Space Maintainers

• Dr. Maan Al- Far

• M Dent SCi in Paediatric Dentistry

• University of Liverpool (England)

• Jordanian Dental Board

• Head of pediatric dentistry specialty

Definition

• Space maintainers are appliances used to maintain space or regain minor amounts of space lost,so as to guide the unerupted tooth into a proper position in the arch.

IDEAL REQUIREMENTS

It should maintain the entire mesio-distal space created by a lost tooth. It must restore the function as far as possible & prevent over-eruption of opposing teeth. It should be simple in construction. It should be strong enough to withstand the functional forces.

IDEAL REQUIREMENTS

It should not exert excessive stress on adjoining teeth. It must permit maintenance of oral hygiene.

IDEAL REQUIREMENTS

It must not restrict normal growth & development and natural adjustments which take place during the transition from deciduous to permanent dentition. It should not come in the way of other functions.

CLASSIFICATION OF SPACE MAINTAINERS

Removable or fixed .

With bands or without bands.

CLASSIFICATION OF SPACE MAINTAINERS

Functional or non-functional.

Active or passive.

Certain combinations of the above.

Fixed space maintainers- CLASS I (a) Non-functional types- i. Bar type. ii. Loop type. (b) Functional types- i. Pontic type. ii. Lingual arch type. CLASS II Cantilever type (distal shoe,band & loop.)

Removable space maintainers- Acrylic partial dentures

PLANNING FOR SPACE MAINTENANCE

Time elapsed since loss- . If space closure occurs, it usually takes place

during the first 6 months after the extraction.

When a primary tooth is removed & all factors indicate the need for space maintenance, it is best to insert an appliance as soon as possible after the extraction. Often the best approach, if possible, is to fabricate an appliance before the extraction & deliver it at the extraction appointment.

Dental age of the patient-

The chronologic age VS dental age

.Gron studied the emergence

of permanent teeth based on the

amount of root development,

as viewed on radiographs,at the time of emergence.she found that teeth erupt when three-fourths of the root is developed,regardless of the child’s chronologic age.

PLANNING FOR SPACE MAINTENANCE

PLANNING FOR SPACE MAINTENANCE

Amount of bone covering the unerupted tooth-

if there is bone covering the crowns, we

can predict that the eruption will not occur for

many months, a space-maintaining appliance is

indicated.

PLANNING FOR SPACE MAINTENANCE

d) Sequence of eruption of teeth-

Observing the relationship of developing &

erupting teeth adjacent to the space created by

the untimely loss of a tooth.

PLANNING FOR SPACE MAINTENANCE

Delayed eruption of the permanent tooth-

In case of impacted permanent tooth,it is necessary to extract the primary tooth,construct a space maintainer & allow the permanent tooth to erupt at its normal position.

If the permanent teeth in the same quadrant of the opposing dentition have erupted,it is advisable to incorporate an occlusal stop in the appliance to prevent overeruption in the opposing arch.

PLANNING FOR SPACE MAINTENANCE

Congenital absence of the permanent tooth-

If permanent teeth are congenitally absent, the dentist must decide whether it is wise to hold the space for many years until a fixed replacement can be provided or it is better to allow the space to close.

If the decision is made to allow the space to close, orthdontic treatment will be needed. referral to orthodontist

Presentation of problems to parents-

Take sufficient time to explain existing conditions

& discuss the possibility of the development of a future malocclusion if steps are not taken to maintain the space or to guide the development of the occlusion. Also explain that the space-maintaining appliance will not correct an existing malocclusion but will only prevent an undesirable condition from becoming worse or more complicated.

•

Fixed space maintainers

Band & loop space maintainer. Crown & loop appliance. Lingual arch. Palatal arch appliance. Transpalatal arch. Distal shoe. Esthetic anterior space maintainer.

Removable space maintainers

Acrylic partial dentures.

Full or complete dentures.

Removable distal shoe space maintainer.

Basic Space Maintainers

• Are PASSIVE

– .036 wire is very heavy and should not be

used to actively move teeth

Before Placing a Space

Maintainer

• Evaluate Arch Length

– Has the space already been lost?

– Is there excess space?

• Appropriate Radiographs

– Succedaneous tooth?

– Time to Eruption?

• Patient/Family Compliance

Space Maintainers are

Simple!

The 4 most basic pediatric space

maintainers

Basic Space Maintainers

• NANCE (Transpalatal Arch with Acrylic

Button Stop on Palate)

• LOWER LINGUAL HOLDING ARCH (LLHA)

• BAND/CROWN and LOOP

• DISTAL SHOE

Distal Shoe

• MAXILLARY or

MANDIBULAR

• Used when second

primary molar

requires extraction

and first permanent

molar has not erupted

Distal Shoe

• Should be evaluated with

radiograph prior to

cementation

– Length

– Position

• Will be replaced with

another space maintainer

when permanent teeth

erupt.

Distal Shoe

• Example of use in

partial eruption case.

Nance Appliance

• MAXILLARY ONLY

• Bands on first

permanent molars

Nance Appliance

• Cross Palatal Bracing prevents rotation and

around palatal root- this starts mesial

migration

• Acrylic Button provides additional stop

Transpalatal Holding Arch (TPA)

• Can be used like a

Nance.

• Advantage

– Lack of acrylic button

so less tissue irritation

and more cleansible

• Disadvantage

– Lack of anterior stop =

possible tooth shift (?)

Lower Lingual Holding Arch

• MANDIBULAR

ONLY

• Bands on first

permanent molars

• Anterior Stop =

Cinguli

Lower Lingual Holding Arch

• Mandibular incisors

often erupt lingually

and are pushed

forward by the tongue

• LLHA should not be

placed with primary

incisors

Extractions : LLHA Indicated?

• NO- note lingual

eruption

• Option: Reverse

Crown and Loops

**LLHA will be placed 2-

3 years later, prior to

loss . Simply cut off

loop and leave SSCs.

LLHA Omega Loops

• Omega Loops in area

of premolars allow

slight adjustment to fit

appliance

• Should not be used

to activate appliance

Appliance Activation Features

• Can be added by

attaching light wire

features

• This is beyond routine

space maintenance

Band/Crown and Loop

• MAXILLARY or

MANDIBULAR

• Unilateral most typical

• Can be bilateral if

permanent teeth are

not present

• Single tooth span

What About Removable

Appliances?

• Yes, they are possible, however………..

• High failure rate due to breakage and loss

• Parent and patient compliance must be exceptional

Which Space Maintainer?

• Distal Shoe = 2nd Primary Molar Extraction with

unerupted 1st Permanent Molar

• Nance or Band/Crown Loop = Maxillary

problem with 1st Permanent Molars present

• Lower Lingual Holding Arch = Mandibular

Problem with 1st Permanent Molars and

Permanent Incisors present

• Band/Crown and Loop= Primary 1st Molar

Extraction

Must I Plan to Replace a

Band/Crown and Loop ?

• All depends on ERUPTION SEQUENCE

– No, in maxillary arch

– Yes, in mandibular arch

– - may need LLHA later – Why? Canine should exfoliate

– prior to eruption of 1st premolar

– , making space maintainer defunct.

Space Maintainer Competency

• The following cases require space

maintainer consideration. Assume that

radiographs have been taken, there is no

abnormal pathology (other than dental

caries), and a successor is developing.

• Space analysis

Classification

• mixed dentition analysis

• Moyers

• Tanaka johonson

• Hixon and old father

• Ballard and wilie

Principles of space analysis

Non-radiographic space analysis

a. Moyer’s

b. Tanaka johnston

c. Ballard and wilie

. Radiographic analysis

a. Nance’s

b. Huckaba’s

Principles of space analysis

Combination of radiographs and prediction

charts

a. Hixon and old father

b. Staley kerber

Tanaka johnston analysis

Mandibular Arch Only: Chart

Dentition on the Odontogram

• Mandibular Arch Only : Chart

abnormalities and pathology (including

caries ) from the Panorex and Bite Wing

Radiographs

A Moyer’s space analysis predicted there

to be 2.3 mm of excess space in the

mandible.

Case no. 2

• child was referred by his general dentist

for ‘ tooth decay and crowding.’

Chart Maxillary Dentition Only on

the Odontogram

A Moyer’s space analysis predicts 1.2 mm

of space shortage in the maxilla

Treatment plan and sequence appointments

for the Maxillary Arch Only

Thank you

Discussion

Question 5

• Teeth #K and #S extracted. 5-6 y.o. child.

• Because permanent incisors are not erupted, LLHA not recommended. Options: Reverse band and loop #L-#19 and band and loop #T-#R.

“Cheyenne”

• Cheyenne presented for an initial visit at

the COD. She has had dental treatment on

and off throughout life. She is in no pain,

but mom reports that “we know she has

dental problems.”

Assuming normal dental development,

Cheyenne is 8 years old.

Cheyenne

• Mandibular Arch Only : Chart

abnormalities and pathology (including

caries ) from the Panorex and Bite Wing

Radiographs

Cheyenne

• Teeth Present:

19, K,L,M,23,24,25,26,R,S,T,30

Restorations: SSC #L

Pathology/Caries: #L and #S abscessed,

#28 severely ectopic.

Cheyenne

A Moyer’s space analysis predicted there

to be 2.3 mm of excess space in the

mandible.

Make a treatment plan and appointment

sequence for the mandibular arch only.

Cheyenne Tx Plan

• Extract #L,S and T and Place LLHA • #L and S due to abscess

• #T due to ectopic #28

– Appt #1: Fit bands and Impress for LLHA

Extract #L

– Appt. #2: Seat LLHA

Extract #S, T

Cheyenne

• Assuming normal dental development, at

what age will the space maintainer you

placed no longer be needed?

• Answer: When #21,28 and 29 erupt.

• Around age 12 years

“Justin” Case

• Justin was referred by his general dentist

for ‘ tooth decay and crowding.’

• The family does not believe they can

afford comprehensive orthodontic care ,

but does have dental insurance for

“routine dental care.”

Justin

A Moyer’s space analysis predicts 1.2 mm

of space shortage in the maxilla

Treatment plan and sequence appointments

for the Maxillary Arch Only

Justin

Please Evaluate This

Teaching Module

Thank You!

Question 4

• Lower Lingual Holding Arch (LLHA) #19-#30

Justin

• Teeth Present:

#3,A,B,C,7,8,9,10,H,12,J,14

• Restorations: #A-MO, #B-DO.

• Pathology/Caries: #3-M; #A-D; #B-M;

#H-D;#J-abscess, #14-MO

Note: #6 and #11 very advanced root

development.