SwePub - sökning: WFRF:(Gröndahl Hans Göran 1940...

Numrering	Referens	Omslagsbild	Hitta
1.	Economopoulos, TL, et al. (författare) A contrast correction method for dental images based on histogram registration 2010 Ingår i: Dentomaxillofacial Radiology. - : British Institute of Radiology. - 0250-832X .- 1476-542X. ; 39:5, s. 300-313 Tidskriftsartikel (refereegranskat)abstract Contrast correction is often required in digital subtraction radiography when comparing medical data acquired over different time periods owing to dissimilarities in the acquisition process. This paper focuses on dental radiographs and introduces a novel approach for correcting the contrast in dental image pairs. The proposed method modifies the subject images by applying typical registration techniques on their histograms. The proposed histogram registration method reshapes the histograms of the two subject images in such a way that these images are matched in terms of their contrast deviation. The method was extensively tested over 4 sets of dental images, consisting of 72 registered dental image pairs with unknown contrast differences as well as 20 dental pairs with known contrast differences. The proposed method was directly compared against the well-known histogram-based contrast correction method. The two methods were qualitatively and quantitatively evaluated for all 92 available dental image pairs. The two methods were compared in terms of the contrast root mean square difference between the reference image and the corrected image in each case. The obtained results were also verified statistically using appropriate t-tests in each set. The proposed method exhibited superior performance compared with the well-established method, in terms of the contrast root mean square difference between the reference and the corrected images. After suitable statistical analysis, it was deduced that the performance advantage of the proposed approach was statistically significant.
2.	Economopoulos, T, et al. (författare) Automatic correspondence using the enhanced hexagonal center-based inner search algorithm for point-based dental image registration 2006 Ingår i: Conf Proc IEEE Eng Med Biol Soc. ; 1, s. 1421-1424 Tidskriftsartikel (refereegranskat)abstract In this paper a modified version of the center-based inner search algorithm, the enhanced hexagonal center-based inner search algorithm, for automatic point correspondence is proposed towards dental registration. The modified algorithm is incorporated within a general registration scheme which is based on extracting a set of candidate points on the reference image, finding their corresponding points in the other image (float image) using the proposed algorithm and applying an affine geometrical transformation towards automatic registration. The performance of the proposed algorithm is evaluated against a well-known method for automatic correspondence, in terms of the registration accuracy. Qualitative and quantitative results on registering 24 dental pairs showed that the proposed algorithm outperforms the other method for automatic correspondence.
3.	Economopoulos, T, et al. (författare) Automatic correspondence using the enhanced hexagonal centre-based inner search algorithm for point-based dental image registration 2008 Ingår i: Dentomaxillofacial Radiology. - : British Institute of Radiology. - 0250-832X .- 1476-542X. ; 37, s. 185-204 Tidskriftsartikel (refereegranskat)abstract Objectives: In this paper, the enhanced hexagonal centre-based inner search (EHCBIS) algorithm, for automatic point correspondence, is proposed for dental image registration. Methods: The presented algorithm is incorporated within a general registration scheme, which is based on extracting a set of candidate points on the reference image, finding their corresponding points in the image to be transformed (float image) using the proposed algorithm and applying a suitable geometrical transformation towards automatic registration. The performance of the proposed algorithm is evaluated against three well-known methods for automatic correspondence, the self-organizing maps, the automatic extraction of corresponding points and the trimmed iterative closest point method, in terms of registration accuracy. Results: Qualitative and quantitative results on registering 123 dental pairs show that the proposed algorithm outperforms the other methods for automatic correspondence with or without the presence of noise. Conclusions: The EHCBIS method is capable of defining automatically corresponding points in dental image pairs. It can be incorporated within a general scheme for point-based registration of dental radiographs acquired with or without rigorous a priori standardization. The applied projective transformation provides a reliable model for registering intraoral radiographs. The methodology does not require any segmentation prior to alignment providing subtraction radiographs and fused images for clinical evaluation regarding the evolution of a disease or the response to a therapeutic scheme.
4.	Ekestubbe, Annika, 1953, et al. (författare) Low-dose tomographic techniques for dental implant planning. 1996 Ingår i: The International journal of oral & maxillofacial implants. - 0882-2786. ; 11:5, s. 650-9 Tidskriftsartikel (refereegranskat)abstract Image quality in preimplant computerized tomography (CT) examinations made with different radiation doses (40 to 280 mAs) and scanning modes (standard and helical axial, 15-degree angled, and frontal) and in conventional spiral tomography (Scanora) was compared. Mandibular canal and alveolar bone crest visibility was evaluated in images from mandibular jaw segments. Visibility was unaffected by radiation dose in CT examinations except in frontal scanning, where a small actual difference was statistically significant. Differences among CT scanning modes and between CT and conventional spiral tomography were highly significant. Low-dose mandibular preimplant tomography can be performed with CT using lower-than-normal radiation doses or with conventional spiral tomography.
5.	Ekestubbe, Annika, 1953, et al. (författare) Oral radiologi 2005 Bok (övrigt vetenskapligt/konstnärligt)
6.	Ekestubbe, Annika, 1953, et al. (författare) Quality of preimplant low-dose tomography. 1999 Ingår i: Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics. - 1079-2104. ; 88:6, s. 738-44 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: The aim of this study was to test the influence of radiation dose on image quality in mandibular preimplant computed tomographic examinations and to compare the quality of computed and conventional spiral tomographic images. STUDY DESIGN: Cross-sectional images were obtained on 17 patients with conventional spiral tomography (Scanora technique) and reformatted computed tomography at 40 and 80 mAs. Observers graded the acceptability of images for implant planning and traced the contour of the mandibular body and canal. RESULTS: Conventional spiral tomographic images scored significantly higher than computed tomographic images whereas mean score differences between computed tomographic techniques were not statistically significant. Anatomic structures, in particular the mandibular canal, were more frequently untraceable in high-dose than in low-dose computed tomography but always traceable in conventional tomograms. CONCLUSION: Conventional spiral tomograms were subjectively preferred over computed tomographic images. For mandibular implant planning, computed tomography examinations can be performed with lower-than-standard mAs. Quantum noise seems to contribute to the visibility of anatomic structures in reformatted computed tomographic images.
7.	Ekestubbe, Annika, 1953, et al. (författare) The use of tomography for dental implant planning. 1997 Ingår i: Dento maxillo facial radiology. - : British Institute of Radiology. - 0250-832X. ; 26:4, s. 206-13 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: To examine the use of tomography for dental implant planning. METHODS: A questionnaire was sent to oral radiology clinics in Sweden and to implantology clinics in different parts of the world with questions on selection criteria and techniques for, and frequency of, pre-implant tomography. Differences between mean values were assessed by t-test. A new method developed by the Swedish Radiation Protection Institute was used to assess radiation absorbed dose from CT. RESULTS: Tomography was used by 93.4% of the clinics, but there was marked variation both between and within different clinical situations. It was performed in all cases by 21% and the majority used it for the evaluation of the maxilla, the posterior mandible and in single implant cases. Small clinics (< 100 patients per year) used tomography frequently and clinics in Sweden significantly more often than those in other countries. The majority had changed their policy recently, using tomography more often. CT was used by 73% of respondents, mainly the small clinics. The majority of the large clinics (> 500 patients per year) used conventional tomography. The mean absorbed dose for CT scanning protocols was 65 mGy. The variation within and between different makes of CT was considerable. CONCLUSIONS: There are large variations in frequency of use of both conventional and computed tomography for dental implant planning by different clinics who also vary in the indications for their choice. A substantial factor influencing the technique chosen was its availability rather than clinical need.
8.	Gröndahl, Hans-Göran, 1940, et al. (författare) High quality radiology - A sine qua non in planning and monitoring of osseointegration-based treatment in the oro-facial area. 2005 Ingår i: Brånemark, P-I. (red). The osseointegration book : from calvarium to calcaneus. - Berlin : Quintessence. - 1850970904 Bokkapitel (övrigt vetenskapligt/konstnärligt)
9.	Gröndahl, Hans-Göran, 1940, et al. (författare) Radiographic examination of the implant patient 2008 Ingår i: In: Lindhe J, Lang NP, Karring T (eds.). Clinical Periodontology and Implant Dentistry (vol 2), fifth edition. PA: Wiley-Blackwell. Bokkapitel (övrigt vetenskapligt/konstnärligt)
10.	Gröndahl, Hans-Göran, 1940, et al. (författare) Titta på dina bitewingbilder-andra gör det inte! 2005 Ingår i: Tandläkartidningen. ; 97:7, s. 60-66 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract De vanligaste röntgenbilder som tandläkare tar är utan tvivel bitewingbilder. Bitewingbilder kan också tas av en tandhygienist vid uppföljning av revisionspatienter. Bilder som tas av hygienister ska dock lämnas till en tandläkare för diagnostik av annat än karies och benförlust som orsakats av parodontit. Varje år tas flera miljoner bitewingbilder i Sverige. De har huvudsakligen två syften: 1) att vara till hjälp vid kariesdiagnostik och 2) för bedömning av det marginala benet. I den stora mängd bilder som tas dyker det då och då upp tecken på patologiska tillstånd av annan och ibland allvarligare art. Det är viktigt att vara medveten om den risken. Det ökar möjligheten att i ett tidigt stadium uppmärksamma sådana processer. Till en specialistklinik för odontologisk radiologi remitteras huvudsakligen patienter som kräver undersökningar som inte kan utföras i allmänpraktik. Hittar specialisterna en större patologisk process som troligen utvecklats under flera år letar de sig alltid bakåt i tiden. De gör det av två skäl: 1) det underlättar diagnostiken och 2) det ökar kunskaperna om på vilket sätt, och hur snabbt, olika typer av patologiska förändringar utvecklas. Tidigare tagna röntgenbilder och journalanteckningar kan berätta något om symtom eller kliniska tecken. När röntgenbilderna granskas kan specialisterna ibland se att det patologiska tillståndet funnits med i bilden men inte uppmärksammats. På följande sidor presenteras några sådana fall. Författarna spekulerar i varför upptäckterna inte gjordes tidigare och föreslår åtgärder som förhoppningsvis innebär att fler upptäckter kan göras i tidigare sjukdomsstadier. På så sätt kan behandlingen bli enklare och resultatet bättre.
11.	Gröndahl, Kerstin, 1948, et al. (författare) A multimodal unit for comprehensive dento-maxillofacial radiography. 1993 Ingår i: Dental update. - 0305-5000. ; 20:10, s. 436-40 Tidskriftsartikel (refereegranskat)abstract Using the Scanora radiography unit, most radiographic examinations in the dento-maxillofacial region can be rapidly performed to produce exceptionally high quality images. The Scanora unit uses the principles of narrow beam radiography and spiral tomography. Starting with a panoramic overview as a scout image, a large number of dental and maxillofacial imaging procedures and projections can be selected, all of which are computer controlled and automatically executed. The authors provide examples from their experience with over 10,000 patients and more than 30,000 examinations.
12.	Gröndahl, Kerstin, 1948, et al. (författare) Viktigt välja rätt röntgenteknik 2010 Ingår i: Tandläkartidningen. - 0039-6982. ; 102:1, s. 64-71 Tidskriftsartikel (refereegranskat)abstract I takt med att indikationsområdet för implantatbehandling vidgats, har kraven ökat på den information som en röntgenundersökning ska bidra med. Här presenteras de vanligaste röntgenteknikerna och hur de kan användas.
13.	Lofthag-Hansen, Sara, 1956, et al. (författare) Limited cone-beam CT and intraoral radiography for the diagnosis of periapical pathology 2007 Ingår i: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. ; 103:1, s. 114-119 Tidskriftsartikel (refereegranskat)abstract Objective To compare intraoral periapical radiography with 3D images for the diagnosis of periapical pathology. Study design Maxillary molars and premolars and mandibular molars with endodontic problems and examined with periapical radiographs and a 3D technique (3D Accuitomo) were retrospectively selected and evaluated by 3 oral radiologists. Numbers of roots and root canals, presence and location of periapical lesions, and their relation to neighboring structures were studied. Results Among 46 teeth, both techniques demonstrated lesions in 32 teeth, and an additional 10 teeth were found in the Accuitomo images. As regards individual roots, 53 lesions were found in both techniques, and 33 more roots were found to have lesions in Accuitomo images. Artefacts were sometimes a problem in Accuitomo images. In 32 of the 46 cases, all observers agreed that additional clinically relevant information was obtained with Accuitomo images. Conclusions A high-resolution 3D technique can be of value for diagnosis of periapical problems.
14.	Lund, Henrik, 1975, et al. (författare) Accuracy and precision of linear measurements in cone beam computed tomography Accuitomo tomograms obtained with different reconstruction techniques 2009 Ingår i: Dentomaxillofacial Radiology. - 0250-832X. ; 38:6, s. 379-86 Tidskriftsartikel (refereegranskat)abstract Objectives: To assess the accuracy and precision of linear measurements, the influence of different object positions in cone beam CT (CBCT) images and the effect of different systems for reformatting and viewing the tomograms on measurement values. Methods: An object consisting of Plexiglas® plates with metal spheres was radiographically examined in three positions using the CBCT unit Accuitomo®. Tomograms were reformatted using the i-Dixel software and Sectra® picture archiving and communication system (PACS) multiplanar reformatting (MPR). Two observers measured 20 linear distances in axial, frontal and sagittal planes. Physical measurements of actual distances by means of a digital caliper served as the gold standard. Results: For measurements performed on the Accuitomo and Sectra PACS workstations, the mean differences between repeated measurements were below 0.13 mm (standard deviation (SD) 0.13 mm) and 0.21 mm (SD 0.18 mm), respectively. Mean differences between the two observers were below 0.11 mm (SD 0.07 mm) and 0.15 mm (SD 0.09 mm). The mean difference between the gold standard and the basic position when using the Accuitomo workstation, was –0.08 mm (SD 0.21 mm) and for a deviated/rotated position –0.08 mm (SD 0.23 mm) and –0.09 mm (SD 0.20 mm). None was statistically significant (P > 0.05). For measurement performed on MPR tomograms using the Sectra PACS workstation, mean differences were –0.09 mm (SD 0.17 mm) for basic position, and –0.08 mm (SD 0.19 mm) and –0.13 mm (SD 0.15 mm) for deviated and rotated positions, respectively. The mean difference between gold standard and basic/rotated positions was statistically significant, with P = 0.032 and P = 0.002. Conclusions: Our study confirms previous findings indicating that measurements in 3DX Accuitomo FPD (flat panel detector) tomograms show a high level of agreement with actual distances. Our findings suggest the possibility of minor distortion in tomograms reformatted by means of Sectra PACS MPR.
15.	Lund, Henrik, 1975, et al. (författare) Apical root resorption during orthodontic treatment: A prospective study using cone beam CT 2012 Ingår i: The Angle Orthodontist. - : The Angle Orthodontist (EH Angle Education & Research Foundation). - 0003-3219 .- 1945-7103. ; 82:3, s. 480-487 Tidskriftsartikel (refereegranskat)abstract Abstract Objective: To investigate the incidence and severity of root resorption during orthodontic treatment by means of cone beam computed tomography (CBCT) and to explore factors affecting orthodontically induced inflammatory root resorption (OIIRR). Materials and Methods: CBCT examinations were performed on 152 patients with Class I malocclusion. All roots from incisors to first molars were assessed on two or three occasions. Results: At treatment end, 94% of patients had ≥1 root with shortening >1 mm, and 6.6% had ≥1 tooth where it exceeded 4 mm. Among teeth, 56.3% of upper lateral incisors had root shortening >1 mm. Of upper incisors and the palatal root of upper premolars, 2.6% showed root shortenings >4 mm. Slanted surface resorptions of buccal and palatal surfaces were found in 15.1% of upper central and 11.5% of lateral incisors. Monthly root shortening was greater after 6-month control than before. Upper jaw teeth and anterior teeth were significantly associated with the degree of root shortening. Gender, root length at baseline, and treatment duration were not. Conclusion: Practically all patients and up to 91% of all teeth showed some degree of root shortening, but few patients and teeth had root shortenings >4 mm. Slanted root resorption was found on root surfaces that could be evaluated only by a tomographic technique. A CBCT technique can provide more valid and accurate information about root resorption.
16.	Lund, Henrik, 1975, et al. (författare) Cone beam computed tomography evaluations of marginal alveolar bone before and after orthodontic treatment combined with premolar extractions 2012 Ingår i: European Journal of Oral Sciences. - : Wiley. - 0909-8836. ; 120:3, s. 201-211 Tidskriftsartikel (refereegranskat)abstract Using cone beam computed tomography (CBCT) we investigated the distance between the cementoenamel junction (CEJ) and the marginal bone crest (MBC) at buccal, lingual, mesial, and distal surfaces of incisors to first molars in adolescents before (baseline) and after extractive orthodontic treatment (study end point). Patients with Class I malocclusion, crowding and an overjet of =5mm were examined with a CBCT unit using a 60x60-mm field of view and a 0.125-mm voxel size. Large differences in marginal bone height were found at baseline, particularly between tooth surfaces. There was a slight correlation between age and CEJMBC distance. From baseline to the study end point, large bone-height changes among teeth and tooth surfaces could be seen. Lingual surfaces, followed by buccal surfaces, showed the largest changes. Eighty-four per cent of lingual surfaces of mandibular central incisors exhibited a bone-height decrease of >2 similar to mm. The bone-height decrease was larger at lingual surfaces in the mandible than in the maxilla, and larger in girls (mean=1.8mm) than in boys (mean=1.5mm). Fewer than 1% of proximal surfaces exhibited changes of >2mm. It is unknown whether the changes in marginal bone height are transitory. A high-quality CBCT technique may help to determine this by providing a deeper insight into the long-term side effects of orthodontic treatment.
17.	Lund, Henrik, 1975, et al. (författare) Cone beam computed tomography for assessment of root length and marginal bone level during orthodontic treatment 2010 Ingår i: Angle Orthodontist. - : The Angle Orthodontist (EH Angle Education & Research Foundation). - 0003-3219 .- 1945-7103. ; 80:3, s. 466-473 Tidskriftsartikel (refereegranskat)abstract OBJECTIVE: To evaluate the accuracy and precision of cone beam computed tomography (CBCT) with regard to measurements of root length and marginal bone level in vitro and in vivo during the course of orthodontic treatment. MATERIALS AND METHODS: Thirteen patients (aged 12-18 years) from an ongoing study and a dry skull were examined with CBCT using multiplanar reformatting for measurements of root length and marginal bone level. For in vivo evaluation of changes in root length, an index according to Malmgren et al was used, along with a modification of this method. RESULTS: The in vitro mean difference between physical and radiographic measurements was 0.05 mm (SD 0.75) for root length and -0.04 mm (SD 0.54) for marginal bone level. In vivo the error was <0.35 mm for root length determinations and <0.40 mm for marginal bone level assessments. CONCLUSION: Despite changes in tooth positions, the CBCT technique yields a high level of reproducibility, enhancing its usefulness in orthodontic research.
18.	Matsopoulos, GK, et al. (författare) Image registration based on lifting process: an application to digital subtraction radiography 2006 Ingår i: IEEE Trans Inf Technol Biomed. ; 10:4, s. 763-774 Tidskriftsartikel (refereegranskat)abstract In this paper, a digital subtraction radiology scheme is presented based on a new method for the automatic registration of dental radiographs acquired with or without rigorous a priori standardization. The scheme is comprised of an automatic registration method and a subtraction process. The proposed registration method can be considered as an object-based registration method without imposing the prerequisite of image segmentation in order to detect the boundary of the objects of interest or the automatic detection of matching landmarks. This is achieved by augmenting the dimensionality of the problem from two-dimensional gray-level matching to three-dimensional surface matching using the process of lifting in combination with a surface-matching technique. The pseudo three-dimensional affine transformation that matches the lifted images incorporates advantageous characteristics including spatial alignment of the surfaces, anisotropic correction of brightness/contrast differences, and stable convergence of the similarity function to its optimal value. The performance of the proposed automatic registration method is assessed against a manual method based on the projective transformation. The qualitative and quantitative assessments of the experiments have shown advantageous performance of the proposed automatic registration method against the manual one. Finally, the proposed registration method has been further improved in terms of execution time by the implementation of a surface decimation process.
19.	Tanimoto, H, et al. (författare) Further development of a versatile computer-assisted learning program for dental education with an exemplifying application on how to logically arrange and mount periapical and bitewing radiographs 2006 Ingår i: Oral Radiol 2006. ; 22, s. 75-79 Tidskriftsartikel (refereegranskat)abstract Objectives To develop interactive computer-assisted learning software for teaching dental students to logically arrange periapical and bitewing radiographs. Methods Using the Microsoft Visual Basic.NET programming language, we developed software comprising an original object menu window, workspaces, and functions for radiograph shuffling, rotating, mounting, clock, evaluation, score, easy addition of images, a virtual teacher, and help menus. We also developed a program called “Mounting of Dental Radiographs,” which is composed of dental images, a menu window, workspaces, and functions. Results On starting the program, randomly ordered radiographs from a full-mouth X-ray exam are presented, and the clock starts. The student selects one image at a time and places it in the proper folder. An image may need to be rotated or turned. When all images are mounted, the virtual teacher checks the results. If the images have not all been placed correctly within the time limit, the student is given two more attempts before being told, “You lost.” This software can be easily and quickly modified, and dates and scores can be saved automatically. Conclusions We developed a versatile, interactive software program to help students understand how to mount dental X-ray images. It can be modified easily to suit the needs of different students.
20.	Zacharaki, E I, et al. (författare) A digital subtraction radiography scheme based on automatic multiresolution registration. 2004 Ingår i: Dento maxillo facial radiology. - : British Institute of Radiology. - 0250-832X. ; 33:6, s. 379-90 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: To establish a digital subtraction radiography scheme for aligning clinical in vivo radiographs based on the implementations of an automatic geometric registration method and a contrast correction technique. METHODS: Thirty-five pairs of in vivo dental radiographs from four clinical studies were used in this work. First, each image pair was automatically aligned by applying a multiresolution registration strategy using the affine transformation followed by the implementation of the projective transformation at full resolution. Then, a contrast correction technique was applied in order to produce subtraction radiographs and fused images for further clinical evaluation. The performance of the proposed registration method was assessed against a manual method based on the projective transformation. RESULTS: The qualitative assessment of the experiments based on visual inspection has shown advantageous performance of the proposed automatic registration method against the manual method. Furthermore, the quantitative analysis showed statistical difference in terms of the root mean square (RMS) error estimated over the whole images and specific regions of interest. CONCLUSIONS: The proposed automatic geometric registration method is capable of aligning radiographs acquired with or without rigorous a priori standardization. The methodology is pixel-based and does not require the application of any segmentation process prior to alignment. The employed projective transformation provides a reliable model for registering intraoral radiographs. The implemented contrast correction technique sequentially applied provides subtraction radiographs and fused images for clinical evaluation regarding the evolution of a disease or the response to a therapeutic scheme.
21.	Akdeniz, BG, et al. (författare) Accuracy of proximal caries depth measurements: comparison between limited cone beam computed tomography, storage phosphor and film radiography 2006 Ingår i: Caries Res. ; 40:3, s. 202-207 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to compare the accuracy of limited cone beam computed tomography (LCBCT), an image plate system and F-speed film in assessing the depth of proximal carious lesions. Radiographs of a dry mandible with sound and carious teeth were obtained with all three methods. In 41 molar and premolar proximal surfaces, 2 observers independently measured lesion depth on the images from the three modalities. The correlation of measurements was assessed with Pearson's correlation analysis. Results from imaging modalities and histological sectioning (gold standard) were compared using Bland-Altman plots. Overall comparison of the depth measurements from the imaging modalities and the gold standard was done using repeated-measures ANOVA. Pairwise comparisons of systems were done by the Bonferroni t test. The correlation between the measurements of the two observers was 0.977 for film, 0.997 for image plate system and 0.998 for LCBCT. Bland-Altman plots revealed that LCBCT agreed very closely with the gold standard while the agreement between the latter and the image plate--or film--images was moderate. The mean difference and 95% limits of agreement between LCBCT and the gold standard were smaller than those between either image plate or F-speed film and the gold standard. The LCBCT method appears as a promising tool for detection and monitoring of proximal carious lesions.
22.	Akdeniz, BG, et al. (författare) Degradation of storage phosphor images due to scanning delay 2006 Ingår i: Dentomaxillofac Radiol. ; 35:2, s. 74-77 Tidskriftsartikel (refereegranskat)abstract OBJECTIVE: To evaluate the degradation of storage phosphor images relative to scanning delay. METHODS: A series of exposures of an aluminium step-wedge with five 2 mm incremental steps were made using blue Digora storage phosphor plates (SPPs). After the first exposure the plates were immediately scanned. After the second the plates were scanned after a half hour delay, after the third after a 1 h delay and so on until a final delay of 8 h. Mean grey values (MGVs) of each step of the wedge and its background were compared using repeated measures analysis of variance (ANOVA). Difference between group means was assessed using Bonferroni/Dunn multiple comparison test (P<0.05). RESULTS: MGVs increased with the increase in scan delay. Repeated measures ANOVA revealed that MGVs of the background and each step of the wedge were significantly different from each other for all scan delays (P<0.0001). Bonferroni/Dunn test showed that MGVs from plates scanned half an hour after exposure were not significantly different from those scanned immediately (P>0.05). Longer delays gave rise to significant differences in MGVs (P<0.05). CONCLUSION: Digora SPPs show statistically significant degradation of grey level values and contrast in plates scanned half an hour or longer after exposure.
23.	Akdeniz, B Güniz, et al. (författare) Effect of delayed scanning of storage phosphor plates. 2005 Ingår i: Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics. - : Elsevier BV. - 1528-395X .- 1079-2104. ; 99:5, s. 603-7 Tidskriftsartikel (refereegranskat)abstract OBJECTIVE: To test longevity of image quality in storage phosphor plates (SPPs) at various exposure settings, storage conditions, and delays in scanning. STUDY DESIGN: Fifteen Digora plates were exposed from 0.08 to 0.20 seconds and scanned immediately, 10, 30, and 60 minutes, and 24 hours after exposure. Plates were stored both in daylight and in a light-tight box. Mean gray values (MGVs) were compared using 2 x 5 x 5 factorial ANOVA. Interaction between variables was tested using Bonferroni/Dunn multiple comparisons test. RESULTS: MGVs decreased with increase in exposure but increased with the scan delay. Only MGVs of plates scanned within 10 minutes after exposure were not significantly different from the ones scanned immediately ( P > .05). MGVs increased with scan delay for all exposure times no matter how the plates were stored ( P < .05). CONCLUSION: Based on the time delays examined, it is recommended to scan the Digora SPP no later than 10 minutes after exposure. Longer periods may cause loss of quality.
24.	Bælum, Vibeke, et al. (författare) The foundations of good diagnostic practice? 2008 Ingår i: Dental caries, The disease and its clinical management. - Oxford : Blackwell Publishing. ; , s. 103-118 Bokkapitel (övrigt vetenskapligt/konstnärligt)
25.	Baksi, BG, et al. (författare) LCD and CRT display of storage phosphor plate and limited cone beam computed tomography images for the evaluation of root canal fillings 2009 Ingår i: Clinical oral investigations. - : Springer Science and Business Media LLC. - 1432-6981 .- 1436-3771. ; 13:1, s. 37-42 Tidskriftsartikel (refereegranskat)abstract The aim was to compare quality of liquid crystal display (LCD) and high resolution cathode ray tube (CRT) screens for the evaluation of length and homogeneity of root canal fillings in storage phosphor plate (SPP) and limited cone beam computed tomography (LCBCT) images. Endodontic treatment was performed to 17 extracted permanent lower incisor teeth. Images of each tooth positioned in a dried mandible were obtained with Digora® SPP and Accu-I-Tomo LCBCT systems. Six observers scored the quality of all images on CRT and LCD screens. Results were compared using McNemar’s and Cochran’s Q tests (p <0.05). The differences among the LCBCT and SPP images were determined by binomial test. No significant difference was found between ratings of CRT and LCD displays (p>0.05). Agreement among observers’ scores was higher with CRT display. Within the limits of this ex vivo study, differences between LCD and CRT monitors for the evaluation of root canal fillings are clinically insignificant independent on whether conventional radiographs, captured by means of image plates, or cone beam images are being displayed.
26.	Deserno, TM, et al. (författare) Content-based access to oral and maxillofacial radiographs 2007 Ingår i: Dentomaxillofac Radiol. ; 36:6, s. 328-335 Tidskriftsartikel (refereegranskat)abstract Objectives: Content-based access (CBA) to medical image archives, i.e. data retrieval by means of image-based numerical features computed automatically, has capabilities to improve diagnostics, research and education. In this study, the applicability of CBA methods in dentomaxillofacial radiology is evaluated. Methods: Recent research has discovered numerical features that were successfully applied for an automatic categorization of radiographs. In our experiments, oral and maxillofacial radiographs were obtained from the day-to-day routine of a university hospital and labelled by an experienced dental radiologist regarding the technique and direction of imaging, as well as the displayed anatomy and biosystem. In total, 2000 radiographs of 71 classes with at least 10 samples per class were analysed. A combination of co-occurrence-based texture features and correlation-based similarity measures was used in leaving-one-out experiments for automatic classification. The impact of automatic detection and separation of multi-field images and automatic separability of biosystems were analysed. Results: Automatic categorization yielded error rates of 23.20%, 7.95% and 4.40% with respect to a correct match within the first, fifth and tenth best returns. These figures improved to 23.05%, 7.00%, 4.20%, and 20.05%, 5.65% and 3.25% if automatic decomposition was applied and the classifier was optimized to the dentomaxillofacial imagery, respectively. The dentulous and implant systems were difficult to distinguish. Experiments on non-dental radiographs (10 000 images of 57 classes) yielded 12.6%, 5.6% and 3.6%. Conclusion: Using the same numerical features as in medical radiology, oral and maxillofacial radiographs can be reliably indexed by global texture features for CBA and data mining.
27.	Ekestubbe, Annika, 1953, et al. (författare) Absorbed doses and energy imparted from tomography for dental implant installation. Spiral tomography using the Scanora technique compared with hypocycloidal tomography 1992 Ingår i: Dentomaxillofacial Radiology. - 0250-832X .- 1476-542X. ; 21, s. 65-69 Tidskriftsartikel (refereegranskat)abstract Anne Thilander Klang hetter Anne Thilander som ogift
28.	Ekestubbe, Annika, 1953, et al. (författare) Effective and organ doses from scanography and zonography: a comparison with periapical radiography. 2004 Ingår i: Dento maxillo facial radiology. - : British Institute of Radiology. - 0250-832X. ; 33:2, s. 87-92 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: To compare absorbed and effective doses from scanographic and zonographic examinations performed in the Scanora unit with intraoral periapical radiography. METHODS: Absorbed dose measurements were made on an anthropomorphic phantom head with LiF thermoluminescent dosemeters in the regions of the pituitary gland, eye lenses, parotid glands, submandibular glands, thyroid gland and skin. Energy imparted was calculated from the measurements of air collision kerma and effective doses by using the quotient 24 mSv J-1 between energy imparted and effective dose. The upper and lower third molar region was examined with intraoral radiographs and with ramus scanograms, dental scanograms and dental zonograms. Radiation dose measurements were also performed for Scanora panoramic radiography (jaw and dental). RESULTS: The effective doses for the ramus and dental scanograms were 0.01 mSv, similar or lower than for intraoral radiography. Zonography yielded the highest effective dose (0.03 mSv). Except for the skin doses, the salivary glands received the highest doses. Salivary gland doses were slightly higher from narrow beam than from intraoral radiography. CONCLUSIONS: Detail narrow beam radiography with the Scanora is an alternative to periapical radiography and is preferred, from a radiation dose point of view, over zonography.
29.	Ekestubbe, Annika, 1953, et al. (författare) Quality of digital pre-implant tomography: comparison of film-screen images with storage phosphor images at normal and low dose. 2003 Ingår i: Dento maxillo facial radiology. - 0250-832X. ; 32:5, s. 322-6 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: The aim of this pilot study was to compare the image quality of a storage phosphor system with that of conventional film-screen in pre-implant conventional tomography, and to test the influence of radiation dose on image quality in the storage phosphor system. METHODS: Cross-sectional conventional tomographic images (Scanora) technique) were obtained on 11 patients with film-screen and with storage phosphor image plates (Digora) PCT) at normal and low doses. Ten observers graded the visibility of anatomical structures of importance for implant planning. A three-step rating scale was used, where -1 =worse, 0=equal and 1=better than the reference image. RESULTS: Although image quality was graded as equally good in the majority (59%) of images, the storage phosphor system scored significantly lower than film-screen (-0.37 vs 0.00, respectively) for all the images. Low dose storage phosphor images were rated significantly lower (-0.21) than normal dose images (0.00). CONCLUSIONS: In the majority of patients, anatomic structures of importance for implant planning are visualized equally well on storage phosphor and film-screen images. However, where differences do exist, storage phosphor images score lower than film-screen images. Dose reduction in the storage phosphor system had a negative influence on image quality.
30.	Granström, Gösta, 1950, et al. (författare) Imaging of osseointegrated implants in the temporal bone by accuitomo 3-dimensional cone beam computed tomography. 2011 Ingår i: Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. - 1537-4505. ; 32:2, s. 199-203 Tidskriftsartikel (refereegranskat)abstract Follow-ups of osseointegrated implants in the temporal bone have been limited to clinical stability and resonance frequency measurements. Standard computed tomographic scanning is restricted because of the high radiation doses to the brain and the presence of disturbing metal artifacts. The present study was undertaken to evaluate the use of cone beam computed tomography preoperatively and postoperatively.
31.	Granström, Gösta, 1950, et al. (författare) Sleeping implant in the temporal bone: report of a case with 20-year follow-up. 2012 Ingår i: Clinical implant dentistry and related research. - : Wiley. - 1708-8208 .- 1523-0899. ; 14:2, s. 236-40 Tidskriftsartikel (refereegranskat)abstract Background: There is limited knowledge of the long-term fate of “sleeping” or nonloaded implants in the temporal bone. Purpose: This article describes the fate of a fixture installed in the temporal bone that remained unloaded for 20 years. Patient and Methods: A 25-year-old male with hemifacial microsomia had three osseointegrated implants installed for an auricular episthesis and bone-anchored hearing aid (BAHA) in the left temporal bone in 1988. Two of the implants for the ear episthesis were activated the same year, but the fixture for the hearing aid was not uncovered until 2008. When the patient experienced hearing problems at his office, he wanted to reactivate the sleeping implant. An audiogram showed a maximum conductive hearing loss with good preserved cochlear function. Before reactivation, an Accuitomo three-dimensional, cone beam computed tomography was performed. Resonance frequency analysis (RFA) using the Ostell technique was done when the implant was uncovered. Results: Preoperative x-ray investigation showed the sleeping implant to be well integrated in the temporal bone, covered with 1 mm bone, and with no signs of resorption. Geometric measurements correlating to the two loaded implants showed the sleeping implant to be positioned too close to these to be able to anchor a BAHA without interference with the episthesis. Surgical exploration was done to analyze the implant. The clinical status correlated well to that diagnosed from the x-ray investigation. RFA revealed the implant to be well integrated. A new fixture and abutment for BAHA was installed in the temporal line and activated 2 months after surgery. The patient is today supplied with a BAHA. Conclusion: It seems possible to use sleeping implants in the temporal bone even 20 years after installation.
32.	Gröndahl, Hans-Göran, 1940 (författare) Clinical applications of 3DX Accu-I-Tomo 2007 Ingår i: Thinking about today´s dentistry. Quintesence, TOKYO. ; :2007, s. 146-154 Tidskriftsartikel (refereegranskat)
33.	Hakeberg, Magnus, 1954, et al. (författare) Long-term effects on dental care behavior and dental health after treatments for dental fear. 1993 Ingår i: Anesthesia progress. - 0003-3006 .- 1878-7177. ; 40:3, s. 72-7 Tidskriftsartikel (refereegranskat)abstract Three different treatments for dental fear were tested in a long-term perspective study. Twenty-nine patients with severe dental anxiety and avoidance behavior were assigned to Behavioral Therapy (BT, n = 12), PRemedication with bensodiazepine (PR, n = 8) or dental treatment under General Anesthesia (GA, n = 9). Ten years after initial treatment the patients were reexamined. Changes in dental anxiety and dental care attendance were reported. Patients' dental health status was assessed by radiographic survey. Regular dental attendance was reported by 19 patients (65.5%), with a significantly better result for the BT group (91.6%) compared to the GA group (33.3%). Reported level of dental anxiety, as measured by the Dental Anxiety Scale, revealed a significant reduction during the 10-yr period except among GA patients and those reporting irregular dental attendance behavior. A rise in mood as assessed by the Mood Adjective Checklist was revealed in the total group, with a better effect in the BT and PR groups as well as in patients who reported regular dental attendance. A substantial general improvement in oral health was seen during the 10-yr period, especially among patients receiving regular dental care. Thus, for a majority of patients in this study, directed treatment for dental anxiety and avoidance behavior made it possible to maintain regular dental care behavior during a 10-yr period.
34.	Huumunen, S, et al. (författare) Radiology in endodontic management 2004 Ingår i: Dental outlook. Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
35.	Kamburoğlu, Kivanç, et al. (författare) Effectiveness of limited cone-beam computed tomography in the detection of horizontal root fracture 2009 Ingår i: Dental Traumatology. - : Wiley. - 1600-9657 .- 1600-4469. ; 25:3, s. 256-61 Tidskriftsartikel (refereegranskat)abstract To compare the diagnostic accuracy of conventional film radiography, charge coupled device (CCD) and photostimulable phosphor plate (PSP) digital images and limited cone-beam computed tomography in detecting simulated horizontal root fracture. Root fractures were created in the horizontal plane in 18 teeth by a mechanical force and fragments were relocated. Another 18 intact teeth with no horizontal root fracture served as a control group. Thirty-six teeth were placed in the respective empty maxillary anterior sockets of a human dry skull in groups three by three. Intraoral radiographs were obtained in three different vertical views by utilizing Eastman Kodak E-speed film, CCD sensor, RVG 5.0 Trophy and a PSP sensor Digora, Optime. Cone beam CT images were taken with a unit (3D Accuitomo; J Morita MFG. Corp, Kyoto, Japan). Three dental radiologists separately examined the intraoral film, PSP, CCD and cone beam CT images for the presence of horizontal root fracture. Specificity and sensitivity for each radiographic technique were calculated. Kappa statistics was used for assessing the agreement between observers. Chi-square statistics was used to determine whether there were differences between the systems. Results were considered significant at P < 0.05. Cone beam CT images revealed significantly higher sensitivities (P < 0.05) than the intraoral systems between which no significant differences were found. Specificities did not show any statistically significant differences between any of the four systems. The kappa values for inter-observer agreement between observers (four pairs) ranged between 0.82–0.90 for the 3DX evaluations and between 0.63–0.71 for the different types of intraoral images. Limited cone beam CT, outperformed the two-dimensional intraoral, conventional as well as digital, radiographic methods in detecting simulated horizontal root fracture.
36.	Molander, Björn, 1949, et al. (författare) Quality of film-based and digital panoramic radiography. 2004 Ingår i: Dento maxillo facial radiology. - : British Institute of Radiology. - 0250-832X. ; 33:1, s. 32-6 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: To compare the image quality of panoramic radiographs obtained with storage phosphor plate and screen-film systems. METHODS: Panoramic radiographs were taken in 60 patients both with film and with a storage phosphor plate system (30 with DenOptix (Dentsply/Gendex) and 30 with Digora PCT). The images were obtained with either the Cranex Tome or the Scanora multimodal X-ray unit. The screen-film combination was Lanex medium/Curix Ortho HT-G. The digital images were displayed as 8-bit images with a 300 dpi resolution on a 19" monitor and the film images were placed on a light box adjacent to the screen. Ten observers evaluated diagnostic image quality by means of visual grading analysis of different anatomical structures. The structures were scored as being visualized much better (5), better (4), equal (3), worse (2) or much worse (1) in the digital images than in the film images. The mean number of patients receiving the different scores was calculated. Statistical methods used were Wilcoxon sign rank test and Mann-Whitney test. RESULTS: On average, visualization was equal in 19 of the 30 patients imaged using Digora PCT; in 10 it was worse. The corresponding values for DenOptix were 20 and 9. The difference between the film-based and the digital images was small but statistically significant (P<0.0001). The difference between the two image plate systems was not statistically significant (P>/=0.17). CONCLUSIONS: It was concluded that digital panoramic radiographs are equivalent to film-based images for most purposes.
37.	Petersson, Arne, et al. (författare) Datortomografi inom odontologisk radiologi 2009 Ingår i: Tandläkartidningen. - 0039-6982. ; 101:2, s. 42-50 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Datortomografi används ofta vid odontologiska röntgenundersökningar. Konventionell datortomografi introducerades år 1972 och nu finns datortomografer vid alla medicinska röntgenavdelningar. Digital volymtomografi är en typ av datortomografi som sedan slutet av 1990-talet kommit till stor användning vid odontologiska undersökningar. Konventionell datortomografi ger höga stråldoser men med volymtomografi kan stråldosen reduceras väsentligt. Konventionell datortomografi används vid utredning av ansiktstraumata och tumörer medan volymtomografi vanligen används vid undersökning av tänder och käkar.
38.	Redfors, Ylva Dahlin, et al. (författare) Otosclerosis : anatomy and pathology in the temporal bone assessed by multi-slice and cone-beam CT 2012 Ingår i: Otology and Neurotology. - Philadelphia, USA : Lippincott Williams & Wilkins. - 1531-7129 .- 1537-4505. ; 33:6, s. 922-927 Tidskriftsartikel (refereegranskat)abstract Objective: To assess the use of cone beam computed tomography (CBCT) compared with multi-slice computed tomography (MSCT) in otosclerosis, with special emphasis on middle-and inner-ear anatomy.Study Design: Prospective study.Patients: Twenty patients who underwent a stapedectomy 30 years ago were selected on the basis of bone conduction threshold values. Their mean age was 65 years (range, 48-76 yr).Intervention: All patients underwent CBCT and MSCT with a slice thickness of 0.5 to 0.6 mm.Main Outcome Measures: Sixteen middle-and inner-ear anatomic structures and stapedial prostheses were analyzed by visual grading analysis. To assess critical reproduction and thereby the clinical applicability of CBCT, a dichotomization was made. Assessment of otosclerotic foci was performed using a grading system dividing the lesions in; 1) sole fenestral lesions, 2) retrofenestral lesions with or without fenestral lesions and 3) severe retrofenestral lesions.Results: The 16 anatomic structures were clearly reproduced by both imaging techniques. However, there was an interobserver variation in judging the superiority of 1 method in favor of the other. Otosclerotic lesions were diagnosed in 80/95% using MSCT and 50/85% using CBCT (evaluators 1 and 2, respectively). Retrofenestral lesions were diagnosed in 5 of 10 of ears with severe-to-profound hearing loss, whereas no retrofenestral lesions were diagnosed in the 10 ears with mild-to-moderate hearing loss. The stapedial prostheses were adequately or very well reproduced by both methods.Conclusion: CBCT is a new imaging technique with a considerably lower radiation dose than conventional MSCT. Our study indicates that CBCT is suitable and, in many ways, equivalent to MSCT, for temporal bone imaging in otosclerosis.
39.	Sener, E., et al. (författare) Accuracy of Proximal Caries Depth Measurements: Comparison of Two Computed Cone Beam Tomography and Storage Phosphor Plate Systems 2017 Ingår i: Meandros Medical and Dental Journal. - : Galenos Yayinevi. - 2149-9063. ; 18:2, s. 108-114 Tidskriftsartikel (refereegranskat)abstract Objective: The aim of this study was to compare the accuracy of NewTom 9000 [cone beam computerized tomography (CBCT)], Accu-I-Tomo [limited CBTC (LCBCT)] and Digora Optime [storage phosphor plate (SPP)] imaging systems in assessing the depths of defects with different shapes and sizes on the proximal surfaces of teeth. Materials and Methods: Thirty out of 50 incisive teeth with sound proximal surfaces were divided into three equal groups. Mechanical defects of different sizes and depths were created on their proximal surfaces and teeth were placed in acrylic blocks with approximal contacts. Radiographs of the blocks were obtained with CBCT, LCBCT and SPP systems. The depth measurements of 60 artificial defects were performed by 3 radiologists in the digital radiographs. The gold standard (true measure) was defined as the mean of the 2 observers' measurements on the microscopic sections. Results from imaging systems and true depths were compared using Bland-Altman plots. The agreement was determined with intra-class correlation coefficient. Results: Maximum deviation from the true length in axial and sagittal slices of CBCT system was 2 mm [95% confidence interval (CI) 2.60-0.60] and 1.5 mm (95% CI 0.30-2.30) respectively while the deviation of LCBCT was 0.66 mm (95% CI 0.53-2.22) and 0.37 mm (95% CI 0.50-2.25). The deviation from truth for SPP was 0.66 mm (95% CI 0.33-2.25). Correlation among observers was 0.487 and 0.700 respectively, for CBCT axial and sagittal slices; while it was 0.979 and 0.985 for LCBCT and 0.979 for SPP. Conclusion: Images obtained with the Accu-I-Tomo LCBCT system were more accurate than Newtom CBCT and Digora SPP system for measurement of caries lesion depth. Correlation among observers was higher for LCBCT and SPP systems compared with CBCT system.
40.	Sogur, E, et al. (författare) Detectability of chemically induced periapical lesions by limited cone beam computed tomography, intra-oral digital and conventional film radiography 2009 Ingår i: Dentomaxillofacial Radiology. - 0250-832X. ; 38:7, s. 458-64 Tidskriftsartikel (refereegranskat)abstract Objective: Our aim was to compare the Accu-I-Tomo (3DX), the Digora® Optime image plate system and F-speed film in detecting chemically created apical lesions. Methods: Lesions were created by applying perchloric acid apical to extracted teeth in jaw specimens for 1, 1.5 or 2 h. After being repositioned, teeth were radiographed with Accu-I-Tomo limited cone beam CT (LCBCT), Digora® Optime storage phosphor plates (SPP) and F-speed films. Six observers scored the presence of lesions using a five-grade scale. The accuracy of each observer and modality was assessed through receiver operating characteristic (ROC) analysis and Az values were compared using two-way ANOVA. Pairwise comparisons of imaging systems were carried out using the Mann–Whitney U-test. Differences in Az values were compared using Friedman and Dunn's tests. Kappa ({kappa}) was used to measure interobserver agreement. Results: The Az values were larger for LCBCT than for SPP and film for all acid durations. For 1 h of acid duration a significant difference was found between LCBCT and film (P = 0.02) and between LCBCT and SPP (P = 0.0043), For 1.5 h a significant difference (P = 0.006) was found between LCBCT and SPP only. For 2 h acid duration, there was no significant difference between LCBCT and film or SPP (P>0.05). Between SPP and film no significant difference was found for any acid duration (P>0.05). {kappa} ranged between fair and moderate for LCBCT and between slight and fair for SPP and film. Conclusion: LCBCT images provided better than or similar detectability as film and SPP images of chemically created periapical lesions.
41.	Sogur, E, et al. (författare) Imaging of root canal fillings: a comparison of subjective image quality between limited cone-beam CT, storage phosphor and film radiography 2007 Ingår i: Int Endod J. ; 40:3, s. 179-185 Tidskriftsartikel (refereegranskat)abstract Aim To compare the subjective quality of limited cone-beam computed tomography (LCBCT), storage phosphor plate (SPP) and F-speed film images for the evaluation of length and homogeneity of root fillings. Methodology Root canals of 17 extracted permanent mandibular incisor teeth were filled. With the teeth placed in their jaws, images were obtained with Accu-I-Tomo LCBCT, Digora® Optime image plate system and F-speed film using exposure parameters yielding ‘clinically’ acceptable density and contrast. Three radiologists and three endodontists independently rated the quality of all images in respect to homogeneity and the length of root fillings using a 3-graded scale. Evaluations were undertaken in two sessions. In the first, the coronal LCBCT images were not included. In the second, both coronal and sagittal LCBCT images were rated along with F-speed film and SPP images. Results were compared using the Friedman test (P < 0.05). Pair-wise comparisons of systems were completed using the Wilxocon signed-ranks test (P < 0.05). Kappa was used to measure interobserver agreement. Results Digora images were rated superior, consecutively followed by F-speed films and LCBCT images, for the evaluation of both homogeneity and length of root fillings in both the evaluation sessions (P < 0.05). Kappa ranged from slight to moderate for the length evaluation of root fillings and from poor to fair for the evaluation of homogeneity of root fillings. Conclusion Image quality of storage phosphor images was subjectively as good as conventional film images and superior to LCBCT images for the evaluation of both homogeneity and length of root fillings in single-rooted teeth.
42.	Soǧur, Elif, et al. (författare) Does a combination of two radiographs increase accuracy in detecting acid-induced periapical lesions and does it approach the accuracy of cone-beam computed tomography scanning? 2012 Ingår i: Journal of Endodontics. - : Elsevier BV. - 0099-2399. ; 38, s. 131-136 Tidskriftsartikel (refereegranskat)abstract Introduction: The purpose of this study was to determine whether the use of a combination of 2 images (storage phosphor plates [SPPs] and F-speed films [Eastman Kodak, Rochester, NY]) with a 10° difference in horizontal beam angulation resulted in better detectability of chemically created periapical defects than when only 1 image was used and whether a detectability as good as that achieved by limited cone-beam computed tomography (LCBCT) scanning could be achieved. Methods: Lesions were created by 1, 1.5, and 2 hours of acid application apical to extracted teeth in jaw specimens. After repositioning, teeth were radiographed with Accu-I-Tomo LCBCT, Digora Optime SPP system, and F-speed films. The SPPs and films were exposed at 0° and 10° horizontal angulations. The diagnostic accuracy (Az) was compared using 2-way analysis of variance; pair-wise comparisons were performed using the post hoc t test. Kappa was used to measure interobserver agreement. Results: A combination of 2 exposures with a 10° difference in horizontal angulation caused an increase, although not statistically significant, in the accuracy of both films and SPPs for all acid durations (P >.05) compared with when only 1 exposure was used. The accuracy did not approach that of LCBCT. Conclusions: Using a combination of 2 exposures instead of 1 did not significantly increase the accuracy in detecting acid-induced lesions at the apices of single-rooted premolars. The accuracy of LCBCT was superior. Copyright © 2012 American Association of Endodontists.
43.	The osseointegration book. From Calvarium to calcaneus 2005 Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)

Skapa referenser, mejla, bekava och länka

Länka till träfflistan

Träfflista för sökning "WFRF:(Gröndahl Hans Göran 1940) "

Avgränsa träffmängd

År