Topical Hyaluronic Acid Adjunctive Effects on Healing After Free Gingival Grafting in Smokers and Non-Smokers

NCT ID: NCT07143760

Last Updated: 2025-08-27

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

80 participants

Study Classification

OBSERVATIONAL

Study Start Date

2018-01-01

Study Completion Date

2022-11-30

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Comparison of the healing of free gingival grafts applied to smokers and non-smokers and evaluation of the effect of hyaluronic acid gel on healing of the donor site.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

The oral mucosa consists of three main components: (1) masticatory mucosa, (2) specialized mucosa, and (3) lining mucosa. The masticatory mucosa is a keratinized tissue covering the gingiva and the hard palate. The gingiva itself can be classified into three distinct regions: (1) free gingiva, (2) interdental gingiva, and (3) attached gingiva. The free gingiva is composed of oral epithelium, oral sulcular epithelium, and junctional epithelium. Both the oral epithelium, interdental gingiva, and attached gingiva are keratinized tissues.

Keratinized gingiva can be histologically divided into the following cell layers based on the degree of keratin-producing cell differentiation:

Stratum basale (or stratum germinativum)

Stratum spinosum

Stratum granulosum

Stratum corneum

The absence of keratinized gingiva is classified under mucogingival deformities. These deformities represent deviations from the normal dimensional and morphological relationship between the gingiva and the alveolar mucosa and can often have negative esthetic and functional implications for patients. The lack of keratinized gingiva is addressed separately within mucogingival conditions.

In cases where patients present with a thin gingival biotype, inflammation and gingival recession can further reduce the protective capacity of the tissue, creating clinical scenarios in which mucogingival therapy should be considered. Lang and Löe suggested that an apico-coronal width of keratinized gingiva of less than 2 mm is insufficient to maintain gingival health. Today, the presence of attached gingiva is regarded as crucial for maintaining periodontal health. From a periodontal perspective, keratinized gingiva serves two primary functions:

Providing mechanical resistance against functional forces.

Offering a stable surface for toothbrushing, thus facilitating plaque control.

The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions concluded that, although a minimum amount of keratinized tissue may not be required to prevent attachment loss when optimal plaque control is achieved, approximately 2 mm of keratinized tissue and 1 mm of attached gingiva around the teeth is considered necessary to maintain periodontal health.

The Free Gingival Graft (FGG) procedure, first described by Björn in 1963, is a surgical technique developed to increase the dimensions of keratinized tissue around teeth and prevent gingival recession. This method remains one of the most commonly employed approaches for augmenting keratinized gingiva. However, over time, transplanted tissue can undergo horizontal and vertical dimensional changes. This makes the long-term volumetric stability of keratinized gingiva after FGG procedures critical. Postoperative graft shrinkage is considered a clinical phenomenon that mainly occurs during the early healing phase.

During FGG surgery, a graft is harvested from the palatal donor site, which is then left to heal by secondary intention. The most frequently observed postoperative complications at the donor site include pain, burning sensation, delayed wound healing, and associated difficulties in eating. Over the years, various hemostatic agents, periodontal dressings, platelet-rich fibrin, and analgesics have been used to reduce these complications and support healing; however, no ideal material has been identified in the literature.

The mechanisms by which smoking affects periodontal status are not fully understood, but numerous potential pathways have been discussed in the literature, including effects on the oral microbiota, gingival tissues, inflammatory and immune responses, and the healing capacity of the periodontium. Although smoking does not directly influence plaque accumulation, it is widely accepted that it can impair various aspects of the innate immune response. In periodontitis, the balance between plaque and immune response may shift toward exaggerated tissue destruction, meaning that even a small amount of plaque can lead to disproportionate breakdown.

Evidence suggests that, in smokers, the function and adhesion of gingival and periodontal ligament fibroblasts may be compromised, collagenolytic activity may increase, and collagen production may decrease. Additionally, the suppression of gingival inflammation, reduction in bleeding on probing, and decreased gingival bleeding seen in smokers are not due to vasoconstriction of the gingival vasculature but rather to reduced angiogenesis within the tissues.

For these reasons, mucogingival problems are more prevalent among smokers, with a clear dose-response relationship. Smoking may also negatively impact both the short- and long-term success of periodontal plastic surgery procedures. As a result, the expected dimensions of keratinized gingiva at the recipient site may not be achieved, and smokers may face a higher risk of postoperative complications.

In a study smoking did not appear to have a noticeable impact on postoperative dimensional changes of FGG, it was shown to reduce postoperative bleeding and delay epithelialization, ultimately slowing donor site wound healing.

Hyaluronic acid (HA) is a high-molecular-weight, non-sulfated polysaccharide of the glycosaminoglycan family, found in various body fluids such as synovial fluid, serum, saliva, and gingival crevicular fluid. HA is present in all periodontal tissues-at higher concentrations in non-mineralized tissues like the gingiva and periodontal ligament and at lower levels in mineralized tissues like cementum and alveolar bone. HA is synthesized by mesenchymal cells such as fibroblasts, chondrocytes, and osteoblasts at the cell membrane.

Because HA is highly biocompatible and non-immunogenic, it has bacteriostatic, fungistatic, anti-inflammatory, anti-edematous, osteoinductive, and pro-angiogenic properties, contributing to wound healing in various tissues. These properties have made HA an attractive adjunct in fields such as orthopedics, ophthalmology, and dermatology for treating a range of conditions.

In dentistry, HA has been applied to accelerate healing in extraction sockets, treat temporomandibular joint osteoarthritis, maintain space in sinus lift procedures without grafting, and relieve pain associated with recurrent aphthous ulcers. In periodontology, HA has been proposed for use either as a monotherapy or as an adjunct to non-surgical and/or surgical periodontal therapy to reduce inflammation and support wound healing.

To the best of our knowledge, there is no study in the literature evaluating the potential effects of HA on VAS scores and healing outcomes specifically in smokers undergoing FGG surgery.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Recession, Gingival Tissue Grafts

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

COHORT

Study Time Perspective

RETROSPECTIVE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Non-smokers who did not use Hyaluronic acid gel

This group consist subjects with Non-smokers who did not use Hyaluronic acid gel

No interventions assigned to this group

Non-smokers who used Hyaluronic acid gel

This group consist subjects with Non-smokers who used Hyaluronic acid gel

Gengigel

Intervention Type DEVICE

Free gingival graft (FGG) surgery leaves an open wound at the palatal donor site, which heals by secondary intention and can cause patient discomfort. Various adjunctive materials, such as stents, collagen sponges, platelet-rich fibrin, and hyaluronic acid (HA), have been explored to improve healing. HA is a naturally occurring glycosaminoglycan with hydrating, anti-inflammatory, and pro-regenerative properties that support fibroblast and keratinocyte activity and promote angiogenesis. These qualities make HA a promising adjunct for enhancing wound healing in periodontal surgery. However, few studies have assessed its clinical impact on palatal donor site healing after FGG, and in existing studies HA was applied only once by the operator rather than used consistently by patients. This study evaluates daily, patient-applied HA gel to address this gap and compare outcomes in smokers and non-smokers.

Smokers who did not use Hyaluronic acid gel

This group consist subjects with Smokers who did not use Hyaluronic acid gel

No interventions assigned to this group

Smokers who used Hyaluronic acid gel

This group consist subjects with Smokers who used Hyaluronic acid gel

Gengigel

Intervention Type DEVICE

Free gingival graft (FGG) surgery leaves an open wound at the palatal donor site, which heals by secondary intention and can cause patient discomfort. Various adjunctive materials, such as stents, collagen sponges, platelet-rich fibrin, and hyaluronic acid (HA), have been explored to improve healing. HA is a naturally occurring glycosaminoglycan with hydrating, anti-inflammatory, and pro-regenerative properties that support fibroblast and keratinocyte activity and promote angiogenesis. These qualities make HA a promising adjunct for enhancing wound healing in periodontal surgery. However, few studies have assessed its clinical impact on palatal donor site healing after FGG, and in existing studies HA was applied only once by the operator rather than used consistently by patients. This study evaluates daily, patient-applied HA gel to address this gap and compare outcomes in smokers and non-smokers.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Gengigel

Free gingival graft (FGG) surgery leaves an open wound at the palatal donor site, which heals by secondary intention and can cause patient discomfort. Various adjunctive materials, such as stents, collagen sponges, platelet-rich fibrin, and hyaluronic acid (HA), have been explored to improve healing. HA is a naturally occurring glycosaminoglycan with hydrating, anti-inflammatory, and pro-regenerative properties that support fibroblast and keratinocyte activity and promote angiogenesis. These qualities make HA a promising adjunct for enhancing wound healing in periodontal surgery. However, few studies have assessed its clinical impact on palatal donor site healing after FGG, and in existing studies HA was applied only once by the operator rather than used consistently by patients. This study evaluates daily, patient-applied HA gel to address this gap and compare outcomes in smokers and non-smokers.

Intervention Type DEVICE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

Patients were eligible for inclusion if they were between 18 and 65 years of age, systemically healthy, and not taking regular medication. Additional criteria included the absence of antibiotic use within the last three months, no pregnancy or lactation, a periodontally healthy status or completion of periodontal therapy, and the presence of insufficient keratinised gingiva in the mandibular anterior region (canine-to-canine) with a clinical indication for FGG in the same area. Smoking and non-smoking status were determined from clinical records and patient self-reports. All smokers included in the study continued smoking throughout the documented postoperative period, and none of the non-smokers had a history of smoking or initiated smoking during the study period.

Exclusion Criteria

Subjects who do not meet these conditions will not be included in the study.
Minimum Eligible Age

18 Years

Maximum Eligible Age

65 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Ricerfarma S.r.l

OTHER

Sponsor Role collaborator

Istanbul University

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Emine Çifcibaşı

Associate Professor

Responsibility Role PRINCIPAL_INVESTIGATOR

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Istanbul University, Dentistry Faculty, Department of Periodontology

Istanbul, , Turkey (Türkiye)

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Turkey (Türkiye)

References

Explore related publications, articles, or registry entries linked to this study.

Yildirim S, Ozener HO, Dogan B, Kuru B. Effect of topically applied hyaluronic acid on pain and palatal epithelial wound healing: An examiner-masked, randomized, controlled clinical trial. J Periodontol. 2018 Jan;89(1):36-45. doi: 10.1902/jop.2017.170105.

Reference Type BACKGROUND
PMID: 28914592 (View on PubMed)

Silva CO, Ribeiro Edel P, Sallum AW, Tatakis DN. Free gingival grafts: graft shrinkage and donor-site healing in smokers and non-smokers. J Periodontol. 2010 May;81(5):692-701. doi: 10.1902/jop.2010.090381.

Reference Type BACKGROUND
PMID: 20429648 (View on PubMed)

Hatipoglu H, Keceli HG, Guncu GN, Sengun D, Tozum TF. Vertical and horizontal dimensional evaluation of free gingival grafts in the anterior mandible: a case report series. Clin Oral Investig. 2007 Jun;11(2):107-13. doi: 10.1007/s00784-006-0084-x. Epub 2007 Feb 9.

Reference Type BACKGROUND
PMID: 17294229 (View on PubMed)

Cifcibasi E, Karabey V, Koyuncuoglu C, Duzagac E, Genceli E, Kasali K, Cintan S. Clinical evaluation of free gingival graft shrinkage in horizontal and vertical dimensions. J Istanb Univ Fac Dent. 2015 Oct 21;49(3):11-16. doi: 10.17096/jiufd.58759. eCollection 2015.

Reference Type BACKGROUND
PMID: 28955540 (View on PubMed)

Björn, H. (1963). Free Transplantation of Gingiva Propria. Odontol. Rev.

Reference Type BACKGROUND

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

2023/18

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.