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Clinical Evaluation of Different Treatments for Interdental Black Triangles

Efficacy of Nonsurgical Versus Surgical Management of Black Triangles: A Randomized Clinical Trial

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07548203
Acronym
BT-RCT
Enrollment
30
Registered
2026-04-23
Start date
2026-04-22
Completion date
2026-10-15
Last updated
2026-04-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Black Triangles Syndrome (BTS), Papilla Reconstruction

Brief summary

This randomized clinical trial aims to evaluate and compare the effectiveness of surgical and nonsurgical treatment approaches for the management of interdental black triangles. Black triangles are open gingival embrasures caused by the loss or deficiency of the interdental papilla between adjacent teeth. These spaces are a common esthetic concern and may also contribute to food impaction and periodontal problems. Thirty adult patients presenting with interdental papillary loss classified as Nordland and Tarnow Class I or II will be recruited from the outpatient clinics of the Faculty of Dentistry at King Salman International University. Eligible participants will be randomly assigned to one of three treatment groups: surgical reconstruction using the tube grafting technique, papillary augmentation using hyaluronic acid injection, or a restorative approach using the injection molding composite technique. Clinical and photographic assessments will be performed at baseline and during follow-up visits at 3 and 6 months after treatment. The primary outcomes will be the reduction in black triangle surface area and height. Secondary outcomes will include clinical periodontal parameters such as plaque index, bleeding score, probing pocket depth, and clinical attachment level. Patient satisfaction with the esthetic outcome will also be evaluated using a Visual Analog Scale (VAS). The findings of this study are expected to provide evidence regarding the comparative effectiveness of surgical and nonsurgical approaches for the management of interdental black triangles and help clinicians select the most predictable treatment modality for improving esthetic outcomes.

Detailed description

Interdental papilla deficiency resulting in the formation of "black triangles" is a frequent esthetic and functional problem in dentistry. These open gingival embrasures occur due to several factors including periodontal attachment loss, traumatic oral hygiene practices, tooth morphology, orthodontic treatment, and aging. In addition to compromising dental esthetics, black triangles may lead to food impaction, phonetic problems, and patient dissatisfaction with their smile. Several therapeutic approaches have been proposed for the management of interdental papillary loss. These approaches can generally be classified into surgical and nonsurgical techniques. Surgical methods aim to reconstruct the lost papillary tissue through soft tissue grafting procedures such as the tube grafting technique. These procedures attempt to biologically restore the interdental papilla but may involve surgical morbidity and require advanced clinical skills. Nonsurgical approaches have recently gained interest as minimally invasive alternatives. One such approach involves the use of injectable fillers such as hyaluronic acid to augment the volume of the interdental papilla. Hyaluronic acid is widely used in aesthetic medicine due to its biocompatibility and ability to promote tissue hydration and volumization. Another nonsurgical strategy is the restorative modification of tooth contours using the injection molding composite technique, which alters the shape of the proximal tooth surfaces to reduce the appearance of the gingival embrasure. Despite the availability of these different treatment options, there is limited evidence directly comparing surgical and nonsurgical approaches for the management of interdental black triangles. Therefore, the present study aims to evaluate the efficacy of these treatment modalities in a randomized clinical trial design. Thirty patients presenting with interdental papilla deficiency will be recruited from the outpatient clinic of the Faculty of Dentistry at King Salman International University. Eligible participants will be adults aged 18 to 50 years with Nordland and Tarnow Class I or II papillary loss and adequate interdental bone support (≤5 mm distance from the contact point to the alveolar crest). Participants with systemic diseases affecting wound healing, active periodontal disease, periapical pathology, pregnancy or lactation, parafunctional habits, or smoking history will be excluded. After baseline assessment, participants will be randomly allocated into three equal groups: Group I: Surgical reconstruction of the interdental papilla using the tube grafting technique. Group II: Papillary augmentation using hyaluronic acid injection. Group III: Restorative treatment using the injection molding composite technique. Baseline clinical examination will include plaque index, bleeding index, probing pocket depth, and clinical attachment level. Standardized intraoral photographs will be obtained using a digital camera under controlled conditions. Image analysis software will be used to measure the surface area and height of the black triangle. Follow-up assessments will be conducted at 3 months and 6 months after treatment. At each follow-up visit, clinical periodontal parameters and photographic measurements will be repeated. Patient satisfaction with the esthetic outcome will be evaluated using a Visual Analog Scale. The primary outcomes of this study are the changes in black triangle surface area and height over time. Secondary outcomes include periodontal clinical parameters and patient-reported esthetic satisfaction. The results of this randomized clinical trial are expected to provide clinically relevant evidence regarding the effectiveness and stability of surgical and nonsurgical techniques for the management of interdental black triangles, contributing to evidence-based decision-making in esthetic dental practice.

Interventions

PROCEDURETube Grafting Technique for Papilla Reconstruction

A surgical procedure used to reconstruct the interdental papilla for management of black triangles. Under local anesthesia, the recipient papillary area is prepared and a connective tissue graft is harvested and shaped using the tube grafting technique. The graft is inserted into the interdental area and stabilized to increase papillary volume and promote soft-tissue regeneration. The aim is to biologically reconstruct the lost papilla and reduce the gingival embrasure space.

DRUGHyaluronic Acid (HA)

A minimally invasive papillary augmentation procedure using injectable cross-linked hyaluronic acid gel. A controlled volume of hyaluronic acid (\<0.2 ml) is injected directly into the interdental papilla using a fine needle to increase tissue volume and improve papillary contour. The treatment aims to reduce the appearance of black triangles by enhancing soft-tissue fullness in the interdental region.

PROCEDUREInjection Molding Composite Technique

A restorative approach used to reduce the appearance of black triangles by modifying proximal tooth contours. A matrix system is used to guide the restoration, and a bonding agent is applied followed by injection of heated flowable composite resin. The composite is shaped to alter the emergence profile and reduce the gingival embrasure space, thereby improving interdental papilla support and esthetics.

Sponsors

Ain Shams University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Masking description

Outcome assessment will be performed by an independent examiner who is blinded to the treatment allocation. The examiner responsible for measuring the black triangle dimensions and recording clinical parameters will not be involved in delivering the interventions and will remain unaware of which treatment each participant received. Standardized intraoral photographs will be coded and analyzed without identifiers indicating the assigned treatment group to maintain assessor blinding.

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
No

Inclusion criteria

* Adults aged 18 to 50 years. Presence of interdental black triangle classified as Nordland and Tarnow Class I or Class II. Radiographic evidence of adequate interdental bone support, defined as ≤5 mm distance from the contact point to the alveolar crest. Systemically healthy individuals with no medical conditions affecting wound healing. Patients willing to participate in the study and attend follow-up visits at 3 and 6 months.

Exclusion criteria

* Patients with systemic diseases that may impair wound healing. Presence of teeth with acute periapical pathology. Presence of periodontal pockets or active periodontal disease. Pregnant or lactating women. Patients with parafunctional habits (e.g., bruxism). Smokers, alcoholics, or drug abusers.

Design outcomes

Primary

MeasureTime frameDescription
Reduction in Black Triangle Surface AreaBaseline, 3 months, and 6 months after treatment.The primary outcome will be the quantitative change in the surface area of the interdental black triangle. Measurements will be obtained from standardized intraoral photographs and analyzed using digital image analysis software. Surface area will be calculated in square millimeters (mm²). The outcomes will be compared between treatment groups to evaluate the effectiveness of the interventions in reducing interdental papillary deficiency.

Secondary

MeasureTime frameDescription
Plaque IndexBaseline, 3 months, and 6 months after treatment.Plaque accumulation around the treated teeth will be assessed using a periodontal probe and recorded according to a standardized plaque index scoring system. This measure will be used to evaluate oral hygiene status and its potential influence on treatment outcomes.
Bleeding on ProbingBaseline, 3 months, and 6 months after treatment.Bleeding on probing will be recorded during periodontal examination to evaluate gingival inflammation around the treated sites. The presence or absence of bleeding after gentle probing will be documented as an indicator of periodontal health.

Countries

Egypt

Contacts

CONTACTFatma E.A. Hassanein, PHD
fatma.hassanein@ksiu.edu.eg+201000093885
PRINCIPAL_INVESTIGATORFatma E.A. Fatma E.A., PHD

Assistant Professor Of Oral Medicine, Periodontology, Oral Diagnosis

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 24, 2026