Three-dimensional evaluation of secondary alveolar bone grafting in patients with unilateral cleft lip and palate: A 2-3 year post-operative follow-up.

OBJECTIVES: The present study aims to quantitatively assess secondary alveolar bone graft (SABG) resorption in unilateral cleft lip, alveolus and palate (UCLAP) patients in a 2-3 year longitudinal follow-up setting by using a validated 3D protocol. Furthermore, the potential relation of SABG resorption with maxillary canine position and a number of patient-related factors was investigated. METHODS: UCLAP patients who underwent SABG and had good quality CBCT images at the following timepoints were included in the study: pre-operative (T0), immediate (T1), 6 months (T2) and either 1-2 years (T3) or 2-3 years (T4) post-operative. The final bone grafted region was defined on the T1 scans and refined in the registered T0 scans. The bone graft after resorption was determined by applying threshold-based segmentation on the registered T2, T3 or T4 scans within the segmented bone graft volume. The position of the canines was determined at every timepoint at the cleft and non-cleft side. RESULTS: Forty-five UCLAP patients (mean age 9.0 ± 1.3 years) were included. In the first 6 months after SABG, 43.6% bone resorption was recorded. 2-3 years post-operative, 56% bone resorption was found if the maxillary canine was not yet erupted and 42.7% if it erupted through the graft. The vertical position of the canines was significantly higher on the cleft side at T3. CONCLUSIONS: The present study reports significant SABG resorption over time. However, no correlation was found between SABG resorption and canine position, nor between other patient-related factors.

Optimization of orofacial cleft imaging protocols using device-specific low-dose cone-beam computed tomography.

OBJECTIVE: The aim of this study was to present optimized device-specific low-dose cone-beam computed tomography (CBCT) protocols with sufficient image quality for pre-surgical diagnostics and three-dimensional (3D) modelling of cleft defects. METHODS: Six paediatric skulls were acquired, and an artificial bony cleft was created. A high-resolution CBCT scan acted as a reference standard (Accuitomo 170, Morita, Kyoto, Japan) for comparing eight low-dose protocols of Newtom VGi-evo (QR Verona, Cefla, Verona, Italy), which included Eco and Regular protocols with different field of views (FOVs). Delineation of lamina dura, cementoenamel junction (CEJ), trabecular bone and bony bridge were assessed. A 3D model of the defect was also evaluated. RESULT: The dose area product of low-dose protocols ranged from 31 to 254 mGy*cm2. Despite the dose difference of up to eight times between applied protocols, trabecular bone and CEJ exhibited appropriate image quality in all scans. However, Regular small FOV protocols (5 × 5 and 8 × 5 cm2), for both lamina dura and bony bridge, demonstrated a significant improvement in image quality compared to Eco FOV counterparts. Based on 3D defect analysis, no significant difference existed between low-dose protocols and the reference standard. CONCLUSION: The findings highlight the possibility of achieving a considerable reduction (up to eight times) in the radiation dose using low-dose CBCT protocols while maintaining sufficient image quality for assessing anatomical structures and 3D modelling in cleft cases.

Convolutional neural network for automated tooth segmentation on intraoral scans.

BACKGROUND: Tooth segmentation on intraoral scanned (IOS) data is a prerequisite for clinical applications in digital workflows. Current state-of-the-art methods lack the robustness to handle variability in dental conditions. This study aims to propose and evaluate the performance of a convolutional neural network (CNN) model for automatic tooth segmentation on IOS images. METHODS: A dataset of 761 IOS images (380 upper jaws, 381 lower jaws) was acquired using an intraoral scanner. The inclusion criteria included a full set of permanent teeth, teeth with orthodontic brackets, and partially edentulous dentition. A multi-step 3D U-Net pipeline was designed for automated tooth segmentation on IOS images. The model's performance was assessed in terms of time and accuracy. Additionally, the model was deployed on an online cloud-based platform, where a separate subsample of 18 IOS images was used to test the clinical applicability of the model by comparing three modes of segmentation: automated artificial intelligence-driven (A-AI), refined (R-AI), and semi-automatic (SA) segmentation. RESULTS: The average time for automated segmentation was 31.7 ± 8.1 s per jaw. The CNN model achieved an Intersection over Union (IoU) score of 91%, with the full set of teeth achieving the highest performance and the partially edentulous group scoring the lowest. In terms of clinical applicability, SA took an average of 860.4 s per case, whereas R-AI showed a 2.6-fold decrease in time (328.5 s). Furthermore, R-AI offered higher performance and reliability compared to SA, regardless of the dentition group. CONCLUSIONS: The 3D U-Net pipeline was accurate, efficient, and consistent for automatic tooth segmentation on IOS images. The online cloud-based platform could serve as a viable alternative for IOS segmentation.

Deep convolutional neural network-based automated segmentation and classification of teeth with orthodontic brackets on cone-beam computed-tomographic images: a validation study.

OBJECTIVE: Tooth segmentation and classification from cone-beam computed tomography (CBCT) is a prerequisite for diagnosis and treatment planning in the majority of digital dental workflows. However, an accurate and efficient segmentation of teeth in the presence of metal artefacts still remains a challenge. Therefore, the following study aimed to validate an automated deep convolutional neural network (CNN)-based tool for the segmentation and classification of teeth with orthodontic brackets on CBCT images. METHODS: A total of 215 CBCT scans (1780 teeth) were retrospectively collected, consisting of pre- and post-operative images of the patients who underwent combined orthodontic and orthognathic surgical treatment. All the scans were acquired with NewTom CBCT device. A complete dentition with orthodontic brackets and high-quality images were included. The dataset were randomly divided into three subsets with random allocation of all 32 tooth classes: training set (140 CBCT scans-400 teeth), validation set (35 CBCT scans-100 teeth), and test set (pre-operative: 25, post-operative: 15 = 40 CBCT scans-1280 teeth). A multiclass CNN-based tool was developed and its performance was assessed for automated segmentation and classification of teeth with brackets by comparison with a ground truth. RESULTS: The CNN model took 13.7 ± 1.2 s for the segmentation and classification of all the teeth on a single CBCT image. Overall, the segmentation performance was excellent with a high intersection over union (IoU) of 0.99. Anterior teeth showed a significantly lower IoU (P < 0.05) compared to premolar and molar teeth. The dice similarity coefficient score of anterior (0.99 ± 0.02) and premolar teeth (0.99 ± 0.10) in the pre-operative group was comparable to the post-operative group. The classification of teeth to the correct 32 classes had a high recall rate (99.9%) and precision (99%). CONCLUSIONS: The proposed CNN model outperformed other state-of-the-art algorithms in terms of accuracy and efficiency. It could act as a viable alternative for automatic segmentation and classification of teeth with brackets. CLINICAL SIGNIFICANCE: The proposed method could simplify the existing digital workflows of orthodontics, orthognathic surgery, restorative dentistry, and dental implantology by offering an accurate and efficient automated segmentation approach to clinicians, hence further enhancing the treatment predictability and outcomes.

Trueness of cone-beam computed tomography-derived skull models fabricated by different technology-based three-dimensional printers.

BACKGROUND: Three-dimensional (3D) printing is a novel innovation in the field of craniomaxillofacial surgery, however, a lack of evidence exists related to the comparison of the trueness of skull models fabricated using different technology-based printers belonging to different cost segments. METHODS: A study was performed to investigate the trueness of cone-beam computed tomography-derived skull models fabricated using different technology based on low-, medium-, and high-cost 3D printers. Following the segmentation of a patient's skull, the model was printed by: (i) a low-cost fused filament fabrication printer; (ii) a medium-cost stereolithography printer; and (iii) a high-cost material jetting printer. The fabricated models were later scanned by industrial computed tomography and superimposed onto the original reference virtual model by applying surface-based registration. A part comparison color-coded analysis was conducted for assessing the difference between the reference and scanned models. A one-way analysis of variance (ANOVA) with Bonferroni correction was applied for statistical analysis. RESULTS: The model printed with the low-cost fused filament fabrication printer showed the highest mean absolute error ([Formula: see text]), whereas both medium-cost stereolithography-based and the high-cost material jetting models had an overall similar dimensional error of [Formula: see text] and [Formula: see text], respectively. Overall, the models printed with medium- and high-cost printers showed a significantly ([Formula: see text]) lower error compared to the low-cost printer. CONCLUSIONS: Both stereolithography and material jetting based printers, belonging to the medium- and high-cost market segment, were able to replicate the skeletal anatomy with optimal trueness, which might be suitable for patient-specific treatment planning tasks in craniomaxillofacial surgery. In contrast, the low-cost fused filament fabrication printer could serve as a cost-effective alternative for anatomical education, and/or patient communication.

Postoperative complications following orthognathic surgery in patients with rheumatic diseases: A 2-year follow-up study.

OBJECTIVE: The purpose of this study was to describe the complications following orthognathic surgery in patients with rheumatic diseases and to evaluate rheumatic disease as a possible risk factor. METHODS: A retrospective cohort study was conducted during a 6-year period. The sample consisted of rheumatic and healthy patients who underwent orthognathic surgery. The outcome variables included infection, relapse, respiratory complications, hemorrhage, neurosensory disturbances, temporomandibular joint complications, and removal of osteosynthesis material. Bivariate analysis and logistic regression were applied to identify rheumatic disease as an independent risk factor for complications after orthognathic surgery. RESULTS: Twenty patients were identified as having rheumatic diseases (male: 2; female: 18; mean age: 37.8 ± 13.6 years), and 278 patients were systemically healthy (male: 105; female: 173; mean age: 25.8 ± 11.8 years). The most frequent complications in rheumatic and healthy patients were delayed recovery from neurosensory disturbance (55% and 33%), removal of osteosynthesis material (45% and 26%), and infection (35% and 7%). Following adjustment for possible confounders, rheumatic disease showed a significant association with infection (OR = 4.191, p = 0.016). CONCLUSION: Patients with rheumatic diseases are at a higher risk of postoperative infection following orthognathic surgery compared to healthy patients.

Validation of a 3D methodology for the evaluation and follow-up of secondary alveolar bone grafting in unilateral cleft lip and palate patients.

OBJECTIVE: The aim of the study was to propose and validate a method for three-dimensional (3D) quantitative assessment of secondary alveolar bone grafting (SABG) and its stability in time for patients with unilateral cleft lip and palate (UCLP). SETTINGS AND SAMPLE POPULATION: Ten non-syndromic UCLP patients (9 males and 1 female with a mean age of 9.5 ± 0.9 years) undergoing SABG with good quality preoperative, immediate postoperative (6 weeks) and 6 months postoperative Cone Beam Computed Tomography (CBCT) scans were selected. MATERIALS AND METHODS: The preoperative and 6 months postoperative scans were registered onto the immediate postoperative scan. The bone-grafted region was defined on the immediate postoperative scan and refined on the registered preoperative scan resulting in a 3D volume. The residual bone graft was calculated by applying threshold based segmentation on the registered 6 months postoperative scan within the segmented bone graft volume of the previous step. Inter and intra observer tests using intra-class correlation coefficient (ICC) were applied comparing the volumes of the 3D models. RESULTS: An excellent reliability was found for inter and intra observers with ICC ≥ 0.95. CONCLUSIONS: The presented method proved to be reliable for volumetric assessment of the alveolar bone graft in UCLP patients, as well as to assess the percentage of bone resorption during follow-up.

Long-term three-dimensional effects of orthognathic surgery on the pharyngeal airways: a prospective study in 128 healthy patients.

OBJECTIVE: To investigate volumetric and circumferential pharyngeal airway space (PAS) changes and stability over time as evaluated with cone beam computed tomography (CBCT) before and after orthognathic surgery 2 years postoperatively. MATERIALS AND METHODS: One hundred twenty-eight patients underwent bimaxillary orthognathic surgery at the Department of Maxillofacial Surgery of University Hospitals, Leuven, Belgium, were recruited prospectively. Patients were divided into 4 groups based on the amount of mandibular advancement in 5 mm increments (< 0 mm, 0-5 mm, 5-10 mm, or > 10 mm). CBCT data was acquired preoperatively and 1-6 weeks, 6 months, 1 year, and 2 years postoperatively. Patients with a history of maxillofacial trauma or surgery, obstructive sleep apnoea syndrome, or craniofacial anomalies were excluded. Nasopharyngeal, oropharyngeal, and hypopharyngeal PAS volumes and constriction surface areas (mCSA) were measured and compared between each time point with a paired t-test. RESULTS: The largest significant increase in oropharyngeal volume and mCSA were observed in the 5-10 mm (+ 13.3-21.7%, + 51.3-83.0%)) and > 10 mm (+ 23.3-44.6%, + 92.3-130.0%) mandibular advancement groups. This increase only remained stable 2 years postoperatively in the > 10 mm group. In other mandibular advancement groups, short-term oropharyngeal volume and mCSA increases were noticed, which returned to baseline levels 6 months to 1 year postoperatively. CONCLUSION: Bimaxillary advancement osteotomy significantly increases oropharyngeal volume and mCSA, which remains stable between 6 months to 1 year postoperatively. CLINICAL RELEVANCE: Long-term stable volumetric and mCSA enlargements were found with > 10 mm mandibular advancements over a period of 2 years. Return towards baseline levels was observed in the other mandibular advancement groups.

Quality and haptic feedback of three-dimensionally printed models for simulating dental implant surgery.

STATEMENT OF PROBLEM: A model offering anatomic replication and haptic feedback similar to that of real bone is essential for hands-on surgical dental implant training. Patient-specific skeletal models can be produced with 3-dimensional (3D) printing, but whether these models can offer optimal haptic feedback for simulating implant surgery is unknown. PURPOSE: The purpose of this trial was to compare the haptic feedback of different 3D-printed models for simulating dental implant surgery. MATERIAL AND METHODS: A cone beam computed tomography image of a 60-year-old man with a partially edentulous mandible was manipulated to segment the mandible and isolated from the rest of the scan. Three-dimensional models were printed with 6 different printers and materials: material jetting-based printer (MJ, acrylic-based resin); digital light processing-based printer (DLP, acrylic-based resin); fused filament fabrication-based printer (FFF1, polycarbonate filament; FFF2, polylactic acid filament); stereolithography-based printer (SLA, acrylic-based resin); and selective laser sintering-based printer (SLS, polyamide filament). Five experienced maxillofacial surgeons performed a simulated implant surgery on the models. A 5-point Likert scale questionnaire was established to assess the haptic feedback. The Friedman test and cumulative logit models were applied to evaluate differences among the models (α=.05). RESULTS: The median score for drilling perception and implant insertion was highest for the MJ-based model and lowest for the SLS-based model. In relation to the drill chips, a median score of ≥3 was observed for all models. The score for corticotrabecular transition was highest for the MJ-based model and lowest for the FFF2-based model. Overall, the MJ-based model offered the highest score compared with the other models. CONCLUSIONS: The 3D-printed model with MJ technology and acrylic-based resin provided the best haptic feedback for performing implant surgery. However, none of the models were able to completely replicate the haptic perception of real bone.

Survival and success of autotransplanted impacted maxillary canines during short-term follow-up: A prospective case-control study.

OBJECTIVES: This prospective clinical trial aimed to examine the predictability of maxillary canine transplantation as compared to biological canine eruption. Additional objectives were to examine hard and soft tissue outcomes, including aesthetic outcome compared to outcomes with the contralateral canines. SETTINGS AND SAMPLE POPULATION: The sample comprised 17 consecutively transplanted maxillary canines in 17 patients (mean age at surgery, 18 years; range, 11-29 years). Minimal follow-up time was 12 months post-transplantation. Clinical and radiographic parameters were recorded for the transplanted and contralateral canines, showing a natural eruption pattern. MATERIAL AND METHODS: The Maxillary Canine Aesthetic Index (MCAI) and the Autotransplanted Maxillary Canine Radiological Index (AMCRI) were scored for all upper canines. Successful transplantation was considered as the absence of pathology during intermittent clinical and radiographic controls and a good-to-excellent outcome compared to the contralateral biological erupted canine, as defined by the MCAI and AMCRI. RESULTS: The mean follow-up period was 28 months (±9; range, 12-40 months). The overall survival rate was 100%, and the success rate reached 68% at 1 year post-operatively. Significant predictors of success were the extra-oral time during transplantation, amount of damage to the root surface, quality of surrounding tissues and immediate post-operative oral hygiene. CONCLUSION: Standardized measurements demonstrated clinically satisfactory outcomes with maxillary canine autotransplantation compared to outcomes with the contralateral canine during 1-3 years of follow-up. The potential predictors of success identified here should be confirmed with long-term follow-up studies.

Complications Following One-Stage Versus Two-Stage Surgical Treatment of Transverse Maxillary Hypoplasia.

PURPOSE: Contemporary literature suggests a similar transverse stability of a surgical-assisted rapid palatal expansion and a segmented Le Fort I osteotomy. The aim of this study was to compare postoperative complications of 1-stage (segmental maxillary osteotomy) and 2-stage (surgical-assisted rapid palatal expansion followed by Le Fort I osteotomy) treated patients to determine the preferred treatment strategy. MATERIALS AND METHODS: This retrospective study included 74 consecutive patients (age range: 14 - 57 years; 36 males, 38 females) with a moderate transverse maxillary hypoplasia: 32 patients were treated in a 1-stage protocol and 42 in a 2-stage protocol with a postoperative follow-up of at least 1 year. Dental complications such as loss of teeth, gingival dehiscence, periodontal bone loss, apical root resorption, and surgical complications such as pain, hemorrhage, altered neurosensitivity, wound infection, aseptic necrosis were analyzed. Univariate analysis consisted of a generalized linear model with logit link or Fisher exact test. RESULTS: No significant difference was found for group characteristics except for longer orthodontic treatment time in the 2-stage group. Incidence and severity of complications were comparable for the 1-stage and 2-stage patients. Only overall pain was significantly greater in the 2-stage patient group (P = .038). CONCLUSIONS: Considering a similar complication rate and transversal stability, the choice between 1-stage and 2-stage approach for patients with a moderate transverse maxillary hypoplasia should be patient specific.

Accuracy of cone beam computed tomography-derived casts: A comparative study.

STATEMENT OF PROBLEM: The accuracy of the external surface and internal trabecular architecture of large cone beam computed tomography (CBCT)-derived dentomaxillofacial anatomic casts has not yet been thoroughly investigated. PURPOSE: The purpose of this comparative study was to evaluate the quantitative accuracy of CBCT-derived mandibular casts by applying an innovative land-mark free methodology. MATERIAL AND METHODS: Following inclusion and exclusion criteria, a CBCT scan of an 18-year-old woman was acquired. The mandible was segmented and isolated from the data set. The segmented mandible included depiction of the cortical surface, trabecular architecture, erupted teeth, and impacted third molars with incomplete root formation. Fifteen mandibular casts were fabricated by using multijet (MJ=4), digital light processing (DLP=4), stereolithography (SLA=2), fused deposition modeling (FDM=2), colorjet (CJ=2), and selective laser sintering (LS=1)-based high-quality medical commercial and office printers. Each printed cast was scanned and superimposed onto the original mandible, and the accuracy of the complete mandible and individual surfaces were assessed with a color-coded map. RESULTS: When the overall combined error associated with complete casts based on printing technology were compared, MJ showed the highest accuracy (0.6 ±0.7 mm). FDM technology (2.2 ±3.4 mm) had the highest overall absolute mean difference. No significant difference was observed when both individual surfaces and the complete mandible were compared. CONCLUSIONS: Overall, casts replicated the skeletal and dental anatomic surfaces well. However, shortcomings were observed in relation to depicting trabecular architecture.

Long-term dental stability after orthognathic surgery: a systematic review.

BACKGROUND: Long-term dental stability is one of the main objectives following combined orthodontic and orthognathic surgical treatment. It is influenced by multiple factors such as surgical, patient-related, and orthodontic aspects. While recent reviews mainly focus on short-term dental changes (0.5-2 years), longer follow-up dental stability remains hardly reviewed. OBJECTIVES: The aim of this study was to evaluate long-term stability of dental and dentolabial changes following combined orthodontic and orthognathic surgical treatment with a minimum follow-up period of 5 years. SEARCH METHODS: A systematic search was conducted up to December 2019 using Pubmed, Embase, Web of Science, and Cochrane Central. SELECTION CRITERIA: Randomized controlled trials (RCTs), prospective and retrospective cohort studies, and case series with a minimum of 10 patients, which reported long-term dental stability following combined orthodontic and orthognathic treatment, were included. DATA COLLECTION AND ANALYSIS: Long-term changes were assessed for overjet, overbite, maxillary, and mandibular incisors' position and relationship of lip position to maxillary and mandibular incisors. Risk of bias was assessed according to the Cochrane Handbook. RESULTS: Following the screening of 3178 articles, 11 studies were included (2 RCT, 9 retrospective) with a postoperative follow-up period ranging from 5 to 15 years. A decrease in overjet was observed for patients with skeletal class III malocclusion, whereas overjet increased in class II patients at long-term follow-up. Overbite increased in class II patients, whereas class III showed variable results. The lower incisor position was more stable vertically than horizontally; the latter showing more outcome variability. Dentolabial changes corresponded to the normal ageing process and results were not clinically significant after long-term follow-up. CONCLUSION: Current evidence suggests variability of dental and dentolabial stability in both skeletal class II and III patients. Further prospective studies are required to develop guidelines for long-term follow-up assessment using computer tomography or cone-beam computed tomography imaging, before final conclusions can be drawn. REGISTRATION: The protocol for this systematic review (CRD42020133844) was registered in the International Prospective Register of Systematic Reviews (PROSPERO).

Three-dimensional characterisation of the globe position in the orbit.

PURPOSE: Current methods to analyse the globe position, including Hertel exophthalmometry and computed tomography (CT), are limited to the axial plane and require the lateral orbital rim and cornea as landmarks. This pilot study aimed to design a method to measure the position of the globe in the axial, coronal and sagittal plane and independent from orbital bony and corneal references. METHODS: With the aid of three-dimensional CT reconstruction technology, we determined the globe position in the orbit based on the centre of the globe. Method validation was performed using data of consecutive orbital CT scans from the control group and from the patients with Graves' orbitopathy who underwent orbital decompression surgery with removal of the lateral orbital margin. RESULTS: The inter- and intra-observer reliability was excellent with a high intraclass correlation coefficient (> 0.99, 95% CI [0.97; 1.00]). In the decompressed orbits, there was a statistically significant globe position shift along the anterior-posterior axis (P = 0.0005, 95% CI [0.63; 3.66]), but not along the medial-lateral and superior-inferior axis. CONCLUSION: The 3D CT method can accurately and reliably characterise the globe position shift in the three dimensions without using orbital and corneal anatomical landmarks. The method can be useful to determine the globe shift in proptosis, enophthalmos, hypoglobus and hyperglobus, even in the presence of strabismus and orbital bone defects.

Trueness of cone beam computed tomography versus intra-oral scanner derived three-dimensional digital models: An ex vivo study.

OBJECTIVES: To compare the trueness of 3D digital models derived from CBCT and IOS and to evaluate their accuracy for implementation in oral implant rehabilitation. MATERIALS AND METHODS: A dry human mandible with a full set of intact teeth was included in the study. The mandible was scanned using Trios IOS and four different CBCT machines with various protocols for generation of 3D digital models. A µCT was utilized to scan each tooth individually. Following registration and segmentation, the trueness evaluation of 3D digital models was carried out by part comparison analysis and color-coded mapping of the superimposed teeth surfaces. RESULTS: The four CBCT-derived 3D digital models with different protocols had better trueness than Trios IOS. NewTom VGi evo (110 KV), ProMax 3D (90 kV), 3D Accuitomo 170 (90 kV), Green 21 (110 kV), and Green 21 (90 kV) showed significantly better trueness than IOS. However, 3D Accuitomo 170 and ProMax 3D CBCT devices with 70 kV protocol showed better trueness without any significant difference with IOS. CONCLUSION: CBCT-derived 3D digital models showed better trueness when compared with IOS. When CBCT data are available for preoperative planning for oral implant rehabilitation, it may preclude the need for IOS for obtaining 3D study models.

Comparative evaluation of cone beam CT and micro-CT on blooming artifacts in human teeth filled with bioceramic sealers.

AIM: To assess blooming artifacts caused by root canal sealers in CBCT images compared with those that appeared in micro-CT scan images used as references. MATERIALS AND METHOD: Thirty freshly extracted human mandibular central incisors were used. Root canals were prepared with nickel titanium files with an ISO size 40/0.06 taper and filled with a single cone (40/0.06 taper) and three different sealers. The samples were divided into the following three groups with 10 roots each: (I) AH Plus sealer; (II) Sure Seal Root; and (III) Total BC sealer. Teeth were scanned with the same voxel sizes (0.2 mm) in different CBCT devices and the micro-CT images were acquired as reference images. RESULTS: Significantly different results in terms of blooming artifacts were detected between CBCT and micro-CT images, as well as among the CBCTs images. The canals filled with AH Plus sealer showed more blooming artifacts than those filled with bioceramic sealers (p < 0.05). Additionally, the worst blooming artifact was observed when the images were acquired with lower kilovoltage peak. CONCLUSION: The appearance of blooming artifacts is dependent on sealer and CBCT, and their effects are significantly worse than they are in micro-CT images. The differential effect of different sealers and distinct CBCT protocols should be further investigated to enable the use of bioceramic sealers without a significant impact on post-treatment imaging. CLINICAL RELEVANCE: Root canal sealers showed a different extent of blooming artifact in CBCT images. Hence, researchers and clinicians should be aware of these artifacts before conducting endodontic evaluations using CBCT images.

Surgical Management of an Aggressive Multifocal Squamous Odontogenic Tumor.

Squamous odontogenic tumor is a rare benign epithelial odontogenic tumor of the jaw. Most are solitary lesions, although rare multifocal lesions have been described. Maxillary lesions have more aggressive behavior. Because of their benign character, these lesions are usually treated using a conservative surgical approach with curettage and surgical enucleation. This report describes the case of a 29-year-old woman with multifocal lesions who was initially treated with conservative surgical therapy. Early recurrence 6 months after surgery prompted more aggressive resection. This case is discussed in the context of current evidence related to the epidemiology, etiology, diagnosis, and therapy of squamous odontogenic tumors.

Improved Interobserver Reliability of the Sanders Classification in Calcaneal Fractures Using Segmented Three-Dimensional Prints.

We examined the added value of 3-dimensional (3D) prints in improving the interobserver reliability of the Sanders classification of displaced intraarticular calcaneal fractures. Twenty-four observers (radiologists, trainees, and foot surgeons) were asked to rate 2-dimensional (2D) computed tomography images and 3D prints of a series of 11 fractures, selected from cases treatment at our level I trauma center between 2014 and 2016. The interobserver reliability for the Sanders classification was assessed using kappa coefficients. Three versions of the Sanders classification were considered: Sanders classification with subclasses, Sanders classification without subclasses, and the combination of Sanders types III and IV because of the high incidence of comminution in both types. The reference standard for classification was the perioperative findings by a single surgeon. The 3D print always yielded higher values for agreement and chance-corrected agreement. The Brennan-Prediger-weighted kappa equaled 0.35 for the 2D views and 0.63 for the 3D prints for the Sanders classification with subclasses (p = .004), 0.55 (2D) and 0.76 (3D) for the classification without subclasses (p = .003), and 0.58 (2D) and 0.78 (3D) for the fusion of Sanders types III and IV (p = .027). Greater agreement was also found between the perioperative evaluation and the 3D prints (88% versus 65% for the 2D views; p < .0001). However, a greater percentage of Sanders type III-IV were classified with 2D than with 3D (56% versus 32%; p < .0001). The interobserver agreement for the evaluation of calcaneal fractures was improved with the use of 3D prints after "digital disarticulation."

A novel in vivo method to evaluate trueness of digital impressions.

BACKGROUND: Intraoral scanners are devices for capturing digital impressions in dentistry. Until now, several in vitro studies have assessed the trueness of digital impressions, but in vivo studies are missing. Therefore, the purpose of this study was to introduce a new method to assess trueness of intraoral scanners and digital impressions in an in vivo clinical set-up. METHODS: A digital impression using an intraoral scanner (Trios® 3 Cart wired, 3Shape, Copenhagen, Denmark) and a conventional alginate impression (Cavex Impressional®, Cavex, Haarlem, the Netherlands) as clinical reference were made for two patients assigned for full mouth extraction. A total of 30 teeth were collected upon surgery after impressions making. The gypsum model created from conventional impression and extracted teeth were then scanned in a lab scanner (Activity 885®, SmartOptics, Bochum, Germany). Digital model of the intraoral scanner (DM), digital model of the conventional gypsum cast (CM) and those of the extracted natural teeth (NT) were imported to a reverse engineering software (3-matic®, Materialise, Leuven, Belgium) in which the three models were registered then DM and CM were compared to their corresponding teeth in NT by distance map calculations. RESULTS: DM had statistically insignificant better trueness when compared to CM for total dataset (p = 0.15), statistically insignificant better trueness for CM when mandibular arches analyzed alone (p = 0.56), while a significantly better DM trueness (p = 0.013) was found when only maxillary arches were compared. CONCLUSIONS: Our results show that digital impression technique is clinically as good as or better than the current reference standard for study models of orthognathic surgery patients.

Pharmacists' knowledge of issues in pharmacotherapy of epilepsy using antiepileptic drugs: A cross-sectional study in Palestinian pharmacy practice.

OBJECTIVE: Antiepileptic drugs (AEDs) are mainstay in controlling epileptic seizures. As experts in medications, pharmacists should be able to ensure accuracy of dosing regimens, explain adverse effects, and screen for and alert people with epilepsy (PWE) and their physicians to possible drug-drug interactions (DDIs). The aim of this study was to evaluate pharmacists' knowledge of issues in pharmacotherapy of epilepsy using AEDs. METHODS: This was a cross-sectional observational study conducted in the Palestinian pharmacy practice. A 10-item case-based questionnaire was used to determine actions taken by pharmacists in theoretical situations in pharmacotherapy of epilepsy. Demographic and practice details of the study participants were also collected. Scores were calculated as percentage of correct answers for each participant. RESULTS: The number of participants was 394. The majority (approximately 75%) identified themselves as community pharmacists. The median score was 33.4% with an IQR of 33.3. Pharmacists who received training on epilepsy and AEDs during their pharmacy degree program were 4.78-fold (95% C.I. of 1.82-12.60) more likely to score ≥50% in the test than those who did not receive training on epilepsy and AEDs. Despite gaps in knowledge, pharmacists tended to perform the necessary action in cases of adverse effects and aggravated seizures associated with AEDs. CONCLUSION: Pharmacists can play a crucial role in providing essential information on AEDs to patients and prescribers. There are many knowledge gaps that need to be filled. Specifically designed pedagogic and/or training interventions might be helpful in filling these gaps.