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Gingival
De-Pigmentation
Gingival
De-Pigmentation
Introduction
Pigmentation :
āž¢The natural coloring of animal or plant tissue;
āž¢Abnormal coloring of personā€™s skin, typically
resulting from diseases.
Gingival Pigmentation is a discoloration of
oral mucosa or gingiva due to the wide
variety of lesions and conditions.
Most pigmentation is caused by 5 primary pigments
:
1. Melanin
2. Melanoid
3. Oxy-Hemoglobin
4. Reduced Hemoglobin
5. Carotene
Other agents :
1. Bilirubin
2. Iron
Melanin
Melanin (Greek: ĀµĪ­Ī»Ī±Ļ‚ - melas, "black, dark") is a
broad term for a group of natural pigments found in most
organisms (arachnids are one of the few groups in which it
has not been detected).
Melanin is produced by the oxidation of the amino
acid tyrosine.
The pigment is produced in a specialized group of
cells known as melanocytes.
There are three basic types of melanin:
1. eu-melanin (most common)
2. pheo-melanin (Brown & black, red hair)
3. neuro-melanin (Brain)
Melanin
In
Gingiva ?
ā€¢ Melanin is produced by
Melanocytes
ā€¢ Location : Basal layer.
ā€¢ Round Nucleus
ā€¢ Clear Cytoplasm
ā€¢ Lack Desmosomes
Melanoid
ā€¢ Location : stratum lucidum and stratum corneum.
ā€¢ Initially, it was assumed that melanoid was a
degradation product of melanin but more recently it
has been shown that such a relationship is highly
improbable.
ā€¢ Melanoid imparts a clear yellow shade to the skin.
The Journal of Contemporary Dental Practice, Vol. 4 No.3 Aug. 15, 2013
Oxy-hemoglobin
&
Reduced Hemoglobin
These are pigments resulting from
hemosiderin deposits
(Hemosiderin or haemo-siderin is an iron-storage complex. It is only found within cells)
Carotene
Location : stratum corneum & stratum lucidum.
Function : Gives a deep yellow color of the skin.
Women ā€ŗ Men
Clinical
Characteristics
ā€¢ Gingiva : Pigmented intraoral tissue.
ā€¢ Microscopically : melanoblasts are normally
present in basement (basal) layers of the lamina
propria.
ā€¢ Location : Attached gingiva.
ā€¢ The total number of melanophores in the attached
gingiva was approximately 16 times greater than in
the free gingiva.
ā€¢ Shades of pigmented gingiva :
1. Very Dark brown to Black
2. Brown
3. Light-Brownish Yellow
ā€¢ No Medical Problem.
ā€¢ Esthetic problems.
Causes
of
Pigmentation
Causes of Pigmentation :
1. Systemic Causes
2. Local Causes
Many systemic & local factors are responsible for causing
gingival Pigmentation.
Some of the very important factors are :
1. Amalgam Tattoo
2. Pigmented Nevi
3. Oral Melanotic Macules
4. Melanoma
5. Smokerā€™s Melanosis
6. Heavy Metals
7. Minocycline
8. Hemochromatosis
Amalgam Tattoo
āœ“The pigmentation of the oral mucosa membrane by tooth
restoration material (amalgam) is a common finding in
dental practice.
āœ“Amalgam pigmentation is generally called ā€œAmalgam
Tattooā€.
āœ“The lesions represents embedded amalgam particles &
usually manifests itself as an isolated bluish or black
macule in various areas of the mucosa.
āœ“Color : Black, Blue, grey or a combination of these.
Pigmented Nevi
ā€¢ Uncommon.
ā€¢ The Pigmented Nevi are classified as intramucosal,
junctional compound or Blue according to their
histological features.
ā€¢ Nevi are seen mostly on the vermillion border of the lips
& the gingiva.
ā€¢ Color : Grey, Brown, or bluish macules and are typically
asymptomatic.
Oral Melanotic
Macules
ā€¢ Rare oral mucosal lesion.
ā€¢ Synonyms : Ephelis,
melonosis, lentigo, solitary
labial lentigo, labial
melanotic macule & oral
melanotic macule.
ā€¢ Involvement : Vermillion
Border of the lower lip.
Melanoma
ā€¢ Cancerous condition of the
melanocytes.
ā€¢ Melanocytes are found
among the basal cells of the
epidermis.
ā€¢ Great majority : On the
palate, upper gingival &
alveolar mucosa.
Smokerā€™s Melanosis
ā€¢ Benign focal pigmentation of oral mucosa &It tends to increase with
tobacco consumption.
ā€¢ Clinically : Multiple brown pigmented macules.
ā€¢ Location : Attached labial-anterior gingival and the interdental
papilla of the mandible.
Heavy Metal Pigmentation
A b s o r b e d s y s t e m i c a l l y f r o m
therapeutic use or occupational
environments may discolor gingiva,
and other areas of the oral mucosa.
Metals :
1. Bismuth
2. Arsenic
3. Mercury : Blackish Blue color of
the gingiva.
4. Lead : Bluish red or deep Blue.
5. Silver : Violet marginal line or
Bluish grey discoloration.
Lead Poisoning
Minocycline Pigmentation
ā€¢ Causes discoloration of
Bones & teeth, but also
r e s p o n s i b l e f o r
discoloration of gingival
mucosa.
ā€¢ Color : Brown.
ā€¢ Mostly seen as Brownish
melanin deposits on the
hard palate, gingiva,
mucous membrane and the
tongue.
Hemo-chromatosis
ā€¢ Also k/a Bronze Diabetes.
ā€¢ Characterized by the deposition
of excess iron in the body
tissues, resulting in fibrosis and
functional insufficiency of the
involved organ.
ā€¢ Hyper-pigmentation may appear
on both skin & mucosa
membranes.
Treatment
of
Gingival
Pigmentation
Techniques Employed for Gingival
Depigmentation
Surgical Method :
1. Scalpel Surgical Technique
2. Cryosurgery
3. Electro surgery
4. Lasers :
a. Nd:Al:Yttrium-Gamet
b. Erbium-YAG Lasers
c. Carbon Di-Oxide Lasers
Methods Aimed at masking the Pigmented Gingiva with Grafts from Less Pigmented
Areas :
1. Free Gingival Grafts
2. Connective Tissue Grafts
3. Acellular Dermal Matrix Allografts.
Scalpel Surgical Technique
PROCEDURE :
ā€¢ Local Anesthesia
ā€¢ CEJ determined by probing around the labial and lingual
surfaces of each tooth.
ā€¢ Bleeding points created by the pocket marker taken as
reference points for placing the external Bevel Incision.
ā€¢ Knife : Kirkland Knife
ā€¢ Incision made : From the attached gingiva to a level just
apical to the pocket margin.
Periodontal dressing. : 2 weeks
post-surgical procedure.
FINAL HEALING :ā€œPale Pinkā€
(a) (b)
(c)
Scraping : Scalpel Surgical Technique
Gingival-Abrasion Technique
Cryo-Surgical
Depigmentation
Direct application of liquid nitrogen with a
cotton swab to the gingiva (pigmented area).
Tetrafluroethane (TfE) was commonly used
in cryosurgery for depigmentation.
ā€¢ Freezing zone :
30 to 40 seconds.
ā€¢ Procedure :
15 to 20 minutes.
Lasers
Lasers
The use of LASERs has also been proposed for the
management of oral melanin pigmentation.
The Nd:YAG LASER with an invisible, near-infra-red light
(wavelength of 1,064 nm) has a high affinity for dark
pigments, making it particularly suited for depigmentation.
CLASSSIFICATION OF LASERS
Gas lasers-
ā€¢ Argon
ā€¢ Carbon dioxide laser
Solid state lasers-
1. Nd:YAG Laser
2. Ho:YAG Laser
3. Er:YAG Laser
4. DIODE Laser
Mechanism of Laser on Soft
Tissues
A highly focused laser beam vaporizes the
soft tissue with the high water content. Laser can make very
small incisions when the beam is focused on the tissue.
When the beam is defocused, the intensity of the
laser light on the tissue diminishes, and it can be used for
cauterization of small blood vessels and lymphatics, therefore
decreases post-operative swellings.
Probably most important, the laser decreases
post-operative pain by sealing nerve endings.
Surgical laser systems are differentiated not
only by the wavelength, but also by the light delivery
system: flexible fiber or articulated arm, as well as by other
factors.
Soft-tissue laser surgery is differentiated from hard-
tissue laser surgery (bones and teeth in dentistry) and Laser
Eye Surgery (eyesight corrective surgeries) by the type of
lasers used in a particular type of laser surgery.
A laser scalpel is a scalpel for surgery, cutting
or ablating living biological tissue by the energy
of laser light.
In soft tissue laser surgery, a laser beam ablates or vaporizes
the soft tissue with high water content.
Advantages
1. Dry surgical field and better visualization.
2. Tissue surface sterilization and reduction in bacteria.
3. Decreased swelling, edema and scarring.
4. Decreased pain.
5. Faster healing response.
6. Increased patient acceptance.
7. Minimal mechanical trauma.
8. Negotiates folds in tissues.
Naik VK, Sangeetha S & Victor DJ (2010), Journal of Dental Sciences 1, 91-8.
Disadvantages
1. Expensive.
2. Require specialized training.
3. Dental instruments mainly used are both side and end
cutting thus; a modification of clinical technique is
required.
4. No single wavelength will optimally treat all dental
disease.
5. There is inability to remove metallic and cast-porcelain
defective restorations.
6. Harmful to eyes and skin.
Coluzzi DJ & Swick MD http://www.henryschein.com/usen/images/Dental/ CEHP/LaserinDentistry.pdf (accessed 14 March 2013)
Gingival De-Pigmentation

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Gingival De-Pigmentation

  • 3. Introduction Pigmentation : āž¢The natural coloring of animal or plant tissue; āž¢Abnormal coloring of personā€™s skin, typically resulting from diseases. Gingival Pigmentation is a discoloration of oral mucosa or gingiva due to the wide variety of lesions and conditions.
  • 4. Most pigmentation is caused by 5 primary pigments : 1. Melanin 2. Melanoid 3. Oxy-Hemoglobin 4. Reduced Hemoglobin 5. Carotene Other agents : 1. Bilirubin 2. Iron
  • 5. Melanin Melanin (Greek: ĀµĪ­Ī»Ī±Ļ‚ - melas, "black, dark") is a broad term for a group of natural pigments found in most organisms (arachnids are one of the few groups in which it has not been detected). Melanin is produced by the oxidation of the amino acid tyrosine. The pigment is produced in a specialized group of cells known as melanocytes.
  • 6. There are three basic types of melanin: 1. eu-melanin (most common) 2. pheo-melanin (Brown & black, red hair) 3. neuro-melanin (Brain)
  • 8. ā€¢ Melanin is produced by Melanocytes ā€¢ Location : Basal layer. ā€¢ Round Nucleus ā€¢ Clear Cytoplasm ā€¢ Lack Desmosomes
  • 9. Melanoid ā€¢ Location : stratum lucidum and stratum corneum. ā€¢ Initially, it was assumed that melanoid was a degradation product of melanin but more recently it has been shown that such a relationship is highly improbable. ā€¢ Melanoid imparts a clear yellow shade to the skin. The Journal of Contemporary Dental Practice, Vol. 4 No.3 Aug. 15, 2013
  • 10. Oxy-hemoglobin & Reduced Hemoglobin These are pigments resulting from hemosiderin deposits (Hemosiderin or haemo-siderin is an iron-storage complex. It is only found within cells)
  • 11. Carotene Location : stratum corneum & stratum lucidum. Function : Gives a deep yellow color of the skin. Women ā€ŗ Men
  • 13. ā€¢ Gingiva : Pigmented intraoral tissue. ā€¢ Microscopically : melanoblasts are normally present in basement (basal) layers of the lamina propria. ā€¢ Location : Attached gingiva. ā€¢ The total number of melanophores in the attached gingiva was approximately 16 times greater than in the free gingiva.
  • 14. ā€¢ Shades of pigmented gingiva : 1. Very Dark brown to Black 2. Brown 3. Light-Brownish Yellow ā€¢ No Medical Problem. ā€¢ Esthetic problems.
  • 16. Causes of Pigmentation : 1. Systemic Causes 2. Local Causes Many systemic & local factors are responsible for causing gingival Pigmentation. Some of the very important factors are : 1. Amalgam Tattoo 2. Pigmented Nevi 3. Oral Melanotic Macules 4. Melanoma 5. Smokerā€™s Melanosis 6. Heavy Metals 7. Minocycline 8. Hemochromatosis
  • 17. Amalgam Tattoo āœ“The pigmentation of the oral mucosa membrane by tooth restoration material (amalgam) is a common finding in dental practice. āœ“Amalgam pigmentation is generally called ā€œAmalgam Tattooā€. āœ“The lesions represents embedded amalgam particles & usually manifests itself as an isolated bluish or black macule in various areas of the mucosa. āœ“Color : Black, Blue, grey or a combination of these.
  • 18.
  • 19. Pigmented Nevi ā€¢ Uncommon. ā€¢ The Pigmented Nevi are classified as intramucosal, junctional compound or Blue according to their histological features. ā€¢ Nevi are seen mostly on the vermillion border of the lips & the gingiva. ā€¢ Color : Grey, Brown, or bluish macules and are typically asymptomatic.
  • 20.
  • 21. Oral Melanotic Macules ā€¢ Rare oral mucosal lesion. ā€¢ Synonyms : Ephelis, melonosis, lentigo, solitary labial lentigo, labial melanotic macule & oral melanotic macule. ā€¢ Involvement : Vermillion Border of the lower lip.
  • 22. Melanoma ā€¢ Cancerous condition of the melanocytes. ā€¢ Melanocytes are found among the basal cells of the epidermis. ā€¢ Great majority : On the palate, upper gingival & alveolar mucosa.
  • 23. Smokerā€™s Melanosis ā€¢ Benign focal pigmentation of oral mucosa &It tends to increase with tobacco consumption. ā€¢ Clinically : Multiple brown pigmented macules. ā€¢ Location : Attached labial-anterior gingival and the interdental papilla of the mandible.
  • 24. Heavy Metal Pigmentation A b s o r b e d s y s t e m i c a l l y f r o m therapeutic use or occupational environments may discolor gingiva, and other areas of the oral mucosa. Metals : 1. Bismuth 2. Arsenic 3. Mercury : Blackish Blue color of the gingiva. 4. Lead : Bluish red or deep Blue. 5. Silver : Violet marginal line or Bluish grey discoloration. Lead Poisoning
  • 25. Minocycline Pigmentation ā€¢ Causes discoloration of Bones & teeth, but also r e s p o n s i b l e f o r discoloration of gingival mucosa. ā€¢ Color : Brown. ā€¢ Mostly seen as Brownish melanin deposits on the hard palate, gingiva, mucous membrane and the tongue.
  • 26. Hemo-chromatosis ā€¢ Also k/a Bronze Diabetes. ā€¢ Characterized by the deposition of excess iron in the body tissues, resulting in fibrosis and functional insufficiency of the involved organ. ā€¢ Hyper-pigmentation may appear on both skin & mucosa membranes.
  • 28. Techniques Employed for Gingival Depigmentation Surgical Method : 1. Scalpel Surgical Technique 2. Cryosurgery 3. Electro surgery 4. Lasers : a. Nd:Al:Yttrium-Gamet b. Erbium-YAG Lasers c. Carbon Di-Oxide Lasers Methods Aimed at masking the Pigmented Gingiva with Grafts from Less Pigmented Areas : 1. Free Gingival Grafts 2. Connective Tissue Grafts 3. Acellular Dermal Matrix Allografts.
  • 29. Scalpel Surgical Technique PROCEDURE : ā€¢ Local Anesthesia ā€¢ CEJ determined by probing around the labial and lingual surfaces of each tooth. ā€¢ Bleeding points created by the pocket marker taken as reference points for placing the external Bevel Incision. ā€¢ Knife : Kirkland Knife ā€¢ Incision made : From the attached gingiva to a level just apical to the pocket margin.
  • 30.
  • 31.
  • 32.
  • 33. Periodontal dressing. : 2 weeks post-surgical procedure.
  • 35. (a) (b) (c) Scraping : Scalpel Surgical Technique
  • 37. Cryo-Surgical Depigmentation Direct application of liquid nitrogen with a cotton swab to the gingiva (pigmented area). Tetrafluroethane (TfE) was commonly used in cryosurgery for depigmentation.
  • 38.
  • 39.
  • 40.
  • 41.
  • 42. ā€¢ Freezing zone : 30 to 40 seconds. ā€¢ Procedure : 15 to 20 minutes.
  • 44. Lasers The use of LASERs has also been proposed for the management of oral melanin pigmentation. The Nd:YAG LASER with an invisible, near-infra-red light (wavelength of 1,064 nm) has a high affinity for dark pigments, making it particularly suited for depigmentation.
  • 45. CLASSSIFICATION OF LASERS Gas lasers- ā€¢ Argon ā€¢ Carbon dioxide laser Solid state lasers- 1. Nd:YAG Laser 2. Ho:YAG Laser 3. Er:YAG Laser 4. DIODE Laser
  • 46. Mechanism of Laser on Soft Tissues A highly focused laser beam vaporizes the soft tissue with the high water content. Laser can make very small incisions when the beam is focused on the tissue. When the beam is defocused, the intensity of the laser light on the tissue diminishes, and it can be used for cauterization of small blood vessels and lymphatics, therefore decreases post-operative swellings. Probably most important, the laser decreases post-operative pain by sealing nerve endings.
  • 47. Surgical laser systems are differentiated not only by the wavelength, but also by the light delivery system: flexible fiber or articulated arm, as well as by other factors. Soft-tissue laser surgery is differentiated from hard- tissue laser surgery (bones and teeth in dentistry) and Laser Eye Surgery (eyesight corrective surgeries) by the type of lasers used in a particular type of laser surgery. A laser scalpel is a scalpel for surgery, cutting or ablating living biological tissue by the energy of laser light. In soft tissue laser surgery, a laser beam ablates or vaporizes the soft tissue with high water content.
  • 48. Advantages 1. Dry surgical field and better visualization. 2. Tissue surface sterilization and reduction in bacteria. 3. Decreased swelling, edema and scarring. 4. Decreased pain. 5. Faster healing response. 6. Increased patient acceptance. 7. Minimal mechanical trauma. 8. Negotiates folds in tissues. Naik VK, Sangeetha S & Victor DJ (2010), Journal of Dental Sciences 1, 91-8.
  • 49. Disadvantages 1. Expensive. 2. Require specialized training. 3. Dental instruments mainly used are both side and end cutting thus; a modification of clinical technique is required. 4. No single wavelength will optimally treat all dental disease. 5. There is inability to remove metallic and cast-porcelain defective restorations. 6. Harmful to eyes and skin. Coluzzi DJ & Swick MD http://www.henryschein.com/usen/images/Dental/ CEHP/LaserinDentistry.pdf (accessed 14 March 2013)