SALIVA and its role in prosthodontics..pptx

its an important topic in MDS prosthodontics basic sciences exam

1. Saliva And It’s Role In Prosthodontics Sourabh Gandhi 1 st MDS Date-3/12/2024

2. Contents Introduction Definition Classification of salivary glands Development of salivary glands Mechanism of secretion Composition of saliva Properties of saliva Factors affecting flow of saliva Clinical considerations Prosthodontic considerations Take home points references

3. INTRODUCTION WHAT IS SALIVA? WHY IS IT IMPORTANT?

4. Definition “Saliva is a clean, tasteless, odorless slightly acidic viscous fluid, consisting of secretions from the parotid ,sublingual , submandibular glands and the mucous glands of oral cavity” A.K.Jain’s Human physiology,5 th edition “Saliva is a complex fluid produced by salivary glands,the most important function of which is to maintain the well being of oral cavity.” Tencates book of oral histology

5. Classification of salivary glands Major salivary glands Parotid gland Submandibular gland Sublingual gland Minor salivary glands Labial/buccal Palatine Lingual Glossopalatine Von ebner’s glands

6. Classification based on salivary secretion Serous Parotid Von ebner’s Mucous Labial Palatine Glossopalatine Post.tongue Mixed submandibular Sublingual Anterior tongue

7. Gray’s anatomy 41 st edition

8. Parotid gland -The parotid is the largest of the salivary glands its superficial portion is palpable as it overlies the ramus of the mandible. Shape-resembles an inverted three sided pyramid Weight- 20 to 30 gms Secretory duct- Stenson’s duct located opposite upper second molar

9. Blood Supply External carotid artery and its branches that arise within the gland. The veins drain into the external jugular vein and internal jugular vein. Nerve supply Parasympathetic - auriculotemporal nerve Sympathetic - derived from theplexus around the middle meningeal artery Parotid fascia -greater auricular nerve Lymphatic drainage- first to the parotid nodes and from there to the upper deep cervical nodes

10. Submandibular gland The submandibular gland is the second largest salivary gland. Duct Whartons duct – opens on the floor of the mouth, on the summit of the sublingual papilla , at the side of the frenulum of the tongue.

11. Blood supply It is supplied by the facial artery. Nerve supply It is supplied by branches from the submandibular ganglion. Lymphatic drainage The veins drain into the common facial or lingual vein. Lymph passes to submandibular lymph nodes.

12. Sublingual gland This is smallest of the three salivary glands. It is almond shaped and weighs about 3 to 4g About 15 ducts emerge from the gland. Most of them open directly into the floor of the mouth on the summit of the sublingual fold. The gland receives its blood supply from the lingual and submental arteries. The nerve supply is similar to that of the submandibular gland

13. Minor salivary glands situated beneath the mucosa of the oral cavity, palate, paranasal sinuses, pharynx, larynx, trachea, and bronchi. They are most numerous in the buccal, labial, palatal, and lingual regions. The minor salivary glands have the same basic structure as the major salivary glands but are either entirely mucous glands, on the hard palate, or mixed seromucous glands, as in the sinonasal and oral cavities. It has been estimated that there are more than 750 minor salivary glands.

14. Development of salivary glands Embryology, Physiology, and Biochemistry of the Salivary Glands KENNETH R. NISSIM, ROBERT L. WITT AND JONATHAN A. SHIP

15. Mechanism of secretion salivary glands are controlled mainly by parasympathetic nervous signals all the way from the superior and inferior salivatory nuclei in the brain stem. Salivation can also be stimulated or inhibited by nervous signals arriving in the salivatory nuclei from higher centers of the central nervous system. Salivation also occurs in response to reflexes originating in the stomach and upper small intestines—particularly when irritating foods are swallowed or when a person is nauseated because of some gastrointestinal abnormality. Guyton and hall textbook of medical physiology 13 th edition

16.   The   acinar cells   secrete the initial saliva, which is  isotonic .   The   ductal cells   modify the initial saliva. There is net absorption of solute because more NaCl is absorbed than KHCO3 is secreted. Because ductal cells are water impermeable, water is not absorbed along with the solute, making the final saliva   hypotonic. whole saliva secretion varies between 800- 1500 ml / day or 1.0 to 3.0 ml / minute with a pH in the range of 6-7 for unstimulated whole saliva.

17. PROPERTIES OF SALIVA V olume - 1000-1500ml of saliva is secreted per day & approx. 1ml/minute.  R eaction - mixed saliva from all the glands is slightly acidic with pH of 6.36-6.85  S pecific gravity - ranges between 1.002-1.012 .  O smolality - saliva is hypotonic to plasma.  C onsistency - slightly cloudy and viscous

18. Composition

19. Role of saliva in prosthodontics

20. Pre-treatment evaluation Major salivary glands orifices should be examined to ensure they are open. The amount and consistency of saliva affects denture retention and construction. Amount of saliva can be classified as: • Class I: Normal • Class II: Excessive • Class III: Xerostomia

21. methods for collection of whole saliva 1)Draining Method 2)Spitting method 3)Suction method 4)Swabbing method International Journal of Oral Health Dentistry; July-September 2017;3(3):149-148

22. Role of saliva in making impressions Excessive amount of saliva: pits and void  Thick and ropy (mucinous) type : poor tissue details  If rough texture of palatal mucosa viscosity of saliva is the matter of concern.  Excessive salivation particularly by Maxillary and Sublingual glands presents a problem in impression making.

23. When this problem exists Atropine sulfate can be administered orally prior to impression making. The new dentures may feel like foreign bodies and stimulate the flow of saliva. The patient should be assured that the feeling and flow of saliva will decrease gradually. Premedication with antisialogogues

24. Excessive secretions of mucous from the Palatal glands may distort the impression material in the posterior two thirds of the palate. To counteract this problem- The palate may be massaged to encourage the glands to empty. The mouth may be irrigated with an astringent mouthwash just prior to inserting impression material. The palate may be wiped with gauge .

25. Failure to counteract the thick and ropy saliva because of heavy secretions of mucous from palatal glands under maxillary denture will result in: Dislodgement of the denture. Presence of voids in the impression surface while the impression material sets. Forms a factor in causing the patient to gag while impressions are made and after placement of new dentures.

26. Cleaning the Alginate Impression Most patients have thin, serous saliva. This type of saliva can be removed by briefly holding the impression under a gentle stream of cool tap water. some patients have thick, ropy saliva that is difficult to remove. Therefore it is recommended that a thin layer of dental stone be sprinkled on the surface of the impression. The stone adheres to the saliva and acts as a disclosing agent. When the impression is placed under running tap water, the saliva can be removed by light brushing with a wet camel hair brush

27. Control of Saliva during Impression for Removable Partial Denture Using Irreversible Hydrocolloid Rinsing the mouth with- Astringent Mouthwash Packing the mouth with- 4x4 inch gauze to form absorptive strip Tandem Impression Technique Use of an Antisialagogue Agents ( 15mg propantheline bromide tablet taken 30 minutes before the impression appointment may be indicated in certain instances)

28. Role Of Saliva in Denture Saliva is a major factor in evaluating the physical influences that contribute to the denture retention

29. How saliva helps in complete denture retention Adhesion Adhesion is defined as the physical attraction of unlike molecules to one another. • It depends on: Close adaptation of denture. Size of denture-bearing area. Type of saliva. • Adhesion also takes place directly between the denture base and mucosa in case of xerostomia (lack of saliva), but this leads to ulcerations and abrasions in the mucosa Saliva in Prosthodontic Therapy – All You Need To Know!

30. Cohesion • Cohesion is defined as the physical attraction of like molecules to one another. • This occurs within the film of saliva and aids in retention • Normal saliva is not very cohesive; hence, retention from mucosa interface is more dependent on adhesion and surface tension. • As viscosity of saliva increases, greater is the cohesion but very thick, mucous saliva can physically push the denture out, resulting in loss of retention

31. Interfacial surface tension • Interfacial surface tension is defined as the tension or resistance to separation possessed by a film of liquid between two well adapted parallel surfaces. • Interfacial surface tension is also dependent on existence of a liquid/air interface at the boundary of the liquid/solid contact The external boundary of the mandibular denture is always filled (immersed) in saliva, thereby reducing the surface tension effect Hence, interfacial surface tension plays a significant role in retention of only the maxillary denture

32. Capillarity That quality or state, which because of surface tension causes elevation or depression of the surface of a liquid that is in contact with a solid. • Capillarity causes the thin film of saliva to rise and increase its contact with the denture base and the mucosa. • Close adaptation of the denture base to mucosa is important for capillarity to provide effective retention.

33. Denture Insertion and After Phase New dentures are often interpreted as foreign objects by the oral system. This leads to stimulation of salivary glands to produce saliva. On excessive salivation patient may complain of floating dentures. But this decreases over the weeks after denture insertion .

34. XEROSTOMIA (HYPOSALIVATION) When the unstimulated whole saliva flow rate is less than 0.1 mL per minute (normal values, 0.3– 0.4  mL per minute) and stimulated saliva flow rate is less than 0.5–0.7 mL (normal values, 1–2 mL per minute), it can be defined as hyposalivation. Temporary –fear ,anxiety ,fever , dehydration Permenant- Sialolithiasis ,aplasia /hypoplasia of salivary gland ,bell’s palsy,age, RADIATION ,etc.

35. Xerostomia and salivary gland hypofunction are almost inevitably seen in patients whose salivary glands are irradiated for head and neck cancer. Sensation of oral dryness occurs early in the course of radiation. It has been shown that 24 hrs after administration of only 2.25 Gy(225Rads) there is already a 50% decrease in flow of the parotid saliva. When exposure exceeds 50Gy (5000Rads) the reduction in flow is profound &for the most part permanent , the decrease amounts to >90%. Parotid glands are the most sensitive to ionising radiation the other glands in the decreasing order of sensitivity- submandibular, sublingual and the minor glands

36. Biological aging Systemic diseases: Rheumatoid diseases (Sjogren’s syndrome), immune system damage (AIDS), hormonal disorders (diabetes mellitus), and neurological disorders (Parkinson’s disease) Decrease in the chewing efficiency Inflammation in the salivary glands, surgical removal of salivary glands Side effects of drugs like anti arrythmics,antipsychotics Radiotherapy (ionized radiation Caffeine and alcohol consumption. Depression 1.Burning sensation on the tongue 2. Difficulty in eating, especially dry food 3. Difficulty in swallowing, chewing, or speaking 4. Frequently feeling thirsty 5. Difficulty in using dentures 6. Dryness and cracks in the lips 7. Halitosis 8. Fissured tongue with atrophy of the filiform papillae and a lobulated, erythematous appearance of the tongue 9. Increased risk of salivary gland stones 10. Mouth soreness and oral mucositis 11. Dysgeusia—altered taste sensation CAUSES SYMPTOMS

37. Symptoms

38. Management 1. Drinking liquids frequently, even during the night. 2. Sugar-free chewing gums may increase salivary flow. 3. Smoking, alcohol, and sugar intake must be avoided. 4. Saliva substitutes and saliva stimulants (methylcellulose ) could be used in severe cases. 5. Bacterial plaque should be controlled. 6. Tooth pastes, gels, and mouth rinses with fluoride should be used. 7. Vitamin C intake can be increased. 8. Oral health products containing alcohol and sodium lauryl sulfate should not be used Medication – capable of stimulating salivary glands- pilocarpine 5 – 10 mg, 3/4 times daily, administered 30 minutes before food

39. ARTIFICIAL SALIVA SUBSTITUTES - Commercially available products contain Carboxyl methylcellulose -lubrication. Animal mucins -to increase viscosity. Parabens- inhibit bacterial growth Sugar free agents- xylitol, sorbitol- sweeteners, mineral salts-simulate electrolyte content. Fluoride - Remineralization.

40. Impressions In patients with xerostomia - A very careful gentle approach is essential for patients with dry mouth as the mucosa and lips are easily traumatized. - The lips should be coated with petroleum jelly to help with retraction and access to the oral cavity. - The operator’s gloved fingers should be wetted to prevent them from sticking to the soft tissues. - A mirror should be used to facilitate insertion of the tray as it is less bulky than the fingers.

41. Prosthodontic management: Reservoir complete denture A saliva reservoir is a chamber incorporated into a removable prosthesis ,that provides a flow of salivary substitute for a certain period of time. The weight of a maxillary reservoir can hamper prosthesis retention. Saliva reservoirs range in volume from 2.3 mL to5.3 mL and provide a flow of artificial saliva for 2 to 5 hours.

42. © Springer International Publishing AG, part of Springer Nature 2018 281 Y. K. Özkan (ed.), Complete Denture Prosthodontics,

43. Salivary pacemakers First-generation electro stimulating devices – Salitron Removable intraoral appliance produced for individual patients by using their teeth pattern molds

44. Dental implant-based third-generation intraoral device Saliwell crowns

45. Conclusion The multi factorial role of salivary components continue to represent a focused area of dental research. The knowledge of normal salivary composition, flow & function is extremely important on a daily basis when treating patients. Dental health professionals spend untold hours removing this precious natural resource to perform therapy, with little regard to its value until flow is significantly reduced. Whether saliva occurs in quantities large or small , recognition should be given to the many contributions it makes to the preservation & maintenance of oral & systemic health

46. References Guyton and Hall textbook of medical physiology 13 th edition Grey’s anatomy 41 st edition © Springer International Publishing AG, part of Springer Nature 2018 281 Y. K. Özkan (ed.), Complete Denture Prosthodontics, Boucher’s complete denture prosthodontics,13 th edition SALIVARY GLANDS Adam R. Silvers, MD, and Peter M. Som, MD THE JOURNAL OF PROSTHETIC DENTISTRY VOLUME 85 NUMBER 2 Textbook of complete denture prosthodontics by Charles M. Heartwell Saliva in Prosthodontic Therapy – All You Need To Know! Smitha Annie Jacob, and Anoop Gopalakrishnan2

47. Thank you..!