Compact and modular system architecture for a nano-resonator-mass spectrometer.

Mass measurements in the mega-to giga-Dalton range are essential for the characterization of natural and synthetic nanoparticles, but very challenging to perform using conventional mass spectrometers. Nano-electro-mechanical system (NEMS) based MS has demonstrated unique capabilities for the analysis of ultra-high mass analytes. Yet, system designs to date included constraints transferred from conventional MS instruments, such as ion guides and high vacuum requirements. Encouraged by other reports, we investigated the influence of pressure on the performances of the NEMS sensor and the aerodynamic focusing lens that equipped our first-generation instrument. We thus realized that the NEMS spectrometer could operate at significantly higher pressures than anticipated without compromising particle focusing nor mass measurement quality. Based on these observations, we designed and constructed a new NEMS-MS prototype considerably more compact than our original system, and which features an improved aerodynamic lens alignment concept, yielding superior particle focusing. We evaluated this new prototype by performing nanoparticle deposition to characterize aerodynamic focusing, and mass measurements of calibrated gold nanoparticles samples. The particle capture efficiency showed nearly two orders of magnitude improvement compared to our previous prototype, while operating at two orders of magnitude greater pressure, and without compromising mass resolution.

Requirements and attributes of nano-resonator mass spectrometry for the analysis of intact viral particles.

When studying viruses, the most prevalent aspects that come to mind are their structural and functional features, but this leaves in the shadows a quite universal characteristic: their mass. Even if approximations can be derived from size and density measurements, the multi MDa to GDa mass range, featuring a majority of viruses, has so far remained largely unexplored. Recently, nano-electromechanical resonator-based mass spectrometry (NEMS-MS) has demonstrated the ability to measure the mass of intact DNA filled viral capsids in excess of 100 MDa. However, multiple factors have to be taken in consideration when performing NEMS-MS measurements. In this article, phenomena influencing NEMS-MS mass estimates are listed and discussed, including some particle's extraneous physical properties (size, aspect ratio, stiffness), and the influence of frequency noise and device fabrication defects. These factors being accounted for, we could begin to notice subtler effects linked with (e.g.) particle desolvation as a function of operating parameters. Graphical abstract.

CHICKN: extraction of peptide chromatographic elution profiles from large scale mass spectrometry data by means of Wasserstein compressive hierarchical cluster analysis.

BACKGROUND: The clustering of data produced by liquid chromatography coupled to mass spectrometry analyses (LC-MS data) has recently gained interest to extract meaningful chemical or biological patterns. However, recent instrumental pipelines deliver data which size, dimensionality and expected number of clusters are too large to be processed by classical machine learning algorithms, so that most of the state-of-the-art relies on single pass linkage-based algorithms. RESULTS: We propose a clustering algorithm that solves the powerful but computationally demanding kernel k-means objective function in a scalable way. As a result, it can process LC-MS data in an acceptable time on a multicore machine. To do so, we combine three essential features: a compressive data representation, Nyström approximation and a hierarchical strategy. In addition, we propose new kernels based on optimal transport, which interprets as intuitive similarity measures between chromatographic elution profiles. CONCLUSIONS: Our method, referred to as CHICKN, is evaluated on proteomics data produced in our lab, as well as on benchmark data coming from the literature. From a computational viewpoint, it is particularly efficient on raw LC-MS data. From a data analysis viewpoint, it provides clusters which differ from those resulting from state-of-the-art methods, while achieving similar performances. This highlights the complementarity of differently principle algorithms to extract the best from complex LC-MS data.

Patient-Reported Outcome Measures (PROMs) for Two Implant Placement Techniques in Sinus Region (Bone Graft versus Computer-Aided Implant Surgery): A Randomized Prospective Trial.

PURPOSE: To assess patient-reported outcomes measures (PROMs) for two implant placement techniques in cases of sinus bone atrophy (bone graft surgery (BGS) versus computer-aided implant surgery (CAIS)), after surgery and one year later, and to evaluate the clinical success of both treatments. METHODS: Sixty patients with bone atrophy in the posterior maxilla and in need of implant placement were randomly assigned to two groups, and in accordance with the case report form (CRF), 30 were treated with BGS and 30 with CAIS. Immediately after treatment and one year later, PROMs were assessed, and the clinical success of both treatments was evaluated. RESULTS: No significant differences were found between BGS and CAIS with regard to the following: loss of implants (p = 492); patient recommendation (p = 210); duration of surgery (p = 987); pain on the intervention day (p = 512); pain in the week after intervention (p = 299); and complications in the stage of surgery (p = 1.00). Similarly, at one year, no differences were found with regard to the following: pain around implant (p = 481); infection of implants (p = 491); abnormal radiographic imaging (p = 226); occurrence of undesirable events (p = 1.00); loss of one of the implants (p = 1.00); plaque detection (p = 1.00); bleeding on probing (p = 236); and presence of keratinized mucosa (p = 226). However, a significant difference was found among BGS and CAIS with regard to the number of consultations (p = 0001); number of implants placed (p = 033); and treatment difficulty (p = 0369). Significant differences were found for peri-implantitis (p = 0481) and radiology of craterization (p = 020) in clinical examination at the first year. CONCLUSION: Treatment difficulty and number of consultations were higher for BGS than for CAIS, as well as peri-implantitis and bone craterization at one year, indicating significant differences between the two treatments. However, there were no statistically significant differences between BGS and CAIS regarding the other PROMs, at placement and after one year.

Impact of Cone Beam Computed Tomography Dose in Pre-Surgical Implant Analysis.

OBJECTIVES: Cone-Beam Computed Tomography (CBCT) produces vital information required for the accurate and prudent placement of dental implants. Lack of standardization between CBCT machines may result in unsafe patient exposure to harmful radiation; higher doses are not necessarily associated with improved image quality. AIM: The study aimed to assess the influence of low- and high-dose milliamperage settings on CBCT images for objective and subjective implant planning. METHODS: Two dry skulls (4 hemi-maxillary segments of the maxilla and 4 hemi-maxillary segments of the mandible) were scanned under low (2 mA) and high (6.3 mA) dosage settings using a CBCT (Carestream CS 9300). Cross-sectional slices of both image qualities were evaluated by five expert clinicians, for image quality for implant planning and objective bone measurements. RESULTS: There were no significant differences in bone measurements taken on high or low dose images (p > 0.05). In qualitative image assessments, assessment and image quality for almost all observers were independent of each other. For planning posterior mandibular implant placement, increased dosage improved concordance and kappa values between low and high dose images. CONCLUSION: Reduction in milliamperage did not affect diagnostic image quality for objective bone measurements and produced sufficient intra-rater reliability for qualitative assessment; therefore dose reduction can be achieved without compromising diagnostic decision- making.

Clinical applications and effectiveness of guided implant surgery: a critical review based on randomized controlled trials.

BACKGROUND: Nowadays implant placement protocols are widespread among clinicians all over the world. However, available literature, only partially analyses what can be potential benefits for the clinicians and patients, often focusing just on specific aspects, such as accuracy. The purpose of this review is to compare computer guided implant placement with conventional treatment protocols. METHODS: A search strategy according to the P-I-C-O format was developed and executed using an electronic MEDLINE plus manual search from 2000 up to December 2016. This review included only randomized controlled trials (RCTs) focusing on subjects treated with digital workflow for oral implant placement compared to conventional procedures. Data were extracted from eligible papers and analysed. All kinds of outcomes were considered, even patient-related and economical outcomes. RESULTS: The search strategy revealed 16 articles; additional manual searches selected further 21 publications. Afterwards the evaluation of articles, only two studies could be selected for subsequent data extraction. The two identified RCTs analysed primary outcomes as prosthesis failure, implant failure, biological or prosthetic complications, and secondary outcomes as periimplant marginal bone loss. One RCT evaluated also the duration of treatment, post-surgical progress, additional treatment costs and patient satisfaction. The other RCT focused instead on evaluating eventual improvement of patient's quality of life. In both selected studies, were not observed by the authors statistically significant differences between clinical cases treated with digital protocols and those treated with conventional ones. In one RCT, however post-surgical progress evaluation showed more patients' self-reported pain and swelling in conventional group. CONCLUSIONS: Within the limitation of this review, based on only two RCTs, the only evidence was that implant survival rate and effectiveness are similar for conventional and digital implant placement procedures. This is also confirmed by many other studies with however minor scientific evidence levels. Reduction of post-operative pain, surgical time and overall costs are discussed. Authors believe that scientific research should focus more in identifying which clinical situations can get greatest benefits from implant guided surgery. This should be done with research protocols such as RCT that assess comprehensively the advantages and disadvantages of fully digital surgical protocols.

Horizontal ridge reconstruction of the anterior maxilla using customized allogeneic bone blocks with a minimally invasive technique - a case series.

BACKGROUND: Different surgical procedures have been proposed to achieve horizontal ridge reconstruction of the anterior maxilla; all these procedures, however, require bone replacement materials to be adapted to the bone defect at the time of implantation, resulting in complex and time-consuming procedures. The purpose of this study was to describe how to use a 3D printed hardcopy model of the maxilla to prepare customized milled bone blocks, to be adapted on the bone defect areas using a minimally invasive subperiosteal tunneling technique. METHODS: Cone beam computed tomography (CBCT) images of the atrophic maxilla of six patients were acquired and modified into 3D reconstruction models. Data were transferred to a 3D printer and solid models were fabricated using autoclavable nylon polyamide. Before the surgery, freeze-dried cortico-cancellous blocks were manually milled and adapted on the 3D printed hardcopy models of the maxillary bone, in order to obtain customized allogeneic bone blocks. RESULTS: In total, eleven onlay customized allogeneic bone grafts were prepared and implanted in 6 patients, using a minimally invasive subperiosteal tunneling technique. The scaffolds closely matched the shape of the defects: this reduced the operation time and contributed to good healing. The patients did not demonstrate adverse events such as inflammation, dehiscence or flap re-opening during the recovery period; however, one patient experienced scaffold resorption, which was likely caused by uncontrolled motion of the removable provisional prosthesis. Following a 6 month healing period, CBCT was used to assess graft integration, which was followed by insertion of implants into the augmented areas. Prosthetic restorations were placed 4 months later. CONCLUSIONS: These observations suggest that customized bone allografts can be successfully used for horizontal ridge reconstruction of the anterior maxilla: patients demonstrated reduced morbidity and decreased total surgery time. Further studies on a larger sample of patients, with histologic evaluation and longer follow-up are needed to confirm the present observations.

Different techniques of static/dynamic guided implant surgery: modalities and indications.

For computer-guided surgery a static surgical guide is used that transfers the virtual implant position from computerized tomographic data to the surgical site. These guides are produced by computer-aided design/computer-assisted manufacture technology, such as stereolithography, or manually in a dental laboratory (using mechanical positioning devices or drilling machines). With computer-navigated surgery the position of the instruments in the surgical area is constantly displayed on a screen with a three-dimensional image of the patient. In this way, the system allows real-time transfer of the preoperative planning and visual feedback on the screen. A workflow of the different systems is presented in this review.

Panoramic images versus three-dimensional planning software for oral implant planning in atrophied posterior maxillary: a clinical radiological study.

PURPOSE: The objectives of this radiographic study were to determine to what degree the available residual bone area for implant placement was underestimated on panoramic radiographs (by comparison with multislice computed tomography CT/cone beam CT images combined with planning software) and to what degree the rate of severely resorbed posterior maxillae requiring sinus lift was overestimated on panoramic radiographs (by comparison with planning software in combination with strategic implant placement). MATERIALS AND METHODS: During a 2-year period, every patient who presented for the placement of implants in the posterior maxilla was examined by three practitioners to discuss the treatment plan. When two to three practitioners indicated a sinus lift with creation of a lateral window, a CT scan was performed and examined using dedicated three-dimensional software by a clinician familiar with the Computer Assisted Design/ Computer Assisted Manufacturing (CAD/CAM) implant placement protocol. For each tooth to be replaced, the presence of anatomical features such as anterior or posterior wall, palatal curvature, and septa were examined in view of the placement of an 8-mm or longer implant. RESULTS: One hundred one patients were studied in this case series for the treatment of 135 edentulous spans accounting for 301 missing teeth. After examination of the CT data on the three-dimensional software, 202 teeth (67.1%) could be replaced using a CAD/CAM procedure; 60.7% of the edentulous spans could be completely repaired by a crown or bridge supported by implants. In addition, 67.3% of edentulism with no teeth posterior to the span could be completely repaired using a fixed prosthesis supported by implants. CONCLUSION: This radiological study demonstrates that the use of a panoramic exam for oral implant planning in severely resorbed maxillae overestimates the need for a sinus augmentation procedure when compared with the use of both three-dimensional planning software and strategic implant placement on small remaining bone volume.

Guided implant surgery on oral cancer patients: in vitro study.

PURPOSE: Many oral cancer patients (OCPs) are unable to wear conventional prostheses due to the disease and treatment effects, so they are candidates for oral rehabilitation with osseointegrated implants. A guide suitable for OCPs was designed and tested. METHODS: Image-guided systems based on a custom template for oral implant placement are now widespread among healthy patients, but this has not been extended to OCPs. The EasyGuideT system (Keystone Dental, Burlington, MA, USA) for template stabilization is used on healthy edentulous patients, achieved by bone screws, mini-implants or stereolithography with a bone support. All these systems are invasive and cannot be used in many oral cancer patients. We adapted the EasyGuideT to OCP rehabilitation. The first stage focused on developing a template-positioning system for use on edentulous mandibles that is non-invasive, repeatable, stable on the oral mucosa, consistent with the operating room asepsis, and comfortable for the patient. This repositioning system consists of a cube fiducial marker and an extra-oral support using a facial thermoplastic mask. The mask is linked to the surgical template through the cube. The second stage consisted of direct evaluation of the repositioning system reproducibility, performed on 5 adult cadaver skulls. RESULTS: The translation errors and rotation errors obtained using the modified EasyGuideT system were satisfactory in ex vivo experiments on cadaver skulls. CONCLUSION: A non-invasive repositioning system for image-guided implant surgery on oral cancer patients is clinically feasible using a cube fiducial marker and extra-oral support with a facial thermoplastic mask.

Evaluation of two noninvasive repositioning systems for computer-assisted oral implant surgery in oral cancer patients.

PURPOSE: Reconstructive surgery in oral cancer patients uses thick flaps, which may render the placement of miniscrews for stabilizing radiosurgical templates difficult. The realization of noninvasive systems for the repositioning of surgical templates has been proposed. The present study aimed to assess the clinical usefulness of these noninvasive repositioning systems. MATERIALS AND METHODS: Two noninvasive (ie, without osseous anchorage) repositioning systems (one intraoral, one intra- and extraoral) were tested. They were coupled with a computer-aided system for oral implantation. The criteria for evaluation were: accuracy, cost, time for placement and removal, and six additional subjective criteria (ease of use and production, bulk of the device, patient comfort, stability during surgery, and ergonomics). RESULTS: Nine edentulous patients undergoing surgery to the oral cavity, oropharynx, or pharynx; external radiotherapy of the mandible; or microvascular flap reconstruction were included. Twenty-seven implants were placed in the mandibles of seven patients. For the extraoral system, the angular deviation between planned and achieved position was 6.04 degrees, with differences of 2.14 mm at the tip and 2.16 mm at the base. For the intraoral system, deviations were 5.05 degrees, 1.13 mm, and 1.82 mm, respectively. Subjective criteria were consistent with expected values, especially ease of use, comfort, and ergonomics. CONCLUSIONS: Noninvasive systems remain less accurate than templates stabilized by miniscrews and should be reserved for treating arches in which miniscrews cannot be placed. These methods may be unacceptable in areas where vital structures may be damaged by a misguided implant, and further studies are required. More satisfactory results should be obtained in partially edentulous patients.

Flapless implant surgery using an image-guided system. A 1- to 4-year retrospective multicenter comparative clinical study.

PURPOSE: The aim of this retrospective multicenter clinical study was to compare the survival rate of dental implants placed with two different surgical procedures: (1) a flapless surgical procedure using an image-guided system (IGS flapless protocol) and (2) the conventional technique (open flap without IGS) with a computed tomography scan. MATERIALS AND METHODS: Between 2001 and 2004, 552 implants were placed in 169 patients by six practitioners who used both protocols to restore completely and partially edentulous arches: 271 of them were placed with the IGS flapless protocol (test group) and 281 with the conventional procedure (control group). Each implant was categorized as "survival" or "failure" after 1 to 4 years of follow-up after prosthesis implantation. A preoperative classification was used to evaluate the anatomic features of each case. There was initially no possible comparison between these two groups because of the indication bias relative to the retrospective clinical study data characteristics. After a classic logistic regression analysis, propensity scores were used to reduce this bias: prognosis variables were included in a regression logistic model to define the probability for each implant to be treated with the IGS flapless protocol. Implants showing the same probability were categorized into three classes. The implants were then compared with each other within the same class. RESULTS: After the follow-up period, the cumulative survival rate was 98.57% in the control group and 96.30% in the test group. Whatever the statistical method used, no statistical differences between the two protocols were shown. Transmucosal implant placement showed a survival rate of 97%. Even though the initial conditions were less favorable, the survival rate in the test group was comparable with the standard protocol group. CONCLUSION: Passing an implant through the gum does not interfere with osseointegration. The IGS flapless procedure makes it possible to use the flapless procedure, even though anatomic conditions were initially unfavorable.

Placement of posterior maxillary implants in partially edentulous patients with severe bone deficiency using CAD/CAM guidance to avoid sinus grafting: a clinical report of procedure.

PURPOSE: To provide a detailed presentation of computer-aided design/computer-assisted manufacture guidance in severely resorbed posterior maxillae to place implants in a very limited amount of bone, thus avoiding sinus grafting. MATERIALS AND METHODS: Based on computerized tomography (CT) axial images, implant positions are planned using imaging software. A surgical template is fabricated and drilled with a numerically controlled machine to transfer the planned positions to bone with high accuracy. To avoid sinus grafting, implants can be planned in the anterior or posterior wall and in the septa of the sinus as well as in the palatal curvature. Recipient site preparation is done transgingivally with a drill or with a dedicated bone spreader to increase the amount of bone when necessary. RESULTS: Fifteen resorbed posterior maxillae were treated with a fixed prosthesis supported by a combination of 42 upright and tilted implants. In all cases, implants were placed as planned. Seventeen implants were tilted at a 20- to 35-degree angle with the line perpendicular to the axial CT images. Seven implants were placed in the palatal curvature, 11 implants were close to the anterior wall, and two of them in combination with the palatal curvature. Only one implant was placed close to the posterior wall and two were placed in septa. All patients attended scheduled follow-up visits. During the 4-year observation period, no complications were recorded, no implants were lost, and there was no infection or inflammation. CONCLUSION: This proof-of-concept study suggests that the use of an image-guided system associated with bone spreading for oral implant placement in the atrophic posterior maxilla can be an alternative to sinus grafting.

Accuracy of linear measurement provided by cone beam computed tomography to assess bone quantity in the posterior maxilla: a human cadaver study.

PURPOSE: The aim of this study was to assess, for implant placement in the posterior maxilla, the accuracy of linear measurements provided by cone beam computed tomography (CBCT) using an image intensifier tube and television (TV) chain as an X-ray detector despite a loss of contrast resolution. The NewTom 9000 (Quantitative Radiology, Verona, Italy) was used to explore the posterior maxilla. MATERIALS AND METHODS: Fourteen measurements were taken in three dry maxillaries. On every anatomical site, three fiducial markers were placed on the bony crest to define a plane. Dry maxillaries were submitted to CBCT imaging examination. The maxillaries were then sawn according to the previously defined planes, and bone height and width were assessed using a caliper. The same measurements were taken on images. RESULTS: Clinical analysis demonstrated no difference between real measurements and image measurements. CONCLUSIONS: Although cadaver bone density may not correspond to the density of vital bone, this in vitro study indicates that CBCT images provided by technique using image intensifier tube and TV chain as an X-ray detector are reliable to define the bone volume of the posterior maxilla for the purpose of planning the implant axis.

Effect of flapless surgery on pain experienced in implant placement using an image-guided system.

PURPOSE: The aim of this study was to compare the pain experienced after implant placement with 2 different surgical procedures: a flapless surgical procedure using an image-guided system based on a template and an open-flap procedure. MATERIALS AND METHODS: The study population consisted of 60 patients who were referred for implant placement. One group consisted of 30 patients who were referred for the placement of 80 implants and treated with a flapless procedure. The other group consisted of 30 patients who were referred for the placement of 72 implants with a conventional procedure. Patients were selected randomly. They were requested to fill out a questionnaire using a visual analog scale (VAS) to assess the pain experienced and to indicate the number of analgesic tablets taken every postoperative day from the day of the surgery (DO) to 6 days after surgery (D6). RESULTS: The results showed a significant difference in pain measurements, with higher scores on the VAS with open-flap surgery (P < .01). Pain decreased faster with the flapless procedure (P = .05). The number of patients who felt no pain (VAS = 0) was higher with the flapless procedure (43% at DO versus 20%). With the flapless procedure, patients took fewer pain tablets (P = .03) and the number of tablets taken decreased faster (P = .04). DISCUSSION: Minimally invasive procedures may be requested by patients to reduce their anxiety and the pain experienced and thus increase the treatment acceptance rate. CONCLUSION: With the flapless procedure, patients experienced pain less intensely and for shorter periods of time.

An image-guided system based on custom templates: case reports.

BACKGROUND: With the use of computer-assisted surgery and other modern imaging technologies, the surgeon's procedures have been modified. PURPOSE: The purpose of these case reports is to show the clinical predictability of dental implant placement using an image-guided system. MATERIAL AND METHODS: An acrylic template is made on the patient model. After computed tomographic examination, a treatment plan is established with appropriate software. To fabricate the surgical template, it is necessary to use a dedicated drilling machine. The first osteotomy is achieved through the template with a 2 mm twist drill. The template is then removed, and the osteotomy is completed, followed by implant placement with standard clinical procedures. RESULTS: An excellent predictability was observed between the planned implants and those placed in the two maxillary cases presented: a full upper screw-retained bridge and two single units. CONCLUSIONS: This new technology improves the treatment outcome and optimizes the surgical procedure.

An image-guided system-drilled surgical template and trephine guide pin to make treatment of completely edentulous patients easier: a clinical report on immediate loading.

PURPOSE: An image-guided system has been developed to drill a conventional surgical guide following a preoperative three-dimensional plan for accurate placement of implant on bone. The aim of this study is to illustrate how this system facilitates treatment of completely edentulous patients by modifying both surgical and prosthetic protocols, thereby making flapless surgery possible as well as the preparation of the transitional prosthesis before surgery. MATERIALS AND METHODS: This system was tested on 10 consecutive patients, placing all planned implants without raising the mucoperiosteal flap and with the connection of all implants to pre-angulated abutments. RESULTS: A 1-year follow-up demonstrated stable and properly functioning prostheses in all cases. CONCLUSIONS: This technique can be expected to flourish because implantology makes the highest demands on comfort, precision, and safety.

Reliability of preoperative planning of an image-guided system for oral implant placement based on 3-dimensional images: an in vivo study.

PURPOSE: The purpose of this study was to assess the reliability of the planning software of an image-guided implant placement system based on a mechanical device coupled with a template stabilized on soft tissue during surgery. MATERIALS AND METHODS: Thirty consecutive partially or completely edentulous patients were treated with the image-guided system. For each patient, a study prosthesis was fabricated and duplicated in acrylic resin and served as a scanning template. Axial images were obtained from a computerized tomographic scan and transferred to planning software that provides real 3-dimensional information to plan implant position. Once the final position of the implant was defined, preoperative data such as the size of implants and anatomic complications were recorded using the planning software. The scanning template was then drilled in that exact position by a drilling machine. During surgery, the drilled template was used as a drill guide. After implant placement, intraoperative data were recorded and statistically compared with the preoperative data using the Kendall correlation coefficient for qualitative data and the Kappa concordance coefficient for quantitative data. RESULTS: Agreement between the preoperative and intraoperative data was high for both implant size and anatomic complications. The Kendall correlation coefficient was 0.8 for the diameter and 0.82 for the length. The Kappa concordance coefficient was 0.87 for both dehiscence and bone graft, 0.88 for osteotomy, and 1.0 for fenestration. DISCUSSION: In the few instances where planning was not perfect, implant placement was completed in a clinically acceptable manner. CONCLUSION: The results suggest that the image-guided system presented is reliable for the preoperative assessment of implant size and anatomic complications. It may also be reliable for flapless surgery.

Precision of transfer of preoperative planning for oral implants based on cone-beam CT-scan images through a robotic drilling machine.

In this study, an image-guided system for oral implant placement was assessed. A specially designed mechanical tool has been elaborated to transfer the preoperative implant axis planned on 3-dimensional imagery into a surgical template by a numerically controlled drilling machine. The main drawback of image-guiding systems is the use of preoperative computed tomography, which is expensive and delivers high radiation doses. Therefore, in this study the image-guiding system was coupled with a cone-beam tomograph that significantly decreased both cost and radiation doses. Three edentulous models were used. To determine the accuracy of the system, the ability of a 1.8-mm diameter drill to enter a 2.0-mm diameter, 10-mm-long titanium tube inserted on the model with no contact was verified. Because the drill entered the tubes with no contact and went beyond the end of the tube, the transfer error was less than 0.2 mm for translation and less than 1.1 degrees for rotation. The method presented here is low cost and high precision compared to other technological solutions such as tracking. Further assessment in the surgical field should lead to daily use of this system for flapless surgery, to prepare a prosthesis prior to surgery for immediate loading, to reduce risk of injuring critical anatomical structures and to eliminate manual placement error.