SEDENTEXCT: Guidelines and evidence-based use of CBCT

Transcription

1 : Guidelines and evidence-based use of CBCT Keith Horner

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3 John Dalton Rutherford Bragg UK largest single-site University 34,000 students

4 University Dental Hospital of Manchester 90,000 patients attend for treatment every year

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6 CBCT service For our own hospitals For other hospitals in the region For private dentists (mainly implant dentists)

7 Cone Beam Computed Tomography (CBCT)

8 30+ CBCT systems marketed worldwide

9 Radiation dose implications

10 : the background In 2006/7: New technology (CBCT) Evidence that CBCT gave higher doses of radiation to patients Little evidence of the diagnostic value and limitations of CBCT Challenges for dentists and medical physics experts wanting to install CBCT No guidelines anywhere on good practice

11 : the background

12 : the background In 2007: European consortium of Universities A manufacturer of medical X- ray test objects

13 Safety and Efficacy of a New and Emerging Dental X-ray Modality 1. To develop evidence-based guidelines on the use of CBCT in dentistry, covering referral criteria, quality assurance and other optimisation strategies.

14 Safety and Efficacy of a New and Emerging Dental X-ray Modality 2. To determine patient dose in CBCT, with an emphasis on paediatric dosimetry, and personnel dose.

15 Safety and Efficacy of a New and Emerging Dental X-ray Modality 3. To perform diagnostic accuracy studies for CBCT in key clinical applications in dentistry.

16 Safety and Efficacy of a New and Emerging Dental X-ray Modality 4. To develop a quality assurance (QA) programme, including the development of a tool/tools for QA and to define exposure protocols.

17 Safety and Efficacy of a New and Emerging Dental X-ray Modality 5. To make an economic evaluation ( cost effectiveness assessment) of CBCT compared with traditional methods of dental imaging.

18 Safety and Efficacy of a New and Emerging Dental X-ray Modality 6. To conduct valorisation, both dissemination and training, activities via an open access website.

19 Safety and Efficacy of a New and Emerging Dental X-ray Modality Evidence-based guidelines on the use of CBCT in dentistry, covering referral criteria, quality assurance and other optimisation strategies. Systematic review of the evidence

20 What are clinical guidelines? systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances Field, MJ, Lohr, KN, (eds). Guidelines for clinical practice: from development to use. National Academy Press, Washington D.C., 1992.

21 CBCT is not indicated as a method of caries detection and diagnosis B CBCT equipment should be installed in a protected enclosure and the whole of the enclosure designated a Controlled Area D CBCT is not normally indicated for planning the placement of temporary anchorage devices in orthodontics GP

22 Grade A At least one meta analysis, systematic review, or RCT rated as 1++, and directly applicable to the target population; or a systematic review of RCTs or a body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results B A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or extrapolated evidence from studies rated as 1++ or 1+ C A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or extrapolated evidence from studies rated as 2++ D Evidence level 3 or 4; or extrapolated evidence from studies rated as 2+ GP Good Practice (based on clinical expertise of the guideline group and Consensus of stakeholders) Scottish Intercollegiate Guidelines Network (SIGN), 2008

23 Lecture outline: First part: Justification and referral criteria How strong is the evidence for using CBCT for specific clinical applications? referral criteria Second part: Radiation dose, dose limitation and quality assurance for CBCT Highlight the clinical relevance guidelines

24 Justification and referral criteria To scan, or not to scan, that is the question...

25 Radiation Protection principles International Commission on Radiological Protection (ICRP) Three fundamental principles of radiological protection: justification optimisation [the application of dose limits] The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP Vol 37 (2007)

26 Radiation Protection principles Justification The process of determining whether a planned activity involving radiation is, overall, beneficial, i.e. whether the benefits to individuals and to society from introducing or continuing the activity outweigh the harm (including radiation detriment) resulting from the activity The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP Vol 37 (2007)

27 Radiation Protection principles Justification...should do more good than harm The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP Vol 37 (2007)

28 What are radiological referral criteria? Referral criteria are NOT:...a rigid constraint on clinical practice, but a concept of good practice against which the needs of the individual patient can be considered Good practice Individual prescription of X- ray based imaging

29 3-dimensions versus 2-dimensions

30 The trade off High resolution - 2D Lower resolution - 3D

31 Not all CBCT machines are the same! Liang X et al. (2010) A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT): Part I. On subjective image quality. Eur J Radiol 75:

32 What do dentists do? Dental caries (decay) Extract teeth Periodontal disease Fill gaps in the dentition Pulpal disease and root canal treatments Tooth trauma Orthodontic treatments Aesthetic treatments

33 Caries detection Bitewing radiography: Proximal caries: Mean sensitivity 50% Mean specificity 87% Occlusal caries: Mean sensitivity 39% Mean specificity 91% Bader JD et al Systematic reviews of selected dental caries diagnostic and management methods. J Dent Educ :

34 Caries detection

35 Caries detection: CBCT In 5 out of 7 research studies on proximal caries: no significant differences between CBCT and bitewing radiography In 2 studies there was higher sensitivity for CBCT

36 Caries detection: CBCT In all 3 research studies on occlusal caries: CBCT had higher sensitivity than bitewing radiography But there may be loss of specificity (more false positive results).

37 The artefact problem

38 Caries detection: CBCT CBCT is not indicated as a method of caries detection and diagnosis B

39 Periodontal diagnosis Primary diagnostic method is clinical examination Limited research on CBCT

40 Periodontal diagnosis CBCT may be more accurate for detection and quantification of inter-radicular bone defects/ furcation lesions May be useful in evaluating the response to surgery and regenerative treatment of intra-bony defects.

41 Periodontal diagnosis CBCT is not indicated as a routine method of imaging periodontal bone support C Limited volume, high resolution CBCT may be indicated in selected cases of infra-bony defects and furcation lesions, where clinical and conventional radiographic examinations do not provide the information needed for management C

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43 Periapical diagnosis CBCT Properly validated in vivo studies impossible Laboratory and animal studies possible and suggest improved sensitivity of CBCT Simple comparative clinical studies Conventional 34% of lesions were missed by periapical radiography (Low et al 2008)

44 Periapical diagnosis CBCT is not indicated as a standard method for identification of periapical pathosis GP Limited volume, high resolution CBCT may be indicated for periapical assessment, in selected cases, when conventional radiographs give a negative finding when there are contradictory positive clinical signs and symptoms GP

45 Endodontics CBCT identifies more root canals than conventional radiography All posterior teeth Requires high resolution CBCT:? 0.12 mm resolution (or better)

46 Endodontics CBCT is not indicated as a standard method for demonstration of root canal anatomy GP CBCT Limited volume, high resolution CBCT may be indicated,for selected cases, where intraoral radiographs provide information on root canal anatomy which is equivocal or inadequate for planning treatment, most probably in multi-rooted teeth GP Conventional

47 Complex endodontic cases Perio-endo lesions

48 Complex endodontic cases Perio-endo lesions Re-treatment cases

49 Complex endodontic cases Perio-endo lesions Re-treatment cases Resorption cases

50 Complex endodontic cases Perio-endo lesions Re-treatment cases Resorption cases

51 Complex endodontic cases Limited volume, high resolution CBCT may be justifiable for selected cases, where endodontic treatment is complicated by concurrent factors, such as resorption lesions, combined periodontal/endodontic lesions, perforations and atypical pulp anatomy C

52 Implantology Main driver for development of CBCT Conventional (medical) CT has been the main method Usually radiation dose advantage of CBCT

53 Implantology Special indications for cross-sectional imaging (adapted from Fig. 2b in Harris et al 2002 E.A.O. Guidelines for the use of diagnostic imaging in implant dentistry. Clin Oral Implants Res 2002; 13: ). Maxilla Single tooth Mandible Single tooth a. incisive canal b. descent of maxillary sinus c. clinical doubt about shape of alveolar ridge a. descent of maxillary sinus b. clinical doubt about shape of alveolar ridge Partially dentate Edentulous a. descent of maxillary sinus b. clinical doubt about shape of alveolar ridge a. clinical doubt about position of mandibular canal b. clinical doubt about shape of alveolar ridge Partially dentate a. clinical doubt about position of mandibular canal or mental foramen b. clinical doubt about shape of alveolar ridge Edentulous a. severe resorption b. clinical doubt about shape of alveolar ridge c. clinical doubt about position of mandibular canal if posterior implants are to be placed

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55 Bone quality assessment Cortical thinning Cortical porosity Sparse trabeculation Difficulty in visualising neurovascular canals

56 Implantology CBCT is indicated for crosssectional imaging prior to implant placement as an alternative to existing cross-sectional techniques where the radiation dose of CBCT is shown to be lower D

57 Implantology For cross-sectional imaging prior to implant placement, the advantage of CBCT with adjustable fields of view, compared with multislice CT, becomes greater where the region of interest is a localised part of the jaws, as a similar sized field of view can be used GP

58 Implant review

59 Localising unerupted and impacted teeth Numerous case reports and nonsystematic reviews on CBCT use for 3 rd molar assessment Focus on lower third molar and ID canal relationship Cone-beam CT revealed the number of roots of teeth more reliably than panoramic radiographs. Suomalainen et al 2010 Dentomaxillofacial Radiology,109:

60 Third molars Conflicting evidence on whether CBCT is more accurate in predicting neurovascular bundle exposure during extraction of impacted mandibular third molar teeth.

61 Panoramic Panoramic CBCT reformat

62 Third molars Where conventional radiographs suggest a direct inter-relationship between a mandibular third molar and the mandibular canal, and when a decision to perform surgical removal has been made, CBCT may be indicated C

63 Third molars Factors associated with post-operative dysaesthesia Darkening of the root Interruption of the canal wall Diversion of the canal (Rood & Shehab, 1990)

64 Other teeth: maxillary canines

65 Detection of root resorption In vitro studies of diagnostic accuracy Table IV. Sensitivity and specificity of resorption detection for the 3 radiologic imaging methods, expressed as percentages Panoramic CBCT Accuitomo CBCT Scanora Sensitivity Specificity False-positive errors False-negative errors Alqerban A, Jacobs R, Souza PC, Willems G. Am J Orthod Dentofacial Orthop Dec;136(6):764.e1-11 Improved diagnostic accuracy of CBCT shown in other studies in endodontic literature

66 Detection of root resorption In vivo studies 27 patients 39 ectopic canines CBCT Conventional (pan, ceph, intraorals) 8 observers 82.7% agreement in resorption assessment Botticelli S et al., Eur J Orthod 2011, 33:

67 Effect on treatment plans Botticelli et al., 2011 Change in treatment plan in 29.5% of cases Botticelli S et al., Eur J Orthod 2011, 33:

68 CBCT may be indicated for the localised assessment of an impacted tooth (including consideration of resorption of an adjacent tooth) where the current imaging method of choice is conventional dental radiography and when the information cannot be obtained adequately by lower dose conventional (traditional) radiography C

69 General orthodontic assessment

70 CBCT in Orthodontics: the hype NO MORE DENTAL IMPRESSIONS!.builds 2D lateral and PA cephalograms a necessity for the orthodontist One 24 sec scan of an orthodontic patient yields a 3D image of the head and neck! We have to embrace [CBCT] and incorporate it into our everyday Less exposure than the old way of gathering diagnostic data on our patients treatment planning We have eliminated dental impressions in our practice The information provided by CBCT...is more comprehensive and much more accurate (diagnostic truth)

71 New York Times 22 November 2010

72 Orthodontic Specialists

73 Generalised (full dentition face/head) application Higher radiation dose What is the benefit? It is not appropriate to take a CBCT examination solely to reconstruct a panoramic or cephalometric view if a lower dose radiography technique would provide adequate diagnostic information Health Protection Agency: The Radiation Protection Implications of the Use of Cone Beam Computed Tomography (CBCT) in Dentistry - What You Need to Know. Chenin DL. 3D cephalometrics: the new norm. Alpha Omegan Jun;103(2):51-6.

74 Generalised (full dentition/face/head) application Technology exists to image and analyse tooth and jaw positions accurately in 3 dimensions 3D cephalometry Chenin DL. 3D cephalometrics: the new norm. Alpha Omegan Jun;103(2):51-6.

75 Generalised (full dentition/face/head) application More accurate assessment of root angulations compared with panoramic radiographs Pan Van Elslande et al (2010) Am J Orthod Dentofacial Orthop 137(4 Suppl):S94-9. Bouwens et al (2011) Am J Orthod Dentofacial Orthop 139, CBCT Pan

76 Generalised (full dentition/face/head) application Replacing alginate impressions Custom fabrication of brackets and wires (e.g. Insignia process; Ormco Corp. California) Invisalign multiple scans needed?

77 Routine orthodontic imaging...much of the literature on using large volume CBCT for routine orthodontic diagnosis and treatment was anecdotal, case report and opinion-based, with a lack of evidence of significant clinical impact Radiation Protection: Cone Beam CT for Dental and Maxillofacial Radiology (2011). Images from Anatomage Inc. Orthodontics.html

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79 Large volume CBCT should not be used routinely for orthodontic diagnosis GP For complex cases of skeletal abnormality, particularly those requiring combined orthodontic/surgical management, large volume CBCT may be justified in planning the definitive procedure, particularly where multislice CT is the current imaging method of choice GP

80 In 2010, the House of Delegates of the American Association of Orthodontists adopted a resolution that states: RESOLVED, that the AAO recognizes that while there may be clinical situations where a cone-beam computed tomography (CBCT) radiograph may be of value, the use of such technology is not routinely required for orthodontic radiography

81 Anomalies of teeth Dilacerations

82 Anomalies of teeth Gemination But does this make any difference to management...?

83 Trauma

84 Shintaku et al. Dent Traumatol. 2009; 25: Drage & Sivarajasingam 2009; Br J Oral Maxillofac Surg;47: For maxillofacial fracture assessment, where crosssectional imaging is judged to be necessary, CBCT may be used as an alternative imaging modality to conventional CT where radiation dose is shown to be lower and soft tissue detail is not required D

85 Dento-alveolar trauma CBCT offers increased accuracy in detection of horizontal and vertical root fractures (Hassan et al, 2009; Kamburoğlu et al, 2009) High resolution CBCT important (Kamburoğlu et al, 2010) Diagnostic advantage seen at 0.2mm voxels (or better) but lost at 0.3mm voxels (Melo et al, 2010)

86 Dento-alveolar trauma Artefact from posts and root fillings may complicate diagnostic tasks

87 Dento-alveolar trauma Limited volume, high resolution CBCT is indicated in the assessment of dental trauma (suspected root fracture) in selected cases, where conventional intraoral radiographs provide inadequate information for treatment planning B

88 Cysts and other benign bone pathosis Array of case reports of using CBCT for assessment of bony diseases No significant research studies

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91 TMJ Where the existing imaging modality for examination of the TMJ is conventional CT, CBCT is indicated as an alternative where radiation dose is shown to be lower B

92 Incidental findings

93 Incidental findings

94 Final points: justification and referral criteria Available on website at To be published as an official European Commission document in their Radiation Protection series

95 Final points: justification and referral criteria CBCT should only be used when the question for which imaging is required cannot be answered adequately by lower dose conventional (traditional) radiography Is it likely to make any difference to my treatment plan? Basic Principles for Use of Dental Cone Beam CT: Consensus Guidelines of the European Academy of Dental and Maxillofacial Radiology. Dentomaxillofac Radiol 2009; 38:

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97 Acknowledgement: The research leading to these results has received funding from the European Atomic Energy Community s Seventh Framework programme FP7/ under grant agreement no (: Safety and Efficacy of a New and Emerging Dental X-ray Modality).