1. MUCOSAL RESPONSE TO
ORAL PROSTHESES
SOME PATHOLOGICAL CONSIDERATIONS
-Aaron Sarwal

2. WHAT IS ORAL PROSTHESES?
• “Oral Prostheses” also known as “Dental
Prostheses” is a specialist area of
medicine which is concerned with the
recreation of the dentition when there
are missing or badly damaged teeth.
• It is covered under the „Prosthodontics‟
branch of Dentistry according to the
ADA.
• Prosthodontics is the dental specialty
pertaining to the diagnosis, rehabilitation Oral Prostheses
and maintenance of the oral
function, comfort, appearance and
health of patients with missing or
deficient teeth and/or oral and
maxillofacial tissues.

3. WHY AND HOW DOES ORAL PROSTHESES
CAUSE MUCOSAL PATHOLOGIES?
“
…the treatment
modalities
• Appliance put in oral cavity which deal with
1 the
replacement of
• Appliance surrounded by mucous missing teeth
2 membrane and contiguous
structures with a
• Disrupts normal oral conditions or suitable
3 oral environment prostheses can
be broadly
• Initiates response (pathological classified as
4 condition) removable and
fixed…
”

4. TYPES OF ORAL PROSTHESES
Removable Prostheses Fixed Prostheses
(Denture) (Implant)

5. WHAT MUCOSAL PATHOLOGIES DOES
ORAL PROSTHESES CAUSE?
Mucosal Pathologies of Oral Prostheses • Prostheses are
designed to
conserve the
remaining
Due to Removable Due to Fixed structures and
maintain them.
Mucosal Lesions Secondary Caries
• Prostheses act as
etiological
Burning Mouth Syndrome Pulpal and Periodontal Inflammation
factors either
due to error from
Allergic response Allergic Reactions operator, inadeq
uate
Fungal Infection
maintenance or
Occlusion Related Disorders
the properties of
the material
Trauma (metallic clasps) Periimplantitis itself.

6. DENTURE IN THE ORAL ENVIRONMENT
„Placement of Mechanical irritation
removable Mucosal Accumulation of
prostheses in the reactions microbial plaque
oral cavity Allergic reactions
produces Negative effect
Poor
profound function
on muscle
function
changes of the Denture in
oral environment the Oral Surface
Cavity Irregularities
Plaque formation
that may have and
Microporosities
an adverse
Local Increased
effect on the Irritation
permeability to
allergens
integrity of the
Bacteria use
Accumulate, form
oral tissues.‟ PMMA as
Bacterial plaque
Carbon source

7. INTERACTION OF PROSTHETIC MATERIAL WITH THE
ORAL ENVIRONMENT AND ITS CONSEQUENCES
• There are two types of consequences of prosthetic material in
the oral cavity:
1. Direct
2. Indirect
• These are results of interaction of prosthetic material with the
oral mucosa, and are influenced by:
a. Surface Properties: Chemical
stability, Adhesiveness, Texture,
Microporosities, Hardness
b. Chemical properties: Corrosion, Toxic Reactions, Allergic
Reactions
c. Physical properties: Mechanical irritation, Plaque
accumulation
d. Changes of environmental conditions: Plaque Microbiology

8. DIRECT CONSEQUENCES OF
WEARING DENTURES
PATHOLOGICAL CONSIDERATIONS

9. DENTURE STOMATITIS
Candida –
associated
if yeast is involved.
Type I Localized simple inflammation
Types and
Clinical
Denture Stomatitis
Presentations Type II
Generalized diffuse erythema in part or
entire denture-covered area.
Granular type involves central hard palate
Type III and the alveolar ridges. Seen in association
with type I or type II.
Strains of genus Candida, in
Candida – particular Candida
associated Albicans , cause denture
stomatitis.
trauma induced, caused by microbial
Causes Type I, II and III plaque accumulation (bacteria or
yeast) on denture surface.
Candida associated Angular chelitis or glossitis due to infection
denture stomatitis from denture covered mucosa to angles of
and angular chelitis the mouth or tongue.

10. FLABBY RIDGE
Clinical Presentations:
•Alveolar ridge mobile, extremely resilient.
•anterior part of maxilla, when remaining anterior teeth in mandible.
Histology:
•Marked fibrosis and inflammation, and resorption of the underlying bone.
Causes:
•Replacement of bone by fibrous tissue.
•Excessive load of the residual ridge
•Unstable occlusal conditions.
Problems and Suggested Solutions:
•Provides poor support of the dentures.
•removed surgically to provide the stability required by dentures.
•extreme cases, total removal not done, leads to elimination of vestibular sulcus.
•Resilient ridges provide some support for retention.

11. DENTURE IRRITATION HYPERPLASIA
•Hyperplasia of mucosa
•Lesions single/ numerous/ consist of
flaps of connective tissue.
Clinical
•Development of elongated rolls of
Presentations tissue in mucofacial folds.
•Inflammation is variable, deeper fissures
severe with ulceration.
•Cells resemble normal cells, great
Histology increase in number.
•Main cause ill-fitting denture
Causes •Lesions result of chronic injury by thin,
over extended denture flanges.
•Replacement or adjustment of the
Problems and denture, produces some clinical
improvement
Suggested •Post surgical excision of the
Solutions tissue, replacement of denture, lesions
are unlikely to reoccur. Histology

12. TRAUMATIC ULCERS
Clinical Presentations:
• „Sore spots in one to three days after new dentures.
• Ulcers small, painful, covered gray necrotic membrane, surrounded by
inflammatory halo with firm, elevated borders.
Histology:
• Patient adapts to the condition, may develop into denture irritation
hyperplasia.
Causes:
• Result of overextended denture flanges or unbalanced occlusion.
Notes:
• Suppression of mucosal resistance to mechanical irritation is predisposing
e.g., diabetes mellitus and vitamin deficiency.
• Normally, the sore spots heal in a few days.

13. ANGULAR CHEILITIS
•Multifactorial disease, seen in denture wearers, adults and children.
•Feeling of dryness and burning sensation at the ends of the mouth
Clinical
•Skin at the commissure appears wrinkled and macerated, even
Presentations: ulcerated, never bleeds, crust may form.
•Lesions stop at the mucocutaneous junction.
Histology: •Majority are Candida associated.
•A result overextended denture flanges or unbalanced occlusion.
Causes: •In patients with loss of vertical dimension, deep folds of skin are produced
at the corners of the mouth. Saliva collects in this area, the skin becomes
cracked, macerated.
•Variable due to varied etiology, any infection present is secondary for
Treatment: permanent cure, the primary cause must be corrected.
•The lesions rarely completely disappear, usually reoccur in minor form.
•A clinical diagnosis should only be arrived at after other lesions like due
to known trauma, syphilis etc. are ruled out.
Notes:
•Often associated with many other factors like infection and vitamin
deficiency( esp Vit B) and loss of vertical dimension

14. ORAL CANCER IN DENTURE WEARERS
An association between the chronic irritation of the oral mucosa
by dentures and oral cancer has been claimed, however, no
definite proof exists.
Reports have detailed the development of oral
carcinomas in patients who wear ill-fitting dentures.
The opinion is still valid that if a sore spot does not
heal for long, malignancy may be suspected.
Patients with such lesions should be immediately
referred to a pathologist.
Prognosis is poor for oral cancers, especially the ones in
the floor of the mouth.

15. BURNING MOUTH SYNDROME (BMS)
Clinical Presentations: Causes:
Moderate to severe burning in the mouth is
Damage to nerves that control
the main symptom of BMS and can persist for pain and taste
months or years.
Hormonal changes
For many people, the burning sensation begins in
late morning, builds to a peak by evening, and Dry mouth, which can be caused by
often subsides at night. Some feel constant pain; for many medicines and disorders such as
others, pain comes and goes. diabetes, nutritional deficiencies
Oral candidiasis, a fungal
Oral mucosa appears healthy clinically. infection in the mouth
Other symptoms of BMS include: Acid reflux
•Tingling or numbness on the tip of the tongue or in
the mouth
•Bitter or metallic changes in taste
Poorly-fitting dentures or allergies
•Dry or sore mouth. to denture materials

16. BURNING MOUTH SYNDROME (BMS)
•Adjusting/replacing irritating dentures
•Treat existing disorders e.g. diabetes, supplements for
nutritional deficiencies
Treatment:
•Switching medicine, if a drug is causing BMS
•prescribing medications to
•Relieve dry mouth
•Treat oral candidiasis
•Help control pain from nerve damage
•Relieve anxiety and depression.
•Anxiety and depression result from chronic pain.
•May have more than one cause.
•Mostly, the exact cause of symptoms cannot be
found.
Notes: •Treatment tailored to ones individual needs.
•If no cause can be found, aim is to try to reduce
the pain associated with burning mouth
syndrome.

17. GAGGING AND RESIDUAL RIDGE
REDUCTION
GAGGING: RESIDUAL RIDGE REDUCTION
•Normal, healthy defense •Studies have established a continuous loss
mechanism, prevents foreign bodies from of the bone tissue after teeth extraction
entering trachea and the placement of complete dentures.
•Many stimuli cause gagging, such as •The resorption rate varies by individual.
irritation of the posterior part of the •Some say that RRR is physiological process
tongue, soft palate, even sights, tastes etc. that occurs because the use of the alveolar
can cause gagging bone is lost after tooth extraction, however,
•Due to dentures, patient may gag initially RRR can proceed to the basal bone and
but gets accustomed. hence is believed to be a pathological
•Gaging may also be a symptom of process and not a physiological one.
disorders and diseases of the GIT, adenoids
or catarrh in the upper respiratory passage.

18. OVERDENTURE ABUTMENTS : CARIES
AND PERIODONTAL DISEASE
 The retention of selected teeth to serve
as abutments under complete dentures
is an excellent prosthodontic technique.
 However, bacterial colonization
beneath a close fitting denture is
enhances and leads to caries, due to
microbial plaque of Streptomyces and
Actinomyces (predominantly).
 If the plaque is left undisturbed, it initiates
gingivitis in one to three days.
 Patients with overdentures demonstrate
up to 30% increase in caries within one
year.
 Preventive measures should be aimed at
preventing the accumulation of plaque
near the roots.

19. INDIRECT CONSEQUENCES
OF WEARING DENTURES
PATHOLOGICAL CONSIDERATIONS

20. ATROPHY OF MASTICATORY MUSCLES AND
MASTICATORY ABILITY AND PERFORMANCE
Essential that masticatory function (in complete
denture wearers) be maintained through out life.
Masticatory function depends on the skeletal
muscular force and the ability to co-ordinate oral
functional movements during mastication.
Maximal bite forces decrease in older patients.
Greater atrophy occurs in complete denture wearers
especially women.
Little evidence that new dentures reduce this
atrophy.
Wearing dentures does compromise masticatory performance greatly
as compared to a natural set of teeth
Masticatory ability:
• it is an individual‟s own assessment of his/her
masticatory function
Masticatory efficiency:
• it is the capacity to grind the food during
mastication.

21. NUTRITIONAL DEFICIENCIES
• Aging is often associated with a significant decrease in
energy needs as a consequence of decline in muscle
mass and decreased physical activity.
• There is a 30% fall in the energy however, with the
exception of carbs, the nutritional requirement doesn't
decrease with age.
• As a result dietary intake of elder individuals often
reveals evidence of deficiencies clearly related to
dental/ prosthetic status.
• Severe nutritional deficiencies are rare in the
healthy, even with impaired masticatory functions, it is
only in hospitalized/ chronically ill patients that inability to
chew and altered taste perception lead to negative
dietary habits and nutritional status.

22. ALLERGIC REACTIONS: INTRAORAL
CONTACT ALLERGY REACTIONS
•Poorly understood , not very commonly dealt with in specialized literature.
•No single or specific clinical picture of IOCA, lichenoid reactions common.
•Metals used in dental practice – e.g. amalgams ,Ni base metal alloys-
cause IOCA reactions, hypersensitivity consequence of increasingly
widespread use.
•Common allergens: 2-HEMA (hydoxyethyl methacrylate) and triethylene
glycol dimethacrylate.
•Methacrylates have rarely cause oral lichenoid reactions.
•Dental amalgams are the most common cause of IOCA.
•No single or pathognomic IOCA lesion exists.
•Replacement of restorations containing materials that give a positive
epicutaneous test is not warranted.
•Allergy due to many nonspecific or unclear intraoral clinical disorders.
Generalized gingivitis as a symptom of
IOCA to othodontic metals

23. PERIIMPLANTITIS
• Soft and hard tissues surrounding osseointegrated implant
show similarities with periodontium.
• Big difference in the collagen fibers being non-attached
and parallel to implant surface instead of being
perpendicular and in functional arrangement from bone
to cementum.
• Periodontitis like process- periimplantitis affects implants
and leads to loss osseointegrated implant.
• Bacteria play significant role in this, similar to periodontitis,
failing implants include gingival inflammation, deep
pockets and bone loss.
• Bacterial flora is gram negative rods e.g. Bacteroides and
Fusobacterium sps.
• Probing depths > 6mm and periimplant radiolucency.

24. PERIIMPLANTITIS
• Etiology is either infection with periodontal
pathogens of increased trauma
(retrograde periimplantitis).
• Implants have less effective soft tissue
barrier around their necks than natural
teeth, less resistant to infection.
• The micro flora associated with failing
implants is similar to that of periodontally
affected teeth.
• Treatment involves determination of the
etiology, it‟s control along with hygiene
techniques, instrumentation and use of
antimicrobials.

25. CONCLUSION
• „Placement of removable prostheses in the oral cavity
produces profound changes of the oral environment that may
have an adverse effect on the integrity of the oral tissues.‟
(Mahesh Verma, Shafers‟s)
• Mucosal reactions occur from the mechanical
irritation, accumulation of microbial plaque and occasionally
due to allergic reactions.
• Dentures that function poorly may act as negative factors in
muscle function
• Surface irregularities and micro porosities can greatly
encourage plaque formation.
• At times, the local irritation may end up increasing the
permeability of the mucosa to allergens, hence making it
difficult to distinguish between simple irritation and an allergic
response.
• Some bacteria can use the PMMA as a carbon source and
hence the accumulation of bacterial plaque at the interface
of the denture and mucosa causes several negative effects.

26. RESOURCES
• Appendix II, Shafer‟s Textbook of Oral Pathology.
(“Mucosal Response To Oral Prostheses: Some Pathological
considerations” - Dr. Mahesh Verma)
• Image credits:
Internet (http://www.google.co.in/imghp?hl=en&tab=wi)
• General research on the web was also done in making this
presentation just to confirm the information and update it where
required.
• Burning Mouth Syndrome slide source:
http://www.nidcr.nih.gov/OralHealth/Topics/Burning/BurningMou
thSyndrome.htm

27. Special thanks to :
Dr. Rupinder Kaur
(Ex-Lecturer,
Department of Dental
Anatomy and Oral
Pathology, Gian Sagar
Dental College and
Hospital)