Cone Beam Computed Tomography.

In the last several decades, the need for 3D images in dentistry have developed. Computerized tomography was first introduced mainly with the advent of implantology, but its use remained limited to a small number of specialists, due to its indications, access and dose radiation. In the late 90's, a new technology using a cone-shaped beam and a reciprocating detector, which rotates around the patient 360 degrees and acquires projected data in a single rotation, namely the cone beam computerized tomography (CBCT), invaded dentistry, making the perception of 3D easily acceptable to dentists and their patients.

Reducing an already low dental diagnostic X-ray dose: does it make sense? Comparison of three cost-utility analysis methods used to assess two dental dose-reduction measures.

OBJECTIVES: To find a method that is suitable for providing an objective assessment of the cost effectiveness of a dose-reducing measure used for diagnostic dental X-ray exposures. METHODS: Three cost-utility analysis (CUA) methods were evaluated by comparing their assessments of two dose-reduction measures, a rectangular collimator and the combination of two devices that reduce the radiation dose received during orthodontic lateral cephalography. The following CUA methods were used: (1) the alpha value (AV), a monetary valuation of dose reduction used in the nuclear industry; (2) the value of a statistical life for valuation of the reduction in stochastic adverse effects; and (3) the time-for-time method, based on the postulate that risk reduction is effective when the number of years of life gained is more than the years that an average worker must work to earn the costs of the risk-reducing measure. The CUA methods were used to determine the minimum number of uses that was required for the dose-reducing device to be cost effective. The methods were assessed for coherence (are comparable results achieved for comparable countries?) and adaptability (can the method be adjusted for age and gender of specific patient groups?). RESULTS: The performance of the time-for-time method was superior to the other methods. Both types of dose-reduction devices tested were assessed as cost effective after a realistic number of uses with all three methods except low AVs. CONCLUSIONS: CUA for the methods of X-ray dose reduction can be performed to determine if investment in low dose reduction is cost effective. The time-for-time method proved to be a coherent and versatile method for performing CUA.

Variation in costs of cone beam CT examinations among healthcare systems.

OBJECTIVES: To analyse the costs of cone beam CT (CBCT) in different healthcare systems for patients with different clinical conditions. METHODS: Costs were calculated for CBCT performed in Cluj (Romania), Leuven (Belgium), Malmö (Sweden) and Vilnius (Lithuania) on patients with (i) a maxillary canine with eruption disturbance, (ii) an area with tooth loss prior to implant treatment or (iii) a lower wisdom tooth planned for removal. The costs were calculated using an approach based on the identification, measurement and valuation of all resources used in the delivery of the service that combined direct costs (capital equipment, accommodation, labour) with indirect costs (patients' and accompanying persons' time, "out of pocket" costs for examination fee and visits). RESULTS: The estimates for direct and indirect costs varied among the healthcare systems, being highest in Malmö and lowest in Leuven. Variation in direct costs was mainly owing to different capital costs for the CBCT equipment arising from differences in purchase prices (range €148 000-227 000). Variation in indirect costs were mainly owing to examination fees (range €0-102.02). CONCLUSIONS: Cost analysis provides an important input for economic evaluations of diagnostic methods in different healthcare systems and for planning of service delivery. Additionally, it enables decision-makers to separate variations in costs between systems into those due to external influences and those due to policy decisions. A cost evaluation of a dental radiographic method cannot be generalized from one healthcare system to another, but must take into account these specific circumstances.

A framework for costing diagnostic methods in oral health care: an application comparing a new imaging technology with the conventional approach for maxillary canines with eruption disturbances.

OBJECTIVES: The aims were (i) to propose a framework for costing diagnostic methods in oral health care and (ii) to illustrate the application of the framework to the radiographic examination of maxillary canines with eruption disturbances. METHODS: The framework for costing, following Drummond et al. (2005), includes three elements: (i) identification of different resources used in producing and delivering the service, (ii) measurement of the amount of each resource required and (iii) valuation of the resources in monetary terms. Four data collection instruments were designed - a protocol for apportioning the cost of capital equipment to each diagnostic procedure, separate forms for recording consumable items, for the time of different health care providers used for a diagnostic examination and a patient survey for calculation of the total cost to the patient associated with the examination. The framework was applied to the radiographic examination of maxillary canines with eruption disturbances comparing two imaging methods: (i) a new method with cone beam computed tomography and panoramic radiography and (ii) a conventional method using intraoral and panoramic radiography. The primary analysis was performed from the perspective of the health care system. A separate analysis included patient costs with health care system costs to provide a societal perspective. Comparison of the two perspectives allows consideration of whether any costs savings to the health care system are generated at the expense of greater costs for patients and their families. Data for the cost-analysis were retrieved from 47 patients (mean age 14 years) referred to a department of radiology for examination of maxillary canines. RESULTS: Application of the framework for costing allowed us to compare the resources used to perform examinations of the two methods. The mean total cost per examination for the new method was 128.38€ and 81.80€ for the conventional method, resulting in an incremental cost per examination of the new method of 46.58€. CONCLUSIONS: The application of the framework demonstrates the feasibility of measuring and comparing the total costs as well as the distribution of total costs between providers and patients for different approaches to this common examination.

The role of the dental surgeon in detecting osteoporosis: the OSTEODENT study.

OBJECTIVE: To determine if thinning (<3 mm width) of the lower cortical border of the mandible on dental panoramic radiographs, as well as other clinical risk factors, may provide a useful diagnostic test for osteoporosis in young postmenopausal women. DESIGN: Six hundred and fifty-two subjects (age range 45-70 years) were involved in this multi-centre, cross-sectional study. SETTING: Patients were recruited from centres in Leuven (Belgium), Athens (Greece), Manchester (UK), and Malmo (Sweden). SUBJECTS AND METHODS: The subject's age, body weight, whether the patient took hormone replacement therapy or had a history of low trauma fracture were used to form a clinical osteoporosis risk assessment (the OSteoporosis Index of RISk or OSIRIS index). Each patient also received a dental panoramic radiographic examination. RESULTS: One hundred and forty subjects had osteoporosis involving at least one of the measurement sites (lumbar spine, femoral neck or total hip). Those with osteoporosis tended to have a low OSIRIS score and a thinned cortical mandibular border. The area under the ROC curve for using both cortical width and OSIRIS to predict osteoporosis was 0.90 (95% CI = 0.87 to 0.92). There was a significant improvement in the diagnostic ability of the combined OSIRIS and cortical width test over both tests applied separately (p <0.001). The cost effectiveness of the cortical width and OSIRIS model was improved by using a high specificity threshold rather than high sensitivity. However, this analysis ignores the costs associated with missed cases of osteoporosis. CONCLUSION: Dentists have a role to play in the detection and referral of patients at high risk of osteoporosis.

Diagnostic and restorative behaviour in Dutch dentists' paediatric dental care.

AIM: This was to assess if Dutch dentists have comparable attitudes in providing diagnosis and consecutive dental treatment in children. Prevention, radiographic diagnostics and restorative care were compared in four consecutive age groups [<6 years old, 6-8, 9-11, 12-17]. METHODS: In a cross-sectional study calculations were made using the financial records of one of the largest Dutch health insurance companies. After Medical Ethics approval all dental records of 4,500 dentists over a period of three consecutive years were used to calculate correlations and odds ratios, using early treatment, oral diagnosis, preventive approach and the use of local analgesia as basic independent variables. RESULTS: Early diagnosis based on the use of radiographs in children younger than 6 years increased the likelihood of direct restorative care 2.8 times and the likelihood of restorative care in future age groups 2.2, 2.0 and 1.6 times respectively. Early radiographs increased the likelihood of diagnostics in consecutive older groups by 3.7, 3.4 and 1.9 times respectively. CONCLUSION: An early diagnostic approach based on radiographs in paediatric dental care seems to be indicative for dentists' pattern of dealing with older children. This child-centred approach is limited to a small number of dentists.

Socio-economic burden of permanent incisor replantation on children and parents.

This study describes the socio-economic burden and attitudes of children and their parents following replantation of avulsed incisors. Records of 80 patients with 99 avulsion injuries treated in a teaching hospital clinic from 1988 to 1999 were reviewed. Mean age at time of injury was 10.6 years (range = 6.6-17.7 years). Complete records for a minimum of 1 year were obtained for 43 patients with 60 replanted incisors. Mean treatment procedures provided during the first year included 5.5 diagnostic periapical radiographs, 1.9 occlusal radiographs, 1.3 pulpectomies, and 2.7 pulp medicament applications. The mean estimated treatment cost and direct time (dentist) for first-year post-trauma management was 1465 dollars CAD and 7.2 h, respectively. Treatment costs were significantly higher during the first year post-trauma for patients who had their incisors extracted (P = 0.04), but there was no significant difference in direct treatment time between the two groups (P = 0.19). Twenty-one patient-parent pairs were surveyed for a number of qualitative factors. Ninety per cent of patients and 86% of parents reported that school and work time was lost. Even after having gone through the painful experience of replantation, the demands of recall, and in some cases, extraction, the majority of patients (67%) and parents (81%) stated that they would have still made the same (replantation) decision. Patient and parent responses were not statistically different (P = 0.453). Almost half the parents stated they would be willing to pay over 2000 dollars CAD to save an incisor. Patients rated retention of an incisor as significantly more important than infraocclusion. This is the first study to quantify the treatment burden of replantation of avulsion injuries exclusively in the pediatric population. This study describes the socio-economic burden and responsibilities of patient/parent and dentist and their role in informed consent.

A survey of radiographic prescription in dental implant assessment.

OBJECTIVES: To survey the current radiographic prescriptions in dental implant assessment amongst dentists in Brazil. METHODS: Sixty-nine dentists were interviewed during a dental implant meeting by two calibrated graduate students, using a 19-question questionnaire, considering imaging modality options both for pre-operative implant site assessment and for follow-up, particularly with respect to cost, patient radiation dose, and broad coverage of facial bones and teeth. Epi-Info 6.04 software was used to analyse the database file. RESULTS: Approximately 63.8% of the dentists prescribed only panoramic radiography for dental implant assessment and 28.9% ordered panoramic radiography plus periapical radiography and/or conventional tomography and/or computed tomography (CT). Only 7.2% of the dentists ordered conventional tomography or CT as a single examination, although 10.1% ordered it in combination with other imaging modalities. The main reasons given for prescribing panoramic radiography were broad coverage and cost (86.4%). CONCLUSIONS: This study has shown that most of the dentists in this study prescribe panoramic radiographs in dental implant assessment based on broad coverage and cost. They are not following the American Academy of Oral and Maxillofacial Radiology recommendations regarding cross-sectional imaging.

[The place of radiography in endodontic treatment carried out in general practice in Dakar]. / Place de la radiographie dans les traitements endodontiques réalisés en omnipratique à Dakar.

An investigation conducted over dental surgeons of 52 dental offices in Dakar and it's near suburb (40 from private sector and 12 from public and quasi-public) has shown that the use of retro-alveolar radiography during endodontic treatment was not systematic, due to the price of retro-alveolar film, waste of time and relative facility of the endodontic treatment of monoradicular teeth. The preparatory negative is favored (32.70%) particularly by private dental surgeons, who use two retro-alveolar films for endodontic treatment: pre and post operative radiography (30%). The immediate post operator control is executed only in case of post-operator pains by public and quasi-public dental surgeons (16.67%) with one retro-alveolar film on average for the endodontic treatment; at term any radiographic control is done. Three retro-alveolar films per endodontic treatment were exceptionally used (9.61%) and offset incidences (15%) are not much used as well as support-films (angulators). The retro-alveolar radiography is still a reliable guide for a clinical success in endodontic treatment with a minimum of three retro-alveolar films and offset incidences.

[X-ray diagnostic apparatus in dentistry (a review)]. / Rentgenodiagnosticheskaia apparatura v stomatologii (obzor).

The X-ray dental equipment and photo-developing devices used for dentistry in Russia, the absorbed doses per tooth examination, and allied digital (sensory) transducers are considered.