Development of

OcclusionFrom Birth upto Primary Dentition

Roshalmaria ThomasIV/I roll no-75

DEFINITION (derived from the latin word occluso) OCCLUSION IS DEFINED AS RELATIONSHIP

BETWEEN ALL THE COMPONENTS OF MASTICATOR SYSTEM IN NORMAL FUNCTION, DYSFUNCTION AND PARAFUNCTION

THE VARIOUS STAGES OF OCCLUSAL DEVELOPMENT

1. PREDENTATE JAW RELATIONSHIP2. DECIDUOUS DENTITION PERIOD3. MIXED DENTITION PERIOD4. PERMANENT DENTITION PERIOD

THE PREDENTATE PERIOD

6 MONTHS AFTER BIRTHGUM PADS- ALVEOLAR PROCESS AT

TIME OF BIRTHDENTAL GROOVETRANSVERSE GROOVESGINGIVAL GROOVELATERAL SULCUSCOMPLETE OVERJETINFANTILE OPEN BITE

• NATAL TEETH- TEETH FOUND TO HAVE ERUPTED AT THE TIME OF BIRTH

• NEONATAL TEETH- ERUPT DURING FIRST MONTH OF LIFE

DECIDUOUS DENTITION PERIODERUPTION OF ALL PRIMRY TEETH

IS COMPLETED BY 2.5-3.5 YRS OF AGE

SEQUENCE OF ERUPTION- A-B-D-C-E

BETWEEN 3-6 YRS THE DENTITION IS RELATIVELY STABLE

6 mos

7 mos

7.5 mos

9 mos

12 mos

14 mos

16 mos

18 mos

20 mos

24 mos

Status of Dentition

SOME OF THE CHARACERISTIC CLINICAL FEATURES OF DECIDUOUS DENTITION ARE1. BOTH THE DENTAL ARCHES ARE HALF

ROUND OR OVOID IN SHAPE2. ALMOST NO CURVE OF SPEE IS PRESENT3. SHALLOW CUSPID INTERDIGITATION4. SLIGHT OVERJET5. DEEP BITE6. VERTICAL INCLINATION OF INCISORS7. SPACED DENTITION8. DIFFERENT MAXILLOMANDIBULAR

RELATIONS1. FLUSH TERMINAL PLANES2. MESIAL STEP TERMINAL PLANES3. DISTAL STEP TERMINAL PLANES

SPACING

• DELABARRE(1918) WAS FRIST TO DESCRIBE INTERDENTAL SPACING SPACING IN PRIMARY DENTITION

• BAUME-1950-

DENTITION

SPACED

PRIMATE SPACES

PHYSIOLOGIC SPACES

NON-SPACED

ANTERIOR TEETH RELATIONSHIPOVERBITEEDGE TO EDGE BITEOVERJET

CANINE RELATIONSHIP

CLASS I CLASS II CLASS III

ARCH DIMENSIONSo ZIGMONDY 1890o FRANK & BAUME- CHANGES THAT

TAKE PLACE IN ARCH BY LOSS OF PRIMARY TEETH AND DEVELOPMENT OF OCCLUSION

ARCH SIZEARCH LENGTHARCH CIRCUMFERENCEARCH WIDTH

BIBLIOGRAPHY• TEXTBOOK OF ORTHODONTICS-

BHALAJI• TEXTBOOK OF PEDIATRIC

DENTISTRY- NIKHIL MARWAH