NCT07748871

Brief Summary

This randomized controlled trial compares two provisional socket-sealing concepts following single non-molar tooth extraction and alveolar ridge preservation: a fixed, tooth-supported, 3D-printed ovate pontic provisional restoration providing active soft tissue support (test) versus a removable Essix-type provisional restoration without intentional soft tissue contact combined with a porcine collagen matrix seal (control). Both groups receive alveolar ridge preservation using a deproteinized bovine bone mineral with 10% collagen. The primary endpoint is interproximal soft tissue height at 5 months, adjusted for baseline, assessed by digital superimposition of intraoral surface scans. Up to 40 participants will be enrolled at the University of Bern School of Dental Medicine.

Trial Health

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Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
40

participants targeted

Target at P25-P50 for not_applicable

Timeline
28mo left

Started Oct 2026

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 31, 2026

Completed
6 days until next milestone

First Posted

Study publicly available on registry

August 6, 2026

Completed
2 months until next milestone

Study Start

First participant enrolled

October 1, 2026

Expected
2.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

February 1, 2029

Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

February 1, 2029

Last Updated

August 6, 2026

Status Verified

July 1, 2026

Enrollment Period

2.3 years

First QC Date

July 31, 2026

Last Update Submit

July 31, 2026

Conditions

Keywords

alveolar ridge preservationovate ponticsocket sealingprovisional restorationinterproximal soft tissuepapilladigital superimpositionrandomized controlled trial

Outcome Measures

Primary Outcomes (1)

  • Interproximal soft tissue height at 5 months

    Interproximal soft tissue height at 5 months, calculated per participant as the mean of the mesial and distal measurements and expressed in millimeters. Measurements are obtained by digital superimposition of baseline and 5-month intraoral surface scans (Geomagic Control X, 3D Systems) by an independent, calibrated examiner. The between-group treatment effect is estimated using ANCOVA with the 5-month value as the dependent variable, treatment group as a fixed factor, baseline value as a covariate, and jaw as an additional between-subject factor.

    Baseline (T0) and 5 months after tooth extraction

Secondary Outcomes (15)

  • Midfacial mucosal level at 5 months

    Baseline (T0) and 5 months

  • Horizontal ridge contour at 5 months

    Baseline (T0) and 5 months

  • Mucosal thickness at 5 months

    Baseline (T0) and 5 months

  • Volumetric soft tissue at 5 months

    Baseline (T0) and 5 months

  • Alveolar hard tissue volume at 5 months

    Baseline (T0) and 5 months

  • +10 more secondary outcomes

Study Arms (2)

Fixed ovate pontic provisional

EXPERIMENTAL

Following minimally traumatic, flapless tooth extraction, the alveolar socket is grafted with Bio-Oss Collagen. Socket sealing is achieved by a fixed, 3D-printed provisional restoration incorporating an ovate pontic design that extends approximately 2 mm apical to the mucosal margin, providing active soft tissue support to maintain interproximal papilla height and facial soft tissue contour during healing. The provisional is retained by adhesive bonding or temporary cementation on the adjacent teeth. No additional collagen matrix or sutures are placed.

Device: Bio-Oss CollagenProcedure: Fixed 3D-printed ovate pontic provisional restoration

Removable Essix provisional with collagen matrix seal

ACTIVE COMPARATOR

Following minimally traumatic, flapless tooth extraction, the alveolar socket is grafted with Bio-Oss Collagen. The socket is sealed with a porcine-derived collagen matrix (Mucograft Seal) secured with four to six single interrupted sutures, without primary closure. A removable Essix-type provisional restoration with an integrated artificial tooth is delivered; the pontic is positioned above the mucosal level without intentional soft tissue contact.

Device: Bio-Oss CollagenDevice: Mucograft SealProcedure: Removable Essix provisional restoration

Interventions

Deproteinized bovine bone mineral with 10% collagen (Geistlich Pharma AG, Wolhusen, Switzerland). Used for alveolar ridge preservation by socket grafting after tooth extraction. CE-marked and used within the approved indication.

Also known as: Fixed ovate pontic provisional, Removable Essix provisional with collagen matrix seal
Fixed ovate pontic provisionalRemovable Essix provisional with collagen matrix seal

Patient-specific 3D-printed provisional restoration (PMMA or comparable clinically approved dental provisional material) incorporating an ovate pontic design. Retained by adhesive bonding or temporary cementation on the adjacent teeth. The convex, highly polished pontic extends approximately 2 mm apical to the mucosal margin and above the level of the bone graft, providing active soft tissue support.

Removable Essix provisional with collagen matrix seal

Patient-specific 3D-printed provisional restoration (PMMA or comparable clinically approved dental provisional material) incorporating an ovate pontic design. Retained by adhesive bonding or temporary cementation on the adjacent teeth. The convex, highly polished pontic extends approximately 2 mm apical to the mucosal margin and above the level of the bone graft, providing active soft tissue support.

Fixed ovate pontic provisional

Patient-specific removable thermoplastic Essix-type appliance with an integrated artificial tooth. The pontic is positioned above the mucosal level without intentional soft tissue contact. Delivered at the surgical visit after socket sealing with the collagen matrix.

Removable Essix provisional with collagen matrix seal

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • 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

You may not qualify if:

  • 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

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Bern, Department of Reconstructive Dentistry and Gerodontology

Bern, Canton of Bern, 3010, Switzerland

Location

Related Publications (2)

  • Avila-Ortiz G, Gubler M, Romero-Bustillos M, Nicholas CL, Zimmerman MB, Barwacz CA. Efficacy of Alveolar Ridge Preservation: A Randomized Controlled Trial. J Dent Res. 2020 Apr;99(4):402-409. doi: 10.1177/0022034520905660. Epub 2020 Feb 12.

    PMID: 32050833BACKGROUND
  • Couso-Queiruga E, Garaicoa-Pazmino C, Fonseca M, Chappuis V, Gonzalez-Martin O, Avila-Ortiz G. Interproximal Soft Tissue Height Changes After Unassisted Socket Healing vs Alveolar Ridge Preservation Therapy. Int J Periodontics Restorative Dent. 2024;44(5):520-533. doi: 10.11607/prd.6809.

    PMID: 37471159BACKGROUND

MeSH Terms

Conditions

Tooth LossAlveolar Bone Loss

Condition Hierarchy (Ancestors)

Periodontal DiseasesMouth DiseasesStomatognathic DiseasesTooth DiseasesBone ResorptionBone DiseasesMusculoskeletal DiseasesPeriodontal Atrophy

Study Officials

  • Nicole Schenk, Dr. med. dent.

    University of Bern, Department of Reconstructive Dentistry and Gerodontology

    PRINCIPAL INVESTIGATOR
  • Martin Schimmel, Prof. Dr. med. dent.

    University of Bern, Department of Reconstructive Dentistry and Gerodontology

    STUDY CHAIR
  • Emilio Couso-Queiruga, PD Dr. med. dent.

    University of Bern, Department of Oral Surgery and Stomatology

    STUDY DIRECTOR

Central Study Contacts

Nicole Schenk, Dr. med. dent.

CONTACT

Martin Schimmel, Prof. Dr. med. dent.

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
OUTCOMES ASSESSOR
Masking Details
The trial is open-label for participants and treating clinicians because the two provisional restorations are clinically distinguishable. The examiner performing the digital analysis of intraoral surface scans and CBCT data is independent of the clinical treatment and is blinded to group allocation; outcome data are coded before analysis.
Purpose
TREATMENT
Intervention Model
PARALLEL
Model Details: Single-center, open-label, confirmatory, randomized controlled trial with two parallel groups and 1:1 allocation. Adaptive design with an internal pilot phase (n=20) and blinded sample size re-estimation based on the residual variance of the primary endpoint, up to a predefined maximum of 40 participants.
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 31, 2026

First Posted

August 6, 2026

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

February 1, 2029

Study Completion (Estimated)

February 1, 2029

Last Updated

August 6, 2026

Record last verified: 2026-07

Data Sharing

IPD Sharing
Will not share

Individual participant data will not be publicly shared. The informed consent and data protection framework of this trial do not provide for unrestricted public sharing of coded participant-level data. Aggregated study results will be published in a peer-reviewed journal and posted in the Swiss National Clinical Trials Portal (SNCTP) and on ClinicalTrials.gov in accordance with ClinO Art. 65a.

Locations