Displacement of the full body of a dental implant into the sinus space without membrane perforation and subsequent osseointegration: a case report

An increasing number of studies have investigated the use of osteotome sinus floor elevation (OSFE) with simultaneous implant placement for maxillary sinus floor residual bone height (RBH) <4 mm. Many studies have reported good clinical results, but very few have reported complications related to this procedure. Here, the case of a 50-year-old female patient with an RBH in the left upper posterior region of 1–4 mm, who underwent OSFE with simultaneous placement of three Bicon short® implants, is described. One of the implants was found to be displaced during the second-stage surgery. The displaced implant was removed using piezosurgery, OSFE with simultaneous implant placement was repeated, and the missing tooth was reconstructed 6 months later. This case suggests that OSFE with simultaneous implant placement is feasible for severely atrophic maxillary sinus floor, but carries a risk of implant displacement.

Clearance of Bone Substitute in Gel Form Accidentally Dispersed into the Sinus Cavity during Transcrestal Maxillary Sinus Floor Elevation: Two-Case Report

Sinus membrane perforation is the most frequent intraoperative complication occurring during maxillary sinus floor elevation. Although numerous techniques for perforation management are present, grafting material dissemination may still occur, representing a potential trigger factor leading to acute or chronic sinusitis. This case report describes two cases of xenogeneic bone substitute in gel form accidentally dispersed into the sinus cavity during maxillary sinus floor elevation with a transcrestal approach. In both cases, immediately postoperative radiographic imaging showed an important amount of gel graft dislodged into the sinus cavity as a consequence of hidden perforations that remained undetected during surgery. Patients were monitored for 6 months after surgery and reported no signs or symptoms related to possible sinus disease. Control radiographs showed no sinus membrane hypertrophy and/or presence of residual disseminated gel, confirming complete clearance of the accidentally dispersed graft through the ostiomeatal complex. In order to minimize postoperative complications, bone substitutes in gel form could represent an interesting alternative to granular grafts for their easier clearance from the maxillary sinus cavity in case of accidental dissemination during sinus augmentation procedures.

Effects of Platelet-rich Fibrin on Osteogenic Differentiation of Schneiderian Membrane Derived Mesenchymal Stem Cells and Bone Formation in Maxillary Sinus

BackgroundThe existence of mesenchymal stem cells (MSCs) in Schneiderian membrane has not been determined. The aim of this study is to investigate whether there are MSCs in Schneiderian membrane, and the effect of platelet-rich fibrin (PRF) on osteogenic differentiation of these cells and on new bone formation in maxillary sinus after maxillary sinus floor elevation.MethodsSchneiderian membrane derived mesenchymal stem cells (SM-MSCs) were isolate from rabbit maxillary sinus. Cells were identified by flow cytometry and multipotential differentiation. Real-time cell analysis assay, fluorescence staining, transwell assay, and wound healing assay were used to determine the effects of PRF stimulation on cell proliferation and migration. The osteogenic differentiation ability of cells stimulated by PRF or osteoinductive medium (OM) was evaluated by alkaline phosphatase (ALP) staining, alizarin red staining, PCR and Western blot. Equivalent volume Bio-oss and the mixture of Bio-oss and PRF were used as bone graft materials for maxillary sinus floor elevation. Micro-CT, bone double-staining, HE staining, Masson staining, and toluidine blue staining were used to evaluate the osteogenic effect in 8 and 12 weeks after surgery.ResultsThe cell surface markers were positive for expression of CD90, CD105, and negative for expression of CD34, CD45. SM-MSCs had the ability of osteogenic, adipogenic and chondrogenic differentiation. PRF can stimulate proliferation, migration and osteogenic differentiation of SM-MSCs, which is achieved by up-regulating ERK 1/2 signaling pathway. PRF can accelerate the formation of new bone in maxillary sinus and increase the amount of new bone formation. ConclusionsMSCs exist in Schneiderian membrane, and PRF stimulation can promote cell proliferation, migration and osteogenic differentiation. The application of PRF in maxillary sinus floor elevation can accelerate bone healing and increase the quantity and quality of new bone.

Patient’s perception of recovery after maxillary sinus floor augmentation with autogenous bone graft compared with composite grafts: a single-blinded randomized controlled trial

Background Autogenous bone graft is considered as the preferred grafting material for maxillary sinus floor augmentation (MSFA). However, harvesting of extraoral or intraoral autogenous bone graft is associated with risk of donor site morbidity and supplementary surgery. From a clinical and patient perspective, it would therefore be an advantage, if postoperative discomfort could be minimized by diminishing the need for autogenous bone graft harvesting. The objective of the present study was to test the hypothesis of no difference in patient’s perception of recovery after MSFA with autogenous bone graft from the zygomatic buttress (control) compared with 1:1 mixture of autogenous bone graft and deproteinized porcine bone mineral (DPBM) (Test I) or biphasic bone graft material (BBGM) (Test II). Sixty healthy patients were randomly allocated to either control or test groups. Oral Health-related Quality of Life (OHRQoL) was evaluated by Oral Health Impact Profile-14 (OHIP-14) at enrollment. Recovery was estimated by self-administrated questionnaires and visual analog scale assessing pain, social and working isolation, physical appearance, eating and speaking ability, diet variations, sleep impairment and discomfort after 1 week and 1 month. Descriptive statistics was expressed as mean with standard deviation (SD). Correlation between OHRQoL at enrollment and recovery were assessed by linear regression. p-value below 0.05 was considered significant. Results Treatment satisfaction and willingness to undergo similar surgery were high in all groups. Average numbers of days with pain and sick leave were 3.5 (SD 3.9) and 0.5 (SD 1.2), respectively, with no significant difference between groups. Moreover, no significant difference in eating and speaking ability, physical appearance, work performance and sleep impairment were seen between groups. Mean OHIP-14 score at enrollment was 9.30 (SD 9.25) (control), 9.95 (SD 7.96) (Test I) and 8.15 (SD 9.37) (Test II), with no significant differences between groups. Impaired OHRQoL, gender or age seems not to predispose for delayed recovery or increased postoperative discomfort. Conclusions MSFA with diminutive autogenous bone graft harvesting is associated with high patient satisfaction, limited postoperative discomfort and willingness to undergo similar surgery. Presurgical OHRQoL, gender or age seems not to be associated with impaired patient’s perception of recovery.

Biological notes of bone grafting in oral surgery

Introduction: the article presents the results of the outcomes analysis of bone grafting for dental implants, review some technical and biological factors that caused the success in this oral surgery. Also describes the different types of the maxillary sinus floor, «micro-window» technique for sinus-lifting and local bone modifying. This current aims to evaluate clinical outcomes after various bone grafting techniques for dental implan-tation, as well as to analyze the biological success factors of these surgery.Materials and methods: 134 bone grafting surgeries were performed - 23 men and 73 women. The patients were divided into 4 groups according to the methods: Guided Bone Regeneration (GBR); Bone Block (BB) transplantation; micro-window Sinus-lifting (mwSL); Local Bone Modifying (LBM).Results: The operations of the GBR and BB together showed an unsuccessful result in 72.36% of cases, while the bad outcomes of the mwSL and LBM operations were 7.7%. The better results were in groups with mwSL (success in 97.5%) and LBM surgery (87.1%).Conclusion: This demonstrates the clinical importance and effectiveness of various bone grafting methods. GBR and BB are less predictable in success, in contrast to mwSL and LBM, which we recommend. However, the factors affect the success of this surgery require further study.

Long-Term Clinical Study of Implants Placed in Maxillary Sinus Floor Augmentation Using Beta-Tricalcium Phosphate

Introduction. The aim of this study was to show the long-term clinical outcomes of implants placed in maxillary sinus floor augmentation (MFSA) using beta-tricalcium phosphate (β-TCP). Patients and methods. Maxillary patients were diagnosed for MFSA and used beta- β-TCP. After the lateral sinus surgery, implants were loaded at 6 months with restorations. The clinical follow-up was at 10 years. Results. One hundred and one patients (58 females and 43 males) were treated with MFSA. Twenty-nine patients (28.7%) had a history of periodontitis. Thirty-three patients (32.7%) were smokers. One hundred and twenty-one MFSA, 81 unilateral and 20 bilateral sites, with 234 implants were performed. The average vertical bone height available was 4.92 ± 1.83 mm. The average vertical bone gain obtained was 6.95 ± 2.19 mm following MFSA. The implant cumulative survival rate was 97.2%. Three implants (1.3%) were lost during the healing period. Six implants (2.6%) were lost by peri-implantitis. One hundred and fifteen restorations were placed in the patients. Mean marginal bone loss was 1.93 mm ± 1.03 mm. Six patients (27.3%) showed technical complications. Thirty-six implants (15.3%) in 14 patients (13.9%) were associated with peri-implantitis. Conclusions. This study indicates that treatment with implant-supported restoration by MFSA using β-TCP constitutes a successful implant approach.

Morphometric and histomorphometric evaluations of high-purity macro/microporous beta-tricalcium phosphate in maxillary sinus floor elevation: preliminary results on a retrospective, multi-center, observational study

Background The present study examined the effectiveness of high-purity macro/microporous beta-tricalcium phosphate (HPMM β-TCP) as a bone grafting material for maxillary sinus floor elevation by morphometric, histopathological, and histomorphometric evaluations. Methods Ten unilateral maxillary sinus floor elevation procedures using 100% HPMM β-TCP were performed in 10 patients. Morphometric evaluation was carried out by computed tomography (CT) imaging immediately after augmentation and prior to dental implant placement 7 months later. Histopathological and histomorphometric evaluations were carried out by bone biopsy retrieval at the time of dental implant placement 7 months after sinus floor elevation. Results All 10 sinus floor elevations were successful. Morphometric evaluation by CT showed that the vertical height and volume gained by sinus floor elevation decreased 7 months after surgery. Histopathological evaluation of bone biopsy retrieval specimens showed no signs of inflammation at the newly formed bone area and the native alveolar bone area. New bone formation was observed at the cranial side from the native alveolar bone. The newly formed bone had a trabecular structure and was in intimate contact with the HPMM β-TCP material. Histomorphometric evaluation of bone biopsy retrieval specimens showed an average new bone volume of 33.97% ± 2.79% and an average residual HPMM β-TCP volume of 15.81% ± 4.52%. Conclusions In this study, HPMM β-TCP showed osteoconductive properties for vertical augmentation of the atrophied maxilla by means of a maxillary sinus floor elevation procedure allowing subsequent dental implant placement after a 7-month healing period.