The outcome of an automated assessment of trabecular pattern in intraoral radiographs as a fracture risk predictor.

OBJECTIVES: This study aims to investigate if automated analyses of the trabecular pattern in intraoral radiographs independently contribute to fracture risk assessment when other risk factors incorporated in the Fracture Risk Assessment Tool (FRAX) are taken into account. A secondary aim is to explore the correlation between the automated trabecular pattern assessment in intraoral radiographs and Trabecular Bone Score (TBS). METHODS: A total of 567 intraoral radiographs from older females participating in a large population-based study (SUPERB) based in Gothenburg, Sweden, were selected to analyse trabecular pattern using semi-automated and fully automated software. Associations between trabecular pattern analysis and incident fractures were studied using Cox proportional hazard model, unadjusted and adjusted for FRAX risk factors (previous fracture, family history of hip fracture, smoking, corticosteroids, rheumatoid arthritis, without and with bone mineral density (BMD) of the femoral neck). In addition, the correlation between trabecular pattern analysis and TBS of the lumbar spine was investigated using Pearson correlation analysis. RESULTS: Neither the unadjusted nor the adjusted trabecular pattern analysis in intraoral radiographs was significantly associated with any fracture or major osteoporotic fracture (MOF). A weak correlation was found between semi-automated trabecular pattern analysis and TBS. No correlation was found between the fully automated trabecular pattern analysis and TBS. CONCLUSIONS: The present study shows that semi-automated and fully automated digital analyses of the trabecular pattern in intraoral radiographs do not contribute to fracture risk prediction. Furthermore, the study shows a weak correlation between semi-automated trabecular pattern analysis and TBS.

The challenge of applying digital image processing software on intraoral radiographs for osteoporosis risk assessment.

OBJECTIVES: The purpose of this study was to evaluate rater agreement and the accuracy of a semi-automated software and its fully automated tool for osteoporosis risk assessment in intraoral radiographs. METHODS: A total of 567 intraoral radiographs was selected retrospectively from women aged 75-80 years participating in a large population-based study (SUPERB) based in Gothenburg, Sweden. Five raters assessed participants' risk of osteoporosis in the intraoral radiographs using a semi-automated software. Assessments were repeated after 4 weeks on 121 radiographs (20%) randomly selected from the original 567. Radiographs were also assessed by the softwares' fully automated tool for analysis. RESULTS: Overall interrater agreement for the five raters was 0.37 (95% CI 0.32-0.41), and for the five raters with the fully automated tool included as 'sixth rater' the overall Kappa was 0.34 (0.30-0.38). Intrarater agreement varied from moderate to substantial according to the Landis and Koch interpretation scale. Diagnostic accuracy was calculated in relation to reference standard for osteoporosis diagnosis which is T-score values for spine, total hip and femoral neck and presented in form of sensitivities, specificities, predictive values, likelihood ratios and odds ratios. All raters' mean sensitivity, including the fully automated tool, was 40,4% (range 14,3%-57,6%). Corresponding values for specificity was 69,5% (range 59,7%-90,4%). The diagnostic odds ratios ranged between 1 and 2.7. CONCLUSION: The low diagnostic odds ratio and agreement between raters in osteoporosis risk assessment using the software for analysis of the trabecular pattern in intraoral radiographs shows that more work needs to be done to optimise the automation of trabecular pattern analysis in intraoral radiographs.

A rater agreement study on measurements in cross-sectional CBCT images exploring the association between alveolar bone morphology and craniofacial height.

OBJECTIVES: To investigate rater agreement regarding measurements of height and width of the maxilla and mandible using cross-sectional images from CBCT examinations. Furthermore, to explore the association between vertical craniofacial height and alveolar bone morphology. METHODS: Pre-treatment CBCT scans from 450 patients referred for treatment to a private clinic for orthodontics and oral surgery in Scandinavia were available and of these, 180 were selected. Lateral head images were generated from the CBCT volumes to categorise subjects into three groups based on their craniofacial height. Cross-sectional images of the maxillary and mandibular bodies at three locations in the maxilla and mandible, respectively, were obtained and measured at one height and two width recordings by five raters. One-way analysis of variance with a Tukey post hoc test was performed. A significance level of 5% was used. RESULTS: Rater agreement was mostly excellent or good when measuring height and width of the maxilla and mandible in cross-sectional CBCT images. For height (of the alveolar bone/bodies), there were statistically significant differences between the low- and the high-angle groups for all the observers when measuring in the premolar and midline regions, both in the maxilla and in the mandible. CONCLUSION: The high agreement found ensures a reliable measurement technique and confirms the relation between craniofacial height and alveolar bone height and width.

A tool for assessment of risk of bias in studies of adverse effects of orthodontic treatment applied in a systematic review on external root resorption.

BACKGROUND AND AIMS: Systematic reviews (SRs) are considered to provide reliable estimates, but flaws in designs, methods of monitoring effects, and outcomes have the potential to bias results. There are several tools for assessing risk of bias (RoB), most of them designed for SRs of beneficial effects. To our knowledge, there is no tool that is adapted specifically to assess RoB in studies of adverse effects associated with orthodontic treatment. To address this, the aim of this study was first to introduce a tool for assessment of RoB in studies of adverse effects associated with orthodontic treatment and, second, to apply it in an SR of external root resorption (ERR) associated with orthodontic treatment with fixed appliance. MATERIALS AND METHODS: The approach with domains supported by signalling questions was used for the tool. Domains and signalling questions were tailored to the review questions of the SR of studies of ERR after orthodontic treatment using periapical radiography or cone beam computed tomography. Duplicate study selection, data extraction, and RoB assessment using the tool, followed by meta-analyses, were performed. RESULTS: Using the tool for the assessment of RoB identified shortcomings and report deficiencies of primary studies concerning the presentation of orthodontic treatment, identification of ERR, and analysis of outcomes. RoB assessment resulted in 12 of 32 studies read in full text being included. Reported severe ERR varied across studies between 2 and 14 per cent for all incisors and 10 and 29 per cent for maxillary incisors. Results of ERR related to patients' age and sex, orthodontic diagnosis, and treatment were contradictory. Quality of evidence evaluated by GRADE was low due to study limitations, imprecision, and inconsistency of study results. CONCLUSIONS: As the tool and its application highlight important issues to consider when planning, conducting, and reporting research, the tool may have a valuable role for quality enhancement of future studies of outcomes of orthodontic treatment. The tool may also serve for authors when planning SRs. Our SR identified a need for studies that use rigorous methodology and transparent reporting. REGISTRATION: PROSPERO (ID = CRD42018084725).

Osteoporosis risk assessment in primary dental care-The attitudes of Swedish dentists, patients and medical specialists.

OBJECTIVE: To explore and identify the attitudes of dentists, patients and medical specialists regarding implementation of osteoporosis risk assessment into Swedish primary dental care. BACKGROUND: Osteoporosis is a major health problem leading to fragility fractures. As shown in academic-based research, dental radiological examination can be used for osteoporosis risk assessment. A substantial number of patients undergo radiographic examinations in primary dental care each year, but little is known about implementation of osteoporosis risk assessment in this setting. MATERIALS AND METHODS: A qualitative research approach using focus group discussions and manifest content analysis was applied. Five focus groups with dentists and representatives from patient support groups and a single individual interview with one medical specialist were included in the sample. RESULTS: From the manifest content analysis, three categories emerged: (a) barriers to change in practice, (b) benefits to change in practice, and (c) needs and requirements prior to change in practice. Most participants felt that there was insufficient knowledge of osteoporosis as well as a heavy existing workload. A concern was expressed about medical practitioners' willingness to take on responsibility for patients referred by dentists. Representatives from patient support groups highlighted a lack of knowledge about osteoporosis among both the general public and the medical professionals. Clear guidelines and improved communication channels between stakeholders would have to be established to ensure a smooth treatment path for patients. CONCLUSION: Despite interest in osteoporosis risk assessment in primary dental care, there are political, workflow and educational barriers that must be overcome for successful implementation.

Through the quality kaleidoscope: reflections on research in dentomaxillofacial imaging.

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

Willingness to pay for osteoporosis risk assessment in primary dental care.

BACKGROUND: Fragility fracture related to osteoporosis among postmenopausal women is a significant cause of morbidity. The care and aftercare of these fractures are associated with substantial costs to society. A main problem is that many individuals suffer from osteoporosis without knowing it before a fracture happens. Dentists may have an important role in early identification of individuals with osteoporosis by assessment of dental radiographs already included in the dental examination. The aim of this study was therefore to investigate postmenopausal women's preferences for an osteoporosis risk assessment in primary dental care. RESULTS: Most respondents (129 of 144 (90%)) were willing to pay for an osteoporosis risk assessment in primary dental care. The overall mean willingness to pay (WTP) including respondents that denoted none or zero WTP was 44.60 € (CI 95% 38.46-50.74 €) (median 34.75 €). A majority (80.6%) of the respondents that denoted WTP also gave a motivation for their answer. The two most common reasons denoted for being willing to pay for osteoporosis risk assessment were the importance of early diagnosis and preventive care to avoid fractures (41.0%) and the importance of knowledge of a risk of osteoporosis (26.4%). A majority of respondents (67.8%) considered it valuable if dental clinics would offer osteoporosis risk assessment. CONCLUSIONS: Postmenopausal women seem to find it valuable to be offered osteoporosis risk assessment in primary dental care and are willing to pay for such a risk assessment. From a societal perspective early diagnosis of osteoporosis by risk assessment in primary dental care could prevent osteoporotic related fractures and benefit women's health and quality of life, as well as have a major impact on the health-care budget in terms of cost-savings.

Measurability and reliability of assessments of root length and marginal bone level in cone beam CT and intraoral radiography: a study of adolescents.

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

The impact of premature birth on dental maturation in the permanent dentition.

OBJECTIVES: To evaluate tooth development and calculate dental maturity score in prematurely born children and to compare the findings with full-term born children. MATERIAL AND METHODS: Nine-year-old preterm children were selected from the Swedish Medical Birth Register. One group consisted of 36 extremely preterm children (born before week 29), and the other included 38 very preterm children (born during weeks 29 to 32). Panoramic radiography was performed on each child and the preterm children were compared with 42 full-term born children. Five observers independently assessed the tooth development stages for all teeth in the left mandible (31-37) on the panoramic radiographs according to the method described by Demirjian et al. (Hum Biol 45:211-227, 1973). Data from tooth development stages were compiled and converted into a dental maturity score for each group. Kappa values were calculated for intra- and inter-observer agreement. RESULTS: When the different development stages for each individual tooth were compared, all observers presented a significant delay in the maturity of tooth 37 for the extremely preterm group (p ≤ 0.002). The extremely preterm group had a significantly lower dental maturity score than the full-term group, as assessed by each observer (p ≤ 0.006). Kappa values for inter-observer agreement varied between 0.31 and 0.71 depending on tooth and intra-observer agreement was between 0.16 and 1.0. CONCLUSIONS: At age 9, the extremely preterm children had a general delay in tooth development. CLINICAL RELEVANCE: The increased survival rate of extremely preterm babies adds a new group of children to society. Dental clinicians should be aware that the delay in tooth development could impact the timing of orthodontic diagnostics and potential treatment.

The impact of Cone Beam CT on financial costs and orthodontists' treatment decisions in the management of maxillary canines with eruption disturbance.

Background: Examination with Cone Beam CT (CBCT) is common for localizing maxillary canines with eruption disturbance. The benefits and costs of these examinations are unclear. Objectives: To measure: 1. the proportion of orthodontists' treatment decisions that were different based on intraoral and panoramic radiography (M1) compared with CBCT and panoramic radiography (M2); and 2. the costs of producing different treatment plans, regarding patients with maxillary canines with eruption disturbance. Subjects and methods: Orthodontists participated in a web-based survey and were randomly assigned to denote treatment decisions and the level of confidence in this decision for four patient cases presented with M1 or M2 at two occasions for the same patient case. Results: One hundred and twelve orthodontists made 445 assessments based on M1 and M2, respectively. Twenty-four per cent of the treatment decisions were different depending on which method the raters had access to, whereof one case differed significantly from all other cases. The mean total cost per examination was €99.84 using M1 and €134.37 using M2, resulting in an incremental cost per examination of €34.53 for M2. Limitations: Benefits in terms of number of different treatment decisions must be considered as an intermediate outcome for the effectiveness of a diagnostic method and should be interpreted with caution. Conclusions: For the patient cases presented in this study, most treatment decisions were the same irrespective of radiological method. Accordingly, this study does not support routine use of CBCT regarding patients with maxillary canine with eruption disturbance.

Craniofacial height in relation to cross-sectional maxillary and mandibular morphology.

BACKGROUND: In order to gain a better understanding of how growth of the alveolar bone is linked to the vertical development of the face, the purpose of this study was to investigate if there is an association between the cross-sectional morphology of the maxillary and mandibular bodies with the craniofacial height, using images from cone beam computed tomography (CBCT). METHODS: From 450 pre-treatment CBCT scans, 180 were selected to be included in the study. Lateral head images were generated from the CBCT scans and were used to categorise subjects into three groups based on their vertical craniofacial height. Cross-sectional images from CBCT volumes were reformatted of the maxillary and mandibular bodies at five locations in the maxilla and five in the mandible. Each image was measured at one height and two width measurements. Statistical analysis performed was the one-way analysis of variance with a Tukey post hoc test. A significance level of 5% was used in all comparisons. RESULTS: Patients with large vertical craniofacial height had a significantly higher cross-sectional area both in the maxilla and in the mandible. In the same group, the cross-sectional area was significantly thinner in the mandible compared with the other two groups, especially in the anterior region. CONCLUSIONS: This study further highlights the close relationship between craniofacial height and alveolar bone dimensions and contributes with important knowledge for planning and follow-up of comprehensive dental- and orthodontic treatments.

One-piece internal zirconia abutments for single-tooth restorations on narrow and regular diameter implants: A 5-year prospective follow-up study.

BACKGROUND: Studies have reported an increased risk for fractures of zirconia abutments compared with titanium abutments. PURPOSE: The aim of this study was to evaluate single-tooth implant restorations with one-piece yttria-stabilized internal zirconia abutments on narrow and regular diameter implants up to 6 years after insertion. MATERIAL AND METHODS: This study comprises 52 consecutively treated patients, with a median age of 19 years. In total, 59 narrow (3.3 mm) and 10 regular (4.1 mm) diameter implants were installed. Sixty-five all-ceramic crowns were cemented on implant-supported one-piece internal zirconia abutments and 4 restorations were screw-retained. RESULTS: Thirty-five patients with 48 implant restorations participated in the final examination and another 14 patients with 16 implant restorations were possible to reach and could be interviewed. The implant survival was 100% but the survival rate for the implant-supported ceramic restorations was lower, 87.5%. Three crowns (4.7%) were remade for different reasons. Five restorations (7.8%) were remade due to fracture of the internal one-piece zirconia abutment. Four of these fractures occurred in 3.3 mm implant abutments. CONCLUSIONS: Narrow diameter implants offer an opportunity to restore small single-tooth edentulous gaps. For esthetical reasons the choice of an abutment in zirconia can be favorable, but at least with the used implant system, there seems to be an increased risk for fracture. Most patients were very satisfied with the esthetics and function of their implant restorations.

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

OBJECTIVES: To investigate the relationship between dose and image quality for a dedicated dental CBCT scanner using different scanning protocols and to set up an optimal imaging protocol for assessment of periodontal structures. METHODS: Radiation dose and image quality measurements were made using 3D Accuitomo 170 (J. Morita, Kyoto, Japan) dental CBCT scanner. The SedentexCT IQ phantom was used to investigate the relationship between contrast-to-noise ratio (CNR) and dose-area product. Subjective image quality assessment was achieved using a small adult skull phantom for the same range of exposure settings. Five independent observers assessed the images for three anatomical landmarks using a three-point visual grade analysis. RESULTS: When correlating the CNR of each scanning protocol to the exposure parameters used to obtain it, CNR decreased as these parameters decreased, especially current-exposure time product. When correlating to subjective image quality, the CNR level remained acceptable when 5 mA and 17.5 s or greater was selected and 80 kV could be used without compromising the CNR. CONCLUSIONS: For a dedicated CBCT unit, changing the rotation angle from 360° to 180° degrades image quality. By altering tube potential and current for the 360° rotation protocol, assessment of periodontal structures can be performed with a smaller dose without substantially affecting visualization.

The Influence of Tactile Perception on Classification of Bone Tissue at Dental Implant Insertion.

BACKGROUND: Various ways of using the Lekholm and Zarb (L&Z) classification have added to the lack of scientific evidence of the effectiveness of this clinical method in the evaluation of implant treatment. PURPOSE: The study aims to assess subjective jawbone classifications in patients referred for implant treatment, using L&Z classification with and without surgeon's hand perception at implant insertion. The association between bone type classifications and quantitative parameters of primary implant stability was also assessed. MATERIALS AND METHODS: One hundred thirty-five implants were inserted using conventional loading protocol. Three surgeons classified bone quality at implant sites using two methods: one based on periapical and panoramic images (modified L&Z) and one based on the same images associated with the surgeon's tactile perception during drilling (original L&Z). Peak insertion torque and implant stability quotient (ISQ) were recorded. RESULTS: The modified and original L&Z were strongly correlated (rho = 0.79; p < .001); Wilcoxon signed-rank test showed no significant difference in the distribution of bone type classification between pairs using the two methods (p = .538). Spearman correlation tested the association between primary stability parameters and bone type classifications (-0.34 to -0.57 [p < .001]). CONCLUSIONS: Tactile surgical perception has a minor influence on rating of subjective bone type for dental implant treatment using the L&Z classification.

Marginal bone level changes and implant stability after loading are not influenced by baseline microstructural bone characteristics: 1-year follow-up.

OBJECTIVE: The aim of this study was to investigate the influence of different bone tissue characteristics of implant sites on changes in marginal bone level and implant stability over time. MATERIAL AND METHODS: One hundred and one implants were inserted in 41 patients. Cortical bone thickness of the alveolar ridge was measured on computed tomography (CT) images. Histomorphometric and microtomographic analyses (microCT) were performed in bone specimens obtained by using a trephine bur, at first drilling. Implant stability quotient (ISQ) measured by resonance frequency analysis (RFA) was registered at implant insertion. Implant stability quotient was measured also at the stages of uncovering, loading and at the 1-year follow-up, when standardized periapical radiographs were taken to measure the marginal bone level (MBL). Descriptive statistics, Spearman's rho correlation and multiple linear regression were used for data analysis (P < 0.05). RESULTS: Comparison between groups of higher and lower values of ISQ changes and between groups of higher and lower values of MBL changes revealed no differences in histomorphometric and microtomographic parameters, according to non-parametric comparison tests, (P > 0.05). Bivariate correlation also showed no association among these microstructural parameters and the outcomes evaluated. There was no correlation between cortical thickness and MBL changes (r = -0.029; P = 0.832) and between cortical thickness and ISQ changes (r = 0.145; P = 0.292). CONCLUSION: Microstructural bone characteristics of implant sites have no effect on changes in marginal bone level and implant stability as measured by RFA. Bone morphology cannot predict implant treatment success over time.

Agreement between Histomorphometry and Microcomputed Tomography to Assess Bone Microarchitecture of Dental Implant Sites.

BACKGROUND: Histomorphometry and microcomputed tomography (microCT) have been used in implant studies but need better understanding before being used as equivalent methods. PURPOSE: The purpose of this study was to investigate the agreement between 2D (histomorphometry) and 3D (microCT) reference methods for assessing jawbone microarchitecture in vivo. MATERIAL AND METHODS: Forty-four bone specimens from 32 patients were obtained during implant placement and examined by microCT, followed by hematoxylin-eosin staining and histomorphometric analysis. The morphometric parameters included bone volume density (BV/TV), bone surface fraction (BS/TV), bone surface density, trabecular thickness, trabecular number, and trabecular separation (Tb.Sp). Bland-Altman plots were used for pairwise agreement analysis between the equivalent 3D and 2D parameters, and complemented with Mountain plots. The association between the two methods was tested using Pearson's correlation followed by Passing-Bablok regression. RESULTS: Systematic bias was observed in all Bland-Altman and Mountain plots, including constant bias for BV/TV and Tb.Sp, and proportional bias for all other parameters. Significant correlation was found for BV/TV (r = 0.80; p < .001) and BS/TV (r = 0.44; p = .003), and the Passing-Bablok regression showed constant bias for BV/TV and proportional bias for BS/TV. CONCLUSION: Because of the poor agreement between measures obtained by histomorphometry and microCT, these methods should not be used interchangeably for jawbones.

The effect of marginal bone level changes on the stability of dental implants in a short-term evaluation.

OBJECTIVES: To evaluate whether changes in marginal bone level (MBL) around implants, in sites with different bone types, affect the over time implant stability measured by resonance frequency analysis (RFA). MATERIAL AND METHODS: Seventy-eight implants were inserted into jawbones of 32 patients using a two-stage surgical protocol, and implant bone sites were grouped according to the Lekholm and Zarb bone classification. The implant stability quotient (ISQ) was measured by RFA at four time points: implant placement, uncovering, rehabilitation, and at 1-year follow-up after loading. The MBL was measured on periapical radiographs at uncovering and at 1-year follow-up. Percent change in bone level was calculated based on the difference between the implant length and height from the crestal bone level to the implant apex. Descriptive statistics, Pearson's correlation, and repeated-measures ANOVA were used for data analysis. RESULTS: Significant improvement of ISQ was found between implant insertion and uncovering surgery (P < 0.001), while no significant changes were detected throughout the remaining follow-up period. The greatest improvement of ISQ was observed for bone type 4, compared with the other groups (P < 0.001). Percent change in bone level had no effect on longitudinal measures of ISQ (P = 0.337). The ISQ difference between uncovering and 1 year after loading was not correlated with percent change in bone level (r = 0.16; P = 0.157). CONCLUSION: There was increased implant stability after implant placement, but it was not affected by changes in marginal bone level during the first year of loading.

Economic evaluation of diagnostic methods used in dentistry. A systematic review.

OBJECTIVES: To review the literature of economic evaluations regarding diagnostic methods used in dentistry. DATA SOURCES: Four databases (MEDLINE, Web of Science, The Cochrane library, the NHS Economic Evaluation Database) were searched for studies, complemented by hand search, until February 2013. STUDY SELECTION: Two authors independently screened all titles or abstracts and then applied inclusion and exclusion criteria to select full-text publications published in English, which reported an economic evaluation comparing at least two alternative methods. Studies of diagnostic methods were assessed by four reviewers using a protocol based on the QUADAS tool regarding diagnostic methods and a check-list for economic evaluations. The results of the data extraction were summarized in a structured table and as a narrative description. RESULTS: From 476 identified full-text publications, 160 were considered to be economic evaluations. Only 12 studies (7%) were on diagnostic methods, whilst 78 studies (49%) were on prevention and 70 (40%) on treatment. Among studies on diagnostic methods, there was between-study heterogeneity methodologically, regarding the diagnostic method analysed and type of economic evaluation addressed. Generally, the choice of economic evaluation method was not justified and the perspective of the study not stated. Costing of diagnostic methods varied. CONCLUSIONS: A small body of literature addresses economic evaluation of diagnostic methods in dentistry. Thus, there is a need for studies from various perspectives with well defined research questions and measures of the cost and effectiveness. CLINICAL SIGNIFICANCE: Economic resources in healthcare are finite. For diagnostic methods, an understanding of efficacy provides only part of the information needed for evidence-based practice. This study highlighted a paucity of economic evaluations of diagnostic methods used in dentistry, indicating that much of what we practise lacks sufficient evidence.

Bone tissue microarchitectural characteristics at dental implant sites part 2: correlation with bone classification and primary stability.

OBJECTIVE: To investigate in vivo the correlation between the bone microarchitecture of implant bone sites, bone tissue classification subjectively assessed in radiographs and primary implant stability. MATERIAL AND METHODS: Periapical and panoramic radiographs were obtained from 32 partially edentulous patients. Three surgeons classified bone quality at implant sites using two different methods: assessments in periapical and panoramic radiographs (PP) and according to the classification proposed by Lekholm and Zarb (L&Z). During the implant insertion, bone biopsies were taken, and three-dimensional parameters were measured by microcomputed tomography (microCT). Insertion torque value (ITV) and initial implant stability quotient (ISQ) were recorded at the moment of the implantation. ISQ was also recorded at the uncovering stage of a traditional implant protocol. RESULTS: Bone types 2 and 3 were the most prevalent classifications according to PP (54.3%) and L&Z (58.7%). The mean and standard deviation values of primary stability variables were 38.7(16.7) for ITV, 75.3 (7.7) for initial ISQ and 79.3 (6.8) for uncovering ISQ. Several microCT original and factor variables were found to correlate with bone tissue classifications and primary stability variables. L&Z correlated with architecture (r = 0.31; P < 0.05), density (r = -0.43; P < 0.01) and bulk (r = -0.35; P < 0.05), whereas ITV correlated with architecture (r = -0.40; P < 0.01) and density (r = 0.51; P < 0.01). Multiple linear regression analysis revealed that density and bulk explained 32% of the variability of L&Z bone classification, while density and architecture explained 42% of the variability of ITV. CONCLUSIONS: This study demonstrates the first step in validating L&Z classification. MicroCT provides objective and detailed quantitative data on bone microarchitecture. Intraosseous implant stability is mainly determined by the density of the bone. ITVs could be a good indicator of primary implant stability, whereas ISQs measurements have some limitations and should not be used alone.

Bone quality assessment in routine dental implant treatment among Brazilian and Swedish specialists.

OBJECTIVES: To investigate the interpretation and assessment of bone quality among Brazilian and Swedish specialist performing implant treatment. MATERIAL AND METHODS: A questionnaire was developed containing open and closed questions on attitudes, knowledge, and understanding of diagnostic methods for bone quality assessment. The questionnaire was sent by mail to dental implant specialists in Brazil while the Swedish version was Web-based and sent to specialists in periodontology and maxillofacial surgery. The response rate in the Brazilian group was 15.4% and in the Swedish group 36.5%. RESULTS: Most respondents in both groups considered bone quality to be an important parameter for implant treatment outcome. Among Swedish specialists, bone quality, however, was considered to be of low relevance. The most popular method for assessing bone quality among Swedish specialists was the hand-felt perception of drilling resistance followed by radiography. The Brazilian specialists more often used peak insertion torque. Most respondents classified bone quality, and both groups used the classification proposed by Lekholm & Zarb (Tissue-Integratedprosthesis: Osseointegration in Clinical Dentistry, 1985, Quintessence, Chicago) most frequently. CONCLUSION: Specialists in both countries considered bone quality to be an important parameter for implant treatment outcome, but there was no consensus neither on what bone quality means nor on how to assess bone quality.