Investigation of the extent of post-extraction bone contraction and bone remodeling after 4 months. A prospective pilot study.

OBJECTIVES: Aim was to investigate a correlation between the serum levels of 25(OH)D and the resorption of the alveolar bone walls and regeneration of the alveolar space after tooth extractions. METHODS: 14 adults in need of extraction of hopeless teeth were enrolled. An intraoral digital impression was performed using CS3600 scanner, and each patient was tested to assess serum vitamin D levels. Subsequently, extraction of teeth and contextual guided bone regeneration was performed using porcine origin graft material and a resorbable collagen membrane to covert the defect. After 4 months, an impression was taken, and the model was scanned using a professional scanner for lab. At the same time, a CBCT exam was performed to perform implant insertion through fully digital computer guided surgery. Bone was collected to perform histological and histomorphometric analysis. Pre and postoperative scans were compared using a specific software GOM Inspect, GOM GmbH, Germany) to estimate the volumetric changes. GLM tests were applied to investigate the relationship between the different predictor variables and the outcome variables. RESULTS: 14 patients were divided in 3 groups depending on the serum Vit-D levels, identifying three ranges corresponding to low (lower than 20), medium (between 20-30), and optimal vitamin D levels (higher than 30). Volumetric contraction after extraction was observed for all patients without any significant difference. Focusing on the post-extraction regeneration, patients belonging to the group with lower levels of Vit-D displayed lower and more disorganized levels of bone. Immunohistochemistry analysis showed that Col1A1 and Osteocalcin had no physiological alteration. Osteopontin could be identified near the external surface of bone tissue granules. Runx2 signals were detected near the margins of bone trabeculae. CONCLUSIONS: Serum vit-D levels do not appear to influence the extent of post-extraction bone contraction. On the contrary, it seems to significantly influence the post-extraction regeneration. CLINICAL SIGNIFICANCE: Vit D serum levels may influence the regenerative aspect during post-extraction turn-over. This might suggest controlling and (in case of low levels) recommend Vit D supplement in the patient diet in case of extraction.

Bitemark analysis comparing the use of digital scans and 3D resin casts.

Although dental patterns are unique, the use of bitemark analysis in personal identification remains controversial. To accurately reproduce and compare three-dimensional models of bitemarks and dental arches, intraoral three-dimensional scans, commonly utilized in clinical dental practice for precise and stable digital impressions, are recommended. This study aims to compare two different techniques for bitemark analysis: a digital method based on the superimposition of digital scans of dental patterns and lesions, and a visual method based on the physical superimposition of impressions and resin casts produced by 3D printing. A sample of 12 volunteers (6 males and 6 females) with a mean age of 26 years was collected as biters. Each subject was asked to bite on custom supports made from semi-rigid water bottles covered with imprintable dental wax. The dental arches and bitemarks were then recorded using an intraoral scanner and dental impressions. Scan superimposition analysis was conducted using CloudCompare software, while resin casts were printed using a 3D printer and physically superimposed on the bitemark impressions by a blind operator, who was not involved in sample collection, bite test execution, prior cast acquisition, or CloudCompare analysis. Both superimposition techniques relied on the selection of 10 corresponding landmarks (on canines and central and lateral incisors of the upper and lower arches) between the dental arches and impressions. The digital superimposition showed an average concordance of 92.5% for the upper arch landmarks and 85% for the lower arch landmarks, with an overall average concordance of 88.8% for both arches combined. In contrast, the visual analysis of resin casts showed an average concordance of 77.5% for the upper arch and 76.7% for the lower arch, with an overall average of 77.1% for both arches combined. In the analysis performed using CloudCompare, the maxillary arch demonstrated the best superimposition, with 4 landmarks (R0, R1, R2, R5) consistently overlapping. The digital analysis outperformed the visual analysis in all four quadrants, particularly in the upper right arch compared to the lower left arch, thereby supporting the integration of digital techniques in forensic applications. Further studies are necessary to validate the digital technique on a larger sample, including subjects with different dental characteristics, bite dynamics, and varying types of supports and substrates.

Application of digital workflow and technologies in clinical paediatric dentistry: a scoping review.

PURPOSE: The purpose of the present scoping review is to map the literature reporting on the application of digital workflows and digital technologies in the diagnosis, treatment, or management of dental conditions in paediatric patients. Furthermore, the review focuses on identifying possible knowledge gaps in the area and developing specific recommendations for future investigations. METHODS: An electronic search was performed on 3 databases up to July 2023. After the authors independently screened the retrieved articles, they extracted the data and assessed the risk of bias using the JBI (The Joanna Briggs Institute) critical appraisal tools and the Cochrane Risk of Bias 1 tool, depending on the study design assessed. RESULTS: After full-text assessment, 58 studies were identified that met the inclusion and exclusion criteria. The results were divided into two groups according to the study design: 36 were research articles, and 22 were case reports; only the research articles were included in the qualitative synthesis. The most common topic was Scanners/3 d digital model analysis (11 articles), followed by Digital Imaging (8 articles). Digital applications were also a popular topic, and tele-dentistry and artificial intelligence were also present in the included studies. CONCLUSION: Studies investigating the use of digital workflows and digital technologies in the diagnosis, treatment or management of dental conditions in paediatric dentistry are lacking. In general, future investigations should be based on higher quality studies; furthermore, the lack of studies on the clinical validation of digitally fabricated orthodontic devices and restorations in paediatric patients provides insights for future research.

Recording maximal intercuspation and border positions of the mandible with intraoral scanner using the acquisition software's multi-occlusion function.

PURPOSE: This in vitro study was conducted to investigate the accuracy of intraoral scanner (IOS) for recording maximal intercuspal position (MIP) and border positions of the mandible. MATERIALS AND METHODS: Maxillary and mandibular master casts were articulated in MIP, protrusive, and lateral interocclusal position sequentially on a semi-adjustable articulator. For each articulation relation, sites of occlusal contacts (SOCs) and sites of clearance (SCs) were identified on the master casts with articulating paper (reference sites). IOS was used to take full arch scans and nine virtual interocclusal records (VIRs) for virtual articulation of models. Virtual SOCs and SCs were detected with 3D processing software and compared to those identified with the articulating paper. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each articulation relation. RESULTS: For MIP, IOS showed adequate sensitivity and NPV of 100%, and specificity and a PPV of 99%. For protrusive position, the IOS showed a sensitivity and a NPV of 100%, a high PPV of 86%, and a specificity of 83%. For lateral positions, the specificity and the PPV were high (93% and 79%, respectively), but the sensitivity and the NPV were below the clinically acceptable limits (28% and 56%, respectively). CONCLUSION: IOS displayed clinically acceptable accuracy for recording MIP and protrusive border mandibular position. However, IOS had less accuracy for lateral border mandibular position.

Effect of cut-out rescanning protocol on the accuracy of digital impressions in convergent implants positioned at varying depths: An in vitro study.

BACKGROUND: This study aimed to assess the effect of the "cut-out rescan" strategy on the accuracy of intraoral digital scans from 25° convergent implants positioned at two distinct depths. MATERIAL AND METHODS: Two customized models were fabricated, each designated to receive two posterior converged implant fixtures: one at a depth of 1 mm and the other at a depth of 4 mm. Initially, the models were scanned as reference casts using a lab scanner. The test group was involved in scanning the 1-mm and 4-mm implant models using an intraoral scanner in the following order: (1) scanning the 1-mm (T1; n=10) and (2) 4-mm (T4; n=10) implant groups with scan bodies connected to both fixtures in each model; (3) cut-out rescan (COR) in the 1-mm (COR1; n=10) and (4) 4-mm (COR4; n=10) models, leading to 40 digital files in standard tessellation language format. The mean absolute deviation (MAD), in terms of trueness and precision, between the experimental and control scans was assessed through the alignment of their respective datasets using three-dimensional analysis software. Two-way analysis of variance (ANOVA) and Levene's tests were used to analyze the data. RESULTS: The COR4 group exhibited the highest MAD, indicative of both trueness and precision (Mean ±SD: 55.659 ±34.802). In contrast, the T1 group demonstrated the lowest MAD (Mean ±SD: 43.225 ±19.237). However, the ANOVA analysis showed no significant influence of depth (P=0.506) or type of scan (P=0.442) on the MAD. Precision also did not differ significantly across groups (P=0.071). CONCLUSIONS: The cut-out rescan approach demonstrated an accuracy comparable to that of the one-time scan method. CLINICAL SIGNIFICANCE: Digital intraoral scanning provides clinicians with a range of tools to navigate challenging conditions in which conventional methods may prove difficult, such as cases involving angled adjacent implants. In these scenarios, the cut-out rescan tool serves as a valuable resource, aiding clinicians in overcoming the challenges associated with impression-making owing to the convergence of placed implants.

Evaluating the accuracy of CEREC intraoral scanners for inlay restorations: impact of adjacent tooth materials.

BACKGROUND: The accuracy of intraoral scanning is critical for computer-aided design/computer-aided manufacturing workflows in dentistry. However, data regarding the scanning accuracy of various adjacent restorative materials and intraoral scanners are lacking. This in vitro study aimed to evaluate the effect of adjacent restorative material type and CEREC's intraoral scanners on the accuracy of intraoral digital impressions for inlay cavities. METHODS: The artificial tooth was prepared with an occlusal cavity depth of 2 mm, a proximal box width at the gingival floor of 1.5 mm, and an equi-gingival margin extended disto-occlusally at the transition line angle on both the lingual and buccal sides for an inlay restoration. The adjacent teeth were veneered with crowns made of gold and zirconia, and an artificial tooth (resin) was utilized as the control group. The inlay cavity and adjacent teeth (Gold, Zirconia, and resin) were scanned 10 times using Chairside Economical Restoration of Esthetic Ceramics (CEREC) Primescan (PS), Omnicam (OC), and Bluecam (BC). A reference scan was obtained using a laboratory scanner (3-shape E3). Scanning was performed according to the manufacturer's instructions, including powder application for the BC group. Standard tesselation language files were analyzed using a three-dimensional analysis software program. Experimental data were analyzed using a two-way analysis of variance and the Tukey's post-hoc comparison test. RESULTS: The restorative materials of the adjacent teeth significantly affected the accuracy of the intraoral digital impressions (p < .05). The zirconia group exhibited the highest trueness deviation, followed by the resin and gold groups, with each demonstrating a statistically significant difference (p < .05). The resin group demonstrated the highest maximum positive deviation and deviation in precision. Gold exhibited the lowest average deviation value for trueness compared with those of the other adjacent restorative materials. Intraoral scanner type significantly influenced the trueness and precision of the scan data (p < .05). The average deviation of trueness according to the intraoral scanner type increased in the following order: BC > PS > OC. The average deviation in precision increased in the following order: PS>OC>BC (p < .05). CONCLUSION: The restorative materials of the adjacent tooth and the type of intraoral scanner affect the accuracy of the intraoral digital impression. The trueness of the digital images of the BC group, obtained by spraying the powder, was comparable to that of the PS group. Among the adjacent restorative materials, zirconia exhibited the lowest trueness. In contrast, PS demonstrated the highest precision among the intraoral scanners, while resin displayed the lowest precision among the adjacent restorative materials.

Deviation Parameters of Intraoral Scanning with and without Artificial Markers versus Conventional Impression of Total, Partial and Congenital Nasal Defects: A Pilot Non-Randomized Clinical Trial.

PURPOSE: This pilot clinical trial aimed to investigate accuracy of intra-oral scanning (IOS) with and without artificial reference markers in capturing total, subtotal and congenital nasal defects. BASIC PROCEDURES: Thirteen patients with 3 types of nasal defects were selected and digitally scanned using an IOS with (ScM) and without artificial markers (Sc). Patients were grouped as follows; Group T (total nasal defect), Group P (partial/subtotal nasal defect), Group C (congenital defect). Silicone impressions of the defects were made and poured to get a model that was scanned using a Desktop scanner (Imp). The standard tessellation language (STL) files obtained from IOS were registered and compared to each other using a processing software. RMS, positive and negative average values were used to report deviations between the scans. Kruskal Wallis test was used to study the effect of defect type, while Friedmann was used to study the effect of impression technique. Results were considered significant at P≤.05. MAIN FINDINGS: All deviation values showed statistically significant differences among the 3 studied nasal defects and among the 3 investigated impression techniques. The smallest deviation values were recorded in Sc-ScM of congenital defects (RMS= 0.13±0.04, +average=0.08±0.01, -average=-0.09±0.02), while the largest deviation values were recorded in IMP-Sc in the total defects (RMS= 0.38±0.05, +average=0.29±0.04, -average=-0.29±0.04). CONCLUSIONS: Within the limitations of this study, it was concluded that the nasal defect type and the use of artificial markers during scanning affect the deviation parameters of the obtained scan. The combined effect of the studied parameters calls for the use of markers in when scanning total nasal defects.

Evaluation of hypermobile teeth deviation during impression taking in a partially edentulous dental arch: An in vitro study comparing digital and conventional impression techniques.

PURPOSE: This study aimed to compare the deviation of hypermobile teeth in partially edentulous dental arches during impression taking using digital and conventional techniques. METHODS: A partially edentulous mandibular model with three target hypermobile teeth (including the left first premolar, #34; left second molar, #37; and right first premolar, #44), was used as the simulation model. After reference data were acquired using a desktop scanner, impressions of the simulation model were obtained using a digital intraoral scanner (IOS) and two conventional techniques (hydrocolloid material with a stock tray and silicone material with a custom tray as impression data (n=12/group). The three-dimensional accuracy (root mean square value) and two-dimensional accuracy (mesiodistal and buccolingual displacements) of the target teeth in each impression dataset were calculated based on the reference data. The comparison among three impression techniques was statistically performed using the Kruskal-Wallis test (α=0.05). RESULTS: For #34 and #44, the three- and two-dimensional accuracies of the impressions fabricated through data acquired through digital scanning (digital impression) were significantly superior to those of the hydrocolloid impression (P < 0.05), whereas no significant difference was found between the digital and silicone impressions. For #37, no significant difference in the accuracy of the impression data for the target teeth was observed among the three impression techniques. CONCLUSIONS: Digital impression acquiring using an IOS is recommended over using a conventional hydrocolloid impression to prevent the deviation of hypermobile teeth in partially edentulous dental arches. Hypermobile tooth deviation in digital impression data depends on the tooth location.

Seismic analysis of Islamic Egyptian minarets through 3D scanning and dynamic simulation.

Recently, Egypt had seismic activity. These seismic events have affected the stability of minarets, especially historical ones. Weight is one of the minaret's main stability factors. The main objective of the current research is to perform a three-dimensional (3D) assessment of an existing minaret, determine its accurate spatial model, document its current condition, examine its stability in the event of earthquakes, and identify the requisite measures to safeguard the minaret from any potential damage. The masonry to construct the minaret was used by extracting and examining specimens of this substance to determine its physical characteristics. The current work created three-dimensional models of the Abou-Ghanam El-Bialy minaret using a terrestrial laser scanner (TLS) to document its current condition, as well as minaret was subjected to a free vibration analysis using 3D finite element modeling. Finally, the minaret's seismic behavior was assessed utilizing mode forms, base responses, and normal stresses. The surveying method effectively documented the Minarets' existing case. The 3D seismic analysis showed that the minaret responded dynamically to earthquake loading, with mode shapes, base reactions, and normal stresses being crucial characteristics. Based on these data, we may suggest procedures to protect the minaret during seismic events.

Insights into Occlusal Analysis: Articulating Paper versus Digital Devices.

Background: As the demand for digital dentistry constantly increases, digital devices are gradually replacing conventional methods of recording occlusal contacts. The study aimed to assess the inter-rater reliability of occlusal contact point detection using 40 µm articulating paper, Medit i700, and OccluSense and to compare the distribution of occlusal contacts using the articulating paper and intraoral scanner. Material and Methods: The study included 25 participants aged 20 to 30 (13 women and 12 men). Photographs of contact points were taken and marked in maximum intercuspal position (MIP), in protrusive and laterotrusive movements, on working and non-working sides using 40 µm articulating paper and digital devices. The Cohen's Kappa coefficient assessed the inter-rater reliability. The Wilcoxon signed-rank test was used to compare dependent groups, articulating paper, and Medit i700. Results: The Cohen's Kappa index showed that almost perfect agreement was achieved with 40 µm articulating paper. Compared to Medit i700, the 40 µm articulating paper showed an increased mean number of contacts per tooth, except for the third molars. Conclusions: The 40 µm articulating paper has detected more overall contacts than the digital devices, particularly in the posterior areas. An ideal method for registering occlusal contacts has not been established yet.

Automated Quantitative Image-Derived Input Function for the Estimation of Cerebral Blood Flow Using Oxygen-15-Labelled Water on a Long-Axial Field-of-View PET/CT Scanner.

The accurate estimation of the tracer arterial blood concentration is crucial for reliable quantitative kinetic analysis in PET. In the current work, we demonstrate the automatic extraction of an image-derived input function (IDIF) from a CT AI-based aorta segmentation subsequently resliced to a dynamic PET series acquired on a Siemens Vision Quadra long-axial field of view scanner in 10 human subjects scanned with [15O]H2O. We demonstrate that the extracted IDIF is quantitative and in excellent agreement with a delay- and dispersion-corrected sampled arterial input function (AIF). Perfusion maps in the brain are calculated and compared from the IDIF and AIF, respectively, showed a high degree of correlation. The results demonstrate the possibility of defining a quantitatively correct IDIF compared with AIFs from the new-generation high-sensitivity and high-time-resolution long-axial field-of-view PET/CT scanners.

A faster CO2 fractional scanner system mode for skin rejuvenation. A clinical study.

BACKGROUND: The market requires ever-faster techniques, in particular for pre-rejuvenation condition. AIM: The purpose of this study was to assess if a fractional CO2 scanner modality (called moveo) results in a faster full-face rejuvenation treatment in comparison to the standard mode, currently existing in the scanner system. MATERIALS AND METHODS: A total of 12 female patients affected by fine lines participated in a split-face clinical investigation and underwent to two sessions with a fractional CO2 laser system equipped with an existing and a faster dedicated scanner units. Pain was assessed using VAS. Three-dimensional clinical photographs were captured before, immediately after, 3 days, 14 days after the first treatment and immediately after the second treatment and 1 months after the last one. The uniformity and aesthetic coverage of treatments were assessed using dermatoscopy. Global aesthetic improvement scale (GAIS) was used. The time taken to treat the two sides of the face and all possible side effects were monitored. RESULTS: Following only two treatment session with both scanner modes, the patient's skin texture improved significantly, with fine lines reduction. There is no statistically significant difference in perceived pain between patients. The GAIS score showed satisfactory results following both modalities. The time parameters indicated that with the faster scanner mode the full-face treatment time was reduced by 30% compared to the standard one. No adverse effects were observed. CONCLUSIONS: The moveo modality provide faster treatment and a better final dermal aesthetic outcome than the standard procedure while maintaining the same safety profile.

Clinical, radiological and dynamic CT results of scapholunate intercarpal ligamentoplasty for scapholunate dissociation.

A clinical, radiological and four-dimensional computed tomography (4DCT) assessment of the outcomes of scapholunate intercarpal ligamentoplasty (SLICL) was done with a minimum follow-up of 2 years. Twenty-nine patients (23 men and 6 women) with a mean age of 40 years (22-57) who had chronic scapholunate dissociation were treated with the SLICL procedure. There were 18 cases of dynamic instability and 11 of static instability. The patients were evaluated with a mean follow-up of 61 months (24-94). SLICL significantly reduced pain and increased grip strength and wrist function. On radiographs, the mean static and dynamic scapholunate gaps as well as the scapholunate and radiolunate angles improved significantly. The dorsal scaphoid displacement was always corrected. 4DCT after surgery provided a more precise analysis of the SLICL's effectiveness at restoring intracarpal alignment. Correction of the DISI deformity and dorsal scaphoid displacement was confirmed. SLICL restored a normal variation in the scapholunate gap (range value) during radioulnar deviation movement without systematically reducing the distance between the bones (mean and maximum values) which remained pathological in wrists with static instability but not in those with dynamic instability. At the final follow-up, no patients had signs of osteoarthritis due to ScaphoLunate Advanced Collapse. LEVEL OF EVIDENCE: III.

Effect of print orientation on the dimensional accuracy and cost-effectiveness of rapid-prototyped dental models using a PolyJet photopolymerization printer: An in vitro study.

OBJECTIVES: The purpose of this study was to evaluate the accuracy and cost-effectiveness of the dental models 3D printed in vertical and horizontal orientation as compared to the conventional plaster and digital models. METHODS: This study involved scanning 50 plaster models using Maestro 3D Desktop Scanner (AGE Solutions, Pisa, Italy). The STL file obtained from the scanner was processed and three-dimensionally (3D) printed in the horizontal and vertical orientation using a PolyJet 3D printer (Objet 30 prime, Stratasys Ltd., Eden Prairie, Minnesota, United States). The accuracy of the rapid-prototyped (3D printed) models was measured from the pre-determined landmarks and was compared among the groups. In addition, determining the cost-effectiveness of the 3D printed models in different orientations was based on the amount of material (resin) utilized during the 3D printing process. ANOVA was used to determine the accuracy of the models. RESULTS: There were statistically insignificant differences (P>0.05) among rapid-prototyped models (≤0.06mm) compared to plaster models and digital models for the linear measurements made in all three planes of space. The dental models printed in the horizontal orientation were found to be more cost-effective than those printed in a vertical orientation in terms of the amount of material (resin) utilized and printing time during the 3D printing process. CONCLUSIONS: The accuracy of rapid-prototyped models 3D printed in the horizontal and vertical orientations was comparable to the plaster models and digital models for clinical applications. Horizontally printed models were more cost-effective than vertically printed models.

Development of a simple estimation method of serum caffeine concentration using a point-of-care test kit for urinary caffeine.

PURPOSE: Serum caffeine concentration is an indicator of caffeine intoxication; however, it is difficult to measure it in most emergency departments. We developed a simple estimation method using a point-of-care test kit for urinary caffeine. METHODS: Caffeine-spiked human serum (100, 50, 25, and 10 µg/mL) was diluted 10-, 20-, 50-, and 100-fold with phosphate-buffered saline and applied to the kit. After 5 min incubation, the kit was scanned by a flatbed scanner and the membrane image was processed with ImageJ. RESULTS: When the 20-fold diluted serum was applied, serum samples with initial caffeine concentration ≤ 25 and ≥ 50 µg/mL were caffeine-negative and -positive, respectively. When the 100-fold diluted serum was applied, none of the caffeine-spiked serum samples gave positive results. Therefore, we proposed the following test procedure: (i) 20-fold diluted serum was initially tested and (ii) 100-fold diluted serum was additionally tested when the initial result was caffeine positive. Using this procedure, caffeine concentration is expected to be classified into three levels: ≤ 25, > 25- ≤ 100, and > 100 µg/mL, which almost correspond to no or mild, severe, and potentially fatal intoxication, respectively. The test procedure was validated using postmortem heart blood from two cases of fatal caffeine intoxication (caffeine concentration: 276 and 175 µg/mL) and two cases of other intoxication. CONCLUSIONS: Our developed method using point-of-care urinary caffeine test kits enabled simple estimation of serum caffeine concentration.

Influence of scanning pattern on accuracy, time, and number of photograms of complete-arch implant scans: A clinical study.

OBJECTIVES: To measure the influence of scanning pattern on the accuracy, time, and number of photograms of complete-arch intraoral implant scans. METHODS: A maxillary edentulous patient with 7 implants was selected. The reference implant cast was obtained using conventional methods (7Series Scanner). Four groups were created based on the scanning pattern used to acquire the complete-arch implant scans by using an intraoral scanner (IOS) (Trios4): manufacturer's recommended (Occlusal-Buccal-Lingual (OBL)), zig-zag (Zig-zag), circumferential (Circumf), and novel pattern that included locking an initial occlusal scan (O-Lock group) (n = 15). Scanning time and number of photograms were recorded. The linear and angular measurements were used to assess scanning accuracy. One-way ANOVA and Tukey tests were used to analyze trueness, scanning time, and number of photograms. The Levene test was selected to assess precision (α=0.05). RESULTS: Statistically significant differences in trueness were detected among OBL, Zig-zag, Circumf, and O-Lock regarding linear discrepancy (P<0.01), angular discrepancy (P<0.01), scanning time (P<0.01), and number of photograms (P<0.01). The O-Lock (63 ± 20 µm) showed the best linear trueness with statistically significant differences (P < 0.01) with Circumferential (86 ± 16 µm) and OBL (87 ± 19 µm) groups. The O-Lock (93.5 ± 13.4 s, 1080 ± 104 photograms) and Circumf groups (102.9 ± 15.1 s, 1112 ± 179 photograms) obtained lower scanning times (P < 0.01) and number of photograms (P < 0.01) than OBL (130.3 ± 19.4 s, 1293 ± 161 photograms) and Zig-zag (125.7 ± 22.1 s, 1316 ± 160 photograms) groups. CONCLUSIONS: The scanning patterns tested influenced scanning accuracy, time, and number of photograms of the complete-arch scans obtained by using the IOS tested. The zig-zag and O-Lock scanning patterns are recommended to obtain complete-arch implant scans when using the selected IOS.

Predictors of flatfoot in 11-12-year olds: a longitudinal cohort study.

BACKGROUND: The structures around the navicular bones, which constitute the medial longitudinal arch, develop by 10 years of age. While navicular bone height is often emphasized in the assessment of flatfoot, three-dimensional (3D) evaluations, including those of structural parameters during inversion, have rarely been investigated. If the development of flatfoot during the growth process could be predicted, appropriate interventions could be implemented. Therefore, in this longitudinal cohort study, we developed a system, utilizing smartphones, to measure the 3D structure of the foot, performed a longitudinal analysis of changes in midfoot structures in 124 children aged 9-12 years, and identified factors influencing the height of the navicular bone. The foot skeletal structure was measured using a 3D system. RESULTS: Over 2 years, foot length and instep height increased during development, while navicular height decreased. The 25th percentile of the instep height ratio and navicular height ratio at ages 9-10 years did not exceed those at ages 11-12 years, with percentages of 17.9% and 71.6%, respectively, for boys, and 15.8% and 49.1%, respectively, for girls. As the quartiles of the second toe-heel-navicular angle (SHN angle) increased at ages 9-10 years, the axis of the bone distance (ABD) and SHN angles at ages 11-12 years also increased, resulting in a decrease in the navicular height ratio. A significant inverse correlation was found between changes in SHN angle and navicular height ratio. These findings indicate that the navicular bone rotation of the midfoot is a predictor of the descent of the navicular bone. CONCLUSIONS: This study revealed that some children exhibit decreases in navicular bone height with growth. As a distinct feature, the inversion of the navicular bone promotes flattening of the midfoot. Thus, this study provides insights into changes in midfoot development in children and provides an effective evaluation index.

Comparison of accuracy and speed between plaster casting, high-cost and low-cost 3D scanners to capture foot, ankle and lower leg morphology of children requiring ankle-foot orthoses.

BACKGROUND: Traditional plaster-cast fabrication of an ankle-foot orthosis (AFO), although robust, is time-consuming and cumbersome. 3D scanning is quickly gaining attention as an alternative to plaster casting the foot and ankle region for AFO fabrication. The aim of this study was to assess the accuracy and speed of two high-performing 3D scanners compared with plaster casting in pediatric patients requiring an AFO. METHODS: Ten participants (mean age 10.0 ± 3.9 years) prescribed AFOs for a movement disorder were 3D scanned with the high-cost Artec Eva (Eva) and low-cost Structure Sensor II (SSII) using one-person (1p) and two-person (2p) protocols. Accuracy and speed for both 3D scanners were compared with corresponding plaster cast measures (≤5% acceptable difference). Bland and Altman plots were generated to show mean bias and limits of agreement. RESULTS: Overall, Eva and SSII were accurate for foot, ankle, and lower leg key clinical landmarks (Eva-1p: 4.4 ± 7.3%; Eva-2p: 3.2 ± 7.5%; SSII-1p: 0.6 ± 7.4%; SSII-2p: 0.7 ± 8.2%). Bland and Altman plots for the SSII demonstrated lower biases for 1p (bias 0.5 mm, LoA: -12.4-13.5 mm) and 2p (0.4 mm, LoA: -11.4-12.2 mm) protocols compared with Eva for 1p (bias 2.3 mm, LoA: -8.0-12.7 mm) and 2p (1.8 mm, LoA: -10.7-14.3 mm) protocols. The SSII 2p protocol was the fastest 3D scanning method (26.4 ± 11.1 s). CONCLUSIONS: The high-cost Eva and low-cost SSII 3D scanners using the 1p and 2p protocols produced comparable accuracy and faster capture of key clinical landmarks compared with plaster cast measures for the fabrication of AFOs in pediatric patients.

Hybrid-resolution facial and dental scanning: a cost-effective approach to utilizing 3D facial data in anterior dental implant restoration.

As digital technology becomes more prevalent in the practice of dental medicine, methods to fully replace 2-dimensional photography and analog devices such as the facebow are still in their infancy. As more practices adopt 3-dimensional (3D) intraoral scanners, effective digital communication of the relationships between the teeth and the face becomes essential. With the high cost of intraoral scanners, the additional expense of a face scanner is not a feasible investment for many practices. This article explores a technique for meshing (lower resolution) facial data obtained from a smartphone-based scanner with high-resolution intraoral scan data. In this approach, the data from a free 3D scanning application on a smartphone and a traditional intraoral scanner are meshed so that high-resolution data are available for intraoral features and lower resolution data are used to capture the gross contours of the face. In this way, a hybrid-resolution composite scan that incorporates all of the data needed to simulate the face and accurately reproduce the teeth is generated without the cost of additional scanning equipment. This article defines a new term, the facial registration scan, for use alongside the familiar digital bite registration obtained with an intraoral scanner. To illustrate the clinical use of the hybrid-resolution scan concept, this article presents a case in which this method was used for the restoration of maxillary anterior implants.

Comparative Analysis of TLS and UAV Sensors for Estimation of Grapevine Geometric Parameters.

Understanding geometric and biophysical characteristics is essential for determining grapevine vigor and improving input management and automation in viticulture. This study compares point cloud data obtained from a Terrestrial Laser Scanner (TLS) and various UAV sensors including multispectral, panchromatic, Thermal Infrared (TIR), RGB, and LiDAR data, to estimate geometric parameters of grapevines. Descriptive statistics, linear correlations, significance using the F-test of overall significance, and box plots were used for analysis. The results indicate that 3D point clouds from these sensors can accurately estimate maximum grapevine height, projected area, and volume, though with varying degrees of accuracy. The TLS data showed the highest correlation with grapevine height (r = 0.95, p < 0.001; R2 = 0.90; RMSE = 0.027 m), while point cloud data from panchromatic, RGB, and multispectral sensors also performed well, closely matching TLS and measured values (r > 0.83, p < 0.001; R2 > 0.70; RMSE < 0.084 m). In contrast, TIR point cloud data performed poorly in estimating grapevine height (r = 0.76, p < 0.001; R2 = 0.58; RMSE = 0.147 m) and projected area (r = 0.82, p < 0.001; R2 = 0.66; RMSE = 0.165 m). The greater variability observed in projected area and volume from UAV sensors is related to the low point density associated with spatial resolution. These findings are valuable for both researchers and winegrowers, as they support the optimization of TLS and UAV sensors for precision viticulture, providing a basis for further research and helping farmers select appropriate technologies for crop monitoring.