This document presents information on tooth eruption. It discusses the phases of eruption as pre-eruptive, eruptive, and post-eruptive. It also outlines several theories of eruption, including root formation theory, bone remodeling theory, vascular pressure theory, and periodontal ligament traction theory. This last theory is considered one of the most acceptable as experimental evidence has shown that if the dental follicle is removed, no eruptive pathway forms, but if a silicon replica is substituted, eruption still occurs. The document concludes that while several theories attempt to explain tooth eruption, the full mechanism remains incomplete.

2. Presented by: Vaishnavi Jaiswal
BDS Ist Year
INSTITUE OF DENTAL SCIENCES BAREILLY

3.  Introduction to eruption
 Phases of eruption
 Theories of eruption
 Conclusion
 References
 Acknowledgement

4.  Eruption is the process by which the tooth move from
it’s developmental position to axial or occlusal position
or functional position within the jaw.
 Phases of tooth eruption:
 Phase 1: The Pre-eruptive phase
 Phase 2: The Eruptive phase
 Phase 3: The Post-eruptive phase

5.  Made by the deciduous and permanent tooth germs
within tissues of the jaw before they begin to erupt.

6.  Made by a tooth to move from it’s position within the
bone of jaw to its functional position in occlusion.
 This phase is sometimes divided into intraosseous and
extraocceous components.

7.  Maintaining the position of the erupted tooth in
occlusion while jaws continue to grow and compensate
for occlusal and proximal tooth wear.

8.  Although a debatable topic its been said as
multifractional process in which cause and results ate
difficult to separate.
 Numerous theories had been given but only few are
acceptable with valid and serious reasons.

9.  Root Formation Theory
 Bone Remodeling Theory
 Vascular Pressure Theory
 Periodontal Ligament Traction Theory

11. • This theory advocates existence of a ligament k/a Cushion-
Hammlock Ligament straddling the base of socket from
one bony wall to the other like a sling.
 The ligament provides a fixed base for growing root to react
against [produces a force to push the crown towards
occlusal surface].

12.  This is one of most acceptable theory.
 Major proof to this is:
1. If a tooth germ is removed experimentally while the dental follicle is
intact, an eruptive pathway is formed in overlying bone.
2. If silicon replica is also substituted for tooth germ, it also erupts.
 On the other hand if dental follicle is removed then no eruptive path
forms.

13.  Although it’s a contradicting theory because naturally
hydrostatic pressure doesn’t apply enough force for
eruption to take place.
 But experimentally by application of hypotensive drugs,
increases rate of eruption while stimulation of sympathetic
nerves, which causes vasoconstriction ; while decrease in
hydrostatic pressure decreases rate of eruption.

14.  Formation and renewal of PDL has been considered a
factor of tooth eruption because of traction power of
fibroblasts and experimental result using continuous
erupting rat incisors.

15.  Although each of these theories tried to explain the
mechanism of tooth eruption to some extent and some
is widely accepted but the answer to this question is
still incomplete.

16.  Orban’s Oral Histology and Embryology 14th edition;
GS Kumar (adaption editor), SN Bhaskar (US editor)
 Ten Cate’s Oral Histology 9th edition; Antonio Nanci
 Google search engine (image courtesy)

17.  I would like to show my gratitude towards our HOD of
Department of Oral Pathology and Microbiology Dr.
Madhusudhan Astekar sir for giving me this
opportunity to represent seminar on this topic.
 I would also like to thank our professors Dr. Gaurav
Sapra sir , Dr. Aashutosh Agrawal sir , Dr. Aditi Murari
ma’am and our PG Senior Dr. Shakir Alam boss who
helped me and guided me in proper understanding
about this topic.