Ovate Pontic Versus Essix Provisional After Tooth Extraction and Alveolar Ridge Preservation (Pontic-Essix)

Following tooth extraction, dimensional changes of the alveolar ridge and loss of interproximal soft tissue height may compromise esthetic and prosthetic outcomes. Alveolar ridge preservation attenuates hard tissue resorption but provides limited active support for the overlying soft tissues during healing. An ovate pontic provisional restoration may provide active soft tissue support and thereby help preserve interproximal soft tissue height. To date, no randomized controlled trial has compared a fixed ovate pontic provisional restoration with a removable non-contact Essix provisional restoration in the context of alveolar ridge preservation.

This is a single-center, open-label, confirmatory, randomized controlled trial with two parallel groups and 1:1 allocation. An adaptive design with an internal pilot phase (n=20) and blinded sample size re-estimation based on the residual variance of the primary endpoint is applied, up to a predefined maximum of 40 participants.

All participants undergo minimally traumatic, flapless single non-molar tooth extraction and alveolar ridge preservation with Bio-Oss Collagen. Test group: socket sealing by a fixed, 3D-printed ovate pontic provisional restoration providing active soft tissue support. Control group: socket sealing with Mucograft Seal plus a removable Essix-type provisional restoration positioned without intentional soft tissue contact.

Follow-up visits are performed at 2 weeks, 4 weeks, and 5 months. At baseline (T0) and at 5 months, intraoral surface scans, clinical photographs, cone-beam computed tomography, and patient-reported outcomes are collected. The between-group treatment effect on the primary endpoint is estimated using ANCOVA with the 5-month value as dependent variable, treatment group as fixed factor, and the baseline value as covariate; jaw is included as an additional between-subject factor.

Inclusion criteria

• Adults aged 18 years or older
• ASA physical status I or II
• Requiring a single non-molar tooth extraction (incisor, canine, or premolar) in the maxilla or mandible, with planned tooth replacement
• Extraction site bounded by natural, periodontally stable adjacent teeth
• Intact alveolar socket upon extraction, or no more than one bony wall (facial, palatal, or lingual) presenting a dehiscence extending less than 50% of the total bony wall height
• Willingness and ability to comply with the follow-up protocol
• Ability to give informed consent, as documented by signature

Exclusion criteria

• Current smokers, or former smokers who quit less than 6 months before extraction
• Uncontrolled diabetes mellitus (HbA1c > 7.0%)
• Clinical attachment loss ≥ 2 mm at the extraction site
• Active or recent chemotherapy, or history of head and neck radiotherapy
• Current or previous bisphosphonate therapy within the past 10 years
• Immunosuppressive medication
• Active oral or systemic acute infection
• Severe hematologic disorder, hepatic or renal failure, or any clinically relevant bleeding disorder or anticoagulant medication that cannot be safely managed for the planned surgical procedure
• Pregnancy or lactation
• Known allergy or hypersensitivity to any of the study materials, including bovine-derived bone substitute, porcine-derived collagen matrix, or collagen-containing biomaterials
• Any other disease or medication that may compromise normal wound healing
• Inability to follow the study procedures (e.g., insufficient language comprehension, cognitive impairment, psychological disorder, or dementia)
• Known or suspected non-compliance
• Participation in another clinical trial that may interfere with the present study