APCs in sinus floor augmentation.

After tooth loss in the posterior area of the maxilla, sinus floor elevation is often required to compensate the vertical bone loss due to sinus pneumatization. This narrative review reports on the potential benefits of autologous platelet concentrates (APCs) during this procedure. As for transcrestal approach, APCs have been used as "sole" substitute/graft. However, because of the low number of clinical trials available with PRGF, and even none for PRP, no definitive conclusions can be made regarding their efficacy. The number of studies on the use of L-PRF were outnumbered indicating good feasibility for vertical bone gain, with a high implant survival rate and a low degree of complications. PRP and PRGF have not been studied as a "single/sole" substitute for a one-stage lateral window approach, probably because of the weak physical characteristics of the membranes. L-PRF alone appears to be a predictable grafting material for lateral maxillary sinus grafting and a reduced RBH should not be considered as a risk factor. Compared to a "standard" bone substitute L-PRF shows slightly less vertical bone gain (consider enough membrane application and use of bony window as new sinus floor roof over the implant apices), enhanced early resorption (first 6 months after application), but a similar stable bone gain afterward. For a two-stage lateral window approach, APCs "alone" cannot be recommended, due to their weak withstand to the sinus pneumatization forces. APCs combined with bone substitutes seem to accelerate bone formation, without any additional benefits on the long-term new bone gain. The use of L-PRF membranes for the treatment of perforations appears to be an effective treatment option, but further clinical studies are needed to confirm this. Even though the abovementioned statements are based on large numbers of studies, additional RCTs comparing APCs with different types of grafting procedures for sinus elevation are needed.

Antral membrane balloon technique versus Densah bur in crestal sinus lift with simultaneous implant placement: a randomized clinical trial.

BACKGROUND: The posterior maxilla presents challenges for implant insertion because of the poor bone quality as well as the loss of vertical bone height. Indirect transcrestal sinus lift techniques are advised when a few millimeters of additional height are needed. This study aimed to evaluate the clinical and radiographic outcomes of antral membrane balloon technique versus Densah burs for transcrestal maxillary sinus lifting with simultaneous implant placement. MATERIALS AND METHODS: This randomized clinical trial was conducted on 22 patients received 32 dental implants for replacement of missed maxillary posterior teeth after crestal maxillary sinus lifting. The patients were randomly divided into two groups. Group 1, patients underwent crestal sinus floor elevation with simultaneous implant placement using antral membrane balloon technique. Group 2, patients underwent crestal sinus floor elevation with simultaneous implant placement using Densah burs. Patients were evaluated clinically and radiographically using cone beam computed tomography (CBCT) at regular time intervals immediately, 6 months and 12 months after surgery. All clinical and radiographic parameters were statistically analyzed. RESULTS: All dental implants were successful for 12 months of follow up. Regarding implant primary stability, there was a statistical significant difference between the study groups in favor of Densah group (P = 0.004), while there was no significant difference after 6 months (P = 0.07). Radiographically, balloon group showed a statistically significant immediate postoperative vertical bone height (P < 0.0001), and significant reduction in vertical bone height after 6 months (P < 0.0001). Densah group showed significant increase in bone density (P ≤ 0.05). CONCLUSION: Both techniques demonstrated successful clinical and radiographic outcomes for crestal sinus lift. The antral membrane balloon group demonstrated better immediate postoperative vertical bone gain, while Densah burs had higher implant primary stability and bone density. TRIAL REGISTRATION: This study was registered in Clinical-Trials.gov PRS ( https://register. CLINICALTRIALS: gov ) under identification number NCT05922592 on 28/06/2023.

The Use of Allograft Bone in the Lateral Approach of Sinus Floor Elevation: A Systematic Review of Clinical Studies.

Background and Objectives: The aim of this systematic review was to assess the efficiency of using allografts for sinus lift. Materials and Methods: This systematic review was written under the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and recommendation of the Cochrane Handbook for Systematic Reviews of Interventions. Three electronic databases were screened until October 2023. The risk of bias was assessed according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guidelines. Statistical analysis was performed for median bone volume and implant survival rate. Results: From 321 articles retrieved, 7 articles were included in this review. A comparison between freeze-dried bone allograft (FDBA) and deproteinized bovine bone (DBB) for mean bone volume indicated a weighted mean difference (WMD) of -0.17 [-0.69, 0.36] (95% confidence interval (CI)), p = 0.53. For implant survival rate, a comparison was made between FDBA and autogenous bone indicating a risk ratio (RR) of 1.00 [0.96, 1.05] (95% CI), p = 1.00. Conclusions: The available evidence suggested that allograft bone can be used in sinus lift procedures. The results obtained are insufficient to compare with other types of bone graft, requiring a longer follow-up time. Future clinical trials are needed in order to evaluate the advantages of using allograft bone.

[Elimination of defects in the Schneiderian membrane during sinus lift operations]. / Ustranenie defektov membrany Shneidera vo vremya provedeniya operatsii sinus-liftinga.

PURPOSE: Evaluation of the effectiveness of a new method of plasty of an extensive defect in the mucous membrane of the Schneiderian membrane, which occurs during the sinus lift operation, using an artificial collagen membrane and a developed method for fixing it. MATERIAL AND METHODS: A total of 188 patients took part in the study, all of these patients underwent an open sinus lift operation with simultaneous or delayed implantation. Operations were performed under balanced anesthesia. Six months after the operation, according to computed tomography, the height of the formed bone regenerate was estimated. In the area of each missing tooth, the initial bone height and the resulting bone grafting were assessed. Then we compared the average values before and after the operation, the average height difference before and after the operation. RESULTS: In 19 patients during the sinus lift there was an accidental extensive rupture of the mucous membrane of the maxillary sinus. Elimination of the mucosal defect was carried out according to our patented method. All 188 patients were diagnosed with partial loss of teeth with bone tissue deficiency in the distal maxillary sinus. The height of the alveolar process in the projection of missing teeth ranged from 0.5 mm to 5 mm. Delayed dental implantation was performed when the height of the alveolar bone was less than 3 mm, direct when the presence of 3-5 mm. After 6 months, dental implants were installed in the reconstruction zone, after another 6 months - rational prosthetics. CONCLUSIONS: The proposed method of plastic surgery has the following advantages. Firstly, it allows to eliminate the defect of the mucous membrane together with an increase in the height of the alveolar ridge. Secondly, after this method, the integrity of the mucous membrane will be restored. Thirdly, with an alveolar bone height of 3 mm or more, dental implants should also be installed.

Digitally Guided Lateral Sinus Floor Elevation With Simultaneous Implant Placement: 3 Case Reports With Technical Considerations.

A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla. Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon designs and locates the window after the flap is reflected based on the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardships in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring an LSFE simultaneous to implant placement, a maxillary sinus surgical guide has been tested and reported to be the amiable method to be utilized as a conjunct to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated based on 3D software. During surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. This technique makes the sinus window opening procedure simple and predictable, reduces surgical time and the risk of complications, and allows the placement of the implant in the ideal 3D position.

Digitally-Guided Lateral Sinus Floor Elevation with Simultaneous Implant Placement: Three Case Reports with Technical Considerations.

INTRODUCTION: A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla.  Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon design and locate the window after the flap is reflected based upon the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardship in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring a LSFE simultaneous to implant placement, a maxillary sinus surgical guide (MSSG) has been tested and reported to be the amiable method to be utilized as a conjunct, to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. CASE SERIES: This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus, as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated base on 3D software. During the surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. CONCLUSION: This technique makes the sinus window opening procedure simple and predictable, reduces surgical time as well as the risk of complications, and allows the placement of the implant in the ideal 3D position.

Resorbable magnesium metal membrane for sinus lift procedures: a case series.

BACKGROUND: The purpose of this case series was to demonstrate the use of a magnesium membrane for repairing the perforated membrane in both direct and indirect approaches, as well as its application in instances where there has been a tear of the Schneiderian membrane. CASE PRESENTATION: The case series included four individual cases, each demonstrating the application of a magnesium membrane followed by bone augmentation using a mixture of xenograft and allograft material in the sinus cavity. In the first three cases, rupture of Schneiderian membrane occurred as a result of tooth extraction, positioning of the dental implant, or as a complication during the procedure. In the fourth case, Schneiderian membrane was perforated as a result of the need to aspirate a polyp in the maxillary sinus. In case one, 10 mm of newly formed bone is visible four months after graft placement. Other cases showed between 15 and 20 mm of newly formed alveolar bone. No residual magnesium membrane was seen on clinical inspection. The vertical and horizontal augmentations proved stable and the dental implants were placed in the previously grafted sites. CONCLUSION: Within the limitations of this case series, postoperative clinical examination, and panoramic and CBCT images demonstrated that resorbable magnesium membrane is a viable material for sinus lift and Schneiderian membrane repair. The case series showed successful healing and formation of new alveolar bone with separation of the oral cavity and maxillary sinus in four patients.

Healing of particulate allografts mixed with platelet concentrates in ridge preservation and sinus lift: a prospective histomorphometric study.

The objective of the present study was to evaluate the bone quality of sinus and alveolar grafts following filling with particulate allogenous bone (DFDBA 300-500µm) and platelet concentrate (platelet-rich fibrin, PRF). A prospective interventional clinical study was carried out. A total of 40 bone cores, 2mm in diameter, were taken from 21 patients: 22 from grafted alveoli, 7 from grafted sinus sites, and 11 from native bone used as a control. Fixed, paraffin-embedded samples were subjected to histological staining with hematoxylin-eosin and Masson's trichrome. Bone maturity of the samples was evaluated by two independent operators using histomorphometric analysis. There existed a greater proportion of lamellar neoformed bone than woven neoformed bone as the healing time increased. Moreover, there was also an increasing proportion of newly formed bone in the grafted sockets as a function of healing time (average: 41.22% ≤ 5 months, 55.89% Ëƒ 5 months). Resorption of DFDBA particles also appears to be correlated with healing time in the grafted socket (average: 15.43 ≤ 5 months, 13.72% Ëƒ 5 months). In conclusion, performing sinus lift and alveolar socket preservation techniques using DFDBA and PRF results in high quality, mature bone tissue according to histological criteria.

Characteristics of maxillary sinus ostia and their correlation with anatomic variations of the osteomeatal complex: Indications for sinus floor elevation.

Background: Knowledge of the anatomy and variations of the maxillary sinus is essential for reducing oral surgery complications, such as sinus floor elevation, and increasing surgery success. The CBCT images of 385 patients were examined. Materials and Methods: The prevalence, localization, and height of PMO (Primer Maxillary Ostium) and AMO (Accessory Maxillary Ostium) were evaluated with respect to sex, dentition, dental treatment, Schneiderian membrane (SM) thickness, concha bullosa, Haller Cells, and septal deviation. Results: The PMO was present in 87.3% of all patients. Further analysis showed that the mean PMO diameter was 1.42 ± 0.62 mm. Although 11.6% of the PMO was in the inferior region, 60.4% was in the middle and 28% in the superior region. The effect of age and SM on the height and diameter of the PMO was found to be statistically significant. An AMO was present in 20% of the CBCT images. The mean AMO diameter was 2.55 ± 1.25 mm. Although 45.4% of the AMO was in the inferior region, 48% was in the middle and 6.6% was in the superior region. Moreover, SM thickness seemed to influence the height. A significant positive relationship was found between the PMO and AMO height. Also, a significant relationship was observed between the presence of the AMO and septum deviation. Conclusion: The presence of the AMO, PMO diameter, and height should be added to the preoperative evaluation criteria for the success of sinus floor evaluation. Specifically, sinonasal and demographic conditions should be carefully examined preoperatively for the long-term success of the surgery.

Evaluation of immediate implant placement with osteotome sinus floor elevation without graft material.

Background: Significant difficulties can be encountered when installing posterior maxillary implants. Osteotome sinus floor elevation (OSFE) enables insertion of implants with insufficient bone height at the posterior maxilla using a special instrument known as the "osteotom." Aim: This study aimed to evaluate the implant survival rates and radiographical bone gain data after OSFE with simultaneous implant placement performed without grafting material. Further, we have discussed whether the osteotom tapping distance to sinus floor affects the amount of new bone gain (NBG). Materials and Methods: Forty dental implants were inserted in 36 patients (20 women and 16 men) aged between 24 and 80 years (mean = 55.7 years). Residual bone height and NBG were analyzed using a commercially available software program on panoramic films. Results: The mean residual bone height at the intended implant sites was 5.4 mm ± 2.2 mm, ranging from 3.5 mm to 6.9 mm. The mean NBG was 1.5 mm ± 0.87 mm, ranging from 0.1 mm to 4 mm. At 64.4 months of follow-up, one implant had been lost in the osseointegration period. The remaining 39 implants were in function, with a survival rate of 97.5%. No significant difference was seen between the osteotome tapping distance to sinus floor and NBG at the implant apex (P = 0.395). Conclusion: OSFE without using bone grafts with simultaneous implant installation is a safe and reliable method with successful long-term results for he rehabilitation of edentulous posterior maxillae.

SMOKERS MAY BE SUBJECT TO A HIGHER RISK OF SCHNEIDERIAN MEMBRANE PERFORATION THAN NONSMOKERS DURING MAXILLARY SINUS AUGMENTATION.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Association between smoking and Schneiderian membrane perforation during maxillary sinus floor augmentation: A systematic review and meta-analysis. Wang, X., Ma, S., Lin, L., & Yao, Q. Clinical Implant Dentistry and Related Research. 2022., 25.1: 166-176. SOURCE OF FUNDING: National Natural Science Foundation of China, Grant/Award Number: 81801021; Hunan Provincial Health Commission, Grant/Award Number: B202308056991. TYPE OF STUDY/DESIGN: Systematic review and meta-analysis.

Use of hyaluronic acid for regeneration of maxillofacial bones.

Hyaluronic acid (HA) has been widely used in medicine and is currently of particular interest to maxillofacial surgeons. Several applications have been introduced, including those in which HA is used as a scaffold for bone regeneration, either alone or in combination with other grafting materials, to enhance bone growth. This review aims to analyze the available literature on the use of HA for maxillofacial bone regenerative procedures including socket preservation, sinus augmentation, and ridge augmentation. Medline and PubMed databases were searched for relevant reports published between January 2000 and April 2021. Nine publications describing the use of HA to augment bone volume were identified. Although further studies are needed, these findings are encouraging as they suggest that HA could be used effectively used, in combination with graft materials, in maxillofacial bone regenerative procedures. HA facilitates manipulation of bone grafts, improves handling characteristics and promotes osteoblast activity that stimulates bone regeneration and repair.

Effects of ultraviolet irradiation on beta-tricalcium phosphate as a bone graft substitute.

Surface modification of various materials using ultraviolet (UV) irradiation improves their wettability. The purpose of this study was to investigate the wettability of a ß-tricalcium phosphate (TCP) surface and the composition changes and bioactivity of ß-TCP after UV irradiation. We applied 172 nm UV treatment to a ß-TCP surface and measured the contact angle before and after UV irradiation. Energy-dispersive X-ray and Fourier transform infrared spectroscopy examinations were performed on the ß-TCP disk with or without UV treatment. In an adhesion test of bone marrow cells using ß-TCP disks with and without UV irradiation, cell attachment was measured 10, 30, 50, and 70 h after ß-TCP insertion. UV-irradiated ß-TCP osteogenesis and absorption of bone substitutes were evaluated using hematoxylin and eosin and tartrate-resistant acid phosphatase (TRAP) staining in a rabbit sinus model. The contact angle on the TCP surface decreased from 70° to 10° owing to UV irradiation. Conversely, UV irradiation did not change the composition of carbon, oxygen, and phosphorus. In the cell adhesion test, UV-irradiated ß-TCP significantly increased cell adhesion compared with UV-unirradiated ß-TCP after 10 to 30 h of culture. In the rabbit sinus model, TRAP staining showed that UV-irradiated ß-TCP significantly increased the number of TRAP-positive cells compared with unirradiated ß-TCP granules in the central part of ß-TCP. Our results indicate that the UV irradiation of ß-TCP improves its clinical utility for surgical bone augmentation in the oral and maxillofacial region.

Comparative Assessment of the Primary Stability of Straumann BLX Implant Design Using an In Vitro Sinus Lift-Simultaneous Implant Insertion Model.

Straumann BLX is a novel implant system that has been proclaimed to provide an ideal primary stability in all types of bone. In the current study, the primary stability of the Straumann BLX implant systems with Straumann tapered effect (TE) implants have been comparatively assessed in bovine ribs by using a simultaneous sinus elevation and implant insertion model. In the study group, BLX (4.0 × 12 mm), TE (4.1 × 12 mm), BLX (4.5 × 12 mm), and TE (4.8 × 12 mm) were placed in each bony window, which resembles the sinus maxillaris. As a control, BLX and TE implants with the same sizes were inserted into the proximal diaphysis of the bovine ribs. A total of 40 implant insertions were performed. Stability was measured with resonance frequency analysis. In the study group, 4.8-mm TE implants showed significantly higher values compared with 4.5-mm BLX implants (P = .116). However, 4.0-mm BLX implants in the control group showed higher stability compared with 4.0-mm-diameter TE (P = .014). The primary stability of the BLX implants in the control group was significantly higher compared with the experimental group in both widths (P= .018 for BLX 4.0 mm and P = .002 for BLX 4.5 mm, respectively). The use of the TE design with a wide diameter in simultaneous implant placement with sinus lift could present higher implant stability quotient values and might be a more appropriate option for implant recipient sites with poor bone volume and quality. However, the advantage of BLX design in standard implant insertion protocols could be of value.

Clinical and Histological Outcomes of Maxillary Sinus Floor Augmentation With Synthetic Bone Substitutes for Dental Implant Treatment: A Meta-Analysis.

The main objective of this study was to compare the clinical and histological results of synthetic bone substitutes used in maxillary sinus floor augmentation. A systematic review and meta-analysis was performed by searching the PubMed/MEDLINE, Scopus, and Cochrane databases for studies of the success of endosseous dental implant, implant failure, peri-implant marginal bone loss, newly formed bone, and residual bone graft material. After the search, 10 randomized clinical trials were included, with 4 studies ranging from low to unclear risk of bias were used for meta-analysis, comparing biphasic calcium phosphate (BCP) and deproteinized bovine bone (DBB). A greater amount of residual graft material (mean difference [MD]: -4.80 mm; 95% CI: -9.35 to -0.26; P = .040) was found in the DBB group. No other statistically significant differences were found between BCP and DBB for the remaining outcomes. Our results suggested that BCP can be considered a suitable alternative to DBB in maxillary sinus floor augmentation due to its clinical and histological results.

Evaluation of Sinus Membrane Perforation in Osteotome Sinus Floor Elevation With and Without Grafting.

The purpose of this study was to evaluate, using cone-beam computerized tomography (CBCT), the rate of sinus membrane perforation in osteotome sinus floor elevation (OSFE) performed with and without a graft material. Thirty patients with 52 OSFE sites were included in the study. Patients were divided into the control group (OSFE performed without graft material) and test groups (OSFE performed with autograft or xenograft). The autograft was harvested from the maxillary tuberosity using bone forceps. The xenograft was a commercial product originating from bovine bone. Graft volume was measured using the water displacement method. CBCT was performed at the initial examination and immediately after surgery to measure the residual bone height and to evaluate the endo-sinus bone gain and membrane perforation. The rate of sinus membrane perforation was 15.4%. Of the 52 OSFE procedures, 26.9% were performed without grafting and 34.6% and 38.5% were performed with autografts and xenografts, respectively. Membrane perforation was significantly higher in the autograft group (P = .033). The median volume of graft materials was 0.3 mL. The difference in graft volume between the autograft and xenograft was not statistically significant (P = .768). The mean endo-sinus bone gain was 6.55 mm in patients without membrane perforation and 8.71 mm in patients with membrane perforation; this difference was statistically significant (P = .035). The volume and physical properties of graft materials are important factors in membrane perforation. Further clinical studies with larger and standardized samples are needed to confirm the effect of graft materials on sinus membrane perforation in OSFE.

Guided sinus lift: virtual planning of surgical templates for lateral access.

The sinus lift with lateral approach is a regenerative technique nowadays considered predictable to increase the height of bone in the atrophic posterior maxilla. Knowledge of sinus anatomy and evaluation of risk factors are the basis of regenerative and rehabilitative surgical success. The positioning and size of the lateral antrostomy represent critical factors in the execution of regenerative surgery, due to the difficulty in transferring radiological information to the lateral wall of the maxillary sinus even for skilled surgeons. The knowhow of guided implant surgery in recent years is also finding use in planning and precisely delineating the lateral access to the maxillary sinus using CBCT imaging and dimensional reconstruction software, through the realization of surgical guides with 3D printing, as shown in the presented case.

Management of large perforations of the sinus mucosa with PRGF-Endoret® platelet concentrate.

The aim of the present study is to describe a new technique through which it is possible to complete the maxillary sinus lift procedure even in case of severe damage or complete removal of the sinus mucosa using the PRGF-Endoret® platelet concentrate. Eighteen patients (ratio F:M=4:5; average age: 58.2 years; DS: 8.85 years) with severe perforation (more than 10 millimetres of diameter) of the sinus mucosa during the maxillary sinus lift procedure were selected. Normally the procedure is interrupted due to impossible stabilization of the graft material inside the subantral cavity. On the contrary, our protocol foreseen the sealing of the perforation using the PRGF autologous gel membranes or the creation of a new sinus pseudomembrane through which the graft material was covered. The PRGF-Endoret were obtained according to the protocol developed by BTI (Biotechnology Institute - Vitoria, Spain). In 14 cases out of 18 implant fixtures were concurrently inserted while in 4 cases the fixture insertion was postponed after 6 months: 37 fixtures were inserted (27 at the same time and 10 after 6 months). 2 months after surgery the CBCT showed a correct pneumatization of the maxillary sinus in 16 patients out of 18 (89% of cases), while after 12 months the radiological normalization of the maxillary sinus was present in 17 patients out of 18, bringing the healing rate to 94% of cases. Regarding implant healing, 2 out of 37 implants inserted were lost in the first month after the surgical phase, whereas 12 months after prosthesis application the other 35 implants were perfectly osteointegrated with a healing rate equal to 94.6% of the fixtures. 36 months after the surgery all the fixtures were osteointegrated (35 of 37 implants with a percentage of 94.6% of success). We may conclude that the use of PRGF allowed to complete the sinus lift even in case of severe perforation of the sinus mucosa or its total removal thanks to its capability to stabilize the graft, its antibacterial and antifungal activity and its anabolic effect and favouring bone regeneration.

Delayed post-extraction implants placed using a modified Summers technique: Preliminary results of a single cohort study.

The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of the patients that underwent implant surgery with a modification of the sinus lift summers protocol. Forty healthy patients in need for oral rehabilitation with dental implants were included in this study. Inclusion criterion was the need for extraction of one compromised tooth due to persistent abscess/ periodontitis/cyst in the atrophic posterior maxilla region. The treatment consisted of two stage surgery for all patients. In the first stage, after tooth extraction, the sockets were preserved with allogenic bone graft and equine collagen membrane. After 4-5 months, 40 implants with a sandblasted surface, were inserted with osseodensification technique and a modification of the Summers sinus lift protocol for fracturing the sinus floor. The implant survival rate was the primary outcome. Intra- and postoperative complications were additional criteria for success. The mean follow-up from implant surgery was 28.0±7.3 (standard deviation) months (range 17.8-43.4 months). One implant was lost before the delivery of the prosthesis. The overall implant survival rate was 97.5%. The overall mean peri-implant marginal bone level change after 6 and 12 months of function was, respectively, 0.26±0.24 mm (95% CI: 0.19, 0.34 mm) and 0.71±0.36 mm (95% CI: 0.60, 0.82 mm). Marginal bone loss was statistically significant at both time frames respect to implant placement, and also the difference between 6 and 12 months was significant (p<0.001 in both cases). No biological nor mechanical complications were recorded throughout the observation period. As a conclusion, the technique presented in this cohort study can be an effective and safe alternative to standard maxillary sinus floor augmentation procedures and immediate implant insertion protocol, especially in cases of periodontitis and infected sites, which can represent a high risk for implant failure in patients with atrophic posterior maxilla.

Palatal root surgery of a maxillary molar using a piezosurgery transantral approach with simultaneous sinus lift grafting: a case report.

AIM: To report a case involving transantral palatal root piezoelectric surgery followed by a sinus floor augmentation procedure with the purpose of minimizing and managing complications associated with sinus lining perforations and optimizing bone regeneration at the site of the surgical defect. SUMMARY: An asymptomatic 28-year-old male patient with the diagnosis of chronic apical periodontitis on a previously root filled right maxillary first molar (FDI tooth 16) and second premolar (No. 15) was managed by transantral apical surgery. Cone-beam computerized tomography (CBCT) revealed the position of the palatal root of the first molar within the maxillary sinus. The case highlights the management of the palatal root and the handling of a perforation of the Schneiderian membrane through a combination of piezosurgery and a sinus lift grafting procedure involving a second-generation of platelet concentrates. No postoperative complications were observed. Sinus bone augmentation after a 26-month recall period was confirmed by CBCT in the clinically asymptomatic teeth. KEY LEARNING POINTS: The selective bone tissue cutting and enhanced visibility obtained by piezoelectric surgery in comparison with current rotary techniques make this technology the preferred tool for apical surgery when the mucosal lining of the maxillary sinus could be compromised. The wound healing and physical properties of the platelet-rich fibrin membranes in combination with an allograft material can be considered as sinus bone graft options when a transantral approach is performed on a palatal root of a maxillary molar. A preoperative tomographic examination is essential for apical surgery using a transantral approach with sinus bone augmentation, because of the information obtained from the axial and coronal views on the CBCT scan.