Dental Implant Bone Loss
Conditions
Keywords
Dental implant, crestal bone loss, microthreads, implant-abutment connection
Brief summary
This randomized controlled trial aimed to assess the effect of the implant neck design (microthreaded vs. non-microthreaded) as well as the type of abutment connection (internal conical vs. external flat-to-flat) on long-term crestal bone remodelling and peri-implant health. Four implants used for a bar-retained maxillary overdenture, were followed over a period of at least 6 years. Twenty-five patients were treated with a bar-retained maxillary overdenture. Four different implants were placed, with respectively: internal connection and microthreads on the implant neck (I MT); internal connection, without microthreads (I NMT); external connection, with microthreads (E MT); and external connection, without microthreads (E NMT). Other design features, s.a. diameter, surface topography, extent of platform switch as well as the surgical and prosthetic treatment protocol were identical. Radiographic crestal bone loss (CBL), plaque score (PS), bleeding on probing (Bop) and probing pocket depth (PPD) were determined at 1 and 6 years after implant placement.
Interventions
DEVICEImplant placement
Each patient received 4 implants to support a bar supported overdenture. One implant is commercially available, 3 implants were experimentally made by the manufacturer for this study. The implants were similar in macro-desing, surface and platform shift but differ in microthread design and implant-abutment connection.
Sponsors
University Ghent
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Intervention model description
Split-mouth study
Eligibility
Sex/Gender
ALL
Age
21 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Edentulous in the maxilla and sufficient bone to harvest four 4 x 9 mm implant
Exclusion criteria
* Head -and neck radiation * Bisphosphonate intake * Limited prosthetic height
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Crestal bone loss | The measurements were performed at 1 and 6 years | Radiographic measurement of crestal bone loss |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Plaque | The measurements were performed at 1 and 6 years | Plaque was measured at 4 sites on each implant |
| Probing pocket depth | The measurements were performed at 1 and 6 years | — |
| Bleeding on probing | The measurements were performed at 1 and 6 years | — |
Countries
Belgium
Outcome results
None listed