Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
The primary aim of this randomized clinical trial is to evaluate the influence of subcrestal implant placement depth (-2 mm vs -4 mm) on peri-implant marginal bone level changes, including marginal bone loss and bone remodeling. Secondary outcomes include implant success, peri-implant probing depth (PPD), and bleeding on probing (BoP).
Partially edentulous patients requiring fixed implant-supported prosthetic rehabilitation with two implants in posterior maxillary or mandibular regions will be included. Implants will be placed subcrestally at either -2 mm or -4 mm from the bone crest, following a submerged healing protocol. Allocation to insertion depth will be randomized. Marginal bone level changes will be assessed using standardized periapical radiographs at second-stage surgery, prosthesis placement, and at 1, 3, 6, and 12 months after functional loading. PPD and BoP will be recorded at the same time points.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| -2 mm subcrestal implant placement with 2-mm slim transmucosal abutments | Experimental | Participants in this group will receive implants placed 2 mm below the level of the alveolar bone crest. Implants will share the same design, surface characteristics, and prosthetic connection, including platform switching. Slim transmucosal abutments with a height of 2-mm will be placed according to the subcrestal depth to ensure an adequate transmucosal profile and a stable relationship between the implant, peri-implant soft tissues, and the prosthetic restoration |
|
| -2 mm subcrestal implant placement with 3-mm slim transmucosal abutments | Experimental | Participants in this group will receive implants placed 2 mm below the level of the alveolar bone crest. Implants will share the same design, surface characteristics, and prosthetic connection, including platform switching. Slim transmucosal abutments with a height of 3-mm will be placed according to the subcrestal depth to ensure an adequate transmucosal profile and a stable relationship between the implant, peri-implant soft tissues, and the prosthetic restoration. |
|
| -4 mm subcrestal implant placement with 4-mm slim transmucosal abutments | Experimental | Participants in this group will receive implants placed 4 mm below the level of the alveolar bone crest. Implants will share the same design, surface characteristics, and prosthetic connection, including platform switching. Slim transmucosal abutments with a height of 4-mm will be placed according to the subcrestal depth to ensure an adequate transmucosal profile and a stable relationship between the implant, peri-implant soft tissues, and the prosthetic restoration. |
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Subcrestal Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol | Procedure | Participants will receive bone-level dental implants placed subcrestally at either -2 mm or -4 mm below the bone crest in healed posterior sites of the maxilla or mandible, according to randomization. Implant placement will follow the manufacturer's drilling protocol, achieving a final insertion torque of at least 35 Ncm. A transmucosal abutment will be connected at the time of surgery, with height selected based on implant placement depth (2-3 mm for -2 mm placement and 4-5 mm for -4 mm placement). The abutment will be tightened to a final torque of at least 30 Ncm following a one abutment-one time protocol. |
| Measure | Description | Time Frame |
|---|---|---|
| Changes in peri-implant marginal bone level (mm) | Parallelized periapical radiographs will be obtained and a calibrated digital tool will be used to determine the vertical distance from the implant-abutment junction to the most coronal bone-to-implant contact on the mesial and distal sides. Unit of measure: Milimeters (mm) | From abutment placement (baseline time [TB]), 1 month post (T1), and at 3 (T3) (prosthetic loading) , 6 (T6), and 12 (T12) months after definitive prosthesis placement. |
| Measure | Description | Time Frame |
|---|---|---|
| Peri-implant probing depth (mm) | Peri-implant soft tissue condition will be assessed by recording PPD using a periodontal probe at six surfaces per implant (mesiobuccal, midbuccal, distobuccal, and the corresponding lingual/palatal sites) to calculate the mean of every implant. Unit of measure: Milimeters (mm) | 1 month post-op (T1), and at months 3 (T3) (prosthetic loading) , 6 (T6), and 12 (T12) after definitive prosthesis placement. |
| Measure | Description | Time Frame |
|---|---|---|
| Baseline characteristics | Baseline variables will be collected for descriptive purposes and will not be combined into a single outcome measure. These include: age (years); sex (male/female); smoking habit (non-smoker or ā¤10 cigarettes/day); brushing frequency (0, 1-2, or 3 times/day); edentulism type (interdental or free end); periodontal phenotype (thin or thick); antagonist type (natural teeth, tooth-supported bridge, implant-supported prosthesis, or removable prosthesis); cause of tooth loss (caries, periodontitis, or fracture); implant location (arch and quadrant); and soft tissue thickness (mm). |
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Role | Phone | Extension | |
|---|---|---|---|---|
| Juan Carlos Bernabeu Mira, DDS, MSc, PhD | Contact | +34 697348312 | juan.c.bernabeu@uv.es |
| Name | Affiliation | Role |
|---|---|---|
| Ana VerĆ³nica Blanco Besteiro, DDS, MSc and PhD candidate | University of Valencia | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| University of Valencia | Valencia | Valencia | 46003 | Spain |
The plan to share individual participant data (IPD) has not yet been determined.
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
|
| -4 mm subcrestal implant placement with 5-mm slim transmucosal abutments | Experimental | Participants in this group will receive implants placed 4 mm below the level of the alveolar bone crest. Implants will share the same design, surface characteristics, and prosthetic connection, including platform switching. Slim transmucosal abutments with a height of 5-mm will be placed according to the subcrestal depth to ensure an adequate transmucosal profile and a stable relationship between the implant, peri-implant soft tissues, and the prosthetic restoration. |
|
|
| Bleeding on probing (presence/absence) | Bleeding on probing will be measured by gently passing a periodontal probe (using ~20-25g of force) to the base of the sulcus/pocket of the prosthesis at six surfaces per implant (mesiobuccal, midbuccal, distobuccal, and the corresponding lingual/palatal sites), then waiting 30 seconds to observe bleeding. It will be recorded as a dichotomous score (yes/no). Unit of measure: Percentage of sites showing bleeding per implant. | 1 month post-op (T1), and at months 3 (T3) (prosthetic loading) , 6 (T6), and 12 (T12) after definitive prosthesis placement. |
| Implant success | Assessment of the implants will be performed by categorizing them into: success (optimal health), satisfactory survival, compromised survival, or failure. | From the time of surgery through the end of the 12-month follow-up period after definitive prosthesis placement. |
| At enrollment time. |