulp extension can exist, and the root canal treatment could be necessary if a pulp exposure takes place
- Caries are frequent in the groove surrounding these tubercles—> conservative treatment (it is advisable to do sealants)
33
Shape anomalies: dens in dente aetiology
Invagination of the inner enamel epithelium during tooth formation
34
Shape anomalies: dens in dente frequency
- in permanent teeth
- most affected teeth: upper LI, CI, C , supernumerary (unilateral)
- there might be contact between the pulp and oral environment
35
Shape anomalies: dens in dente treatment
- as the pulp communicated with the oral environment, we have frequent early pulpitis —> pulp treatment
- if pulp treatment fails, extraction
36
Shape anomalies: taurodontism
- only molars are affected
- larger crowns and shorter roots
- elongated pulp chamber and the furcation is shifted towards apical compared to a normal tooth
- no clinical disturbance, radiographic diagnosis
37
Shape anomalies: taurodontism frequency
- both dentitions can be affected, more common in permanent teeth
- generalised may be associated with 2 syndromes: tricho dento osseous syndrome and orodigitofacial syndrome
38
Shape anomalies: taurodontism treatment.
- No treatment is needed, but the diagnosis is useful
- It is useful to know if we ever need to do a pulp treatment (important to know
that the anatomy is different: large pulp chamber and short roots)
39
Shape anomalies: cynodontia
- The converse situation of taurodontism
- Due to the early invagination of Hertwig’s epithelial root sheath
- Short crowns with short pulp chambers and long roots
- The furcation will be located more occlusal
- More often in permanent molars
- No treatment is required but its diagnosis is useful
40
Shape anomalies: dilaceration
- Abnormal root curvature at the level of the crown-radicular union
- A variant of dilaceration is root angulation when the curvature occurs at any point of the root and bayonet root which is a double angulation.
- aetiology: Thought to be due to trauma in primary teeth (incisors intrusion)
41
Shape anomalies: radicular divergence
Teeth having a steeper divergence than normal
42
Shape anomalies: radicular convergence
- The opposite of divergence
- If convergence is so big that the roots are joined—> synostosis
- The roots are joined in their apical portion by apposition of secondary cement
43
Shape anomalies: pyramidal root
- Molar having a single root (when it should have multiple)
- 2nd and 3rd molars
44
Shape anomalies: enamel pearl
- Enamel formations, rounded, in locations where the enamel is not supposed to be
- Usually in furcation of molars
- Where the pearl is formed there is no cement, the enamel is deposited directly into the dentin
45
Shape anomalies: enamel pearl aetiology
- Atrophic supernumerary tooth germs
- Groups of hypertrophic ameloblasts
46
Shape anomalies: accessory roots
- They exceed in number and can have a normal shape or as appendices
47
Color anomalies: when do intrinsic stains occur ?
During tooth development, pigments are included in the structure of the tooth, they’re difficult to remove
48
Color anomalies: intrinsic staining: tetracycline staining:
- Due to the administration of tetracycline in periods of enamel and dentin mineralisation
- Tetracycline binds to Ca molecules and remains attached to dental tissue
- Tetracyclines can cross the placental barrier, so the temporary teeth could be affected if taken by the mother during pregnancy
- Colour: from yellowish to dark grey, with diffuse bands of different widths at different levels of the crown
- Location of the band: depends on the moment of the development of the tooth at the time of the administration of the drug
49
Color anomalies: intrinsic staining: tetracycline staining critical periods
- from the 4th month of gestation to the 9th month after birth (primary dentition)
- from birth to 7-8 years old (permanent dentition)
50
Color anomalies: intrinsic staining: dental fluorosis
- Due to the systemic administration of more than 1.8 ppm of fluoride per day
- The degree depends on the moment of the development of the enamel and dentin, and the magnitude of the ingestion
- Colours range from chalk white to brown
- In severe cases, there are structural defects (hypoplasia and hypocalcification of the enamel)
51
Color anomalies: intrinsic staining: staining by blood pigments
- In children with blood disorders that lead to hemolysis and release blood pigments, which bind to enamel and dentin in formation
52
Color anomalies: intrinsic staining: staining by blood pigments is caused by?
a. Congenital erythropoietic porphyria
b. Fetalerythroblastosis
c. Post-transfusional hemolysis
d. Congenital hyperbilirubinemia
53
Treatment of intrinsic staining?
It depends on the degree of alteration (intensity and number of affected teeth)
- Mild pigmentation in a few teeth—> restoration with composite resins
- Severe and extensive pigmentation—> porcelain veneers or crowns
54
Color anomalies: extrinsic staining
- Outside the dental structure, and lies on tooth surface or in acquired pellicle
- Plaque deposits with chromogenic bacteria
- More common: deposits of ferric compounds, excess food, or pigmented drinks
- Incorporated into the surface of the teeth once the tooth finishes its formation
- Eliminated with a correct brushing or professional cleaning (dental scaling or dental hygiene)
55
Structure anomalies: enamel anomalies
- quantitative
- qualitative
- two types
- Quantitative defects: hypoplasia
- Qualitative defects: hypomaturation, hypocalcification, MIH (molar-incisor
hypomineralisation)
- Enamel anomalies are either:
a. Hereditary enamel disturbances: amelogenesis imperfecta
b. Acquired enamel disturbances: due to general or local factors
56
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta:
- The main hereditary enamel disturbance
- Alteration in the calcification of the enamel due to an abnormal function of ameloblasts
- Both dentitions may be affected
- Frequent anterior open bite
- Low caries due to few interdental contacts
57
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta: 3 types
a. Hypoplasia: quantity is affected
b. Hypomaturation: quality is affected
c. Hypocalcification: quality is affected
58
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta: hypoplastic type:
- Quantity: reduced enamel thickness but relatively well-mineralised
- Both dentitions are affected (temporary and permanent)
- Altered colour of the enamel from yellowish to dark brown
- Hard consistency
- Dentin hypersensitivity: 60% lingual interposition with open bite
59
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta: hypomaturation type:
- Both dentitions are affected
- The final stage of the mineralisation process is abnormal
- The quality of the enamel is affected, and the mineral context of the enamel is altered
- The enamel is brittle, porous, very permeable, and rough
- Colour from white to brown and tends to fall off easily
- Many subtypes, one of them is “snow-capped teeth”: white spots on incisal edges and the buccal surfaces near the occlusal surface
- X-ray observation: no contact points, lost enamel
60
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta: hypocalcified type:
- The quality of the enamel is poor as calcification of the interprismatic substance of the matrix is altered, instead of the mineral content (hypomaturation type)
- The enamel formed in adequate amounts, but poorly calcified: fragile, easily detaching, exposing the dentin
- Radiographically: the dentin is usually more radiopaque than the enamel
- Clinically: cannot be differentiated from the hypomaturation type
61
Structure anomalies: enamel anomalies: hereditary enamel disturbances: amelogenesis imperfecta: treatment
- Objective: to prevent teeth from breaking, suppress sensibility and achieve aesthetics and prevent caries
- Oral hygiene techniques
- Fluoride (that hardens the enamel)
- Composite restorations and crowns (need to be changed very often because the adhesion is very bad)
- If left untreated: may have sensitivity and might need pulp treatments
- Severe cases end up needing prosthetic restorations
62
Structure anomalies: enamel anomalies: acquired due to general or systemic causes: neonatal disorders
- Hypoxia
- Hypocalcemia
- Premature birth
- Stress at birth: neonatal lines or Retzius lines in the temporary dentition
63
Structure anomalies: enamel anomalies: acquired due to general or systemic causes: nutritional deficiency:
- Hypovitaminosis A, C, D, K
- Deficiency of Ca and P
- Teeth appear with horizontal rows that coincide with the matrix area formed
at the time of vitamin deficiency
- The extension depends on the duration of the process/deficiency
64
Structure anomalies: enamel anomalies: acquired due to general or systemic causes: maternal diseases
- Maternal diabetes: frequency of dysplasia in temporary teeth
65
Structure anomalies: enamel anomalies: acquired due to general or systemic causes: severe postnatal diseases
- With high fevers (febrile hypoplasia)
- Exanthematic diseases: chicken pox, measles, salmonellosis
- Neuropathies
- Congenital alterations of the metabolism
- Due to some diseases like asthma
66
Structure anomalies: enamel anomalies: acquired due to general or systemic causes: prenatal infections
- Congenital syphilis: enamel and dentin hypoplasias
- The permanent maxillary incisors have spots and are pyramidally shaped (Hutchinson’s teeth) and mulberry molars
- Rubella in the first trimester of pregnancy: affects the temporary dentition
67
Characteristics of acquired enamel anomalies due to general causes:
- Enamel defects due to systemic causes are characterised by their tendency to symmetry and by affecting the same dental groups
- We try to relate the time of the cause with the teeth that have had the malformation
- Once the tooth is formed with the stain, preventive treatments are not a solution
68
Structure anomalies: enamel anomalies: acquired due to local causes: radiation
pregnant women undergoing radiation therapy
69
Structure anomalies: enamel anomalies: acquired due to local causes: apical infections
from temporary to permanent teeth.
The temporary tooth damaged at the apical level produces a spot in the permanent tooth (Tumer’s tooth) from temporary to permanent teeth.
70
Structure anomalies: enamel anomalies: acquired due to local causes: iatrogeny
in patients with cleft lip or pathologies requiring surgical treatment that may affect the dental germ
71
Structure anomalies: enamel anomalies: acquired due to local causes: maxillary infections
maxillitis or osteomyelitis
72
Structure anomalies: enamel anomalies: acquired due to local causes: trauma
when the temporary teeth impact with the next permanent germ (diente de Carlos)
73
Treatment of acquired enamel anomalies:
- Application of fluoride
- Restoration with composite resins
- in some cases, performed crowns
74
Dentin anomalies: hereditary: dentinogenesis imperfecta
- An inherited disorder affecting dentin with defective dentin
- Autosomal dominant inheritance
- Both dentitions are affected
- The deepest dentin (closest to the pulp) is more affected
- 3 types (according to Shields): type I, II and III
75
Dentin anomalies: hereditary: dentinogenesis imperfecta features
- Bulbous crowns (very rounded)
- Short roots
- Small or obliterated (nonexistent because filled with dentin) pulp chamber and narrow or non-existent canals
- No sensitivity
- Vertical dimension is lost very soon → one of the objectives of the treatment is to preserve the vertical dimension
76
Dentin anomalies: hereditary: dentinogenesis imperfecta type I:
- Always associated with osteogenesis imperfecta
- All teeth in both dentitions are affected
- The teeth have an amber colour, are soft and have frequent fractures
77
Dentin anomalies: hereditary: dentinogenesis imperfecta type II or hereditary opalescent dentin:
- Both primary and permanent dentitions are equally affected
- Translucent bluish-brown colour
- Rapid wear and loss of vertical dimension due to abrasions
78
Dentin anomalies: hereditary: dentinogenesis imperfecta type III or Brandywine Maryland:
- Rare
- Shell-like appearance, very fragile and multiple pulp exposures
79
Dentin anomalies: hereditary: dentin dysplasia:
- A rare group of dentin alterations
- Autosomal dominant inheritance
- Affects the dentin next to the pulp and the root
- 2 types: type I and II
80
Dentin anomalies: hereditary: dentin dysplasia: type I or radicular dentin dysplasia
- Crown: normal colour and shape in both primary and permanent dentitions. Only affects the root (both dentitions)
- Root: tends to be short or absent. Obliterated pulps and multiple periapical radiolucencies (X-ray)
81
Dentin anomalies: hereditary: dentin dysplasia: type II or coronal dentin dysplasia:
- Root: normal
- Pulp chamber: altered
- Obliterated pulp chambers in temporary teeth, thistle shape in permanent teeth
- Amber teeth
- Sometimes: pulpitis (calcifications, X-ray)
82
Dentin anomalies: acquired
All are due to systemic factors:
- Nutritional deficiency (hypovitaminosis A, C and D)
- Alterations in metabolism
83
Enamel and dentin anomalies: odontogenesis imperfecta:
- Hereditary
- Linked to osteogenesis imperfecta and enamel disorders
- Clinically: type I dentinogenesis and enamel hypoplasia
84
Enamel and dentin anomalies: regional odontodysplasia (ghost teeth):
- Localised dentition of the development of the enamel and dentin in a particular tooth
- X-ray observation: normal teeth and some are blurred with very large chambers and short roots
- Early loss
- Does not trespass the midline
85
Cementum anomalies: hereditary: hereditary cementosis:
- Autosomal dominant inheritance
- Radiographic diagnosis: usually casual when observing periapical diffuse radiopaque masses
86
Cementum anomalies: hereditary: cleidocranial dystosis:
- Autosomal dominant inheritance
- Cement dysplasia
- Delayed eruption and supernumerary
87
Cementum anomalies: hereditary: hypophosphatasia
- Autosomal **recessive** inheritance
- Inability to produce alkaline phosphatase
- 3 clinical forms: infantile, juvenile, adult
- The cementum is not formed so the tooth has mobility and early exfoliation (periodontal problems)
88
Cementum anomalies: acquired: concresence:
- The union of 2 or more teeth by root cementum
- True concrescence: occurs when the teeth are forming (typically between the 2nd and 3rd molars)
- Acquired: produced by hypercementosis secondary to local factors, trauma, or mechanical pressure
- Also, in Paget’s bone disease (due to hyperproduction of cement)
