FATHIMA SISINI

FINAL YEAR PART ONE

DEFINITION• Anchorage in orthodontics as

the nature and degree of resistance to displacement offered by an anatomic unit for the purpose of tooth movement. (GRABER)

• Anchorage is the site of delivary from which force is exerted(White and Gardnier)

CLASSIFICATION(MOYERS)

• ACCORDING TO MANNER OF FORCE APPLICATION

SIMPLE STATIONARY RECIPROCAL• ACCORDING TO JAWS INVOLVED

INTER MAXILLARY INTRA MAXILLARY• ACCORDING TO SITE

INTRA 0RAL EXRAORAL MUSCULAR

• INTRA ORAL;-TEETH,ALVEOLAR BONE,BASAL BONE

• EXTRA ORAL;-CERVICAL,OCCIPITAL,CRANIAL,FACIAL

• MUSCULAR

• According to number of anchorage units;-single or primary,compound,multiple or reinforced

CLASSIFICATION cntd….

INTRA ORAL ANCHORAGES

• 1) teeth

• 2)alveolar bone

• 3)basal bone

• 4)musculature

TEETH

• WHEN ONE TEETH MOVES THE OTHERS CAN ACT AS ANCHORAGE UNITS,IT DEPENDS ON

-ROOT FORM

-ROOT SIZE

-NO OF ROOTS

-ROOT LENGTH

-ROOT INCLINATION

ROOT FORM

• FLAT-RESIST MOVEMENTS IN MESIO-DISTAL DIRECTION,BUT LITTLE RESISTANCE BUCCOLINGUALLY

EG;-MANDIBULAR INCISORS AND MOLARS,BUCCAL ROOT OF MAXILLARY MOLARS

• ROUND:-RESIST HORIZONTALLY DIRECTED FORCE IN ANY DIRECTION

EG;-BICUSPID,PALATAL ROOT OF UPPER MOLARS

• TRIANGULAR;-MAXIMUM ANCHORAGEEG;-CUSPIDS,MAXILLARY CENTRALS AND LATERALS

SIZE AND NUMBER OF ROOTS

• MULTIROOTED TEETH HAVING THE MAXIMUM SIZE HAVE MAX. ANCHORAGE

ROOT LENGTH;-DIRECTLY PROPOTIONAL TO ANCHORAGE

AXIAL INCLINATION;-ANCHORAGE IS MORE WHEN FORCE EXERTED IS OPPOSITE TO THAT OF AXIS OF INCLINATION OF TEETH

ANKYLOSED TEETH;-NO PDL, SO NO MOVEMENT-EXCELLENT ANCHORAGE

ALVEOLAR BONE

• ALVEOLAR BONE RESIST TOOTH MOVEMENT UP TO ITS LIMIT,BEYOND THAT IT ALLOW TOOTH MOVEMENT BY REMODELLING

• HEALTHY ALVEOLAR BONE-MORE ANCHORAGE

BASAL BONE

• CERTAIN AREAS ACT AS RESISTANCE AREAS-PROVIDE GOOD ANCHORAGE-HARD PALATE,LINGUAL SURFACE OF MANDIBLE

MUSCULATURE

• HYPERTONIC LABIAL MUSCULATURE USED FOR ANCHORAGE IN LIP BUMPER

EXTRA ORAL

• 1)CRANIUM(OCCIPITAL OR PARIETAL ANCHORAGE:-ANCHORAGE OBTAINED FROM OCCPITAL OR PARIETAL BONE

EG:-HEAD GEAR TO RESTRICT MAXILLARY GROWTH• 2)CERVICAL:-ANCHORAGE FROM CERVICAL OR

NECK REGION• EG:-CERVICAL HEAD GEAR• 3)FACIAL BONES:-FACE MASK USED TO PROTRACT

MAXILLA TAKE ANCHORAGE FROM MANDIBULAR SYMPHYSIS

REVERSE HEAD GEARS TAKE ANCHORAGE FROM FOR HEAD AND CHIN

SIMPLE ANCHORAGE

• IS THE DENTAL ANCHORAGE SUCH THAT MANNER AND APPLICATION OF FORCE IS SUCH THAT IT TENDS TO CHANGE THE AXIAL INCLINATION OF THE TEETH

• THE RESISTANCE OF ANCHORAGE UNITS TO TIPPING IS USED TO MOVE OTHER TEETH

• THE COMBINED ROOT SURFACE AREA OF THE ANCHORAGE UNIT MUST BE DOUBLE TO THAT OF TEETH TO BE MOVED

• EG:-PALATALY PLACED PREMOLAR IS PUSHED IN TO THE ARCH BY REST OF THE TEETH AS ANCHOR UNITS

STATIONARY ANCHORAGE

• MANNER AND APPLICATION OF FORCE TEND TO DISPLACE THE ANCHORAGE UNIT

• RESISTANCE PROVIDED BY THE ANCHORAGE UNITS IS AGAINST BODILY MOVEMENTS(DISPLACEMENT)

RECIPROCAL ANCHORAGE

• RESISTANCE OFFERED BY TWO MALPOSED UNITS WHEN THE APPLICATION OF TWO EQUAL AND OPPOSITE FORCES TEND TO MOVE EACH UNIT TO A MORE NORMAL POSITION

• EG:-CLOSURE OF MIDLINE DIASTEMA CROSS BITE ELASTICS,EXPANSION

APPLIANCES

INTRA MAXILLARY ANCHORAGE

• TEETH ARE TO BE MOVED AND THE ANCHORAGE UNITS ARE IN THE SAME ARCH

INTER MAXILLARY ANCHORAGE

• TEETH ARE TO BE MOVED IN ONE ARCH AND RESISTRANCE UNITS ARE IN OPPOSITE ARCH

• EG:-CLASS II ,CLASS III ELASTICS

SINGLE OR PRIMARY ANCHORAGE

• SINGLE TEETH WITH MORE ALVEOLAR SUPPORT USED TO MOVE ONE WITH LESSER SUPPORT

COMPOUND ANCHORAGE

• ANCHORAGE PROVIDED BY MORE THAN ONE TEETH WITH GREAT SUPPORT TO MOVE TOOTH WITH LESS SUPPORT

REINFORCED ANCHORAGE

• MORE THAN ONE TYPE OF RESISTANCE UNIT IS UTILIZED

• EG:-A)TO AUGMENT THE INTRA ORAL ANCHORAGE, EXTRA ORAL ANCHORAGES TRANS PALATAL ARCH,AND LINGUAL ARCHES IS USED

B)UPPER ANTERIOR INCLINED PLANE USED FOR FORWARD MOVEMENT OF MANDIBLE USES MUSCULAR ANCHORAGES

MINI DENTAL IMPLANTS

• USED IN PATIENTS HAVING MULTIPLE LOST TEETH OR HYPODONTIA OR TO AUGMENT TEETH WITH PERIODONTAL DISEASES

• CLASSIFICATION-ACCORDING TO EXPOSURE OF HEAD:-

OPEN-HEAD IS EXPOSED TO ORAL CAVITY-USED WHEN SOFT TISSUES ARE NOT MOVABLE

CLOSED-EMBEDED UNDER SOFT TISSUES-MOVABLE TISSUES

• ACCORDING TO IMPLANT PLACEMENT1)SELF TAPPING METHOD:-IMPLANT TAPPED

IN TO A PREVIOUSLY DRILLED HOLE-SMALLER DIAMETER IMPLANTS

2)SELF DRILLING METHOD:-IMPLANT IS ITSELF DRILLED IN TO THE BONE-LARGER DIAMETER IMPLANT

• ACCORDING TO THE PATH OF INSERTION:-1)OBLIQUE;-30=60DEGREES TO LONG AXIS OF

TEETH-WHERE INTER RADICULAR BONE IS NARROW

2)PERPENDICULAR;-INSERTED PERPENDICULAR TO THE BONE SURFACE-WHEN SUFFICIENT INTER RADICULAR BONE PRESENT

SITE OF PLACEMENT OF MICRO IMPLANTS

• 1)MAXILLARY TUBEROCITY

• 2)INFRA ZYGOMATIC CREST

• 3)BUCALLY B/W MAX 6 & 7

• 4)BUCALLY B/W MAX 5&6

• 1)MAXILLRY POSTERIORS

• 2)RETRACTION OF MAX.ANTERIORS &INTRUSION OF MAX.POSTERIORS

• 3)SAME AS ABOVE

• 4)SAME AS ABOVE &TO TIP BUCALLY

• 5)BUCALLY B/W MAX 3&4

• 6)LABIALLY B/W MAX. CENTRALS

• 7)PALATALLY B/W MAX 5&6

• 5)DISTAL &MESIAL MVMT OF MAX.MOLARS AND INTRUSION OF MAX BUCCAL TEETH

• 6)INTRUSION AND TORQUE CONTROL OF INCISORS

• 7)RETRACTION OF MAX ANTERIORS AND INTRUSION OF MAX MOLARS

• 1)RETROMOLAR PADS

• 2)BUCALLY B/W MAND. 6&7

• 3)BUCALLY B/W 4&5• 4)BUCALLY B/W 3&4• 5)MADIBULAR

SYMPHYSIS

• 1)UPRIGHTING&RETRACTION OF MAND.TEETH

• 2)INTRUSION &DISTAL MVMT OF MAND MOLARS,RETRACTION OF MAND.ANTERIORS

• 3)SAME AS ABOVE• 4)PROTRACTION OF

MOLARS• 5)INTRUSION OF

MANDIBULAR ANTERIORS

SITES IN MANDIBLE

ANCHORAGE PLANNING• FACTORS AFFECTING ARE:-1)NO; OF TEETH BEING MOVED:-TO MOVE GREATER

NO;OF TEETH, ANCHORAGE SHOULD BE MORE2)TYPE OF TEETH:-TEETH HAVING MORE SURFACE

AREA REQUIRE MORE ANCHORAGE3)TYPE OF MOVEMENT:-BODILY MOVEMENT REQUIRE

MORE ANCHORAGE4)DURATION:-PROLONGED TREATMENTS REQUIRE

GOOD ANCHORAGE5)SKELETAL GROWTH PATTERN:- A)VERTICAL-REQUIRE MORE ANCHORAGE DUE TO

POOR TONICITY OF FACIAL MUSCLES B)HORIZONTAL-VICE VERSA

• 6)OCCLUSAL INTERLOCK:-GOOD OCCLUSION=GOOD ANCHORAGE

• ANCHORAGE LOSS:-UNWANTED TOOTH MOVEMENTS DURING ORTHODONTIC THERAPY

• BASED ON THE ANCHORAGE LOSS THE ANCHORAGE DEMAND OF THE EXTRACTION CASES ARE OF THREE TYPES

• MAXIMUM,MODERATE,MINIMUM

MAXIMUM ANCHORAGE CASES

• ANCHORAGE DEMAND IS VERY HIGH

• NOT MORE THAN 1/4TH OF THE EXTRACTION PLACE SHOULD BE LOST BY ANCHORAGE LOSS

• SO AUGMENTATION OF ANCHOR TEETH REQUIRED

MODERATE ANCHORAGE CASES

• ANCHORAGE LOSS 1/2TH TO 1/4TH OF EXTRACTION SPACE

MINIMUM ANCHORAGE CASES

• ANCHORAGE LOSS CAN BE MORE THAN 1/2TH OF EXTRACTION SPACE

BIBLIOGRAPHY

• TEXT BOOK OF ORTHODONTICS-S I BHALAJI,PROFET

• WWW.FUNNYTOOTH.COM

• WWW.WIKIPEDIA.COM