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In this study, Recycled Concrete Aggregate (RCA) was employed as a sandwich technique around the geogrid to enhance the pullout resistance of the geogrid in clayey backfills. Large-scale pullout tests were conducted on three configurations: geogrid-reinforced clay, geogrid-reinforced RCA, and geogrid sandwiched between layers of RCA, aimed at investigating pullout resistance and deformation. The experiments encompassed two different geogrid types (designated as G1 and G2), varying normal pressures ranging from 10 to 50 kPa, and RCA layers with thicknesses of 40, 80, 160, and 320 mm. Results from the experiments revealed that the inclusion of RCA layers around the geogrid substantially enhanced pullout resistance, with improvements ranging from 1.5 to 3 times compared to clay specimens. Optimal RCA thicknesses were determined in order to enhance soil-geogrid bonding and pullout resistance. For G1 geogrid, a thickness of 160 mm (equivalent to replacing 25% of clay volume with RCA) was identified as optimal, while for G2 geogrid, an 80 mm thickness (equivalent to replacing 15% of clay volume with RCA) was found to be sufficient. These thicknesses were established to achieve over 80% of the pullout force compared to full RCA specimens. • Large-scale pullout tests were performed on two types of geogrids. • Recycled Concrete Aggregate (RCA) was utilized at various thicknesses within a sandwich technique to enhance geogrid pullout resistance in clayey backfills. • The optimum thickness of RCA layer in sandwich technique was determined. [ABSTRACT FROM AUTHOR]

Modern direct restorations of dental lesions with adhesive materials can be achieved through different working protocols. Among them, sandwich technique is one of the well-known procedures, especially for posterior area, in which two materials, usually glass ionomer cement and resin composite, are used together in order to obtain a monolithic dental structure, combining the properties of both materials and, thus, a superior result obtained. In this way, not only the longevity of restoration is improved, but also the tooth health and survival on dental arch are maintained. [ABSTRACT FROM AUTHOR]

Congenital abnormalities of the iliac artery are uncommon and often discovered incidentally during the diagnosis or treatment of peripheral vascular diseases such as abdominal aortic aneurysm (AAA) and peripheral arterial diseases. The endovascular treatment of infrarenal AAA can be complicated by anatomic abnormalities in the iliac arteries, such as the absence of the common iliac artery (CIA) or overly short bilateral common iliac arteries. We present a case of a patient with a ruptured AAA and bilateral absence of the CIA, successfully treated by endovascular intervention combined with preservation of the internal iliac artery using the sandwich technique.

Alveolar ridge augmentation of atrophic posterior mandibular ridge represents a challenge in oral and maxillofacial surgery to restore aesthetic and function. The aim of the study was to compare the clinical and radiographic outcomes of bone formation in atrophic posterior mandibles augmented using onlay symphysis cortico-cancellous bone block with that augmented using sandwich bone augmentation technique (Inlay). Twelve patients were selected with missing mandibular posterior teeth. CBCT were done for all patients preoperatively to assess the residual bone height, ranged between 5 and 7 mm from the inferior alveolar nerve with adequate sufficient alveolar ridge width more than 4 mm. Patients required bone augmentation procedure with autologous onlay chin graft (group I) versus those used as inlay sandwich technique (group II). Clinical and radiographic analysis were done to analyses the newly formed bone and bone height. Percent of change in bone height was also calculated and revealed that group I was higher than group II, however, statistically insignificant differences between the two groups were found regarding the percentage of newly formed bone. Vertical ridge augmentation procedures using onlay chin graft took lesser time than the interpositional grafting with fixation technique, however, both techniques are promising for vertical ridge augmentation. [ABSTRACT FROM AUTHOR]

Introduction: The current gold standard of treatment aortoiliac aneurysms are through endovascular aneurysm repairs which can result in occluding the internal iliac artery. An alternative that preserves internal iliac artery blood flow is the sandwich technique. This is when two covered stents of the internal and external iliac arteries are placed inside the main limb of common iliac artery stent. The complexity of such task is complicated by efficiently calculating the size of the stent grafts to ensure a proper fit. Methods: We have developed a mathematical proof that depends on the arterial circumferences to size the three stents needed for the sandwich technique: D≅[0.68*(d1+d2)]+2. D is the diameter of the common iliac stent, d1 and d2 is the diameter of the internal and external iliac artery stent. We added 2 mm to account for the thickness of stents. Results: We have treated 10 common iliac artery aneurysms using this formula. Patients were followed up by CTA scans three, six and twelve months after the procedure. Seven of ten had complete sealing and no type III endoleaks intraoperatively. The other three had a small, limited type III endoleak at completion angiogram, that disappeared completely on the three months follow-up. At one-year follow up only one patient developed moderate claudication and erectile dysfunction. Conclusion: ST is considered a practical and feasible approach, as it is easy to implement and can be utilized in most cases, especially in emergencies. It is also cost effective due the use of standard grafts without the need for specialized stents. Our aiming by improving this surgical technique is that we will be able to help standardize practice leading to reduced waste, maintain longer-term repair and therefore reduce complication risks.

Background: Giant Cell Tumor (GCT) of the distal tibia of immature skeleton is a very uncommon occurrence, with very few reports available in literature depicting its course, treatment or complications in immature skeleton. Neoadjuvant Zolendronate holds good promise in the treatment of GCT, decreasing the tumor size and increasing peripheral mineralization, which helps in definitive surgery. Sandwich technique is a novel method of treatment of GCT utilized for subchondral GCTs in distal femur, but there is no report regarding its use for distal tibia. Case report: We present a case of 14 years old adolescent girl who complained of pain, swelling and difficulty in weight bearing of right ankle since 4 months. Diagnosis confirmed it to be GCT of distal tibia. The child was treated with neoadjuvant Zolendronate and Sandwich technique of treatment for the GCT which showed excellent result with no recurrence at a follow-up of 2 years. Conclusion: GCT of distal tibia in immature skeleton although very rare, but can be a possibility. It can be effectively treated using neoadjuvant Zolendronate and Sandwich technique with very favorable clinical and oncological result.

Introduction: Lateral abdominal wall hernias are rare defects but and few studies show support towards a standard protocol for repair; sandwich technique or double prosthetic repair is a possible technique. Case report: Describe step by step the double prosthetic repair, by implementing an intermuscular and preper-itoneal mesh repair. Placement of a mesh in preperitoneal and intermuscular area, attached to a bony landmark and transparietal knots. Conclusions: The double prosthetic repair technique is effective for lumbar eventrations, even though we are still missing evidence to determine which of its three variables is ideal. [ABSTRACT FROM AUTHOR]

Background Giant cell tumor (GCT) of bone is a benign locally aggressive tumor that constitutes 20% of the body's benign bone tumors. Most of the GCTs exhibit a typical epiphyseal location that shows a tendency for significant bone destruction and local recurrence. We aimed to assess the functional and oncological outcomes of GCT patients treated with bone grafting and cementation with or without gel foam.Materials and methods This prospective study included 40 patients presented at El Hadara University Hospital with GCT of bone around the knee from January 2017 to January 2022 treated by bone graft and cementation. Twenty cases were treated with gel foam (Group I) and 20 cases were treated without gel foam (Group II) through random allocation without selection. Recurrence was assessed as progressive lysis of 5 mm at the bone cement interface. Functional outcomes were assessed using the musculoskeletal tumor society score (MSTS) after a period of minimum 30 months.Results In Group I, 18 patients (90%) had excellent results (range 24 and 30) according to MSTS and two patients (10%) had good results (range 18 and 23), while in Group II, 16 patients (80%) had excellent results and four patients (20%) had good results. No patients were graded as having fair or poor results. Twenty patients (100%) had satisfactory results, and no patients (0%) had unsatisfactory results. The overall recurrence rate was about 15%.Conclusion Reconstruction of GCT of bone with sandwich technique offers good option as joint preserving surgery. Most of the patients get benefit in terms of better quality of life and good function regardless of age and gender. Subchondral bone grafting reduces the effect of heat on articular cartilage, but longer follow-up is required. There is no benefit of gel foam addition in terms of function or oncological outcome.

Introduction: Surgical treatment of medium and large sized nasal septal perforation is challenging. Techniques with and without interposition grafts are used. Objective: The aim of this study is to explain how we apply the sandwich graft technique that we use in medium and large nasal septal perforations as well as to present the results. Methods: We retrospectively reviewed the patients who were operated with the sandwich graft technique between January 2014 to December 2018 and followed up for at least 6 months. The demographic data, symptom scores, examination, and surgical findings of the patients were taken from the hospital records. Surgical outcomes were presented according to both perforation etiologies (idiopathic or iatrogenic) and sizes (Group A: < 2 cm, Group B: ≥ 2 cm). Results: We reviewed 52 cases and 56 surgeries. The average diameter of the perforations was 19.2 mm. The success rate after initial surgeries was 84.6% (44/52). After 4 revision surgeries, the perforation was closed in 88.5% of the cases (46/52). Success rates for Group A and Group B were 90.0% and 86.4%, respectively (p = 0.689). The success rates in idiopathic and iatrogenic cases were 93.3% and 86.5%, respectively (p = 0.659). Conclusion: This study showed that the success rate of sandwich graft technique was higher in medium-sized perforations than large-sized ones and in idiopathic perforations compared to iatrogenic ones, but the latter rate was not statistically significant. This demonstrated that perforation size was not as important in the sandwich graft technique as in flap techniques.

INTRODUCTION: Endovascular reconstruction of the thoracoabdominal aorta is highly complex due to the need to preserve the main visceral branches. Optimal treatment with fenestrated and branched aneurysm aortic repair (F/B-EVAR) is usually not possible in urgent situations. Parallel grafting technique as an “off-the-shelf” solution have been described with good short and medium-term results. CASE REPORT: A 44-year-old male, born in Guinea Bissau, presents to the emergency department with epigastric pain radiating to the dorsum. The patient had a history of large vessel vasculitis secondary to Bechet’s disease (HLA B51 allele positivity) and previous thoracic aneurysm aortic repair (TEVAR) to treat a paraceliac aortic pseudoaneurysm. Computed tomography angiography (CTA) demonstrated a pseudoaneurysm with approximately 10 cm diameter at zone 6 immediately distal to the previous endoprosthesis. The pseudoaneurysm was excluded with a parallel grafting technique using a 31mm aortic endoprosthesis with a periscope graft for the right renal artery in a “sandwich-like” configuration and a chimney graft for the superior mesenteric artery (SMA). Postoperative CTA confirmed the exclusion of the pseudoaneurysm and permeable bridging stents. CONCLUSION: The pathology of the thoracoabdominal aorta is technically demanding, requiring experience and detailed planning. The complexity increases in emergency cases. Our case highlights that the parallel grafting technique should be encouraged in life-threatening scenarios as a readily available solution for complex aortic repair, even in a reconstructed aorta.

Background: Impaction of morselized allograft is an appealing procedure for addressing the bone defects. However, concerns remain about its suitability for massive defects. We used a novel “sandwich” technique by impacting the morselized allograft in layers with an intervening layer of injectable bone graft substitute for restoring bone defects during acetabular reconstruction in total hip arthroplasties. Methods: From August 2015 to June 2017, 17 revisions, 4 rerevisions, and 3 complex primary total hip arthroplasties were operated by this novel technique. Postoperatively, serial X-rays were evaluated at regular intervals. Clinical and functional outcomes were assessed by the Harris hip score. To examine if introducing an injectable bone substitute into allograft stock increased its load-bearing capability, simulated mechanical testing using Synbone samples was conducted in the laboratory. Results: The mean Harris hip score significantly improved from 54.6 preoperatively to 86.8 at the latest follow-up. Graft incorporation was seen in all the cases. There was no evidence of component migration or loosening as compared to the X-rays at 3 weeks and 3 months in all the cases. With revision of component as end point, the survivorship was 100% at 82 months. The mechanical testing reported a higher capability of allograft samples when compared to those without bone substitutes. Conclusions: Our data confirms that the use of the “sandwich” technique is a reliable option for major acetabular reconstruction. Early weight bearing is a significant value addition, and short-term results confirm good clinical and functional outcome. Longer follow-up is necessary to assess the status of the construct in the long term.

Giant cell tumor (GCT) of bone is a benign locally aggressive tumor that constitutes 20% of the body's benign bone tumors. Most of the GCTs exhibit a typical epiphyseal location that shows a tendency for significant bone destruction and local recurrence. We aimed to assess the functional and oncological outcomes of GCT patients treated with bone grafting and cementation with or without gel foam. This prospective study included 40 patients presented at El Hadara University Hospital with GCT of bone around the knee from January 2017 to January 2022 treated by bone graft and cementation. Twenty cases were treated with gel foam (Group I) and 20 cases were treated without gel foam (Group II) through random allocation without selection. Recurrence was assessed as progressive lysis of 5 mm at the bone cement interface. Functional outcomes were assessed using the musculoskeletal tumor society score (MSTS) after a period of minimum 30 months. In Group I, 18 patients (90%) had excellent results (range 24 and 30) according to MSTS and two patients (10%) had good results (range 18 and 23), while in Group II, 16 patients (80%) had excellent results and four patients (20%) had good results. No patients were graded as having fair or poor results. Twenty patients (100%) had satisfactory results, and no patients (0%) had unsatisfactory results. The overall recurrence rate was about 15%. Reconstruction of GCT of bone with sandwich technique offers good option as joint preserving surgery. Most of the patients get benefit in terms of better quality of life and good function regardless of age and gender. Subchondral bone grafting reduces the effect of heat on articular cartilage, but longer follow-up is required. There is no benefit of gel foam addition in terms of function or oncological outcome. [ABSTRACT FROM AUTHOR]

Objectives: The Iliac Sandwich is an off-label technique that uses parallel stent grafts to treat aortoiliac aneurysms. The purpose of this experimental study is to evaluate the conformability and juxtaposition of stent grafts combinations used in this technique through in-vitro mechanical evaluation, computed tomography (CT) analyses, and a controlled pulsatile flow system. Methods: The combinations of two Viabahn® ("V-V") or Viabahn® and Excluder® iliac extension ("V-E") were analysed using CT imaging with measurement of the gutter area by two independent analysts before and after balloon angioplasty. In a second phase, the parallel stent combinations were also evaluated using CT imaging after being implanted in the aortic aneurysm model with a pulsatile flow system with controlled temperature, viscosity, and density. Results: The "V-E" group had a better conformability when compared to the "V-V" group, ensuring smaller gutter areas (0.0064 cm2 ± 0.01 vs. 0.0228 cm2 ± 0.03, p < 0.001). Post dilatation with two non-compliant balloons resulted in enlargement of the gutter area (Area A, p 0.065; Area B, p 0.071). Conversely, post dilatation with a non-compliant balloon for the internal iliac component and a compliant balloon for the external iliac device reduced the gutter area (Area A, p 0.008; Area B, p 0.010). Conclusion: The combination of Viabahn® and Excluder® iliac extension device ("V-E") had a smaller gutter area compared to two Viabahn® parallel stents for the Iliac Sandwich Technique. Post dilatation using a non-compliant balloon for the internal iliac device and a compliant balloon for the external iliac provided superior conformability and juxtaposition. [ABSTRACT FROM AUTHOR]

IntroductionAutologous chondrocyte implantation (ACI) is a crucial method for the treatment of defects in articular cartilage. However, the extant methods for the preparation of autologous chondrocyte patch are relatively complicated and money-consuming. Therefore, an efficient, reliable, easy-to-follow, and cost-effective technique is needed to overcome constraints. This case report aims to introduce an autologous chondrocyte patch fabrication technique to repair knee joint cartilage defects and report our typical cases with a 2-year follow-up.Case presentationWe described four cases in which patients complained of knee joint pain. According to radiological examination, the patients were diagnosed as knee joint cartilage defect. Arthroscopy and autologous chondrocyte patch implantation were performed as well as a 2-year follow up of patients. The autologous chondrocyte patch for knee joint cartilage repair was fabricated using a “sandwich” technique. The preoperative and postoperative knee function was evaluated by four subjective evaluation systems. MRI was performed for all patients to achieve more intuitionistic observation of the postoperative radiological changes of defect sites. The quality of repaired tissue was evaluated by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART). Postoperative follow-up showed improvement in clinical and MOCART scores for all patients. However, one patient complained of knee joint pain after walking for a long time or recreational activities from 12- to 18-month postoperatively. The location of pain for this patient was not in accordance with the location of cartilage defect.ConclusionThe patients undergoing autologous chondrocyte patch implantation demonstrated clinical improvement and good quality of repaired tissue postoperatively. The procedure is an efficient and cost-effective treatment for knee joint cartilage defect in this report. In addition, patients with osteoarthritis carry the risk of a poor outcome after the procedure, and whether to have a procedure should be considered carefully.

The success of dental restorations depends mainly on the ability to bond to other filling materials and tooth substances, in order to resist the multitude of forces acting on the bond within the oral cavity. Although the shortcomings of composite resins have been significantly reduced over the past three decades, microleakage due to shrinkage under masticatory loads is unavoidable. In order to overcome such problems, two materials laminated with matched properties can be used to achieve optimum results. The sandwich technique is an approach in which dentine is replaced by glass ionomer cement (GIC), and enamel is replaced by composite resin. In the past, numerous materials have been proposed with adequate properties to be used in this manner, but the results are conflicting in terms of bonding to the various forms of GIC, and the appearance of microcracks or gap formation during functional loading. This study aimed to evaluate the shear bond strength (SBS) and mode of failure between the following core materials: composite resins (CR) (Methacrylate Z350™, Ceram X™, and Spectrum™) with a base material of glass ionomer cement (GIC, Ketac Molar™). Eight samples were made with the help of polytetrafluoroethylene sheets (TEFLON, Wilmington, DE, USA). Each sheet consisted of holes which were 4 mm in diameter and 2 mm in thickness. The combination of materials was sandwiched. The samples were stored in distilled water and then placed in an incubator for 24 h in order to ensure complete polymerization. The samples were thermocycled for 500 cycles between 5–55 °C/ 30 s. Following thermocycling, SBS testing was performed using a universal testing machine. Additionally, scanning electron microscopy (SEM) was performed on representative samples for the bond failure analysis between GIC and the composite resins. The Ceram-X™ nanocomposite showed significantly higher bond strength than Methacrylate Z350™ or Spectrum™ (p = 0.002). The Methacrylate Z350™ and the Spectrum™ composite specimens demonstrated a similar SBS (p = 0.281). The SBS of the Ceram X™ to GIC was the highest compared to Methacrylate Z350™ and Spectrum™. Therefore Ceram X™ may produce a better bond with GIC, and may protect teeth against recurrent caries and failure of the restoration. Methacrylate Z350™ is comparable to Spectrum™ CR and can be used as an alternative. A combination of adhesive and mixed failure was observed in Methacrylate Z350™ CR and GIC, while adhesive failure was predominantly found in both Ceram X™ and Spectrum™ with GIC restorations. [ABSTRACT FROM AUTHOR]

Labyrinthine fistula is the most common complication of middle ear cholesteatoma. To explore the postoperative hearing changes and surgical results of repairing middle ear cholesteatoma with labyrinthine fistula using the 'sandwich technique'. We retrospectively studied the clinical data of 36 patients (36 ears) who underwent surgical treatment for cholesteatoma with labyrinthine fistula. All patients were treated by completely removing the cholesteatoma matrix and repairing the fistula using the 'sandwich technique'. The hearing, clinical features, radiological data, intraoperative findings, and surgical results were respectively analyzed. Most labyrinthine fistulas were located in the lateral semicircular canal (94%). Fifty percent of fistulas were of medium size. Based on Dornhoffer classification, 17 cases of labyrinthine fistulas were classified as I. In 34 patients, the average bone conduction threshold improved or did not change after surgery. Two patients had preoperative facial paralysis. During follow-up (3–60 months), all patients had no postoperative vertigo symptoms and disease recurrence. Following the removal of the cholesteatoma matrix, the fistula is repaired using the "sandwich technique", which preserves or increases hearing and achieves an anti-vertiginous effect. This finding suggests that, 'sandwich technique' is a feasible procedure to treat cholesteatoma with labyrinthine fistula. [ABSTRACT FROM AUTHOR]

Abstract Background Different techniques have been described to repair post myocardial infarction ventricular septal rupture (VSR), each method may result in residual shunting, bleeding, and suboptimal left ventricular (LV) performance secondary to change in LV geometry. The aim of this report is to describe early and mid-term results of sandwich technique through right ventricle in five consecutive patients. Case presentation Five consecutive patients (3 women and 2 men) with VSR (mean age 62.8 years, range 51-70) underwent surgical repair for postinfarction ventricular septal rupture by sandwich technique performed through right ventricle from August 2012 to April 2019 in our institute. Reconstruction of the septum was performed by two patches of 0.6 mm Gore-Tex on each side of the septal defect through right ventricular incision, according to the method described by Isoda et al. Coronary artery bypass grafting was performed in two patients. The mean aortic clamp time was 90 min (range, 64 to 157 min). The mean extracorporeal circulation time was 146.6 min (range, 108 to 240 min). Postoperative intensive care unit (ICU) stay averaged 12 days (range, 4-40 days). There was no hospital mortality. No postoperative residual shunting was detected, and no patient needed re-operation for bleeding. Patients have been followed up for a mean of 24.4 months (range, 1 week to 7 years). There was one death seven days after discharge due to arrhythmia (40 days after surgery). Conclusion Sandwich technique through right ventricular approach is simple and extendable to all VSRs irrespective of their locations. Residual shunting and bleeding are negligible or zero. It may be considered as standard of repair for patient with post infarction ventricular septal rupture.

Objective: To evaluate the mid-term outcomes of different treatment strategies for the internal iliac artery (IIA) during EVAR., Methods: This was a retrospective study. All patients undergoing EVAR, who required treatment of at least one side of IIA from January 2013 to July 2022 in a single center, were included. According to the different treatment strategies for IIA, the patients were divided into UP (unilateral preservation), BP (bilateral preservation) and BE (bilateral embolization) groups. The primary outcomes included buttock claudication, bowel ischemia and iliac-related reintervention. Then patients who underwent IIA reconstruction were divided into IPG (iliac parallel stent graft) and IBG (iliac branch stent graft) groups according to the reconstruction technique. The primary outcomes included endoleak, iliac branch occlusion and iliac-related reintervention., Results: A total of 237 patients were included, including 167 in the UP group, 9 in the BP group and 61 in the BE group. The mean follow-up time was 39.0 ± 27.7, 50.0 ± 22.1 and 25.8 ± 18.9 months in UP, BP and BE groups, respectively. Thirty cases (12.7%) of buttock claudication occurred, and it was significantly higher in the BE group than the UP group (26.2% vs. 7.8%, p  < 0.001). There were no significant differences in the other follow-up outcomes among three groups. The K-M analysis indicated that the patients in the BE group had a lower survival rate than those in the other two groups (p = 0.024). 24 patients underwent IIA reconstruction, including 8 in the IPG group and 16 in the IBG group. The endoleak in the IBG group was significantly lower than that in the IPG group (0% vs. 25.0%, p  = 0.041). The iliac-related reintervention, iliac occlusion and mortality were similar between the two groups., Conclusion: Overall it is beneficial for patients to preserve at least one side of IIA during EVAR as much as possible. Compared with IPG, IBG might be more applicable for IIA reconstruction.

In this article, we introduce a modified technique of minor ipsilateral simple limbal epithelial transplantation (mini-SLET) in pediatric patients of limbal stem cell deficiency (LSCD). Two children with unilateral partial LSCD underwent the innovative technique of mini-SLET, where harvested limbal tissues were placed over the raw cornea and were covered with amniotic membrane. Both patients were followed till 9 months. Both cases showed favorable outcome and uneventful recovery. Results were comparable with the classical technique. This innovative modification of mini-SLET is safe, feasible, and an effective alternative with favorable visual outcome especially in pediatric population. It can be a breakthrough for LSCD management in developing countries with limited resources.

The study aimed to introduce a perspective of the essential reason behind why marginal microleakage develops regardless of the composite type, the technique, or the bonding system applied, especially in gingival floor of class II cavities. Materials and Methods: Three types of composite resin materials (CharmfilTM, ParaFillTM, and ProMedica®) were used to evaluate microleakage of class II restorations using two restorative approaches. Twenty four newly extracted bicuspid teeth were divided into two main groups (n=12 each) according to the restoration technique (open or closed sandwich techniques). Teeth of each group were then divided into 3 groups (n= 4 each) according to the type of the composite resin used. The restorations were then subjected to a thermocycling process and then were immersed into methylene blue solution for 12 hours. Mesiodistal sectional cuts were made along the central grooves and assessed under stereomicroscope for marginal microleakage. The data were statistically analyzed with a p-value 0.05). Under the microscope, the marginal microleakage was more obvious at the cervical region than at the occlusal region. Conclusion: There was no effect of the composite type or the application technique used on the occurrence of marginal microleakage. The first portion of the material applied against the cavity floor is the primary factor involved in possibly minimizing marginal microleakage.

The success of dental restorations depends mainly on the ability to bond to other filling materials and tooth substances, in order to resist the multitude of forces acting on the bond within the oral cavity. Although the shortcomings of composite resins have been significantly reduced over the past three decades, microleakage due to shrinkage under masticatory loads is unavoidable. In order to overcome such problems, two materials laminated with matched properties can be used to achieve optimum results. The sandwich technique is an approach in which dentine is replaced by glass ionomer cement (GIC), and enamel is replaced by composite resin. In the past, numerous materials have been proposed with adequate properties to be used in this manner, but the results are conflicting in terms of bonding to the various forms of GIC, and the appearance of microcracks or gap formation during functional loading. This study aimed to evaluate the shear bond strength (SBS) and mode of failure between the following core materials: composite resins (CR) (Methacrylate Z350™, Ceram X™, and Spectrum™) with a base material of glass ionomer cement (GIC, Ketac Molar™). Eight samples were made with the help of polytetrafluoroethylene sheets (TEFLON, Wilmington, DE, USA). Each sheet consisted of holes which were 4 mm in diameter and 2 mm in thickness. The combination of materials was sandwiched. The samples were stored in distilled water and then placed in an incubator for 24 h in order to ensure complete polymerization. The samples were thermocycled for 500 cycles between 5–55 °C/ 30 s. Following thermocycling, SBS testing was performed using a universal testing machine. Additionally, scanning electron microscopy (SEM) was performed on representative samples for the bond failure analysis between GIC and the composite resins. The Ceram-X™ nanocomposite showed significantly higher bond strength than Methacrylate Z350™ or Spectrum™ (p = 0.002). The Methacrylate Z350™ and the Spectrum™ composite specimens demonstrated a similar SBS (p = 0.281). The SBS of the Ceram X™ to GIC was the highest compared to Methacrylate Z350™ and Spectrum™. Therefore Ceram X™ may produce a better bond with GIC, and may protect teeth against recurrent caries and failure of the restoration. Methacrylate Z350™ is comparable to Spectrum™ CR and can be used as an alternative. A combination of adhesive and mixed failure was observed in Methacrylate Z350™ CR and GIC, while adhesive failure was predominantly found in both Ceram X™ and Spectrum™ with GIC restorations.

Background: Nearly 50% of patients with an ostomy will develop a parastomal hernia (PSH). Its repair remains a surgical challenge. Both laparoscopic "modified Sugarbaker" (SB) and Keyhole (KH) repair are currently in use, frequently with unsatisfactory results."Sandwich Repair" (SR) may be an alternative to reduce recurrence rates. We present the change of our technique from KH to SR. Methods: We collected data from all consecutive laparoscopic PSH repairs at our institution from 2004 until now (from 2004 to 2013 treated with KH, from 2014 with SR) and compared the results of the two groups. Primary endpoint was recurrence rate at 1 year. Secondary outcomes were operative time, PO length of hospital stay (LOS), and short and long-term complications. Results: 13 patients underwent SR. Main changes in surgical technique concerned primary defect closure, no stay sutures, use of glue for first mesh fixation, and partial lateral covering of the underlying mesh with a peritoneal flap. Early postoperative course after SR was uneventful and no recurrence at 1 year was recorded. In the KH group (19 patients), short-term complications occurred in two cases (10%), with one parietal hematoma and one case of intensive pain; we had four recurrences at 1 year (21%). LOS was shorter in the SR group (mean 4 days vs 6, p = 0.004). The KH group had 2 (10%) occurrences of chronic seroma and one bowel perforation (5%), while the SR group had one (8%) occurrence of chronic pain. Median follow-up was 26 months (range 13–78) for the SR group and 47 months (12–105) for the KH group. Conclusion: SR is safe and effective in expert hands and provides promising preliminary results. [ABSTRACT FROM AUTHOR]

Objective: The treatment of femoral nonunion is challenging for both the surgeon and the patient. Strut allografts increase the bone stock, enhance fracture healing and increase stability by acting as a biological plate. In this study, we aimed to report the results of the sandwich technique with two-strut allograft in the treatment of oligotrophic or atrophic femoral nonunions. Methods: Medical records of the patients who were treated due to femoral nonunion in a single centre were retrospectively reviewed. Twenty-one patients (10 males, 11 females) with a mean age of 49 (range: 21 to 79) years were included in the study. The left side was affected in 11 patients, whereas the right side was affected in ten. The patients had 11 femoral shaft fractures, seven proximal femoral fractures and three distal femoral fractures. The mean time from the previous operation to the nonunion surgery was 9.6 (range: 6 to 22) months. Results: Union was achieved in all patients after a mean period of 6.2 (range: 4 to 10) months. The mean follow-up time was 46.8 (range: 12 to 86) months. One patient had superficial surgical site infection in the autologous graft donor site. Conclusion: The sandwich technique with two-strut allograft provides good results in the treatment of femoral nonunion. The technique can be used on any type of nonunion, at any segment of the femur and can be combined with different fixation techniques. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study is to analyze our single-center experience in endovascular treatment of splenic artery aneurysms (SAAs) with transcatheter coil embolization, comparing long-term outcomes of packing and sandwich techniques., Materials and Methods: Between January 2010 and December 2021, 28 patients with certain diagnosis of non-ruptured asymptomatic SAA were treated with 2 different embolization techniques (packing, n=10, and sandwich, n=18). Early outcomes assessed were technical success, overall mortality, mean hospital stay, post-embolization syndrome rate, and freedom from splenectomy rate. Estimated 5-year outcomes in terms of freedom from sac reperfusion, and freedom from reintervention were evaluated and compared between the 2 different embolization techniques., Results: The mean SAA diameter was 2.8±0.8 cm. Overall technical success rate was 100%. Intraoperative and 30-day mortality rates were 0 in both groups. One patient in the sandwich group required a postoperative splenectomy. The mean follow-up period was 58.3±44.5 months. Estimated overall 5-year survival was 86.7%. Five-year freedom from sac reperfusion was 100% in the sandwich group, and 85.7% in the packing group, with no difference between the 2 groups (p=0.131), whereas freedom from reintervention was 100% in the sandwich group, and 75% in the packing group with a statistically significant difference (p=0.049; log-rank=3.750)., Conclusions: Embolization of SAAs seemed to be safe and effective with 100% of technical success rate and good perioperative results. Both sandwich and packing techniques yielded promising results also in the long-term period., Clinical Impact: Transcatheter coil embolization of splenic artery aneurysms seems to be a safe and effective procedure with a 100% technical success and satisfactory perioperative outcomes. Sandwich and packing techniques offer good results in the long-term period. Freedom from reintervention seems to be optimal and comparable between the 2 techniques., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: Open repair is still the first choice for thoraco-abdominal and para-renal aortic aneurysms, but surgical treatment is burdened by significant morbidity and mortality, especially in urgent setting. Endovascular treatment by fenestrated or branched endografts is feasible and safe; but in urgent/emergent settings, custom-made endografts are hardly available in due time, and the repair with standard multibranched devices is still debated in cases with complex anatomy. Parallel grafting, on the other hand, which exploits covered stents to preserve patency of the visceral vessels, has been shown as a valuable option and can be performed in urgency, though some concerns still remain regarding its durability and complications. The purpose of this case series is to review the outcomes of all consecutive cases of complex aortic diseases treated with this technique in emergent/urgent setting. Materials and methods: All cases of endovascular aortic repair of thoraco-abdominal and para-thoraco-abdominal performed in urgency or emergency from 2016 to June 2019 were retrospectively reviewed, recording clinical records, operative technique, primary technical success, and long-term outcomes. Each patient was followed-up by computed tomography angiography three months after the procedure and yearly thereafter. Results: Twenty consecutive patients (median age: 68, range: 47–89, male/female ratio: 16:4) affected by para-thoraco-abdominal (12) or thoraco-abdominal (8) were treated in urgent or emergent setting by chimney and/or periscope technique. A total number of 37 visceral vessels were stented (29 renal arteries, 1 polar artery of the kidney, 3 superior mesenteric arteries, and 4 coeliac trunks). Primary technical success was 100%, with one perioperative death. One patient died on post-operative month III for unrelated cause. Two type II endoleaks were detected at the first post-operative imaging studies and were managed conservatively. One type IB endoleak was treated by endovascular repair with a custom-made endograft (overall re-intervention rate: 5%). Over a median 22 months follow-up (range: 4–40, interquartile range: 12 months), all stentgrafts were patent. Conclusion: Parallel graft is a feasible and safe option that should be considered in urgent and emergent treatment of para-thoraco-abdominal and thoraco-abdominal, when fenestrated and branched endografts cannot be used. [ABSTRACT FROM AUTHOR]

Bite force measurement is an important parameter when checking the function and integrity of the masticatory system, whereas it is currently very difficult to measure bite force during functional movement. Hence, the purpose of this study is to explore the potential technique and device for the measurement and intervention of the continuous bite forces on functional and dynamic occlusal condition. A portable biosensor by sandwich technique was designed, and the validity, reliability, and sensitivity were determined by mechanical pressure loading tests; meanwhile, the pressure signal is acquired by, and transmitted to, voltage changes by the electrical measurements of the sensors. The result is that, when the mechanical stress detection device is thicker than 3.5 mm, it shows relatively ideal mechanical properties; however, when the thickness is less than 3.0 mm, there is a risk of cracking. Mechanical stress changing and voltage variation had a regularity and positive relationship in this study. The mechanical stress-measuring device made by medical and industrial cross has a good application prospect for the measurement of bite force during function.

Objective  There is a direct fistulous connection between the cavernous segment of the internal carotid artery and cavernous sinus in cases of direct carotid–cavernous fistula (CCF). Endovascular embolization is the mainstay of management in this condition. This study is about the evolution of endovascular treatment methods and the development of a cost-effective technique for embolization of direct CCF at a tertiary care center. Materials and Methods  A retrospective analysis was performed of all the cases of direct type CCF embolized by endovascular techniques in our department from 2008 to 2018.Clinical follow-up of these patients was done at 1 week, 3 months, and 6 months. Results  A total of 45 patients with 40 having a prior history of head trauma were included in this study. All cases were treated with a transarterial route except one which was treated with the transvenous approach. Detachable balloon s were used in 12 (26.67%) patients, only detachable coils in 14 cases (31.11%), both detachable balloons and coils in 9 cases (20%), and both detachable and push coils, that is, sandwich technique in 8 cases (17.78%). Parent arterial occlusion was performed in 10 patients (22.22%). There was complete resolution of chemosis and bruit in all the patients. Conclusion  Endovascular treatment is the mainstay of management in direct CCF. Using more fibered thrombogenic coils in a sandwich manner decreases the cost of the treatment significantly. [ABSTRACT FROM AUTHOR]

The sandwich or laminate technique is recommended method for resin composite restorations. The bond between GIC or RMGIC and dental composite is main factor affecting retention, sealing and durability of the sandwich restorations. This laboratory based experimental study compared and evaluated shear bond strength of composite resin bonded to conventional GICs and RMGICs using simple etch & rinse technique and with or without total etch adhesive. The shear strength of conventional GICs (Fuji IX and Chemfil rock) and RMGICs (Fuji Plus and Fuji II LC) bonded to dental composite was investigated at 4 weeks. Thirty discs (10mm diameter x 2mm height) for each conventional GIC and RMGIC were fabricated by using polyvinyl siloxane (PVS) moulds. The discs of Fuji IX, Chemfil Rock and Fuji plus were self-cured (15 minutes) whereas discs of Fuji II LC were light cured (20 sec). These discs were inserted into cold cure acrylic resin in PVS moulds to form acrylic blocks. These blocks were wrapped in moist paper and put in 100 % humidified bags for 4 weeks at 37 °C. Total 120 cylinders of composites having diameter of 7mm and height of 5mm were prepared. The surfaces of GICs and RMGICs discs were initially treated with or without acid etching and acid etching plus adhesive before placement of composite cylinders. Shear bond strength of each sample was measured after 4 weeks via Instron machine (M 30 K) at 0.5mm/ min speed and load of 1 KN was used to fracture the sample. Means and standard deviations were calculated and t-test was used to analyse statistical differences. Higher shear bond strength values for RMGICs with acid etchant plus bonding agent were observed as compared to GICs whereas GICs showed higher shear bond strength values with acid etchant alone. While RMGIC (Fuji II LC) showed low value with acid etchant alone and highest with the addition of bonding agent. But Fuji Plus showed a high value than both GICs with acid etchant alone. The conclusion was that RMGICs bonded to composite with the use of both acid etchant and bonding adhesive had greater values of shear strength than GICs. While, GICs had higher bond strength values with acid etching only than Fuji II LC. [ABSTRACT FROM AUTHOR]

Objective: The treatment of femoral nonunion is challenging for both the surgeon and the patient. Strut allografts increase the bone stock, enhance fracture healing and increase stability by acting as a biological plate. In this study, we aimed to report the results of the sandwich technique with two-strut allograft in the treatment of oligotrophic or atrophic femoral nonunions.Methods: Medical records of the patients who were treated due to femoral nonunion in a single center were retrospectively reviewed. Twenty-one patients (10 males, 11 females) with a mean age of 49 (range: 21 to 79) years were included in the study. The left side was affected in 11 patients, whereas the right side was affected in ten. The patients had 11 femoral shaft fractures, seven proximal femoral fractures and three distal femoral fractures. The mean time from the previous operation to the nonunion surgery was 9.6 (range: 6 to 22) months.Results: Union was achieved in all patients after a mean period of 6.2 (range: 4 to 10) months. The mean follow-up time was 46.8 (range: 12 to 86) months. One patient had superficial surgical site infection in the autologous graft donor site.Conclusion: The sandwich technique with two-strut allograft provides good results in the treatment of femoral nonunion. The technique can be used on any type of nonunion, at any segment of the femur and can be combined with different fixation techniques. [ABSTRACT FROM AUTHOR]

Background: Different techniques have been described to repair post myocardial infarction ventricular septal rupture (VSR), each method may result in residual shunting, bleeding, and suboptimal left ventricular (LV) performance secondary to change in LV geometry. The aim of this report is to describe early and mid-term results of sandwich technique through right ventricle in five consecutive patients. Case presentation: Five consecutive patients (3 women and 2 men) with VSR (mean age 62.8 years, range 51-70) underwent surgical repair for postinfarction ventricular septal rupture by sandwich technique performed through right ventricle from August 2012 to April 2019 in our institute. Reconstruction of the septum was performed by two patches of 0.6 mm Gore-Tex on each side of the septal defect through right ventricular incision, according to the method described by Isoda et al. Coronary artery bypass grafting was performed in two patients. The mean aortic clamp time was 90 min (range, 64 to 157 min). The mean extracorporeal circulation time was 146.6 min (range, 108 to 240 min). Postoperative intensive care unit (ICU) stay averaged 12 days (range, 4-40 days). There was no hospital mortality. No postoperative residual shunting was detected, and no patient needed re-operation for bleeding. Patients have been followed up for a mean of 24.4 months (range, 1 week to 7 years). There was one death seven days after discharge due to arrhythmia (40 days after surgery). Conclusion: Sandwich technique through right ventricular approach is simple and extendable to all VSRs irrespective of their locations. Residual shunting and bleeding are negligible or zero. It may be considered as standard of repair for patient with post infarction ventricular septal rupture. [ABSTRACT FROM AUTHOR]

Background: Acquired ventricular septal defect (VSD) is a life‐threatening condition that occurred after a myocardial infarction (MI). The timing of the intervention remains very debated but it is crucial to choose the right surgical technique to obtain a stable and complete repair. Methods: We report the case of an acquired VSD that occurred after a MI without obstructions of coronary arteries (MINOCA). The defect was promptly treated with a double patch plus glue sandwich technique. Results: At the end of the procedure, echocardiographic data showed no residual shunt, and no major adverse cardiac and cerebrovascular events were reported during postoperative days or 6 months follow‐up. Conclusion: Our report suggests that MI's mechanical complications can occur even after a MINOCA. [ABSTRACT FROM AUTHOR]

In this article, we introduce a modified technique of minor ipsilateral simple limbal epithelial transplantation (mini-SLET) in pediatric patients of limbal stem cell deficiency (LSCD). Two children with unilateral partial LSCD underwent the innovative technique of mini-SLET, where harvested limbal tissues were placed over the raw cornea and were covered with amniotic membrane. Both patients were followed till 9 months. Both cases showed favorable outcome and uneventful recovery. Results were comparable with the classical technique. This innovative modification of mini-SLET is safe, feasible, and an effective alternative with favorable visual outcome especially in pediatric population. It can be a breakthrough for LSCD management in developing countries with limited resources. [ABSTRACT FROM AUTHOR]

We report a novel surgical sandwich technique using a combination of intraocular perfluoropropane (C3F8) and silicone oil for inferior retinal detachment (RD). After conventional pars plana vitrectomy and posterior vitreous detachment induction, fluid-gas exchange using 14% C3F8was done. This was followed by silicone oil injection using automated infusion pump to 50% fill of the vitreous cavity under direct visualization to achieve formation of two bubbles – gas bubble superiorly and silicone oil inferiorly. The patient was subsequently asked to maintain upright position. The two immiscible bubbles of C3F8and silicone oil provide tamponade to superior and inferior retina, respectively. With time, gas bubble reduces in size with a gradual superior shift of silicone oil. This novel sandwich technique achieves complete attachment of retina and reduces the risk of retinal redetachment in inferior RDs by adequately tamponading the inferior retina.

Introduction:  Incidental dural tears (IDTs) are sometimes observed as an intraoperative complication associated with lumbar spine surgery. Commonly, this complication is recognized and repaired during surgery, but if it is undiagnosed or inadequately treated, a variety of consequences may occur. Many techniques have been developed to treat cerebrospinal fluid (CSF) leakage, and each has its limitations.  Objectives: To assess the prevalence of incidental dural tears in lumbar spine surgeries and evaluate the outcomes of the sandwich technique in the management of this complication., Methods: A total of 92 patients who underwent lumbar spine surgery at the Royal Rehabilitation Center in Amman from January 2018 to December 2021 were retrospectively reviewed. Patients were divided into two groups: group A (patients without IDT) and group B (patients with IDT), where group B was repaired using the sandwich technique. The follow-up period was six months. Further, the sandwich technique involves repairing the dural defect with interlocking sutures, painting medical glue around the dural incision, covering this with gelatin sponge, and finally covering the gelatin sponge with medical glue again., Results: The overall prevalence of IDT in the study group was 14.1%. IDT was more common among elderly patients above the age of 60 (17.2%), females (16.7%), patients with multiple lumbar levels treated (66.7%), open approaches (21%), and those who had previous spinal surgery (72.7%). Most IDTs were diagnosed and managed intraoperatively (84.6%). Among those patients, only one complained of a surgical site infection. Patients in group B had a significantly higher postoperative length of hospital stay, amount of drainage, and operative time compared to group A (P<0.001). Regarding postoperative pain, patients in group B had significantly higher pain on the Numerical Pain Scale at day three post-operation compared to patients in group A (P<0.001)., Conclusion: Based on our results, the sandwich technique was effective in the management and prevention of CSF leakage. Further prospective studies with long-term follow-up are needed to confirm our findings., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Alessa et al.)

Objective: This study investigated the shear bond strength (SBS) and interface between a resin composite and a new high-viscous glass ionomer cement (HV-GIC), a HV-GIC, a resin-modified glass ionomer cement (RM-GIC), a bulk-fill flowable composite, and a regular flowable composite bonded with various adhesive systems. Methods and materials: A resin composite (Filtek Z350) was bonded to a new HV-GIC (EQUIA Forte Fil) using various adhesive systems, including a universal adhesive in self-etch and etch-and-rinse mode (Scotchbond Universal), a two-step etch-and-rinse adhesive (Scotchbond 1-XT), a one-step self-etch adhesive (Optibond All-in-one) tested also after silane application (Monobond Plus), and a coating material (EQUIA Forte Coat). The resin composite was also bonded to a HV-GIC (Fuji IX GP), a RM-GIC (Fuji II LC), a bulk-fill flowable composite (SDR), and a regular flowable composite (Tetric Evo Flow) with the universal adhesive in self-etch mode (Scotchbond Universal). Two-way ANOVA followed by Dunnett's post hoc test was used to investigate the difference in SBS. Failures were analyzed by chi-square test. Bonding interfaces were examined by environmental scanning electron microscopy (E-SEM). Results: SBS to EQUIA Forte Fil was significantly lower with Scotchbond 1-XT than with all other adhesive systems. By using Scotchbond Universal with the self-etch technique, the SBS to EQUIA Forte Fil was significantly higher than the SBS to Fuji IX GP and significantly lower than the SBS to Fuji II LC, SDR, and Tetric Evo Flow. E-SEM images showed an intimate contact at all interfaces examined. Conclusion: EQUIA Forte Fil showed satisfactory SBS and interfaces with all adhesives tested. Clinical relevance: Bonding between the resin composite and HV-GIC can be achieved using a universal adhesive in self-etch mode, an easy-to-use adhesive system. [ABSTRACT FROM AUTHOR]

Hypogastric artery aneurysms (HAA) necessitate repair due to significant morbidity and potential mortality associated with rupture. Coverage or coiling of HAA are not always possible, as the risk of pelvic and spinal cord ischemia become especially significant in bilateral hypogastric disease as well as with prior extensive aortic coverage. We report 2 cases of endovascular HAA exclusion using parallel stent grafts for preservation of flow through the distal hypogastric artery branches and external iliac artery in patients with prior thoracic and abdominal aortic repairs, contralateral hypogastric disease, and significant anatomic constraints. [ABSTRACT FROM AUTHOR]

The adhesion of resin-modified glass-ionomer (RMGI) to composite resin plays a very important role in the durability of sandwich restorations. Aim - to explore that co-curing RMGIC and composite resin to GIC using self-etch adhesives and bulk-fill materials may create a chemical bond and improve the bond strengths between these two materials. Materials and methods. Twenty specimens were prepared on gypsum blocks, with wells prepared in them by drilling holes, to retain the RMGIC. The specimens were randomly divided into two groups of 10 specimens each. In group I, after etching and rinsing the surface of cement, a thin layer of an adhesive, which was a Total-Etch type, was applied between RMGIC and the composite resin. In group II, the stage of etching was missed, a Self-Etch adhesive and a thin layer of bulk fill material were applied on the cement surface. Then after curing all the specimens, the shear bond strength was measured using a Bisco Shear bond testing machine. Failure mode was assessed under a stereomicroscope. Results. There were statistically significant differences in bond strengths between the groups (P< 0.05). Failures were predominantly of the cohesive type in all the groups. Conclusion. Based on the results of this study, the use of self-etch adhesive resin on the unset glass-ionomer and using bulk-fill material yielded the highest bond strength in the combined use of glass-ionomer cement and composite material.

A simple sandwich technique using buttons to compress grafted tissue combined with a tie-over technique for intraoral split-thickness skin grafts (STSGs) is introduced. This technique yielded an excellent engraftment rate (90.5%) and no instances of total graft failure were recorded. This simple sandwich technique for STSGs is readily applicable and inexpensive, and the present results show that it would be potentially useful for repair of defects in the oral cavity. [ABSTRACT FROM AUTHOR]

Pancreatic pseudoaneurysm is a rare but life-threatening clinical entity. In this paper, we present a case of a 74-year-old man, who was admitted to our clinic with a diagnosis of an acute on chronic pancreatitis complicated by walled-off-pancreatic-necrosis, with subsequent development of peripancreatic pseudoaneurysm. After initial conservative management, the patient recovered and was discharged from the hospital. However, he soon returned feeling anxious due to a pulsatile abdominal mass. Abdominal Color–Doppler examination, CT scan, and angiography revealed large pancreatic necrotic collection in the total size of 9 cm, with centrally enhancing area of 3.5 cm that corresponded to pseudoaneurysm originating from the posterior pancreaticoduodenal vascular arcade. Considering the size, location of the pseudoaneurysm, feeding vessel, and poor general patients condition, we opted for minimally invasive treatment. Pseudoaneurysm was successfully managed by endovascular coil embolization, i.e., “sandwich technique”.

IntroductionIn a systematic review of the surgical treatment of large incisional hernia sublay repair, the sandwich technique and aponeuroplasty with intraperitoneal mesh displayed the best results. In this systematic review only the sandwich technique, which used the hernia sac as an extension of the posterior and anterior rectus sheath and placement of a non-absorbable mesh in the sublay position, was included. Other modifications of the sandwich technique are published in the literature and were also analyzed in this literature review.MethodsA systematic search of the available literature was performed in November 2017 using Medline, PubMed, and the Cochrane Library using the terms “sandwich technique”, “double prosthetic repair”, “double mesh intraperitoneal repair”, and “component separation technique with double mesh”. This review is based on 24 relevant publications. Unfortunately, the evidence of the available studies is not very high since only prospective and retrospective case series have been published. There are no comparative studies at all. Therefore, the findings of the published case series must be viewed in a critical light.ResultsThe published studies report a remarkably low recurrence rate of 0-13% with a follow-up of 1–7 years. One limitation that must be mentioned here is that in around half of the studies the method of follow-up was not specified and in the remaining cases this was based on clinical examination by the surgical team. This puts into perspective the reported results, which appear to be too favorable given the complex nature of the hernias involved.The major disadvantage of the sandwich technique is a very high rate of wound complications of up to 68%, mainly induced by creation of large skin and subcutaneous cellular tissue flaps.ConclusionIt is difficult to evaluate the significance of the various modifications of the “sandwich technique” based on the available literature since it includes only case series and no comparative studies. The techniques used are associated with very high wound complication rates but with only relatively low recurrence rates despite the complexity of the cases involved. This must be verified in studies with a well-designed methodology.