Clinical Outcomes of Bone‐Level and Tissue‐Level Short Implants Placed in Posterior Maxilla: A Case–Control Study
Bibliographic record
Abstract
INTRODUCTION: Short implants are today a reliable, minimally invasive option for the rehabilitation of the posterior maxilla. However, maintaining marginal bone stability remains a crucial factor for long-term success, particularly in the case of short implants. The present multicenter prospective case-control study aimed to compare the clinical outcomes of bone-level and tissue-level short implants in the posterior maxilla, focusing on implant survival and peri-implant marginal bone stability over 1 year of function. METHODS: Fifty-nine patients who met specific inclusion criteria were enrolled and treated by three clinical centers with a total of 74 short implants, either bone-level (7 mm in length, placed 1 mm sub-crestally) or tissue-level (5 or 6.5 mm in length). The primary outcome was physiological bone remodeling (PBR) measured via radiographs at baseline (T0), prosthesis delivery (T1), and 12 months post-loading (T2). Statistical analysis was performed to evaluate differences in PBR between groups, with multivariate analysis assessing the influence of various patient and site-specific factors. RESULTS: The final analysis included 58 patients who were treated with a total of 71 short implants, comprising 36 tissue-level and 35 bone-level implants (one patient dropped out as he did not attend follow-up visits on time). All implants were rehabilitated with fixed, screwed prosthetics after 5 months, with no recorded complications up to 1 year of loading. Stability was similar between the two implant types at T0 and T1, with no significant differences in insertion torque and implant stability quotient (ISQ). Multivariate analysis revealed a significant positive correlation between insertion torque and ISQ at T0, as well as with bicortical engagement of the implant apex with the sinus floor. Tissue-level implants demonstrated significantly lower peri-implant bone remodeling (PBR) compared to bone-level implants at both T1 (0.11 ± 0.27 mm vs. 0.34 ± 0.35 mm, p = 0.004) and T2 (0.30 ± 0.23 mm vs. 0.55 ± 0.42 mm, p = 0.003). Multivariate analysis showed a significant positive correlation between PBR (T0-T1) and thin vertical mucosal thickness (≤ 2 mm) at T0 in both tissue-level and bone-level implants. Additionally, PBR (T1-T2) in both groups significantly correlated with the use of short prosthetic abutments (≤ 2 mm) and, only in bone-level implants, with crown emergence angles > 30°. CONCLUSION: Both tissue-level and bone-level short implants are effective options for implant-supported rehabilitation in the posterior maxilla. Tissue-level short implants offer superior marginal bone stability compared to bone-level implants placed subcrestally, suggesting their favorable use in clinical practice.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".