Web-based Fully Automated Cephalometric Analysis: Comparisons between App-aided, Computerized, and Manual Tracings

Objective:To compare the accuracy of cephalometric analyses made with fully automated tracings, computerized tracing, and app-aided tracings with equivalent hand-traced measurements, and to evaluate the tracing time for each cephalometric analysis method.Methods:Pre-treatment lateral cephalometric radiographs of 40 patients were randomly selected. Eight angular and 4 linear parameters were measured by 1 operator using 3 methods: computerized tracing with software Dolphin Imaging 13.01(Dolphin Imaging and Management Solutions, Chatsworth, Calif, USA), app-aided tracing using the CephNinja 3.51 app (Cyncronus LLC, WA, USA) , and web-based fully automated tracing with CephX (ORCA Dental AI, Las Vegas, NV). Correction of CephX landmarks was also made. Manual tracings were performed by 3 operators. Remeasurement of 15 radiographs was carried out to determine the intra-examiner and inter-examiner (manual tracings) correlation coefficient (ICC). Inter-group comparisons were made with one-way analysis of variance. The Tukey test was used for post hoc testing.Results:Overall, greater variability was found with CephX compared with the other methods. Differences in GoGn-SN (°), I-NA (°), I-NB (°), I-NA (mm), and I-NB (mm) were statistically (p<0.05) and clinically significant using CephX, whereas CephNinja and Dolphin were comparable to manual tracings. Correction of CephX landmarks gave similar results to CephNinja and Dolphin. All the ICCs exceeded 0.85, except for I-NA (°), I-NB (°), and I-NB (mm), which were traced with CephX. The shortest analyzing time was obtained with CephX.Conclusion Fully automatic analysis with CephX needs to be more reliable. However, CephX analysis with manual correction is promising for use in clinical practice because it is comparable to CephNinja and Dolphin, and the analyzing time is significantly shorter

Interceptive Treatment Of Palatally Displaced Canines Studies of treatment effect and patients’ perception and methodological evaluation of 3D measurements of CBCT

Background: In 2 % of the Swedish population the canine fails to erupt and in 85 % of the cases the canine is palatally displaced. The most common interceptive treatment of palatally displaced canines (PDCs) is extraction of the deciduous canine at the age of 10-13 years and follow-up of the canine for 12 months to monitor whether its eruption path will normalize. In case the canine does not erupt spontaneously, a surgical exposure and orthodontic treatment is commonly considered. However, an early and easy interceptive treatment is preferable both from a health economic perspective as well as to reduce the risk of root resorption of the adjacent teeth and to avoid later comprehensive treatment/s. Objective: The aims of this thesis were: to develop a reliable and valid method to measure the position of PDCs on 3D images (Cone Beam Computed Tomography, CBCT) (paper I). To evaluate children’s subjective experience before, during and after extraction of the deciduous canine (paper II). To compare whether extraction of the deciduous canine more often results in spontaneous eruption of the permanent canine compared to non extraction (paper III) and to find out which clinical cases benefit from interceptive extraction (paper IV). Materials and Methods: In total 89 PDCs in 67 children (10-13 years of age) were randomly assigned to either have their deciduous canine extracted (extraction group, EG) or not extracted (control group, CG). Clinical and radiographic examinations were carried out at baseline (T0), after 6 (T1) and 12 months (T2) in both groups. 3D images of 20 patients out of 67 were randomly chosen and measured by two dentists at different occasions. The validity of the method to measure the displaced canines was assessed by comparing measurements on the 3D images with measurements on a dry skull. Children who had extraction of the deciduous canine were asked to answer a questionnaire before, the same day as and one week after the extraction. Results: • The radiographic method to measure and assess the position of the PDCs on 3D images was reliable and had a high validity (paper I). • The reported pain and discomfort were in overall low. The injection was experienced as more painful compared to the extraction, and analgesics were taken the first evening by 42 % of the children (paper II). • Extraction of the deciduous canine resulted in eruption of the PDCs in 69 % of the cases compared to 39% in the CG. Significantly more positional changes and a shorter mean eruption time were seen in the EG (paper III). • PDCs with a mesioangular angle of 103°, distance of the canine cusp tip-dental arch plane of 2.5 mm and distance of the canine cusp tip-midline of 11 mm in patients 11-12 years old, will not erupt spontaneously in spite of interceptive extraction of the deciduous canine (paper IV). Conclusions: The radiographic method to measure and assess the position of the PDCs was reliable and valid and can be used in future studies. Adequate analgesics and dose should be given to children before and after extracting the deciduous canine. Interceptive extraction of the deciduous canine at 10-13 years of age was effective and will result in significantly more spontaneous eruptions of the permanent canine compared to a control group. The cutoff points may be a helpful tool for the clinician to chose whether the patient benefit from interceptive extraction of the deciduous canine or whether immediate surgical exposure should be performed

Soft tissue profile changes after vertical ramus osteotomy

Patients with mandibular prognathism have, for a number of years, been treated by orthognathic surgery and post-surgical changes in the facial profile have been widely reported. However, little is known about the influence of gender and age on the soft tissues. The aim of this study was to investigate changes in the soft tissue profile following orthognathic surgery and to evaluate gender and age differences in the ratios of soft-to-hard tissue change. Forty-two Caucasian adults (18 males and 24 females) aged from 17 to 46 years with mandibular prognathism who underwent vertical ramus osteotomy were included. Lateral cephalograms were taken 2-8 months pre- (T1) and 12-19 months post- (T2) surgically. Five skeletal, two dental, and seven soft tissue parameters were hand traced. Paired and unpaired Student's t-tests, Pearson's correlation coefficients, and multiple regression analyses were used to evaluate the data. Due to the setback of the mandible, soft and hard tissues changed in a 1:1 ratio at the mentolabial fold and chin in females and 1:1,1 in males. Significant differences of soft-to-hard tissue ratios were found at points Pg (P < 0.05) and Gn (P < 0.01). Age effects on the ratios were not significant. Other effects of the mandibular setback on the soft tissue profile were a significant increase in facial convexity, a deepening of the mentolabial fold, an increase in lower lip thickness, and a decrease in upper lip thickness, which increased the nasolabial angle. These findings indicate that use of gender-specific ratios in treatment planning might improve the accuracy of predicting treatment result

Salivary levels of Osteoprotegerin and receptor activator of nuclear factor-kappa ligand during orthodontic tooth movement : A prospective pilot study

Objectives: The aim of this study was to monitor changes in Osteoprotegerin (OPG) and receptor activator of nuclear factor-kappa ligand (RANKL) levels in the saliva during orthodontic tooth movement (OTM). Materials and Methods: Nine healthy females (15-20 y of age) with four pre-molar extractions and fixed appliance were included. In total, 134 stimulated and 134 unstimulated saliva samples were collected: at baseline and then every 6-8 weeks at follow-up appointments during the whole orthodontic treatment. Twelve age-matched females with no active orthodontic treatment served as a control group. Saliva samples were analysed by enzyme-linked immunosorbent assay (Elisa). The mean levels of OPG and RANKL were calculated according to the different orthodontic treatment stages: alignment, space closure and finishing. A mixed model analysis was used to compare the means of treatment stages. Baseline OPG levels were compared with the control group using an independent t-test. OPG levels were measured in stimulated saliva due to low levels in unstimulated saliva. Results: No significant difference was observed between baseline OPG values and the control group. OPG increased significantly at all treatment stages: alignment, space closure and finishing compared with baseline (P = 0.002, P = 0.039, P = 0.001, respectively). The salivary levels of OPG increased gradually, except during space closure, reaching peak levels at finishing. RANKL was undetectable in stimulated and unstimulated saliva by sandwich Elisa during OTM. Conclusions: This novel approach shows the changes in the levels of OPG in OTM and indicates how and when to sample saliva during orthodontic treatment to analyse bone remodelling

A comparative study of cone beam computed tomography and conventional radiography in diagnosing the extent of root resorptions

Abstract Background Root resorptions are assessed and diagnosed using different radiographical techniques. A comparison of the ability to assess resorptions on two-dimensional (2D) and three-dimensional (3D) radiographs is, hitherto, lacking. The aims of this study were to evaluate the accuracy of 2D (periapical radiographs, PA and panoramic radiograph, PAN) and 3D (cone beam computed tomography, CBCT) radiographic techniques in measuring slanted root resorptions compared to the true resorptions, a histological gold standard, in addition to a comparison of all the radiographic techniques to each other. Methods Radiographs (CBCT, PA, and PAN), in addition to histological sections, of extracted deciduous canines from thirty-four patients were analyzed. Linear measurements of the most and least resorbed side of the root, i.e., “slanted” resorptions, were measured using an analyzing software (Facad ®). For classification of slanted root resorptions, a modified Malmgren index was used. Results PAN underestimated the root length on both the least and most resorbed side. Small resorptions, i.e., low modified Malmgren scores, were more difficult to record and were only assessed accurately using CBCT. The root resorption scores were underestimated using PA and PAN. In assessment of linear measures, PAN differed significantly from both CBCT and PA. Conclusions CBCT is the most accurate technique when measuring and scoring slanted root resorptions

Monitoring Salivary Levels of Interleukin 1 Beta (IL-1β) and Vascular Endothelial Growth Factor (VEGF) for Two Years of Orthodontic Treatment: A Prospective Pilot Study

Background and Objective. Vascular endothelial growth factor (VEGF) and interleukin 1 beta (IL-1β) perform functions in orthodontic tooth movement and can be measured in the saliva. This novel approach is aimed at monitoring continuous changes in IL-1β and VEGF levels in saliva during two years of orthodontic treatment. Material and Methods. Nine healthy females (15-20 years of age) with crowding requiring four premolar extractions and fixed appliances in both jaws were included in this prospective pilot study. A total of 134 stimulated and 134 unstimulated saliva samples were collected during two years of treatment: before tooth extractions (baseline) and then every 6-8 weeks at follow-up appointments. All saliva samples were analysed by the enzyme-linked immunosorbent assay. The mean levels of IL-1β and VEGF were calculated according to the different orthodontic treatment stages: alignment, space closure, and finishing. Repeated analysis of variance (ANOVA) measurements were used to compare the means between different treatment stages. The percentage difference in IL-1β and VEGF between the different treatment stages was analysed by Bland-Altman plots. Results. A gradual increase in IL-1β and VEGF was observed at alignment, reaching significance at space closure (p=0.002 and p=0.025, respectively). At finishing, both IL-1β and VEGF declined, however, without reverting to baseline values (p=0.172 and p=0.207, respectively). Bland-Altman analysis showed the agreement between IL-1β and VEGF in terms of a systematic increase, with a higher percentage difference for VEGF. Conclusions. The salivary levels of both IL-1β and VEGF increased following orthodontic treatment and reached their peaks during the treatment stage of space closure. This novel approach provides a hint on how and when to sample saliva during orthodontic treatment to analyse bone remodelling