SPACE SUPERVISION AND GROSS DISCREPANCY

Dir. HANA PERVEZ3RD year resident (FCPS)Department of orthodontics

SPACE RELATED PROBLEMS

In the mixed dentition stage, space related problems are of two types

• Lack of space causing the permanent teeth to erupt an abnormal position

• Interferences with eruption preventing a permanent tooth from erupting on a normal schedule and secondarily lead to space problems due to teeth drifting

Different scenarios in space related problems are

Excess space Premature tooth loss with adequate space Localized space loss (3mm or less) SPACE

regaining Mild to moderate crowding of incisors with

adequate space Moderate and severe generalized crowding

*EXCESS SPACE

Generalized spacing of permanent teeth

Maxillary midline diastema

Maxillary dental protusion and spacing

Missing permanent teeth

EXCESS SPACE

GENERALIZED SPACING OF PERMANENT TEETH• It could be due to small sized teeth in normal

sized arches or normal sized teeth in large arches• Infrequent finding in mixed dentition stage• Allow the eruption of all the permanent teeth

before closing space with fixed appliance

MAXILLARY MIDLINE DIASTEMA• Due to superior and distal positioning of

permanent canines in relation to lateral incisor roots forces central and lateral roots toward the midline while their crowns diverge distally

• This stage known as ugly duckling stage of development

• Corrects spontaneously as canines erupt

Ugly duckling phase of dental development

Treatment of diestema (2mm or less)• A maxillary removable appliance with finger spring

Treatment of diestema (greater than 2mm)

• Suspect any supernumerary tooth or intrabony lesion• 2x4 appliance therapyTreatment of dental protusion and spacing• In case where only tipping is required as in cases of

sucking habits HAWLEY APPLIANCE is indicated• Where bodily movements and rotation corrections

required fixed appliance therapy is indicated

MISSING PERMANENT TEETHMissing second premolars• Keep deciduous second molar as longsas possible to maintain

alveolar bone• If profile is somewhat protrusive extract deciduous at the age of 7

to 9 yrs • It allows first molar to drift into the space• Should be done when extractions are planned in opposing arches

Missing maxillary lateral incisors• Canine substitution for laterals • Prosthetic replacement of laterals

Auto transplantation• When two third root is formed, means in the mixed dentition stage• Commonly used to move premolars for incisors and or to replace

first molar with third molar

PREMATURE TOOTH LOSS WITH ADEQUATE SPACE

• Band and Loop space maintainerIndication:Unilateral or bilateral loss of a primary molar

Partial denture space maintainer

Indication • Missing anterior teeth• Greater than one tooth per segment

DISTAL SHOE SPACE MAINTAINER Indications • When E’s are lost prior to eruption of first permanent molar• Consists of guide plate along which 6 erupts• Guide plate must extend 1 mm below MMR ( mesial marginal ridge)

LINGUAL ARCH SPACE MAINTAINER

LOCALIZED SPACE LOSS (3mm or less) SPACE REGAINING

• Maxillary space regaining• Mandibular space regaining

Maxillary space regaining

A removable appliance with a fingerspring can be used to regain space by tipping a permanent first molar distally

A fixed appliance can also be used to distalize the molar with the help of open coil spring

Mandibular space regaining

For unilateral space regaining lingual arch and for bilateral lip bumper is indicated

MILD TO MODERATE CROWDING OF INCISORS WITH ADEQUATE SPACE

Irregular incisors, minimal space discrepency

3- 4 mm of anterior space is gained by disking the interproximal enamel surface of remaining primary incisors and canines

Space deficiency largely due to allowance for molar shift

Using leeway space by disking to increase arch length in conjunction with space maintainence

Moderate and severe generalized crowding

EARLY TREATMENT OF SEVERE CROWDING

• Maxillary dental or skeletal expansion, moving the teeth facially or opening the midpalatal suture

• Mandibular buccal segment expansion by facial movement of the teeth

• Advancement of incisors and distal movement of molars in either arch

Moderate arch length increase with multiple bonded and banded and a mechanism of expansion

In maxilla expansion achieved with the help of jackscrew appliance to open midpalatal suture

LATE MIXED DENTITION TREATMENT FOR SEVERE CROWDING

Options available to treat crowding in the late mixed dentition stage

• Distal molar movement• Extraoral appliance(headgears)• Serial extraction

DISTAL MOLAR MOVEMENT

Several approaches to distalize molars are Helical spring ( Pendulum appliance) Magnets TAD Steel and superelastic coil springs

Temporary anchorage device for molar distalization not indicated for patients younger than 12 years due to bone density and TAD instability

EXTRA ORAL APPLIANCE(HEADGEARS)

Force = 100g/sideDuration = 14 to 16 hrsRate of tooth movement =1 mm/month

EARLY SERIAL EXTRACTION

Indication:• Space discrepency is greater than 10mm• No skeletal discrepency of jaws• Normal overjet and overbite• Class 1 molar relation• Straight profile

A : Severe space deficiency and marked incisor crowdingB: Primary canines are extracted to align the incisors

C: Primary first molars are extracted when ½ to 2/3rd roots of premolar is formed to speed up its eruptionD: Extraction of first premolars after their eruption and canines erupt into the extraction space

ALTERNATIVE APPROACH

A : An alternative approachB : Begins with extraction of primary molar to speed up eruption of first premolar

C and D: When first premolars are erupted they are extracted and canines erupt into their space

ENUCLEATION: premature eruption of canine is a complication of serial extraction resulting in the impaction of first premolar when this happens surgically removal of premolar is done by a procedure known as enucleation

THANK YOU