Gingival PigmentationPhase 3NCT07810101
Evaluation of the Efficacy of Topical Application of Liquid Nitrogen and Ascorbic Acid in Treatment of Gingival Pigmentation
A Phase 3 study testing Topical application of ascorbic acid for treatment of gingival pigmentation, Topical application of liquid nitrogen for treatment of gingival pigmentation and Treatment of gingival pigmentation by surgical technique in people with Gingival Pigmentation and Gingiival Hyperpigmentation, run by Al-Azhar University at 1 site in Egypt.
Trial summary
Aim of study The present study will be designed to evaluate the clinical and histomorphometric outcomes of using topical liquid nitrogen and topical ascorbic acid in gingival depigmentation. Primary outcome: Clinical severity and extension of gingival pigmentation. Read more about this study
- Who is it for?
- Ages 18 to 40 years
- Conditions the study is for
- Gingival Pigmentation, Gingiival Hyperpigmentation
- What is being tested?
- Topical application of ascorbic acid for treatment of gingival pigmentation, Topical application of liquid nitrogen for treatment of gingival pigmentation and Treatment of gingival pigmentation by surgical technique
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteEgypt
- Study dates
- 1 Sep 2026to Apr 2027
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Individuals with mild-to-severe anterior melanin gingival pigmentation in the anterior portion of the upper and lower gingiva according to Dummet's classification will be involved.
- The patients included in this study will be Type 1 individuals according to American Society of Anesthesiology .
- The age of the patients ranges between 18 and 40 years.
Who cannot join
- smoker patients
- pregnant and lactating women
- patients with any systemic disease that may induce the production of melanin
- patients with periodontal disease, non vital anterior teeth
- patients with known hypersensitivity to ascorbic acid
- patients who had previous depigmentation procedures.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Egypt1 site
Faculty of dental medicine, Alazhar university, Assiut branch
Asyut, Asyut Governorate, 71511
About this study
Aim of study The present study will be designed to evaluate the clinical and histomorphometric outcomes of using topical liquid nitrogen and topical ascorbic acid in gingival depigmentation.
Primary outcome:
- Clinical severity and extension of gingival pigmentation.
Secondary outcome:
- Histologic assessment of the melanin forming cells.
Read the detailed description
Gingival hyperpigmentation is caused by excessive deposition of melanin in the basal and parabasal cell layers of the epithelium, it's mainly physiological due to the production of melanin. One of the factors that determines the colour of the gingiva is the amount of melanin pigment in the gingival epithelium. The intensity of melanin pigmentation differs from one person to another, and it is prevalent among all ethnicities. Gingival melanin pigmentation may cause esthetic concerns, even if no serious medical problem is present.
Gingival depigmentation can be defined as a periodontal plastic surgical procedure whereby the gingival hyperpigmentation is removed or reduced by various techniques. Depigmentation is not a clinical indication but a treatment of choice where esthetics is a concern and is desired by the patients.
A variety of depigmentation techniques can be classified into the following groups: surgical methods (Conventional techniques) as gingival abrasion and split thickness epithelial excision/scalpel, surgical technique/surgical stripping, electrosurgery, lasers, cryosurgery with liquid nitrogen, radiosurgery, and chemical methods using agents such as alcohols, phenols, and ascorbic acid.
Vitamin C, known as ascorbic acid, is used as a treatment modality in depigmentation of hyperpigmented spots on the skin and gingiva by inhibition of tyrosinase enzyme causing melanin biosynthesis suppression.
Vitamin C interacts with the copper (Cu) ions at the tyrosinase active site and inhibits the action of the enzyme tyrosinase, thereby reducing melanin formation. It also acts on the perifollicular pigment. However, it is an unstable compound. Therefore, it is used in combination with soy and liquorice for depigmentation in dermatology.
Advantages of cryotherapy include being a bloodless treatment, very low incidence of secondary infection and with a relative lack of scarring and pain. It provides a very good esthetic result and may be either the first choice or an alternative option to conventional surgery.
Cryotherapy with liquid nitrogen is the deliberate destruction of tissue by application of extreme cold that leads to freezing of pigmented cells.
- Conditions
- Gingival Pigmentation, Gingiival Hyperpigmentation
- Being tested
- Topical application of ascorbic acid for treatment of gingival pigmentation, Topical application of liquid nitrogen for treatment of gingival pigmentation, Treatment of gingival pigmentation by surgical technique
- Keywords
- liquid nitrogen and ascorbic acid in gingival depigentation, Liquid Nitrogen, ascorbic acid
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Topical application of ascorbic acid for treatment of gingival pigmentationDrug
topical application of ascorbic acid (non surgical technique ) for treatment of gingival pigmentation
Topical application of liquid nitrogen for treatment of gingival pigmentationCombination product
Topical application of liquid nitrogen (non surgical technique ) for treatment of gingival pigmentation
Treatment of gingival pigmentation by surgical techniqueProcedure or surgery
conventional technique for treatment of gingival pigmentation
| Study group | Role | What they receive |
|---|---|---|
| Patients will receive topical application of ascorbic acid | Active comparator | Not described Receives: Drug: Topical application of ascorbic acid for treatment of gingival pigmentation |
| Patients will receive topical application of liquid nitrogen | Active comparator | Not described Receives: Combination Product: Topical application of liquid nitrogen for treatment of gingival pigmentation |
| Patients will receive surgical depigmentation (conventional technique) | Active comparator | Not described Receives: Procedure: Treatment of gingival pigmentation by surgical technique |
What is being measured
The primary outcome is the main question the study is designed to answer.
Clinical severity of gingival pigmentation
DOPI index of gingival pigmentation (Dummett-Gupta Oral Pigmentation Index) sores the intensity of gingival pigmentation with scores ranges from 0 to 3, 0 = no pigmentation (pink gingiva) and 3 = heavy pigmentation (deep brown / blue - black gingiva).
Measured: 3 month follow up
Clinical severity of gingival pigmentation
DOPI index of gingival pigmentation
Measured: 3 month follow up
Secondary outcomes (1)
Histologic assessment of the melanin forming cells
Histologic assessment of the melanin forming cells by Hematoxylin and Eosin (H\&E) stain to veiw the melanocytes and the melanin pigentation in epithelium.
Measured: 3 month follow up
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Sep 2026
- Study start1 Sep 2026 (estimated)
- Primary completion1 Feb 2027 (estimated)
- Study completionApr 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Gingival PigmentationStudies of the same condition, open and under way.
- More trials run by Al-Azhar UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Al-Azhar University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Asmaa Mohamed Abdel Moniem Sayed, Al-Azhar University
- Investigators
- Ibrahim Hammad Ibrahim, assistant professor, Study director, ALAzhar U
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07810101
- Sponsor's protocol ID
- Liquid Nitrogen Depigmentation
- Status last verified
- Aug 2026
- First submitted
- 22 Aug 2026
- Last updated
- 9 Sep 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- Yes
- Individual data sharing
- No
Publications
Kamboj S, Salaria SK. Efficacy of liquid nitrogen and electrocautery assisted gingival depigmentation in term of patient's perception, histological wound healing - A randomized triple blind clinical trial. J Indian Soc Periodontol. 2020 Mar-Apr;24(2):135-144. doi: 10.4103/jisp.jisp_438_19. Epub 2020 Mar 2.
PubMed 32189841El-Mofty M, Elkot S, Ghoneim A, Yossri D, Ezzatt OM. Vitamin C mesotherapy versus topical application for gingival hyperpigmentation: a clinical and histopathological study. Clin Oral Investig. 2021 Dec;25(12):6881-6889. doi: 10.1007/s00784-021-03978-6. Epub 2021 May 8.
PubMed 33966113
Study at a glance
From the registry record, last updated by the sponsor on 9 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Efficacy of Topical Application of Liquid Nitrogen and Ascorbic Acid in Treatment of Gingival Pigmentation
- ClinicalTrials.gov ID
- NCT07810101
- Acronym / sponsor ID
- Liquid Nitrogen Depigmentation
- Conditions
- Gingival Pigmentation, Gingiival Hyperpigmentation
- Keywords
- liquid nitrogen and ascorbic acid in gingival depigentation, Liquid Nitrogen, ascorbic acid
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Al-Azhar UniversityUniversity, hospital or other
- Study start
- 1 Sep 2026 (estimated)
- Primary completion
- 1 Feb 2027 (estimated)
- Study completion
- Apr 2027 (estimated)
- First posted
- 9 Sep 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Aim of study The present study will be designed to evaluate the clinical and histomorphometric outcomes of using topical liquid nitrogen and topical ascorbic acid in gingival depigmentation.
Primary outcome:
- Clinical severity and extension of gingival pigmentation.
Secondary outcome:
- Histologic assessment of the melanin forming cells.
Detailed description
Gingival hyperpigmentation is caused by excessive deposition of melanin in the basal and parabasal cell layers of the epithelium, it's mainly physiological due to the production of melanin. One of the factors that determines the colour of the gingiva is the amount of melanin pigment in the gingival epithelium. The intensity of melanin pigmentation differs from one person to another, and it is prevalent among all ethnicities. Gingival melanin pigmentation may cause esthetic concerns, even if no serious medical problem is present.
Gingival depigmentation can be defined as a periodontal plastic surgical procedure whereby the gingival hyperpigmentation is removed or reduced by various techniques. Depigmentation is not a clinical indication but a treatment of choice where esthetics is a concern and is desired by the patients.
A variety of depigmentation techniques can be classified into the following groups: surgical methods (Conventional techniques) as gingival abrasion and split thickness epithelial excision/scalpel, surgical technique/surgical stripping, electrosurgery, lasers, cryosurgery with liquid nitrogen, radiosurgery, and chemical methods using agents such as alcohols, phenols, and ascorbic acid.
Vitamin C, known as ascorbic acid, is used as a treatment modality in depigmentation of hyperpigmented spots on the skin and gingiva by inhibition of tyrosinase enzyme causing melanin biosynthesis suppression.
Vitamin C interacts with the copper (Cu) ions at the tyrosinase active site and inhibits the action of the enzyme tyrosinase, thereby reducing melanin formation. It also acts on the perifollicular pigment. However, it is an unstable compound. Therefore, it is used in combination with soy and liquorice for depigmentation in dermatology.
Advantages of cryotherapy include being a bloodless treatment, very low incidence of secondary infection and with a relative lack of scarring and pain. It provides a very good esthetic result and may be either the first choice or an alternative option to conventional surgery.
Cryotherapy with liquid nitrogen is the deliberate destruction of tissue by application of extreme cold that leads to freezing of pigmented cells.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Patients will receive topical application of ascorbic acid | Active comparator | Drug: Topical application of ascorbic acid for treatment of gingival pigmentation |
| Patients will receive topical application of liquid nitrogen | Active comparator | Combination Product: Topical application of liquid nitrogen for treatment of gingival pigmentation |
| Patients will receive surgical depigmentation (conventional technique) | Active comparator | Procedure: Treatment of gingival pigmentation by surgical technique |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Individuals with mild-to-severe anterior melanin gingival pigmentation in the anterior portion of the upper and lower gingiva according to Dummet's classification will be involved.
- The patients included in this study will be Type 1 individuals according to American Society of Anesthesiology .
- The age of the patients ranges between 18 and 40 years.
Key exclusion criteria (6 listed)
- smoker patients
- pregnant and lactating women
- patients with any systemic disease that may induce the production of melanin
- patients with periodontal disease, non vital anterior teeth
- patients with known hypersensitivity to ascorbic acid
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Topical application of ascorbic acid for treatment of gingival pigmentationtopical application of ascorbic acid (non surgical technique ) for treatment of gingival pigmentation | Drug | Patients will receive topical application of ascorbic acid |
| Topical application of liquid nitrogen for treatment of gingival pigmentationTopical application of liquid nitrogen (non surgical technique ) for treatment of gingival pigmentation | Combination product | Patients will receive topical application of liquid nitrogen |
| Treatment of gingival pigmentation by surgical techniqueconventional technique for treatment of gingival pigmentation | Procedure or surgery | Patients will receive surgical depigmentation (conventional technique) |
Primary outcome
Clinical severity of gingival pigmentation
Time frame: 3 month follow up
DOPI index of gingival pigmentation (Dummett-Gupta Oral Pigmentation Index) sores the intensity of gingival pigmentation with scores ranges from 0 to 3, 0 = no pigmentation (pink gingiva) and 3 = heavy pigmentation (deep brown / blue - black gingiva).
Clinical severity of gingival pigmentation
Time frame: 3 month follow up
DOPI index of gingival pigmentation
1 secondary outcome
Histologic assessment of the melanin forming cells
Time frame: 3 month follow up
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Sep 2026.
- Background: PubMed 32189841Kamboj S, Salaria SK. Efficacy of liquid nitrogen and electrocautery assisted gingival depigmentation in term of patient's perception, histological wound healing - A randomized triple blind clinical trial. J Indian Soc Periodontol. 2020 Mar-Apr;24(2):135-144. doi: 10.4103/jisp.jisp_438_19. Epub 2020 Mar 2.
- Background: PubMed 33966113El-Mofty M, Elkot S, Ghoneim A, Yossri D, Ezzatt OM. Vitamin C mesotherapy versus topical application for gingival hyperpigmentation: a clinical and histopathological study. Clin Oral Investig. 2021 Dec;25(12):6881-6889. doi: 10.1007/s00784-021-03978-6. Epub 2021 May 8.
- Individual participant dataSharing planned: No
Related trials for Gingival Pigmentation
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Effect of Co-enzyme Q10 and Vitamin C Alone or in Combination After a Surgical Gingival Depigmentation
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Ibrahim Hammad Ibrahim, assistant professor study director
ALAzhar U
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Topical application of ascorbic acid for treatment of gingival pigmentation, Topical application of liquid nitrogen for treatment of gingival pigmentation and Treatment of gingival pigmentation by surgical technique in people with Gingival Pigmentation and Gingiival Hyperpigmentation, run by Al-Azhar University at 1 site in Egypt.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: enrolling by invitation, as of the sponsor's last update on 9 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Egypt. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Clinical severity of gingival pigmentation (time frame: 3 month follow up). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07810101, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Sep 2026.