The document discusses factors related to physiologic tooth form that protect the periodontium. It identifies direct factors like proximal contact relations and embrasures, and indirect factors such as crown form, root form, angulation of teeth, self-cleansing ability, occlusal anatomy, continuity of marginal ridges, facial line angles, and continuity of central grooves on posterior teeth. Physiologic tooth form with these characteristics helps maintain the periodontium by facilitating proper distribution of forces, food flow, and cleansing of the teeth and gums.

1. Menatalla M. Elhindawy

2. Physiologic tooth form
protecting
Periodontium

3. Periodontium
 Is the attachment system
 Tissues supporting the tooth into its
socket

4. Physiologic tooth form protecting Periodontium
Direct factors
I. Proximal contact relation.
II. Interproximal spaces.
III. Embrasures or spill ways.
IV. Facial and lingual contours
of the crown.
V. Curvature of cervical line.
Indirect factors
I. Crown form
II. Roof form
III. Angulation of crown and root
IV. The self-cleansing ability of the tooth.
V. Occlusal anatomy.
VI. Continuity of marginal ridges.
VII. Continuity of central grooves of post.
Teeth.
VIII. Facial line angles.

5. Physiologic tooth form protecting Periodontium
Indirect factors
I. Crown from
Proximal contact area

6. Physiologic tooth form protecting Periodontium
Indirect factors
I. Crown from
Proximal contact area
Facial & lingual contour

7. Physiologic tooth form protecting Periodontium
Indirect factors
I. Crown from
Proximal contact area
Facial & lingual contour
Geometric outline of the crown

8. Physiologic tooth form protecting Periodontium
Indirect factors
II. Root from
 Single
 Multi-rooted.
 Facial…. Cone shaped
 Proximal …. Broad

9.  Lingual angulation of the
Physiologic tooth form protecting Periodontium
Indirect factors
III. Angulation of the root & crown
of Mand. Post. teethCROWN

10.  Lingual angulation of the
Physiologic tooth form protecting Periodontium
Indirect factors
III. Angulation of the root & crown
of Mand. Post. teethCROWN
Physiologic occlusion Normal distribution of masticatory forces

11. Physiologic tooth form protecting Periodontium
Indirect factors
III. Angulation of the root & crown
 Distal angulation of the of permanent molars
CROWN
&
ROOT
Mesial drift of teeth
Maintenance of the proximal contact area

12. Physiologic tooth form protecting Periodontium
Indirect factors
IV. Self cleansing ability
 Proper form of the teeth with smooth
rounded surfaces.
 Proper alignment of the teeth in the
dental arches.
 Normal gingival attachments
 Brushing activity of the tongue, lips
and cheeks.
 The washing effect of the saliva and
fluid intake.
 The friction of the food material during
mastication and the usual home care
of the teeth.

13. Physiologic tooth form protecting Periodontium
Indirect factors
V. Occlusal anatomy

14. Physiologic tooth form protecting Periodontium
Indirect factors
VI. Continuity of the marginal ridges
The height of the marginal ridges of adjacent
teeth is at the same level.
 Shape of marginal ridges of the adjacent teeth
from occlusal or lingual embrasure.
Proper embrasure form.

15. The two facial line angles of the anterior teeth
and premolars of both arches are normally
quite prominent, when compared to the
rounded lingual line angles of the same teeth.
They are normally located directly adjacent to
each other
Physiologic tooth form protecting Periodontium
Direct factors
VII. Facial line angles
Symmetry in embrasure

16. The central developmental grooves of
posterior teeth are normally aligned into
one continuous valley.
This allows for a trough antero-posteriorly
through the centers of the occlusal surfaces
of the posterior teeth.
Physiologic tooth form protecting Periodontium
Indirect factors
VIII. Continuity of the central groove of posterior teeth
More efficient food flow pattern during
mastication.

17. Any questions??

18. Thank you..