Evaluation of high-resolution cone beam computed tomography in the detection of simulated interradicular bone lesions

Radiographic diagnosis of periodontal diseases - Current evidence versus innovations

Accurate diagnosis of periodontal and peri-implant diseases relies significantly on radiographic examination, especially for assessing alveolar bone levels, bone defect morphology, and bone quality. This narrative review aimed to comprehensively outline the current state-of-the-art in radiographic diagnosis of alveolar bone diseases, covering both two-dimensional (2D) and three-dimensional (3D) modalities. Additionally, this review explores recent technological advances in periodontal imaging diagnosis, focusing on their potential integration into clinical practice. Clinical probing and intraoral radiography, while crucial, encounter limitations in effectively assessing complex periodontal bone defects. Recognizing these challenges, 3D imaging modalities, such as cone beam computed tomography (CBCT), have been explored for a more comprehensive understanding of periodontal structures. The significance of the radiographic assessment approach is evidenced by its ability to offer an objective and standardized means of evaluating hard tissues, reducing variability associated with manual clinical measurements and contributing to a more precise diagnosis of periodontal health. However, clinicians should be aware of challenges related to CBCT imaging assessment, including beam-hardening artifacts generated by the high-density materials present in the field of view, which might affect image quality. Integration of digital technologies, such as artificial intelligence-based tools in intraoral radiography software, the enhances the diagnostic process. The overarching recommendation is a judicious combination of CBCT and digital intraoral radiography for enhanced periodontal bone assessment. Therefore, it is crucial for clinicians to weigh the benefits against the risks associated with higher radiation exposure on a case-by-case basis, prioritizing patient safety and treatment outcomes.

The Role of Radiographic Imaging in the Diagnosis and Management of Periodontal and Peri-Implant Diseases

This article highlights the role of dental imaging techniques, including periapical, bitewing, panoramic, and cone-beam computed tomography images, in the diagnostic and therapeutic decision-making process for patients with periodontal and peri-implant disease. A brief overview of common radiographic findings of periodontal disease, including periodontitis, and peri-implantitis is also provided.

Is the efficacy of cone beam computed tomography in the diagnosis of tooth ankylosis influenced by dose reduction protocols?

OBJECTIVE

To evaluate the diagnostic efficacy of cone beam computed tomography (CBCT) examinations acquired with varying dose protocols in the diagnosis of simulated tooth ankylosis (TA).

STUDY DESIGN

Tooth ankylosis was simulated in 15 of 30 teeth, and CBCT examinations were acquired at 3 mA levels (8, 6.3, and 5) and 3 voxel sizes (0.08, 0.125, and 0.2 mm). Four radiologists independently assessed the presence of TA using a 5-point scale. Sensitivity, specificity, and area under the curve (AUC) obtained through receiver operating characteristic analysis were compared among mA levels and voxel sizes using two-way analysis of variance (α = 0.05). Intra- and interexaminer reliability levels were assessed with the weighted kappa examination.

RESULTS

Sensitivity was low (0.32-0.49), and specificity was reasonably high (0.71-0.83). Mean values of AUC were low, ranging between 0.54 and 0.67, which reveals poor overall discrimination between health and disease. The detection of TA was not significantly influenced by mA level or voxel size (P > .05). Intra- and interexaminer agreements ranged from slight to moderate (0.160-0.535) and from fair to substantial (0.236-0.697), respectively.

CONCLUSIONS

Despite the limited efficacy of CBCT for TA detection, when indicated as a complementary examination, mA reduction should be considered for dose optimization purposes.

Cone-Beam Computed Tomography in Periodontal Diagnosis and Treatment Planning

Diagnosis of periodontal disease depends on conventional clinical parameters. In periodontitis with extensive bone defects, radiographs play a crucial role in arriving at a proper diagnosis. The emergence of cone-beam computed tomography (CBCT) became a boon in oral radiology. Limitations of conventional two-dimensional (2D) radiographs include inadequate visualization of bone defects, lamina dura, and furcation involvement. CBCT generates 3D images of anatomical structures necessary for the periodontal diagnosis of furcation involvement, intrabony defects, and implant placement. CBCT, thus, imparts various potential applications in the field of periodontics which serves to arrive at better diagnostic conclusions.

Evaluation of a metal artifact reduction algorithm and an adaptive image noise optimization filter in the estimation of peri-implant fenestration defects using cone beam computed tomography: an in-vitro study

OBJECTIVE

The aim of this study is to assess the effects of metal artifact reduction (MAR) and adaptive image noise enhancer (AINO) in CBCT imaging on the detection accuracy of artificially created fenestration defects in proximity to titanium and zirconium implants in sheep jaw.

METHODS

Six zirconium and 10 titanium implants were planted on mandibular jaws of three sheep, and artificial defects were created. All images were obtained with a standard voxel size (0.150 mm³) and with 4 scan modes: (1) without MAR/without AINO; (2) with MAR/without AINO; (3) without MAR/with AINO; and (4) with MAR/with AINO during CBCT scanning. A total of 60 CBCT scans were produced.

RESULTS

For all types of implants, intra- and inter-observer kappa values were the highest for MAR filter. The scan mode of with MAR filter was found to have the highest area under the curve (AUC), whereas the scan mode of without both MAR and AINO filters was found to have the lowest AUC values with statistical significance (p ≤ 0.05). Titanium implants were found to have higher AUC values than zirconium (p ≤ 0.05).

CONCLUSION

Both MAR module and AINO filters enhance the accuracy of the detection of peri-implant fenestrations; however, the use of MAR filter solely can be recommended for detection of peri-implant fenestrations.

Measuring peri-implant bone lesions using low-dose cone-beam computed tomography

PURPOSE

High-definition cone-beam computed tomography (HD-CBCT) offers superior image quality at the cost of higher radiation dose compared to low-dose CBCT (LD-CBCT). The aim of this study was to investigate whether peri-implant bone lesions can be accurately quantified using LD-CBCT, even when including the influence of surrounding tissues.

METHODS

Twelve titanium implants restored with all-ceramic crowns were placed in bovine bone, and peri-implant lesions were prepared. Radiographic imaging was performed using IR (intraoral radiography), HD-CBCT and LD-CBCT. To simulate the in-vivo situation, the samples were placed inside a dry human mandible, and a second LD-CBCT imaging was performed (LD-CBCT*). The datasets were presented to four observers in random order. Maximum lesion depth and width were measured in a standardized mesiodistal slice in IR, HD-CBCT, LD-CBCT, and LD-CBCT*. Mean lesion depth and width measurements for each sample in HD-CBCT served as reference.

RESULTS

Interrater agreement was slight for depth and excellent for width in HD-CBCT and both LD modes. For all observers, measurement deviations from HD-CBCT were below 0.3 mm in the LD protocols (LD-CBCT depth: 0.22 ± 0.17 mm, width: 0.22 ± 0.13 mm; LD-CBCT* depth: 0.24 ± 0.23 mm, width: 0.25 ± 0.21 mm) and at 0.4 mm in IR.

CONCLUSIONS

Absolute differences between LD-CBCT and HD-CBCT are small, although surrounding tissues decrease LD-CBCT image quality. Within the limitations of an in-vitro trial, LD-CBCT may become an adequate imaging modality for monitoring peri-implant lesions at a substantially decreased radiation dose.

The Chairside Periodontal Diagnostic Toolkit: Past, Present, and Future

Periodontal diseases comprise a group of globally prevalent, chronic oral inflammatory conditions caused by microbial dysbiosis and the host immune response. These diseases specifically affect the tooth-supporting tissues (i.e., the periodontium) but are also known to contribute to systemic inflammation. If left untreated, periodontal diseases can ultimately progress to tooth loss, lead to compromised oral function, and negatively impact the overall quality of life. Therefore, it is important for the clinician to accurately diagnose these diseases both early and accurately chairside. Currently, the staging and grading of periodontal diseases are based on recording medical and dental histories, thorough oral examination, and multiple clinical and radiographic analyses of the periodontium. There have been numerous attempts to improve, automate, and digitize the collection of this information with varied success. Recent studies focused on the subgingival microbiome and the host immune response suggest there is an untapped potential for non-invasive oral sampling to assist clinicians in the chairside diagnosis and, potentially, prognosis. Here, we review the available toolkit available for diagnosing periodontal diseases, discuss commercially available options, and highlight the need for collaborative research initiatives and state-of-the-art technology development across disciplines to overcome the challenges of rapid periodontal disease diagnosis.

Diagnostic accuracy of CBCT versus intraoral imaging for assessment of peri-implant bone defects

Background

Early detection of marginal bone loss is vital for treatment planning and prognosis of teeth and implant. This study was conducted to assess diagnostic accuracy of CBCT compared to intra-oral (IO) radiography for detection, classification, and measurement of peri-implant bone defects in an animal model.

Methods

Fifty-four mandible blocks with implants were harvested from nine male health adult beagle dogs with acquisition of IO, CBCT and micro-CT images from all samples. Peri-implant bone defects from 16 samples were diagnosed using micro-CT and classified into 3 defect categories: dehiscence (n = 5), infrabony defect (n = 3) and crater-like defect (n = 8). Following training and calibration of the observers, they asked to detect location (mesial, distal, buccal, lingual) and shape of the defect (dehiscence, horizontal defect, vertical defect, carter-like defect) utilizing both IO and CBCT images. Both observers assessed defect depth and width on IO, CBCT and micro-CT images at each side of peri-implant bone defect via CT-analyzer software. Data were analyzed using SPSS software and a p value of < 0.05 was considered as statistically significant.

Results

Overall, there was a high diagnostic accuracy for detection of bone defects with CBCT images (sensitivity: 100%/100%), while IO images showed a reduction in accuracy (sensitivity: 69%/63%). Similarly, diagnostic accuracy for defect classification was significantly higher for CBCT, whereas IO images were unable to correctly identify vestibular dehiscence, with incorrect assessment of half of the infrabony defects. For accuracy of measuring defect depth and width, a higher correlation was observed between CBCT and gold standard micro-CT (r = 0.91, 95% CI 0.86–0.94), whereas a lower correlation was seen for IO images (r = 0.82, 95% CI 0.67–0.91).

Conclusions

The diagnostic accuracy and reliability of CBCT was found to be superior to IO imaging for the detection, classification, and measurement of peri-implant bone defects. The application of CBCT adds substantial information related to the peri-implant bone defect diagnosis and decision-making which cannot be achieved with conventional IO imaging.

Comparison of the different voxel sizes in the estimation of peri-implant fenestration defects using cone beam computed tomography: an ex vivo study

Background

To examine the influence of voxel sizes to detect of peri-implant fenestration defects on cone beam computed tomography (CBCT) images.

Materials and methods

This study performed with three sheep heads both maxilla and mandible and two types of dental implant type 1 zirconium implant (Zr⁴⁰) (n = 6) and type 2 titanium implant (Ti²²) (n = 10). A total of 14 peri-implant fenestrations (8 buccal surfaces, 6 palatal/lingual surface) were created while 18 surfaces (8 buccal, 10 palatal/lingual) were free of fenestrations. Three observers have evaluated the images of fenestration at each site. Images obtained with 0.75 mm³, 0.100 mm³, 0.150 mm³, 0.200 mm³, and 0.400 mm³ voxel sizes. For intra- and inter-observer agreements for each voxel size, Kappa coefficients were calculated.

Results

Intra- and inter-observer kappa values were the highest for 0.150 mm³, and the lowest in 0.75 mm³ and 0.400 mm³ voxel sizes for all types of implants. The highest area under the curve (AUC) values were found higher for the scan mode of 0.150 mm³, whereas lower AUC values were found for the voxel size for 0.400 mm³. Titanium implants had higher AUC values than zirconium with the statistical significance for all voxel sizes (p ≤ 0.05).

Conclusion

A voxel size of 0.150 mm³ can be used to detect peri-implant fenestration bone defects. CBCT is the most reliable diagnostic tool for peri-implant fenestration bone defects.

Cone beam computed tomography (CBCT) in periodontal diseases: a Systematic review based on the efficacy model

Background

Periodontal diseases are prevalent among adult populations. Its diagnosis depends mainly on clinical findings supported by radiographic examinations. In previous decades, cone beam computed tomography has been introduced to the dental field. The aim of this study was to address the diagnostic efficacy of cone-beam computed tomographic (CBCT) imaging in periodontics based on a systematic search and analysis of the literature using the hierarchical efficacy model.

Methods

A systematic search of electronic databases such as PubMed, Scopus, Web of Science, and Cochrane was conducted in February 2019 to identify studies addressing the efficacy of CBCT imaging in Periodontics. The identified studies were subjected to pre-identified inclusion criteria followed by an analysis using a hierarchical model of efficacy (model) designed for an appraisal of the literature on diagnostic imaging modality. Four examiners performed the eligibility and quality assessment of relevant studies and consensus was reached in cases where disagreement occurred.

Results

The search resulted in 64 studies. Of these, 34 publications were allocated to the relevant level of efficacy and quality assessments wherever applicable. The overall diagnostic accuracy of the included studies showed a low or moderate risk of bias and applicability concerns in the use of CBCT. In addition, CBCT is accurate in identifying periodontal defects when compared to other modalities. The studies on the level of patient outcomes agreed that CBCT is a reliable tool for the assessment of outcomes after the treatment of periodontal defects.

Conclusion

CBCT was found to be beneficial and accurate in cases of infra-bony defects and furcation involvements.

Evaluation of a metal artifact reduction algorithm and an optimization filter in the estimation of peri-implant dehiscence defects by using cone beam computed tomography: an in-vitro study

OBJECTIVES

The aim of this study was to assess the effect of a metal artifact reduction (MAR) algorithm and the adaptive image noise optimizer (AINO) optimization filter in the detection of peri-implant dehiscences with cone beam computed tomography (CBCT).

STUDY DESIGN

Nine implants (3 zirconium, 3 titanium, and 3 zirconium-titanium) were placed in 3 sheep heads. Dehiscences were created on the buccal and lingual/palatal surfaces. A total of 9 defects and 9 controls with no defects were evaluated by 3 observers. Each sheep head was scanned 5 times with 4 scan modes; (1) without MAR/without AINO; (2) with MAR/without AINO; (3) without MAR/with AINO; and (4) with MAR/with AINO. Receiver operating characteristic analysis and weighted kappa coefficients were used to calculate diagnostic efficacy and intra- and interobserver agreements for each implant type and scan mode.

RESULTS

For all implant types, dehiscences were most accurately detected when both MAR and AINO were applied (P ≤ .045). Detection of dehiscences was more accurate with titanium implants (P ≤ .040). There were no significant differences in agreement among and between the observers.

CONCLUSIONS

The use of both MAR and AINO enhanced the detection accuracy of artificially created dehiscences in proximity to implants. Their combined use is recommended for detecting peri-implant dehiscences.

Measurement of the bone height of mandibular incisors and canines on computed tomography-Limitations according to bone thickness

AIM

To verify the correlation between cone beam CT (CBCT) and spiral CT (SCT) images and direct measurement of the bone height and to verify whether bone thickness (BT) influences the accuracy of bone height measurement on CT.

SETTING AND SAMPLE

One hundred and fourteen measurements were obtained in 10 dry human mandibles.

MATERIALS AND METHODS

The alveolar bone height was measured on volumetric and linear images.

RESULTS

Negative, average and significant correlations (-0.622** to -0.489**) were verified between BT and the absolute error. When the alveolar bone thickness was at least 0.6 mm, the mean differences were 0.16 and 0.28 mm on linear images and 0.12 and 0.03 mm on volumetric images for CBCT and SCT. Additionally, these values ranged from -0.46 to 0.79 and -0.32 to 0.88 mm on linear images and from -0.64 to 0.67 and -0.57 to 0.62 mm on volumetric images for CBCT and SCT. When the alveolar bone thickness was less than 0.6 mm, the CT evaluation varied from -1.74 to 5.42 and -1.64 to 5.42 mm on linear images and from -3.70 to 4.28 mm and -3.49 to 4.25 mm on volumetric images for CBCT and SCT.

CONCLUSIONS

Spiral CT and CBCT images demonstrate significant correlation with direct measurement for the alveolar bone height. Measurement of the alveolar bone labial and lingual to the mandibular incisors and canines presented higher accuracy when its thickness was greater than 0.6 mm. When the thickness was less than 0.6 mm, bone dehiscence can be diagnosed despite bone being clinically present.

Ex vivo comparison of CBCT and digital periapical radiographs for the quantitative assessment of periodontal defects

OBJECTIVES

Accurate imaging is essential for effective treatment planning in periodontology. The aim of this ex vivo study was to investigate the accuracy of cone beam computed tomography (CBCT) and digital periapical radiographs (PA) in imaging periodontal defects. Hypotheses are: 1. That CBCT is a more accurate method than PA concerning vertical measurements of periodontal bone defects2. That CBCT itself is an accurate method to describe vertical periodontal bone loss MATERIAL AND METHODS: In this study, 117 periodontal defects from 10 human cadavers were investigated radiographically by CBCT and PA by one calibrated observer. Afterwards the vertical bone loss was measured with a periodontal probe by the same calibrated observer. Differences between radiographic and clinical measurements were calculated and analyzed. Bland-Altmann plots including 95% limits of agreement were calculated.

RESULTS

The 95% limits of agreement ranged from 3.29 to -3.27 mm between clinical measurements and measurements in PAs, and from 2.13 to -1.97 mm in CBCTs. The mean difference between clinical and radiographic measurements was 0.0009 mm for PA and 0.0835 mm for CBCT.

CONCLUSIONS

When comparing the clinical measurements, CBCT had a higher agreement and less deviations than PAs, and CBCT seems to be an accurate method to describe vertical periodontal bone loss.

CLINICAL RELEVANCE

Accurate description of defects is helpful for accurate treatment planning.

Comparison of conventional imaging techniques and CBCT for periodontal evaluation: A systematic review

Purpose

This study aimed to carry out a systematic review of studies in the literature comparing conventional imaging techniques with cone-beam computed tomography in terms of the role of these techniques for assessing any of the following periodontal conditions and parameters: infrabony defects, furcation involvement, height of the alveolar bone crest, and the periodontal ligament space.

Materials and Methods

Interventional and observational studies comparing conventional imaging techniques with cone-beam computed tomography were considered eligible for inclusion. The MEDLINE and Embase databases were searched for articles published through 2017. The PRISMA statement was followed during data assessment and extraction.

Results

The search strategy yielded 351 publications. An initial screening of the publications was performed using abstracts and key words, and after the application of exclusion criteria, 13 studies were finally identified as eligible for review.

Conclusion

These studies revealed cone-beam computed tomography to be the best imaging technique to assess infrabony defects, furcation lesions, the height of the alveolar bone crest, and the periodontal ligament space.

Comparison of the burr and chemically induced periodontal defects using different field-of-view sizes and voxel resolutions

OBJECTIVE

This study assessed the use of different voxel resolutions in a cone beam computed tomography (CBCT) unit for the detection of artificially induced periodontal bone defects created using burr, burr and chemicals, and only chemicals.

STUDY DESIGN

Seven dry skulls were used in this study. In total, 65 dehiscence defects, 43 fenestration defects, and 76 control sites with no periodontal defects were examined. Images were obtained from a CBCT unit (3 D Accuitomo; J Morita Mfg. Corp., Kyoto, Japan), using 3 field-of-view (FOV) sizes (4 × 4 cm; 6 × 6 cm; and 8 × 8 cm) and 4 scan modes (standard, high-definition, high-fidelity, and low-dose).

RESULTS

Overall, κ coefficients for interobserver agreement on burr-induced periodontal defects ranged from 0.336 to 0.795, with the lowest κ value (indicating a fair degree of agreement) obtained for images acquired in standard mode with a voxel size of 0.160 mm³. κ coefficients for the detection of periodontal defects were highest (indicating moderate to high degrees of interobserver agreement) for smaller voxel sizes and high-resolution images. Statistical comparison among groups (burr, burr + chemicals, and chemicals only) was performed using 1-way analysis of variance with post hoc tests.

CONCLUSIONS

The CBCT scan mode may affect the diagnosis of periodontal defects. The technique used to create periodontal defects also affected diagnosis. For this kind of experiment, burr-induced or burr + chemical-induced defects should be used, rather than those induced solely using a chemical technique.

Precision of cone beam CT to assess periodontal bone defects: a systematic review and meta-analysis

OBJECTIVES

Evaluate the diagnostic validity of CBCT in measuring periodontal bone defects when compared with the reference standard (in situ measurement).

METHODS

Studies in which the main objective was to evaluate the diagnostic validity of CBCT in measuring periodontal bone defects when compared with the reference standard were selected. Four databases were searched. The studies were selected by two independent reviewers. The methodology of selected studies was assessed using the 14-item Quality Assessment Tool for Diagnostic Accuracy Studies. The quality of evidence and strength of recommendation was assessed by The Grading of Recommendations Assessment Tool, Development and Evaluation.

RESULTS

Using a selection process in two phases, 16 studies were identified and, in seven articles meta-analysis was performed. The results from these meta-analyses showed that no difference between the measurements of CBCT and in situ for alveolar bone loss, and demonstrated a concordance of 82.82% between CBCT and in situ for the classification of the degree of furcation involvement.

CONCLUSIONS

Based on a moderate level of evidence, CBCT could be useful for furcation involvement periodontal cases, but it should only be used in cases where clinical evaluation and conventional radiographic imaging do not provide the information necessary for an adequate diagnosis and proper periodontal treatment planning.

Performance of cone beam computed tomography and conventional intraoral radiographs in detecting interproximal alveolar bone lesions: a study in pig mandibles

Background

Cone beam computed tomography (CBCT) has been largely used in dentistry. Nevertheless, there is lack of evidence regarding CBCT accuracy in the diagnosis of early periodontal lesions as well as the correlation between accuracy and lesion size. The aim of this study was to evaluate accuracy of CBCT and conventional intraoral radiographs in detecting different-sized interproximal bone lesions created in pig mandibles. The hypothesis was that CBCT accuracy would be superior to radiographs in detecting incipient bone lesions.

Methods

Twenty swine dry mandibles were used, totalizing 80 experimental sites. Four groups were created according to exposure time to perchloric acid 70–72%: controls (no exposure), 2-hour exposure, 4-hour exposure, and 6-hour exposure. Standardized CBCT and conventional intraoral radiographs were taken and analyzed by two trained radiologists. The presence of lesions in the dry mandible was considered the gold standard. Sensitivity, specificity, and accuracy in detecting different-sized bone lesions were calculated for CBCT and intraoral radiographs.

Results

Accuracy of CBCT ranged from 0.762 to 0.825 and accuracy of periapical radiography ranged from 0.700 to 0.813, according to examiner and time of acid exposure. Inter-examiner agreement varied from slight to fair, whereas intra-examiner agreement varied from moderate to substantial.

Conclusions

CBCT performance was not superior to that provided by conventional intraoral radiographs in the detection of interproximal bone loss.

Dose optimization for assessment of periodontal structures in cone beam CT examinations

OBJECTIVES

To investigate the relationship between dose and image quality for a dedicated dental CBCT scanner using different scanning protocols and to set up an optimal imaging protocol for assessment of periodontal structures.

METHODS

Radiation dose and image quality measurements were made using 3D Accuitomo 170 (J. Morita, Kyoto, Japan) dental CBCT scanner. The SedentexCT IQ phantom was used to investigate the relationship between contrast-to-noise ratio (CNR) and dose-area product. Subjective image quality assessment was achieved using a small adult skull phantom for the same range of exposure settings. Five independent observers assessed the images for three anatomical landmarks using a three-point visual grade analysis.

RESULTS

When correlating the CNR of each scanning protocol to the exposure parameters used to obtain it, CNR decreased as these parameters decreased, especially current-exposure time product. When correlating to subjective image quality, the CNR level remained acceptable when 5 mA and 17.5 s or greater was selected and 80 kV could be used without compromising the CNR.

CONCLUSIONS

For a dedicated CBCT unit, changing the rotation angle from 360° to 180° degrades image quality. By altering tube potential and current for the 360° rotation protocol, assessment of periodontal structures can be performed with a smaller dose without substantially affecting visualization.

Effects of exposure parameters and slice thickness on detecting clear and unclear mandibular canals using cone beam CT

OBJECTIVES

The purpose of this study was to clarify the effects of exposure parameters and image-processing methods when using CBCT to detect clear and unclear mandibular canals (MCs).

METHODS

24 dry half mandibles were divided into 2 groups with clear and unclear MCs based on a previous CBCT study. Mandibles were scanned using a CBCT system with varying exposure parameters (tube voltages 60 kV, 70 kV and 90 kV; and tube currents 2 mA, 5 mA, 10 mA and 15 mA) to obtain a total of 144 scans. The images were processed with different slice thicknesses using ImageJ software (National Institutes of Health, Bethesda, MD). Five radiologists evaluated the cross-sectional images of the first molar region to detect the MCs. The diagnostic accuracy of varying exposure parameters and image-processing conditions was compared with the area under the curve (Az) in receiver-operating characteristic analysis.

RESULTS

The Az values for clear MCs were higher than those for unclear MCs (p < 0.0001). With increasing exposure voltages and currents, Az values increased, but no significant differences were found with high voltages and currents in clear MCs (p = 1.0000 and p = 0.9340). The Az values of serial images were higher than those of overlaid images (p < 0.0001), and those for thicker slices were higher than those for thinner slices (p < 0.0001).

CONCLUSIONS

Our findings indicate that detection of unclear MCs requires either higher exposure parameters or processing of the images with thicker slices. To detect clear MCs, lower exposure parameters can be used.

Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient's life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar.

Detection of simulated periodontal defects using cone-beam CT and digital intraoral radiography

OBJECTIVES:

This study sought to assess the diagnostic value of CBCT and digital intraoral radiography for the detection of periodontal defects in the sheep mandible.

METHODS:

In this in vitro study, 80 periodontal defects including Grades I, II and III furcation involvements, one-, two-, three-wall and trough-like infrabony defects, fenestration and dehiscence were artificially created in the sheep mandible by burr. Intraoral digital radiographs using photostimulable phosphor plates and CBCT scans were obtained. Three periodontists evaluated the images for the presence and type of defects. The results were compared with the gold standard (photographs of the created defects).

RESULTS:

CBCT scans were significantly superior to digital radiographs for the detection of Grade I furcation involvements, three-wall defects, fenestrations and dehiscence (p < 0.05). No significant difference was noted between CBCT and digital radiography for the detection of Grades II and III furcation involvements, one-wall, two-wall and trough-like defects (p-value > 0.05).

CONCLUSIONS:

CBCT was superior to digital intraoral radiography for the detection of Grade I furcation involvements, three-wall defects, dehiscence and fenestrations.

Accuracy and precision of cone beam computed tomography in periodontal defects measurement (systematic review)

Systematic review of literature was made to assess the extent of accuracy of cone beam computed tomography (CBCT) as a tool for measurement of alveolar bone loss in periodontal defect. A systematic search of PubMed electronic database and a hand search of open access journals (from 2000 to 2015) yielded abstracts that were potentially relevant. The original articles were then retrieved and their references were hand searched for possible missing articles. Only articles that met the selection criteria were included and criticized. The initial screening revealed 47 potentially relevant articles, of which only 14 have met the selection criteria; their CBCT average measurements error ranged from 0.19 mm to 1.27 mm; however, no valid meta-analysis could be made due to the high heterogeneity between the included studies. Under the limitation of the number and strength of the available studies, we concluded that CBCT provides an assessment of alveolar bone loss in periodontal defect with a minimum reported mean measurements error of 0.19 ± 0.11 mm and a maximum reported mean measurements error of 1.27 ± 1.43 mm, and there is no agreement between the studies regarding the direction of the deviation whether over or underestimation. However, we should emphasize that the evidence to this data is not strong.

Cone-Beam Computed Tomography for Detection of Intrabony and Furcation Defects: A Systematic Review Based on a Hierarchical Model for Diagnostic Efficacy

BACKGROUND

The aim of this review is to assess the diagnostic efficacy of cone-beam computed tomography (CBCT) for the diagnosis of and/or treatment planning for intrabony and furcation defects, using a well-known six-tiered hierarchical model for diagnostic efficacy.

METHODS

The MEDLINE, EMBASE, and Cochrane Library bibliographic databases were searched until August 2015 for studies evaluating CBCT imaging for the diagnosis of and/or treatment planning for intrabony and/or furcation defects. The search strategy was restricted to English language publications using the combination of MeSH terms, free terms, and key words.

RESULTS

The search strategy yielded 16 publications that qualitatively or quantitatively evaluated the use of CBCT for the detection of intrabony and/or furcation defects and how CBCT influenced the diagnosis and/or treatment plan. According to Quality Assessment of Studies of Diagnostic Accuracy-2, all included studies were medium to low risk of bias. The review identified only one study that investigated the societal efficacy, and none evaluated the patient outcome efficacy or therapeutic efficacy. One study investigated the diagnostic thinking efficacy. All other included studies investigated the diagnostic accuracy of CBCT.

CONCLUSIONS

From the assessed studies, it can be concluded that there is not sufficient scientific evidence to justify the use of CBCT for the diagnosis of and/or treatment planning for intrabony and furcation defects. Furthermore, the effectiveness of CBCT for such diagnostic tasks has been assessed only at low diagnostic efficacy levels.

Accuracy of digital periapical radiography and cone-beam computed tomography in detecting external root resorption

PURPOSE

The purpose of this study was to evaluate and compare the efficacy of cone-beam computed tomography (CBCT) and digital intraoral radiography in diagnosing simulated small external root resorption cavities.

MATERIALS AND METHODS

Cavities were drilled in 159 roots using a small spherical bur at different root levels and on all surfaces. The teeth were imaged both with intraoral digital radiography using image plates and with CBCT. Two sets of intraoral images were acquired per tooth: orthogonal (PA) which was the conventional periapical radiograph and mesioangulated (SET). Four readers were asked to rate their confidence level in detecting and locating the lesions. Receiver operating characteristic (ROC) analysis was performed to assess the accuracy of each modality in detecting the presence of lesions, the affected surface, and the affected level. Analysis of variation was used to compare the results and kappa analysis was used to evaluate interobserver agreement.

RESULTS

A significant difference in the area under the ROC curves was found among the three modalities (P=0.0002), with CBCT (0.81) having a significantly higher value than PA (0.71) or SET (0.71). PA was slightly more accurate than SET, but the difference was not statistically significant. CBCT was also superior in locating the affected surface and level.

CONCLUSION

CBCT has already proven its superiority in detecting multiple dental conditions, and this study shows it to likewise be superior in detecting and locating incipient external root resorption.

Evaluation of accuracy of cone beam computed tomography for measurement of periodontal defects: A clinical study

Aims:

The aim of the present study was to evaluate the accuracy of Cone Beam Computed Tomography (CBCT) measurements of alveolar bone defects caused due to periodontal disease, by comparing it with actual surgical measurements which is the gold standard.

Materials and Methods:

Hundred periodontal bone defects in fifteen patients suffering from periodontitis and scheduled for flap surgery were included in the study. On the day of surgery prior to anesthesia, CBCT of the quadrant to be operated was taken. After reflection of the flap, clinical measurements of periodontal defect were made using a reamer and digital vernier caliper. The measurements taken during surgery were then compared to the measurements done with CBCT and subjected to statistical analysis using the Pearson's correlation test.

Results:

Overall there was a very high correlation of 0.988 between the surgical and CBCT measurements. In case of type of defects the correlation was higher in horizontal defects as compared to vertical defects.

Conclusions:

CBCT is highly accurate in measurement of periodontal defects and proves to be a very useful tool in periodontal diagnosis and treatment assessment.

Comparison of the influence of FOV sizes and different voxel resolutions for the assessment of periodontal defects

OBJECTIVES

This study assessed the influence of different voxel resolutions of two different CBCT units on the in vitro detection of periodontal defects.

METHODS

The study used 12 dry skulls with a maxilla and a mandible. Artificial defects (dehiscence, tunnel, fenestration) were separately created on the anterior, premolar and molar teeth using burrs. A total of 14 dehiscences, 13 fenestrations, 8 tunnels and 16 non-defect controls were used in the study. Images were obtained from two different CBCT units in six voxel sizes (voxel size: 0.080, 0.100, 0.125, 0.150, 0.160 and 0.200 mm3). Kappa coefficients were calculated to assess both intra- and interobserver agreements for each image set.

RESULTS

Overall intraobserver kappa coefficients ranged between 0.978 and 0.973 for the 0.080-mm3 images and between 0.751 and 0.737 for the 0.160-mm3 images, suggesting notably high intraobserver agreement for detecting periodontal defects. CBCT performed significantly better at detecting fenestrations (p<0.05) than tunnel and dehiscence defects. No statistically significant difference was found between the detection of dehiscence and tunnel defects (p>0.05).

CONCLUSIONS

A voxel size of 0.150 mm3 was identified as the cut-off point for overall detection of periodontal defects. CBCT should be considered the most reliable imaging modality for the diagnosis of periodontal defects.

Use of cone beam computed tomography in periodontology

Diagnosis of periodontal disease mainly depends on clinical signs and symptoms. However, in the case of bone destruction, radiographs are valuable diagnostic tools as an adjunct to the clinical examination. Two dimensional periapical and panoramic radiographs are routinely used for diagnosing periodontal bone levels. In two dimensional imaging, evaluation of bone craters, lamina dura and periodontal bone level is limited by projection geometry and superpositions of adjacent anatomical structures. Those limitations of 2D radiographs can be eliminated by three-dimensional imaging techniques such as computed tomography. Cone beam computed tomography (CBCT) generates 3D volumetric images and is also commonly used in dentistry. All CBCT units provide axial, coronal and sagittal multi-planar reconstructed images without magnification. Also, panoramic images without distortion and magnification can be generated with curved planar reformation. CBCT displays 3D images that are necessary for the diagnosis of intra bony defects, furcation involvements and buccal/lingual bone destructions. CBCT applications provide obvious benefits in periodontics, however; it should be used only in correct indications considering the necessity and the potential hazards of the examination.

Diagnostic Applications of Cone-Beam CT for Periodontal Diseases

Objectives. This paper aims to review the diagnostic application of cone beam computed tomography (CBCT) in the field of periodontology. Data. Original articles that reported on the use of CBCT for periodontal disease diagnosis were included. Sources. MEDLINE (1990 to January 2014), PubMed (using medical subject headings), and Google Scholar were searched using the following terms in different combinations: “CBCT,” “volumetric CT,” “periodontal disease ,” and “periodontitis.” This was supplemented by hand-searching in peer-reviewed journals and cross-referenced with the articles accessed. Conclusions. Bony defects, caters, and furcation involvements seem to be better depicted on CBCT, whereas bone quality and periodontal ligament space scored better on conventional intraoral radiography. CBCT does not offer a significant advantage over conventional radiography for assessing the periodontal bone levels.

Diagnostic accuracy of CBCT for periodontal lesions

OBJECTIVES

The present study compares the diagnostic value of periodontal bone defect images using conventional two-dimensional single-tooth radiographs and three-dimensional cone beam computed tomography (CBCT) images.

MATERIALS AND METHODS

Classified periodontal bone defects were prepared on pig mandibles and presented radiographically. Fifteen dentists were instructed to make a diagnosis based on these x-rays, regarding the type and the extent of the bone defects. Subsequently, the results were evaluated and compared to the morphology of the surgically prepared defects as the gold standard.

RESULTS

On average, the diagnosis of infrabony defects were 21 %, dehiscence 25 %, and fenestration 33 % more accurate using the three-dimensional projection than with the single-tooth radiograph. Furthermore, the CBCT allows grade II furcation to be captured more accurately.

CONCLUSIONS

The results of this study indicate that a considerably more precise analysis of periodontal defects is possible due to the third dimension. Particularly, in the oro-vestibular orientation, defects could be detected significantly more accurate.

CLINICAL RELEVANCE

CBCT images offer an advantageous alternative to the conventional single-tooth radiograph while taking the higher exposure of radiation into account.

Cone-beam computed tomography: time for an evidence-based approach

Cone-beam computed tomography (CBCT) is an imaging technology that has revolutionised dental imaging in the last decade. Although of particular value to specialists performing implant treatment, it is increasingly being adopted by general dental practitioners. As the radiation dose is higher than that of conventional radiography, it is important to consider its diagnostic efficacy for the common tasks performed in general dental practice, such as caries diagnosis, endodontics and the detection of periapical pathosis. Any new imaging technique needs to have proven advantages over existing techniques before it is adopted, yet the evidence remains quite limited. Furthermore, image quality and radiation doses vary enormously between different manufacturers' equipment, so that extrapolating results of one piece of research from one CBCT machine to another is fraught with pitfalls. Radiation doses with CBCT are typically an order of magnitude higher than conventional radiography. There is scope, however, for reducing these doses by judicious adjustment of exposure factors and limiting the field of view to the smallest dimensions consistent with the clinical situation. There is still a long way to go before we understand the value of CBCT in dentistry. High quality research evidence is needed, particularly with regard to assessing whether using BCT improves patient outcomes.

Detection of simulated incipient furcation involvement by CBCT: an in vitro study using pig mandibles

The aim of the present study was to test the reproducibility, sensitivity, and specificity of cone-beam computed tomography (CBCT) in detecting incipient furcation involvement. Fifteen macerated pig mandibles, with intact second molar teeth and preserved adjacent cortical areas, were used. Simulated lesions were created in the furcation region of these teeth by applying 70% perchloric acid in up to four possible buccal/lingual sites in the right/left sides of each mandible. The mandibles were then submitted to a CBCT scan. Two blinded and calibrated experienced oral and maxillofacial radiologists interpreted the exams. Furcation involvement was also assessed in the regions without simulated lesions. CBCT showed high levels of accuracy, ranging from 78% to 88%. The variations in Kappa values for intra- and inter-observer agreement (0.41-0.59) were considered moderate. CBCT can be considered a reliable and accurate method for detecting incipient furcation involvement.

Effect of root canal filling materials on dimensions of cone-beam computed tomography images

Objective

To evaluate the discrepancy of root canal filling (RCF) measurements obtained from original root specimens and cone-beam computed tomography (CBCT) images.

Material and Methods

Seventy-two human maxillary anterior teeth were prepared up to an ISO #50 K-File 1 mm short of the apical foramen. Thus, the teeth were randomly divided into 8 groups, according to the root canal filling material: Sealapex^®, Sealapex^®+gutta-percha points, Sealer 26^®, Sealer 26^®+gutta-percha points, AH PlusTM, AH PlusTM+gutta-percha points, Grossman Sealer, and Grossman Sealer+gutta-percha points. After root canal preparation and RCF, CBCT scans were acquired and the specimens were sectioned in axial, sagittal and coronal planes. The RCF measurements were obtained in different planes and thicknesses to determine the discrepancy between the original root specimens (using a digital caliper) and the CBCT images (using the scanner's proprietary software). One-way analysis of variance and Tukey tests were used for statistical analyses. The significance level was set at α=5%.

Results

Measurements of the different endodontic filling materials were 9% to 100% greater on the CBCT images than on the original root specimens. Greater RCF dimensions were found when only sealers were used, with statistically significant difference among the groups.

Conclusions

RCF dimensions were greater on CBCT images than on the original root specimens, especially when only sealer was used.

Is there a role for the use of volumetric cone beam computed tomography in periodontics?

Volumetric computed cone beam tomography offers a number of significant advantages over conventional intraoral and extraoral panoramic radiography, as well as computed tomography. To date, periodontal diagnosis has relied heavily on the assessment of both intraoral radiographs and extraoral panoramic radiographs. With emerging technology in radiology there has been considerable interest in the role that volumetric cone beam computed tomography might play in periodontal diagnostics. This narrative reviews the current evidence and considers whether there is a role for volumetric cone beam computed tomography in periodontics.

Deriving Hounsfield units using grey levels in cone beam CT: a clinical application

OBJECTIVE

To present a clinical study demonstrating a method to derive Hounsfield units from grey levels in cone beam CT (CBCT).

METHODS

An acrylic intraoral reference object with aluminium, outer bone equivalent material (cortical bone), inner bone equivalent material (trabecular bone), polymethlymethacrylate and water equivalent material was used. Patients were asked if they would be willing to have an acrylic bite plate with the reference object placed in their mouth during a routine CBCT scan. There were 31 scans taken on the Asahi Alphard 3030 (Belmont Takara, Kyoto, Japan) and 30 scans taken on the Planmeca ProMax 3D (Planmeca, Helsinki, Finland) CBCT. Linear regression between the grey levels of the reference materials and their linear attenuation coefficients was performed for various photon energies. The energy with the highest regression coefficient was chosen as the effective energy. The attenuation coefficients for the five materials at the effective energy were scaled as Hounsfield units using the standard Hounsfield units equation and compared to those derived from the measured grey levels of the materials using the regression equation.

RESULTS

In general, there was a satisfactory linear relation between the grey levels and the attenuation coefficients. This made it possible to calculate Hounsfield units from the measured grey levels. Uncertainty in determining effective energies resulted in unrealistic effective energies and significant variability of calculated CT numbers. Linear regression from grey levels directly to Hounsfield units at specified energies resulted in greater consistency.

CONCLUSIONS

The clinical application of a method for deriving Hounsfield units from grey levels in CBCT was demonstrated.

Endodontic clinical management of a dens invaginatus case by using a unique treatment approach: a case report

INTRODUCTION

Dens invaginatus is a developmental anomaly that poses treatment challenges when nonsurgical root canal therapy is deemed necessary. Teeth with complex root canal morphology often require a comprehensive treatment approach to effectively clean, shape, and disinfect the pulp canal space before obturation. Endodontic clinical management of a tooth with dens invaginatus might include using cone-beam computed tomography (CBCT) to aid in the diagnosis and treatment-planning phase and use of the surgical operating microscope in performing the clinical phase of treatment. A novel approach could include using the revascularization technique as the final treatment step in the management of a dens invaginatus case in which the root apex has not completed formation.

METHODS

This case report will provide both an overview of the feasibility of using CBCT scans in diagnosis and treatment planning and a step-by-step clinical technique, by using surgical operating microscope and the revascularization technique, in the successful endodontic management of a complex dens invaginatus case.

CONCLUSIONS

Five-month and 12-month follow-up clinical and radiographic findings will provide a candid view of inherent advantages and challenges of this technique.

Variation in costs of cone beam CT examinations among healthcare systems

OBJECTIVES

To analyse the costs of cone beam CT (CBCT) in different healthcare systems for patients with different clinical conditions.

METHODS

Costs were calculated for CBCT performed in Cluj (Romania), Leuven (Belgium), Malmö (Sweden) and Vilnius (Lithuania) on patients with (i) a maxillary canine with eruption disturbance, (ii) an area with tooth loss prior to implant treatment or (iii) a lower wisdom tooth planned for removal. The costs were calculated using an approach based on the identification, measurement and valuation of all resources used in the delivery of the service that combined direct costs (capital equipment, accommodation, labour) with indirect costs (patients' and accompanying persons' time, "out of pocket" costs for examination fee and visits).

RESULTS

The estimates for direct and indirect costs varied among the healthcare systems, being highest in Malmö and lowest in Leuven. Variation in direct costs was mainly owing to different capital costs for the CBCT equipment arising from differences in purchase prices (range €148 000-227 000). Variation in indirect costs were mainly owing to examination fees (range €0-102.02).

CONCLUSIONS

Cost analysis provides an important input for economic evaluations of diagnostic methods in different healthcare systems and for planning of service delivery. Additionally, it enables decision-makers to separate variations in costs between systems into those due to external influences and those due to policy decisions. A cost evaluation of a dental radiographic method cannot be generalized from one healthcare system to another, but must take into account these specific circumstances.

Digital method for quantification of circumferential periodontal bone level using cone beam CT

OBJECTIVES

The objective of this study is to develop a new approach for radiographically measuring circumferential periodontal bone level using cone beam CT (CBCT) data. Accuracy and precision were assessed using direct probe measurements on a human skull as a reference.

MATERIALS AND METHODS

Digital quantification of circumferential periodontal bone levels was conducted considering bone level measurements, infrabony crater, and furcation detection. For this purpose, a human bony cadaver skull with a restoration free dentition was used, showing periodontal bony defects of teeth 15-17,25-27,35-37,45-47 (FDI classification). Image datasets were acquired using a Promax 3D CBCT device (Planmeca Oy, Helsinki, Finland) at 80 kV and 8 mA, 160 μm voxel size. Circumferential radiographic measurements between cemento-enamel junction and the alveolar crest for the mesial, central, and distal bone levels on the oral and vestibular sides of the examined teeth were carried out based on a prototype of specifically developed software. The measurements were performed by an expert panel of three independent, calibrated, and blinded observers. Manual probe measurements of the periodontal bone loss served as reference standard.

RESULTS

The adopted software allowed the quantification of periodontal bone loss at all examined teeth. Overall deviation between radiographic and manual measurements of the observers ranged between 0.36 and 0.69 mm; hereby, 83 % of all results were <0.5 mm. Comparing overall accuracy between the ten turns of radiological measurements, accuracy for all observers ranged from 0.29 to 0.46 mm. The present study design showed a 100 % detection of furcation involvement for radiographic evaluation.

CONCLUSIONS

The adoption of a special measurement procedure in terms of a 3D coordinate system, which is placed through and perpendicular to the long axis of the tooth, allows consistent measurement positions of the mesial, central, and distal bone levels both for the oral and vestibular sides of the alveolar crest. In this way, reliable and reproducible quantification of circumferential periodontal bone loss using CBCT data with standardized resolution of 160 μm can be performed in all three dimensions.

CLINICAL RELEVANCE

This new approach of radiographically assessing circumferential periodontal bone level using CBCT data shows a first promising attempt of accurate detection of periodontal bony defects. Yet, possible negative impact of further clinical parameters in terms of artifact occurrence will have to be furthermore carefully investigated.