The document discusses the biological considerations related to maxillary impressions in prosthodontics, covering topics such as microscopic anatomy, the anatomy of limiting structures, and tissue changes in complete denture wearers. Key areas include the anatomy of the maxillary edentulous arch, stress-bearing areas, and the behavior of oral mucosa under stress. It concludes that understanding dental anatomy is critical for effective denture fabrication and tissue preservation.

1. 1
PRESENTED BY MODERATOR
MAJ MUNSHI KAMRUL HASAN MAJ RANDHIR SINGH
JR-1(PROSTHODONTICS)
BIOLOGICAL CONSIDERATIONS
OF MAXILLARY IMPRESSIONS

2. 2
CONTENTS
• Introduction
• Microscopic Anatomy
• Anatomy of limiting structures.
• Behavior of the mucosa under stress.
• Tissue changes in complete denture wearers.
• Summary
• References.

3. 3
INTRODUCTION

4. 4
MICROSCOPIC ANATOMY
CREST OF RESIDUAL RIDGE

5. 5
MICROSCOPIC ANATOMY
SLOPE OF RIDGE:
Loosely attached mucous membrane.
Epithelium - non keratinized.
Submucosa – has loose connective tissue so cannot
withstand the forces of mastication as well as crest of
the ridge.

6. 6
MICROSCOPIC ANATOMY
ANTEROLATERAL AND POSTEROLATERAL PART OF THE HARD PALATE

7. 7
MAXILLARY EDENTULOUS ARCH

8. MAXILLARY EDENTULOUS ARCH
LIMITING STRUCTURES SUPPORTING STRUCTURES
STRESS BEARING AREAS RELIEF AREAS
PRIMARY SECONDARY
1. Labial Frenum
2. Labial Vestibule
3. Buccal Frenum
4. Buccal Vestibule
5. Hamular Notch
6. Posterior Palatal
Seal Area 1. Hard Palate on
either side of Palatal
Raphe
2. Maxillary tuberosity
1. Rugae
2. Alveolar ridge
1. Incisive
Papilla
2. Cuspid
Eminence
3. Mid-Palatine
Raphe
4. Fovea
Palatina

9. 9
LIMITING STRUCTURES
1. Labial Frenum
2. Labial Vestibule
3. Buccal Frenum
4. Buccal Vestibule
5. Hamular Notch
6. Posterior Palatal Seal Area

10. Its a fold of mucous membrane at the median line.
LABIAL FRENUM

11. The labial vestibule extends from buccal frenum on one side to
buccal frenum on other side and is divided into a left and right labial
vestibule by the labial frenum.
LABIAL VESTIBULE

12. • Its a fold of mucous membrane
• Separates labial and buccal vestibule.
BUCCAL FRENUM

13. It can be single fold, double, broad or fan shaped.
BUCCAL FRENUM
1. The levator anguli oris
(caninus) muscle
2. The buccinator
3. Orbicularis oris
MUSCLE ATTACHMENT

14. The portion of oral cavity that is bounded on one side by the teeth,
gingiva and alveolar ridge (residual alveolar ridge) on the lateral side
by the cheek posterior to the buccal frenum”
BUCCAL VESTIBULE

15. Size variation
• Contraction of the buccinator muscle
• Position of the mandible
• Amount of bone loss
BUCCAL VESTIBULE

16. Depression that lies between maxillary tuberosity & hamular
process of the medial pterygoid plate.
HAMULAR NOTCH

17. POSTERIOR PALATAL SEAL AREA

18. Effect of type of soft palate on posterior palatal seal area
POSTERIOR PALATAL SEAL AREA

19. SUPPORTING STRUCTURES
1. Hard Palate on
either side of Palatal Raphe
2. Residual Alveolar Ridge
1. Rugae
2. Maxillary tuberosity
PRIMARY STRESS BEARING
AREA
SECONDARY STRESS BEARING
AREA

20. 20
HARD PALATE
The hard palate is formed by palatine process of maxillary bone &
horizontal plate of palatine bones.

21. 21
• Epithelium is well keratinized stratified squamous epithelium.
• Anterolateral Area:Fatty zone
• Posterolateral Area: Glandular zone.
• Mid Palatine Raphe: Submucosa is extremely thin and
non resilient.
HARD PALATE

22. • It is a bulbuos extension of residual ridge in second and third molar
region
MAXILLARY TUBEROSITY

23. 23
The portion of the alveolar ridge and its soft tissue covering which
remains following the removal of teeth.
RESIDUAL RIDGE

24. 24
• Raised area of dense connective tissue in ant 1/3 of palate
• Mucosa is keratinized and the submucosa is fibrous and contains fatty
tissue
RUGAE

25. RELIEF AREAS
1. Incisive Papilla
2. Cuspid Eminence
3. Mid-Palatine Raphe
4. Fovea Palatina

26. It is a midline structure situated behind the central incisor.,
overlies incisive foramen , which is the exit point for nasopalatine
nerves and vessels.
INCISIVE PAPILLA

27. • Visible pits near the midline of the palate in posterior region ,
formed by coalescence of the ducts of several mucous glands
FOVEA PALATINA

28. · Bony elevation on residual ridge after extraction of canine.
CUSPID EMINENCE

29. BEHAVIOUR
OF
ORAL MUCOSA UNDER STRESS
• Mean denture bearing area
Maxilla -22.96cm2
Mandible-12.25cm2
• Area of periodontal ligament -45cm2

30. • Masticatory loads during chewing
For natural teeth- 44lbs(20 kg)
For artificial teeth- 13-16lbs(6-8 kgs)
• With complete dentures , the mucous membrane is forced to serve
the same purpose as the periodontal ligament that provide for the
natural teeth.
BEHAVIOUR
OF
ORAL MUCOSA UNDER STRESS

31. SOFT TISSUE
AND
HARD TISSUE CHANGES
• Tolerance of the person to injury differs from individual to
individual.
Denture wearer
Tolerance of mucosal tissues
If less If more
Injury & inflammation. Fibrous growth
Flabby hyperplastic
tissue

32. HARD TISSUE CHANGES
RESIDUAL RIDGE RESORPTION

33. CONCLUSION
• The scientific knowledge of denture supporting and influencing
struture forms an integral part of denture fabrication.
• The macroscopic anotomy helps in the meticulous replacement of
missing strutures.
• The microscopic level enhances the preservation of what remains.
thus the health of the tissues can be preserved.

34. REFERENCES
1. Zarb. Bolender:Prosthodontic Treatment for Edentulous
patients.13th
edn.the c.v.mossby co.,2004.
2. Charles M. Heartwell: Textbook of complete dentures. 5th
edition
3. Sheldon Winkler. Essentials of complete denture prosthodontics.
2nd
edition
4. Orbans:oral histology and embryology
5. Kapur,k:Effect of complete dentures on alveolar mucosa.
J.prosthet dent13:1030-1037,1963
6. Judson.C.Hickey, Charles.l.Bolender.:Bouchers Prosthodontic
Treatment for Edentulous Patients.9th
edn.The c. v. Mossy
Co,1985
7. Tencate:oral histology, development struture and function