Condition category
Oral Health
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
A gingival graft is a surgical procedure for patients with gingival recession (receding gums). It involves removing tissue from the patient's palate (palatal donor sites) and then grafting it onto the site of the recession (missing gum). Different graft harvesting procedures have been used. Wound healing and re-epithelialization are the most important factors which affect the level of discomfort (morbidity) that patients may feel. This study aims to assess re-epithelialization (healing) and wound closure of palatal donor sites after free gingival graft surgery with different graft sizes.

Who can participate?
Patients aged over 20 with gingival recession

What does the study involve?
Participants are randomly allocated to be treated with grafts of one of four different sizes. Re-epithelialization is assessed on the 7th, 14th, 21st, 28th, 35th, 42nd, 48th and 54th days after surgery using blue staining and taking photographs of the surgical sites.

What are the possible benefits and risks of participating?
Expected benefits from this study are receiving treatment for gingival recession, while the risks are pain, delayed bleeding and discomfort.

Where is the study run from?
Damascus University (Syria)

When is the study starting and how long is it expected to run for?
August 2018 to June 2019

Who is funding the study?
Damascus University (Syria)

Who is the main contact?
Dr Odai Al-Bashir

Trial website

Contact information



Primary contact

Dr Odai Al-Bashir


Contact details

Mashru' dimar
+963 (0)992219044

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number


Study information

Scientific title

Effect of graft dimensions on palatal wound re-epithelialization evaluated by toluidine blue stain


Study hypothesis

H0: There is no effect of the length and thickness of the free gingival graft on re-epithelialization.

Ethics approval

Approved 12/06/2018, University Of Damascus Dental School Local Ethics Committee (Damascus University, Damascus, Syria; +963 (0)94040840;, ref: 3137/t.m

Study design

Randomized control trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

No participant information sheet available


Mucogingival problems qualifying them for surgery: thin biotype, a narrow zone of keratinized gingiva (≤1 mm) and multiple gingival recession on the facial aspect of the mandibular anterior area


Following enrollment, participants are assigned to treatment groups using balanced block randomization. The surgeon, the observers and the patients are blinded. To meet the assumptions of randomization, a number of sealed non-transparent coded envelopes are prepared with letters A, B, C or D printed on them. Each patient is then required to choose one. If A is chosen, the patients are assigned to group L1. A patient choosing B is assigned to the group L2. Patients choosing C are assigned to group T1, while D is assigned to group T2.

In group L1 the graft is 10-15 mm long (16 patients) and in group L2 the graft is more than 15 mm long (16 patients). The width and thickness of the graft site are 8 mm and 1.5-2 mm. In group T1 the graft is ≤2 mm thick (16 patients) and in group T2 the graft is >2 mm thick (16 patients).

The graft is obtained from the distal part of the canine to the mesial part of the first molar and 2 mm apical to the gingival margin. The length and width of the graft site are 14 mm and 8 mm, respectively.

Re-epithelialization is assessed using 1% Toluidine Blue solution according to its application protocol. The patient is asked to rinse with water for 20 seconds to eliminate the food remnants, then to rinse with 1% acetic acid for 20 seconds to eliminate saliva components. 1% Toluidine Blue is then applied with a piece of cotton for 20 seconds. Then again, participants rinse with 1% acetic acid for 20 seconds. After that, a syringe is used to rinse for 20 seconds with sterilized water. When the wound turns a dark blue color, it indicates the staining of the connective tissue cells and the absence of the keratinized epithelium. A light blue color or the absence of the color indicates the formation of keratinized epithelium.

The results are recorded on the 7th, 14th, 21st, 28th, 35th, 42nd, 48th and 54th day post-surgery by taking standardized photographs of the surgical sites by using a specially designed device and a mouth mirror to ensure that the researchers had the same reference position during the follow-up period. Then each photograph is analyzed using computer software (Image National Institutes of Health, USA) to calculate the surface area of re-epithelialization.

Graft surface area is calculated directly after harvesting and it equals the wound surface area at baseline. The surface area of the dark blue color on the photograph is measured. Finally, the re-epithelialization surface area is calculated by subtracting the dark blue area from the total wound area.

Intervention type



Drug names

Primary outcome measure

Re-epithelialization assessed using Toluidine Blue staining on the 7th, 14th, 21st, 28th, 35th, 42nd, 48th and 54th day post-surgery

Secondary outcome measures

There are no secondary outcome measures

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Older than 20 years
2. Presenting bilateral class I or II Miller gingival recession in the mandibular incisor region
3. Included teeth are vital and have no caries or restorations
4. Plaque and the gingival index scores less than 1
5. Systematically healthy and non-smokers

Participant type


Age group




Target number of participants


Total final enrolment


Participant exclusion criteria

1. Periodontal probing depth higher than 3 mm
2. Patient receiving medical therapy that interferes with wound healing process
3. Pregnant and lactating woman
4. Patient with a previous surgical procedure in the study area and patients undergoing orthodontic therapy

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Damascus University
Faculty of Dental Medicine Al-Mazzah Highway

Sponsor information


Damascus University

Sponsor details

Al-Mazzah Highway
+963 (0)113341864

Sponsor type




Funder type


Funder name

Damascus University

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Planned publication in a high-impact peer-reviewed journal. Currently there are no additional documents for this trial.

IPD sharing statement
The data-sharing plans for the current study are unknown and will be made available at a later date.

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

27/08/2020: Trial's existence confirmed by University Of Damascus Dental School Local Ethics Committee.