BACKGROUND: Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 mm. However, managing cases becomes more challenging when a maxillary sinus pseudocyst is present or when there is insufficient bone width. In this case, we utilized the bone window prepared during the lateral window sinus lift as a shell for horizontal bone augmentation. This allowed for simultaneous horizontal and vertical bone augmentation immediately after the removal of the maxillary sinus pseudocyst.
METHODS: A 28-year-old female presented to our clinic with the chief complaint of missing upper left posterior teeth. Intraoral examination showed a horizontal deficiency of the alveolar ridge contour. The height of the alveolar bone was approximately 3.6 mm on cone beam computed tomography (CBCT). And a typical well-defined \'dome-shaped\' lesion in maxillary sinus was observed on CBCT imaging. The lateral bony window was prepared using a piezo-ultrasonic device, then the bony window was fixed to the buccal side of the 26 alveolar ridge using a titanium screw with a length of 10 mm and a diameter of 1.5 mm. The space between the bony window and the alveolar ridge was filled with Bio-Oss, covered with a Bio-Gide collagen membrane, and subsequently sutured. Nine months later, the patient\'s bone width increased from 4.8 to 10.5 mm, and the bone height increased from 3.6 to 15.6 mm. Subsequently, a Straumann® 4.1 mm × 10 mm implant was placed. The final all-ceramic crown restoration was completed four months later, and both clinical and radiographic examinations showed that the implant was successful, and the patient was satisfied with the results.
CONCLUSIONS: The bone block harvested from the lateral window sinus lift can be used for simultaneous horizontal bone augmentation acting as a shell for good two-dimensional bone augmentation.

Sinus lift via the alveolar crest approach has been proven to solve inadequate alveolar bone height perfectly in the posterior region of the maxilla. Nevertheless, the surgical area cannot be directly observed, imaging methods are necessary to reveal whether the surgery has achieved the expected results. Cone-Beam Computed Tomography (CBCT) images are usually taken before surgery and at the completion of final pre-repair osseointegration and evaluate the effect of maxillary sinus lift by measuring the alveolar bone height in the bone graft area. However, there is no uniform and recognized method to accurately measure the alveolar bone height in the bone grafting area before and after maxillary sinus lift. Therefore, the authors propose a simple, accurate, and reproducible method for the measurement of alveolar bone height in maxillary sinus lift on CBCT, which will be an innovation.
30 implant cases (30 patients) were included in this study. The authors create a uniformed measurement surface in the CBCT axial interface to ensure consistency at the completion of final prerepair osseointegration and before surgery. Then changes in alveolar bone height in the bone grafting area before and after sinus lift were measured on CBCT coronal and arch planes. Finally, for the purpose of verification of repeatability, three dentists from our department were randomly selected to measure and record the above CBCT data at three different time points.
The data showed that in the CBCT measurements of the three dentists, neither the coronal plane nor the arch plane was statistically significant. (P > 0.05).
This measurement method is simple, accurate and repeatable. It can be applied to measure alveolar bone height in the bone grafting area before and after maxillary sinus lift.

OBJECTIVE: There is still debate whether intraoperative Schneiderian membrane (SM) perforation in the maxillary sinus lift causes an increase the risk of implants failure. The aim of this study was to assess an association between SM perforation and implants loss following the maxillary sinus lift.
METHODS: A systematic review and meta-analysis of clinical studies assessing association between SM perforation and implants failure based on PRISMA was conducted. Three major databases were used to gather research dating from their respective inception up until March 2018. All clinical studies expressly reported the number of the SM perforation and implants loss that installed in the perforated and nonperforated sinuses were included. The statistical analyses used were Pearson\'s correlation, simple linear regression, and meta regression. The risk ratio (RR) of implant loss between perforated and nonperforated sites was estimated.
RESULTS: A total of 2947 patients with 3884 maxillary sinuses augmentations who received 7358 implants, enrolled in 58 studies were included in this study. There was a significant relationship between the implants\' failure and SM perforation according to simple linear regression (P < .001) and meta regression analysis (P = .06). There was a significant decrease (moderate quality evidence) in implant loss in the nonperforated sinuses compared to perforated sunrises (RR = 2.17, CI: 1.52-3.10, P = .001). There was also no significant association between implant loss in the perforated sinuses and the surgical devices used (piezosurgical or rotary), surgical approach applied (lateral or crestal sinus lift), barrier membrane used and type of bone grafting materials.
CONCLUSIONS: The results of this study showed that an intraoperative SM perforation could increase the risk of implant failure after the sinus lift surgery.

OBJECTIVE: Schneiderian membrane perforation is one of the main complications during sinus augmentation. The reasons may be associated with surgical technique, septum, inadequate ridge height, and membrane thickness. However, reports that used cone-beam computed tomography (CBCT) to quantify the thickness of sinus membrane were limited. The aims of this retrospective study were: to study the correlation between membrane thickness and perforation rate during transcrestal sinus lift and to propose a classification system of sinus membrane thickness based upon CBCT data.
METHODS: One hundred and twenty-two subjects who received dental implant restorations over posterior maxilla with a total of 185 transcrestal sinus lift procedures between years 2010 to 2013 were selected consequently. Each patient selected had to have taken CBCT in the initial examination and immediately after surgery. The membrane thickness, perforation rate, residual bone height, and elevated bone height were recorded and processed for statistical analysis.
RESULTS: The mean thickness of the Schneiderian membrane was 1.78 ± 1.99 mm. There was a significant correlation between membrane thickness and perforation rate (P < 0.05), and the perforation rate was higher in thicker (≥3 mm) and thinner membrane (≤0.5 mm). Among the thickness group, Class B (between ≥1 and <2 mm) had the lowest perforation rate. No significant difference was between the perforation and the membrane morphology. A negative relationship between residual bone height and membrane thickness was found. Trend showed that in the thicker and the thinner residual bone height, the higher the perforation rate would be.
CONCLUSIONS: There was a significant correlation between membrane thickness and perforation rate. The perforation rate was lowest when the thickness was 1.5-2 mm.