Evaluating the impact of scan body angulation and geometric attachments on the accuracy of complete-arch digital implant impressions: A comparison of two intraoral scanners.

PURPOSE: To investigate the effects of scan body (SB) angulation and geometric attachments (GAs) on the deviations of complete-arch digital implant impressions obtained using intraoral scanners (IOSs), in relation to the gold-standard desktop scanner. MATERIAL AND METHODS: Two IOSs (iTero and Omnicam), two SB angulations (0 degrees and 30 degrees), and GAs for the SBs were investigated. SBs were attached to an edentulous maxillary cast with the following implant analogs: parallel 0-degree at positions #13, #23, and #26, and 30-degree posteriorly tilted at position #16. The cast was digitized using a reference desktop scanner, followed by ten consecutive digital scans using each IOS (five scans with GAs and five without GAs, n = 20). Meshes obtained from the IOS scans were superimposed on the master reference mesh. Linear distance and 3D surface deviations from the reference mesh were calculated. A three-way multivariate analysis of variance (MANOVA) was employed to assess the effects of angulation, IOS type, and GAs on the combined dependent variables (α = 0.05). RESULTS: No significant three-way interaction was observed between IOS type, SB angulation, and GAs for combined deviations from the reference scan (p = 0.56). Simple main effect analysis revealed that iTero exhibited significantly lower mean 3D surface and linear deviations than Omnicam (p < 0.05). Additionally, the use of GAs significantly reduced deviations (p < 0.001), with mean deviation reductions for both scanners ranging from 26-33 micrometers (µm) for 3D deviations and 15-21 µm for linear distance deviations. No differences were found between angled and parallel SBs regarding 3D surface and linear distance deviations (p ≥ 0.05). CONCLUSIONS: ITero demonstrated significantly smaller deviations, and the use of GAs led to significantly reduced distance and 3D surface deviations. SB angulations did not impact scan deviations.

Thickness-Dependent Light Transmittance and Temperature Rise in Dual-Cure Bioactive and Light-Cure Bulk-Fill Composite Resins.

This study aimed to assess the light transmittance (T) and temperature increase through different increments of dual-cure bioactive bulk-fill restorative material (ACTIVA), light-cure bulk-fill, and conventional composite resin materials. Cylindrical specimens with a diameter of 8 mm and heights of 1, 2, 3, and 4 mm of ACTIVA, Tetric-N-Ceram bulk-fill (TBF), Filtek One bulk-fill (FBF), and Filtek Z250 (FZ) (n = 6 per group, 96 in total) were light-cured with a visible blue low-intensity light-emitting diode (LED) (650-800 mW/cm2 irradiance). T, and the temperature increase, were measured using an optical power meter and a digital thermometer during curing. The T mean values ranged between 0.012 and 0.239 (76.02 to 98.81% light attenuation), while the temperature rise mean values ranged between 9.02 and 20.80 °C. The parameters, including material type (partial eta squared (ηp2) = 0.284, p < 0.0001), thickness (ηp2 = 0.284, p < 0.0001), and their interaction (ηp2 = 0.185, p = 0.047), significantly affected the T values, whereas only the material type (ηp2 = 0.352, p = 0.047) affected the temperature rise values. The T and temperature rise mean values were highest in ACTIVA increments of 1-mm increments, in particular, showing the highest T mean values, followed by similar increments of TBF. A significantly higher T was found in 1-mm increments compared to thicker increments for all materials (p < 0.0001), and a significant positive correlation existed between T and temperature rise values (r = 0.348, p = 0.001). These findings show that the bioactive material ACTIVA and TBF allow for better T than the other materials, with ACTIVA recording a higher temperature rise. However, the large light attenuation observed for all materials, irrespective of thickness, suggests that curing in more than one location with a low-intensity LED is necessary to optimize the curing process. Furthermore, incremental filling of bulk-fill materials using a low intensity LED could be beneficial.

Evaluation of separating media for autopolymerizing acrylic resin fabricated on 3D-printed acrylate-based resin dental casts.

STATEMENT OF PROBLEM: Limited data are available regarding the most suitable separating medium for fabricating dental acrylic resin prostheses or appliances on 3-dimensional (3D)-printed resin casts. PURPOSE: The purpose of this in vitro study was to investigate and evaluate different separating media in terms of the ease of removal and detail reproduction of an autopolymerizing acrylic resin fabricated on acrylate-based 3D-printed resin casts. MATERIAL AND METHODS: A cube-shaped cast was designed with a built-in truncated cone-shaped hole and a V-shaped groove at the base. Seventy-five casts were 3D-printed using acrylate-based resin and assigned to 5 groups according to the applied separating media: Siliform BEA (silicone-based), IMPRIMO 3D (alginate-based), 3D Modellisolierung (wax-based), TECHNOSIL (alginate-based), and none (control). After the application of the separating media, the truncated cone-shaped holes in the specimens were filled with autopolymerizing acrylic resin. The efficacy of the separating media was evaluated according to the ease of removal on a scale of 1 to 3 and accurate detail reproduction of the V-shaped groove on a scale of 1 to 3 under ×6 magnification. The nonparametric Kruskal-Wallis rank test was used to identify significant differences among the separating media (α=.05). RESULTS: Significant differences were found among the groups (P<.001). Siliform BEA and 3D Modellisolierung had the best mean rank in both the ease of removal and detail reproduction scores, which were significantly different from those of the alginate-based separating media (IMPRIMO 3D and TECHNOSIL) and the control group (P<.01). CONCLUSIONS: The dedicated silicone- and wax-based separating media for 3D-printed casts exhibited the most favorable performance in terms of ease of removal and detail reproduction.

Knowledge and Attitudes of Saudi Medical Students about Emergency Management of Traumatic Dental Injuries.

Several studies indicate that physicians lack emergency management knowledge concerning traumatic dental injuries (TDIs), emphasizing the fact that medical students are not taught about this topic. This study aimed to assess the basic knowledge and attitudes of medical students in Saudi Arabia about emergency TDI management. This cross-sectional study recruited a convenience sample of medical students in their clinical years through social networking sites and asked them to answer a pretested internationally accepted questionnaire that included demographic questions, two case scenarios about crown fractures and avulsion of permanent teeth, and self-assessment questions. The data were analyzed statistically using descriptive statistics and the chi-squared test (p < 0.05). A total of 761 medical students responded. Only 5.8% of the students reported receiving information about TDIs in their curriculum. Medical students, mainly those ready to graduate, were more knowledgeable of the emergency management of a crown fractured permanent tooth than an avulsed permanent tooth (p < 0.0001). However, more than half of the students were unable to differentiate between a primary versus permanent fractured tooth and would manage an avulsed primary or permanent tooth similarly. Regarding students' attitudes, less than one-quarter of the students (13.5%) were confident about diagnosing TDIs and/or providing emergency management when required (18.1%). Furthermore, only about one-tenth of the students (9.3%) were satisfied with their self-perceived knowledge, and most (71%) reported needing further education about the topic. Medical students in Saudi Arabia have insufficient knowledge about the emergency management of TDIs. Gaps in students' knowledge of emergency management of avulsion injury were identified in addition to their low confidence level to either diagnose or immediately treat TDIs if required. Students felt dissatisfied with their current knowledge level, this being most prominent among graduating students. There is a need to elaborate the undergraduate medical curriculum in Saudi Arabia to include emergency management of TDIs.

Levels and correlates of knowledge of teething among Saudi Arabian families.

Background: Parental knowledge of teething has been repeatedly investigated; however, little emphasis has been made on the associated sociodemographic factors with good knowledge of the parents and whether or not good knowledge is translated into adopting proper pain-relieving practices. The present study aims to firstly assess the knowledge level and practices of Saudi parents regarding teething and then explore associated sociodemographic variables with good knowledge of teething to determine the relation between parents' knowledge of teething and their adoption of pain-relieving practices. Methods: This cross-sectional study recruited parents from the social networking sites Facebook, Twitter, Instagram, and WhatsApp, and they were asked to answer a pretested three-part internationally accepted questionnaire. Data were examined using descriptive statistics, chi-square analysis, multivariate logistic regression analysis, and Spearman rank-order correlation coefficient analysis. Results: One thousand four hundred ninety-nine parents responded and returned completed questionnaires. Of those, only 11.2% had good knowledge of teething. The majority of parents did not have basic knowledge of the teething period as well as believed that teething was associated with a runny nose (87.5%), diarrhea (77.9%), and sleep disturbance (72%). The results of multivariate logistic regression analysis indicated that parents with no primary school education (Odds Ratio: 0.29), or those who had an intermediate or secondary education level (OR: 0.55 and 0.78) were less likely to have good knowledge compared with parents who had a university degree. However, parents who earned intermediate monthly income (OR: 6.63) were more likely to have good knowledge of teething. With regards to practices used to relieve teething pain, inappropriate practices were observed regarding bottle feeding at night to soothe the child's pain (72%) and applying topical analgesics to rub the gum (72.4%). A significant positive correlation was found between the knowledge score and the practice score of both fathers and mothers (r = 0.22 and 0.13, p < 0.0001). Conclusion: A very low percentage of Saudi parents, mainly those with the highest education level and intermediate monthly income, had good knowledge of teething, which translated into appropriate practices to soothe the child's pain regardless of the parent's gender. Saudi parents should receive anticipatory guidance related to teething from all health professionals to ensure an uneventful teething period for their children.

Effect of ambient lighting conditions on tooth color quantification in cross-polarized dental photography: A clinical study.

STATEMENT OF PROBLEM: Limited data are available in the dental literature regarding the effect of ambient lighting on the consistency of color quantification in cross-polarized photography. PURPOSE: The purpose of this clinical study was to investigate the effects of ambient lighting conditions and postprocessing photograph calibration on color quantification in cross-polarized dental photography. MATERIAL AND METHODS: Twelve volunteers with intact maxillary central incisors were recruited. Cross-polarized photographs were captured under light-emitting diode (LED), fluorescent ceiling, and natural lighting. The photographs were repeated after a 1-week interval, yielding a total of 72 photographs. The average Commission Internationale de l'Eclairage L∗a∗b∗ coordinates of the right central incisor were obtained with a software program before and after calibration by using a neutral gray reference card. The color difference (ΔE) values were calculated for each participant between the repeated photographs under the change and no change in illumination both before and after calibration. A 3-way repeated measures ANOVA was used to compare these values (α=.05). RESULTS: A statistically significant 3-way interaction was found between the illuminant type, change in illumination, and calibration (P<.001); however, all the ΔE values were within a clinically acceptable threshold (ΔE≤3.7). Before calibration, when photographs were captured under no change in illumination, LED lighting was found to have a significantly lower ΔE than fluorescent (P=.008) and natural and fluorescent lightings (P=.011), but when there was a change in illumination, no significant differences (P>.05) were found. After calibration, all the ΔE values were ≤1 and significantly lower than the values before calibration (P<.001). CONCLUSIONS: Both the ambient illuminant type and change in illumination had minimal effects on ΔE. Calibration through the use of a neutral gray reference card was found to result in reduced and imperceptible color change (ΔE≤1) for all illuminant types.

Reduction of aerosols and splatter generated during ultrasonic scaling by adding food-grade thickeners to coolants: an in-vitro study.

OBJECTIVE: The effectiveness of using food-grade coolant thickener solutions on the amount of aerosols generated and splatter contamination spread distance during simulated ultrasonic scaling was examined. MATERIALS AND METHODS: The study was performed using a phantom lower jaw placed on a black box. Simulated ultrasonic scaling was performed for 2 min using four coolant solutions: distilled water (control), 2% wt. polyacrylic acid (PAA), 0.4% wt. xanthan gum (XA), and 0.4% wt. carboxymethyl cellulose (CMC). The simulation was repeated 10 times for each coolant group. The generated aerosols and droplets were quantified using a handheld particle counter, and the splatter contamination spread distance was evaluated by adding tracing fluorescent dye to the coolant reservoir supplying the scaler unit. One-way multivariate analysis of variance was performed to determine the difference among coolant groups (a = .05). RESULTS: The amount of aerosols and droplets and splatter contamination distance (p < .001) pertaining to the three food-grade coolant thickener solutions were considerably lower than those for the distilled water (control). The PAA group exhibited a significantly lower splatter contamination distance (p < .001) and a number of generated droplets (p = .031) than those of the XA group. The CMC group exhibited a significantly lower splatter contamination distance (p < .001) than that of the XA group. No statistically significant difference was observed between the PAA and CMC in terms of the three dependent variables (p > .05). CONCLUSION: The food-grade coolant thickeners could reduce the amount of generated aerosols and splatter contamination distance but not completely eliminate them. PAA and CMC solutions were more effective in reducing the aerosol/splatter during scaling compared to XA. CLINICAL RELEVANCE: Many dental procedures generate aerosols and splatter, which pose a potential risk to the patients and dental personnel, especially during the current COVID-19 pandemic.

Pediatric Obstructive Sleep Apnea: Knowledge and Attitudes of Medical and Dental Students and Fresh Graduates from Saudi Arabia.

This study aimed to assess the knowledge level and attitudes of graduating Saudi medical and dental students and fresh graduates from those faculties about pediatric obstructive sleep apnea (OSA), and the relation of their knowledge level to sociodemographic variables. In this cross-sectional study, 722 graduating students and fresh graduates were requested to answer a questionnaire pretested for validity and reliability. The data were analyzed statistically. Results revealed that medical participants scored 15.45 (out of 22), with 38% of them showing good knowledge about pediatric OSA, while dental participants scored 14.59, with 25.2% of them showing good knowledge. By regression analysis, medical participants (odds ratio (OR): 1.529) were more likely to have good knowledge than dental participants, while participants who belonged to institutions located in the central region (OR: 0.546) were less likely to have good knowledge than those from southern region institutions. In addition, participants from public institutions (OR: 0.290) were less likely to have good knowledge than those from private institutions. Regarding attitudes, medical participants scored 14.13 (out of 20), and dental participants scored 14.64. We detected a significant positive correlation between knowledge and attitude scores of dental participants. Given these findings, the knowledge level of graduating Saudi medical and dental students and fresh graduates about pediatric OSA was not optimal. The college type, institution sector, and location in the kingdom were factors associated with good knowledge. There is a need for further education and training about pediatric OSA in the undergraduate Saudi medical and dental curricula and continuing professional development programs about the topic after graduation.

Risk Factors of Early Childhood Caries Among Preschool Children in Eastern Saudi Arabia.

This study aimed to determine the risk factors of early childhood caries (ECC) among preschool children from eastern Saudi Arabia. In this cross-sectional study, 241 carers and their children from 10 daycares were recruited and asked to complete a questionnaire aimed at assessing their sociodemographic profile and oral health-related behaviors. This was followed by a dental examination of the children by two calibrated dentists. Caries status was recorded using the dmft index. Chi-square and logistic regression tests were used to analyze the data (p < 0.05). The mean dmft of the children was 4.39 (SD ± 4.25). According to logistic regression analysis, children who were bottle-fed between 7 and 12 months (Adjusted Odds Ratio (AOR): 0.110) or breastfed between 13 and 18 months (AOR: 0.028) were less likely to have ECC than those with a prolonged feeding duration (>18 months). Also, those with smoking carers (AOR: 0.176) were less likely to have ECC than those with nonsmoking carers. On the other hand, children who had working carers, mainly mothers, in the education sector (AOR: 11.105), were more likely to have ECC (p < 0.05). The risk factors associated with the presence of ECC among preschool children in eastern Saudi Arabia include the mother's occupation and the carer's smoking status, as well as feeding practices (particularly bottle feeding). These factors can be modified by encouraging carers to completely wean their children (particularly from the bottle) by 18 months of age and advising working mothers to perform tooth brushing for their children in the morning before they go to work and in the evening before the children go to bed.

Parental Reported Bullying among Saudi Schoolchildren: Its Forms, Effect on Academic Abilities, and Associated Sociodemographic, Physical, and Dentofacial Features.

AIM: To determine the prevalence of bullying, its forms, and its effect on academic abilities and school attendance, as well as associated sociodemographic, physical, and dentofacial features among Saudi schoolchildren. METHODS: This cross-sectional study recruited a sample of 1131 parents of schoolchildren 8-18 years old and requested them to complete internationally accepted questionnaires for their children. Chi-squared test and logistic regression analysis were used to analyze the data (p < 0.05). RESULTS: A majority (89.2%) of schoolchildren were bully victims. Physical bullying (48.9%) was the most common form of bullying. The youngest schoolchildren (8-11 years) and those who disliked school classes or neither liked nor hated them, as well as those who were truant from school, were more likely to be victims. In addition, those who had worse grades because of bullying and those who were very often bullied because of good grades or because they showed an interest in school were more likely to be victims. With regard to targeted physical features, teeth were the number one target, followed by the shape of the lips and strength, while tooth shape and color were the most common dentofacial targets, followed by anterior open bite and protruded anterior teeth. Boys and the youngest schoolchildren were more often subjected to bullying because of these features (p < 0.05). CONCLUSIONS: The prevalence of bullying, mainly in a physical form, was high among Saudi schoolchildren, with a negative influence on students' academic abilities. Problems related to teeth, in particular, which can be treated, were targets, mainly for boys and the youngest schoolchildren. More studies are required in Saudi Arabia to explore the issue further among schoolchildren themselves.

Fabrication of Custom Post-And-Core Using a Directly Fabricated Silicone Pattern and Digital Workflow.

This report introduces an alternative clinical and laboratory technique for the direct fabrication of a custom post-and-core pattern using poly (vinyl siloxane) (PVS) occlusal registration material, followed by a digital workflow. This technique decreases chairside time, eliminates the risk of locking the pattern into the postspace and improves accuracy of the custom post-and-core.

Knowledge of General Dental Practitioners and Specialists about Emergency Management of Traumatic Dental Injuries in Qassim, Saudi Arabia.

Context. Studies about knowledge of emergency management of traumatic dental injuries (TDIs) which affect children by general dental practitioners (GDPs) and specialists in Saudi Arabia are lacking. AIM: The aim of this cross-sectional study was to assess the knowledge level of GDPs and specialists about TDI emergency management and its relation with demographic variables in Qassim region, Saudi Arabia. Materials and Methods. A random sample of 239 GDPs and specialists was given a two-part questionnaire; the first part included demographic questions and the second part included questions related to knowledge of emergency management of luxation (intrusion and extrusion), complicated crown fracture, and avulsion injuries. Data was statistically analyzed using chi-square and ordinal logistic regression tests. The significance was set at P < 0.05. RESULTS: The mean knowledge score was 5.57 for GDPs and 6.69 for specialists (out of 12). A significant difference was observed between both groups in the management of avulsion injury. Three factors significantly improved the dentists' knowledge: gender (female), practice type (specialist), and previous experience of encountered TDIs (P < 0.05. CONCLUSIONS: GDPs and specialists in Qassim region had moderate knowledge of emergency management of TDIs. Specialists were significantly more knowledgeable than GDPs in the management of avulsion injury when compared to the rest of the injuries.