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Kajian Struktur Rangka Batang Jembatan Wailola Besar Kabupaten Seram Bagian Timur

The Wailola Besar Bridge, which is located in Bula District, East Seram Regency, has a Warren truss type frame structure. However, unlike the truss used on other bridges, the truss on the Wailola Besar bridge has a larger size than the others. Because the span of the Wailola Besar bridge is 80 m, while the span of other bridges using the Warren truss type is a maximum of 60 m. The larger size than the other trusses makes the Wailola Besar bridge have a different truss from other trusses. The length of each horizontal bar is 6.65 m, while the maximum length for other bridges is 5 m. Then the purpose of this study is to determine whether the truss structure of the Wailola Besar bridge is capable of carrying the loads acting on the bridge, the method used is with the help of the SAP-2000 program to determine the truss forces then controlled with allowable voltage. In order to know whether the structure is able to withstand the forces acting. From the results of calculations with the help of SAP-2000 the rod forces acting on the largest truss structure are 11066.881 KN at constant loading and 12222.547 KN at temporary loading and the stress that occurs is 1742.82 Kg/〖cm〗^2. at constant loading and 1924.81 Kg/〖cm〗^2. The stress that occurs in the truss does not exceed the allowable stress.

Changes in microbial communities during high-rate microbial selenate reduction in an up-flow anaerobic fluidized bed reactor

Biological fluidized bed reactor (FBR) is a promising treatment option for removing selenium oxyanions from wastewater by converting them into elemental selenium. The process can achieve high rates and be efficiently operated at low hydraulic retention times (HRT). However, the effects of HRT on the changes in microbial community in the FBR process have not been previously explored. In this study, dynamic changes of microbial communities both on biofilm carrier and in suspension of a selenate-reducing FBR were explored at various HRTs (0.3–120 h). Based on partial 16S rRNA gene sequencing of the microbial communities, alpha diversity of microbial communities in suspension rather than in the biofilm were impacted by low HRTs (0.3 h–3 h). Members from genera Geobacter, Geoalkalibacter, and Geovibrio were the main selenate-reducing bacteria on carrier throughout the FBR process. Genus Geobacter was dominant in FBR carrier at HRT of 24 h–120 h, whereas Geoalkalibacter and Geovibrio dominated at low HRT of 0.3 h–6 h. Suspended microbial communities detected in the FBR effluent were more sensitive to HRT changes than that in biofilm. “Shock loading” at HRT of 0.3 h had a great impact on microbial community compositions both in the biofilm and effluent. Reactor operation in batch mode and long HRT of 24 h helped recover the community from “shock loading” and improved selenite reduction and ethanol oxidation. Redundancy analysis revealed that HRT, influent pH and selenate loading were key operational parameters impacting both the FBR performance and the composition of microbial communities associated with both the FBR carrier and effluent. Overall, the microbial communities in FBR biofilm flexibly responded to the changes of HRT and showed resilience to the temporary shock loading, enabling efficient selenate removal.

Parametric optimization and case study of nanofluid flow between two parallel plates in the presence of Darcy Brinkman Forchheimer: Sensitivity analysis

Due to its vast industrial applications and thermal engineering, the investigation of the inconsistent heat and mass transfer that drives the flow of squeezing viscous nanofluids between two plates is an interesting topic. In this case study, we have investigated the heat transfer analysis of unsteady viscous nanofluid between two parallel plates by using Response Surface Methodology (RSM). The partial differential equations illustrating the flow model are converted to nonlinear ordinary differential equations by suggesting similarity transformations. The resulting dimensionless and nonlinear ODEs of temperature functions and velocity are solved using the well-known numerical technique bvp4c by transforming the problem into initial value problem from boundary value problem. The results found are consistent with this numerical solution. These numerical values are then used to optimize the different input parameters and to design an experimental model. RSM is used to develop an experimental model for skin friction coefficient. ANOVA tables are generated for input parameters and then sensitivity analysis is performed for output response. Further, the impacts of different parameters on temperature profiles and velocity are graphically explored. The results are compared with the results solved by HPM. The results concurred with this numerical solution. These findings considered much be useful in the application of polymer processing, power transmission, compression, temporary loading of mechanical parts, food processing, cooling water, gravity machinery, modeling of plastic transport in vivo, chemical processing instruments, and demolition due to freezing.

Constructing an Osseointegrated Prosthetic Leg.

Constructing an osseointegrated prosthetic leg is the necessary subsequent phase of care for patients following the surgical implantation of an osseointegrated prosthetic limb anchor. The surgeon implants the bone-anchored transcutaneous implant1,2 and the prosthetist constructs the prosthetic leg, which then attaches to the surgically implanted anchor. An osseointegration surgical procedure is usually considered in patients who are unable to use or are dissatisfied with the use of a socket prosthesis. This present video article describes the techniques and principles involved in constructing a prosthetic leg for transfemoral and transtibial amputees, as well as postoperative patient care. Preoperatively, as part of a multidisciplinary team approach, the prosthetist should assist in patient evaluation to determine suitability for osseointegration surgery. Postoperatively, when approved by the surgeon, the first step is to perform an implant inspection and to take patient measurements. A temporary loading implant is provided to allow the patient to start loading the limb. When the patient is approved for full-length leg to begin full weight-bearing, the implant and prosthetic quality are evaluated, including torque, implant position, bench alignment, static alignment in the standing position, and initial dynamic alignment. This surgical procedure also requires long-term, continued patient care and prosthetic maintenance. For patients who are dissatisfied with the use of a socket prosthesis, adjustments can often be made to improve the comfort, fit, and performance of the prosthesis. Non-osseointegration surgical options include bone lengthening and/or soft-tissue contouring. Osseointegration can be provided for amputees who are expressing dissatisfaction with their socket prosthesis, and typically provides superior mobility and quality of life compared with nonoperative and other operative options3,4. Specific differences between the appropriate design and construction of osseointegrated prostheses versus socket prostheses include component selection, component fit, patient-prosthesis static and dynamic alignment, tolerances and accommodations, and also the expected long-term changes in patient joint mobility and behavior. Providing an osseointegrated prosthesis according to the principles appropriate for socket prostheses may often leave an osseointegrated patient improperly aligned and provoke maladaptive accommodations, hindering performance and potentially putting patients at unnecessary risk for injury. Review articles describing the clinical outcomes of osseointegration consistently suggest that patients with osseointegrated prostheses have improved prosthesis wear time, mobility, and quality of life compared with patients with socket prostheses. Importantly, studies have shown that osseointegrated prostheses can be utilized in patients with short residual limbs that preclude the use of a socket prosthesis, allowing them to regain or retain function of the joint proximal to the short residuum5,6. Osseoperception improves patient confidence during mobility7. Because there is an open skin portal, low-grade soft-tissue infection can occur, which is usually treated with a short course of oral antibiotics. Much less often, soft-tissue debridement or implant removal may be needed to treat infection8. Periprosthetic fractures can nearly always be treated with familiar fracture fixation techniques and implant retention9,10. Falls can lead to periprosthetic fractures.Malalignment can lead to unnecessary pathologic joint forces, soft-tissue contractures, and an accommodative gait.Inadequately sophisticated components can leave patients at a performance deficit.Wearing the prosthetic leg while sleeping may lead to rotational forces exerted on the limb, which may cause prolonged tension on the soft tissue. QTFA = Questionnaire for Persons with a Transfemoral AmputationLD-SRS = Limb Deformity Modified Scoliosis Research SocietyPROMIS = Patient-Reported Outcomes Measurement Information SystemEQ-5D = EuroQol 5 Dimensions.

Curative measures identification in congestion management exploiting temporary admissible thermal loading of overhead lines

This paper demonstrates how to consider thermal reserves of overhead lines in optimization problems for congestion management with preventive (pre-fault) and curative (post-fault) actions effectively to ensure N-1 security. Solving congestions curatively allows for higher base loadings and reduced congestion management volumes. At the same time, assets are exposed to higher risks of damage. The two proposed methods incorporate precise permanent and temporary admissible loading constraints for base and contingency situations already at the operational planning stage. The methods ensure that conductor temperatures stay below the assets’ thermal limits at all times. The benefits of exploiting thermal reserves are analyzed in a case study to the future German transmission grid of 2030.

Vibration performance assessment of deteriorating footbridges: A study of Tunja’s public footbridges

This paper presents the results of the assessment of the dynamic characteristics and vibration performance of eight deteriorating footbridges. The bridges examined, part of the public infrastructure of the city of Tunja (Colombia), present an evident state of deterioration, showing excessive vibration under service loadings. A consistent evaluation methodology based on vibration tests and numerical analyses was implemented. After completing a deterioration assessment, an experimental modal characterization was carried out, the results of which were used to update numerical structural models. Uniform vibration tests for different pedestrian loading scenarios were conducted. Then, pedestrian crossing simulations for a typical range of walking and running frequencies were performed using a step-by-step load model with a new proposal of normalised single-footstep force functions. Results showed elevated vibrations in most of the footbridges for temporary and exceptional loading conditions, which are unsafe for some of the structures. Discomfort and deterioration were compared using a vibration discomfort index (VDI) and a deterioration index (DI). High vibration discomfort levels were found to be consistent with the degree of deterioration of the structures evaluated.

An experimental pig model with outer retinal degeneration induced by temporary intravitreal loading of N-methyl-N-nitrosourea during vitrectomy

We aimed to develop an outer retinal degeneration pig model induced by temporary intravitreal loading of N-methyl-N-nitrosourea (MNU) during vitrectomy. In a preliminary experiment involving 5 mini-pig cases to determine the appropriate concentration of MNU, the vitreous cavity of each eye was filled with 4, 8, 10, 12, or 16 mg/mL MNU for 10 min, which was then replaced with a balanced salt solution. Multimodal examinations including spectral-domain optical coherence tomography (OCT) images and full-field electroretinography (ffERG) were obtained at baseline and week 2, week 6, and week 12. The retinal degeneration was classified according to the amplitudes of a dark adaptive (DA) 10.0 a-wave amplitude. The degree of moderate retinal degeneration was defined as DA 10.0 a-wave amplitude ≥ 10% and < 60% of baseline amplitude. The degree of severe degeneration was defined as DA 10.0 a-wave amplitude < 10% of baseline amplitude, noise, or flat signal. Hematoxylin and eosin staining and immunohistochemistry were performed at week 12. The main experiments were conducted first with 10 cases of 5 mg/mL and later with 13 cases of 10 mg/mL. In the preliminary experiment, degree of outer retinal degeneration increased with MNU concentration. Use of 4, 8, 10, 12, and 16 mg/mL MNU showed no, moderate, severe, severe, and atrophic changes, respectively. In the main experiments, there were 9 cases of moderate retinal degeneration and 1 case of severe degeneration in 5 mg/mL MNU group. Two cases of moderate degeneration and 11 of severe degeneration were recorded in 10 mg/mL group. Mean thickness of total retina, inner nuclear layer, and outer nuclear layer decreased at week 2 in both groups. The mean amplitudes on ffERG decreased at week 2. The ffERG and OCT findings did not change from week 2 to week 6 or week 12. The results of staining supported those of ffERG and OCT. Temporal MNU loading in a vitrectomized pig-eye model induced customized outer retinal degeneration with changing the concentration of MNU.

Fast computation method of static voltage stability using geometric parameter adjustment for the continuation power flow

AbstractThis paper presents a fast computation method of static voltage stability using geometric parameter adjustment for the continuation power flow. The conventional method has the following problems: voltage stability assessment (VSA) is high accuracy but there is much total convergence calculation number of times. The features of the proposed method are following: (1) to change the step size of a geometric parameter in prediction part, (2) to adjust a geometric parameter using temporary maximum loading point (MLP) by Look‐Ahead method. The proposed method has an advantage of being able to maintain high accuracy for VSA and to calculate less total convergence calculation number of times than conventional methods in IEEE test case of 118 and 300 bus systems.

Stress-free-state based structural analysis and construction control theory for staged construction bridges

Structural analysis and construction control of staged construction process is a major subject for modern long-span bridges. This paper introduces the concept of stress-free-state variable of structural elements and deduces the mechanical equilibrium equations and geometric shape governing equations for staged construction structures utilizing the minimum potential energy theorem. As the core of stress-free-state theory, the two aforementioned equations demonstrate following principles, 1) when the stress-free-state variable of a structural element is set, the internal force and deformation of the element are unique at the completion state of the structure regardless of its construction process; 2) the stress-free length of a cable is independent of its external loads, change in stress-free length of the cable corresponds to a unique variation of the cable force when load is constant; and 3) the internal force of a structural element can be independent from its geometric shape within the completion state of a staged construction structure through an active manipulation of stress-free-state variables of the element. Stress-free-state theory establishes the stage-to-stage and stage-to-completion relationships for staged construction bridges, provides a direct and efficient method for theoretical calculations and a flexible and convenient approach for the control of staged construction, and makes parallel construction and auto-filtering of thermal and temporary loading effect possible.

Temporary Loading Prevents Cancer Progression and Immune Organ Atrophy Induced by Hind-Limb Unloading in Mice.

Although the body’s immune system is altered during spaceflight, the effects of microgravity (μG) on tumor growth and carcinogenesis are, as yet, unknown. To assess tumor proliferation and its effects on the immune system, we used a hind-limb unloading (HU) murine model to simulate μG during spaceflight. HU mice demonstrated significantly increased tumor growth, metastasis to the lung, and greater splenic and thymic atrophy compared with mice in constant orthostatic suspension and standard housing controls. In addition, mice undergoing temporary loading during HU (2 h per day) demonstrated no difference in cancer progression and immune organ atrophy compared with controls. Our findings suggest that temporary loading can prevent cancer progression and immune organ atrophy induced by HU. Further space experiment studies are warranted to elucidate the precise effects of μG on systemic immunity and cancer progression.

"Track-Bridge" Interaction Problems in High Speed Bridge Design

Track-bridge interaction problems have a main role in the design of bridges on high speed railways (HSR). In this paper, a technique is described for performing calculations of the interaction of the elements of the "bridge-jointless track" system. The complexity of these calculations lies in the nonlinear relationship between the bridge spans and the railway track. The characteristics of these relationships are largely determined by climatic factors (summer and winter conditions), as well as the presence of temporary loading on the bridge. The results of the interaction "bridge-jointless track" system are presented at temperature and train impacts for the characteristic types of bridge structures in the form of multi-span beams and continuous beams. The influence of the length, the construction scheme, the longitudinal stiffness of the intermediate supports on the magnitude of the forces arising in the rails of the continuous path is shown. Based on the performed calculations, conclusions were drawn about the characteristic modes of operation of the "bridge-jointless track" system and recommendations were made on constructive measures reducing efforts in rails.

Evaluation of liner responses due to non-uniform tail void grouting pressure

ABSTRACTTail void grouting initially does facilitate the action of ground loads around the lower half of the liner and no excess pressure being accumulated. However, at a later stage (almost at the completion of grouting), grout pressure becomes non-uniformly distributed around grout injection holes especially on the upper half of the liner. In the present study, the boundary and loading conditions were simulated by using a series of finite element analyses. It aimed to explore the effects of such temporary non-uniform loading conditions on development of the liner internal forces. The results obtained for tunnel with diameter of 6.0 m were presented. It was found that there were critical locations where application of non-uniform grouting pressure could result in large amounts of bending moment and deformation. Those critical locations; about ±30° to ±50° from crown of the tunnel, were about the locations where actual grouting was injected in the field. The stiffness of sub-soil beneath the tunnel invert had minor effect on the amount of induced structural forces. However, ground coverage was more important. The results, though cannot fully represent complicated tail grouting behaviours, provided a simple analytical procedure for exploring the effects of tail void grouting on the segmental liner.

Magnetic Resonance Imaging-Guided High–Dose Rate Brachytherapy for Cervical Cancer

Introduction Cervical cancer represents 0.8% of all new cancer cases and in 2012 there was an estimated 249,512 women living with cervical cancer in the United States. Concurrent chemoradiation followed by brachytherapy represents the standard of care in patients with International Federation of Gynecology and Obstetrics stage IB2 to IVA tumors (tumors larger than 4 cm or with parametrial involvement). During the first phase of treatment, patients receive external beam radiotherapy (EBRT) to the pelvis specifically targeting the cervix, uterus, and regional lymphatics. Patients typically receive 45-50.4 Gy with concurrentweekly cisplatin over 5weeks. This is followed by brachytherapy where applicators are placed in close proximity to the tumor typically via an intracavitary approach for temporary loading of a radioactive source. Brachytherapy plays a crucial role in the management of invasive cervical cancer. It has a rapid dose fall off allowing the tumor to receive a high dose while relatively sparing nearby structures such as the bladder, sigmoid, and rectum. Brachytherapy delivery options have evolved over time and can be delivered through multiple (typically 5) outpatient procedures using a high–dose rate source or during 2 inpatient stays using a low–dose rate source. By taking advantage of the geometric andphysical properties of brachytherapy, the central principle is to escalate the tumor dose to a curative rangewhileminimizing the dose and toxicity to the surrounding organs at risk (rectum, bladder, and sigmoid). Over time with advances in imaging, brachytherapy treatment planning has evolved tomeet these goals. In the early era, brachytherapy was planned using 2-dimensional images (Fig. 1). Defined points in space were used to evaluate the quality of brachytherapy implants and to estimate the tumor dose and dose to organs at risk. With the widespread use of computed tomography (CT) within radiation oncology departments, CT-based planning (Fig. 2) is now feasible. The

Precast segments under TBM hydraulic jacks: Experimental investigation on the local splitting behavior

The design process of segmental concrete linings in ground conditions generally refers to standard load cases of de-molding, storage, embedded ground condition and grouting process. Nevertheless, the application of the Tunnel Boring Machine (TBM) thrust jack forces is a crucial temporary loading condition during construction, which may govern the design procedure as well as the other stages.Tunnel segments were traditionally reinforced with conventional rebars in order to resist the tensile stresses at both Serviceability (SLS) and Ultimate Limit States (ULS). In the two last decades, Fiber Reinforced Concrete (FRC) has been also used in several precast tunnel segments with or without conventional rebars. For structural purposes, steel fibers are generally used, even though some types of structural macro-synthetic fibers, which are able to impart significant toughness and ductility to concrete, have been recently introduced in the market. For these reasons, an experimental program aimed to investigate the local splitting behavior in the segment regions under the TBM hydraulic jacks was carried out at the University of Brescia. Tests on concrete prisms (with or without fibrous reinforcement) under Line Load (LL) or Point Load (PL) configurations were carried out in order to evaluate the beneficial effects of polypropylene (PP) fibers in controlling typical splitting cracks occurring under the jack loads, which represent one of the most severe loading conditions for tunnel segments. Experimental results show the feasibility of using polypropylene fibers in tunnel segments, since they significantly enhance both the splitting bearing capacity and the ductility. Fibers lead to a stable development of the splitting crack, which allows a redistribution of stresses after cracking. However, the effectiveness of fibers is influenced by the casting direction, which leads to a different fiber orientation. When the latter is favorable (fibers expected to be mainly transversal to the splitting crack) the bearing capacity is higher than in case of an unfavorable casting direction (fibers expected to be mainly parallel to the splitting crack).

Effect of preloading on the amplification characteristics of soil profiles

Preloading is a temporary loading, usually an embankment, applied to improve subsurface soils by densification. This paper studies the effect of preloading on the amplification characteristics of soft sites with an elaborate parametric analysis. The soil type, the depth of the bedrock, the water table depth, the level of preloading, the applied earthquake, the shear wave velocity of the bedrock and the shear modulus and damping versus shear strain relations were varied in a systematic manner. The analysis was performed by the commonly used one-dimensional equivalent-linear dynamic method. The shear wave velocity versus depth and the effect of preloading on shear velocity are computed with well-established soil mechanics equations. The results illustrated that the seismic response at the top of the profile generally decreases as a result of preloading. A more detailed analysis of results shows that the effect of preloading on the seismic response depends on the soil type and the depth of the bedrock. Based on these results, a method is proposed by which a practicing engineer involved with improvement of soft ground can simulate the effect of preloading on the seismic motion.

Temporary Adjunctive Cilostazol vs Clopidogrel Loading for ST-segment Elevation Acute Myocardial Infarction

Clopidogrel loading is a standard method to achieve rapid platelet inhibition and prevent thrombotic events. At the current time, little information is available to determine the effect of adjunctive cilostazol compared with clopidogrel loading. We retrospectively analyzed 212 patients undergoing primary percutaneous coronary intervention with drug-eluting stents for ST-segment elevation acute myocardial infarction. All patients were administered aspirin (100 mg once a day) and clopidogrel (75 mg once a day). The patients were divided into two groups according to the presence (loading group, n = 100) or absence (cilostazol group, n = 112) of clopidogrel loading (300 mg). Patients in the cilostazol group were administered adjunctive cilostazol (100 mg twice a day) in place of clopidogrel loading. Patient characteristics, medications, and 30-day clinical outcomes were examined. The mean duration of cilostazol administration in the cilostazol group was 6.2 ± 4.9 days from the time of primary coronary intervention. No significant difference was observed in major adverse cardiac events (cardiac death, definite stent thrombosis, and non-fatal myocardial infarction) between the loading group and the cilostazol group (9/100; 9.0 vs. 8/112; 7.1%, p = 0.62). Definite stent thrombosis was observed for two patients in the loading group and one patient in the cilostazol group. The occurrence ratio of bleeding events did not differ significantly between the two groups (9.0 vs. 5.4%, p = 0.30). There was no significant difference in the incidence of major adverse cardiac events between temporary adjunctive cilostazol treatment and clopidogrel loading in ST-segment elevation acute myocardial infarction patients. Our findings suggest one potential of cilostazol.

Numerical investigation of the failure of a building in Shanghai, China

The overturning failure of a 13 storey residential building in Shanghai, China, has been investigated by plane strain finite element analysis (FEA). The results of the FEA indicate that ultimate failure of the building was probably initiated by the formation of tensile cracking in the reinforced concrete piles located under the side of the building adjacent to an excavation. This eventually led to complete structural failure of the piles located along the excavation side, which probably caused further settlement of the building, leading eventually to a toppling failure resulting in overturning of the entire building. Excessive tensile stress in the piles was probably caused by the combination of excavation of soil at one side of the building and the temporary dumping of the excavated soil on the opposite side of the building. It is likely that the effect of temporary dumping of the excavated soil adjacent to the building was either not considered or not properly taken into account in the foundation design nor the construction operations. A simple but important lesson to be draw from this failure is the need for engineers who design foundations in soft soil regions to consider not only the final loading conditions, but also any temporary and transient loading conditions during the construction process.

Pre-loading effect on site response: Site amplification and soil properties mismatch

A field experiment with a temporary embankment loading gave the opportunity to evaluate changes of both soil properties and site response, due to a low stiffness shallow soil model. The Quarter Wave-Length approximation is mainly used to quantitatively indicate the expected changes. The original Vs models derived by seismic prospecting methods (Raptakis. Soil Dynamics and Earthquake Engineering 2012;34: 69–77), similarly performed prior to and after preloading, were used for site amplification estimates as a function of frequency. The quantitative comparisons of either results derived by field techniques combined to each other or those of each technique separately before and after preloading, reveal changes in site response showing a clear de-amplification after preloading but of lower order than stiffness increase. This fact may have beneficial manpower and cost consequences on the acquisition of the most “detailed” and “reliable” Vs input model for site response studies. Among others, the fact that a significant disparity between amplifications is observed only after preloading indicates that changes in the soil properties refer to the ground hypotheses for which the exploration tools present by principle limitations and drawbacks.

Design, modeling, and analysis of a feedstock logistics system

Given the location of a bio-energy plant for the conversion of biomass to bio-energy, a feedstock logistics system that relies on the use of satellite storage locations (SSLs) for temporary storage and loading of round bales is proposed. Three equipment systems are considered for handling biomass at the SSLs, and they are either placed permanently or are mobile and thereby travel from one SSL to another. A mathematical programming-based approach is utilized to determine SSLs and equipment routes in order to minimize the total cost. The use of a Side-loading Rack System results in average savings of 21.3% over a Densification System while a Rear-loading Rack System is more expensive to operate than either of the other equipment systems. The utilization of mobile equipment results in average savings of 14.8% over the equipment placed permanently. Furthermore, the Densification System is not justifiable for transportation distances less than 81km.

Zygomatic Implant Placement With Flapless Computer-Guided Surgery: A Proposed Clinical Protocol

The aim of the present report is to describe a procedure for zygomatic implant placement using image-guided implant surgery. This is an innovative technique and includes a new clinical approach to provide the direction to guide drilling. The ethical committee of the University of Genoa approved the study. All patients had clinical indications of severe maxillary atrophy (Class 4 Cadwood-Howell). A total of 25 implants were placed, of which 17 were in the premaxilla, 7 in the zygomatic area, and 1 in the pterygoid bone. The treatment was performed in 2 phases. The first phase included cone-beam acquisition to exclude sinus disease and evaluate the anatomy of the residual premaxillary bone in 3 dimensions. The success of osseointegration achieved by the primary implants (PIs) was confirmed after temporary loading and before proceeding with the second phase, in which all patients were scheduled for zygomatic implants. A total of 3 or 4 regular platform MK III implants (17 in all) were placed in the premaxilla using conventional implant surgery. A model within the analogs of the PIs was prepared (master model), taking a conventional impression. Next, a radiologic template was prepared on the same master model and stabilized on the PIs, using dedicated prosthetic components. The guide was screwed onto the PIs during computed tomography acquisition to determine a fixed and repeatable position of the guide. In the second phase, after routine planning, a mucosa-supported stereolithographic SurgiGuide with sleeves for the zygomatic implants and the corresponding stereolithographic model, including the mucosa, were received from the manufacturers. The guide was repositioned on the master model to replace the sleeves for the PIs in the same position. With an original customized surgical kit, including an innovative intrasinus device, we next simulated surgery on the stereolithographic model to determine and control the direction of the osteotomies and the final depth of drilling. The SurgiGuide was anchored onto the PIs before the zygomatic osteotomy, after which flapless surgery was performed to place the zygomatic implants according to the plan. Two PIs in the premaxillary area failed (and were replaced before the zygomatic step). No zygomatic implants failed. The follow-up examinations at 4 to 39 months showed good esthetic, phonetic, and functional results. The results of the proposed surgical procedure appear to be encouraging. Although it is difficult to achieve the correct driven angle of osteotomies for zygomatic implants, in all patients we achieved correct zygomatic positioning, in agreement with previous planning. Additional research and randomized clinical trials are needed to assess the predictability of the procedure.