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  • 1.
    Al-Okshi, Ayman
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Nilsson, M.
    Malmö högskola, Faculty of Odontology (OD).
    Petersson, A.
    Malmö högskola, Faculty of Odontology (OD).
    Wiese, M.
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Using GafChromic film to estimate the effective dose from dental cone beam CT and panoramic radiography2013In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 42, no 7, article id 20120343Article in journal (Refereed)
    Abstract [en]

    Objectives: To demonstrate the feasibility of GafChromic(®) XR-QA2 (ISP Corp., Wayne, NJ) as a dosemeter when performing measurements of the effective dose from three cone beam CT (CBCT) units and to compare the doses from examinations of three common dental clinical situations. A second aim was to compare the radiation doses for three digital panoramic units with the doses for the CBCT units. METHODS: The CBCT units used were Veraviewepocs 3De(®) (J Morita MFG Corp., Kyoto, Japan), ProMax(®) 3D (Planmeca, Helsinki, Finland) and NewTom VGi(®) (Quantitative Radiology, Verona, Italy). GafChromic XR-QA2 films were placed between the selected layers of the head and neck of a tissue-equivalent human skull (RANDO(®) phantom; The Phantom Laboratory, Salem, NY). The exposure parameters were set using the automatic exposure control function of the units. Depending on the availability, medium and smaller field of view (FOV) scanning modes were used. The effective dose was estimated using the 2007 International Commission on Radiological Protection formalism. RESULTS: The lowest effective dose of a CBCT unit was observed for ProMax 3D, FOV 4 × 5 cm (10 μSv), the highest for NewTom VGi, FOV 8 × 8 cm-high resolution (129 μSv). The range of effective doses for digital panoramic machines measured was 8-14 μSv. CONCLUSIONS: This study demonstrates the feasibility of using radiochromic films for dental CBCT and panoramic dosimetry.

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  • 2.
    Al-Okshi, Ayman
    et al.
    Malmö University, Faculty of Odontology (OD).
    Paulsson, Liselotte
    Malmö University, Faculty of Odontology (OD).
    Rohlin, Madeleine
    Malmö University, Faculty of Odontology (OD).
    Ebrahim, Eman
    Malmö University, Faculty of Odontology (OD).
    Lindh, Christina
    Malmö University, Faculty of Odontology (OD).
    Measurability and reliability of assessments of root length and marginal bone level in cone beam CT and intraoral radiography: a study of adolescents2019In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 48, no 5, p. 1-9, article id 20180368Article in journal (Refereed)
    Abstract [en]

    Objectives: To evaluate measurability and reliability of measurements of root length and marginal bone level in CBCT, periapical (PA) and bitewing (BW) radiographs. Methods: CBCT of both jaws, PA of maxillary incisors and posterior BW radiographs of 10 adolescents (mean age 13.4) were selected. The radiographs comprised part of the baseline examinations of a trial of orthodontic treatment. Six raters assessed measurability and measured root length and marginal bone level. Three raters repeated their assessments. Measurability was expressed as frequency of interpretable sites and reliability as intraclass correlation coefficient (ICC). Results: Measurability was 100 % in CBCT and 95 % in PA of maxillary incisors for root length measurements. For marginal bone level, measurability was 100 % in CBCT, 76 % in PA and 86 % in posterior BW. Mean ICC for interrater reliability for root length measurements in CBCT was 0.88 (range 0.27-0.96 among different teeth) and 0.69 in PA of maxillary incisors. For marginal bone level measurements, mean ICC was 0.4 in CBCT, 0.38 in PA of maxillary incisors and 0.4 in posterior BW. Intrarater reliability varied among methods, root length or marginal bone level and among raters, except for root length measurements in CBCT, which presented high reliability (above 0.8) for all raters. Conclusions: As measurability and reliability were high for root length measurements in CBCT, this may be the method of choice for scientific analyses in orthodontics. For clinical praxis, we recommend PA following the "as low as diagnostically acceptable" principle, as clinical decisions seem to be influenced only when severe root resorption occurs.

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  • 3.
    Al-Okshi, Ayman
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Theodorakou, Chrysoula
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Dose optimization for assessment of periodontal structures in cone beam CT examinations2016In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 46, no 3, article id 20160311Article in journal (Refereed)
    Abstract [en]

    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 degrees to 180 degrees degrades image quality. By altering tube potential and current for the 360 degrees rotation protocol, assessment of periodontal structures can be performed with a smaller dose without substantially affecting visualization.

  • 4.
    Andresen, Amanda K H
    et al.
    University of Bergen, Norway.
    Jonsson, Malin V
    University of Bergen, Norway; Oral Health Centre of Expertise in Western Norway.
    Sulo, Gerhard
    Oral Health Centre of Expertise in Western Norway; Norwegian Institute of Public Health.
    Thelen, Dorina S
    Oral Health Centre of Expertise in Western Norway.
    Shi, Xie-Qi
    Malmö University, Faculty of Odontology (OD).
    Radiographic features in 2D imaging as predictors for justified CBCT examinations of canine-induced root resorption.2021In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 51, no 1, article id 20210165Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: This retrospective observational study aimed to evaluate the diagnostic accuracy of two-dimensional radiographs on canine-induced root resorption (CIRR) in lateral incisors and identify predictors of CIRR in patients with impacted maxillary canines (IMC).

    METHODS: Ninety-nine patients aged 9-17 years, with 156 IMCs, were included in the study. All had CBCT-volumes and two-dimensional radiographs consisting of at least one panoramic radiograph. Two radiologists jointly viewed all cases twice. First, radiographic features related to the IMC and possible CIRR were recorded from two-dimensional radiographs. Then, CIRR was determined from CBCT and according to position and extension classified as mild, moderate and severe.

    RESULTS: CIRRs was detected in 80% of lateral incisors (mild: 45%; moderate: 44%; severe: 11%). The sensitivity was generally low at mild and moderate cut-offs (29 and 29%), and somewhat higher for severe (50%). Corresponding specificities were 48%, 63% and 68%. Canine cusp-tip superimposing the lateral incisor's middle third and root/crown ratio >1 was positively associated with mild CIRR, with an odds ratio (OR) of 3.8 and 6.7, respectively. In addition, the root development stage was positively associated with moderate/severe CIRR when the canine root was nearly or fully developed (OR = 3.1).

    CONCLUSIONS: The diagnostic accuracy of two-dimensional radiographs was inadequate for detecting CIRR amongst patients referred for CBCT examinations. Based on our results, none of the suggested two-dimensional radiographic features could predict moderate/severe CIRR except for root development stage. IMC in a later stage of root development seems to be associated with a higher risk of moderate/severe CIRR.

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  • 5. Aziman, Cinar
    et al.
    Hellén-Halme, Kristina
    Malmö University, Faculty of Odontology (OD).
    Shi, Xie-Qi
    A comparative study on image quality of two digital intraoral sensors.2019In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 48, no 7, p. 1-5, article id 20190063Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The aims of this study were to evaluate the subjective image quality and reliability of two digital sensors. In addition, the image quality of the two sensors evaluated by specialists and general dentists were compared. METHODS: 30 intraoral bitewings from five patients were included in the study, 15 were exposed with a Dixi sensor (CCD-based) and 15 with a ProSensor (CMOS-based) using modified parallel technique. Three radiologists and three general dentists evaluated the images in pair. A five-point scale was used to register the image quality. Visual grading characteristics (VGC) analysis was performed to compare the image quality and the observer agreement was assessed in terms of intra class correlation co-efficient. RESULTS: No statistically significant difference was found on image quality between the sensors. The average scores of the observer agreement were moderate with an average of 0.66 and an interval of 0.30 to 0.87, suggesting that there was a large variation on preference of image quality. However, there was a statistically significant difference in terms of the area under the VGC- curves between the specialist group and the general dentist group ( p = 0.043), in which the specialist group tended to favor the ProSensor. CONCLUSIONS: Subjective image quality of the two intraoral sensors were comparable when evaluated by both general and oral radiologists. However, the radiologists seemed to prefer the ProSensor to the Dixi as compared to general dentists. Inter- observer conformance showed a large variation on the preference of the image quality.

  • 6. Brown, J.
    et al.
    Jacobs, R.
    Levring Jäghagen, E.
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Baksi, G.
    Schulze, D.
    Schulze, R.
    Basic training requirements for the use of dental CBCT by dentists: a position paper prepared by the European Academy of DentoMaxilloFacial Radiology2014In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 43, no 1, article id 20130291Article in journal (Refereed)
    Abstract [en]

    Cone beam CT (CBCT) is a relatively new imaging modality, which is now widely available to dentists for examining hard tissues in the dental and maxillofacial regions. CBCT gives a three-dimensional depiction of anatomy and pathology, which is similar to medical CT and uses doses generally higher than those used in conventional dental imaging. The European Academy of DentoMaxilloFacial Radiology recognizes that dentists receive training in two-dimensional dental imaging as undergraduates, but most of them have received little or no training in the application and interpretation of cross-sectional three-dimensional imaging. This document identifies the roles of dentists involved in the use of CBCT, examines the training requirements for the justification, acquisition and interpretation of CBCT imaging and makes recommendations for further training of dentists in Europe who intend to be involved in any aspect of CBCT imaging. Two levels of training are recognized. Level 1 is intended to train dentists who prescribe CBCT imaging, such that they may request appropriately and understand the resultant reported images. Level 2 is intended to train to a more advanced level and covers the understanding and skills needed to justify, carry out and interpret a CBCT examination. These recommendations are not intended to create specialists in CBCT imaging but to offer guidance on the training of all dentists to enable the safe use of CBCT in the dentoalveolar region.

  • 7.
    Christell, Helena
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Birch, Stephen
    Hedesiu, Mihaela
    Horner, Keith
    Ivanauskaité, Deimante
    Nackaerts, Olivia
    Rohlin, Madeleine
    Malmö högskola, Faculty of Odontology (OD).
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    SEDENTEXCT consortium,
    Variation in costs of cone beam CT examinations among health care systems2012In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 41, no 7, p. 571-577Article in journal (Refereed)
    Abstract [en]

    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 J148 000–227 000). Variation in indirect costs were mainly owing to examination fees (range J0–102.02). 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.

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  • 8. Custódio, Antônio Luís Neto
    et al.
    Cameron, Andrew
    Bakr, Mahmoud
    Little, Chris
    Chrcanovic, Bruno Ramos
    Malmö University, Faculty of Odontology (OD). Malmö University, Biofilms Research Center for Biointerfaces.
    Reher, Peter
    Positioning accuracy assessment of minimally invasive percutaneous injection techniques for the treatment of temporomandibular disorders.2021In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 50, no 2, article id 20200313Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE:

    The aim of the present study was to evaluate the accuracy of an extraoral CBCT-planned 3D-printed surgical guide aimed to percutaneous injection of substances into the temporomandibular joint (TMJ) and the lateral pterygoid muscle (LPM).

    METHODS:

    Nine human cadaver heads were used. Pre-planning CBCT and facial scans were obtained and three percutaneous injection sites were planned: one for the lower compartment of the TMJ and two for the LPM. A digital surgical guide was then designed with small titanium sleeves and printed by a 3D printer. After the injections, new CBCT scans with the needles in place were obtained in order to assess the accuracy of the procedure in relation to the virtual planning.

    RESULTS:

    The mean values for angle deviation were very low (range 1.13o-4.08o), the same happening for the mean difference in the length reached (range 1.82–2.64 mm), as well as for the mean difference in the needle tip dislocation (range 0.94–2.03 mm).

    CONCLUSION:

    The guide seems to be a reliable tool for accurate percutaneous injection of drugs into the inferior compartment of the TMJ and the LPM. Further studies are necessary to test the efficacy and validate the method in an in vivo study.

  • 9.
    Fischer, Johannes
    et al.
    Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
    Halbig, Josefine
    Public Dental Service Competence Centre of Northern-Norway (TkNN), Tromsø, Norway.
    Augdal, Thomas
    Department of Radiology, University Hospital of North Norway, Tromsø, Norway;UiT the Arctic University of North Norway, Tromsø, Norway.
    Angenete, Oskar
    Department of Radiology and Nuclear Medicine, St. Olav University Hospital, Olav Kyrres gate, Trondheim, Norway;Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Faculty of Medicine, Trondheim, Norway.
    Stoustrup, Peter Bangsgaard
    Section of Orthodontics, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark.
    Dahl Kristensen, Kasper
    Section of Orthodontics, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark.
    Slåttelid Skeie, Marit
    Department of Clinical Dentistry, University of Bergen, Bergen, Norway;Center for Oral Health Services and Research, Mid-Norway (TkMidt), Trondheim, Norway.
    Tylleskär, Karin
    The Children’s Clinic at Haukeland University Hospital, Bergen, Norway.
    Rosén, Annika
    Department of Clinical Dentistry, University of Bergen, Bergen, Norway;Department of Oral and Maxillofacial Surgery, Haukeland University Hospital, Bergen, Norway.
    Shi, Xie-Qi
    Malmö University, Faculty of Odontology (OD). Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
    Rosendahl, Karen
    UiT the Arctic University of North Norway, Tromsø, Norway.
    Observer agreement of imaging measurements used for evaluation of dentofacial deformity in juvenile idiopathic arthritis2022In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 51, no 6Article in journal (Refereed)
    Abstract [en]

    Objectives:To examine the precision of imaging measures commonly used to assess mandibular morphology in children and adolescents with juvenile idiopathic arthritis (JIA). Secondly, to compare cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) in the measurement of condylar height.

    Methods:Those included were children diagnosed with JIA during 2015–18 who had had an MRI, a CBCT of the temporomandibular joints (TMJs) and a lateral cephalogram (ceph) of the head within one month of each other. Agreement within and between observers and methods was examined using Bland-Altman mean-difference plots and 95% limits of agreement (LOA). A 95% LOA within 15% of the sample mean was considered acceptable. Minimal detectable change (MDC) within and between observers was estimated.

    Results:90 patients (33 males) were included, with a mean age of 12.8 years. For MRI, intra- and interobserver 95% LOA were relatively narrow for total mandibular length: 9.6% of the sample mean. For CBCT, condylar height, both intra- and interobserver 95% LOA were wide: 16.0 and 28.4% of the sample mean, respectively. For ceph, both intra- and interobserver 95% LOA were narrow for the SNA-angle and gonion angle: 5.9 and 8% of the sample mean, and 6.2 and 6.8%, respectively.

    Conclusions:We have identified a set of precise measurements for facial morphology assessments in JIA, including one MRI-based (total mandibular length), one CBCT-based (condylar height), and three ceph-based. Condylar height was higher for MRI than for CBCT; however, the measurement was too imprecise for clinical use. MDC was also determined for a series of measurements.

  • 10.
    Geraets, Wil GM
    et al.
    Department of Oral and Maxillofacial Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
    Verheij, Johannes GC
    Department of Oral and Maxillofacial Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
    van der Stelt, Paul
    Department of Oral and Maxillofacial Radiology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
    Horner, Keith
    School of Dentistry, Department of Radiology, University of Manchester, UK.
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Nicopoulou-Karayianni, Katy
    Department of Oral Diagnosis and Radiology, University of Athens, Greece.
    Jacobs, Reinhilde
    Oral Imaging Center, University of Leuven, Belgium.
    Marjanovic, Elizabeth
    Department of Imaging Science and Biomedical Engineering, University of Manchester, UK.
    Adams, Judith
    Department of Imaging Science and Biomedical Engineering, University of Manchester, UK.
    Devlin, Hugh
    School of Dentistry, Department of Radiology, University of Manchester, UK.
    Selecting regions of interest on intraoral radiographs for the prediction of bone mineral density2008In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 37, no 7, p. 375-379Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: A previous study showed that the trabecular pattern on dental radiographs correlates with femoral and spinal bone mineral density (BMD). The objective of this study was to determine if the correlation is affected by the size and location of the region of interest (ROI). METHODS: In a European research project on osteoporosis, BMD was measured at the left hip and the lumbar spine of 525 women. From all subjects, intraoral radiographs were made of the premolar region in the upper and lower jaws. Two ROIs were indicated manually on each scanned image. The smallest region involved only trabecular bone and the largest also included parts of the neighbouring teeth. The ROIs were subjected to automatic image analysis, yielding 26 measurements per ROI. Stepwise linear regression was used to predict femoral and spinal BMD. RESULTS: Inner and outer regions predicted BMD equally well. The radiographs of lower and upper jaw also predicted BMD equally well. Combining inner and outer regions did not improve the prediction of femoral and spinal BMD, but combining lower and upper jaws did. CONCLUSIONS: This study shows that it is possible to include parts of neighbouring teeth in the ROI used to assess the trabecular pattern and predict BMD. This simplifies the process of selecting the ROIs because no efforts have to be made to exclude neighbouring teeth. Combining ROIs of lower and upper jaws significantly improves the prediction of BMD.

  • 11.
    Gullberg, Joanna
    et al.
    Malmö University, Faculty of Odontology (OD).
    Al-Okshi, Ayman
    Department of Oral Medicine and Radiology, Faculty of Dentistry, Sebha University, Sebha, Libya.
    Homar Asan, Dalia
    Malmö University, Faculty of Odontology (OD).
    Zainea, Anita
    Malmö University, Faculty of Odontology (OD).
    Sundh, Daniel
    Sahlgrenska Osteoporosis Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden..
    Lorentzon, Mattias
    Sahlgrenska Osteoporosis Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden; Region Västra Götaland, Department of Geriatric Medicine, Sahlgrenska University Hospital, Mölndal, Sweden; Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC, Australia.
    Lindh, Christina
    Malmö University, Faculty of Odontology (OD).
    The challenge of applying digital image processing software on intraoral radiographs for osteoporosis risk assessment2021In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 51, no 1, article id 20210175Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The purpose of this study was to evaluate rater agreement and the accuracy of a semi-automated software and its fully automated tool for osteoporosis risk assessment in intraoral radiographs.

    METHODS: A total of 567 intraoral radiographs was selected retrospectively from women aged 75-80 years participating in a large population-based study (SUPERB) based in Gothenburg, Sweden. Five raters assessed participants' risk of osteoporosis in the intraoral radiographs using a semi-automated software. Assessments were repeated after 4 weeks on 121 radiographs (20%) randomly selected from the original 567. Radiographs were also assessed by the softwares' fully automated tool for analysis.

    RESULTS: Overall interrater agreement for the five raters was 0.37 (95% CI 0.32-0.41), and for the five raters with the fully automated tool included as 'sixth rater' the overall Kappa was 0.34 (0.30-0.38). Intrarater agreement varied from moderate to substantial according to the Landis and Koch interpretation scale. Diagnostic accuracy was calculated in relation to reference standard for osteoporosis diagnosis which is T-score values for spine, total hip and femoral neck and presented in form of sensitivities, specificities, predictive values, likelihood ratios and odds ratios. All raters' mean sensitivity, including the fully automated tool, was 40,4% (range 14,3%-57,6%). Corresponding values for specificity was 69,5% (range 59,7%-90,4%). The diagnostic odds ratios ranged between 1 and 2.7.

    CONCLUSION: The low diagnostic odds ratio and agreement between raters in osteoporosis risk assessment using the software for analysis of the trabecular pattern in intraoral radiographs shows that more work needs to be done to optimise the automation of trabecular pattern analysis in intraoral radiographs.

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  • 12.
    Gullberg, Joanna
    et al.
    Malmö University, Faculty of Odontology (OD).
    Sundh, Daniel
    University of Gothenburg.
    Johansson, Lisa
    University of Gothenburg; Sahlgrenska University Hospital.
    Isberg, Per-Erik
    Lund University.
    Lorentzon, Mattias
    University of Gothenburg; Sahlgrenska University Hospital; Australian Catholic University, Melbourne, Australia.
    Lindh, Christina
    Malmö University, Faculty of Odontology (OD).
    The outcome of an automated assessment of trabecular pattern in intraoral radiographs as a fracture risk predictor.2022In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 51, no 5, article id 20210483Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: This study aims to investigate if automated analyses of the trabecular pattern in intraoral radiographs independently contribute to fracture risk assessment when other risk factors incorporated in the Fracture Risk Assessment Tool (FRAX) are taken into account. A secondary aim is to explore the correlation between the automated trabecular pattern assessment in intraoral radiographs and Trabecular Bone Score (TBS).

    METHODS: A total of 567 intraoral radiographs from older females participating in a large population-based study (SUPERB) based in Gothenburg, Sweden, were selected to analyse trabecular pattern using semi-automated and fully automated software. Associations between trabecular pattern analysis and incident fractures were studied using Cox proportional hazard model, unadjusted and adjusted for FRAX risk factors (previous fracture, family history of hip fracture, smoking, corticosteroids, rheumatoid arthritis, without and with bone mineral density (BMD) of the femoral neck). In addition, the correlation between trabecular pattern analysis and TBS of the lumbar spine was investigated using Pearson correlation analysis.

    RESULTS: Neither the unadjusted nor the adjusted trabecular pattern analysis in intraoral radiographs was significantly associated with any fracture or major osteoporotic fracture (MOF). A weak correlation was found between semi-automated trabecular pattern analysis and TBS. No correlation was found between the fully automated trabecular pattern analysis and TBS.

    CONCLUSIONS: The present study shows that semi-automated and fully automated digital analyses of the trabecular pattern in intraoral radiographs do not contribute to fracture risk prediction. Furthermore, the study shows a weak correlation between semi-automated trabecular pattern analysis and TBS.

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  • 13.
    Hellén-Halme, Kristina
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Hollender, Lars
    Janda, Martin
    Petersson, Arne
    Malmö högskola, Faculty of Odontology (OD).
    Web-based calibration of observers using MRI of the temporomandibular joint2012In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 41, no 8, p. 656-661Article in journal (Refereed)
    Abstract [en]

    Objectives Research diagnostic criteria for temporomandibular disorders (RDC/TMDs) were proposed in 1992 with the aim of standardizing and testing methods for diagnosing TMDs. RDC/TMDs have so far been lacking standardized methods for imaging and criteria for imaging diagnosis of disorders of the temporomandibular joint (TMJ). Criteria for disorders of the TMJ have recently been proposed for MRI. The aim of this study was to publish MR images of the TMJ on the web and to test the agreement of five observers using the criteria. Methods 20 cases of MRI of the TMJ were published on the web together with the criteria. The MR images were taken in closed and open mouth positions, and sagittal and coronal views. Five observers diagnosed disc position, disc shape, joint effusion and loose calcified bodies in the TMJ. Results In all cases except one, three or more observers agreed upon the diagnosis. All agreed on whether a loose calcified body was present or not. The second best agreement was obtained for disc position in the sagittal view, where all observers agreed in 16 of the 20 cases. For disc position in the coronal view and the evaluation of the disc shape, observer agreement was lower. Conclusion Criteria were useful in order to standardize and simplify evaluation and thereby probably increase the diagnostic outcome among different observers for MRI of the TMJ. We recommend that the criteria be used internationally to facilitate comparisons between different studies.

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  • 14.
    Hellén-Halme, Kristina
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Lith, Agneta
    Carious lesions: diagnostic accuracy using pre-calibrated monitor in various ambient light levels: an in vitro study2013In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 42, no 8, article id 20130071Article in journal (Refereed)
    Abstract [en]

    Objectives: This study investigated the effect of different monitor calibration modes under various ambient lighting conditions on the ability of observers to recognize proximal carious lesions of varying depths. Methods: 7 observers evaluated 100 teeth for proximal carious lesions on standardized digital radiographs using 3 set-ups: (1) pre-calibrated monitor for high ambient light (higher than 1000 lux), (2) pre-calibrated monitor for low ambient light (less than 50 lux) and (3) Barten calibration (Digital Imaging and Communication in Medicine) on the monitor in dimmed ambient light (less than 50 lux). Receiver operating characteristic curves were plotted for all observations. The criterion standard was histological examination of the teeth. The effects of three conditions were compared using a paired t-test. The level of significance was set to p , 0.05. Results: No significant difference was found in diagnostic accuracy for the detection of any type of proximal carious lesions between the different calibration modes of the monitor according to different ambient light levels. Conclusions: There is no evidence that any difference between ambient light levels affects the ability to detect carious lesions in digital radiographs as long as the monitor was calibrated in accordance with the surrounding light level.

  • 15.
    Hellén-Halme, Kristina
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Lith, Agneta
    Effect of ambient light level at the monitor surface on digital radiographic evaluation of approximal carious lesions: an in vitro stud2012In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 41, no 3, p. 192-196Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: This study investigated how ambient light affects the diagnostic accuracy of dental carious lesions on monitors used in dental practice. Specifically, the aim was to evaluate whether a monitor hood for blocking excess ambient light increases practitioners' ability to accurately diagnose carious lesions on digital radiographs under bright ambient light conditions. METHODS: 7 observers evaluated approximal carious lesions on standardized digital radiographs of 100 teeth under 3 ambient light conditions: bright light (> 1000 lx) and dim light (<50 lx) with no monitor hood; and bright light with a hooded monitor. Receiver operating characteristic curves were plotted for all observations. The criterion standard was a histological examination of the teeth. A paired t-test compared the effects of the three lighting conditions. The level of significance was set to p <0.05. Weighted kappa statistics estimated intraobserver agreement. RESULTS: The diagnostic accuracy for dentine lesions was significantly higher in ambient light<50&hairsp ;lx than on monitors with and without a hood in ambient light>1000 lx. For all observers, diagnostic accuracy of dentine lesions under bright light was higher on a hooded monitor than on a monitor without a hood, but this difference was not significant. Intraobserver agreement varied from moderate to good. CONCLUSION: Diagnostic accuracy of those carious lesions that reached into the dentine was significantly higher in ambient light<50 lx than in ambient light>1000 lx. A hooded monitor in bright light was not as effective as a monitor without a hood in dim light

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  • 16.
    Hellén-Halme, Kristina
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Nilsson, Mats
    Malmö högskola, Faculty of Odontology (OD).
    Petersson, Arne
    Malmö högskola, Faculty of Odontology (OD).
    Digital radiography in general dental practice. A field study2007In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 36, no 5, p. 249-255Article in journal (Refereed)
    Abstract [en]

    Abstract Objectives: The aim of this study was to conduct a field study to survey the performance of digital radiography and how it was used by dentists in general dental practice. Methods: Nineteen general dental practitioners were visited at their clinics. Ambient light (illuminance) was measured in the rooms where the monitors were placed. Different technical display parameters were noted. Test images and two phantoms—one low-contrast phantom and one line-pair resolution phantom—were used to evaluate the digital system. How the dentists used the enhancement program was investigated by noting which functions were used. Results: Average illuminance in the operating room was 668 lux (range 190–1250 lux). On radiographs of the low-contrast phantom taken at the clinic, the ability to observe the holes decreased as illuminance increased. On average, the “light percentage” initially set on the monitor had to be decreased by 17% and contrast by 10% to optimise the display of the test images. The general dental practitioners used the enhancement programs most often to alter brightness and contrast to obtain the subjectively best image. Large differences between the clinics were noted. Conclusion: Knowledge of how to handle digital equipment in general dental practice should be improved. A calibrated monitor of good quality should be a given priority, as should proper ambient light conditions. There is a need to develop standardised quality controls for digital dental radiography. Key-words: display monitor, enhancement program, digital radiography, quality

  • 17.
    Hellén-Halme, Kristina
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Petersson, Arne
    Malmö högskola, Faculty of Odontology (OD).
    Warfvinge, Gunnar
    Malmö högskola, Faculty of Odontology (OD).
    Nilsson, Mats
    Malmö högskola, Faculty of Odontology (OD).
    Effect of ambient light and monitor brightness and contrast settings on the detection of approximal caries in digital radiographs: an in vitro study2008In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 37, no 7, p. 380-384Article in journal (Refereed)
    Abstract [en]

    Objectives: The aim of this study was to investigate how brightness and contrast settings of the display monitor and ambient light level (illuminance) in the viewing room affect the clinician's ability to diagnose carious lesions in digital radiographs. Methods: Standardized radiographs were taken of 100 extracted teeth. Seven observers evaluated the images for approximal carious lesions twice, once under 50 lux and once under 1000 lux room illumination. Monitor brightness and contrast were varied ±50% and ±6%, respectively, to mimic the normal limits of monitor adjustment by an inexperienced user and one optimal setting. This was done by adjusting radiograph brightness and contrast by ±25%. Thus, five radiographs of each tooth were evaluated. Receiver operating characteristic (ROC) analyses were performed. Histological examinations of the teeth served as the criterion standard. A paired t-test was used to evaluate whether differences in the areas under the ROC curves were significant and kappa was used to evaluate intraobserver agreement. Results: When a monitor with optimal brightness and contrast settings was used to detect approximal carious lesions, ambient light levels less than 50 lux were significantly better than levels above 1000 lux (dentin and enamel lesions, P < 0.01; dentin lesions, P < 0.02). Increasing the contrast setting of the monitor by 6% did not change these results; 50 lux was still significantly better than 1000 lux (enamel lesions, P < 0.01; dentin and enamel lesions, P < 0.02) for evaluating radiographs. Intraobserver agreement differed from fair to good. Conclusions: Reducing ambient light to less than 50 lux significantly increased the accuracy of diagnosing approximal carious lesions on a monitor with an optimal brightness setting and an optimal or slightly higher than optimal contrast setting.

  • 18.
    Iskanderani, Durer
    et al.
    Malmö University, Faculty of Odontology (OD).
    Nilsson, Mats
    Malmö University, Faculty of Odontology (OD).
    Alstergren, Per
    Malmö University, Faculty of Odontology (OD).
    Shi, Xie-Qi
    Malmö University, Faculty of Odontology (OD).
    Hellén-Halme, Kristina
    Malmö University, Faculty of Odontology (OD).
    Evaluation of a low-dose protocol for cone beam computed tomography of the temporomandibular joint2021In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 50, no 1Article in journal (Other academic)
  • 19.
    Iskanderani, Durer
    et al.
    Malmö University, Faculty of Odontology (OD).
    Nilsson, Mats
    Malmö University, Faculty of Odontology (OD).
    Alstergren, Per
    Malmö University, Faculty of Odontology (OD).
    Shi, Xie-Qi
    Malmö University, Faculty of Odontology (OD).
    Hellén-Halme, Kristina
    Malmö University, Faculty of Odontology (OD).
    Evaluation of a low-dose protocol for cone beam computed tomography of the temporomandibular joint.2020In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 49, no 6, article id 20190495Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Evaluation of cone beam CT (CBCT) examination with a low-dose scanning protocol for assessment of the temporomandibular joint (TMJ).

    METHODS: 34 adult patients referred for CBCT imaging of the TMJ underwent two examinations with two scanning protocols, a manufacturer-recommended protocol (default) and a low-dose protocol where the tube current was reduced to 20% of the default protocol. Three image stacks were reconstructed: default protocol, low-dose protocol, and processed (using a noise reduction algorithm) low-dose protocol. Four radiologists evaluated the images. The Sign test was used to evaluate visibility of TMJ anatomic structures and image quality. Receiver operating characteristic analyzes were performed to assess the diagnostic accuracy. κ values were used to evaluate intraobserver agreement.

    RESULTS: ) averaged for the low-dose and processed protocols, according to all observers, were 0.931 and 0.941, respectively. Intraobserver agreement was good to very good.

    CONCLUSION: For the CBCT unit used in this study, the low-dose CBCT protocol for TMJ examination was diagnostically comparable to the manufacturer-recommended protocol, but delivered a five times lower radiation dose. There is an urgent need to evaluate protocols for CBCT examinations of TMJ in order to optimize them for a radiation dose as low as diagnostically acceptable (the as low as diagnostically acceptable principle recommended by NCRP).

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  • 20. Lofthag-Hansen, Sara
    et al.
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Petersson, Arne
    Malmö högskola, Faculty of Odontology (OD).
    Radiographic assessment of the marginal bone level after implant treatment: a comparison of periapical and Scanora detailed narrow beam radiography2003In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 32, no 2, p. 97-103Article in journal (Other academic)
    Abstract [en]

    Objectives: To compare assessments of the marginal bone level around dental implants in the mandible using periapical radiography and Scanora detailed narrow beam (DNB) radiography. METHODS: Forty patients treated with Brånemark dental implants in the lower jaw were examined with periapical and Scanora DNB radiography. Ten implants were selected from each of the four dental regions (molar, incisor, canine, premolar), and no more than one implant was selected from the same patient. Seven observers assessed the level of the marginal bone on the mesial and distal surfaces of the implants. Three of the observers made all the assessments twice. RESULTS: Agreement between the methods was 61 %. The highest agreement was found in the molar region. In DNB radiography the marginal bone level was observed to be situated more “coronally” in 17 % and more “apically” in 22 % compared with periapical radiography. The kappa value for interobserver agreement for all observers was 0.33 for periapical radiography and 0.27 for DNB radiography. The weighted kappa value for intraobserver agreement ranged from 0.75 to 0.99 for DNB radiography and from 0.94 to 0.98 for periapical radiography. CONCLUSIONS: Scanora multimodal radiography simplifies examination of implants in the mandible, and observer variation is comparable with that in intraoral periapical radiography.

  • 21. Mota de Almeida, Fernando José
    et al.
    Huumonen, Sisko
    Molander, Anders
    Öhman, Anders
    Kvist, Thomas
    Computed tomography (CT) in the selection of treatment for root-filled maxillary molars with apical periodontitis2016In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 45, no 5, p. 1-5, article id 20150391Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The aims of this study were to evaluate whether the use of CT facilitates agreement among endodontists in selecting treatments for root-filled maxillary molars with apical periodontitis and to assess the efficacy of CT in choosing a treatment for such teeth. METHODS: 39 root-filled maxillary molars from 34 patients with suspected apical periodontitis were independently evaluated by 4 endodontists and 1 postgraduate student (decision-makers). Treatment decisions were made based on intra-oral radiographs and a fictive clinical history. After 1-3 months, the same decision-makers repeated the examination of the same teeth but with additional information from a CT examination. Agreement between decision-makers with or without the availability of the CT results was measured with Cohen's kappa coefficient. Differences in selected treatments with or without accessibility to the CT results were plotted for the same endodontists using descriptive statistics. RESULTS: The agreement in assessments among endodontists was slight or fair before the CT results were available (range: 0.081-0.535). No increase was observed after reviewing the CT results (range: 0.116-0.379). After the use of CT, the treatment plan was changed 38-76% of the time by all decision-makers, and the changes affected 57.8% of the cases in the study. CONCLUSIONS: The endodontists in this study exhibited a low degree of agreement when choosing a treatment for root-filled maxillary molars with apical periodontitis. A CT examination of the investigated teeth did not result in a significantly higher degree of agreement, and CT frequently contributed to a shift in the selected therapy.

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  • 22. Mota de Almeida, Fernando José
    et al.
    Knutsson, Kerstin
    Malmö högskola, Faculty of Odontology (OD).
    Flygare, Lennart
    The effect of cone beam CT (CBCT) on therapeutic decision-making in endodontics2014In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 43, no 4, article id 20130137Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The aim was to assess to what extent cone beam CT (CBCT) used in accordance with current European Commission guidelines in a normal clinical setting has an impact on therapeutic decisions in a population referred for endodontic problems. METHODS: The study includes data of consecutively examined patients collected from October 2011 to December 2012. From 2 different endodontic specialist clinics, 57 patients were referred for a CBCT examination using criteria in accordance with current European guidelines. The CBCT examinations were performed using similar equipment and standardized among clinics. After a thorough clinical examination, but before CBCT, the examiner made a preliminary therapy plan which was recorded. After the CBCT examination, the same examiner made a new therapy plan. Therapy plans both before and after the CBCT examination were plotted for 53 patients and 81 teeth. As four patients had incomplete protocols, they were not included in the final analysis. RESULTS: 4% of the patients referred to endodontic clinics during the study period were examined with CBCT. The most frequent reason for referral to CBCT examination was to differentiate pathology from normal anatomy, this was the case in 24 patients (45% of the cases). The primary outcome was therapy plan changes that could be attributed to CBCT examination. There were changes in 28 patients (53%). CONCLUSIONS: CBCT has a significant impact on therapeutic decision efficacy in endodontics when used in concordance with the current European Commission guidelines.

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  • 23. Nackaerts, Olivia
    et al.
    Jacobs, Reinhilde
    Devlin, Hugh
    Pavitt, Susan
    Bleyen, E
    Yan, B
    Borghs, Herman
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Karayianni, Katy
    van der Stelt, Paul
    Marjanovic, Elizabeth
    Adams, Judith
    Horner, Keith
    Osteoporosis detection using intraoral densitometry2008In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 37, no 5, p. 282-287Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To determine the diagnostic accuracy of mandibular and maxillary bone density in detecting osteoporosis using receiver operating characteristic (ROC) analysis. METHODS: 671 women between 45 years and 70 years of age underwent dual energy X-ray absorptiometry (DXA) of the hip and lumbar spine. This was the gold standard for diagnosing osteoporosis. Intraoral radiography of the upper and lower right premolar region was performed, using an aluminium wedge as a densitometric reference. Jaw bone density was determined using dedicated software. Observer differences and ROC curves were analysed. RESULTS: For detecting osteoporosis using jaw bone density, the area under the ROC curve (A(z)) was 0.705. For separate analysis of mandibular and maxillary films, sensitivity varied from 33.9% to 38.7% and specificity from 83.5% to 85.3% when using a threshold of 4.3 mm Al equivalent. CONCLUSIONS: Density of the premolar region reaches a fair diagnostic accuracy, which might improve when including additional factors in the analysis and refining the densitometric tool.

  • 24. Nackaerts, Olivia
    et al.
    Jacobs, Reinhilde
    Pillen, M
    Engelen, L
    Gijbels, Frieda
    Devlin, Hugh
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Nicopoulou-Karayianni, Kety
    van der Stelt, Paul F
    Pavitt, Susan
    Horner, Keith
    Accuracy and precision of a densitometric tool for jaw bone2006In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 35, no 4, p. 244-248Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To develop a digital densitometric tool for jaw bone to analyse intraoral radiographs. To assess precision and accuracy for this tool and determine the minimal detection threshold for density changes. METHODS: Bone samples deriving from the premolar region of 47 human mandibles were selected for analysis. The samples were obtained from adult cadavers in the department of anatomy (Faculty of Medicine, KULeuven) with ethical approval. Digital radiography was performed on all bone samples. Direct volumetric measurements served as gold standard density values and allowed determination of accuracy. Dual-energy X-ray absorptiometry (DXA) scans were performed on all specimens. For all radiographs, density in mm Al eq was calculated using custom-made software, Osteop. Precision and intraobserver and interobserver reliability of this method were assessed. The bone specimens were progressively decalcified. At standard time intervals the percentage of decalcification was calculated. At each decalcification step, radiographs were taken and analysed. RESULTS: CV was always lower than 3%, which points to a good precision of the method. Correlation between the density measurements in mm Al eq and the DXA results was 0.9, for the density measurements in mm Al eq and the direct density measurements r was 0.5. The custom-made software was able to detect a change in bone mineralization of 6.6%. CONCLUSIONS: The present method for bone densitometric analysis offers potentials for clinical evaluation of bone density and minute bone density changes in the jaw bone.

  • 25.
    Olsson, Lars
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Nilsson, Mats
    Malmö högskola, Faculty of Odontology (OD).
    Svensson, Björn
    Hellén-Halme, Kristina
    Malmö högskola, Faculty of Odontology (OD).
    The effect of anatomical noise on perception of low contrast in intra-oral radiographs: an in vitro study2016In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 54, no 4, article id 20150402Article in journal (Refereed)
    Abstract [en]

    and discussed of these is random noise. However, recent research has shown that the projected anatomy contributes substantially to noise, especially when detecting low-contrast objects in the images. Our aim, therefore, was to evaluate the extent to which overprojected anatomical noise affects the detection of low-contrast objects in intra-oral images. Methods: Our study used four common sensor models. With each sensor, we took four series of images, three series with and one series without an anatomical phantom present. In each series, we exposed a low-contrast phantom at 18 different exposure times using a standardized method. 4 observers evaluated all 288 images. Results: The low-contrast characteristics differed substantially when imaging low contrast on a homogeneous background compared with imaging low contrast when an anatomical phantom was present. For three of the sensors, optimal exposure times for low-contrast imaging were found, while the fourth sensor displayed a completely different behaviour. Conclusions: Calibrating the low-contrast properties of an imaging system using lowcontrast objects on a homogeneous background is not recommended. On an anatomical background, low-contrast properties are completely different, and these will mimic the clinical situation much more closely, directing the operator how to best use the system. There is a clear demand for further research on this subject. Dentomaxillofacial Radiology (2016) 45, 20150402. doi: 10.1259/dmfr.20150402

  • 26.
    Panmekiate, S.
    et al.
    Department of Radiology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
    Apinhasmit, W.
    Department of Anatomy, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
    Petersson, Arne
    Malmö högskola, Faculty of Odontology (OD).
    Effect of electric potential and current on mandibular linear measurements in cone beam CT2012In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 41, no 7, p. 578-582Article in journal (Refereed)
    Abstract [en]

    Objectives The purpose of this study was to compare mandibular linear distances measured from cone beam CT (CBCT) images produced by different radiographic parameter settings (peak kilovoltage and milliampere value). Methods 20 cadaver hemimandibles with edentulous ridges posterior to the mental foramen were embedded in clear resin blocks and scanned by a CBCT machine (CB MercuRayTM; Hitachi Medico Technology Corp., Chiba-ken, Japan). The radiographic parameters comprised four peak kilovoltage settings (60 kVp, 80 kVp, 100 kVp and 120 kVp) and two milliampere settings (10 mA and 15 mA). A 102.4 mm field of view was chosen. Each hemimandible was scanned 8 times with 8 different parameter combinations resulting in 160 CBCT data sets. On the cross-sectional images, six linear distances were measured. To assess the intraobserver variation, the 160 data sets were remeasured after 2 weeks. The measurement precision was calculated using Dahlberg's formula. With the same peak kilovoltage, the measurements yielded by different milliampere values were compared using the paired t-test. With the same milliampere value, the measurements yielded by different peak kilovoltage were compared using analysis of variance. A significant difference was considered when p < 0.05. Results Measurement precision varied from 0.03 mm to 0.28 mm. No significant differences in the distances were found among the different radiographic parameter combinations. Conclusions Based upon the specific machine in the present study, low peak kilovoltage and milliampere value might be used for linear measurements in the posterior mandible.

  • 27.
    Petersson, Arne
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Eriksson, Lars
    Malmö högskola, Faculty of Odontology (OD).
    Westesson, Per-Lennart
    MR images mimic disc after discectomy2005In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 34, no 4, p. 237-239Article in journal (Other academic)
    Abstract [en]

    MRI of a 30-year-old woman 1 year after discectomy showed a residual disc-like tissue. The observation was initially confusing, but a close comparison of pre- and post-operative images suggested that the inferior wall of the anterior joint capsule had migrated superiorly after the removal of the disc and mimicked a residual disc on the follow-up MR images.

  • 28.
    Rohlin, Madeleine
    et al.
    Malmö University, Faculty of Odontology (OD).
    Horner, Keith
    Lindh, Christina
    Malmö University, Faculty of Odontology (OD).
    Wenzel, Ann
    Through the quality kaleidoscope: reflections on research in dentomaxillofacial imaging2020In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 49, no 6, article id 20190484Article in journal (Refereed)
    Abstract [en]

    The REduce research Waste And Reward Diligence statement has highlighted how weaknesses in health research can produce misleading results and waste valuable resources. Research on diagnostic efficacy in the field of dentomaxillofacial radiology (DMFR) is no exception to these criticisms and could be strengthened by more robust study designs, consistent use of a core set of outcome measures and completeness in reporting. Furthermore, we advocate that everyone participating in collaborative research on clinical interventions subscribes to the importance of methodological quality in how imaging methods are used. The aim of this paper, therefore, is to present a guide to conducting high-quality research on diagnostic efficacy in DMFR.We initially propose a framework inspired by the hierarchical model of efficacy of Fryback and Thornbury, highlighting study designs, measures of analysis, completeness of reporting and established guidelines to assist in these aspects of research. Bias in research, and measures to prevent or limit it, are then described.It is desirable to climb the Fryback and Thornbury "ladder" from technical efficacy, via accuracy and clinical efficacy, to societal efficacy of imaging methods. Efficacy studies on the higher steps of the ladder may be difficult to perform, but we must strive to answer questions of how useful our methods are in patient management and assess benefits, risks, costs, ethical and social issues. With the framework of six efficacy levels as the structure and based on our experience, we present information that may facilitate quality enhancement of diagnostic efficacy research in DMFR.

  • 29.
    Senneby, Anna
    et al.
    Malmö högskola, Faculty of Odontology (OD).
    Elfvin, Margareta
    Stebring-Franzon, Christina
    Rohlin, Madeleine
    Malmö högskola, Faculty of Odontology (OD).
    A novel classification system for assessment of approximal caries lesion progression in bitewing radiographs2016In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 45, no 5, article id 20160039Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To design and pilot a novel classification system for the assessment of caries lesion progression in bitewing radiography and to report rater agreement of the system.

    METHODS: A classification system with drawings and text was designed to assess caries lesion progression. Guidelines for Reporting Reliability and Agreement Studies were used to study and report rater agreement. Pairs of posterior bitewing radiographs (baseline and 1-year follow-up) with different status concerning caries lesion progression were selected from files from public dental health clinics. 10 raters, 5 general dental practitioners and 5 specialists in oral and maxillofacial radiology were asked to assess the radiographs with the aid of the classification system. Seven raters repeated their assessments. Rater agreement was expressed as percentage of agreement and kappa.

    RESULTS: Kappa for the interrater agreement of 10 raters assessing progression was 0.61, indicating substantial agreement. Agreement was moderate for progression in the outer half of the dentine (kappa 0.55) and within enamel (kappa 0.44). Pairwise interrater agreement varied (range 69-92%; kappa 0.42-0.84). For about half of the pairs of raters, kappa was substantial (≥0.61). Intrarater agreement assessing progression was substantial (kappa 0.66-0.82).

    CONCLUSIONS: We demonstrated the applicability of the proposed classification system on caries lesion progression with respect to rater agreement. This system can provide a common framework for clinical decision-making on caries interventional methods and patient visiting intervals. Scientifically, this system allows for a comparative analysis of different methods of prevention and treatment of caries as well as of different caries risk assessment methods.

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  • 30.
    Shi, Xie-Qi
    et al.
    Univ Bergen, Sect Oral Maxillofacial Radiol, Dept Clin Dent, Fac Med, Bergen, Norway..
    Hellén-Halme, Kristina
    Malmö University, Faculty of Odontology (OD).
    Nilsson, Mats
    Skane Univ Hosp, Dept Med Radiat Phys, Malmo, Sweden..
    In response to the letter to the editor regarding "A comparative study on image quality of two digital intraoral sensors-Methodological, ethical and statistical issues"2020In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 49, no 4Article in journal (Other academic)
  • 31. Verheij, Johannes GC
    et al.
    Geraets, Wil GM
    Van der Stelt, Paul
    Horner, Keith
    Lindh, Christina
    Malmö högskola, Faculty of Odontology (OD).
    Nikopoulou-Karayianni, Katy
    Jacobs, Reinhilde
    Marjanovic, Elizabeth
    Adams, Judith
    Devlin, Hugh
    Prediction of osteoporosis with dental radiographs and age2009In: Dento-Maxillo-Facial Radiology, ISSN 0250-832X, E-ISSN 1476-542X, Vol. 38, no 7, p. 431-437Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: In this study age and the trabecular pattern present on dental radiographs were used to predict the presence of osteoporosis. The objective was to evaluate the contribution of the trabecular pattern to the prediction. METHODS: In this project, 671 women between 45 and 71 years of age were recruited. Medical history was obtained and dental radiographs were made. Bone mineral density (BMD) was measured at three sites to assess the presence of osteoporosis according to the World Health Organization criteria. The radiographs were subjected to image analysis methods yielding measurements of the trabecular pattern. Thereafter, discriminant analysis was used to predict the presence of osteoporosis by means of the trabecular pattern and age. Sensitivity and specificity of age and the trabecular pattern were compared. Also, it was checked whether the inclusion of the trabecular pattern improved the sensitivity and specificity that were obtained when only age was used as the predictor. RESULTS: The sensitivity and specificity of the trabecular pattern present on dental radiographs were almost equal to those of age. However, combining age with the trabecular pattern increased the sensitivity from 0.71 to 0.75 and the specificity from 0.72 to 0.78; the latter increase was statistically significant. CONCLUSIONS: The trabecular pattern predicts the presence of osteoporosis just as well as age does. When combining the trabecular pattern with age, the sensitivity and specificity increased. Only the latter increase was statistically significant.

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