Deep learning-based approach for 3D bone segmentation and prediction of missing tooth region for dental implant planning.

Recent studies have shown that dental implants have high long-term survival rates, indicating their effectiveness compared to other treatments. However, there is still a concern regarding treatment failure. Deep learning methods, specifically U-Net models, have been effectively applied to analyze medical and dental images. This study aims to utilize U-Net models to segment bone in regions where teeth are missing in cone-beam computerized tomography (CBCT) scans and predict the positions of implants. The proposed models were applied to a CBCT dataset of Taibah University Dental Hospital (TUDH) patients between 2018 and 2023. They were evaluated using different performance metrics and validated by a domain expert. The experimental results demonstrated outstanding performance in terms of dice, precision, and recall for bone segmentation (0.93, 0.94, and 0.93, respectively) with a low volume error (0.01). The proposed models offer promising automated dental implant planning for dental implantologists.

DIGITAL FABRICATION OF COMPLETE DENTURES, COMPARED TO CONVENTIONAL METHODS, MAY OFFER A MORE COST-EFFECTIVE APPROACH WITH IMPROVED PATIENT OUTCOMES.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Digitally versus conventionally fabricated complete dentures: A systematic review on cost-efficiency analysis and patient-reported outcome measures (PROMs). Tew, In Meei, Suet Yeo Soo, and Edmond Ho Nang Pow.The Journal of Prosthetic Dentistry (2023). SOURCE OF FUNDING: No fund was received. TYPE OF STUDY/DESIGN: Systematic review.

DIGITAL SCANS, COMPARED TO CONVENTIONAL IMPRESSIONS, MAY EXPEDITE FABRICATION TIME FOR FULL-ARCH IMPLANT-SUPPORTED PROSTHESES WHILE MAINTAINING A COMPARABLE LEVEL OF MARGINAL BONE LOSS.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Clinical outcomes of digital scans versus conventional impressions for implant-supported fixed complete arch prostheses: A systematic review and meta-analysis. I. A., Spin-Neto, R., Sesma, N., & da Silva, E. V. F. The Journal of Prosthetic Dentistry (2023). SOURCE OF FUNDING: Not reported. TYPE OF STUDY/DESIGN: Systematic review with network meta-analysis of data.

The physical-mechanical properties of 3D-printed versus conventional milled zirconia for dental clinical applications: A systematic review with meta-analysis.

AIM OF STUDY: This systematic review aimed to compare the physical-mechanical properties of 3D-printed (additively manufactured (AM)) zirconia compared to conventionally milled (subtractive manufactured: SM) zirconia specimens. MATERIALS AND METHODS: A thorough search of Internet databases was conducted up to September 2023. The search retrieved studies that evaluated AM zirconia specimens and restorations regarding the physical-mechanical properties and mechanical behavior of zirconia. The main topic focused on 3Y-TZP. However, records of 4YSZ and 5YSZ were also included to gather more comprehensive evidence on additively manufactured zirconia ceramic. The quality of studies was assessed using the ROB2 tool, Newcastle Ottawa scale, and the Modified Consort Statement. Of 1736 records, 57 were assessed for eligibility, and 38 records were included in this review, only two clinical trials meet the inclusion criteria and 36 records were laboratory studies. There were no signs of mechanical complications and wear to antagonists with short-term clinical observation. SM thin specimens ≤1.5 mm showed statistically significant higher flexural strength than AM zirconia (p ≤ 0.01), while thicker specimens showed comparable outcomes (p > 0.5). The fracture resistance of dental restorations was dependent on the aging protocol, restoration type, and thickness. The bond strength of veneering ceramic to zirconia core was comparable. CONCLUSIONS: The results pooled from two short-term clinical trials showed no signs of mechanical or biological complications of additively manufactured 3Y-TZP zirconia crowns. The flexural strength might depend on the specimens' thickness, but it showed promising results to be used in clinical applications, taking into account the printing technique and orientation, material composition (yttria content), solid loading, and sintering parameters. 3D-printed restorations fracture resistance improved when adhered to human teeth. The veneering ceramic bond was comparable to milled zirconia specimens. Long-term RCTs are recommended to confirm the mechanical behavior of 3D-printed restorations.

The influence of Zircos-E® etchant, silica coating, and alumina air-particle abrasion on the debonding resistance of endocrowns with three different preparation designs.

OBJECTIVES: The study aimed to evaluate the debonding resistance of three different endocrown designs on molar teeth, using three different zirconia surface pretreatments. MATERIAL AND METHOD: Ninety human mandibular first molars were divided into three main groups: endocrowns without ferrule, with 1 mm ferrule, and with 2 mm ferrule. The subgroups were defined by their surface pretreatment method used (n = 15): 50 µm alumina air-particle abrasion, silica coating using 30 µm Cojet™ particles, and Zircos-E® etching. The endocrowns were fabricated using multilayer zirconia ceramic, cemented with self-adhesive resin cement, and subjected to 5000 thermocycles (5-55°C) before debonding. The data obtained were analyzed using a two-way ANOVA. RESULTS: All test specimens survived the thermocyclic aging. The results indicated that both the preparation design and the surface treatment had a significant impact on the resistance to debonding of the endocrowns (p < .001). The 2 mm ferrule followed by the 1 mm ferrule designs exhibited the highest debonding resistance, both were superior to the endocrown without ferrule. Zircos-E® etching and silica coating yielded comparable debonding resistance, which were significantly higher than alumina air-particle abrasion. All endocrowns demonstrated a favorable failure mode. CONCLUSIONS: All designs and surface treatments showed high debonding resistance for a single restoration. However, ferrule designs with Zircos-E® etching or silica coating may represent better clinical options compared to the nonferrule design or alumina airborne-particle abrasion. Nonetheless, further research, including fatigue testing and evaluations with different luting agents is recommended.

Chitosan-based materials for dental implantology: A comprehensive review.

Chitosan, a versatile biopolymer, has gained recognition in the discipline of dental implantology due to possessing salient properties. This comprehensive review explores the potential of chitosan in dental implants, focusing on its biocompatibility, bioactivity, and the various chitosan-based materials that have been utilized for dental implant therapy. The review also highlights the importance of surface treatment in dental implants to enhance osseointegration and inhibit bacterial biofilm formation. Additionally, the chemical structure, properties, and sources of chitosan are described, along with its different structural forms. The characteristics of chitosan particularly color, molecular weight, viscosity, and degree of deacetylation are discussed about their influence on its applications. This review provides valuable insights into the promising utilization of polymeric chitosan in enhancing the success and functionality of dental implants. This study highlights the potential applications of chitosan in oral implantology. Chitosan possesses various advantageous properties, including muco-adhesiveness, hemostatic action, biocompatibility, biodegradability, bioactivity, and antibacterial and antifungal activities, which enhance its uses in dental implantology. However, it has limited aqueous solubility at the physiological pH, which sometimes restricts its biological application, but this problem can be overcome by using modified chitosan or chitosan derivatives, which have also shown encouraging results. Recent research suggests that chitosan may act as a promising material for coating titanium-based implants, improving osteointegration together with antibacterial properties.

Clinical benefits of immediate dentin sealing: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: The clinical complications, success, and survival rates of indirect restorations delivered with the immediate dentin sealing protocol are unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to find and collect evidence on the clinical complication, success, and survival rates of indirect restorations delivered with immediate dentin sealing. MATERIAL AND METHODS: Electronic databases were searched for clinical studies on immediate dentin sealing up to December 2023, without language or time limitations. The records were included if they were clinical trials evaluating the clinical complication and survival rates of indirect restorations bonded to tooth substrate sealed immediately after preparation with suitable resin bonding. The extracted data were analyzed via Review Manager 5.4 for meta-analysis (α=.05). RESULTS: A total of 11 studies were included in this review. The clinical complication rate was lower for immediately sealed dentin than for protocols without dentin sealing. The survival rate of restorations luted with the immediate dentin sealing protocol was higher (96.4% to 100%) than that of immediate dentin sealing (81.8% to 96.7%), negatively correlated with the observation time. The intensity and incidence of postoperative sensitivity were statistically significantly lower for restorations with immediate dentin sealing than for those without dentin sealing or conventionally cemented (P<.05). CONCLUSIONS: Immediate dentin-sealed indirect restorations had fewer clinical complications and higher success and survival rates than those delivered without dentin sealing. To avoid postoperative sensitivity or reduce its intensity, dentin surfaces should be sealed immediately after preparation. More long-term randomized clinical trials are recommended to confirm these evidence-based conclusions.

Dental implant planning using artificial intelligence: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Data on the role of artificial intelligence (AI) in dental implant planning is insufficient. PURPOSE: The purpose of this systematic review with meta-analysis was to analyze and evaluate articles that assess the effectiveness of AI algorithms in dental implant planning, specifically in detecting edentulous areas and evaluating bone dimensions. MATERIAL AND METHODS: A systematic review was conducted across the MEDLINE/PubMed, Web of Science, Cochrane, and Scopus databases. In addition, a manual search was performed. The inclusion criteria consisted of peer-reviewed studies that examined the accuracy of AI-based diagnostic tools on dental radiographs for dental implant planning. The most recent search was conducted in January 2024. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to assess the quality of the included articles. RESULTS: Twelve articles met the inclusion criteria for this review and focused on the application of AI in dental implant planning using cone beam computed tomography (CBCT) images. The pooled data indicated an overall accuracy of 96% (95% CI=94% to 98%) for the mandible and 83% (95% CI=82% to 84%) for the maxilla in identifying edentulous areas for implant planning. Eight studies had a low risk of bias, 2 studies had some concern of bias, and 2 studies had a high risk of bias. CONCLUSIONS: AI models have the potential to identify edentulous areas and provide measurements of bone as part of dental implant planning using CBCT images. However, additional well-conducted research is needed to enhance the accuracy, generalizability, and applicability of AI-based approaches.

Failure and complication rates of different materials, designs, and bonding techniques of ceramic cantilever resin-bonded fixed dental prostheses for restoring missing anterior teeth: A systematic review and meta-analysis.

OBJECTIVES: The objective of this review was to assess clinical trials that have examined the materials, design, and bonding of ceramic cantilevered resin-bonded fixed dental prostheses (RBFDPs) as a potential option for replacing missing anterior teeth. The evaluation primarily focuses on the rate of restoration failure and clinical complications. MATERIALS AND METHODS: A thorough search of databases including PubMed/MEDLINE, Scopus, and the Cochrane Library, was conducted. The most recent search was performed in October 2023. Clinical studies that compared ceramic cantilevered RBFDPs with double retainers or cantilevered RBFDPs using different ceramic materials or bonding systems were included. The outcome measures considered were restoration failure and complication rates. RESULTS: Twelve studies met the eligibility criteria. The pooled data showed a statistically significant decrease in complication events when using cantilever designs compared with double retainer designs (p < 0.05); however, there were no differences found between the two designs in terms of restoration failure. The complication and failure rate of cantilever RBFDPs did not show a statistically significant difference with or without ceramic primer application before luting with phosphate monomer-containing luting resin (p > 0.05). CONCLUSIONS: Ceramic cantilevered RBFDPs have lower complication rates compared with those with double retainers. The use of a ceramic primer prior to luting composite resin for ceramic cantilevered RBFDPs decreases the occurrence of complications and failures, although this effect was not statistically significant. Additional research is required to confirm these findings. Glass ceramic cantilever RBFDPs showed a decrease in success after 6 years, requiring ongoing monitoring, but both zirconia and glass-infiltrated alumina cantilever RBFDPs have demonstrated durability with excellent long-term success and survival rates for up to 10 and 15 years. CLINICAL SIGNIFICANCE: Cantilever ceramic RBFDPs in the anterior region are a less invasive and valuable treatment option, providing good esthetic results.

Clinical survival and complication rate of ceramic veneers bonded to different substrates: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Evidence on the long-term clinical assessment and longevity of ceramic veneers bonded to different substrates is limited. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the effect of various substrates, including enamel, dentin, or an existing composite resin restoration, on the clinical survival and complication rates of ceramic veneers. MATERIAL AND METHODS: The PubMed, Scopus, and the Cochrane Library electronic databases were searched, and related journals were hand searched without time or language restrictions to identify clinical trials that compared the survival rate and clinical complication rates when bonding ceramic veneers to different tooth substrates. The success rate of the included participants was estimated by the number of veneers that did not require a clinical intervention, and the survival rate by all veneers that did not fail absolutely. The risk difference (RD) with 95% confidence intervals (CIs) for dichotomous outcomes was used to quantify the intervention effect. RESULTS: Of 973 screened articles, 6 clinical studies were included. The survival and success rates varied depending on the bonding substrate. Enamel-bonded veneers had almost perfect rates of survival (99% with a range of 98% to 100%) and success (99% with a range of 98% to 100%). Veneers bonded to composite resin or surfaces with minimal dentin exposure had slightly lower survival rates (94% with a range of 91% to 97% and 95% with a range of 91% to 100%, respectively) and success rates (70% with a range of 60% to 80% and 95% with a range of 90% to 99%). Severe dentin exposure significantly decreased both survival rates (91% with a range of 84% to 98%) and success rates (74% with a range of 64% to 85%). The combined findings suggested that ceramic veneers bonded to enamel had fewer clinical complications (RD: -0.04; 95% CI: -0.09 to 0.02) and lower failure rates (RD: -0.13; 95% CI: -0.32 to 0.07) compared with those bonded to exposed dentin. Additionally, veneers attached to teeth with minimal dentin exposure were significantly less likely to require clinical interventions (RD: -0.16; 95% CI: -0.31 to -0.01) and had a reduced incidence of failure (RD: -0.08; 95% CI: -0.17 to 0.01) compared with those with severe dentin exposure. CONCLUSIONS: Ceramic veneers bonded to enamel showed higher survival and success rates with lower clinical incidences of complications and failure than those bonded to dentin or teeth with existing composite resin restorations.

IMMEDIATE IMPLANT PLACEMENT WITH A SIMULTANEOUS BONE AUGMENTATION OF THE GAP-FILLING SITES CAN POTENTIALLY DECREASE BONE LOSS COMPARED WITH AUGMENTED SITES EXHIBITING GAPS WITH BONY DEFECTS.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Marginal bone level change of immediately restored implants with simultaneous guided bone regeneration: A systematic review. Lin, X., Yu, X., Wang, F., & Wu, Y. Clinical Implant Dentistry and Related Research 2023. SOURCE OF FUNDING: CAMS Innovation Fund for Medical Sciences (CIFMS), Grant/Award Number: 2019-I2M- 5-037; Clinical Research Plan of SHDC, Grant/Award Number: SHDC2020CR3049B; Huangpu District Industrial Support Fund, Grant/Award Number: XK2020014; Research Discipline Fund, Grant/Award Number: KQYJXK2020. TYPE OF STUDY/DESIGN: Systematic review.

3D-printed versus conventionally milled zirconia for dental clinical applications: Trueness, precision, accuracy, biological and esthetic aspects.

OBJECTIVES: This systematic review aimed to compare the clinical outcome, internal gap, trueness, precision, and biocompatibility of 3D-printed (AM) compared to milled (SM) zirconia restorations. DATA SOURCE: A thorough search of Internet databases was conducted up to September 2023. The search retrieved studies compared AM zirconia to SM zirconia restorations regarding clinical outcome, fit, trueness, precision, and biocompatibility. STUDY SELECTION: Of 1736 records, only 59 were screened for eligibility, and 22 records were included in this review. The quality of studies was assessed using the revised Cochrane risk-of-bias tool (ROB2), and the Modified Consort Statement. One clinical study exhibited a low risk of bias. All laboratory studies revealed some bias concerns. Short-term observation showed 100 % survival with no signs of periodontal complications. 3D-printed zirconia crowns showed statistically significant lower ΔE and a better match to adjacent teeth (p ≤ 0.5). The fit, trueness, and precision vary with the printing technique and the tooth surface. CONCLUSIONS: 3D-printed zirconia crowns provide better aesthetic color and contour match to adjacent natural teeth than milled crowns. Both 3D printing and milling result in crowns within the clinically acceptable internal and marginal fit. Except for nanoparticle jetting, the marginal gap of SM crowns was smaller than AM crowns, however, both were clinically acceptable. Laminate veneers might be more accurately produced by 3D printing. 3D-printed axial surface trueness was better than milled axial surfaces. Long-term RCTs are recommended to confirm the clinical applicability of 3D-printed restorations. CLINICAL SIGNIFICANCE: Internal fit and gap, precision, and trueness are fundamental requirements for successful dental restorations. Both techniques produce restorations with clinically acceptable marginal and internal fit. Axial surfaces and narrow or constricted areas favored 3D-printed than conventionally milled zirconia.

Practical applications of robots in prosthodontics for tooth preparation and denture tooth arrangement: A scoping review.

STATEMENT OF PROBLEM: With the increasing interest in using robots in dentistry and the widespread dissemination of information on this topic and its applications, a comprehensive review of robot applications in prosthodontics is needed. PURPOSE: The purpose of this scoping review was to assess the current status of prosthodontic robotic applications, their achievements to date, and the barriers hindering their broader adoption and further advancement. MATERIAL AND METHODS: The checklist for Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) was used to conduct this review. A comprehensive search methodology was developed to identify relevant studies on the use of robots in prosthodontic procedures in the PubMed, Scopus, Web of Science, and Google Scholar databases. The inclusion criteria were studies that specifically outlined the application of robots in the field of prosthodontics. RESULTS: Eighteen relevant studies were found. Of these, 10 studies focused on assessing the effectiveness of robotic systems through in vitro testing using phantom models for tooth preparation. These studies specifically explored the processes involved in creating complete crowns and veneers. The remaining 8 studies investigated the use of robotics in tooth alignment, with a specific focus on complete dentures. CONCLUSIONS: Robots have the potential to improve precision and accuracy in prosthetic dentistry. However, clinical studies are needed to confirm the widespread use of robots in prosthodontics, as their clinical application is still in its early stages.

Clinical assessment of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. A randomized controlled clinical trial.

OBJECTIVES: To evaluate the peri-implant marginal bone loss (MBL) and prosthodontic complications of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. MATERIAL AND METHODS: 28 participants with edentulous maxillary arches were randomly selected and enrolled in two equal groups; Group I conventional impression group (CIG) and Group II Digital impression group (DIG). All patients were rehabilitated with maxillary screwretained implant prosthesis retained by 6 implants. Peri-implant MBL and prosthodontic complications and were registered at 6, 12, and 24 months (m). Data was collected and statistically analyzed. RESULTS: Regarding the effect of time, there was a statistically significant increase in MBL at 6, 12 and 24 m follow-up periods (P<.001). As for the effect of groups, there was no statistically significant difference in MBL between CIG and DIG at 6, 12 and 24 m where P value was 0.083, 0.087 and 0.133 respectively. Prosthetic complications were recorded 19 times in the conventional group and 12 times in the digital group with no significant difference between both groups (P=.303). CONCLUSION: Digital full -arch implant impression is a reliable impression technique and may represent an alternative to conventional impression technique in the fabrication of maxillary screw-retained implant prosthesis.

3D-printed intracoronal restorations, occlusal and laminate veneers: Clinical relevance, properties, and behavior compared to milled restorations; a systematic review and meta-analysis.

OBJECTIVES: To assess the feasibility of producing 3D-printed intracoronal restorations, thin and ultrathin veneers, and to compare their mechanical behavior, accuracy, biological, and stain susceptibility to the currently applied milled restorations. MATERIALS AND METHODS: The databases were comprehensively searched for relevant records up to January 2024 without language restrictions. All studies that assessed 3D-printed partial coverage restorations including inlays, onlays, laminate, and occlusal veneers were retrieved. RESULTS: The web search yielded a total of 1142 records, with 8 additional records added from websites at a later stage. Only 17 records were ultimately included in the review. The included records compared 3D-printed; alumina-based- and zirconia ceramics, lithium disilicate ceramics, polymer infiltrated ceramics, polyetheretherketone (PEEK), resin composites, and acrylic resins to their CNC milled analogs. The pooled data indicated that it is possible to produce ultrathin restorations with a thickness of less than 0.2 mm. 3D-printed laminate veneers and intracoronal restorations exhibited superior trueness, as well as better marginal and internal fit compared to milled restorations (p < 0.05). However, it should be noted that the choice of materials and preparation design may influence these outcomes. In terms of cost, the initial investment and production expenses associated with 3D printing were significantly lower than those of CNC milling technology. Additionally, 3D printing was also shown to be more time-efficient. CONCLUSIONS: Using additive manufacturing technology to produce restorations with a thickness ranging from 0.1 to 0.2 mm is indeed feasible. The high accuracy of these restorations, contributes to their ability to resist caries progression, surpassing the minimum clinical threshold load of failure by a significant margin and reliable adhesion. However, before 3D-printed resin restorations can be widely adopted for clinical applications, further improvements are needed, particularly in terms of reducing their susceptibility to stains. CLINICAL SIGNIFICANCE: 3D-printed intracoronal restorations and veneers are more time and cost-efficient, more accurate, and could provide a considerable alternative to the currently applied CNC milling. Some limitations still accompany the resin materials, but this could be overcome by further development of the materials and printing technology.

The Influence of Ferrule Design and Pulpal Extensions on the Accuracy of Fit and the Fracture Resistance of Zirconia-Reinforced Lithium Silicate Endocrowns.

The study aimed to assess the marginal, axial, and internal adaptation, as well as the fracture resistance of zirconia-reinforced lithium silicate (ZLS) endocrowns with varying pulpal inlay extensions and marginal geometry. Sixty extracted maxillary first molar teeth were divided into six groups (n = 10) according to pulpal inlay extension and marginal configuration. The first three groups (J2, J3, and J4) utilized prepared teeth for endocrowns without ferrule design and 2 mm, 3 mm, and 4 mm pulpal extensions, respectively. The second three groups (F2, F3, and F4) utilized prepared teeth with 1 mm shoulder margins and 2 mm, 3 mm, and 4 mm pulpal extensions. The endocrowns were fabricated from ZLS blocks using CAD/CAM milling technology. After cementation, the specimens underwent thermal aging for 5000 cycles and were evaluated for marginal adaptation. Using a universal testing machine, the fracture resistance was tested under quasistatic loading (1 mm/min). Two-way ANOVA and the Tukey's post hoc test were employed for data analysis (p ≤ 0.05). The results of this study revealed that endocrowns without ferrule exhibited superior fracture strength than a 1 mm ferrule design p < 0.05, irrespective of the inlay depth. All designs with and without ferrule and all inlay depths showed clinically acceptable marginal and internal fit. The conventional endocrown design without ferrule and 2 mm inlay depth showed the lowest surface gap. The pulpal surface showed the highest discrepancy among all groups compared to the other surfaces. Endocrowns without ferrule are more conservative and have higher fracture strength than 1 mm ferrule designs; extending the inlay depth showed a significant increase in fracture resistance of the 1 mm ferrule design, but not for the conventional design without ferrule and 2 mm inlay depth. All groups exhibited a high auspicious fracture strength value for molar endocrown restorations.

Behaviors, hygiene habits, and sources of care among removable complete and partial dentures wearers: A multicenter cross-sectional study.

OBJECTIVES: There is a lack of data regarding the hygiene practices and sources of care among individuals in Yemen who wear removable complete and partial dentures. The purpose of this study was to explore the behaviors, hygiene habits, and sources of care information among patients who utilize complete and partial dentures in Yemen. MATERIALS AND METHODS: A descriptive cross-sectional research design was utilized, and a sample of 217 consecutive participants who wore removable complete and/or partial dentures were enlisted. A questionnaire was employed to collect data on demographic information, educational attainment, denture habits, denture cleaning practices, and encountered difficulties. Statistical analysis was conducted using SPSS software, and significance was determined using chi-square tests, with a significance level of .05. RESULTS: The data analysis revealed that a majority of the participants were male (72.4%) and had an average age of 65.14 years. Fifty-three percent of the participants wore partial dentures, while 34.6% wore complete dentures. Only 6.5% of the participants wore both complete and partial dentures, and 6% wore overdentures. The majority of participants (88.47%) had dentures made of acrylic material. Additionally, 43% of participants wore dentures while sleeping, and 61.3% stored their dentures in dry places without a water-filled container when not in use. The most commonly reported cleaning methods were water only (24.4%), followed by water and soap (19.4%). Furthermore, a large portion of the participants (59.4%) received denture care information from dentists. However, the majority (59%) did not visit a dentist for regular denture maintenance or any denture-related issues. The data analysis did not reveal any significant association between age or education level and denture cleaning methods. CONCLUSION: This cross-sectional survey provides insight into the hygiene knowledge and practices of removable denture wearers in Yemen. The findings underscore the necessity for enhanced oral hygiene education and awareness within this population. The study offers valuable insights for oral health professionals to design targeted interventions and educational initiatives aimed at promoting proper denture care and maintenance. These efforts have the potential to enhance the oral health and overall well-being of removable denture wearers.

Quantitative and qualitative 3D analysis of mandibular lingual concavities: Implications for dental implant planning in the posterior mandible.

OBJECTIVE: The purpose of this study is to investigate the type of ridge (degree of angulation of the lingual concavity) and the buccolingual dimensions in the area of the first and second molars in both genders of different ages and how this will affect implant placement in the posterior mandible. MATERIALS AND METHODS: This retrospective cross-sectional study comprised cone beam computed tomography images of 150 dental patients (75 males and 71 aged ≥30). The following were measured/reported: type (morphology) of the ridge (convex [C], parallel [P], or undercut [U]), buccolingual width at the base and the crest of the ridge, and ridge height. The concavity angle, depth, and length of the U-shaped ridge were measured too. RESULTS: The prevalence of type U ridge ranged from 32.7% in the first molar region to 62.7% in the second molar region. Almost all measurements and ridge type distributions were comparable amongst the age groups (p > .05). Very few significant differences were found when comparing #36 versus #37 and #46 versus #47 teeth, with no differences in the distribution of the ridge types (p > .05). Quite the inverse, all measurements were statistically different when comparing #36 versus #37 and #46 versus #47 teeth, and type U ridge was more frequent in second molar compared to the first molar regions, respectively (p < .05). Many measurements were statistically higher in females; the inverse was true for a few measurements (p < .05). Type U ridge in #36 and #37 was found more frequently among males (p < .001). In contrast, the ridge types in #37 and #47 were not statistically different gender-wise. CONCLUSIONS: The U type of ridge was more prevalent in the investigated population, encountered more frequently in the second molars generally and in the first molars of males than females. Most posterior mandibular measurements are similar age- and side-wise but seem different gender- and tooth-wise.

Effect of ceramic materials and tooth preparation design on computer-aided design and computer-aided manufacturing endocrown adaptation and retentive strength: An in vitro study.

OBJECTIVES: To evaluate how various tooth preparation designs impact the adaptation-both at the margins and internally-and the retentive strength of computer-aided design and computer-aided manufacturing (CAD/CAM) produced endocrowns. MATERIALS AND METHODS: 60 extracted human mandibular first molars were endodontically treated and assigned into three groups (n = 20) according to the tooth preparation design: Group N: butt joint design, Group F and F1 received 1- and 2-mm circumferential ferrule preparation, respectively. Endocrowns were milled using either lithium disilicate glass-ceramic (IPS emax ceramic) or monolithic zirconia. The internal and marginal adaptation of the endocrowns were evaluated using the replica technique. After cementation, the endocrowns of all test groups were dislodged axially at 0.5 mm/min using a universal testing machine. A 2-way ANOVA and the independent samples t-test (α = .05) were performed to statistically analyze the data. RESULTS: The effect of changing the design of the tooth preparation (butt joint, ferrule) on the marginal and internal gap was shown to be statistically significant (p < .05); the lower gap values were recorded at the axial followed by cervical, marginal, and pulpal floor walls in both ceramic groups regardless of the teeth preparation design. The ANOVA test revealed similar average removal forces and stresses for the two types of tested ceramic materials. CONCLUSION: IPS emax ceramic adapted better than monolithic zirconia ceramic, regardless of the preparation design. Ferrule preparation design is more retentive than butt joint preparation, regardless of the type of ceramic material used.

Comprehensive analysis of the maxillary esthetic zone for immediate implant placement using cone beam computed tomography: A study of 352 maxillary images.

STATEMENT OF PROBLEM: Previous studies have examined the maxillary esthetic zone for immediate implant placement, but these studies had small sample sizes and did not investigate multiple parameters. PURPOSE: The purpose of this cross-sectional study was to use cone beam computed tomography (CBCT) to evaluate the sagittal root position (SRP), alveolar bone concavity, labial bone perforation (LBP), and tooth-ridge angle in the maxillary anterior teeth region. MATERIAL AND METHODS: A total of 352 CBCT images of patients (180 men and 172 women) who visited the dental hospital between 2018 and 2023 were analyzed. The sample included 2112 anterior maxillary teeth. SRP, alveolar bone concavity, tooth ridge angle, and LBP were assessed using virtual implant simulation. The data were analyzed by using chi-squared and kappa tests to analyze distributions and agreement, respectively, dependent and independent t-tests to assess sex and tooth-specific differences, and the Spearman correlation test to explore potential correlations (α<.05). RESULTS: The CBCT images revealed that the majority of SRP were in Class I (85.4%), with smaller percentages in Class II (12.5%) and Class IV (2.3%); Class III was the least common (1%). The canine exhibited the most significant alveolar bone concavity angle average (149.14 ±6.35 degrees), followed by the lateral incisor (142.32 ±8.7 degrees). The canines had the highest occurrence of LBP (63.1%) (P<.01). Women had a higher frequency of labial bone perforation and deeper alveolar bone concavities than men (P<.01). CONCLUSIONS: The findings of this study indicate that careful assessment and planning are necessary for immediate implant placement in the maxillary anterior region. The significant occurrence of LBP highlights the importance of thorough planning and evaluation to avoid surgical mishaps and complications which may necessitate bone grafting and result in added costs and time. Special attention should be given to women and the canine area.