An interventional study of Advanced Platelet-Rich Fibrin Plus (A-PRF+) Revascularization Procedure in Necrotic Immature Permanent Teeth, Regenerative Endodontic Treatment and Pulp Regeneration, sponsored by University of Zagreb. Completed at 1 site in Croatia. Open to participants aged 8 Years to 18 Years. Per ClinicalTrials.gov, last updated 2025-07-30.
Sponsored by University of Zagreb · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to evaluate the effectiveness of an advanced platelet-rich fibrin plus (A-PRF+) revascularization procedure to promote healing and root development in necrotic immature permanent single-rooted teeth in children and adolescents aged 8 to 18 years.
The main questions it aims to answer are:
Participants will:
This study will help determine whether A-PRF+ is a safe and effective alternative to conventional apexification for regenerating necrotic immature teeth in young patients.
This study is a prospective interventional clinical trial evaluating an advanced platelet-rich fibrin plus (A-PRF+) revascularization protocol compared to a historical control group treated with traditional calcium hydroxide apexification for necrotic immature permanent single-rooted teeth in children and adolescents aged 8 to 18 years.
The main goal is to assess the regenerative effectiveness of the A-PRF+ protocol in promoting root development, including root lengthening, dentinal wall thickening, and apical closure, compared to conventional apexification. Secondary objectives include evaluating pulp vitality restoration and monitoring clinical outcomes such as symptom resolution, tooth survival, and adverse effects like tooth discoloration.
Participants in the experimental group were prospectively enrolled and received treatment involving minimal mechanical instrumentation, canal disinfection with sodium hypochlorite, intracanal calcium hydroxide medicament, followed by triple antibiotic paste. At the final appointment, autologous A-PRF+ was prepared from peripheral blood and applied as an intracanal scaffold extending into the coronal cavity, sealed permanently with glass ionomer cement.
The control group consists of patients previously treated at the same institution with calcium hydroxide apexification. Their clinical and radiographic records were retrospectively reviewed for comparison. Apexification was not performed as part of this study.
Clinical and radiographic follow-ups were conducted at 1, 3, 6, 9, and 12 months, including pulp vitality testing with cold, electric, and laser Doppler flowmetry methods, along with standardized periapical radiographs to measure root length, dentinal wall thickness, and apical diameter. Restoration quality was assessed using modified USPHS criteria.
This study aims to determine if the A-PRF+ protocol provides a safe and effective regenerative alternative to traditional apexification for treating necrotic immature teeth, potentially enhancing long-term tooth preservation in pediatric patients.
University of Zagreb is the lead sponsor of 67 studies on the registry; 13 are open to participants now.
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Exclusion Criteria:
Participants receive the advanced platelet-rich fibrin plus (A-PRF+) revascularization protocol. This involves minimal mechanical instrumentation, canal disinfection with sodium hypochlorite, intracanal medicaments including calcium hydroxide and triple antibiotic paste, followed by placement of autologous A-PRF+ scaffold extending into the coronal cavity. The cavity is then permanently sealed with glass ionomer cement.
Procedure: Advanced Platelet-Rich Fibrin Plus (A-PRF+) Revascularization Procedure
The intervention consists of the advanced platelet-rich fibrin plus (A-PRF+) revascularization protocol. It includes minimal mechanical instrumentation of the root canal, disinfection using sodium hypochlorite irrigation, and intracanal medicaments-initially calcium hydroxide followed by triple antibiotic paste. Peripheral venous blood was drawn from each participant into anticoagulant-free sterile tubes. The blood was immediately centrifuged at 1300 rpm for 8 minutes to obtain the A-PRF+ clot, which was then used as the scaffold material, extending through the root canal into the coronal cavity. The cavity was permanently sealed with glass ionomer cement. This protocol aims to promote regenerative healing and continued root development in necrotic immature permanent teeth.
Also known as: Advanced platelet-rich fibrin, A-PRF+ revascularization, Platelet-rich fibrin scaffold, Regenerative endodontic procedure with PRF
Root Lengthening
Root lengthening was assessed by measuring the linear distance from the cementoenamel junction (CEJ) to the radiographic apex on standardized periapical radiographs. Radiographs were obtained using a film holder to ensure consistent angulation and minimize distortion. Measurements were performed using diagnostic software with a precision of 0.1 mm by two independent blinded examiners. The change from baseline to follow-up measurements over the 12-month period was calculated to quantify root lengthening.
Time frame: From enrollment through 12 months post-treatment
Dentinal Wall Thickening
Dentinal wall thickening was evaluated by measuring the increase in dentinal wall width at the coronal two-thirds of the root on standardized periapical radiographs. Radiographs were obtained using a film holder to ensure reproducible angulation and reduce distortion. Two blinded examiners independently performed measurements using diagnostic software with an accuracy of 0.1 mm. The difference between baseline and follow-up measurements over 12 months quantified dentinal wall thickening.
Time frame: From enrollment through 12 months post-treatment
Apical Closure
Apical closure was assessed by measuring the reduction in apical diameter on standardized periapical radiographs. Radiographs were consistently acquired using a film holder to minimize angulation differences and distortion. Two independent blinded examiners used diagnostic software with 0.1 mm precision to measure the distance across the apical foramen. Changes from baseline to follow-up at 12 months were used to quantify apical closure.
Time frame: From enrollment through 12 months post-treatment
Pulp Vitality Responses
Pulp vitality was assessed at each follow-up visit using cold testing and electric pulp testing on the treated tooth and contralateral control tooth. Laser Doppler flowmetry was performed once per patient at either the 9- or 12-month recall to quantitatively measure pulpal blood flow, indicating revascularization. All tests were performed by clinicians blinded to treatment allocation, with responses recorded as positive or negative.
Time frame: From enrollment through 12 months post-treatment
Presence of Periapical Pathology
Presence or absence of periapical lesions was evaluated on standardized periapical radiographs at baseline and follow-up visits. Two blinded examiners independently assessed images for periapical pathology. Changes in lesion presence were recorded throughout the 12-month follow-up.
Time frame: From enrollment through 12 months post-treatment
Tooth Survival
Tooth survival was defined as retention of the treated tooth throughout the 12-month follow-up period. Any tooth loss or extraction was recorded as an event. Survival status was assessed during clinical recall visits.
Time frame: From enrollment through 12 months post-treatment
Clinical Evaluation of Restorations Using Modified USPHS Criteria
Clinical performance of glass ionomer cement restorations was assessed at each recall visit using Modified United States Public Health Service (USPHS) criteria. Parameters evaluated included retention, marginal discoloration, anatomic form, marginal adaptation, secondary caries, and surface texture. Each parameter was scored as Alpha (clinically excellent), Bravo (clinically acceptable), or Charlie (clinically unacceptable/failure).
Time frame: From enrollment through 12 months post-treatment
Adverse Clinical Events
Adverse clinical events including tooth discoloration, abnormal mobility, inflammation, swelling, or sinus tract formation were recorded during clinical examinations at each follow-up visit. All findings were documented in patient records.
Time frame: From enrollment through 12 months post-treatment
This study is completed, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.
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University of Zagreb