Eruption Considerations

Chapter 9, pp 184-201; Chapter 27, pp 627-669; McDonald

2

OverviewReview of spacingReview of space maintenance Local and systemic factors that influence eruption:

HabitsEctopic EruptionImpacted and Supernumerary teethAbnormal Labial FrenumAgenesis of TeethAnkylosed TeethEctodermal dysplasiaOther causes: Clefts, Cherubism, hypophosphatemia, acrodynia, Achondroplastic dwarfism,Cleidocranial dysplasia, Hypothyroidism, Hypopituitarism, Down, genetics,

post natal environment/nutrition, trauma, abcesses, early

losses, etc.

3

Review of spacing: Primary dentition

Interdental spacing-spacing between mesial of canines (across labial surfaces of anterior teeth)Accommodates larger permanent teeth

Primate space-between Mx canine and lateral Md canine and 1st molar

Closed primate space-no space availableSecondary incisor space-created by Md laterals forcing

primary Md canines laterally, which forces Mx canines laterally and widens the Mx intercanine arch length.Premature loss Md canines/caries/disking—borderline cases become extraction cases.

Leeway space—(Primary canines’+ Primary molars’ widths)- (Permanent canines’+Premolars’ widths) in each arch

Mx-3.4 mm/arch Md 0.9 mm/arch (large primaries)

4

Review of space maintenance

Band and Loop—unilateral/bilateralBilateral-appliance of choice mixed dentition

need 4 Md incisors/1st molars saves leeway spaceDistal shoe (contraindicated for poor oral hygiene,

blood dyscrasias, immunosuppressed, congenital heart defects, rheumatic fever history, diabetes, debilitation)—chronic inflammation with it--may want to regain space later, instead

RPD/fixed appliances—anterior collapse/space loss preventionreestablish anterior function/speech

5

Habit considerations

0-1 yo—clinging and oral habits

Compulsive habits—fixated

insecure/threatened

Damage from habits-duration

frequency

intensity

6

Thumbsucking

Incidence—47%

no residual effects if eliminated before mixed dentition

(6yo/school age)

Removable digital sucking appliance resembles a Hawley

If pt presents with thumbsucking habit, open bite/posterior X-bite refer for orthodontics (treatment may include Quad hexix)

7

Tongue Thrust/Infantile/Juvenile swallow

Infantile swallow—suckling associated with nursing, training cups

Usually adult swallow by age 6

The tongue can malpose teeth if the swallowing involves the tongue touching the Mx incisors

*Try muscle retraining first—practice placing tongue on incisive papilla and swallow

A tongue thrust appliance helps train the tongue to its proper position

8

Activity: Evaluate space maintenance/guidance/habit sample appliances brought to class

9

Ectopic eruptionAbnormal eruption positionIncidence: 3%, (boys more often)Common Sites:

Permanent Mx 1st molars Permanent Md laterals

Self corrects: 66% of molarsDX: evaluate radiographs closely TX for molars:

1. Monitor (usually lack of tuberosity development)2. Determine it is reversible (self-correcting)/irreversible between 7-8y3. If it is irreversible: orthodontic consult stating concerns/distally reposition it

McDonald 663 27-47

10

Ectopic eruption

Higher incidence-pts with Cleft lip and palate

Self correction rate-22% with a cleft

11

                                                          

  

Ectopic eruption

Location: more frequently Mx

Refer for orthodontic consult for an ectopic molar to distalize it

Include your evaluation of dental age, eruption problems, anomalies, concerns, copy of radiographs

12

Treatment of Ectopic eruption of a permanent first molar

Kesling spring (separator)

Prepare brass wire with double helix bend. Place active spring below contact of the primary 2nd molar and ectopic permanent molar.

TX time—3-4 weeks

McDonald 665 27-48

13

Treatment of Ectopic eruption of a permanent first molar with Kesling spring

Personal collection of Dr. Mike Bagby

14

Alternate Treatments of Ectopic eruption of permanent first molar

Pulpotomy on 2nd primary molar

Reshape 2nd primary molar

Place small SSC on 2nd primary molar which will direct the permanent molar into position

15

Ectopic eruption of permanent lateralsProblem: ectopic permanent Mx/Md

lateral can cause premature primary canine loss (7y)

Serious problem: ectopic permanent Mn lateral can cause premature primary canine and 1st primary molar loss with transposition of permanent lateral/canine

DX: Obtain/review appropriate radiographs

TX: Unilateral condition, no midline shift: space maintenance Unilateral condition, midline shift, crowding, loss of 1 primary canine: orthodontic consult extract contralateral canine passive lingual arch McDonald 666 27-50

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Delayed eruption/ectopic/impacted Permanent canines

Prevalence: 3rd molars—most commonly impactedMx canines-2nd most commonly impacted

Cause: long developmentdubious courseeasily deflected

Dx: evaluate canine crypt; radiographs (8y)

Tx: orthodontic consultation and surgical intervention

McDonald 666 27-50

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Supernumerary teeth causing ectopic eruption

Cause: Continued budding of enamel organ;familial

Incidence: 1/110Prevalence:Mx:Md 8:1Most common: mesiodensProblem: ectopic eruption

or prevention of eruption of adjacent teeth McDonald 667 27-54

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Supernumerary: Mesiodens

Location: most are palatal (von Arx et al., 1992)

DX: review radiographs (occlusal)at age 5-6

Presentation- Abnormal central diastema Abnormal tooth eruption Abnormal occlusion Cystic degeneration (Huang et al,

1992)

Supernumerary primaries

McDonald 667 27-52

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Supernumerary:MesiodensTreatment:

If no interference with other teeth and no indication of cyst:

Delay extraction until permanent teeth erupt and root closure is complete/child is older

If delayed eruption of incisor:

Extract mesiodens

Remove bone & soft tissue from incisal 1/3 of delayed teeth unless the teeth are very high—watch/wait

Maintain/open pathway if possible

Scar tissue can halt eruption McDonald 667 27-54

20From Creighton University

Multiple mesiodens in a 3yo at 4yo no tx Surgery

indicated

21

Multiple wisdom teeth

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Anterior Diastema

Postpone until complete eruption of canines unless:

1. laterals are erupting lingually and do not have space to be moved labially; 2. heavy labial frenum—close the space, then do surgery;

3. Other valid reason

23

Abnormal labial frenum

Labial frenum: 2 layers of epithelium with a loose vascular connective tissue and muscle fibers from the orbicularis oris

Origin: midline on inner lip (wide)Insertion: midline in outer layer

periosteum and CT of internal MX suture and alveolar process to: above the crest of the ridge, or

at ridge, or through centrals to palatine

papilla McDonald 142 7-49

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Abnormal labial frenumWNL (within normal limits): midline

diastema in pre-school children. Diastema usually closes when canines erupt.

Diagnostic test in mid-late mixed dentition:Press on frenum then identify location of alveolar attachment—a blanching of the palatine papilla indicates abnormality.

Other concerns:Interference with speechInterference with eatingDifficulty brushing

McDonald 142 7-49

25

Abnormal labial frenumFrenectomy: Orthodontic consult Evaluate esthetics/function Possible laser surgery Traditional surgery: Do not disturb mesial of free marginal tissue of incisors. Remove wedge section of tissue between incisors to nasal palatine papilla (transeptal fibers). Lateral incisions on either side of frenum to bone. con’t

26

Abnormal labial frenumFrenectomy con’t:

Excise the tissue.

Recontour labial and/or palatal gingival papilla if there is excessive tissue

Do not remove mesial free gingiva

Suture inside the lip to approximate free tissue margins

27

Agenesis of Teeth-failure of teeth to form

Anodontia – all teeth fail to developHypodontia–1 or more teeth fail to

formOlder term: Oligodontia – oligo-few; few teeth presentInaccurate older terms: Congenitally absent-permanent teeth are not expected at birth Partial anodontia-anodontia is complete absence; how does one have a partial complete absence?

Absence of teeth may be: Nonsyndromic/syndromic

One syndrome is Ectodermal Dysplasias

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Anodontia

Autosomal recessive

No permanent dentition

The primary dentition is usually not affected

Treatment :

Overlay denture

McDonald 130 7-37

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Hypodontia Most common: 3rd molarsMost common in children:

Md 2nd premolars Mx lateral incisors Mx 2nd premolars

Most common primary:Mx lateral

Several genes may be involvedPAX9 gene produces DNA

binding protein that controls other genes in tooth development and was mutated in one family with hypodontia

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Hypodontia-7 yo female

When reviewing a radiograph, count the teeth

31

Panograph of 10 year old male with history of premature birth and delayed

development

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Ankylosed teethDescription: Fusion of

cementum and alveolar boneImproper terms:

submerged toothinfraocclusion

Use “ankylosed” insteadCause: unknownPossible causes: 1.familial pattern, probably

non-sex linked trait 2. no permanent successor

researchers disagree if ankylosis is associated/not

3. intermittent resorption and repair (increased repair)

Ankylosed teeth are often below occlusal tableMcDonald 186 9-12

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Ankylosed teethOther possible causes

Inadequate Arch spacePre-eruptive proximity of permanent molarsEctopic eruption of permanent molarsCaries

Occurrence: usually after root resorption beginsor after trauma (anterior teeth)

Highest Incidence- Md primary molars Diagnosing:

Tooth appears depressedTapping - solid sound (normal teeth have a cushioned sound)Tooth not mobilePDL on radiograph is discontinuous

McDonald 186 9-12

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Ankylosed tooth with permanent successor

Treatment:

Watchful waiting for normal exfoliation or

Extraction and placement of any needed space maintainers

35

Ankylosed tooth with no permanent successorIf there is adequate crown exposure

and sufficient root length, no successor and ankylosis occurs late:Keep as a functional unit

Restore proximal and occlusal contacts

Restore with SSC, composite resin, crown, gold casting crown, etc.

Assess perio periodically on adjacent teeth

If ankylosed tooth is extracted:Orthodontic referral/therapy or

Prepare for prosthodontics with space maintainance

36

All the primary molars are ankylosed

Permanent molars are tipping mesially

It is time to extract and provide space maintenance

37

Ankylosed permanent teeth

The incomplete eruption of a permanent molar may be related to a small area of root ankylosis

TX:

Remove soft tissue and bone covering the occlusal of the tooth for a path for eruption

If unsuccessful:

Surgical consult to luxate and break the ankylosis

A delay in treatment may result in permanent ankylosis

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Ectodermal Dysplasias-100 typesPresentation: Ectodermally derived

structures are altered:Anodontia or hypodontia of primary/permanent teethRetained primary teethHair-hypotrichosis absent/lanugo (fine) Sweat glands-hypohydrosis deficient

uncomfortable in warm weatherXerostomiaFissuring at corners of mouthSkeletal structures—normal with normal jaw development

Types:1. XLHED-X-linked recessive hypohidrotic

ectodermal dysplasia also called anhidrotic ectodermal dysplasia and Christ-Siemens-Touraine syndrome

2. Autosomal recessive ectodermal dysplasia

McDonald 133 7-39

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Ectodermal Dysplasias in children

Lack of teethPrimary anterior

teeth are conicalPrimary molars tend

to ankylosis without permanent successors

Difficult case to treat--overdentures McDonald 133 7-39

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Next week

Continuation of eruption considerations

McDonald 133 7-39

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Objectives

Define primate, leeway, secondary and closed spaces; agenesis, anodontia, hypodontia, oligodontia, and ankylosis.

List when the distal shoe is not indicated.

State when an RPD may be indicated to replace D, E, F, or G.

Identify sites with frequent ectopic/missing teeth.

Describe the consequences of ectopically positioned teeth

Describe the dx/tx for:Ectopic/impacted teethSuperrnumerariesAnkylosed teethAnterior diastemaAbnormal labial frenum

Explain why these terms are inaccurate“congenitally absent permanent teeth”“partial anodontia”“submerged teeth”“infra-occlusion”

Describe ectodermal dysplasia.