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Objectives: Procedures in oral and maxillofacial surgery bear a high risk of nerve damage. Three-dimensional imaging techniques can optimize surgical planning and help to spare nerves. The aim of this study was to investigate the diagnostic value of a 1.5 T magnetic resonance imaging (MRI) scanner with a dedicated dental signal amplification coil for the assessment of nerves in the oral cavity as compared with cone beam computed tomography (CBCT)., Methods: Based on 6 predefined criteria, the assessability of the inferior alveolar and nasopalatine nerves in CBCT and MRI with a dedicated 4-channel dental coil were compared in 24 patients., Results: Compared with CBCT, MRI with the dental coil showed significantly better evaluability of the inferior alveolar nerve in the sagittal and axial plane and the nasopalatine nerve in the axial plane. In the sagittal plane; however, the assessability of the nasopalatine nerve was significantly better in CBCT as compared with MRI. Yet, pertaining to overall assessability, no significant differences between modalities were found., Conclusions: In this pilot study, it can be reported that 1.5- T MRI with a dedicated dental coil is at least equivalent, if not superior, to CBCT in imaging nerve structures of the stomatognathic system., Clinical Relevance: Preoperative, 3-dimensional images are known to simplify and refine the planning and execution of operations in maxillofacial surgery. In contrast to computed tomography and CBCT, MRI does not cause radiation exposure while enabling visualization of all relevant hard and soft tissues and, therefore, holds an advantage over well-established techniques., Competing Interests: N.G.H. is a speaker at the bureau of Philips Healthcare; received research support from Philips Healthcare; and consultancy for Bristol-Myers Squibb. The remaining authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

The greatest key to successful implant therapy is proper placement of the implant in the jaw bone. The key to proper placement is careful preoperative planning. When planning implant treatment, it is important to take the relevant anatomical features and their later prosthetic consequences into account. This is done using a radiographic template of the planned restoration, which until now had to be made by a dental technician. The radiographic template must be inserted in the patient's mouth during radiographic imaging so that the dentist can visualize the prosthetic plan. Implant planning is thus performed according to the backward planning principle. In the novel, fully digital approach to dental implant planning presented here, the prosthetic proposal is designed using computer-aided design software and integrated into a three-dimensional radiograph. This article explains how the technology works and reviews the available data. In addition, the clinical workflows for the SiCAT Optiguide and Sirona Cerec Guide virtual implant planning methods will be described and compared with conventional implant planning methods. Finally, the indications and countraindications for the two methods will be discussed.

Objectives: To evaluate the potential influence of different cone-beam computed tomography (CBCT) devices on the transfer accuracy of an open-source system for computer-aided implantology (CAI)., Material and Methods: A total of 108 implants in 18 partially edentulous patient-equivalent models were planned and fully guided implants were inserted using an open-source CAI system with three different CBCT devices. After follow-up CBCT and fiducial marker-matching procedure, linear horizontal, vertical, and maximal three-dimensional deviations, as well as angle deviations between the virtual planning data and the surgical results were calculated. Variance analysis was carried out to prove whether or not the observed differences between the CBCT devices were statistically significant., Results: The observed mean three-dimensional deviation rates between virtually planned and achieved implant positions varied by around 400 μm (45%) at the implant's base and around 540 μm (50%) at the implant's tip in dependence to the applied CBCT device. Mean vertical deviations varied around 370 μm (76%) at the implant's base and 350 μm (69%) at the implant's tip, whereas axes deviations varied around 0.81° (40%) between the three investigated CBCT devices. Except for the axes deviations and the horizontal linear deviations at the implants base, observed differences reached significance level between the CBCT devices., Conclusions: Until now, the potential influence from different CBCT devices on the transfer accuracy of CAI systems has not yet been investigated. Data from the present study confirm for the first time the in vitro CBCT device dependency on the transfer accuracy of CAI systems reaching up to axes deviations of 0.6 angle degree and linear deviations around half a millimeter., (© 2011 John Wiley & Sons A/S.)

Purpose: Implant placement in the edentulous anterior mandible is frequently performed to stabilize prosthetic superstructures. The position of the inferior alveolar nerve (IAN), especially in an atrophic mandible, has to be considered to position implants properly. In this study, the prevalence of looping of the IAN was retrospectively determined to assess the need for imaging prior to implant placement in the anterior mandible., Materials and Methods: Cone beam computed tomography scans of consecutive patients were evaluated to assess the prevalence and size of IAN looping. The results were compared with respect to patient age and sex as well as degree of atrophy and bone height at the mental foramen., Results: Scans of 1,010 patients were obtained. IAN loops were found in 31% of the patients, with a significantly higher prevalence in male patients (33.1%) than in female patients (28.1%). The average size of loops was 1.4 ± 0.70 mm, with a maximum of 4.6 mm. For male patients, the average loop size was 1.6 ± 0.74 mm (maximum 4.6 mm), and for female patients an average dimension of 1.4 ± 0.63 mm (maximum 4.4 mm) was recorded. This difference was significant (t test). A significant difference with respect to the various classes of atrophy up to class 4 was not found., Conclusion: Loops of the IAN occur in about one third of patients and vary in size from 0.7 to 4.6 mm. Large anterior loops put the IAN at risk when interforaminal implants are placed. Either a sufficient safety distance or three-dimensional imaging procedures should be used to detect loops and locate the incisive canal, which could be harmed during the interforaminal implant placement.

Objective: The aim of this study was to assess the prevalence of pathologic findings in the maxillary sinus by using cone-beam computerized tomography (CBCT)., Study Design: One thousand twenty-nine consecutive CBCT scans were retrospectively inspected for pathologic findings in the maxillary sinus by 3 observers. Findings were differentiated by mucosal thickening, partial opacification with liquid accumulation, total opacification, and polypoidal mucosal thickening. Position and diameter of the maxillary sinus ostium were assessed. Correlations for pathologic findings and the factors of age and gender were calculated. Patients with clinical manifestations of sinusitis or total opacification in either sinus were reevaluated., Results: A total prevalence for pathologies in the maxillary sinus of 56.3% was found in this study. The most frequent pathology was mucosal thickening. Patients >60 years of age showed significantly more pathologies in the maxillary sinus (P = .02), and male patients showed significantly more pathologies than female patients (P = .01). Clinical signs of sinusitis could be confirmed on CBCT images for all patients., Conclusions: Pathologies in the maxillary sinus are frequently found in CBCT imaging and have to be treated or followed-up accordingly. CBCT is applicable for diagnosis and treatment planning of clinically present sinusitis., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Objective: The objective of this study was to evaluate cone-beam CT (CBCT) diagnoses of sialoliths in the major salivary glands., Study Design: Twenty-nine CBCT images containing salivary calculi were retrospectively evaluated for image quality and artifact influence. Additionally, the reproducibility of calculus measurement and the differences between CBCT measurements and ultrasonography (US) and histomorphometry (HM) measurements were determined. Diagnostic sensitivity and specificity calculations were based on the observations of 3 masked clinicians, who reviewed a total of 58 CBCT volumes., Results: Salivary calculi were sufficiently visualized in all patients. Metal artifacts were detected in images of 7 patients, and movement artifacts in 2. CBCT calculi measurements were highly reproducible, with mean differences of less than 350 microm. Mean CBCT measurements of calculi diameters differed from mean US measurements by approximately 500 microm and differed from mean HM measurements by approximately 1 mm. For calculus diagnoses, the mean sensitivity and specificity were both 98.85%., Conclusion: Although poor image qualities and artifacts can reduce diagnostic information, salivary calculi can be evaluated adequately with CBCT. CBCT measurements of calculi are highly reproducible and differ little from measurements made with US and HM. Diagnostic sensitivity and specificity levels with CBCT are as high as or higher than those obtained with other diagnostic methods. Because of its high diagnostic-information-to-radiation-dose ratio, CBCT is the preferable imaging modality for salivary calculus diagnosis., (Copyright (c) 2010 Mosby, Inc. All rights reserved.)

Purpose: Surgical complications during sinus floor elevation are frequently caused by septa in the maxillary sinus. In this study, the prevalence of septa was retrospectively determined via three-dimensional imaging to assess the necessity for appropriate imaging prior to sinus floor elevation., Materials and Methods: The cone-beam computed tomography scans of 1,029 consecutive patients were evaluated to assess the prevalence of septa, taking into account patient age and sex as well as the number and orientation of septa and their locations. If septa were present, the height was measured and the orientation was determined., Results: Septa were found in 47% of patients and 33.2% of sinuses. There was no statistical difference in prevalence with respect to age, sex, or side. Most patients with septa showed one septum in one sinus (24.6%); 13.7% showed one septum in each sinus. Other combinations (up to three septa per sinus) were found in 8.7% of patients. Septa were most commonly located in the first molar region (256 septa), followed by the second molar region (225 septa), the third molar region (144), second premolar region (136), the first premolar region (44), and the canine region (5). The mean septal height was 11.7 +/- 6.08 mm for septa in a sagittal orientation (n = 206, 25.3%; maximum height of 37 mm) and 7.3 +/- 5.08 mm for those oriented transversely (n = 608, 74.7%; maximum height of 36 mm). The variance was larger for the sagittal orientation group (37.03 mm) than for transversely oriented septa (25.9 mm)., Conclusion: Septa were found in 47% of the patients in this sample. Appropriate imaging prior to performing sinus surgery seems justified, since complications and the success rate of sinus floor elevation are clearly related to the presence of septa. Int J Oral Maxillofac Implants 2010;25:258-265.

Objectives: This in vitro study assessed the visualization quality of the periodontal ligament space in cone-beam computerized tomography (CBCT) compared with intraoral radiographs (CR)., Study Design: A phantom mimicking variable periodontal ligament spaces (0-0.42 mm) was radiographed using CBCT and CR. Fifteen datasets of each modality were randomly mixed and presented twice to 19 experienced examiners and once to 19 inexperienced examiners., Results: Zero-millimeter gaps were recognized in 84.4% of CBCT and in 81.6% of CR images. On CBCT scans, gaps of 0.19 mm were identified with an accuracy of 93%-100% compared with 70.2%-81.7% using CR. Experienced examiners recognized gaps of >or=0.19 mm on CBCT repeatedly with nearly 100% accuracy., Conclusion: Compared with CR, CBCT provides better visualization of simulated periodontal ligament space in this phantom., (Copyright (c) 2010 Mosby, Inc. All rights reserved.)

Implant treatment increasingly focuses on the reduction of treatment time and postoperative impairment. The improvement of 3D dental diagnosis by ConeBeam computed tomography allows detailed preparation for the surgical placement of dental implants under prosthetic considerations. While the first generation of implant planning software used high-contrast multislice computed tomography, software that has been specifically designed for ConeBeam computed tomography is now available. Implant placement can be performed using surgical guides or under the control of optical tracking systems. Surgical guides are more commonly used in private office owing to their availability. The accuracy for both techniques is clinically acceptable for achieving implant placement in critical anatomical indications. When using prefabricated superstructures and in flapless surgery, special abutments or an adjusted workflow are still necessary to compensate misfits of between 150 and 600 microm. The proposition to ensure proper implant placement by dentists with limited surgical experience through the use of surgical guides is unlikely to be successful, because there is also a specific learning curve for guided implant placement. Current and future development will continue to decrease the classical laboratory-technician work and will integrate the fabrication of superstructures with virtual treatment planning from the start.

Objectives: To evaluate the accuracy of the first integrated system for cone-beam CT (CBCT) imaging, dental implant planning and surgical template-aided implant placement., Materials and Methods: On the basis of CBCT scans, a total of 54 implant positions were planned for 10 partially edentulous anatomical patient-equivalent models. Surgical guides were ordered from the manufacturer (SICAT). Two different types of guidance were assessed: for assessment of the SICAT system inherent accuracy vendor's titanium sleeves of 2 mm internal diameter and 5 mm length were utilized for pilot drills. The guide sleeves of the NobelGuide system were implemented for fully guided surgery and implant insertion. Deviations perpendicular to the implant axes at the crestal and apical end, as well as the angle deviations between the virtual planning data and the surgical results, were measured utilizing a follow-up CBCT investigation and referential marker-based registration., Results: The SICAT system inherent mean deviation rates for the drilled pilot osteotomies were determined to be smaller than 500 mum even at the apical end. Mean angle deviations of 1.18 degrees were determined. Utilizing the NobelGuide sleeve-in-sleeve system for fully guided implant insertion in combination with the investigated template technology enabled to insert dental implants with the same accuracy. Crestal deviations, in general, were significantly lower than the apical deviations., Conclusion: Although hardly comparable due to different study designs and measurement strategies, the investigated SICAT system's inherent accuracy corresponds to the most favourable results for computer-aided surgery systems published so far. In combination with the NobelGuide surgical set for fully guided insertion, the same accuracy level could be maintained for implant positioning.

Objective: The aim was to determine the influence of patient age, gender, body mass index (BMI), amount of dental restorations, and implants on image quality of cone-beam computerized tomography (CBCT)., Methods: Fifty CBCT scans of a preretail version of Galileos (Sirona, Germany) were investigated retrospectively by 4 observers regarding image quality of 6 anatomic structures, pathologic findings detection, subjective exposure quality, and artifacts. Patient age, BMI, gender, amount of dental restorations, and implants were recorded and statistically tested for correlations to image quality., Results: A negative effect on image quality was found statistically significantly correlated with age and the amount of dental restorations. None of the investigated image features were garbled by any of the investigated influence factors., Conclusions: Age and the amount of dental restorations appear to have a negative impact on CBCT image quality, whereas gender and BMI do not. Image quality of mental foramen, mandibular canal, and nasal floor are affected negatively by age but not by the amount of dental restorations. Further studies are required to elucidate influence factors on CBCT image quality.

Objective: The removal of third molars requires information about the relative position of the root tips and the mandibular nerve. The diagnostic value of conventional radiologic procedures using a panoramic radiograph and symmetrical PA cephalometric radiograph (PAN&PA) was compared with that of a cone-beam volumetric imaging (CBVI) device (Galileos; Sirona, Bensheim, Germany)., Study Design: Six observers evaluated 30 PAN&PA and 30 CBVI for the position of root tips. Diagnostic information was rated from 1 to 5 (excellent to poor)., Results: With PAN&PA, 3 times more scans showed nondetectable information for horizontal position compared with CBVI. The diagnostic information in the vertical dimension received a median rating of 2 (good) for CBVI and for PAN & PA; for the horizontal dimension, CBVI received a median rating of 2 (good), compared with a significantly worse median rating of 3 (sufficient) for PAN & PA (P = .000). The variance was highest for the horizontal dimension with PAN & PA (1.27)., Conclusion: These findings indicate that cone-beam technology improves the localization of third molar for presurgical planning.

Objectives: To compare the diagnostic quality of multiplanar reformations generated by a newly developed cone beam device with the diagnostic quality of multiplanar reformations obtained using a state of the art multidetector row CT scanner., Methods: Digital volume tomograms (DVTs) were obtained with the prototype of GALILEOS (Sirona Dental Systems Inc., Bensheim, Germany), a newly developed compact-sized cone beam machine with a scan volume of 15 x 15 x 15 cm. CT scans were performed for comparison with two 16-detector row CT scanners. The study included 30 image pairs obtained from the same patients. The multiplanar reformations in axial, coronal and sagittal planes were subjectively assessed by 3 observers using a 1(excellent)-5(poor) scale on 35 weighted criteria including findings detection, image quality and visualization of several anatomical structures., Results: There was no statistically significant difference between DVT and CT in cumulative values expressing the diagnostic quality of the reformations (P = 0.071). The interobserver agreement was better with CT than with DVT. Findings detection and the visualization of the majority of anatomical structures within the mandibulomaxillary area were ranked at the same level for DVT as with CT., Conclusions: The diagnostic quality of multiplanar reformations can be considered the same in both devices. Although sharpness, noise level and contrast resolution do not reach the level of CT, DVT images proved statistically not inferior for the detection of lesions which may be adequately depicted by both imaging modes.