Evaluation of open-face maxillary complete denture for patients with prominent premaxilla: a crossover study.

BACKGROUND: The establishment of good facial esthetics is one of the main objectives of complete denture construction. Unfortunately, it may be the caused issue for patients having a prominent premaxilla due to excessive lip support by the labial flange of the maxillary denture. Open-face dentures (OFD) may suggest suitable prosthetic management for these patients. However, clinical evidence regarding the efficiency of OFD is scarce. METHODS: A total of 38 completely edentulous participants having prominent premaxilla and skeletal class I Angle's classification were enrolled in this study. Each participant received a mandibular complete denture and 2 opposing maxillary dentures; conventional (CD) and open-face (OFD). On the day of denture insertion, the participants were divided into 2 groups; CD-OFD and OFD-CD where CD-OFD group was instructed to use the mandibular denture and the maxillary CD for 3 months and then to use the maxillary OFD for another 3 months after a wash-out period of 2 weeks. While group OFD-CD was instructed to use the mandibular denture and the maxillary OFD for 3 months then to use the maxillary CD for another 3 months after a wash-out period of 2 weeks. The dislodging force of the maxillary dentures was evaluated using the universal testing machine and the patient perception of retention, esthetics, and comfort was evaluated using the Visual Analogue Scale (VAS). Evaluation was carried out 1 day, 1 month, and 3 months after denture insertion. The Student t-test was used to compare the 2 maxillary dentures and the intervals for each denture were compared by using the ANOVA test with repeated measures followed by a Post Hoc test (adjusted Bonferroni) for pairwise comparison. RESULTS: The significance of the obtained results was judged at the 5% level (P value). The dislodging force and patient perception of retention did not show significant differences between the 2 dentures, while the perception of esthetics showed significant differences throughout the follow-up period. Perception of comfort showed an insignificant difference only at the 3-month interval. CONCLUSIONS: Open-face maxillary dentures can be a suitable alternative for patients with prominent premaxilla to achieve satisfactory retention, aesthetics, and comfort.

Japanese Wooden Plate Denture as Origin of Suction Retention.

The modern theory of complete denture retention using suction was applied to wooden plate dentures in Japan from the first half of the 16th century, which is an astonishing achievement since it was clinically applied in North America and Europe in the latter half of the 19th century nearly 300 years later. Wooden dentures are unique to Japan resulting from skilled Japanese craftsmanship and are not found in other countries. We comprehensively reviewed reports on wooden plate dentures, analyzed 145 complete and partial dentures, and discussed their history. Japanese wooden plate dentures are mainly made of box wood, and artificial teeth are made of pagodite, ivory, and natural teeth. Small nails were driven into the molar region. Many existing dentures revealed attrition on the occlusal faces, thereby indicating that the wearers were able to masticate sufficiently. Wooden plate dentures have been used for 400 years in the early 20th century. Although Japanese wooden dentures have not been mentioned in the history of dentistry in Western literature, they comprise an important part of the history of denture development.

Effect of different fabrication workflows on the passive fit of screw-retained bar splinting two interforaminal implants: a parallel blinded randomised clinical trial.

BACKGROUND: To clinically compare the effect of the conventional and the digital workflows on the passive fit of a screw retained bar splinting two inter-foraminal implants. METHODS: The current study was designed to be a parallel triple blinded randomised clinical trial. Thirty six completely edentulous patients were selected and simply randomized into two groups; conventional group (CG) and digital group (DG). The participants, investigator and outcome assessor were blinded. In the group (CG), the bar was constructed following a conventional workflow in which an open top splinted impression and a lost wax casting technology were used. However, in group (DG), a digital workflow including a digital impression and a digital bar milling technology was adopted. Passive fit of each bar was then evaluated clinically by applying the screw resistance test using the "flag" technique in the passive and non passive situations. The screw resistance test parameter was also calculated. Unpaired t-test was used for intergroup comparison. P-value < 0.05 was the statistical significance level. The study protocol was reviewed by the Research Ethics Committee in the author's university (Rec IM051811). Registration of the clinical trial was made on clinical trials.gov ID NCT05770011. An informed consent was obtained from all participants. RESULTS: Non statistically significant difference was denoted between both groups in all situations. In the passive situation, the mean ± standard deviation values were 1789.8° ± 20.7 and1786.1° ± 30.7 for the groups (CG) and (DG) respectively. In the non passive situation, they were 1572.8° ± 54.2 and 1609.2° ± 96.9. Regarding the screw resistance test parameter, they were 217° ± 55.3 and 176° ± 98.8. CONCLUSION: Conventional and digital fabrication workflows had clinically comparable effect on the passive fit of screw retained bar attachments supported by two dental implants.

Assessment of a novel electrochemically deposited smart bioactive trabecular coating (SBTC®): a randomized controlled clinical trial.

OBJECTIVES: A randomized controlled clinical trial of dental implants was conducted to compare the clinical properties of a novel electrochemically deposited calcium phosphate coating to those of a common marketed surface treatment. MATERIAL AND METHODS: Forty implants of the same brand and type were placed in 20 fully edentulous participants requiring mandibular implantation. The two study groups were defined by the surface treatment of the implants. 20 implants in the control group were coated via a commercial electrochemical surface treatment that forms a mixture of brushite and hydroxyapatite, while the remaining 20 in the test group were coated with a novel electrochemical Smart Bioactive Trabecular Coating (SBTC®). A split-mouth design was employed, with each participants receiving one control implant in one mandibular side and a test implant in the other. To mitigate potential operator-handedness bias, control and test implants were randomly assigned to mandibular sides. All cases underwent digital planning, implant placement with a static surgical guide, and participants received locator-anchored full-arch dentures. The primary outcome was implant stability (measured using Osstell ISQ) assessed at insertion, loading, and then 3 months, 9 months, and 2 years post-insertion. The secondary outcome was bone level change (in millimeters) over the 2-year observation period. Oral health-related quality of life (OHRQL) was monitored using the OHIP-14 questionnaire. Complications and adverse events were recorded. RESULTS: Successful osseointegration and implant stability were achieved in all cases, allowing loading. ISQ values steadily increased throughout the observation period. While no significant differences were observed between the SBTC® and control coatings, the test group exhibited a higher ISQ gain. Bone resorption was somewhat lower in the SBTC® but not significantly so. Patients' OHRQL significantly improved after denture delivery and remained stable throughout the follow-up. No complications or adverse events were observed. CONCLUSIONS: Based on the study results, we conclude that the new surface treatment is a safe alternative to the widely used control surface, demonstrating similar osseointegrative properties and time-dependent bone level changes. Further research may explore the broader implications of these findings. TRIAL REGISTRATION: The study is registered on clinicaltrials.gov under the identifier ID: NCT06034171.

Preserving Natural Teeth to Maintain Oral Health.

Oral health is an important component of general health, and oral disease is one of the most common human diseases that not only affects oral health and quality of life, but is also closely associated with overall health. Natural teeth are important functional organs and are crucial to oral functions and maintaining a healthy life. The Chinese Stomatological Association (CSA) has released this position statement on "Preserving Natural Teeth to Maintain Oral Health", which is one of the most important achievements of the 2021 to 2023 CSA Annual Congress themed "Healthy Mouth, Protecting Natural Teeth", advocating that everyone should take effective measures to protect their natural teeth, maintain oral health and promote general health.

Wearing Sports Mouthguards to Prevent Oral and Maxillofacial Trauma.

The theme of the academic annual conferences held by the Chinese Stomatological Association from 2021 to 2023 was "Protecting Natural Teeth to Maintain Oral Health" and coincided with the 24th Winter Olympic Games that took place in Beijing in 2022, and thus prevention of oral and maxillofacial trauma once again attracted the attention of stomatological experts and the public. The incidence of oral and maxillofacial trauma caused by sports is around 25% to 34%1-5, and varies based on the type of sport and other factors, such as age, sex and the skill level of the participants. The risk of oral and maxillofacial trauma is extremely high in high-confrontation and high-speed sports, especially for children and adolescents. Wearing sports mouthguards when participating in sport is an effective way to prevent and reduce the incidence of oral and maxillofacial trauma in such sports, and is the simplest and most practical method of doing so. Sports have developed and gained in popularity significantly in China in recent years, but the awareness and use of sports mouthguards are low. Based on the above background, the Chinese Stomatological Association advocates that athletes and sport participants should wear mouthguards in various confrontational and high-speed sports, and calls on dental practitioners and sports-related organisations to actively support the popularisation and application of sports mouthguards to prevent or alleviate oral and maxillofacial trauma and to raise awareness and increase knowledge of methods to protect natural teeth.

[Interaction between implants and natural teeth in patients with severe periodontitis:a retrospective study].

Objective: To evaluate the clinical outcomes after implant restoration in the posterior region of severe periodontitis patients and to investigate the factors of natural tooth affecting the implant from the perspective of improving natural periodontal health, which may provide a reference for clinical practice. Methods: Fifty-three patients with severe periodontitis who visited the Department of Periodontology at the Affiliated Stomatological Hospital of China Medical University from June 2014 to June 2023 and completed posterior implant treatment with single crown were included, among which were 16 males and 37 females, aged (52.2±8.0) years old, with a total of 136 implants, 135 adjacent natural teeth in the edentulous area. We retrospectively compared the changes of probing depth (PD), bleeding on probing (BOP) and tooth mobility (TM) before and after implant placement. Besides, we explored the effects of the natural periodontal status on PD, BOP and marginal bone loss (MBL) of the implant at the last follow-up examination by univariate analysis and multivariate analysis. Results: Fifty-three patients were followed up for (44.5±14.1) months in average, with longest interval of (8.3±2.7) months. The PD of adjacent natural teeth in the edentulous area improved from 4.3 (3.6, 4.6) mm before implantation to 3.6 (3.2, 4.0) mm in the last review (P<0.01), while the proportion of BOP (+) improved from 69.6% (94/135) before implantation to 46.7% (63/135) in the last review (P<0.01). The proportion of teeth with mobility≥Ⅱ decreased from 15.6% (21/135) to 5.9% (8/135) (P<0.01). The percentage of natural teeth with PD≥4 mm in the same segment improved from 21.0% (13.3%, 26.0%) before implantation to 18.0% (12.0%, 25.0%) in the last review (P<0.05). The BOP (+)% improved from 29.0% (24.0%, 35.0%) before implantation to 23.0% (18.0%, 31.0%) in the last review (P<0.05), and the number of teeth with mobility≥Ⅱ decreased from 0.0 (0.0, 1.0) to 0.0 (0.0, 0.8) (P<0.05). The functional tooth unit score of full natural teeth increased from 8.0 (6.0, 10.0) points before implantation to 12.0 (12.0, 12.0) points in the last review (P<0.01). PD≥4 mm % increased from 11.0% (6.0%, 25.0%) before implantation to 13.0% (3.0%, 21.0%) in the last review (P<0.05) and there was no significant differences in BOP (+)% [(17.0±9.7) % vs (14.6±7.2) %, P>0.05]. The number of teeth with mobility≥Ⅱ decreased from 1.0 (0.0, 1.8) to 0.0 (0.0, 0.8) (P<0.05). Conclusions: Under the premise of regular supportive care, implant restorative treatment in the posterior region of severe periodontitis patients is helpful to improve the PD, BOP and TM of remaining natural teeth. Besides, the stages and grades of periodontitis at initial diagnosis can affect the PD and BOP of implants.

Influence of intraoral scanning coverage on the accuracy of digital implant impressions - An in vitro study.

OBJECTIVES: To evaluate the influence of intraoral scanning coverage (IOSC) on digital implant impression accuracy in various partially edentulous situations and predict the optimal IOSC. METHODS: Five types of resin models were fabricated, each simulating single or multiple tooth loss scenarios with inserted implants and scan bodies. IOSC was subgrouped to cover two, four, six, eight, ten, and twelve teeth, as well as full arch. Each group underwent ten scans. A desktop scanner served as the reference. Accuracy was evaluated by measuring the Root mean square error (RMSE) values of scan bodies. A convolutional neural network (CNN) was trained to predict the optimal IOSC with different edentulous situations. Statistical analysis was performed using one-way ANOVA and Tukey's test. RESULTS: For single-tooth-missing situations, in anterior sites, significantly better accuracy was observed in groups with IOSC ranging from four teeth to full arch (p < 0.05). In premolar sites, IOSC spanning four to six teeth were more accurate (p < 0.05), while in molar sites, groups with IOSC encompassing two to eight teeth exhibited better accuracy (p < 0.05). For multiple-teeth-missing situations, IOSC covering four, six, and eight teeth, as well as full arch showed better accuracy in anterior gaps (p < 0.05). In posterior gaps, IOSC of two, four, six or eight teeth were more accurate (p < 0.05). The CNN predicted distinct optimal IOSC for different edentulous scenarios. CONCLUSIONS: Implant impression accuracy can be significantly impacted by IOSC in different partially edentulous situations. The selection of IOSC should be customized to the specific dentition defect condition. CLINICAL SIGNIFICANCE: The number of teeth scanned can significantly affect digital implant impression accuracy. For missing single or four anterior teeth, scan at least four or six neighboring teeth is acceptable. In lateral cases, two neighboring teeth may suffice, but extending over ten teeth, including contralateral side, might deteriorate the scan.

Oral health-related quality of life and reasons for discontinuing partial removable dental prosthesis usage: a cross-sectional study with one to seven years of follow-up.

BACKGROUND: In partial edentulous individuals, a partial removable dental prosthesis (PRDP) is a common dental replacement option to improve oral function and quality of life. However, some patients discontinue using their denture over time. The aim of this study was to determine the prevalence and characteristics of partial edentulous patients who no longer wear their dentures, explore their reasons, and assess their oral health-related quality of life (OHRQoL). METHODOLOGY: This cross-sectional study, conducted at Chulalongkorn University Dental School from 2013 to 2019, involved patients who received PRDP treatment. They were contacted via phone calls and asked about their denture usage. Eligible participants were patients who had stopped or rarely used their PRDPs. Data on oral status, health insurance, and PRDP variables were collected from hospital records. Telephone interviews were conducted to collect the initial reasons for seeking PRDP treatment, reasons for discontinuation, desire for a new PRDP, and OHRQoL. The Oral Impacts on Daily Performances index was used to assess the OHRQoL. The score was dichotomized into the absence or presence of oral impacts. Chi-square tests and multivariable binary logistic regression were employed to determine the associations between oral impacts and various factors in the participants who discontinued PRDP usage. RESULTS: Among the 975 contacted participants, 175 (17.9%) discontinued using their PRDPs. Most of these individuals had at least 20 remaining natural teeth and/or 4 posterior occluding pairs. The primary initial reason for seeking PRDP treatment was often based on a dentist's suggestion. Although many participants reported no impact on OHRQoL and did not express the need for new PRDPs, those experiencing oral impacts were more likely to seek replacements. CONCLUSIONS: With up to 7 years follow-up duration, individuals with partial edentulism and sufficient remaining functional dentition without oral impacts were more inclined to discontinue PRDP usage. Those with maxillary anterior teeth loss were less likely to discontinue using their PRDP. The primary initial reason for seeking PRDP treatment was often a dentists' suggestion. However, the individuals reporting oral impacts expressed their needs for new denture replacements. This highlights the significance of incorporating patient needs and preferences in prosthodontic decision-making.

Expediting the Rehabilitation of Severely Resorbed Ridges Using a Combination of CAD-CAM and Analog Techniques: A Case Report.

With the life expectancy increasing, there is a growing need for prosthetic dental treatments to restore the oral health, function, and quality of life of edentulous patients. Presently, only a few articles are available describing the oral rehabilitation of patients with severely resorbed ridges with milled complete dentures. This clinical case report provides a straightforward protocol consisting of a combination of analog and digital techniques for the rehabilitation of edentulous patients with severely resorbed ridges with milled fixed and removable complete dentures. This technique permits the minimization of the number of appointments, improves patient comfort, allows for the digital archiving of important clinical data, and permits the manufacture of prostheses with improved mechanical properties. These favorable outcomes were achieved by using the patient's existing PMMA complete denture as a custom tray for a final impression with light-bodied Polyvinylsiloxane. Subsequently, the resulting models were digitized, and a digital complete denture was designed and manufactured in an expedited manner using CAD-CAM techniques. Therefore, this case report highlights the potential of CAD/CAM technology to predictably restabilize oral functions and improve patients' quality of life.

Digital planning and surveying for a rotational path removable partial denture: a case report.

Digital technology has been applied to the planning and manufacture of removable partial dentures (RPDs), reducing the complexity of RPD treatment as well as the number and duration of clinical and laboratory steps. However, there is a lack of information regarding digital planning and surveying for rotational path RPDs. This article presents a case report of a digital diagnostic wax-up and survey for a rotational path RPD performed with prosthetic design software. The virtual diagnostic closure tool made it possible during the case study stage to visualize the edentulous spaces and simulate the preparations necessary for the restoration of occlusal and esthetic harmony. The virtual survey determined the dual-axis path of insertion and removal for the rotational path RPD based on the 4 major influencing factors: guiding planes, retentive undercuts, interferences, and esthetics. In this case, digital planning and surveying for a rotational path RPD were an effective means of esthetic and biomechanical analysis and allowed for minimal preparation of the abutment teeth.

Novel complete-arch pillar system (CAPS) to register implant position and maxillomandibular relationship in one single visit.

OBJECTIVES: This article presents a novel complete-arch pillar system (CAPS) to register implant position and maxillomandibular relationship in one single visit for implant-supported fixed complete dental prostheses (IFCDPs). MATERIAL AND METHODS: The novel system presents a 3-unit toolset comprising intraoral scan bodies (ISBs), lateral pillar attachments (LPAs) and occlusal pillar attachments (OPAs). A 2-stage single visit workflow by an intraoral scanner (Trios 5) was introduced. The first stage "Screw-Scan-Done" was used to describe complete-arch intraoral implant scanning using LPAs. The second stage "Screw-Occlude-Done" involved virtual occlusal recording using OPAs. Two patients with one single edentulous arch were selected for this study. In the first patient, 6 bone level implants (Bone Level Tapered, Straumann) were placed in the edentulous maxilla at positions 12, 14, 16, 22, 24 and 26. In the second patient, 4 bone level implants (NobelActive CC, Nobel Biocare) were placed in the edentulous mandible at positions 32, 35, 42 and 45. A CAD-CAM procedure was initiated with the acquired IOS data to fabricate an interim IFCDP at the same day. Periapical radiographs were obtained of the implant-prosthetic connection of the definitive IFCDPs to verify the passive fit. Metrology software (Geomagic Qualify, 3D Systems - Matlab, Mathworks) was used to assess the implant analogs position in the 3D-printed casts used for fabricating the definitive IFCDPs. A quantitative occlusal relationship analysis was performed with IOS. RESULTS: Radiographic examination revealed no gaps at implant-prosthetic connection of the definitive IFCDPs. The 3D-printed casts showed an overall average distance deviation within the clinically acceptable range of errors of 150 µm. Quantitative occlusal relationship analysis with IOS showed well-distributed contacts. CONCLUSION: Within the limitations of this study, the following conclusions can be drawn: (1) A 3-unit toolset with ISBs, LPAs and OPAs allows to register the implant position and maxillomandibular relationship in one single visit; (2) the 2-stage clinical workflow with the CAPS system facilitates the IOS data acquisition for fabrication of an interim IFCDP at the same day; (3) a passive fit was demonstrated for the interim and the definitive IFCDPs. CLINICAL SIGNIFICANCE: The CAPS system can help clinicians to register the implant position and the maxillomandibular relationship in one single visit for the fabrication of an IFCDP.

Occlusal equilibration and muscle activity in fixed versus removable mandibular implant supported overdenture.

OBJECTIVES: Single denture rehabilitated patients have negative appraisals regarding oral function, mostly associated by stability and retention issues regarding mandibular prosthetics. Therefore, this study assessed patients' occlusal equilibration, muscle activity, and oral health-related quality of life (OHRQoL) receiving milled removable or fixed mandibular implant retained prostheses. MATERIALS AND METHODS: Twenty-two edentulous mandibular ridges patients were randomly distributed into two groups based on the definitive prosthesis received. Group I: Removable mandibular implant-supported overdenture, Group II: Implant retained fixed prosthesis. Occlusal equilibration was evaluated utilizing Occlusense, muscle activity via Electromyograph (EMG) at delivery, after one, and three months. The OHRQoL was evaluated by Oral Health Impact Profile questionnaire (OHIP-19) before delivery and after follow-ups. Data were collected, tabulated, and analyzed, utilizing independent t-test and One-way ANOVA followed Tukey`s post-hoc test. Significance level set at P ≤ 0.05. RESULTS: Groups I &II showed significant improvement in occlusal equilibration, muscle activity and OHRQoL. Group II demonstrated significantly higher improvement than group I in occlusal equilibration associated with muscle activity after 1 month, and in functional limitations domain in OHRQoL questionnaire after 3 months. CONCLUSION: Implant retained mandibular prosthesis showed improvement in occlusal equilibration, muscle activity, and OHRQoL regardless of prosthesis type employed. Fixed implant-supported prosthesis revealed better outcomes than removable mandibular implant-supported overdenture concerning occlusal equilibration, muscle activity, and OHRQoL regarding functional limitations. CLINICAL RELEVANCE: Implant retained mandibular prosthesis is one of best treatment options for single mandibular completely edentulous patients, as dental implants improved occlusal equilibration, muscle activity, and OHRQoL.

Clinical Measurements of Force Exerted on Anterior Teeth in Partial Edentulous Distal Extension.

PURPOSE: To determine the influence of partial edentulous distal extension and the use of removable partial dental prostheses in partially edentulous areas on the force exerted on the anterior teeth. MATERIALS AND METHODS: A total of 83 volunteer patients participated in this study. The occlusal force was measured using an occlusal force measuring sheet in the patient's mouth. The occlusal forces and ratios were compared using the Wilcoxon signed-rank test (P < .05). RESULTS: The force exerted on the anterior teeth increased significantly as the number of remaining teeth decreased in an edentulous distal extension. The force exerted on the anterior teeth decreased significantly with the use of a removable partial dental prosthesis. CONCLUSIONS: In a clinical setting, when the number of remaining teeth in a partial edentulous distal extension decreases, the burden on the anterior teeth increases. Our findings suggest that, for patients with partial edentulous distal extension, using a removable partial dental prosthesis is effective in preserving the residual anterior teeth by reducing excessive force.

Histological and radiological outcome after horizontal guided bone regeneration with bovine bone mineral alone or in combination with bone in edentulous atrophic maxilla: A randomized controlled trial.

OBJECTIVE: To assess the radiological and histological outcome after horizontal guided bone regeneration (GBR) with deproteinized bovine bone mineral (DBBM) alone or in combination with particulate autogenous bone (PAB). MATERIALS AND METHODS: Eighteen edentulous patients with an alveolar ridge of ≤4 mm were included in this split-mouth randomized controlled trial. Horizontal GBR with a graft composition of 100% DBBM (100:0) on one side and 90% DBBM and 10% PAB (90:10) on the other side were conducted in all patients. Cone beam computed tomography (CBCT) was obtained preoperatively, immediately postoperative, and after 10 months of healing. Width and volumetric changes in the alveolar process were measured on CBCT. Implants were placed after 10 months of graft healing where biopsies were obtained for histomorphometrical evaluation. RESULTS: The gained widths were 4.9 (±2.4) mm (100:0) and 4.5 (±2.0) mm (90:10) at 3 mm from the top of the crest, and 5.6 (±1.3) mm (100:0) and 4.6 (±2.1) mm (90:10) at 6 mm from the top of the crest. The mean volumetric reductions were 32.8% (±23.8) (100:0) and 38.2% (±23.2) (90:10). Histomorphometry revealed that mean percentages of bone were 50.8% (±10.7) (100:0) and 46.4% (±11.3) (90:10), DBBM were 31.6% (±12.6) (100:0) and 35.4% (±14.8) (90:10), and non-mineralized tissue were 17.6% (±11.7; 100:0) and 18.2% (±18.2) (90:10). No significant differences were evident between in any evaluated parameters. CONCLUSIONS: There were no additional effects of adding PAB to DBBM regarding bone formation, width changes, or volumetric changes after 10 months of graft healing.

Effect of calcium and Vitamin D supplementation on residual ridge resorption in edentulous patients: An open-label randomized study.

AIM: Complete dentures (CDs) are fabricated to rehabilitate the edentulous. Severe residual ridge resorption (RRR) compromises CD functionality, adversely affecting function, appearance, systemic health, and quality of life. SETTINGS AND DESIGN: The purpose of this study was to assess the benefit, if any, of calcium and Vitamin D supplementation on the rate of RRR. Retarding RRR would improve treatment prognosis and make CD fabrication less demanding. MATERIALS AND METHODS: This longitudinal, parallel, open-label randomized study was conducted in the Department of Prosthodontics of the institute. One hundred and fifty edentulous subjects underwent bone mineral density (BMD) assessment followed by CD fabrication to measure RR height and width with computerized tomographic (CT) scans. Subjects were randomized to oral supplementation group - S, given combined Vitamin D and calcium daily, and nonsupplementation group - NS. Subjects from both the groups were followed up with repeat BMD test and CT scan after 12 months. Mean BMD, RR height and width, and RRR values were collected, analyzed, and compared for the two groups using STATA 17. STATISTICAL ANALYSIS USED AND RESULTS: Baseline mean T-score, RR height, and RR width were - 1.84, 22.30 mm, and 4.25 mm, respectively, for the sample. In both Groups S and NS, a statistically significant decrease in mandibular RR height (P = 0.000 for both) and width (P = 0.027 and 0.003, respectively) was observed at 1-year follow-up. There was a statistically insignificant difference between Groups S and NS for mean BMD, T-score, RR height and width, and RRR at both baseline and 12-month follow-up. One-year RRR rate for Group S (1.30 mm) was insignificantly lesser than for group NS (1.33 mm). CONCLUSION: Short-term oral calcium and Vitamin D supplementation was ineffective in reducing RRR and improving BMD.

Effect of zirconia surface conditioning before glazing on the wear of opposing enamel: an in vitro study.

OBJECTIVES: This in vitro study aimed to evaluate the wear of natural teeth opposing 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) with different surface conditions. MATERIALS AND METHODS: Sixty 3Y-TZP specimens were randomly assigned to six groups (n = 10), differing in surface condition. In three groups, the samples underwent glazing-with the glaze applied to roughened (i.e., 106-µm-grit diamond-finished), as-sintered, and polished zirconia. The three remaining groups consisted of unglazed specimens: solely polished samples and diamond-finished samples (106-µm-grit and 46-µm-grit) without further conditioning. Two-body wear was evaluated at extracted, non-carious molars (n = 60), which served as antagonists in chewing simulation (10,000 masticatory cycles, 49N load). As a control, natural teeth with intact enamel surfaces were tested against natural molars (n = 10). All samples were 3D-scanned before and after the chewing simulation (7 Series, Straumann). Volume loss was calculated (Inspect Software, GOM), and statistically analyzed (SPSS Statistics 24, IBM). RESULTS: Volume loss of the natural antagonists decreased in the following order: 106-µm-grit diamond-finished zirconia (4.6 ± 2.5 mm3), glazed 106-µm-grit diamond-finished zirconia (3.8 ± 1.1 mm3), glazed as-sintered zirconia (3.5 ± 0.9 mm3), 46-µm-grit diamond-finished zirconia (1.7 ± 0.6 mm3), control (1.6 ± 0.7 mm3), glazed polished zirconia (1.4 ± 0.5 mm3), and solely polishing (0.4 ± 0.2 mm3). Even when polishing the surfaces before glazing, volume loss was not mitigated to the same extent as after polishing alone. CONCLUSIONS: The zirconia surface condition beneath the glazing influences antagonist wear. Although polishing before glazing resulted in acceptable levels of antagonist wear, this approach did not yield as favorable results as polishing alone. CLINICAL RELEVANCE: For operators favoring glazing, pre-polishing the zirconia surface could be advantageous to reduce wear.

In vitro comparative study between complete arch conventional implant impressions and digital implant scans with scannable pick-up impression copings.

STATEMENT OF PROBLEM: Intraoral digital scan techniques have been widely used and sufficient evidence supports this technique in partially edentulous patients. However, the evidence supporting the use of intraoral scanners (IOSs) for edentulous patients is limited. PURPOSE: The purpose of this in vitro study was to measure and compare the accuracy of complete arch conventional pick-up implant impressions with open and closed trays, complete arch digital implant scans with IOSs, and 3-dimensional (3D) printed casts from complete arch digital implant scans. MATERIAL AND METHODS: Six implants were placed in a mandibular model. Scannable pick-up impression copings were inserted in the implants, scanned with a reference scanner, and exported in standard tessellation language (STL) format (Group Control). Splinted open-tray pick-up impressions (Group OT, n=5) and closed-tray pick-up impressions (Group CT, n=5) were made, and stone casts were fabricated. Digital scans (Group DS, n=5) were made with an IOS, and the STL files were exported to fabricate 3D printed casts (Group STL, n=5). Scannable pick-up impression copings were inserted in the dental implant analogs in Groups OT, CT, and STL and scanned with the reference scanner. Using a 3D inspection software program, the recording techniques were compared with the control. Root mean square (RMS) values were calculated from the control, and superimposed digitized casts from different recording techniques. Analysis of variance was used to determine differences in RMS values, and theTukey post hoc test was used to determine difference between different groups. RESULTS: Group CT had the lowest mean dimensional difference when superimposed with Group Control, followed by Groups DS, OT, and STL. Significant differences were found in RMS values between Control and digitized casts fabricated with different techniques (P<.05). The post hoc Tukey test revealed that Group DS (P<.05) was significantly different from the other groups, while no significant difference was found among Groups CT, OT, and STL (P>.05). CONCLUSIONS: Based on the findings of the present study, 3D printed casts from digital scans have the same accuracy as stone casts from conventional impressions in complete arch implant cases. Intraoral scans had the highest accuracy. Complete arch pick-up impression techniques using dual-functioning scannable pick-up impression copings are as accurate as splinted complete arch pick-up impressions.

Oral frailty among dentate and edentate older adults in long-term care.

BACKGROUND: The objectives of this study were to compare oral frailty (OFr) among edentate and dentate older adults living in long-term care facilities (LTCF) and to clarify how edentulism and oral disease burden (ODB) of dentate older adults are associated with OFr. METHODS: The population of this study comprised 94 edentate and 209 dentate residents in LTCF in Helsinki, Finland, who had previously participated in a nutritional study. The participants underwent a clinical oral examination. The dentate residents were further divided into three ODB groups based on asymptotic dental score. The edentate and different ODB groups were compared with each other regarding demographics and oral and medical findings. OFr was defined as ≥ 2 of following: having a diet of soft/pureed food, residue of food in the oral cavity, inability to keep the mouth open during examination, unclearness of speech, dry mouth. The association between OFr and edentulousness and various levels of ODB was analyzed by a multivariate logistic model. RESULTS: Participants with low ODB had significantly less OFr than their edentate peers (p = 0.009). Furthermore, the edentate and dentate with high ODB had similar odds for OFr. CONCLUSIONS: Edentulousness and high ODB are equally harmful conditions and may predispose to OFr. This study suggests that maintaining healthy natural teeth and good oral health (low ODB) may protect against OFr. TRIAL REGISTRATION: The Ethics Committee of the Hospital District of Helsinki and Uusimaa approved the protocols for the nutritional status and oral healthcare studies and the merging of the data, including patient medical records (Register number HUS/968/2017).