Sinus Membrane Perforation Research Articles

A systematic review of sinus floor augmentation complications. Does graft type influence the complications rate?

Background. Sinus floor elevation is considered a safe procedure to properly augment the height of the edentulous crest. Often, complications may arise due to multiple causes and can lead to a poor outcome of the graft and implant’s osseointegration. A careful surgical approach, a good knowledge of possible obstacles, and careful treatment planning can reduce the risks of complications, as well as their impact on the surgical outcome. This study aims to make a literature review of 40 articles, analyzing the incidence and type of complications related to maxillary sinus graft surgeries and graft materials. Material and methods. A total of 40 articles published between 2015 and 2021 were selected for a systematic literature review on maxillary sinus floor complications. The studies were selected from 2 different internet databases: PubMed and Science Direct. The sinus lift complications were counted and their incidence was organized upon the surgical technique and the timing of occurrence (intraoperative, postoperative). It was also analyzed if the graft material influences the complication rate. Results. In a group of 1757 sinus augmentation surgeries performed on 1605 patients, 363 complications were found. Sinus membrane perforation occurred in 242 cases, 29 procedures resulted in partial or total graft loss, there were 26 postoperative cases of sinusitis, 24 sinus infections, 16 wound dehiscence, 6 bleeding complications, 5 lost implants, and 2 oro-antral fistulas. Conclusion. Sinus lift complications are sometimes inherent circumstances of the procedures, but they can also be prevented through an accurate technique and preoperative plan. The type of bone graft does not influence the incidence of surgical complications.

Efficacy of Two Different Hydrodynamic Sinus Lift Systems for Atraumatic Elevation in Immediate Implant Placement.

To evaluate the efficacy of two hydrodynamic sinus lifting procedures and to successfully place immediate implants in maxillary posterior sites that have a compromised native bone as a result of periodontal or endodontic disease. A total of 26 patient sites were enrolled with 13 sites each in the Minimally Invasive Antral Membrane Balloon Elevation (MIAMBE) and Drill Integrated Hydrodynamics for the transcrestal sinus floor elevation (DIHSFE) groups who received transcrestal sinus floor elevation followed by immediate implant placement. Clinical parameters such as sinus membrane perforations, nasal bleeding, postoperative sinusitis, VAS scores at Day-7 for pain and discomfort, primary implant stability and time taken were evaluated. The DIHSFE had greater sinus membrane perforations and incidence of nasal bleeding when compared with MIAMBE with (p = 0.066) and (p = 0.141). Post-operative sinusitis was evident in both the groups with (p = 0.619). The mean VAS score was statistically significant between both the groups (p ≤ 0.005). The insertion torque values, and mean time taken for surgical procedure was not statistically significant between groups. The present study highlighted that MIAMBE is superior to DIHSFE in its ability to cause less severe patient morbidities and post-operative complications.

One-Month Postoperative Reentry for Maxillary Sinus Floor Augmentation After a Large Sinus Membrane Perforation: A Retrospective Clinical and Radiographic Analysis.

The aim of this retrospective analysis was to evaluate the clinical and radiographic results of a shortened protocol (using a lateral approach) for early surgical reentry, following a large sinus membrane perforation that occurred during maxillary sinus augmentation (lateral approach), for the rehabilitation of patients with an atrophic posterior maxilla. Between May 2015 and October 2020, seven patients underwent reentry surgery using a lateral approach protocol 1 month after a large sinus membrane perforation during maxillary sinus floor augmentation with lateral approach surgery. All patients presented a residual under-sinus bone height < 3 mm in the posterior maxilla. The sinus membrane was elevated during the reentry surgery, without any difficulty for any patient, using manual blunt elevators or piezoelectric devices, and the sinus floor height was augmented with bone substitute particles. No further perforations were made, and no complications were recorded during the follow-up period from 18 months to 6 years. The 1-month waiting period after the initial sinus surgery allows easy sinus membrane elevation and a lack of complications. This timing could be a feasible option for surgical reentry after a large sinus membrane perforation occurs. Int J Periodontics Restorative Dent 2023;43:241-246. doi: 10.11607/prd.6463.

Risk factors and longitudinal regenerative outcomes of sinus membrane perforation during lateral window sinus floor elevation: A retrospective analysis up to 9 years.

Lateral-window sinus floor elevation (LSFE) is a reliable procedure to reconstruct the posterior maxilla for implant therapy. This retrospective study aimed to investigate risk factors associated with Schneiderian membrane perforation (SMP) occurrence during LSFE and longitudinal regenerative outcomes following LSFE up to 9 years. Patients who had LSFE between 2010 and 2019 were included. All demographic and surgical-related data were retrieved from existing electronic health records. Radiographs were used to evaluate the vertical dimensional changes of ridge and graft materials and the potential anatomic factors of SMP. A total of 122 LSFE procedures in 99 patients were included in the study. Mean ridge height gain and graft shrinkages were 9.5±3.47 and 1.57±2.85mm. The influence of the healing period on graft shrinkage showed a positive trend; the longer the healing period, the greater the graft shrinkage (p=0.09). The pathology in the sinus showed a positive correlation with SMP (p=0.07). However, other anatomical factors did not negatively impact SMP and subsequent ridge height gain (p>0.05). With inherent limitation, the findings with up to 9 years of follow-up indicate a consistent ridge remodeling lasting for about 3 years after LSFE procedures. SMP or membrane thickening may not significantly affect the ridge gain following LSFE. The healing period had the most significant influence on graft shrinkage, showing that the longer the healing time between LSFE and implant placement, the greater the graft shrinkage.

Lateral Window Maxillary Sinus Augmentation – Complications and Management

Introduction: The sinus lift procedure is the most predictable surgical intervention for enhancing bone quality and quantity in the posterior maxilla prior to the placement of endosseous dental implants. However, despite careful planning and precise surgical technique, several complications can arise. These include - haemorrhage, membrane perforation, infection, wound dehiscence, post operative pain, implant failure/ loss, graft loss, hematoma, barrier membrane exposure, oroantral fistula and sinusitis. Aim: The purpose of this report was to address the most common complications associated with the sinus lift procedure and discuss how to avoid and manage them when they occur. Methodology: A total of 140 articles from peer reviewed journals published in English from January 1986 to January 2023 were collected from a search performed using MEDLINE and PubMed. The keywords utilized were “dental implant”, “sinus augmentation”, “sinus complication”, “membrane perforation”, “bleeding – sinus augmentation”. Twenty-nine of the 140 articles satisfied the inclusion criteria and were utilized in this article. Results: Sinus membrane perforation is the most prevalent complication of maxillary sinus augmentation procedures, ranging from 11-60%. An incidence of 28% perforation rate is found. Bleeding was reported with an incidence of 2% of the sinus procedures performed. The use of piezoelectric devices as well as other measures play an important role in ensuring the stopping of bleeding. Conclusion: Proper planning and management of these complications will minimize the negative effects on therapy and allow for a successful implant result when placed in augmented maxillary sinuses.

Analysis of the Prevalence, Location, and Morphology of Maxillary Sinus Septa in a Northern Chinese Population by Cone Beam Computed Tomography.

Purpose The purpose of this study is to survey the prevalence and morphology of the maxillary sinus septum, which might increase the rate of maxillary sinus membrane perforation during maxillary sinus floor elevation surgery, among northern Chinese, and to further analyze the relationship between gender, age, edentulous type, and prevalence of maxillary sinus septa. Methods The cross-sectional retrospective study was based on an analysis of Cone Beam Computed Tomography (CBCT) images of maxillary sinus which had been obtained from patients who visited radiology department of Beijing Stomatology Hospital of Capital Medical University (Beijing, China) during the period from January 2019 to December 2019. The data of demographic characteristic, prevalence, position, direction, and morphology of maxillary sinus septum were collected and further analyzed by SPSS version 25.0.1 and R version 3.5.1 software program. Results 595 patients were included in this study, and 1190 maxillary sinuses were analyzed and the incidence rate of the sinus septum was 46.9%. 399 (33.5%) sinuses had one or more septa in 279 (46.9%) patients. In addition, maxillary sinus septa incidence showed no significant differences among gender, age, and edentulous type. The segment second molar had the highest incidence rate of septa. Conclusion In this study, a higher incidence of the maxillary sinus septum was found in the northern Chinese, and its distribution varied with its position, morphology, and direction.

Incidence of Sinus Membrane Perforation Using Two Types of Implant Drills: An Ex Vivo Animal Study.

This ex vivo study evaluates the incidence of sinus membrane perforation during implant site osteotomy with two different types of drills and drilling techniques. Fifty goat heads with 50 sinus pairs (100 sinus sides) were assigned to two groups (osseodensification bur [OB] group and inverse conical shape bur [ICSB] group) to simulate transcrestal sinus elevation (50 sinus sides per group). An osteotomy was performed to pass through the lateral sinus wall no more than 3 mm. The integrity of the sinus membranes was examined and confirmed under a microscope. Of the 50 sinuses per group, the OB group presented with 14 (28%) perforated sinuses, while the ICSB group presented with 2 (4%) perforated sinuses. Of the 14 perforations from the OB group, 6 (42.9%) showed a pinpoint perforation pattern, 4 (28.5%) of which were not visible until direct air pressure was applied. Overall, the ICSB drill group demonstrated a lower sinus perforation rate than the OB group.

Low Window Sinus Elevation Technique: Bone Gain and Postsurgical Discomfort. A Retrospective Case Series.

Recently, the Low Window technique was proposed to facilitate sinus augmentation and reduce postsurgical patient discomfort. It was shown to be both safe and effective. This case series evaluates the postsurgical discomfort of patients undergoing Low Window sinus augmentation, the bone gain achieved, and whether these factors correlate with the osteotomy area. Records of patients (n = 26) who underwent a sinus elevation using the Low Window approach (n = 34 interventions), followed by implant placement and prosthetic rehabilitation (n = 97 implants), were assessed retrospectively. The analyzed outcomes were the medial, middle, and lateral bone gain ≥ 9 months after augmentation; pain at 5 to 6 hours postsurgery, evaluated on a visual analog scale (VAS; 0 to 100); pain, swelling, and hematoma formation every day up to 7 days postsurgery, evaluated by VAS; implant and prosthetic success and survival rates; and rate of complications. The average follow-up time was 62.1 ± 14.9 months. No intraoperative sinus membrane perforations or other complications occurred. Medial, middle, and lateral bone gains were 10.1 ± 1.7 mm, 11.6 ± 0.8 mm, and 10.7 ± 0.9 mm, respectively. At the last follow-up, the implant success rate was 99%. Postsurgical VAS pain 5 to 6 hours postsurgery was 12.3 ± 8.0 and decreased significantly thereafter. Swelling prevalence was 29.4% at 1 day postsurgery, 20.6% at 2 days, and 2.9% the following day. No swelling was observed from day 4 onward. Prevalence of hematoma was 8.8% for 2 days postsurgery, 2.9% the day after, and no hematoma was observed thereafter. Only the osteotomy area correlated with immediate postsurgical pain, but not with other discomfort outcomes or with bone gain. Low Window sinus elevation might allow bone gain and medium-term implant and prosthetic success rates similar to that of other access window designs. Prospective, comparative studies are needed to investigate whether the technique is more advantageous than traditional approaches.

Intraoperative complications and early implant failure after transcrestal sinus floor elevation with residual bone height ≤5 mm: A retrospective multicenter study.

ObjectiveClinical indications for maxillary sinus floor elevation with transcrestal techniques have increased in recent years even in sites with minimal residual bone height (RBH). Nevertheless, limited information is currently available on incidence of intraoperative complications and early implant failure in these cases.Material and MethodsThis retrospective multicenter study was performed on anonymized clinical and radiographic records of patients who underwent transcrestal sinus floor elevation in seven clinical centers. Influence of different factors related to patient, and sinus anatomy and surgical technique on the incidence of intraoperative complications and early implant failure rate after transcrestal sinus lift were investigated.ResultsA total of 430 patients treated with transcrestal sinus floor elevation for single‐implant insertion in sites with RBH ≤5 mm were included in the final analysis. After 1 year of loading, 418 implants of 430 were satisfactorily in function. Early implant failure was recorded in 12 cases (2.8%); results were significantly associated with the presence of large sinus cavities and with the occurrence of membrane perforation.The following adverse events were recorded: membrane perforation (7.2%), acute sinusitis (0.9%), implant displacement into the sinus cavity (0.7%), oro‐antral fistula (0.2%), and benign paroxysmal positional vertigo (0.5% of osteotome cases). A strong direct correlation between sinus membrane perforation and bucco‐palatal sinus width (p = .000) was demonstrated.ConclusionsEarly implant failure after transcrestal sinus elevation showed significant direct correlation with bucco‐palatal maxillary sinus width and the presence of membrane perforation. Sinus membrane perforation was strongly associated with bucco‐palatal sinus width (extremely low perforation rate in narrow and much higher incidence in wide sinuses).

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.

PERFORATION OF SINUS MEMBRANE DURING SINUS FLOOR ELEVATION: REPAIR WITH COLLAGEN MEMBRANE AND METHOD RELIABILITY

Introduction: Sinus floor elevation (sinus lift) constitutes one of the most predictable methods of bone augmentation in the maxillary posterior region. However sinus membrane perforation during this surgical procedure may be an aggravating factor for the final bone augmentation outcome, thus a number of techniques have been introduced for immediate sinus membrane repair. Aim: The scope of this scientific work is to present the application of collagen membrane surgical technique, which is a widely used technique for sinus membrane repair after sinus membrane perforation when performing sinus lift. Moreover, the outcome of this surgical technique in terms of bone augmentation and implant osseointegration are also presented, as well as an extensive literature review on this subject. Materials and Methods: 106 cases with sinus floor elevation were performed within a period of 3 years, accounting for a series of 12 cases with sinus membrane perforation. In all 12 cases sinus membrane repair took place with the application of a collagen membrane. Results: In 3 out of 106 cases of sinus floor elevation inflammation of the involved maxillary sinus was noted but none of these 3 cases was implicated with sinus membrane perforation. Conclusions: Taking into account the data of the present work, as well as an extensive literature review on this subject, immediate repair with collagen membrane after sinus membrane perforation when performing sinus lift, is a very effective technique for maxillary bone augmentation.

The Comparison of Methods for Bone Reconstruction in the Anterior Wall of the Maxillary Sinus (an Experimental Study).

The aim of the study was to compare various methods used for the bone reconstruction in the anterior wall of the maxillary sinus during sinus lift surgery; in addition, we aimed to study the effect of maxillary sinus membrane perforation on the healing process.Materials and MethodsThe experiments were carried out using the North Caucasian sheep. Maxillary sinus lift surgery was performed on the animals under general anesthesia. The skin and muscle fascia were dissected layer-by-layer providing the optimal conditions for bone preparation; then, three bone windows were made on each side of the head. Two windows were sawn out with a spherical bur, the third window — with a hollow bur and part of the anterior wall was taken out. On one side, the mucous membrane of the maxillary sinus was pulled and perforated; on the other side, the sinus lift was performed with no membrane perforation. On each side, one window was left uncovered, the second was closed with a collagen membrane, and the third was closed with a bone cover. After 30 and 60 days, the sheep were taken out of the experiment in groups of three; samples were collected from the operated areas and examined using computed microtomography and histology.ResultsAccording to the histological study, the bone repair process developed normally regardless of the surgery technique. The process started with the appearance of granulation tissue and connective tissue cords; in the final stages, cellular differentiation, pronounced osteoblastic activity, and inter-beam formation were seen.The most active regeneration was observed in the areas where the bone defects were closed with a collagen membrane, and especially in the windows made with no perforation of the maxillary sinus membrane. The microtomographic and histological tests proved that perforation of the mucous membrane during the sinus lift operation impaired bone tissue regeneration.ConclusionThe obtained results suggest that the most promising way to close a bone defect in the anterior wall of the maxillary sinus is the use of a collagen membrane; therefore, we recommend choosing this approach for sinus lift surgery.

Modified Le Fort I interpositional grafting of the severe atrophied maxilla-a retrospective study of 106 patients over 10 years.

The objective of this study was to evaluate a modified Le Fort I interpositional grafting followed by dental implants for the rehabilitation of edentulous atrophied maxillae (Cawood classes IV and V). The surgical modification was a bilateral sinus floor augmentation prior to the osteotomy. This generated a closed recipient bed which allowed the use of particulated bone grafts (xenogenic bone mineral) and a reduced amount of autologous iliac bone grafts. A total of 106 patients with maxillary interpositional bone grafts were included in this retrospective analysis between 2006 and 2020. The panoramic radiographs and lateral cephalograms were analyzed to assess the gain and stability of the maxillary bone and the peri-implant bone loss. In addition, the observational period of up to 14years implant survival and success was evaluated. A stable vertical bone height with mean 0.63±1.41mm resorption over 5years after implant loading was observed. A mean of 0.20±0.37mm marginal bone loss was noted after 5years. The implant survival was 96.4% after 5years and implant success can be rated 91.7% in a mean follow-up period of 93months and 168months maximal observation time. Perioperative complications included sinus membrane perforation (59.43%), wound healing disturbances (25.47%), and transient primary complications (13.78%). All receded apart from two subtotal graft losses (1.8%). The modified Le Fort I osteotomy with interpositional bone grafts is a predictable procedure in terms of bone and implant stability. Patients with atrophic maxillae who are fit for surgery should be informed about risks and benefits of this treatment alternative.

Osteotomy in lateral sinus augmentation: A comparative study of rotary technique and Lateral Approach Sinus Kit®.

Various sinus lift techniques have been tried to minimize the rate of perforations, especially in Type I and Type II sinus membrane thickness. The aim and objectives of this study was to present our own experience compare and the efficacy of conventional direct sinus lift technique and direct sinus lift using LAS Kit. Our study included 14 patients in which seven patients in conventional technique and seven patients in Lateral Approach Sinus (LAS) Kit®. The results showed that the sinus membrane perforation rate, using LAS Kit® with specially designed drills, is less than that of the conventional technique, especially in Type I and II sinus membrane with the added benefit of reduced operative time. The mean operative time in conventional technique was 28.29 ± 2.21min and in LAS Kit®, it was 19.43 ± 2.88min which was statistically significantly less than the conventional technique group (P < 0.001). In both the groups, 100% implant integrity was achieved (measured using reverse torque technique) after 6 months of follow-up. It was observed that there was no statistically significant difference between the groups in pain, swelling, flap dehiscence, and infection at different time intervals. We conclude that the use of LAS Kit® for sinus lift procedure in atrophied maxilla with Type I and II sinus membrane is a much safer approach over the conventional technique. Further, the results obtained also showed that blood coagulum gave better gain in bone height over a period of 6 months.

Treatment of sinus membrane perforations during sinus lift surgeries using leukocyte and platelet-rich fibrin: A report of three cases

Schneiderian membrane (SM) perforation is the most frequent intraoperative complication during sinus lifts, which can lead to implant failure or delayed implant treatment. This article aims to show the results of using leukocyte and platelet-rich fibrin (L-PRF) in the treatment of perforations occurring during sinus lifts with a lateral window approach. Three patients (n = 5 implants) with a mean ± SD age of 57.67 ± 12.12 years were included, in whom perforations of the SM of 3-5 mm and >5 mm occurred. The mean ± SD preoperative bone height was 4.42 ± 2.96 and, at 6 months it was 9.58 ± 2.41 (P < 0.05). All implants had a 100% survival rate at 6-24 months. At the split-mouth, the mean ± SD baseline height was 5.05 ± 2.99 mm in repaired SM versus 2.92 ± 1.01 in those without any complications (P > 0.05). At 6 months, mean ± SD gains were 10.09 ± 2.44 mm versus 7.73 ± 0.90 mm, respectively, (P > 0.05). L-PRF simplifies SM repair, reducing the need for high surgical experience and/or skills. Although there are no significant differences between repaired and intact SM, at the radiological level, greater bone compactness and maturation were observed in the latter, which may be associated with the presence of air bubbles caused by anaerobic bacterial activity in repaired SM. The use of L-PRF greatly simplifies the resolution of SM perforations during sinus lift surgeries, reducing treatment times, and providing predictable results. Being of autologous origin, it accelerates and enhances healing, eliminating the possibility of autoimmune rejection reactions.

The influence of different forms of sinus membrane perforation on the prevalence of postoperative complications in lateral window sinus floor elevation: A retrospective study.

Maxillary sinus membrane perforation (SMP) during lateral window sinus floor elevation (SFE) might be associated with postoperative complications (PC). To evaluate the prevalence of PC and clinical implant outcome for different forms of SMP with lateral window SFE. The prevalence of PC such as maxillary sinusitis, graft necrosis and wound infection was retrospectively evaluated for 434 lateral window SFE (334 patients) with 331 SFE (241 patients) without and 103 SFE (93 patients) with SMP. SMP was additionally classified into four subgroups regarding to membrane perforation size (small-moderate [<10 mm] vs. large [>10 mm]) and membrane biotype ([BT] thin vs. thick). Additionally, patient- and surgery-related risk factors affecting PC and the 1-year implant survival rate were evaluated for SFE without and with SMP and subgroups. A significantly higher prevalence including significant odds ratios of PC such as maxillary sinusitis (10/103 [9.7%] vs. 4/331 [1.2%]; p < 0.021; OR: 8.85; p < 0.021) and graft necrosis (7/103[6.8%] vs. 1/103[0.3%]; p < 0.017; OR:7.43; p < 0.017) was found for SFE with than without SMP. The SMP subgroup with large size and thin BT involved significantly (p < 0.005) more PC (15/20[75%]) than all other SMP subgroups (5/20[25%]). For the risk factors evaluated the univariate analysis demonstrated differences of PC for the presence versus absence of SMP (p < 0.001) and for thin versus thick sinus mucosa (p < 0.038; p < 0.006) but not for sex, smoking, sinus septa and surgical stage. In the multivariate risk factors analysis, PC were significantly related to risk factors such as large size with thin BT (OR:18.049; p < 0.007). The 1-year implant survival rate did not differ between SFE without (99.5%) and with SMP (99.1%), regardless of successfully repaired subtype of SMP. The synopsis of perforation size and membrane biotype is crucial in differentiating different forms of SMP assessing and anticipating different prevalences of PC in lateral window SFE.

Risk factors for sinus membrane perforation during lateral window maxillary sinus floor elevation surgery: A retrospective study.

To analyze the sinus membrane perforation (SMP) rate and its potential risk factors during lateral window maxillary sinus floor elevation (LSFE). For patients with LSFEs at Department of Implantology, Stomatology Hospital, School of Medicine, Zhejiang Universitiy during January 2014 to December 2020, patient-related risk factors (age/sex/smoking habit), surgery-related risk factors (operator experiment/number of tooth units/technique of osteotomy/surgical approach), and maxillary sinus-related risk factors (residual bone height/sinus membrane thickness/lateral wall thickness/maxillary sinus contours/presence of septa/blood vessels at the lateral maxillary sinus wall) were compared between perforated and nonperforated sites and were evaluated for their influence affecting SMP. The study sample comprised 278 LSFE procedures in 278 patients; a total of 47 LSFE procedures (16.91%) presented SMP. Four significant factors were identified: smoking habit (p < 0.001), thin (≤1.5 mm) sinus membrane (p=0.027), maxillary sinus contours (p < 0.001), and presence of septa (p=0.001). The SMP rate of irregular, narrow tapered, and tapering sinus contours was significantly higher than that of ovoid and square one (p < 0.05). In general, smoking habit, thin sinus membrane, irregular, narrow tapered, and tapering sinus contours, and presence of septa may increase the risk of SMP during LSFE.

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.

Prevalence, risk factors, and repair mechanism of different forms of sinus membrane perforations in lateral window sinus lift procedure: A retrospective cohort study.

To evaluate prevalences, affecting risk factors and efforts for repair mechanism for different forms of sinus membrane perforations (SMP) during sinus floor elevation (SFE) using the lateral window technique (LWT). For 334/434 patients, SFE undergoing LWT prevalence of SMP was retrospectively evaluated including a subselection based on membrane perforation size (<10 mm: small-moderate/≥10 mm: large) and biotype (BT; thick BT/thin BT) into four subgroups (SMP1: thick BT/small-moderate; SMP2: thin BT/small-moderate; SMP3: thick BT/large; SMP4: thin BT/large). For the various subgroups, patient- and surgery-related/anatomic risk factors affecting SMP were evaluated and the scope of sinus membrane repair (SSMR) mechanisms rated with 1 (easy) to 5 (complex) was compared. For 103/434 SMP (27.6%) in 93/334 patients (30.8%) the prevalence of various forms of SMP differed significantly (p < 0.001) among the four subgroups. SMP4 with a prevalence of 45.6% (n=47) was the most frequent type, while SMP3 had low prevalence with 4.85% (n=5). Small/moderate SMPs with thick (SMP1: n=26) or thin BT (SMP2: n=23) were seen in 26.2% and 23.3%, respectively. Univariate analysis showed significant differences between subgroups with large perforations (SMP3/SMP4) and those with small/moderate perforations (SMP1/SMP2) regarding anatomic risk factors such as residual ridge height (p=0.023) and history of previous oral surgical interventions (OSI; p=0.026). Most evidently, multivariate analysis showed that induction of large SMP with thin biotype (SMP4) was significantly affected by the presence of sinus septa (p < 0.022, OR: 2.415), reduced residual ridge height (p < 0.001, OR: 1.842), and previous OSI (p < 0.001, OR: 4.545). SSMR differed significantly (p < 0.001) between SMP4 (4.62 ± 0.49) and the subgroups SMP1 (1.11 ± 0.32), SMP2 (1.08 ± 028), and SMP3 (2.2 ± 0.55). The most frequently found type of SMP had characteristics of thin biotype and large size associated with risk factors such as sinus septa, reduced residual ridge, and previous surgical interventions and required challenging repair mechanisms assessing clinical impact.

Repairing Maxillary Sinus Membrane Perforations, Iatrogenic or Intentional: Two Case Reports

Maxillary sinus augmentation is a common and predictable procedure utilized to gain vertical alveolar bone height to allow for successful placement of dental implants in the deficient posterior maxilla. The surgical techniques, however, may be associated with intraoperative complications, the most common of which is Schneiderian membrane perforation and, less commonly, bleeding and the loss of an implant into the sinus cavity. In the current report, we present two cases with unique complications. A large perforation which was discovered after the graft material had been placed was successfully managed by carefully removing the graft material from both sides of the perforation and sealing the perforation with a resorbable membrane and a tack fixation. The second case involved a patient who presented with an implant that had migrated into the sinus during an unsuccessful transcrestal sinus lift. The case was successfully treated by locating and removing the implant through an intentional membrane perforation, repairing the perforation, and placing a new implant with simultaneous grafting. Management and repair of maxillary sinus membrane perforations that are either intentionally or iatrogenically created can be predictable procedures with favorable outcomes if thoughtful evaluation and treatment are provided. Managing such complications at the time of occurrence avoids unnecessary additional surgical procedures that might prove to be even more complicated.