Ink-jet printout of radiographs on transparent film and glossy paper versus monitor display: an ROC analysis

The aim of this study was to compare the depiction ability of small grayscale contrasts in ink-jet printouts of digital radiographs on different print media with CRT monitor. A CCD-based digital cephalometric image of a stepless aluminum wedge containing 50 bur holes of different depth was cut into 100 isometric images. Each image was printed on glossy paper and on transparent film by means of a high-resolution desktop inkjet printer at specific settings. The printed images were viewed under standardized conditions, and the perceptibility of the bur holes was evaluated and compared to the perceptibility on a 17-in CRT monitor. Thirty observers stated their blinded decision on a five-point confidence scale. Areas (Az) under receiver operating characteristics curves were calculated and compared using the pair wise sign tests. Overall agreement was estimated using Cohen's kappa device and observer bias using McNemar's test. Glossy paper prints and monitor display revealed significantly higher (P < 0.001) average Az values (0.83) compared to prints on transparent film (0.79), which was caused by higher sensitivity. Specificity was similar for all modalities. The sensitivity was dependent on the mean gray scale values for the transparent fil

The influence of ambient lighting on the detection of small contrast elements in digital dental radiographs

Objectives: The aim of this study was to evaluate the effect of ambient light on the detection of contrast elements in digital dental radiographs. Materials and methods: A high-contrast standardized digital radiograph of an aluminum step wedge containing 32 boreholes of different depth was cut into 40 isometric images. Images were presented at random on a 17-in cathode ray tube (CRT) monitor at different ambient background illuminations of 0, 50, 200, and 500lx. Twenty observers stated twice their blinded decision whether or not they could perceive a dark spot on a five-point confidence scale. Areas (Az) under receiver operating characteristic curves were calculated and compared between the four different ambient illuminations using the Friedman test. Statistical significance was set at p < 0.05. Overall agreement was estimated determining the intraclass correlation coefficient. Results: The Az values (0.735 for 0lx, 0.728 for 50lx, 0.735 for 200lx, and 0.788 for 500lx) did not significantly differ (p = 0.796) between the four ambient lighting levels. Conclusions: The detection of small contrast features in digital dental radiographs on a CRT monitor seems to be comparable over a wide range of ambient background illumination. Clinical relevance: The ambient light in dental offices of <500lx may not negatively impact the diagnostic performance of digital dental radiograph

Prevalence and correlation with sex, age, and dental status of bone apposition at the mandibular angle and radiographic alterations of the temporomandibular joints: a retrospective observational study in an adult Swiss population

Abstract Background The purpose of this study was to determine the prevalence of radiographic changes in the mandibular angle (bone apposition) and osseous alterations in the temporomandibular joints (TMJs) in the adult population of Switzerland. In addition, the study intended to investigate possible correlations between the two sites of contour bone changes (mandibular angle and TMJ) and to analyze various patient-related factors, including sex, age, dental status, and medical history. Methods Panoramic radiographs of 600 patients distributed into six age groups (283 females, 317 males, aged 20 to 79 years) were included to evaluate radiographic changes. The bone in the mandibular angle region and the shape of the condylar heads were examined for contour changes (bone apposition at the jaw angles and osseous changes of the TMJs). General estimating equations, binormal tests, and chi-squared tests were used for statistical analysis. Results Approximately half of the mandibular angles (47.8%) showed bone apposition, mostly bilateral. TMJ alterations were less common (27%), often unilateral, with flattening being the most frequent finding. No significant correlation was found between the two sites. Bone apposition at the mandibular angle showed a significant male predominance, whereas TMJ changes did not differ by sex. Alterations in both sites increased with age, and were not related to dental status or analgesic use. Conclusions Bone apposition at the mandibular angle should be interpreted as part of the natural functional adaptation of the bone associated with aging. Assuming that parafunctional habits may influence the development and progression of alterations in the mandibular angle or TMJs, the presence of radiographic changes in these areas should prompt dental clinicians to investigate further in this direction. Trial registration The study was approved by the Swiss Association of Research Ethics Committees (swissethics), BASEC reference number: 2020–00963 (25.05.2020)

Comparison of Two-Dimensional and Three-Dimensional Radiographs Using Clinically Relevant Parameters

This work compared the assessment of clinically relevant parameters by two-dimensional, that is, full-mouth intraoral radiograph (I-O) and panoramic radiograph (OPT), and three-dimensional, that is, cone beam computed tomography (CBCT), imaging methods. Different radiographic images (CBCT, I-O and OPT) were available for a 53-year-old female patient with dental and periodontal problems. A total of 14 dental and periodontal parameters were assessed by two independent examiners and compared among the three radiographic imaging modalities. For 10 parameters (71%), the CBCT images were superior to both I-O and OPT images. In contrast, CBCT demonstrated an inferior performance compared to I-O and OPT in the assessment of caries and dental restorations. Compared to OPT, I-O provided more clinically relevant findings for 10 out of 14 parameters (71%). Agreement between I-O and OPT was found with respect to dehiscence, fenestration, the number of bone walls and the root canal cross-section. Differences between the radiographic images were more likely to be detected when maxillary teeth rather than mandibular teeth were assessed with regard to furcation involvement, root proximity and root fusion

Accuracy of Guided Endodontics in Posterior Teeth

The purpose of this ex vivo study was to determine the accuracy of template-based guided endodontics for access cavity preparation and root canal detection in posterior teeth. First, three maxillary and four mandibular models were constructed using 67 premolars and molars, with a total number of 135 main root canals. Cone beam computed tomography (CBCT) and three-dimensional 3D surface scans of each model were performed and matched in order to plan access cavity preparation and design templates virtually. Template-guided access cavity preparation was then performed for each tooth, followed by postoperative CBCT scanning. Deviations between planned and prepared access cavities were measured after superimposition of the pre- and postoperative CBCT scans, and they were analyzed using descriptive and multivariate statistics. All root canals (135/135) were detected utilizing guided endodontics. The mean angle deviation was 1.4 degrees, and the mean deviations at the tip and base of the bur were 0.24–0.31 mm and 0.26–0.29 mm, respectively. This study demonstrated that guided endodontics is an accurate and predictable method for endodontic access cavity preparation in posterior teeth

Guided endodontics versus conventional access cavity preparation: an ex vivo comparative study of substance loss

Abstract Background To compare the outcomes of conventional access cavity preparation (CONV) versus guided endodontics (GE) for access cavity preparation in anterior teeth with pulp canal calcification (PCC) regarding root canal detection, substance loss, procedural time, and need for additional radiographs. Methods Extracted, sound human teeth with PCC (n = 108) were matched in pairs, divided into two groups and used to produce 18 models. An independent endodontist and a general dentist performed access cavity preparation under simulated clinical conditions on nine models each (54 teeth). The endodontist used the conventional technique and the general dentist GE. Time needed to access the root canals and the number of additional radiographs were recorded. Pre- and postoperative cone-beam computed tomography scans were obtained to measure substance loss. Statistical significance was tested by examining the overlap of 95% confidence intervals (CIs) between the groups. Results All root canals were successfully accessed by both methods. There were no significant differences in substance loss (CI: CONV 15.9–29.6 mm3 vs. GE 17.6-27.5mm3) or procedural time (CI: CONV 163.3-248.5 s vs. GE 231.9-326.8 s). However, 31 additional radiographs were required for GE compared to none for CONV. Conclusions For access cavity preparation in teeth with PCC, both CONV by a specialist and GE by a general dentist produce good results in terms of substance loss and time requirements

Gesichtsschmerzen – eine seltene Ursache : Retinierte untere Weisheitszähne als Ursache für zunächst «unklare» Gesichtsschmerzen. Ein Fallbericht

Orofacial pain often causes special difficulties to patients and dentists. Numerous differential diagnoses require the utilization of a coordinated diagnostic concept. Often, multiple causes lead to the need for a complex treatment plan. Impacted third molars are a potential cause of a variety of complications. Caries, pulp necrosis, and periapical infection are some of the infrequent causes of such pain. The presented case shows just such a constellation, resulting in primarily "unclear" orofacial pain. A diagnostic sequence generally leads to the correct diagnosis and thereby allows for fast and effective therapy. This shows how important structured diagnostics are, especially in cases of "unclear" pain

Is furcation involvement in maxillary molars a predictor for subsequent bone augmentation prior to implant placement? A pilot study

AIM: The aim of this pilot study was to analyze the interfurcal bone height in relation to the possible need for subsequent sinus floor elevation in patients with advanced periodontitis and furcation involvement of first and/or second maxillary molars. MATERIAL AND METHODS: Seventeen dentate patients, who received cone beam computed tomography (CBCT) for detailed preoperative diagnosis and planning of surgical interventions at periodontally involved maxillary molars (17 first and 15 second molars), were consecutively recruited for the study. The minimal bone height in the interfurcal region was measured from CBCT and related to furcation involvement, residual bone above the root tips, and the clinical probing pocket depth (PPD). RESULTS: The minimal interfurcal bone height measured 4.1 ± 2.6 mm on average with 75% of maxillary molars having ≤ 6 mm and almost 60% having only ≤ 4 mm bone height left below the sinus floor. A higher risk for reduced interfurcal bone height of ≤ 4 mm was given when residual PPD of ≥ 6 mm was remaining at two or more tooth sites (OR 0.10; 0.11). CONCLUSIONS: The majority of periodontally involved maxillary molars had a substantially reduced interfurcal bone height, particularly with at least two sites with residual PPD ≥ 6 mm. This was a predictor for a subsequent need for sinus floor elevation when tooth replacement with a dental implant is desired

SADMFR Guidelines for the Use of Cone-Beam Computed Tomography/Digital Volume Tomography

In 2011, the first consensus conference on guidelines for the use of cone-beam computed tomography (CBCT) was convened by the Swiss Society of Dentomaxillofacial Radiology (SGDMFR). This conference covered topics of oral and maxillofacial surgery, temporomandibular joint dysfunctions and disorders, and orthodontics. In 2014, a second consensus conference was convened on guidelines for the use of CBCT in endodontics, periodontology, reconstructive dentistry and pediatric dentistry. The guidelines are intended for all dentists in order to facilitate the decision as to when the use of CBCT is justified. As a rule, the use of CBCT is considered restrictive, since radiation protection reasons do not allow its routine use. CBCT should therefore be reserved for complex cases where its application can be expected to provide further information that is relevant to the choice of therapy. In periodontology, sufficient information is usually available from clinical examination and periapical radiographs; in endodontics alternative methods can often be used instead of CBCT; and for implant patients undergoing reconstructive dentistry, CT is of interest for the workflow from implant planning to the superstructure. For pediatric dentistry no application of CBCT is seen for caries diagnosis