An interventional study of Calcium Hydroxylapatite (CaHA) Injectable Filler. and Hyaluronic Acid (HA) Injectable Filler in Loss of Interdental Papillae and Black Triangles Syndrome (BTS), sponsored by King Abdulaziz University. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-03.
Sponsored by King Abdulaziz University · Not applicable, Interventional, and Treatment
This study aims to compare two injectable materials, calcium hydroxylapatite (Radiesse®) and hyaluronic acid, for treating gaps between the teeth caused by loss of gum tissue. These gaps, commonly known as "black triangles," can affect the appearance of a person's smile and may cause food to become trapped between the teeth.
Hyaluronic acid has been used to improve the appearance of these gaps, but its effects may not last for a long time. Calcium hydroxylapatite is another injectable material that may help the body produce collagen, a natural protein that supports gum tissue. This study will investigate whether calcium hydroxylapatite can provide better or longer-lasting results compared with hyaluronic acid.
The study will take place at the Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. Approximately 20 healthy adults who have two similar gaps between their front teeth will be invited to participate.
Each participant will receive both treatments. One gap will be treated with diluted calcium hydroxylapatite, while the other will be treated with hyaluronic acid. The treatment for each site will be selected randomly to ensure a fair comparison. Each site will receive one injection.
Participants will be examined before treatment and again after 3 weeks, 3 months, and 6 months to assess the results.
During these visits, photographs and clinical measurements will be taken to evaluate changes in the size of the gaps and the amount of gum tissue between the teeth. Participants will also be asked about their satisfaction with the appearance of their gums, any discomfort experienced during treatment, and whether they have noticed an improvement in their smile. Any side effects or complications will also be recorded.
The researchers will compare how well the two materials improve the appearance of the gaps and how long the improvements last.
Participation will be voluntary, and all participants will receive information about the study before signing a consent form. Their personal information will be kept confidential, and they may withdraw from the study at any time without affecting their dental care.
The main goal of this study is to identify whether diluted calcium hydroxylapatite or hyaluronic acid provides better and longer-lasting improvement in the appearance of gaps between the teeth. The findings may help dentists choose more effective, minimally invasive treatments for patients with missing gum tissue between their teeth.
King Abdulaziz University is the lead sponsor of 98 studies on the registry; 19 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 1 (14%) have results posted.
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Exclusion Criteria:
Interdental papilla deficiencies assigned to this treatment will receive a single injection of hyper-diluted calcium hydroxylapatite (Radiesse®), prepared at a 1:2 dilution ratio using saline and lidocaine. The intervention aims to improve interdental papillary fill and stimulate collagen production, potentially providing longer-lasting tissue improvement. Clinical outcomes will be evaluated at baseline, 3 weeks, 3 months, and 6 months following treatment.
Device: Calcium Hydroxylapatite (CaHA) Injectable Filler.
Interdental papilla deficiencies assigned to this treatment will receive a single injection of hyaluronic acid (HA). The intervention aims to improve interdental papillary fill by increasing soft tissue volume and reducing the appearance of black triangles. Clinical outcomes will be evaluated at baseline, 3 weeks, 3 months, and 6 months following treatment.
Device: Hyaluronic Acid (HA) Injectable Filler
Hyper-diluted calcium hydroxylapatite (Radiesse®) will be used for the treatment of Class I interdental papilla deficiencies. The material will be prepared at a 1:2 dilution ratio using saline and lidocaine, mixed through a Luer-lock syringe connection. Each randomly assigned interdental site will receive a single injection. The treatment aims to stimulate collagen production, improve interdental papillary fill, and enhance soft tissue volume and stability. Clinical outcomes will be evaluated at baseline, 3 weeks, 3 months, and 6 months after treatment. Hyaluronic acid (HA) injectable filler will be used for the treatment of Class I interdental papilla deficiencies. Each randomly assigned interdental site will receive a single injection of HA to increase soft tissue volume, improve interdental papillary fill, and reduce the appearance of black triangles. Clinical outcomes will be evaluated at baseline, 3 weeks, 3 months, and 6 months after treatment.
Hyaluronic acid (HA) injectable filler will be used for the treatment of Class I interdental papilla deficiencies. Each randomly assigned interdental site will receive a single injection of HA to increase soft tissue volume, improve interdental papillary fill, and reduce the appearance of black triangles. Clinical outcomes will be evaluated at baseline, 3 weeks, 3 months, and 6 months after treatment.
Reduction in Black Triangle Area
Change in the area of the open gingival embrasure (black triangle) following treatment, measured in square millimeters (mm²) using standardized calibrated digital clinical photographs. The reduction in black triangle area will be compared between the calcium hydroxylapatite and hyaluronic acid treatment sites to evaluate the effectiveness of papillary reconstruction.
Time frame: Baseline, 3 weeks, 3 months, and 6 months after treatment.
Change in Interdental Papilla Height
Change in interdental papilla height (mm) from baseline following treatment with hyper-diluted calcium hydroxylapatite or hyaluronic acid. Papillary height will be measured using standardized digital clinical photographs calibrated with a UNC-15 periodontal probe and analyzed using image-analysis software (ImageJ). The distance from the papilla tip to a reference line connecting the adjacent gingival margins will be measured. Changes in papillary height will be compared between the two treatment sites.
Time frame: Baseline, 3 weeks, 3 months, and 6 months after treatment.
Change in Interdental Papilla Thickness
Change in interdental papilla thickness (mm) following treatment with calcium hydroxylapatite or hyaluronic acid. Tissue thickness will be assessed using a calibrated endodontic file fitted with a silicone stopper at a standardized reference point. Changes in tissue thickness will be compared between treatment sites to estimate improvements in papillary tissue bulk.
Time frame: Baseline, 3 weeks, 3 months, and 6 months after treatment.
Patient Satisfaction With Esthetic Outcomes
Patient satisfaction with the appearance of the treated interdental papilla will be assessed using a Visual Analog Scale (VAS). Participants will evaluate their satisfaction with the esthetic improvement achieved following each treatment. Satisfaction scores will be compared between the two treatment sites.
Time frame: 3 weeks, 3 months, and 6 months after treatment.
Global Aesthetic Improvement Scale (GAIS)
Esthetic improvement will be assessed using the Global Aesthetic Improvement Scale (GAIS), a five-point scale ranging from "worse" to "very much improved." Both participants and investigators will evaluate the improvement in interdental papilla appearance compared with baseline. Scores will be compared between the two treatment sites.
Time frame: 3 weeks, 3 months, and 6 months after treatment.
Stability of Interdental Papillary Fill
The stability of interdental papillary reconstruction will be evaluated by comparing changes in papilla height and black triangle dimensions across follow-up visits. The maintenance of treatment-related improvements at 6 months will be assessed to compare the durability of calcium hydroxylapatite and hyaluronic acid injections.
Time frame: 3 weeks, 3 months, and 6 months after treatment.
Patient Satisfaction Questionnaire (PSQ-18)
Patient-reported satisfaction will be evaluated using the Patient Satisfaction Questionnaire Short Form (PSQ-18), consisting of 18 items. The questionnaire will assess satisfaction with treatment, comfort, perceived improvement, and overall treatment experience. Responses will be compared between the two treatment sites.
Time frame: 3 weeks, 3 months, and 6 months after treatment.
Adverse Events and Complications
Any adverse effects or complications associated with calcium hydroxylapatite or hyaluronic acid injections will be recorded and compared between the treatment sites. The number and nature of reported complications will be documented to evaluate the safety of both interventions.
Time frame: From the injection procedure through the 6-month follow-up period.
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Nov 2026; primary completion for Jul 2028, 20 months later.
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King Abdulaziz University