To evaluate the clinical outcomes of modified crestal and lateral approaches in maxillary sinus lift. Fifty patients with single missing posterior maxillary teeth and severe bone deficiency (residual bone height < 5 mm) requiring implant placement were selected from a tertiary hospital's dental department between January and December 2023. Patients were randomly assigned to the modified crestal sinus lift group (experimental group) or the lateral window sinus lift group (control group). Behavioural cognition was assessed using the Hospital Anxiety and Depression Scale (HADS), postoperative pain was quantified using the Visual Analog Scale (VAS). Bone gain was evaluated by Gained Bone Height (GBH), and implant success rate and complication incidence were recorded. The t-test was used for intergroup comparisons, and categorical data were analysed using the chi-square test. Statistical significance was set at p < 0.05. Significant differences were observed between the experimental and control groups in pre- and postoperative behavioural cognition, surgical time, and VAS pain scores (p < 0.05). No significant differences were found in bone gain, implant success rate, or complication incidence. The bone augmentation outcomes of the two surgical techniques were essentially comparable. However, the modified crestal approach demonstrated advantages over the lateral window technique in terms of minimal trauma, improved patient behavioural cognition, and reduced postoperative pain. These findings suggest that optimising minimally invasive sinus lift techniques may enhance clinical applications, particularly with patient-centred considerations.

Perforation is the most common complication of sinus floor elevation (SFE) surgery, and is closely associated with the thickness of the maxillary sinus membrane. This study aimed to evaluate the relationship between maxillary sinus membrane thickness and anatomical variations in the osteomeatal complex (OMC). Cone beam computed tomography scans were retrospectively analyzed, encompassing 1957 sinuses. Mucosal thickness (MT) and mucosal appearance (MA) were classified as normal, flat thickening, polypoid thickening, or ostium obstruction. Ostium width (OW), infundibulum length (IL), and ethmoidal bulla diameter (EBD) were measured. The presence of Haller cells (HC), concha bullosa (CB), and superior attachment of the uncinate process (UPSA) was recorded. Kruskal-Wallis, Mann-Whitney U, Chi-square, and GEE models were used. Mucosal thickening was observed in 54% of the sinuses, with flat thickening (23.5%) being the most prevalent pattern. A significant association was found between ostium obstruction and MT greater than 10 mm. MT, IL, OW, and EBD values were significantly higher in men than in women. Significant correlations were also identified between MT and IL, OW, EBD, and HC. No significant relationship was found between CB and MT. However, UPSA types 3, 4, and 6 were significantly associated with polypoid thickening and ostium obstruction. The findings demonstrate that anatomical variations in the OMC influence maxillary sinus membrane thickness. A comprehensive evaluation of these variations should be performed before planning for SFE procedures. Dentists should be proficient in identifying and assessing the osteomeatal region during routine radiographic examinations to prevent potential complications.

Concentrated growth factor combined with sticky bone is associated with enhanced bone regeneration in patients with diabetes undergoing maxillary sinus floor elevation

Maxillary sinus floor elevation is a well-established procedure for increasing bone volume in the posterior maxilla, yet the regenerative outcome depends strongly on the choice of grafting material. This clinical study compared a high-temperature sintered xenograft (Bio-Oss®) and a low-temperature processed xenograft (Ti-Oss®) with regard to their regenerative and immunological profiles. Eight patients underwent split-mouth sinus augmentation with both materials, and biopsies were retrieved at 6 months after implant placement. Histological, histomorphometrical, and immunohistochemical analyses were performed to assess bone formation, material resorption, and tissue compatibility. Immunohistochemistry was applied to evaluate the local immune response, focusing on macrophage polarization and multinucleated giant cell activity. Quantitative histomorphometry determined the relative areas of newly formed bone, residual graft material, and connective tissue. Histopathological and histomorphometrical analyses demonstrated comparable levels of new bone formation in both groups, confirming reliable osteoconduction. Immunohistochemical evaluation revealed tartrate-resistant acid phosphatase isoform 5a (TRAP5A) expression in multinucleated giant cells adherent to both materials. Interestingly, Bio-Oss® induced a higher proportion of anti-inflammatory (CD163+) macrophages, whereas Ti-Oss® triggered a significantly greater number of pro-inflammatory multinucleated giant cells (CD11c+). These findings indicate that although both xenogeneic substitutes (Bio-Oss® and Ti-Oss®) achieve bone regeneration, they elicit distinct immune responses, which may influence long-term remodeling and graft integration. Consideration of osteoimmunological properties is therefore essential when selecting biomaterials for clinical sinus augmentation.

Background/Objectives: Limited residual bone height in the atrophic posterior maxilla complicates implant placement. Transcrestal sinus elevation can be used to correct bone shrinkage after sinus pneumatization or crestal bone loss. This study evaluated a minimally invasive, one-stage transcrestal sinus lift using a double-layer crosslinked collagen scaffold (MCCS) with autogenous bone from the implant osteotomy site in patients with RBH ≤ 6 mm. Methods: In this prospective series, 11 patients (48–64 years, mean RBH 4.75 mm, SD 0.95 mm) underwent one-stage transcrestal sinus floor elevation with simultaneous implants. After osteotomy, autogenous bone chips collected during drilling were compacted into the site, and two layers of MCCS were placed under the elevated Schneiderian membrane. Buccal and palatal bone heights were measured on CBCT before and after surgery to assess vertical bone gain (ΔRBH). Results: All implants achieved stable osseointegration. Mean ΔRBH was approximately 3.1 ± 0.9 mm (combined buccal–palatal). No postoperative complications occurred. Two small Schneiderian membrane perforations were sealed intraoperatively by MCCS placement, with uneventful healing. Follow-up imaging showed maintenance of the augmented bone around the implants. Conclusions: This double-layer MCCS plus autogenous bone approach is a safe, effective, and minimally invasive transcrestal sinus lift for atrophic maxillae. It yielded crestal bone gains even with minimal initial RBH, leveraging the palatal sinus wall’s osteogenic potential and the implant’s tent-pole effect. The MCCS scaffold maintained space for bone formation and enabled immediate sealing of any membrane perforations. This one-stage protocol is viable for implant placement in low-RBH sites.

Objective: To describe the clinical effectiveness and biological mechanisms of recombinant human bone morphogenetic protein-2 (rhBMP-2) in maxillary bone regeneration, emphasizing its role in replacing autogenous bone grafts in severe resorption cases and expanding prosthetic rehabilitation options. Methodology: A narrative review of the literature was conducted through searches of PubMed, LILACS, and institutional repositories focusing on clinical applications of rhBMP-2 in bone reconstruction relevant to dental implant rehabilitation. Publications addressing sinus augmentation, ridge augmentation, and clinical reports were included to provide a comprehensive overview. Additionally, case evidence from clinical portals was considered to illustrate real-world clinical protocols. Results: The evidence indicates that rhBMP-2 enhances osteoinduction by stimulating mesenchymal cell differentiation into osteoblasts, promoting new bone formation. Clinical use in alveolar ridge preservation, augmentation before implant placement, and sinus floor elevation has shown satisfactory bone regeneration that facilitates prosthetic rehabilitation without the need for extraoral grafting, reducing morbidity and treatment time. Conclusion: rhBMP-2 is a viable biological alternative to autogenous bone grafts in maxillary bone regeneration procedures, offering predictable outcomes in complex rehabilitations. However, careful case selection, standardized protocols, and further high-quality clinical trials are necessary to establish long-term safety and optimal use.

Aim. This study aimed to evaluate the immunogenicity of the Nano Graft biomaterial in biopsies obtained from the maxillary sinus augmentation zone using morphological and immunohistochemical assessment of the cellular response. Materials and methods. The study included 22 patients with partial posterior edentulism who underwent open maxillary sinus floor elevation using the Nano Graft biomaterial. Biopsy samples collected at the time of implant placement were fixed, decalcified, and processed for histological and immunohistochemical analysis with the following markers: CD8 (cytotoxic T lymphocytes), FOXP3 (regulatory T cells), CD68 (macrophages/osteoclasts), CD163 (M2 macrophages), SATB2 (osteogenic cells), and CD34 (endothelial cells). Inflammatory activity was assessed using a semi-quantitative scale. Results. Histological examination revealed fibrous connective tissue containing fibroblasts, microvascular structures, and signs of osteon formation and bone remodeling. Immunohistochemistry demonstrated a low-grade lymphohistiocytic infiltrate with scarce CD8+ cells and no detectable FOXP3+ regulatory T cells, indicating the absence of a pronounced immune response. An abundant presence of CD163+ M2 macrophages suggested polarization toward a regenerative phenotype. Strong SATB2 expression confirmed osteoinductive activity, while numerous CD34+ endothelial cells indicated active angiogenesis. Conclusions. The Nano Graft biomaterial exhibited low immunogenicity, characterized by a mild CD8+ T-cell response, absence of FOXP3+ regulatory T cells, and predominance of anti-inflammatory M2 macrophages. Its osteogenic potential and pro-angiogenic effects support its biocompatibility and clinical applicability for maxillary sinus augmentation.

Background: Maxillary sinus floor augmentation is widely used to enable implant placement in the atrophic posterior maxilla, yet comparative data for porcine-derived xenografts remain limited. Objective: To evaluate long-term bone regeneration and implant outcomes following sinus augmentation using a collagenated porcine xenograft. Methods: This paper reports a retrospective case series of three partially edentulous patients (aged 46-56 years) who underwent lateral sinus augmentation with a small-particle collagenated porcine xenograft (THE Graft™, Purgo Biologics, Gyeonggi-do, Republic of Korea) and staged implant placement. In one case, a controlled perforation of the Schneiderian membrane was performed to access and remove a sinus mucocele, followed by repair using a resorbable collagen membrane. Core biopsies were harvested at implant placement for histology (hematoxylin-eosin, Masson-Goldner) and tartrate-resistant acid phosphatase (TRAP) staining. Clinical outcomes included surgical events, vertical bone gain, marginal bone levels, and implant survival at long-term follow-up. Results: Healing was uneventful in all cases. Mean vertical bone gain was 12.0 mm (baseline 1.33 mm to 13.33 mm final). At a mean 46.8-month follow-up (range 38.3-52.2 months), 100% of implants were functional without failure; marginal bone loss remained < 1 mm during the first year and was stable thereafter. Histology at 3.7, 4.7, and 7.5 months showed vascularized new trabecular bone intimately contacting residual xenograft particles (new bone 20-30%, residual biomaterial 30-40%, connective tissue 30-50%). TRAP-positive multinucleated giant cells at 7.5 months indicated ongoing biomaterial degradation without severe inflammatory reactions. Conclusions: Within the limits of a small case series, collagenated porcine xenograft supported predictable bone regeneration and stable long-term implant function after sinus floor elevation, with favorable histologic integration and gradual resorption.

Aspergillosis is a common cause of fungal maxillary sinusitis that is often asymptomatic and detected only incidentally on imaging. It may be triggered by spores entering the maxillary sinus through the natural ostium, often following the dislocation of foreign bodies, for example root canal filling or augmentation materials. This retrospective study aimed to evaluate a standardised treatment for maxillary sinus aspergillosis followed by implant-prosthetic rehabilitation. Eleven immunocompetent patients with maxillary sinus aspergillosis were included in the present study. Maxillary sinus surgery was performed via a bone lid under local anaesthesia and intravenous sedation. The aspergilloma was removed completely and the diagnosis was confirmed by histopathology. Sinus disinfection consisted of irrigation with hydrogen peroxide (3%) and saline solution, followed by photodynamic decontamination. Three months postoperatively, a new CBCT scan was taken to confirm the absence of any pathology in the sinus. Sinus floor elevation and bone augmentation were then performed following a clear protocol. Implants were placed, whenever possible, simultaneously or after 3 months and exposed after another 3 months. The definitive prosthetic restoration followed 6 to 8 weeks postoperatively. The surgical procedures went without complications, and all patients were successfully restored. After 3 to 10 years (mean 6.8 ± 1.7 years), all inserted implants were still in place and presented with no inflammation, and with pocket depths below 5 mm (3.1 ± 0.9 mm). Postoperative radiographs showed no recurrence of any sinus pathology. The present treatment protocol proved to be efficient in managing infection and defect reconstruction. Throughout the 3- to 10-year follow-up period, neither recurrences nor complications presented, affirming the reliability of the protocol.

To explore the related risk factors of early failure of simple taper retentive implants, and to provide theoretical guidance for clinical work. Collect cases of patients who visited the Department of Stomatology of the Fourth Affiliated Hospital of Nanchang University from January 2021 to June 2024, received simple taper retentive implants, and had complete medical records. Taking the implants as the unit, analyze the influence of patient-related factors (gender, age, smoking history, hypertension history, diabetes history), implant-related factors (implant length, implant diameter, implant surface treatment), and surgical-related factors (implant site, implant timing, simultaneous maxillary sinus floor elevation, simultaneous bone augmentation) on the early failure of implants. Univariate analysis and multivariate analysis were adopted to explore the potential risk factors for early failure of simple taper retentive implants. A total of 3,533 simple taper retentive from 1,681 patients were included during the study period. Among them, 53 implants from 49 patients experienced early failure, with an early failure rate of 2.9% at the patient le-vel and 1.5% at the implant level. Multivariate analysis revealed that smoking (OR=2.148, P=0.021), the anterior mandibular region (OR=3.669, P=0.006), and the posterior maxillary region (OR=2.191, P=0.033) were risk factors for early failure of simple taper retentive implants. In the univariate analysis, simultaneous maxillary sinus floor elevation had a higher risk of early failure, but this effects was no longer significant in the multivariate analysis (P>0.05). Smoking, the anterior mandibular region, and the posterior maxillary region are risk factors for the early failure of simple taper retentive implants, and could be comprehensively considered in the preoperative treatment plan.

A Novel Robot-Assisted Access in Endodontic Microsurgery Combined with Sinus Floor Elevation for Maxillary First Molar.

Minimally invasive transcrestal sinus floor elevation: a 10-year cohort study.

To evaluate the accuracy of dental implant placement using fully guided static computer-assisted implant surgery (s-CAIS) and autonomous robotic computer-assisted implant surgery (r-CAIS) technology in patients with transcrestal sinus floor elevation. Patients with posterior teeth loss and transcrestal sinus floor elevation using s-CAIS or r-CAIS technology for implant surgery were included in this study. A total of 34 patients with 42 implants were included in the study (17 patients with 19 implants in the autonomous r-CAIS group, 17 patients with 23 implants in the fully guided s-CAIS group). Postoperative cone-beam computed tomography (CBCT) scans were used to determine the discrepancies between the planned and actually placed implants. The preoperative and postoperative CBCT were utilized to estimate the linear deviations and angular deviations in two-dimensional (2D) and three-dimensional (3D) space. A total of 42 implants were included, with significant differences between the autonomous r-CAIS group and fully guided s-CAIS group (p < 0.001). No adverse surgical events occurred. The 3D deviations at the implant platform were 0.484 ± 0.218 mm for the autonomous r-CAIS group and 1.179 ± 0.776 mm for the fully guided s-CAIS group, respectively. The mean linear deviations at the implant apex were 0.527 ± 0.247 and 1.196 ± 0.830 mm, respectively. The mean angular deviation was 0.882° ± 0.967° for the autonomous r-CAIS group and 2.478° ± 1.524° for the fully guided s-CAIS group. Autonomous r-CAIS technology provided a more accurate surgical approach for implant placement in patients with transcrestal sinus floor elevation than fully guided s-CAIS.

BackgroundIn previous studies, immediate implant placement in molar regions has been widely applied.PurposeTo study the clinical effect and feasibility of simultaneous implantation of implants combined with lateral maxillary sinus floor elevation in the maxillary molar region with severe bone defects.Materials and methodsPatients requiring lateral maxillary sinus elevation (LMSE) surgery in the maxillary molar region were selected. The patients (residual bone height, RBH < 3 mm) were randomly divided into two groups: the experimental group underwent simultaneous implant placement combined with LMSE; the control group first received bone augmentation via LMSE, followed by delayed implant placement. The outcome indicators included implant success rate, surgical complications, and measurements of Cone Beam Computer Tomography (CBCT) data.ResultsThe implant survival rate of both groups was 100%. One patient in each group experienced a maxillary sinus membrane perforation. From T1 (immediately after surgery) to T2 (9 months after surgery), both the bone height and bone width decreased in both the experimental group and the control group, and the bone resorption at the three sites (IBSH, MBH, DBH) in terms of bone height was greater than that in terms of bone width. The minimum bone resorption was observed at the IBSH site in both group. The amount of bone resorption in the experimental group at the above three sites was less than that in the control group, with statistical differences(p < 0.05). There was no statistical difference in the amount of bone width resorption between the two groups(p > 0.05).ConclusionIn cases where the bone volume is less than 3 mm, the method of simultaneous implantation with LMSE is feasible.

Background: To compare the histological and histomorphometrical outcomes after sinus floor elevation using an anorganic bovine bone biomaterial or a biphasic calcium phosphate biomaterial. Material and Methods: Patients who needed maxillary sinus elevation were included in this study. A total of 68 implant sites were evaluated from a total of 42 patients. Twenty patients were treated with anorganic bovine bone, while 22 were treated with biphasic calcium phosphate biomaterial. Morphological and morphometrical studies were performed on the bone samples collected during implant placement. Results: Both biomaterials induced similar relative areas of mineralized tissue overall, particularly if only the area of grafted bone was considered. In turn, a higher proportion of non-mineralized tissue was observed in cases of biphasic calcium phosphate biomaterial with less area of remnant biomaterial particles. None of the implants failed at one year of follow-up. Conclusions: Although both biomaterials induce a similar amount of bone formation, the histopathological characteristics of the grafts are different, with a greater proportion of scar connective tissue with the biphasic calcium phosphate biomaterial.

This study investigated the impact of sinus membrane thickening and perforation on graft remodeling following osteotome sinus floor elevation (OSFE). A total of 136 patients who received single implants with simultaneous OSFE were retrospectively analyzed and categorized based on preoperative sinus membrane thickness: membrane thickening (MT; > 2 mm, n = 38) and normal thickness (NT; ≤ 2 mm, n = 98). Cone-beam computed tomography was used to assess residual bone height and membrane thickness. Periapical radiographs obtained immediately postoperatively (T1) and at final follow-up (T2) were used to quantify sinus bone gain and apical graft height. The incidence of membrane perforation and implant survival was also documented. Implant survival rates were comparable between groups (MT: 97.4%, NT: 99.0%, p = 0.485). The incidence of membrane perforation occurred significantly more frequently in the MT group than in the NT group (21.1% vs. 6.1%, p = 0.010). Although final sinus bone gain was similar, apical graft resorption was significantly greater in the MT group compared to the NT group (2.3 ± 0.4 mm vs. 1.8 ± 0.6 mm; p < 0.001), resulting in a higher incidence of complete apical bone coverage loss (39.5% vs. 16.3%, p = 0.004). Furthermore, membrane perforation increased apical graft resorption risk regardless of membrane thickness. Sinus membrane thickening is associated with increased risk of perforation and greater apical graft resorption following OSFE. Thorough preoperative evaluation and careful surgical technique are essential to optimize outcomes, particularly in cases with thickened membranes.

BackgroundThe study aims to assess the effects of different treatments on postoperative hard tissue surrounding implants. This will be achieved through a retrospective analysis of patients with small antral pseudocysts (APs) measuring 20 mm or less, who received various management strategies for APs during lateral maxillary sinus floor elevation (LSFE).MethodsThis retrospective study examined 107 patients who underwent LSFE with concurrent implant placement, categorized into removal, aspiration, and untreated groups. The three-dimensional volumetric change rate of the bone graft within the maxillary sinus, the endo-sinus bone gain (ESBG), apical bone height (ABH), and peri-implant bone height (PBH) were assessed to quantify bone volume change. The marginal bone loss (MBL) and implant failure rate were evaluated to compare the success rates of implant surgery.ResultsAll implants demonstrated functionality without any failure or occurrences of sinusitis. Six months after surgery, the untreated group exhibited a significant reduction in bone graft volume (-18.31% [-19.72%, -15.24%]) compared to the removal group (-14.11% [-17.42%, -11.05%]) and the aspiration group (-16.55% [-18.71%, -11.83%]) (P < .001), alongside greater changes in ESBG and ABH (P < .01). PBH and MBL exhibited comparable values across the groups. Over a period of two years, bone graft stability was maintained, whereas, PBH exhibited a significant increase from six months to one year.ConclusionsThe findings of our study suggested that in LSFE, routine removal of small APs (diameter ≤ 20 mm), might be not required. A conservative treatment strategy for APs was advised to streamline the surgical procedure and enhance the success rate of implantation.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12903-025-07229-y.

Objective: Rehabilitation of the atrophic posterior maxilla is challenging due to insufficient bone quantity and quality. Conventional approaches, such as sinus floor elevation or onlay bone grafting, are associated with higher morbidity, longer treatment times, and increased complications. Pterygoid implants offer a less invasive alternative, utilizing dense cortical bone in the pterygoid apophysis and posterior maxillary tuberosity to provide distal anchorage and full-arch prosthetic support, while avoiding the need for sinus augmentation. Clinical evidence indicates high survival rates, making them a reliable option for posterior maxillary rehabilitation. Materials and Methods: This prospective clinical study included 15 patients (aged 49–78 years) with unilateral posterior maxillary tooth loss that was unsuitable for conventional implants. Each patient received one pterygoid implant and two compressive implants. Preoperative planning included CBCT scans. Surgical procedures involved flap elevation, precise drilling, and manual insertion with high insertion torque. Immediate prosthetic loading was performed within seven days. Postoperative care included antibiotics, analgesics, chlorhexidine mouthwash, and oral hygiene instructions. Implant failure was defined as detectable mobility or conditions requiring removal. Results: All 45 implants (15 pterygoid and 30 compressive) survived over the 12-month follow-up, with no failures observed at 3, 6, or 12 months. Survival rates were 100% for both implant types, and no differences were noted across follow-up periods. Conclusions: Pterygoid implants demonstrate high survival rates and represent a predictable, minimally invasive option for posterior maxillary rehabilitation. Proper preoperative planning and surgical expertise are essential, and further long-term studies are recommended to confirm standardized protocols and durability.

ABSTRACTHere, we present two Persian 58‐ and 39‐year‐old females with an edentulous posterior maxilla in the first molar region and a minimum residual bone height (RBH) of 4 mm. Sinus floor elevation with crestal approach was considered. Platelet‐rich fibrin (PRF) was utilized as a crucial safeguard during sinus floor elevation with the assistance of bone tap drills featuring round ends. The placement of cylindrical implants was carried out simultaneously. Before applying this technique “in vivo” on human subjects, the “ex vivo” efficacy of PRF‐assisted crestal sinus floor elevation with bone tap drills was evaluated. It seems that PRF‐assisted crestal sinus floor elevation with bone tap drills can be used as a simplified minimally invasive technique.

To compare the clinical and radiographic outcomes of crestal sinus floor elevation (SFE) using a digital surgical guide (DSG) and hydraulic sinus lift technique versus the conventional osteotome technique. Patients requiring crestal SFE and single-implant placement in the posterior maxilla with a minimum of 5 mm of residual bone height were included and randomly assigned to two groups of crestal SFE with (i) the conventional technique (elevation of a mucoperiosteal flap and SFE by the osteotome technique, control group) and (ii) by using a DSG (without flap elevation, by using the sinus lift hydraulic system in the presence of a DSG, test group). Frequency of intraoperative membrane perforation, surgical time, and patient-reported outcomes were collected. Crestal bone loss at 6 months, new bone formation in the sinus, and implant position were assessed. Twenty-three patients (24 implants, 12 in each group) were included. The DSG group experienced significantly lower postoperative pain (measured by the number of analgesics taken, 1.67 ± 0.77 vs. 2.75 ± 1.21, p = 0.028), shorter surgical time (22.3 ± 2.4 vs. 33.1 ± 4.1 min, p < 0.001), and smaller deviation of implant angulation from the ideal position (2.9° ± 0.6° vs. 8.6° ± 1.3°, p < 0.001) compared to the conventional group. The difference in other parameters was not significant. Considering the study limitations, using a DSG with a hydraulic system for crestal SFE was superior to the conventional technique regarding pain score, surgical time, and implant angulation. Due to the relatively small sample size and lack of statistically significant differences in some parameters, these findings should be interpreted with caution. Iranian Registry of Clinical Trials: IRCT20230529058333N1.