Comparing the precision of panoramic radiography and cone-beam computed tomography in avoiding anatomical structures critical to dental implant surgery: A retrospective study

Bibliometric analysis and diagnostic efficacy of cone-beam computed tomography studies published in Imaging Science in Dentistry from 2011 to 2022

Purpose

This bibliometric analysis aimed to provide a comprehensive overview of the characteristics, trends, and level of diagnostic efficacy of studies on cone-beam computed tomography (CBCT) published in Imaging Science in Dentistry (ISD) from 2011 to 2022.

Materials and Methods

Publications related to CBCT identified in the electronic collection of ISD were selected according to eligibility criteria by 2 independent reviewers who collected data on the characteristics of the articles (year, authors, and country). The type and topic of studies were analyzed using VOSviewer v.1.6.18 (Centre for Science and Technology Studies, Leiden University, Leiden, Netherlands). The research articles were classified according to the hierarchical scale of diagnostic efficacy.

Results

Of the 236 articles included, most were from South Korea and Brazil. Bong-Hae Cho and Yun-Hoa Jung were the most prolific authors on the topic of CBCT. The most frequently published types of studies were cross-sectional and laboratory-based. The most popular topics WERE related to the diagnosis of pathologies and/or alterations, as well as anatomical variations. On the diagnostic efficacy scale, most studies were rated level 1 (technical efficacy) or 2 (diagnostic accuracy efficacy).

Conclusion

A steady increase was observed in publications related to CBCT, which are of both clinical and academic interest. The trends in these publications were analyzed, revealing that most are cross-sectional studies primarily exploring the capabilities of CBCT in diagnosing pathologies and/or changes in the oral and maxillofacial complex. These studies were typically classified as level 1 or 2 on the diagnostic efficacy scale.

Nasal cavity perforation by implant fixtures: case series with emphasis on panoramic imaging of nasal cavity extending posteriorly

The nasal cavity is an important landmark when considering implant insertion into the anterior region of the maxillary arch. The perforation of implants into the nasal cavity may cause complications, such as implant migration, inflammation, or changes in nasal airflow; thus, precise assessment of the nasal cavity is mandatory.Three cases of nasal cavity perforation by dental implants are presented, including one case of implant fixture migration into the nasal cavity. On panoramic radiographs of the patients, the following common features were observed: the horizontal radiopaque line of the hard palate was observed to be inferior to or similar to that of the antral floor and the bone between the lateral wall of the nasal cavity and the medial wall of the maxillary sinus was emphasized in a triangular shape.When the maxillary sinus is small and alveolar bone resorption is severe, panoramic evaluation may cause overestimation of the available residual bone, particularly in the maxillary canine/premolar region. Therefore, the residual bone should be reevaluated three-dimensionally to measure the exact bony shape and volume.

Digital panoramic radiography and CBCT as auxiliary tools for detection of low bone mineral density in post-menopausal women: a cross-sectional study

BACKGROUND

Osteoporosis is a chronic, multifactorial skeletal disease that occurs especially in women following a decrease in estrogen levels and decrease in bone mineral density. The aim of this study was to evaluate the relationship between qualitative and quantitative indexes in panoramic radiographs and quantitative indexes in CBCT images with femoral and vertebral BMD in postmenopausal women.

METHODS

This comparative cross-sectional study was performed on postmenopausal women aging 40 to 80 years attending for obtaining either panoramic radiograph or mandibular CBCT scan. Dual energy X-ray absorptiometry (DEXA) was performed from the femur and lumbar vertebra. Quantitative parameters of mental index (MI), panoramic mandibular index (PMI), antegonial index (AI) as well as qualitative parameters of mandibular cortical index (MCI) and trabecular bone pattern (TP) were evaluated in panoramic radiographs. Quantitative parameters computed tomography mandibular index (CTMI), computed tomography index (inferior) [CTI(I)] and computed tomography index (superior) [CTI(S)] were analyzed in CBCT images. Kolmogorov-Smirnov tests and Pearson correlation coefficient were used (α = 0.05).

RESULTS

In individuals with panoramic radiography, statistically significant correlations were observed between MI with vertebral and femoral T-score, AI with vertebral and femoral T-score (except for the right AI with femoral T-score), and TP with vertebral and femoral T-score (p < 0.05). In the group with CBCT scans, the correlations between CTMI with vertebral and femoral T-score, CTI(I) with vertebral and femoral T-score, and CTI(S) with vertebral and femoral T-score were statistically significant (p < 0.05).

CONCLUSIONS

in CBCT images, quantitative indexes of CTMI, CTI(I), and CTI(S), and in panoramic images, quantitative indexes of MI and AI and qualitative index of TP can be used to predict the possibility of osteoporosis in postmenopausal women.

Are maxillary sinus variations related to maxillary sinus diameters?

OBJECTIVES

The reasons why the maxillary posterior region is challenging for dentists are its structure and anatomical variations. For this reason, it is necessary to have complete knowledge about the anatomy of this region. In dentistry, necessary information for the desired evaluation in this region can be provided by CBCT. The fact that it provides a three-dimensional evaluation and has measurement reliability emphasizes its importance in surgical applications. The septa, haller cell, and accessory ostium are variations of the maxillary sinus. There are few studies in the literature examining the relationship between maxillary sinus diameters and its variations. The aims of this study are to determine the prevalence of maxillary sinus variations and the average of maxillary sinus diameters, to examine their relationships according to age and gender, and to evaluate the effects of maxillary sinus diameters on variations.

METHODS

In this retrospective study, CBCT images of 212 patients were examined. The examined CBCT images were analysed and recorded in more than one section. Descriptive statistics, chi-square tests, independent t test, one-way Anova tests were used to evaluate the data.

RESULTS

As a result, a statistically significant difference was observed between the variations, gender and age groups in terms of morphometric characteristics of the maxillary sinus. The most common variation was observed to be accessory ostium.

CONCLUSIONS

The rate of patients with at least one anatomical variation was 77.8%. For this reason, a detailed analysis should be performed to avoid complications before surgical procedures are performed in the area.

Automated measurement for image distortion analysis in 2D panoramic imaging of dental CBCT system: A phantom study

INTRODUCTION

The daily image quality assessment involves large datasets that consume a lot of time and effort. This study aims to evaluate a proposed automated calculator for image distortion analysis in 2-dimensional (2D) panoramic imaging mode for a dental cone beam computed tomography (CBCT) system in comparison with present manual calculations.

METHODS

A ball phantom was scanned using panoramic mode of the Planmeca ProMax 3D Mid CBCT unit (Planmeca, Helsinki, Finland) with standard exposure settings used in clinical practice (60 kV, 2 mA, and maximum FOV). An automated calculator algorithm was developed in MATLAB platform. Two parameters associated with panoramic image distortion such as balls diameter and distance between middle and tenth balls were measured. These automated measurements were compared with manual measurement using the Planmeca Romexis and ImageJ software.

RESULTS

The findings showed smaller deviation in distance difference measurements by proposed automated calculator (ranged 3.83 mm) as compared to manual measurements (ranged 5.00 for Romexis and 5.12 mm for ImageJ software). There was a significant difference (p < 0.05) on the mean measured ball diameter between automated and manual measurement. For ball diameter measurement, there is a moderate positive correlation between automated measurement with the manual measurements (r = 0.6024 and r = 0.6358 for Romexis and ImageJ, respectively). However, there is a negative correlation between automated measurement for the distance difference with manual methods (r = -0.3484 and r = -0.3494 for Romexis and ImageJ, respectively). There was a good approximation between automated and ImageJ measurement of ball diameter in comparison to reference value.

CONCLUSION

In conclusion, the proposed automated calculator provides faster method with an accurate and acceptable results for daily-basis image quality test in dental panoramic mode of a Dental CBCT imaging system in comparison to current manual method.

IMPLICATIONS FOR PRACTICE

An automated calculator is recommended for image distortion analysis on phantom images in routine image quality assessment for dental panoramic mode of Dental CBCT imaging system that may involve analysis of large image datasets. It offers improvement in routine image quality practice in term of time and accuracy.

Evaluation of the contour of edentulous jaw sections in the transversal plane and the buccolingual vertical-level disparity in CBCT and panoramic radiography images: a retrospective comparative study

PURPOSE

This study investigates whether edentulous jaw sections in the planned implant position exhibit jaw contours funnel-shaped or exhibit pronounced retraction of the jaw (unusual jaw contours) in the transversal plane of the three-dimensional (3D) images, not visible in two-dimensional (2D) images.

METHODS

A total of 335 patients with an edentulous section of the jaw that required dental implants were selected. Anonymised radiologic patients' data were collected, comprising cone-beam computed tomography (CBCT) images of the edentulous jaw sections. In the first stage, unusual jaw contours were examined, including funnel-shaped or pronounced retraction of the jaw and hypodense regions with an undercut and/or bone deficit. In the second stage, the variation in the height of the alveolar ridge between the lingual and buccal contour in the edentulous jaw sections was assessed.

RESULTS

The CBCT images of an unusual jaw contour were observed in 8 cases (2.4%) in the maxilla on the left and 10 cases (3%) in the maxilla on the right. In the mandible, a jaw contour deviates in 39 cases (12.1%) on the left side and 39 cases (12.1%) on the right side. A height difference was detected in the upper jaw in 307 cases and the lower jaw in 265 cases. The discrepancy was 2.09 mm (± 2.25 mm) in the maxilla and 3.97 mm (± 3.45 mm) in the mandible.

CONCLUSIONS

The CBCT scan provides useful information to avoid complications in the preoperative planning phase and surgical planning in implant dentistry.

Is Intraoral Scanning Accurate to Evaluate Dental Implant Position? An In-Vitro Study

PURPOSE

The position of dental implants is generally verified through imaging exams, even though its use exposes patients to radiation. Intraoral scanning (IOS) may be a suitable alternative to using radiographic imaging to verify implant position. Using polyurethane jaw models, the purpose of this in-vitro study was to measure and compare implant positions determined by IOS and cone-bean computed tomography (CBCT).

METHODS

One hundred twenty implants were installed in 30 edentulous polyurethane jaws, 4 dental implants in each prototype. Four scanbodies were attached to the implants, and a scanning of each mandible was acquired using an intraoral scanner (CS 3600). All prototypes were also submitted to CBCT. Then, the 3D scan files in STL (Standard Tessellation Language) format were superimposed on the DICOM (Digital Imaging and Communications in Medicine) images of the tomographic mandibles. The accuracy of IOS was evaluated by the metric analyses of deviations between the position of the implants projected by the IOS versus the detected tomographically, in which CBCT served as the gold standard, using a free software for digital planning (Bluesky 4 - Grayslake, IL, USA). The following measures were analyzed: radial deviations at the shoulder (Xc) and at the apex of the implants (Xa), height deviation (Xh) and axial deviation. Bland-Altman and a paired t-test were applied to verify the reproducibility between measurements and a t-test for a mean was applied to compare the measurements with zero value.

RESULTS

The results showed Xc and Xa deviation means of 0.14 ± 0.09 mm and 0.12 ± 0.12 mm, respectively. The Xh mean was 0.2 ± 0.12 mm and the axial deviation mean was 0.71° ± 0.66°. T-test showed a statistically significant difference when the 4 means were compared to zero value, represented by the CBCT (P < .0001).

CONCLUSIONS

There was a statistically significant difference IN the scanned measures compared to CBCT as the standard, but the differences may not be clinically significant. The IOS utilization to evaluate the position of dental implants is a radiation-free and reproducible method, with the advantage of not generating metal artifacts. Further clinical studies are needed to validate this new method of postoperative evaluation.

A diagnostic accuracy study on an innovative auto-edge detection technique for identifying simulated implant fractures on radiographic images

Implant fracture is a rare but devastating complication of treatment in partially or fully edentulous patients which requires prompt diagnosis. Nevertheless, studies on defining the most accurate technique for the detection of implant fractures are lacking. In the present study, the Canny edge detection algorithm was applied on multiple radiographic modalities including parallel periapical (PPA), oblique periapical (OPA), and cone beam CT (CBCT) with and without metal artifact reduction (MAR) to examine its accuracy for diagnosis of simulated implant fractures. Radiographs were taken from 24 intact implants and 24 implants with artificially created fractures. Images were evaluated in their original and Canny formats. The accuracy of each radiograph was assessed by comparison with a reference standard of direct observation of the implant. The greatest area under the receiver operating characteristic curve belonged to Canny CBCT with MAR (0.958), followed by original CBCT with MAR (0.917), original CBCT without MAR = Canny CBCT without MAR = Canny OPA (0.875), Canny PPA (0.833), original PPA = original OPA (0.792), respectively. The Canny edge detection algorithm is suggested as an innovative method for accurate diagnosis of clinically suspected implant fractures on CBCT and periapical radiographies.

Comparison of the Efficacy of the Panoramic and Cone Beam Computed Tomography Imaging Methods in the Surgical Planning of the Maxillary All-On-4, M-4, and V-4

This study is aimed at analyzing the difference between the measurements made according to certain anatomical signs of the maxillary jaw using panoramic radiography and cone beam computed tomography (CBCT) to decide whether to use all-on-4, M-4, or V-4 configuration to prevent complications caused by incorrect measurements during the presurgical planning stage of the placement of implants in the all-on-4 technique. A retrospective study was conducted with 50 patients with upper edentulous jaws suitable for the all-on-4 technique, who underwent preoperative panoramic radiography and cone beam computed tomography evaluation for dental implant surgery. The shortest vertical distances between anatomical structures were measured. Measurements were made independently by two oral and maxillofacial surgeons, one experienced and the other inexperienced. A statistically significant difference was found between the mean values according to gender (p=0.045). When the measurements made by the experienced surgeon and the inexperienced surgeon were compared, there was no significant difference between panoramic radiography and cone beam computed tomography. In situations where bone measurements are required for deciding on all-on-4 or one of its configurations (M-4 and V-4), it was found that panoramic radiography gives significantly incorrect results compared to cone beam computed tomography (p<0.05). Cone beam computed tomography is more reliable than panoramic radiography and eliminates the margin of error in the planning of all-on-4 or its variations to be made by either an experienced or an inexperienced oral surgeon.

A Review of Doses for Dental Imaging in 2010-2020 and Development of a Web Dose Calculator

Dental imaging is one of the most common types of diagnostic radiological procedures in modern medicine. We introduce a comprehensive table of organ doses received by patients in dental imaging procedures extracted from literature and a new web application to visualize the summarized dose information. We analyzed articles, published after 2010, from PubMed on organ and effective doses delivered by dental imaging procedures, including intraoral radiography, panoramic radiography, and cone-beam computed tomography (CBCT), and summarized doses by dosimetry method, machine model, patient age, and technical parameters. Mean effective doses delivered by intraoral, 1.32 (0.60-2.56) μSv, and panoramic, 17.93 (3.47-75.00) μSv, procedures were found to be about1% and 15% of that delivered by CBCT, 121.09 (17.10-392.20) μSv, respectively. In CBCT imaging, child phantoms received about 29% more effective dose than the adult phantoms received. The effective dose of a large field of view (FOV) (>150 cm2) was about 1.6 times greater than that of a small FOV (<50 cm2). The maximum CBCT effective dose with a large FOV for children, 392.2 μSv, was about 13% of theeffective dose that a person receives on average every year from natural radiation, 3110 μSv. Monte Carlo simulations of representative cases of the three dental imaging procedures were then conducted to estimate and visualize the dose distribution within the head. The user-friendly interactive web application (available at http://dentaldose.org) receives user input, such as the number of intraoral radiographs taken, and displays total organ and effective doses, dose distribution maps, and a comparison with other medical and natural sources of radiation. The web dose calculator provides a practical resource for patients interested in understanding the radiation doses delivered by dental imaging procedures.

[Use of diagnostic modalities for dentofacial imaging in forensic dentistry. Literature review]

Objective

To describe the use of diagnostic modalities for dentofacial imaging in forensic dentistry.

Materials and Methods

A scientific search was carried out in the PubMed, Google Academic, and SciELO databases with the keywords "Dentofacial Imaging", "Panoramic Radiography", "Lateral Cephalogram", "Cone Beam Computed Tomography (CBCT)", "Digital Radiography", and "Forensic Dentistry". Forty-eight recently dated articles published in English were selected, seeking information to describe the use of diagnostic modalities pertaining to dentofacial imaging in forensic dentistry.

Results

The most relevant diagnostic modalities of dentofacial imaging for forensic dentistry include panoramic radiography, lateral skull radiography, posterior-anterior skull radiography and cone beam computed tomography.

Conclusions

The modalities described, together with morphometric analyses, allow forensic dentists to identify a corpse, estimate age, sex, and even facilitate forensic facial reconstruction for identification purposes.

Successful dental implantation: evaluating the accuracy of horizontal and vertical measurements on panoramic radiographs using dental implants as reference objects

BACKGROUND

The purpose of this study was to calculate the regional distortions in digital panoramic radiographs and to evaluate the accuracy of panoramic radiography in dental implant treatments. Also, it was aimed to determine the vertical and horizontal distortion rate of digital panoramic device by using dental implants as reference objects.

METHODS

A retrospective study was designed and implemented, based on the analysis of panoramic radiography records. Postoperative images of implant treatments which did not required bone augmentation procedures included in the study. Measurements were made on images of 554 implants placed, adjacent to at least one tooth in different regions of the jaws. The distortion rate was calculated by determining the ratio of the radiographic dimensions of the implants to the actual implant sizes.

RESULTS

The distortion rate of the digital panoramic device was determined as 1.11 vertically and 1.81 horizontally. Vertically, radiographic measurements were calculated lower than the actual implant lengths as 0.95 mm in the anterior, 0.70 mm in the premolar and 0.60 mm in the molar regions. Horizontally, radiographic measurements were calculated lower than the actual implant width as 0.50 mm in anterior and molar regions and 0.60 mm in premolar region, respectively. These differences were statistically significant (p < 0.001).

CONCLUSIONS

Considering the results of the device and regional distortion rates, it has been shown that digital panoramic radiography is an effective method to evaluate the existing bone height, especially in the posterior regions of the jaws, when a safe distance to the anatomical structures is maintained.

Evaluation of the Metal Artifact Caused by Dental Implants in Cone Beam Computed Tomography Images

Statement of the problem: The presence of a metal object such as dental implants in the scan field may cause artifacts on the cone-beam computed tomography (CBCT) images, which can reduce the diagnostic quality and accuracy of images. Purpose: The aim of this in vitro study was to compare the severity of implant-induced metal artifacts on CBCT images. Materials and method: To this end, a dry human mandible and a maxilla were selected, then two Roxolid and two Zirconium fixtures with different diameters were placed in the central incisor and first molar sockets and fixed with dental wax. The mandible and maxilla were placed in the simulated phantom for soft tissue, and the occlusal plane was adjusted parallel to the horizon. Images were taken at standard and high resolutions using two CBCT units. The CBCT gray values were measured in three longitudinal sections of the fixture (cervical, middle and apical) and the contrast noise ratio (CNR) was calculated. The CNR values of images were analyzed based on the fixture material, resolution, jaw, unit parameters and fixture size by using the paired t-test and different fixture sections by one-way ANOVA. Results: Depending on the CBCT unit, the CNR values in Roxolid and Zirconium fixtures are completely different. Under higher exposure parameters, the CNR values of the Roxolid and Zirconium fixtures were significantly higher in the maxilla than mandible. However, the fixture size and longitudinal section type did not have a significant effect on the CNR values. Conclusion: In contrast to the fixture material, scanning parameters and jaw type, differences in the size and longitudinal section of the fixtures had no impact on artifact severity.

Cone-beam computed tomography-guided three-dimensional evaluation of treatment effectiveness of the Frog appliance

Objective

To evaluate the effectiveness of the Frog appliance in three dimensions by using cone-beam computed tomography (CBCT) images.

Methods

Forty patients (21 boys and 19 girls), averaged 11.7 years old, with an Angle Class II division 1 malocclusion were included in our study. They had either late mixed dentition or early permanent dentition, and the maxillary second molars had not yet erupted. All patients underwent CBCT before and after the treatment for measuring changes in the maxillary first molars, second premolars, central incisors, and profile. Paired-samples t-test was used to compare the mean difference in each variable before treatment and after the first phase of treatment.

Results

The maxillary first molars were effectively distalized by 4.25 mm (p < 0.001) and 3.53 mm (p < 0.05) in the dental crown and root apex, respectively. The tipping increased by 2.25°, but the difference was not significant. Moreover the teeth moved buccally by 0.84 mm (p < 0.05) and 2.87 mm (p < 0.01) in the mesiobuccal and distobuccal cusps, respectively, whereas no significant changes occurred in the root apex. Regarding the anchorage parts, the angle of the maxillary central incisor's long axis to the sella-nasion plane increased by 2.76° (p < 0.05) and the distance from the upper lip to the esthetic plane decreased by 0.52 mm (p = 0.01).

Conclusions

The Frog appliance effectively distalized the maxillary molars with an acceptable degree of tipping, distobuccal rotation, and buccal crown torque, with only slight anchorage loss. Furthermore, CBCT image demonstrated that it is a simple and reliable method for three-dimensional analysis.