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This article is the sixth in the Movement is Life series and focuses on insurance coverage and medication management in the perioperative period, 2 tangentially related variables that affect patient outcomes. Our aim is to use current practices and literature to develop recommendations for nurse navigators' execution of preoperative optimization protocols related to payer status and medication management. Discussions with nurse navigators and a literature search were used to gather information and develop recommendations specific to optimizing payer status and medication management. Nurse navigators connected patients to resources and provided education regarding financial concerns and medications, and findings from the literature discussed insurance status among TJA patients. Nurse navigators can contribute to payer status and medication management optimization by providing patient education and resource referrals. In addition, we recommend conducting repeated medication reconciliation and developing awareness of financial resources and perioperative medication management guidelines. [ABSTRACT FROM AUTHOR]

Mental health and housing status have the potential to impact total joint arthroplasty (TJA) outcomes and are common TJA eligibility criteria that prevent patients from receiving surgery. Our aim was to formulate recommendations for how nurse navigators can assist patients with managing mental health and housing concerns. Through discussions with nurse navigators and a literature search across two databases, we gathered information regarding the optimization of mental health and housing status among TJA patients. We observed a lack of standardized protocols for addressing these concerns and literature supporting an increased focus on mental health and housing status, indicating the potential for greater nurse navigator involvement in developing and implementing protocols. We recommend nurse navigators use screening tools to identify mental health and housing concerns and offer the suggested resources to support patients in an effort to improve postoperative outcomes and decrease surgical risks. [ABSTRACT FROM AUTHOR]

Background: Soft tissue thickness (STT) influences esthetics, peri-implant, and periodontal health. Non-invasive methods of STT evaluation include cone-beam computed tomography (CBCT) with Digital Imaging and Communications in Medicine (DICOM) files and registration of DICOM files with an intraoral scan or Standard Tessellation Language (STL) files. This study compares three methodologies: bone sounding, DICOM data alone, and DICOM and STL registration to absolute histomorphologic values.Methods: Five human maxillas, including teeth numbers 6 to 11, provided 90 sites for analysis. For standardization, reference grooves were placed at the cervical margin and the long axis of each tooth. Direct measurements with a no. 25 K-file were completed at the facial soft tissues at 3.00, 5.00, and 7.00 mm from the apical marginal reference. Indirect measures were performed with implant planning software. Histological measurements were rendered with imaging software. One-way analysis of variance (ANOVA) was used to compare the three techniques for the differences from histologic measurements (α = 0.05).Results: Seventy-two sites were included for final analysis. The overall mean histological STT (mSTT) was 0.73 ± 0.31 mm. Bone sounding overestimated mSTT, 0.22 ± 0.20 mm (P < 0.001); whereas, DICOM alone underestimated mSTT, -0.23 ± 0.19 mm (P < 0.001). DICOM and STL registration had non-statistically significant differences, -0.04 ± 0.21 mm (P = 0.429). Intraclass correlation coefficient (ICC) of DICOM and STL registration achieved the highest agreement with histology (ICC: 0.74).Conclusions: DICOM and STL file registration had the highest agreement with histological STT supporting the use of DICOM and STL registration for the evaluation of STT. [ABSTRACT FROM AUTHOR]

This technical report describes a novel workflow for complete denture fabrication designed to abbreviate the necessary steps for dental prostheses delivery by using a 3-appointment protocol in which preliminary impressions are made in the first session together with the registration of maxillary lip support, occlusal plane, and reference lines for tooth arrangement. A trial denture is fabricated with conventional or computer-aided design and computer-aided manufacturing procedures and is evaluated in the second appointment for esthetics, the definitive impression, and the maxillomandibular relationship record to provide precise references for definitive denture fabrication. [ABSTRACT FROM AUTHOR]

Studies suggest that posterior hip precautions are unnecessary after total hip arthroplasty; however, many surgeons and patients choose to follow these precautions to some extent. In this study, we hypothesized that 20° of hip abduction would be sufficient to prevent impingement and dislocation in motions requiring hip flexion when using larger prosthetic heads (≥36 mm) when the acetabular implant is placed within a reasonable orientation (anteversion:15-25° and inclination: 40-60°). Using a robotic hip platform, we investigated the effect of hip abduction on prosthetic and bony impingement in 43 patients. For the flexed seated position, anterior pelvic tilt angles of 10 and 20° were chosen, while anterior pelvic tilt angles of 70 and 90° were chosen for the bending forward position. An additional 10° of hip external rotation and 10 or 20° of hip internal rotation were also added to the simulation. One hip received a 32-mm head; otherwise, 36-, 40-mm, or dual-mobility heads were used. The study power was 0.99, and the effect size was 0.644. In 65% of the cases, bone-bone impingement between the calcar and anterior-inferior iliac spine was the main type of impingement. The absolute risk of impingement decreased between 0 and 16.3% in both tested positions with the addition of 20° hip abduction. With modern primary total hip arthroplasty stems (low neck diameter) and an overall acceptable cup anteversion angle, small degrees of hip abduction may be the only posterior hip precaution strategy required to lower the risk of dislocation among patients. Future studies can potentially investigate the concept of personalized hip precautions based on preoperative computer simulations, utilized implants, hip-spine relations, and final implant orientation. [ABSTRACT FROM AUTHOR]

Three-dimensional radiographic assessment of buccal bone thickness and its integrity from cone beam computed tomography (CBCT) plays an essential role in immediate implant placement. However, the accuracy of CBCT measurements for the assessment of buccal bone thickness adjacent to maxillary anterior teeth is not well understood. The purpose of this observational study was to evaluate the accuracy of measuring the buccal bone thickness of maxillary anterior teeth from CBCT compared with direct measurement from histologic sections. A secondary objective was to analyze whether a minimal level of buccal bone thickness of maxillary anterior teeth can be detected from the CBCT scan. Five embalmed human cadavers with a complete anterior dentition were included in this study, providing 30 teeth for evaluation. After preparing reference notches at the gingival margin of each tooth, the anterior segments were scanned. The buccal bone thickness at 3, 5, and 7 mm from the notches was measured on the cross-sections obtained from the CBCT and histomorphometric images for a total of 90 sites. The CBCT measurements were compared with the histomorphometric measurements, and their agreement was assessed by using the Bland-Altman plots and intraclass correlation coefficients. The sensitivity and specificity of buccal bone detection were calculated from the CBCT scan. Histologic examination showed absence of the buccal bone in 29 sites (32%). The mean ±standard deviation thickness of the buccal bone was 0.52 ±0.05 mm (range: 0 to 1.97 mm) from the CBCT analysis and 0.40 ±0.05 mm (range: 0 to 1.67 mm) from histology. Measurements obtained from the CBCT sections significantly overestimated the buccal bone thickness when compared with the histologic evaluation (P =.001). The intraclass correlation coefficient of buccal bone thickness between the CBCT and histology was ≤0.53, an agreement considered as poor. The sensitivity of the CBCT as a diagnostic tool to detect the presence or absence of the buccal bone was 75.4%, and the specificity was 65.5%. The buccal bone thickness of maxillary anterior teeth was less than 2 mm at all sites as measured with both CBCT and histology evaluations. CBCT measurements had relatively low accuracy and reliability for the measurement of buccal bone thickness. These findings should be considered when using CBCT as a measuring tool for thin bone structures. [ABSTRACT FROM AUTHOR]

Copyright of Informatica (03505596) is the property of Slovene Society Informatika and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Additively manufactured dental casts are gaining popularity as the digital workflow is adopted in dentistry. However, studies on their dimensional accuracy and stability under different storage conditions in the dental laboratory are lacking. The purpose of this in vitro study was to compare the effects of different additive manufacturing processes and storage conditions on the dimensional accuracy and stability of 3D-printed dental casts. A completely dentate maxillary typodont model was digitized 10 times with a dental laboratory laser scanner, and the standard tessellation language (STL) files were used to manufacture 3D-printed diagnostic casts with the digital light projection (DLP) 3D printer (Asiga MAX) and material jetting (MJ) 3D printer (ProJet 3510 DPPro). Twenty DLP-printed and 20 MJ-printed diagnostic casts were digitized within 24 hours of production. Subsequently, all 3D-printed diagnostic casts were stored for 3 months, either in closed laboratory boxes or in dental laboratory open-face plastic containers with direct exposure to full-spectrum balanced light. After 3-month storage, all 40 3D-printed casts were digitized again. All scanned files were compared with the corresponding STL files in a surface-matching software program. The dimensional accuracy was measured and compared by the root mean square (RMS, in μm). Repeated measures analysis of variance (ANOVA) was used to compare RMS values among the variables, and the Tukey honestly significant difference (HSD) test was used for post hoc multiple comparisons (α=.05). The casts produced from the DLP 3D printer had a significantly higher mean ±standard deviation RMS of 153.7 ±25.4 μm than those produced with the MJ 3D printer with RMS of 134.1 ±16.0 μm (P <.001). The storage condition (box storage versus light exposure) did not affect the accuracy of the DLP-printed casts (P =.615) or the MJ-printed casts (P =.999). When comparing all 3D-printed casts after 3-month storage, group DLP-3M-Lit had the highest mean ±standard deviation RMS of 163.0 ±26.5 μm, and group MJ-3M-Box had the lowest RMS of 132.8 ±16.9 μm. The DLP-printed casts stored under light exposure were significantly less accurate than the MJ-printed casts stored in the box (P =.048). DLP-printed casts stored under light exposure showed significant surface color change under visual inspection. The MJ 3D printer produced more accurate 3D-printed dental casts than the DLP 3D printer. After 3-month storage, the DLP-printed casts stored under light exposure were the least accurate, and the MJ-printed casts stored without light exposure were the most accurate. The surface color change of DLP-printed casts stored under light exposure after 3-month storage was evident. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although desktop stereolithography (SLA) 3D printers and photopolymerizing resin have been used increasingly in dentistry to manufacture surgical templates, studies investigating their clinical application are lacking. The purpose of this in vitro study was to evaluate the effects of build angle on the accuracy, printing time, and material consumption of additively manufactured surgical templates made with a desktop SLA 3D printer and photopolymerizing resin material. Fifty surgical templates were fabricated from 1 master digital design file using a desktop SLA 3D printer and photopolymerizing resin material at 5 different build angles (0, 30, 45, 60, and 90 degrees) (n=10). All surgical templates were digitized and superimposed with the master design file using best-fit alignment in the surface matching software program. Dimensional differences between the sample files and the original master design files were compared, and the mean deviations were measured in the root mean square (measured in mm, representing accuracy). The printing time and resin consumption for each specimen were recorded based on the information in the 3D printing preparation software program. ANOVA and the Fisher least significant difference (LSD) test were used to estimate the effects of build angles on the root mean square, printing time, and resin consumption (α=.05 for all tests). The groups 0 degree (0.048 ±0.007 mm) and 45 degrees (0.053 ±0.012 mm) had statistically significant lower root mean square values when compared with those of groups 30 degrees (0.067 ±0.009 mm), 60 degrees (0.079 ±0.016 mm), and 90 degrees (0.097 ±0.017 mm) (P <.001 for all comparisons, except P =.003 for groups 30 degrees versus 45 degrees). The group 90 degrees had statistically significant higher root mean square values than all other groups (P <.001 for all comparisons, except P =.010 when compared with the group 60 degrees). For the printing time, the group 0 degree required significantly less printing time than all other groups (hour:minute, 1:26 ±0:03, P <.001 for all comparisons). The group 90 degrees required significantly more printing time than all other groups (2:52 ±0:06, P <.001 for all comparisons). For resin consumption, the groups 0 degree (11.58 ±0.21 mL), 30 degrees (11.32 ±0.16 mL), and 45 degrees (11.23 ±0.16 mL) consumed similar amounts of resin. However, there was statistical significance between groups 0 degree and 45 degrees (P =.016). The group 90 degrees consumed the significantly least amount of resin (9.86 ±0.40 mL, P <.001 for all comparisons). With a desktop SLA 3D printer, the 0-degree and 45-degree build angles produced the most accurate surgical template, and the 90-degree build angle produced the least accurate surgical template. The 0-degree build angle required the shortest printing time but consumed the most resin in the printing process. The 90-degree build angle required the longest printing time but consumed the least amount of resin in the printing process. [ABSTRACT FROM AUTHOR]

Additive manufacturing or 3D printing is gaining popularity in dentistry, including for interim fixed dental prostheses (IFDPs). However, evidence regarding the color stability of 3D-printed IFDPs is lacking. The purpose of this in vitro study was to investigate whether different surface treatments could affect the color stability of milled and 3D-printed IFDPs after simulated physiological aging. Forty milled IFDPs were fabricated with a 5-axis dental mill (DWX-51D; Roland DGA Corp) from polymethyl methacrylate disks (Temp Esthetic 98, A3.5, 98.5×16 mm; Harvest Dental Products, LLC). Forty 3D-printed IFDPs were fabricated with an in-office digital light processing 3D printer (MAX; Asiga) and light-polymerizing resin (NextDent Crown & Bridge A3.5; NextDent B.V). All milled and 3D-printed IFDPs were allocated into 4 different groups (n=10), according to different surface treatments: Control, Polish, Optiglaze, and Skinglaze. In the Control group, no surface treatment was applied to the IFDPs. For the Polish group, IFDPs were finished and polished with aluminum oxide finishers/polishers (Enhance PoGo Complete Kit; Dentsply Sirona). For the Optiglaze and Skinglaze groups, specimens were first finished and polished and prepared with additional light-polymerizing protective coatings (Optiglaze; GC America Inc, or New Outline Skin Glaze; anaxdent North America). Shade measurements were recorded with a digital spectrophotometer (Vita Easyshade V; VITA North America) before and after the thermocycling for the color stability comparisons. The effects of interim prosthesis type and surface treatments on ΔE∗, ΔL∗, Δa∗, and Δb∗ were examined using 2-way analysis of variance (ANOVA), and ΔE∗ was considered as the primary outcome variable. Post hoc pairwise comparisons were performed by using the Tukey honestly significant difference (HSD) method (α=.05 for all tests). Milled IFDPs had significantly smaller ΔE∗ than 3D-printed prostheses for the Control group only (P <.001). Within the milled IFDPs, Optiglaze group (mean ±standard deviation, 1.01 ±0.38) had significantly lower ΔE∗ than all the other surface treatments groups (Control group: 2.38 ±0.44, P <.001; Polish group: 1.83 ±0.51, P =.025; and Skinglaze group: 1.85 ±0.78, P =.021). Within the 3D-printed IFDPs, the Control group (3.83 ±0.71) had significantly larger ΔE∗ than all other surface treatments (Polish group: 2.66 ±0.89, P =.018; Skinglaze group: 1.40 ±0.73, P <.001; and Optiglaze group: 1.37 ±0.67, P <.001). The Polish group had significantly higher ΔE∗ than Skinglaze group (P =.009) and Optiglaze group (P =.007), while Skinglaze and Optiglaze groups were not significantly different from each other (P =1.000). For the milled IFDPs, only the nano-filled, light-polymerizing protective coating significantly lowered color changes after thermocycling simulating 6 months of intraoral physiological aging. For the 3D-printed IFDPs, surface polishing and both light-polymerizing protective coating agents all significantly reduced color changes of the prostheses after thermocycling. The protective effect of light-polymerizing coating agents was more substantial. [ABSTRACT FROM AUTHOR]

The use of an integrated digital planning and manufacturing modular service and a time-tested dental implant system to treat a completely edentulous patient, as shown in this case report, offers numerous clinical benefits. Computer-guided surgery and digital dentistry have gained in popularity and demonstrated great clinical success; however, clinicians and dental laboratory technicians can further maximize the benefit gained from these technologies through additional training and resource investment. By using the streamlining solution (Smile in a Box®, Straumann) described in a clinical step-by-step manner in this case report, dental professionals can provide effective digital solutions for improved patient treatment acceptance, experience, and satisfaction. [ABSTRACT FROM AUTHOR]

The use of an integrated digital planning and manufacturing modular service and a timetested dental implant system to treat a completely edentulous patient, as shown in this case report, offers numerous clinical benefits. Computer-guided surgery and digital dentistry have gained in popularity and demonstrated great clinical success; however, dinicians and dental laboratory technicians can further maximize the benefit gained from these technologies through additional training and resource investment. By using the streamlining solution (Smile in a Box®, Straumann) described in a clinical step-by-step manner in this case report, dental professionals can provide effective digital solutions for improved patient treatment acceptance, experience, and satisfaction. [ABSTRACT FROM AUTHOR]

The novel Coronavirus Disease 2019 (COVID-19) is a global pandemic, and many countries and regions are still currently in the midst of the outbreak. This pandemic has caused prosthodontics units to suspend their clinical and educational operations in academia. The purpose of this article was to review the experiences from the Department of Prosthodontics, Wuhan University School and Hospital of Stomatology (DP-WHUSHS), during the COVID-19 outbreak and the protocols DP-WHUSHS used to resume clinical activities after the outbreak. The descriptive approach was used in this article to provide a chronological narrative of the experiences and protocols from the DP-WHUSHS during the COVID-19 outbreak and after the outbreak. During the COVID-19 outbreak period, clinical care was provided for patients with dental emergencies by using enhanced grade 2 or grade 3 personal protective equipment (PPE). Teledentistry was used to provide care for patients with nonemergency needs. Online webinars and lectures were conducted for the predoctoral students, residents, and dentists to minimize the interruption in their education and engage the dental community amid the pandemic. Various factors were considered before clinical activities resumed after the outbreak subsided. Additional resources were allocated for facility preparation and management and employee training. New infection control and clinical operation protocols were developed to minimize the health-care–associated infection of airborne transmission diseases. The psychological health and mental wellness of the employees were emphasized. Distance or online education is still under rapid development to provide students and dentists opportunities to advance their knowledge amid the pandemic. Within the limitation of this descriptive review, the following conclusions were drawn. Patient welfare and emergency needs should be considered amid the pandemic. Enhanced grade 2 or grade 3 PPE should be used during the outbreak. Multifactorial considerations for work resumption after the outbreak included facility preparation and management, training for employees, and clinical operation management. In-person psychological consultation and online mental wellness programs were available to employees to improve their mental wellness. Distance or online education was under rapid development to minimize the interruption in education for the students and to engage the dental community amid a pandemic. [ABSTRACT FROM AUTHOR]

• The Sn 4 P 3 /GO-PEG200 nanohybrid was readily synthesized through an ambient temperature solid state reaction followed by phosphorization. • Sn 4 P 3 nanoparticles (50–100 nm) were inlaid within graphene oxide matrix in the Sn 4 P 3 /GO-PEG200 nanohybrid. • The Sn 4 P 3 /GO-PEG200 nanohybrid exhibits an outstanding sodium-storage behavior as anode material for SIBs. Due to nature abundant and low-cost of sodium reserves with broad distribution in the earth's crust, sodium-ion batteries (SIBs) have attracted widespread attention for their great potential application in low-speed electric vehicles and large-scale energy storage system. However, their practical application is still hampered by the lack of decent anode materials. In this work, we develop an effective strategy to fabricate a nanohybrid of Sn 4 P 3 and graphene oxide and demonstrate its outstanding sodium-storage behavior as an anode material for SIBs. By directly grinding tin(IV) chloride pentahydrate, sodium hydroxide, graphene oxide (GO) and surfactant PEG-200 at ambient temperature, an effective solid state reaction occurred to give rise to a precursor (named as SnO 2 /GO-PEG200), i.e. a nanocomposite of SnO 2 encapsulated within GO matrix. After subsequent phosphorization at 280 °C using sodium hypophosphite monohydrate as phosphorous source, a nanohybrid of Sn 4 P 3 and graphene oxide (designated as Sn 4 P 3 /GO-PEG200) was acquired. The coexistence of Sn 4 P 3 nanoparticles and GO nanosheets endows the nanohybrid with improved electronic conductivity, highly structural integrity and superior electrochemical performance. When employed as anode material for SIBs, the nanohybrid anode demonstrates a good cycling stability (419 mA h g−1 after 100 cycles at 0.1 A g−1), with a remarkable rate capabilities (325 mA h g−1 at a current density of 1 A g−1 and 187 mA h g−1 at a current density of 5 A g−1, respectively). Sn 4 P 3 /GO-PEG200 nanohybrid was fabricated by an ambient temperature solid state reaction followed by phosphorization at a relatively low temperature. When employed as anode materials for SIBs, the as-prepared nanohybrid exhibited outstanding sodium-storage behavior in terms of excellent cycling stability and impressive rate capabilities. [Display omitted] [ABSTRACT FROM AUTHOR]

This technique describes a workflow to align the maxillary and mandibular edentulous intraoral scans in the computer-aided design and computer-aided manufacturing (CAD-CAM) software program for the fabrication of CAD-CAM implant-retained overdentures. Using the patient's existing and clinically satisfactory interim complete dentures as an aid for the interocclusal record, this technique provides a convenient option for aligning edentulous intraoral scans without the need for an additional clinical appointment, record base, or maxillomandibular tracing device. [ABSTRACT FROM AUTHOR]

This technical report describes a digital process to design and fabricate a verification device directly from an intraoral scan for nonsegmental implant-supported dental prostheses. By using an open source computer-aided design software program, this technique provides an economical option for dentists and dental laboratory technicians to fabricate a computer-aided design and computer-aided manufacturing (CAD-CAM) verification device. This technique is particularly beneficial for a long scanning span and large edentulous space with multiple scan bodies, and a verification device can be used to confirm the accuracy of a CAD-CAM implant definitive cast. [ABSTRACT FROM AUTHOR]

Currently available assessment tools for evaluating the esthetic outcome of implant restorations consist of objective indices created for dentists. The investigation of esthetic parameters according to the patient's perspective is lacking. The purpose of this observational study was to evaluate and compare the importance of different soft-tissue and restoration-related esthetic parameters for patients and clinicians. A photoediting software program (Photoshop CC; Adobe Corp) was used to produce 10 photographs with modified smiles from the original photograph by altering 1 parameter of the pink esthetic score and white esthetic score (PES/WES) at a time. A total of 120 participants were recruited in the study, including 40 laypeople, 40 prosthodontists, and 40 periodontists. A total of 440 visual analog scale (VAS) values were obtained for each group to record participants' subjective esthetic assessments of all photographs (10 modified and 1 original photograph). Repeated-measures ANOVA and post hoc mean comparison (t grouping) were used to identify whether the individual alteration on the PES and WES indices was significant for each group. For the laypeople, color (hue and value) appeared to be the most important parameter. After color, the order of importance was as follows: root convexity along with soft-tissue color and texture, level of facial mucosa, distal papilla, mesial papilla, translucency or characterization, surface texture, and tooth form. For the periodontists, color (hue and value) was also the most important parameter, but it was not separable from a cluster of other parameters: level of facial mucosa, root convexity along with soft-tissue color and texture, mesial papilla, and distal papilla. For the prosthodontists, color (hue and value) and level of facial mucosa were the most important parameters affecting esthetic assessment, followed by root convexity along with soft-tissue color and texture, mesial papilla, and distal papilla. All groups graded color (hue and value) as the most important parameter affecting the esthetic outcome and the original unaltered photograph as the most esthetically pleasing image. All participants (laypeople and dental specialists) appeared to be able to perceive the same 5 parameters including color (hue and value), level of facial mucosa, mesial papilla, distal papilla, and root convexity along with soft-tissue color and texture that are negatively affecting esthetic outcomes. Except for color (hue and value), restoration-related esthetic parameters had a lesser effect on the overall esthetic assessments for all groups. [ABSTRACT FROM AUTHOR]

Candida albicans has been implicated in denture stomatitis, and this effect is exacerbated by nicotine exposure. However, studies have also suggested that caffeine exposure inhibits the growth of C. albicans. The interaction effects of nicotine and caffeine are not yet clear on the growth of C. albicans. The purpose of this in vitro study was to determine the effect of caffeine on metabolic activity and biofilm formation of C. albicans growing on acrylic denture resin while simultaneously exposed to nicotine and, if an effect were to be identified, whether this effect would vary depending on the caffeine concentration. A total of 240 acrylic resin specimens were divided into 2 equal groups (120 each). Specimens in one group were processed to measure C. albicans metabolic activity, and those in the other group were processed to measure C. albicans biofilm attachment. Ten subgroups (n=12) were established within each group with different concentration combinations of nicotine and caffeine to test the interaction effect. The first subgroup was designed as a negative control, containing 0 mg/mL of nicotine and caffeine. The following subgroups all contained 8.00 mg/mL of nicotine, and the caffeine concentrations were prepared at the following 9 levels: 0, 0.25, 0.50, 1.00, 2.00, 4.00, 8.00, 16.00, and 32.00 mg/mL. Metabolic activity was measured by using a 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-carboxanilide (XTT) assay. Biofilm attachment was measured by using spiral plating and calculated in terms of the number of colony-forming units (CFUs)/mL. Descriptive statistics and a 2-way ANOVA were conducted to determine whether the concentrations of nicotine and caffeine used affected the biofilm attachment and metabolic activity of C. albicans (α=.05). The presence of 8 mg/mL of nicotine increased the metabolic activity and biofilm formation of C. albicans. When compared with the 0 mg/mL of caffeine and 8.00 mg/mL of nicotine group, caffeine from 1.00 to 4.00 mg/mL significantly increased C. albicans biofilm metabolic activity. Caffeine at 16.00 and 32.00 mg/mL significantly decreased C. albicans biofilm metabolic activity in the presence of 8 mg/mL of nicotine. Caffeine from 1.00 to 32.00 mg/mL significantly decreased the biofilm formation of C. albicans in the presence of 8 mg/mL of nicotine. The presence of 8 mg/mL of nicotine alone increased the metabolic activity and biofilm formation of C. albicans. In the presence of 8 mg/mL of nicotine with different caffeine concentrations, the results suggest that, overall, caffeine at higher concentrations (16 and 32 mg/mL) inhibited the metabolic activity and biofilm formation of C. albicans on acrylic denture resin most. [ABSTRACT FROM AUTHOR]

Intraoral scans and virtual interocclusal records (VIRs) are widely used for contemporary prosthodontic treatment of patients with partial edentulism. The accuracy of VIRs in various clinical conditions is unclear. The purpose of this in vitro study was to investigate whether the span and location of edentulous areas affect the accuracy of VIRs. Five sets of master stone casts were duplicated from a typodont model (Prosthetic Restoration Jaw Model; Nissin Dental) and then assigned into 5 study groups. Six pairs of interarch markers were placed on the master stone casts as reference points for measurements. The 5 study groups were group 1-Post: 1 posterior tooth missing; group 3-Post: 3 posterior teeth missing; group 6-Ant: 6 anterior teeth missing; group Bil-Post: bilateral posterior teeth missing; and group Dent: completely dentate arch. Master stone casts along with VIRs were scanned 10 times in each group by using an intraoral scanner (IOS) (Dental Wings Intraoral Scanner; Dental Wings Inc). Digital measurement of distances between the interarch markers was obtained on all digitally articulated casts and compared with the manual measurements (with electronic calipers with an accuracy of 0.02 mm). In addition, the differences (absolute values) between the digital and manual measurements were calculated at the edentulous locations for the groups 1-Post, 3-Post, 6-Ant, and Bil-Post and were compared with the corresponding interarch marker positions in the group Dent. Two-sample t tests were used for the statistical analysis (α=.05). The overall differences (mean ±standard deviation) between digital and manual measurements were group 1-Post: 0.10 ±0.19 mm, group 3-Post: 0.28 ±0.63 mm; group 6-Ant: 0.19 ±0.20 mm; group Bil-Post: 0.28 ±0.25 mm; and group Dent: 0.05 ±0.18 mm. Group Dent was the only group with no significant differences between digital and manual measurements at all 6 interarch marker positions and was used as the reference to analyze the measurements in the edentulous areas. No statistical difference was found (P =.237) at the group 1-Post's edentulous area when compared with the group Dent. In the group 3-Post, the edentulous areas showed statistically significant difference when compared with those of the group Dent (P =.002 and P =.003). In the group 6-Ant, the edentulous areas showed statistical differences when compared with those of the group Dent (P =.019 and P =.008). In the group Bil-Post, only 1 side of the edentulous areas showed statistical differences when compared with group Dent (P =.006 and P =.034). The span and location of edentulous areas impact the accuracy of VIRs. For a single missing posterior tooth, VIRs could achieve a high level of accuracy comparable with that of the dentate condition. Unilateral and bilateral extended edentulous spans with 3 or more missing posterior teeth and the extended edentulous span in the anterior region all affected the accuracy of VIRs. [ABSTRACT FROM AUTHOR]

The socket-shield technique can be challenging and time-consuming. This article presents a digital approach to fabricating a computer-aided design and computer-aided manufacturing (CAD-CAM) titanium preparation template for the socket-shield technique. Preoperative cone beam computed tomography (CBCT) was used to map the remaining root, and the desired shape of buccal fragment of the root was determined as the socket shield. A CAD-CAM titanium preparation template was fabricated to facilitate root sectioning and the preparation procedure for forming an adequate socket shield. [ABSTRACT FROM AUTHOR]

The Aschenbach effect, the increasing behavior of the angular velocity of a timelike circular orbit with its radius coordinate, is found to extensively exist in rapidly spinning black holes to a zero-angular-momentum observer. It also has potential observation in the high-frequency quasi-periodic oscillations of X-ray flux. However, observing such effect remains to be a challenge in static and spherically symmetric black hole backgrounds. In this paper, we mainly focus on such issue. Starting with the geodesics, we analytically study the underlying properties of the timelike circular orbits, and show the conditions under which the Aschenbach effect survives. It is shown that the presence of the static point orbits and stable photon spheres would be the indicator of the Aschenbach effect. We then apply it to three characteristic black holes exhibiting different features. The results state that this effect is absent for both the Schwarzschild and Reissner-Nordström black holes. While, for the dyonic black hole in quasi-topological electromagnetics, there indeed exists the Aschenbach effect. This provides a first example that such effect exists in a non-spinning black hole background. Moreover, it also uncovers an intriguing property for understanding the black holes in nonlinear electrodynamics. [ABSTRACT FROM AUTHOR]

In total hip arthroplasty (THA), femoral offset restoration results in optimal biomechanics and range of motion (ROM) without bone-bone impingement. We hypothesized that differences in implant design features significantly affect bone-bone impingement risk in primary THA. This retrospective computer simulation study included a cohort of 43 primary robotic arm–assisted THA. Considering sagittal pelvic tilt, we measured the maximum external rotation at 0° hip flexion and the maximum internal rotation at both 90° and 100° hip flexion before any bone-bone impingement occurred. To influence the offset, we included neutral or extended polyethylene liners, neutral or plus prosthetic heads, standard or high-offset stems, and stems with 132° or 127° neck angles. Extended polyethylene liner use resulted in decreased bone-bone impingement for both stems but also decreased prosthetic ROM in hip extension (mean −4.5 to 5°, range −10 to 0°) and hip flexion (mean −3 to 3.7°, range −10 to 0°) due to decreases in head diameter. Using a plus head or different stem offset/neck angle options resulted in either (1) no improvement in ROM (stem 1: 60%; stem 2: 28%) or (2) a paradoxical increase in bone-bone impingement (stem 1 with 127°: 19% and stem 2 with high offset option: 7%). Counterintuitively, a subset of patients experience a paradoxical increase in bone-bone impingement when transitioning from standard to high-offset or varus necks due to the pelvic and proximal femoral bone shape. For this group of patients, preoperative personalized 3-dimensional modeling may help guide implant choice for optimizing outcomes. [ABSTRACT FROM AUTHOR]

The accuracy of intraoral scans, particularly in edentulous areas, remains a concern despite the increasing use of digital technology, especially intraoral scanners. The purpose of this in vitro study was to assess the impact of the extent of an edentulous area on the accuracy (trueness and precision) of intraoral scans from 2 intraoral scanners. A KaVo dentoform with epoxy resin teeth was used to generate 9 groups with different numbers of teeth removed. A laboratory scanner served as the reference dataset, and 2 intraoral scanners (TRIOS 3 and Primescan AC) were evaluated. A single operator performed all scans following standardized protocols and calibration. Trueness and precision were assessed by using root mean square (RMS) values. Analysis of variance was used to compare trueness and precision values obtained from the 2 scanners and different partially edentulous conditions (α=.05). A significant difference was found in the trueness of intraoral scans of the 2 scanners and under different partially edentulous extensions. Primescan AC exhibited significantly lower trueness than TRIOS 3 (P <.001). For the individual edentulous conditions, Primescan had a significantly higher RMS mean than TRIOS 3 for G0, G3, G4, G6, G7, and G8 (P <.001) and a significantly lower RMS mean than TRIOS 3 for G1 and G4 (P <.001), while no significant difference in RMS mean was found between the 2 scanners for G2 (P =.999). For precision, no significant difference was found between the 2 scanners or different edentulous conditions [(F 8, 90)=1.82, P =.085]. The accuracy of intraoral scans was influenced by the length of edentulous areas and the scanner used. Primescan AC demonstrated lower trueness than TRIOS 3 for most partially edentulous conditions, while the scanners were similar in precision. These findings highlight the need for careful scanner selection in specific clinical situations, as scanning accuracy may vary depending on the scanner and edentulous condition. [ABSTRACT FROM AUTHOR]

This is the second part of a JPD Digital presentation focusing on commonly seen complications and solutions related to using digital technologies in treating edentulous patients during the surgical and prosthetic stages. The proper usage of the computer-aided design and computer-aided manufacturing surgical templates and immediate loading prosthesis during computer-guided surgery and accurate translation of digital planning into clinical execution are discussed. In addition, design concepts of implant-supported complete fixed dental prostheses are presented to minimize subsequent issues in their long-term clinical service. In concert with these topics, this presentation will allow clinicians to deepen their understanding of the advantages and limitations of utilizing digital technologies in implant dentistry. [ABSTRACT FROM AUTHOR]

The increased precision and design of surgical templates for static computer-aided implant surgery has led to concerns of excessive heat generation from the friction between the twist drills, metal sleeves in the surgical template, and guide handles during osteotomy preparation. In addition, the presence of a surgical template can prevent proper cooling of the twist drill as it enters the osteotomy site, leading to greater heat generation. This excessive heat may result in bone necrosis and failure of osseointegration to the implant surface. This article describes a straightforward technique of incorporating an existing design feature in many virtual implant planning software programs to add an irrigation channel to the implant surgical template for effective cooling during osteotomy preparation. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate dental students' clinical shade-matching outcomes (from subjective use of shade guide) with an objective electronic shade-matching tool (spectrophotometer); to assess patients', students', and supervising faculty members' satisfaction with the clinical shade-matching outcomes; and to assess clinicians' support for use of the spectrophotometer to improve esthetic outcomes. A total of 103 volunteer groups, each consisting of patient, dental student, and supervising faculty member at the University of Louisville, were recruited to participate in the study in 2015. Using the spectrophotometer, clinical shade-matching outcome (ΔEclinical) and laboratory shade-matching outcome (ΔElaboratory) were calculated. Two five-point survey items were used to assess the groups' satisfaction with the clinical shade-matching outcome and support for an objective electronic shade-matching tool in the student clinic. The results showed that both ΔEclinical (6.5±2.4) and ΔElaboratory (4.3±2.0) were outside the clinical acceptability threshold ΔE values of 2.7, when visual shade-matching method (subjective usage of shade guide) was used to fabricate definitive restorations. Characteristics of the patients, dental students, supervising faculty members, and restorations had minimal to no effect on the ΔEclinical The patients, dental students, and supervising faculty members generally had positive opinions about the clinical shade-matching outcome, despite the increased ΔEclinical observed. Overall, clinical shade-matching outcomes in this school need further improvement, but the patients' positive opinions may indicate the need to revisit the acceptability threshold ΔE value of 2.7 in the academic setting. [ABSTRACT FROM AUTHOR]

The treatment of complete or single arch edentulism remains a significant priority for dental clinicians. Patients often request immediate loading for complex complete arch treatments with shorter treatment times and fewer appointments, and digital technologies can be leveraged to provide more effective treatments. This part 1 presentation focuses on the discussion of commonly seen complications related to using digital technologies in treating edentulous patients during the data collection and surgical planning stages. Complications related to digital technologies can be prevented or corrected during these stages, preventing future complications in the clinical (surgical and prosthetic) stages. [ABSTRACT FROM AUTHOR]

This technical report describes a digital process for designing and fabricating a stackable definitive cast and die system to facilitate the fabrication of a new surveyed crown to retrofit to a removable partial denture (RPD). By using an open-source computer-aided design (CAD) software program, this technique provides an economical option for dental clinicians and laboratory technicians to use intraoral scans and design a stackable definitive cast and die system with minimal financial investment in the CAD software. In addition, this technique provides the advantage of a conventional indirect technique in that it can create a definitive cast with an RPD clasp assembly ready for the dental technician to properly contour the new surveyed crown, but without the need for the patient to be without the RPD during the process. [ABSTRACT FROM AUTHOR]

Additively manufactured surgical templates are commonly used for computer-guided implant placement. However, their accuracy, reproducibility, and dimensional stability have not been thoroughly investigated with the different 3D printers and materials used for their fabrication. The purpose of this in vitro study was to evaluate the accuracy, reproducibility, and dimensional stability of additively manufactured surgical templates fabricated by using different 3D printers. Thirty surgical templates were designed and additively manufactured from 3 different 3D printers as follows: group SLA (n=10) was fabricated by using a desktop stereolithography (SLA) 3D printer and photopolymerizing resin; group PolyJet (n=10) was fabricated by using a PolyJet 3D printer and photopolymerizing resins; and group DMP (n=10) was fabricated by using a direct metal printing (DMP) system and Co-Cr metal alloy. All surgical templates were scanned by using a laser scanner within 36 hours of production and digitalized again 1 month later. All scanned files were compared with the corresponding designed files in a surface matching software program. The mean deviation root mean square (RMS, measured in mm, representing accuracy), percentage of measurement data points within 1 standard deviation of mean RMS (in %, representing reproducibility), and dimensional changes were determined and compared. At the postproduction stage, group PolyJet was most accurate with the lowest RMS value of 0.10 ±0.02 mm and highest reproducibility with 93.07 ±1.54% of measurement data points within 1 standard deviation of mean RMS. After 1-month storage, group PolyJet (1month) remained the most accurate with the lowest RMS value of 0.14 ±0.03 mm and the highest reproducibility value of 92.46 ±1.50%. For dimensional stability, group SLA versus group SLA (1month) comparison showed a significant decrease in accuracy (RMS values of 0.20 ±0.08 mm versus 0.25 ±0.08 mm, P <.001) and reproducibility (88.16 ±3.66% versus 86.10 ±4.16%, P =.012). Group PolyJet versus group PolyJet (1month) comparison only showed significant changes in accuracy (RMS values of 0.10 ±0.02 mm versus 0.14 ±0.03 mm, P =.011). Group DMP versus group DMP (1month) comparison showed no significant changes in accuracy (RMS values of 0.19 ±0.03 mm versus 0.20 ±0.04 mm, P =.981) or reproducibility (89.77 ±1.61% versus 89.74 ±2.24%, P =1.000). Printed resin surgical templates produced by using the PolyJet 3D printer showed higher accuracy and reproducibility than those produced by using the desktop SLA 3D printer and printed Co-Cr surgical templates at both the postproduction stage and after 1-month storage. The level of accuracy and reproducibility in printed Co-Cr surgical templates was not affected by 1-month storage. [ABSTRACT FROM AUTHOR]

Chronic exposure to fluoride is a public health problem worldwide. We explored the relationship between fluoride exposure, orthopedic injuries and bone formation markers alkaline phosphatase ( ALP), bone Gla protein ( BGP) in participants with coal-burning fluorosis in Hehua Village (coal-burning fluorosis endemic area) in Zhijin County of Guizhou Province and Zhangguan Village (non-fluoride contaminated area) in Anshun City of Guizhou Province. Environmental samples were collected and fluoride contents were examined using a fluoride ion-selective electrode. Dental fluorosis and skeletal fluorosis of 295 participants from Hehua Village and 85 participants from Zhangguan Village were diagnosed with informed consent. Urinary samples and peripheral blood samples were collected from the participants to determine urinary fluoride ( UF), ALP activity, and BGP content. The results showed that fluoride contents in rice, pepper, corn, drinking water, clay, vegetable-grown soil, coal and indoor and outdoor air were significantly higher than those in the control area, but lower than the previously reported values. With the increases of UF concentration, the ALP activity and BGP content significantly increased, the severity of skeletal fluorosis was greater, but with no significant changes in dental fluorosis. There was positive correlation between the severity of skeletal fluorosis and ALP activity, BGP content. These results indica- ted that low fluoride exposure could cause orthopedic injuries. ALP and BGP could be used to evaluate the bone turnover in patients with skeletal fluorosis, which would be useful in the auxiliary diagnosis and therapeutic evaluation of skeletal fluorosis. [ABSTRACT FROM AUTHOR]

Digital advances have changed implant planning to improve outcomes in placement and restoration. Layering multiple image inputs, such as volumetric radiology, photography, and 3-dimensional (3D) surface scans, has allowed better assessment of patients with partial or complete edentulism, and this can aid in producing 3D visual predictions, implant guides, and prosthetics to execute the proposed plan. [ABSTRACT FROM AUTHOR]