Effectiveness of Graftless Maxillary Sinus Floor Augmentation on Alveolar Crest Height and Implant Survival: A Review of Randomized Controlled Studies

Dental implants combined with sinus augmentation: What is the merit of bone grafting? A systematic review.

Purpose: Radiographic evaluation of the vertical presurgical ridge height (PRH) of implants, placed using the transcrestal or lateral window sinus floor elevation (SFE) technique in edentulous and partially dentate patients. The 5-year implant survival rate and the prosthetic restoration following the SFE procedure were also evaluated. Methods: Radiographs of 83 tapered implants placed in 53 patients were available for analysis. 31 implants were placed by the transcrestal and 52 were placed by the lateral window technique. In the lateral window technique 21 implants were placed simultaneously, 31 in a staged approach. The PRH, the implant survival rate after five years and the prosthetic restoration were evaluated with respect to the chosen SFE procedure. Results: The PRH was significantly higher for the transcrestal than both lateral window techniques, mean values: 8.0 ± 2.7 mm (transcrestal); 4.2 ± 2.6 mm (lateral simultaneous); 4.5 ± 2.8 mm (lateral staged). There was no significant difference of PRH between the edentulous and partially dentate patients. All loaded implants were stable, resulting in a 100% implant survival rate after 5 years. There was a small overproportion of single crown restorations in the transcrestal SFE technique group. Conclusion: This study confirms that the transcrestal technique is chosen, when a higher PRH is available. The choice of a simultaneous or staged lateral window approach is mainly dependent on the expected primary stability of the implant and not only on the PRH. SFE procedures are a safe and predictable treatment option to place implants in the vertical atrophic maxilla.

Implant therapy has become an excellent treatment modality as its inception into the modern era of dentistry. However, when patients present with advanced atrophy of the maxillary alveolar ridge, the procedure of choice to restore the anatomic bone deficiency is surgical maxillary sinus floor elevation or sinus lift. The purpose of this study was to describe the CT guided sinus lift technique and to illustrate the minimally invasive aspect of this new radiological procedure called radiological sinus lift. For this prospective study, 17 cadaver heads which met our inclusion criteria (edentulous posterior maxillary sector and bone height less than 5 mm) were analyzed using cone beam computed tomography (CBCT) and orthopantomography (OPT). CT and sinus endoscopy was used to guide each step in the procedure. The radiological sinus lift technique consists of the following four stages: Approach. A 14.5 G OstyCut needle was inserted mesial to the canine eminence, and manual drilling was performed parallel to the sinus floor. Osteotomy. An inner obturator with a blunt tip was introduced to compress bone, to push it in close proximity to the sinus membrane and finally to create an osseous window opening into the submucosal space. Lifting. The sinus lift was performed using hydrodissection with dilute iodinated contrast medium. Filling. The submucosal space was then filled with an injection of dilute collagen. Success of the radiological sinus lift procedure was defined by the presence of a dome shape visible within the maxillary alveolar recess. All cases were imaged postoperatively using OPT and maxillary CBCT. Twelve maxillary sinuses underwent the radiological sinus floor elevation procedure. A dome shape of the Schneiderian membrane was achieved in eight maxillary sinuses (66.7%). All failures (n = 4) were caused by mucosal perforation at the time of maxillary sinus osteotomy. Mean height of membrane elevation was 12.0 mm, with a mean intervention time of 45 min. This experimental study evaluates a new minimally radiological procedure for maxillary sinus floor elevation, which provides an interventional radiological alternative to the classical surgical lateral approach and achieves an equivalent success rate to that cited in the literature for the surgical approach, a low morbidity and a shorter operating time.

This retrospective study evaluated and compared the 2-year outcomes for sinus floor elevation performed via either an osteotome-mediated sinus floor elevation (OSFE) technique or a reamer-mediated sinus floor elevation (RSFE) technique. Implant survival, as well as surgical and postoperative complications, were used as measures of comparison. Patients were analyzed according to defined inclusion criteria. Orthopantography was used to assess preoperative; immediate postoperative; and 6-, 12-, and 24-month postoperative bone level changes. Implant survival and the incidence of complications, including sinus membrane perforation, were evaluated using appropriate statistical tests. From 2008 to 2010, 126 implants were placed simultaneously with sinus floor elevation in 85 patients (n = 43 women and 42 men; mean age ± standard deviation [SD] = 58.1 ± 10.2 years). The OSFE procedure (control) was used to place 65 implants in 45 patients, and the RSFE procedure (experimental) was used to place 61 implants in 40 patients. The mean maxillary residual bone height was 7.1 ± 1.6 mm. Endosinus bone gains were 5.7 ± 1.5 mm and 5.6 ± 2.3 mm for the experimental and control groups (P = .164), respectively, and the 2-year survival rates were 98.4% and 98.5%, respectively. Although no significant differences were observed between the two groups, three (6.7%) membrane perforations occurred in the OSFE group, and none occurred in the RSFE group. Other postoperative complications, including nasal bleeding, postoperative headache, and dizziness, were documented in 7 (15.6%) of 45 OSFE cases and 3 (7.5%) of 40 RSFE cases. The results presented herein indicate that comparable survival rates were achieved for implants placed in conjunction with a reamer- vs osteotome-mediated technique. Therefore, RSFE is a reliable and predictable procedure for implant placement in the posterior maxilla, with a low incidence of complications.

Gradual and safe technique for sinus floor elevation using trephines and osteotomes with stops: a cadaveric anatomic study

Objective: the present equivalence two-arm parallel randomized controlled trial aimed to compare survival and marginal bone loss (MBL) of short implants (≤6 mm) and standard implants (≥8.5 mm) associated with sinus floor elevation (SFE). Methods: adult patients with partial edentulism with occlusal stability in the sinus area and intermediate bone height were selected in this double-blind trial (patient and outcome assessment). Patients were randomly allocated into two groups: standard length implants with SFE (control) or short implants (test). Clinical and radiographic assessments were made at the time of implant placement, 6 months, and annually thereafter up to 2 years after loading. The inter-examiner agreement was analyzed using intraclass correlation coefficient (ICC). One-way ANOVA, Kaplan-Meier, and Log-rank tests were used to compare implant survival (primary outcome) and MBL (secondary outcome) (P<0.05). Results: eight short implants and six standard implants were placed (mean age of patients was 47 ±12.5 years). The implant survival rates were 87.5% for short (one 5 mm implant failed at 7 months) and 100% for standard implants with no statistically significant difference between groups (P=0.4). The mean MBL after 1 year was 0.30 ±0.62 mm for short and 0.21 ±0.36 mm for standard implants (P=0.123). The inter-examiner agreement was set in 0.831. Conclusion: survival of short implants and standard implants associated with SFE was similar after two years of clinical service. Trial registration: Registered on 27-03-2018 at ClinicalTrials.gov (NCT03479333). Funding: This study was partially funded by Capes Finance Code 001 and #88881.187933/2018-01. TPC is partially funded by National Council for Scientific and Technological Development (CNPq - Brazil). The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript.Keywords: bone resorption; dental implants; sinus floor augmentation; survival.

The aim of this article was to describe our experience in the field of preoperative ear, nose and throat (ENT) assessment in each candidate for (maxillary) sinus floor elevation (SFE) after the introduction of a systematic protocol. The protocol evaluates the sinus compliance by means of ENT preliminary examination with nasal fiberoptic endoscopy to identify all of the situations that may predispose to post-lifting complications, i.e. potentially irreversible (PIECs) and presumably reversible (PRECs) ENT contraindications to SFE, and to evaluate its impact on SFE success. Patient candidates for SFE were carefully assessed by means of case-history collection, complete ENT evaluation with nasal fiberoptic endoscopy and imaging to detect PIECs, PRECs, or no ENT contraindications for SFE. In case of PRECs, SFE was postponed until complete clinical recovery. Impact of preoperative ENT assessment on SFE outcome was assessed by means of post-lifting telephonic interview and ENT evaluation. PRECs were detected and resolved before SFE was performed in 38.2% of our 34 patients; no intra- or post-lifting complications occurred in the patients with no ENT contraindications or PRECs. The results of the study suggest that a careful multi-tasking preoperative management, including an ENT assessment with fiberoptic endoscopy and a radiological evaluation extended to the ostio-meatal complex, is very useful in candidates for SFE.

A new technique for the transcrestal sinus floor elevation and alveolar ridge augmentation with press-fit bone cylinders: A technical note

Maxillary sinus floor augmentation (MSFA) is widely used and considered a predictable procedure for implant placement. However, the influence of MSFA on implant survival and marginal bone loss (MBL) is still inconclusive. The purpose of this retrospective observational study is to evaluate the long-term genuine influence of MSFA on the survival and MBL of implants by comparing those with and without MSFA only in maxillary molars within the same patients. Thirty-eight patients (28 male and 10 female), with a total of 119 implants, received implants with and without MSFA, and were followed up for 5.8 to 22 years. Patient- and implant-related factors were assessed with a frailty model for implant survival and with generalized estimation equations (GEE) for MBL around the implant. No variables showed a statistical significance for implant failure in the frailty model. In GEE analysis for MBL, MSFA did not show any statistical significance. In conclusion, MSFA demonstrated no significant influence on implant failure and MBL in posterior maxilla in this study.

The Need for Large Clinical Studies in Perioperative Medicine

Survival rates of implants placed in transalveolar sinus floor augmentation sites are comparable with those placed in non-augmented sites. Flapless implant surgery can minimize postoperative morbidity, alveolar bone resorption and crestal bone loss. The use of cone beam computerized tomography (CBCT) provides 3D presentations with reduced dose exposure. To evaluate a flapless, CBCT-guided transalveolar sinus floor elevation technique with simultaneous implant installation. Fourteen consecutive patients in need of maxillary sinus floor augmentation were enrolled in this study. Preoperative CBCT with a titanium screwpost as an indicator at the intended implant position was used to visually guide the flapless surgical procedure. Twenty one implants all with a length of 10 mm and a diameter of 4.1 and 4.8 mm were inserted and followed clinically and with CBCT for 3, 6 and 12 months postoperatively. Intraoral radiographs were taken for comparison. All patients were provided with permanent prosthetic constructions 8-12 weeks after implant surgery. Ten (47.6%) implants were inserted in residual bone of 2.6-4.9 mm and 11 (52.3%) implants were inserted in residual bone of 5-8.9 mm. No implants were lost after surgery and follow-up. There was no marginal bone loss during the follow-up verified by CBCT. The implants penetrated on average 4.4 mm (SD 2.1 mm) into the sinus cavity and the mean bone gain was 3 mm (SD 2.1 mm). Flapless transalveolar sinus lift procedures visually guided by preoperative CBCT can successfully be used to enable placement, successful healing and loading of one to three implants in residual bone height of 2.6-8.9 mm. There was no marginal bone loss during the 3-12 months follow-up.

Background/Objectives: Vertical ridge augmentation remains a critical challenge in implant dentistry for addressing inadequate alveolar bone height. The inlay technique, or sandwich osteotomy, has gained attention for its potential to improve graft vascularization and predictability. This systematic review aimed to evaluate the clinical outcomes of the inlay technique. Methods: A systematic search was conducted in Cochrane Library and Medline databases for studies published from 2015 to 2025 to capture the most recent studies and advancements specifically focusing on the inlay technique. Inclusion criteria encompassed observational and interventional studies, including randomized controlled trials (RCTs) and cohort and case series with a focus on outcomes related to the inlay technique. Key outcomes were extracted and analyzed, including implant survival rates, MBL, vertical bone gain, and surgical complications. Results: Eleven studies involving 352 patients and more than 612 implants were included, with a mean follow-up of 2.27 ± 2.69 years (range: 4 months to 8 years). The implant survival rates ranged from 84.5% to 100%. Mean vertical bone gain varied from 2.69 to 4.4 mm. Complications were fewer with the inlay technique compared to onlay and other grafting methods, with significantly reduced graft-related failures and soft tissue issues. Conclusions: The inlay technique shows good vertical bone augmentation with high implant survival rates and fewer complications compared to other reconstructive techniques. Longer follow-up studies are needed to support its value in managing vertically deficient ridges. Moreover, further studies with extended follow-up are required to evaluate long-term marginal bone loss.

To compare clinical and radiographic outcomes between transcrestal sinus floor elevation (TSFE) and lateral sinus floor elevation (LSFE) approaches of simultaneous implant placement in atrophic maxilla. Patients with a residual bone height (RBH) ≤6mm were enrolled and randomly assigned to TSFE and LSFE groups. Patients in both groups simultaneously underwent sinus floor elevation with bovine-derived xenograft and implant placement. Clinical and radiographic results were evaluated immediately after surgery and after 6, 12, 18, and 24months. The endo-sinus bone gain (ESBG), apical implant bone height (ABH), endo-sinus bone-implant contact rate (EBICR), and crestal bone level (CBL) were assessed using panoramic radiographs. Forty-one implants (TSFE: 21, LSFE: 20) were placed in cases with a mean RBH of 3.77±1.16mm. All implants obtained clinical success and satisfactory ESBG at 24months. No significant differences were found in ESBG and ABH between two groups immediately after surgery, but LSFE group showed significantly higher values than TSFE group thereafter. Grafts in TSFE group reached stability 6months earlier than that in LSFE group. In both groups, EBICR was almost 100%, and CBL showed no detectable changes. LSFE can achieve higher ESBG 2years after surgery. Otherwise, TSFE could be an alternative to LSFE, when the access for lateral window preparation is limited. Both approaches were highly predictable for RBH≤6mm during 24-month observation period for the implants placed simultaneously.

Maxillary sinus floor elevation is an option in cases where bone volume in the maxillary molar region is clearly insufficient to allow implant therapy. However, few studies have reported long-term observation of change in bone volume in the same case over a period of 10 or more years. This report describes a case of implant placement following maxillary sinus floor elevation using iliac bone with long-term monitoring of changes in peri-implant bone volume. The patient was a 58-year-old man who visited our clinic in April 2008 with the chief complaint of chewing problems due to missing teeth. The maxillary sinus floor bone had thinned on both sides, and bilateral maxillary sinus floor elevation using an iliac bone graft was therefore planned. In September 2008, trabecular bone containing bone marrow was harvested from the left side of the ilium, and bilateral maxillary sinus floor elevation was carried out with the patient under general anesthesia. After bone healing for approximately 6 months, a total of eight implants were placed in the maxilla under intravenous sedation in March and April 2009. A telescopic-retained implant-supported fixed bridge was attached as the final superstructure in April 2010. Regarding change in bone volume in the elevated maxillary sinus floor, a reduction in bone height was seen during the period between maxillary sinus floor elevation to implant placement. Following implant placement, however, there was no obvious decrease in bone volume, which has remained stable for 10 years following fitting of the superstructure. Maxillary sinus floor elevation with autologous iliac bone graft has thus shown long-term stability in bone volume over more than 10 years following the procedure. Rigorous follow-up of change in bone volume at the engraftment site is still needed, however.

Long-term survival rate of implants placed in conjunction with 246 sinus floor elevation procedures: Results of a 15-year retrospective study