Acrylic Denture Research Articles

Effect of different surface treatments on tensile bond strength of acrylic denture teeth to CAD/CAM denture base

Purpose This study evaluated the effect of different surface treatments on tensile bond strength of acrylic denture teeth to prepolymerized computer-aided design/computer-aided manufacturing (CAD/CAM) denture base resin (PMMA) under two different storage conditions. Patients and methods 160 test specimens were used in this study, each specimen has two parts: the first part: is an acrylic cross-linked maxillary central incisor denture tooth embedded in acrylic resin blocks, and the second part: is cone shape (5 mm × 5 mm × 3 mm) specimens prepared from prepolymerized PMMA discs by computer numerically controlled (CNC) milling machine under water cooling. Test specimens were divided into four main groups 40 each according to tooth surface treatment. Group I: no sandblasting. Group II: sandblasted using 50 μm aluminum oxide. Group III: sandblasted using 150 μm Al2O3. Group IV: sandblasted using 200 μm Al2O3. Each group was divided into 2 subgroups (A, B) 20 each, subgroup A used resin cement bond first part with the second part. Subgroup B used a bonding agent to bond the first part with the second part. Each subgroup was divided into 10 specimens that were stored in 50 hours of distilled water storage and 10 specimens were thermocycling. All specimens were then subjected to a tensile load using testing machine at a crosshead speed of 1 mm/min until debonding. The resulting debonding forces were recorded and statistically analyzed. For all specimens, the interface was inspected. The interface failures were classified into adhesive and cohesive failures. The data were analyzed using a three-way Analysis of Variance (ANOVA), followed by Tukey’s test. Results The highest mean value tensile bond strength was recorded for GIV (6.5 ± 1.46). Sandblasting was improving the tensile bond strength value of all the specimens. Bonding agents without and with surface treatment significantly improved the tensile bond strength of all specimens. The thermocycling significantly decreased the tensile bond strength of all specimens. Conclusion Sandblasting of denture teeth followed by bonding agent improved the tensile bond strength to CAD/CAM denture base. Thermocycling decreased the tensile bond strength of acrylic denture teeth to CAD/CAM denture base.

Evaluation of the Effects of Different Polishing Protocols on the Surface Characterizations of 3D-Printed Acrylic Denture Base Resins: An In Vitro Study.

Chairside polishing kits are an alternative to laboratory polishing techniques. The effects of using a chairside polishing kit on a three-dimensional (3D)-printed acrylic denture base (ADB) have not been reported previously. Thus, this study aimed to evaluate the effects of different chairside polishing techniques on the surface characterizations of ABD, including surface roughness average (Ra), average maximum profile height (Rz), and scanning electron microscopy (SEM) representations. One hundred and twenty disc-shaped specimens were fabricated from one conventional heat-polymerized (HP) ADB resin and two 3D-printed (Asiga (AS) and NextDent (ND)) ADB resins (n = 40 per material). Each group was further divided based on the polishing protocol (n = 10) as follows: conventional polishing protocol (C), microdont chairside polishing kit (M), shofu chairside polishing kit (S), and an unpolished group (U). The Ra and Rz values were measured using an optical profilometer. Two-way ANOVA and post hoc tests were used for data analysis (α = 0.05) at significant levels. In unpolished groups, there was a statistically significant difference between HP-U vs. AS-U and ND-U groups (p < 0.0001). For Ra, the lowest values were observed in HP-C, AS-S, and ND-C. While the highest values were shown in all unpolished groups. Within the material, there were statistically significant differences between the three polishing protocols (C, M, and S) vs. unpolished (p < 0.0001), while there was no significant between C, M, and S groups (p = 0.05). The Rz values had the same pattern as the Ra values. The two chairside polishing kits were comparable to conventional polishing techniques, and they can be recommended for clinical application.

Effect of Chlorhexidine and Castor Oil on Surface Roughness of Heat-Cured Acrylic Resin Denture Base

Background: Heat-cured acrylic resin is the acrylic resin most often used to make denture bases. In its use as a denture base, heat-cured acrylic resin requires a disinfectant to clean it from contamination by microorganisms. Still, it does not affect other properties of the heat-cured acrylic resin. Objective: This study aimed to determine the effect of heat-cured acrylic resin denture base disinfection with chlorhexidine and castor oil on surface roughness. Materials and Methods: This research is laboratory experimental with 30 bar-shaped (50x20x3mm) heat-cured acrylic resin-denture base specimens samples were divided into two groups, with chlorhexidine 0.2% simulated 3, 4, and 5 years and with castor oil 10% affected 3, 4, and 5 years. The surface roughness was tested using the Roughness tester TR200. Data were analyzed using univariate statistics and an independent t-test (α = 0.05). Results: The research showed no significant effect in the disinfection of heat-cured acrylic resin denture base with 0.2% chlorhexidine and 10% castor oil on surface roughness of 3, 4, and 5 years (p 0.05). Castor oil of 10% can be used as a disinfectant for the heat-cured acrylic resin denture base because it does not affect the surface roughness. Conclusion: Chlorhexidine 0.2% and castor oil 10% had the same effect on changes in surface roughness on heat polymerized acrylic resin denture base.

PROSTHETIC TREATMENT OF PATIENT WITH MANDIBLE RESECTION

Background: Literature findings indicate an increase in mandible resection cases. Retention and stability of dentures are the main issues in the prosthetic treatment of these defects. Aim: The aim of the presented clinical case is to explore the possibility of prosthetic treatment of a patient with mandible resection of the frontal area. Materials and methods: The clinical case monitors the prosthetic treatment of a 38-year-old patient with mandible cancer and resection in the frontal zone. The treatment plan was based on taking preliminary alginate impressions and developing gypsum models. It is planned to develop a partial acrylic denture sealed with silicone material. Additional preparation of the gypsum master model in the resection area took place in order to achieve the equal thickness of the special silicone material. The base of the alveolar bone was restored with hard plaster. In addition, the occlusal rim was fabricated with the purpose of establishing the centric relation and occlusal relationship. The denture was fabricated by acrylic resin with a low quantity of residual monomer and adjusted after adding silicone material over the resected part with functional tests to complete the design of the defect area. Results: The accessed treatment results indicate good retention and stability of the denture. The application of silicone material provided a non-traumatic transition of the masticatory pressure without decubital ulcers in the resected zone. Conclusion: The application of appropriate prosthetic treatment methods in patients with mandible resection leads to the successful restoration of feeding and speaking functions.

EFFECT OF DIFFERENT DRINKS ON STAINABILITY OF ACRYLIC DENTURE TEETH

Acrylic denture teeth may experience colour change after some time in service. The aim of this study was to evaluate the discolouration of the acrylic denture teeth when immersed in tea and cola solutions. These solutions were chosen as they are the daily drink by most Malaysians despite of the age based on surveys in Malaysia. 45 first maxillary anterior acrylic denture teeth were divided into three groups (n=15): control (distilled water), tea and cola solutions. The colour changes were recorded after Day 1, Day 7, Day 15 and Day 30 using Coral dental shade guide and visible spectrometer. The visible spectrometry analysis showed that there is a relatively distinctive feature between reflectance from samples immersed in tea and cola. There is strong indication of colour changes for the samples immersed in tea compared to cola, particularly for wavelength between 400-500 nm after 30 days. The result shows that acrylic teeth became slightly darker when immersed in the tea solution for 15 days and 30 days. Average discolouration of the acrylic teeth on day 15 was 1.1333 (SD 0.3519) and day 30 was 1.4467 (SD 0.5164). On the contrary, teeth immersed in cola did change colour but became slightly brighter. The colour change is insignificant, indicating the stable properties of acrylic denture teeth colour and they were not influenced by extrinsic factors. The discolouration of acrylic resin denture teeth was time dependent and increased proportionally with the immersion period.

Retention of titanium copings to implant-supported fixed dental prostheses.

The aim of this in vitro study was to assess the effects of using different cements and titanium copings designs on the retention of implant-supported fixed dental prostheses (IFDPs) using a pull-out test. Fifty zirconia (ZirCAD; Ivoclar Vivadent) and 20 prepolymerized denture acrylic resin (AvaDent) rectangular (36mm × 12mm × 8mm) specimens were milled to mimic the lower left segmental portion of the All-on-Four IFDPs. Cylindrical titanium copings (Variobase; Straumann) (V) were used in 2 prepolymerized denture acrylic resin groups (n = 10) while conical titanium copings (Straumann) (C) were used as a control group for zirconia with 4 groups using cylindrical titanium copings. Before cementation, the outer surfaces of all titanium copings and the intaglio bonding surface of prosthetic specimens were airborne-particle abraded. All specimens were cemented following the manufacturer's recommendations and instructions according to the experimental design. After artificial aging (5000 cycles of 5°C 55°C, dwelling time 20s; 150 N, 1.5Hz in a 37°C water bath), all specimens were subjected to retention force testing using a pull-out test using a universal testing machine and a custom fixture with a crosshead speed 5mm/min. Modes of failure were classified as Type 1, 2, or 3. Retention force values were analyzed by the t-test for the prepolymerized denture acrylic resin specimen groups, and 1-way ANOVA and the Tukey test for the zirconia groups at α = 0.05. Mean and standard deviation retention force values varied from 101.1±67.1 to 509.0±65.2 N for the prepolymerized denture acrylic resin specimen groups. The zirconia groups ranged from 572.8±274.7 to 1416.1 ±258.0 N. There is no statistically significant difference in retention force values between V and C specimens cementing to zirconia with Panavia SA cement (Kuraray Noritake) (p = 0.587). The retention forces and failure modes were influenced by the cement used (p < 0.05). Modes of failure were predominantly Type 2 (mixed failure) and Type 1 (adhesive fracture from prosthetic materials) except for the quick-set resin group (Type 3, adhesive failure from coping). When bonding IFDPs onto titanium copings, quick-set resin provided significantly higher retention force for prepolymerized denture acrylic resin prostheses. Conical and cylindrical titanium copings performed similarly when cemented to zirconia with Panavia SA cement under the same protocol. The stability of the bonded interface and retention forces between zirconia prostheses and titanium copings varied from the cement used.

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

Statement of problemLimited data are available regarding the most suitable separating medium for fabricating dental acrylic resin prostheses or appliances on 3-dimensional (3D)-printed resin casts. PurposeThe 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 methodsA 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). ResultsSignificant 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). ConclusionsThe 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.

EFFECT OF CATHA EDULIS (KHAT) EXTRACT ON COLOR STABILITY OF ACRYLIC RESIN DENTURE TEETH: AN IN-VITRO STUDY

Background and aim: Long-term denture tooth color stability for patients is an important criterion in choosing the types of dental materials to use as one of the main concerns in treatment. Discoloration of denture teeth may result in patient dissatisfaction and an additional expense for their replacement. In Yemen, khat (Catha Edulis) chewing habit may affect the color of acrylic denture teeth. The aim of this study was to assess the effect of khat extract on color stability of reinforced acrylic resin denture teeth. Materials and Methods: Experimental design carried to 3 brands of reinforced acrylic resin teeth from three manufacturers, Vitapan, FX-Anterior and Shanghai-SND were evaluated 40 specimens (maxillary central incisors) of each brand were selected systematically and grouped into A, B and C respectively. All samples were stored in distilled water (DW) at 37 °C for 24 hours after which baseline colorimetric measurements were recorded by colorimeter. All the specimens were immersed for 24 hours daily and kept in an incubator at 37°C for 30 days. The KH was changed every 24 hours. Colorimeter was used for color change testing of each specimen after 10, 20 and 30 days on CIE L* a* b*. Then the collected data was analyzed using SPSS version 23. Results: The results of this study shows that there was a significant effect of KH on acrylic teeth (p&lt;0.001). Also, a significant interaction between the three brands acrylic teeth and KH was found (p&lt;0.05). The effect of time on acrylic teeth color stability was statistically significant (p&lt;0.05). The brands teeth specimens at 10, 20 and 30 days in KH revealed more significantly color change than DW (p&lt;0.05). Conclusions: The khat homogenate (KH) causes discoloration on the 3 brands of reinforced acrylic teeth and the discoloration increases with the passage of time. The change of discoloration is acceptable clinically except in SND teeth. Vitapin teeth has more color stable compared to FX teeth and SND teeth. Peer Review History: Received: 12 February 2023; Revised: 13 March; Accepted: 25 April 2023, Available online: 15 May 2023 Academic Editor: Prof. Dr. Gorkem Dulger, Duzce University, Turkey, gorkemdulger@yandex.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Khaled A AL-Haddad,Orthodontics, Pedodontics and Prevention Department Faculty of Dentistry, Sana'a University, Yemen, ya_haddadi@yahoo.com Dr. Masoomeh S Ghahfarokhi, University of Benin, Nigeria, mshamsgh@yahoo.com

Vertical Occlusal Dimension Changes of Complete Dentures between Autoclave and Traditional Processing Techniques

The aim of the present in vitro study was to investigate the effect of using an autoclave with three different programs and the traditional water bath method (short cycle) on the changes in the vertical occlusal dimension of the complete acrylic dentures. Forty complete acrylic dentures were divided into four groups: G1, dentures were polymerized by water bath method (short cycle for 90 min at 74 °C and then 30 min at 100 °C); G2, dentures were polymerized with an autoclave (134 °C/2.1 bar/10 min); G3, dentures were polymerized with an autoclave (121 °C/1.1 bar/20 min); and G4, dentures were polymerized with an autoclave (121 °C/1.1 bar/5 min). The vertical occlusal dimension of the dentures was measured before and after the polymerization process. The difference between the initial and final measurements expressed the change in the vertical occlusal dimension. Data were statistically analyzed by t-test and one-way ANOVA test. Statistically significant lower vertical dimension changes were detected in G1 (0.703 ± 0.078 mm) compared to the other groups (p &lt; 0.05), whilst statistically greater changes were detected in G4 (1.263 ± 0.063 mm) compared to the other groups. No statistically significant differences were found between G2 (0.844 ± 0.061 mm) and G3 (0.88 ± 0.059 mm) (p &gt; 0.05). Within the limitations of the present in vitro study, it can be concluded that all polymerization methods increase the vertical occlusal dimension of complete acrylic dentures. The increase in the vertical occlusal dimension in Groups 1, 2 and 3 was less than 1 mm which is clinically acceptable and can be overcome by selective abrasion. Therefore, the traditional curing technique using a water bath and the autoclave methods using two settings (134 °C/2.1 bar/10 min or 121 °C/1.1 bar/20 min) could be used for the complete acrylic denture with acceptable augmentation in the vertical occlusal dimension. In contrast, the method used in G4 increases the vertical occlusal dimension by more than 1 mm, which is not clinically acceptable.

The Visual and Instrumental Analyses of Different Single-Shade Resin Composites

The purpose of this study was to evaluate the color adaptation of single-shade resin composites applied to different tooth shades. A total of 108 class III preparations (n=6) were performed on the acrylic denture maxillary incisors (2mm depth and 2mm height). 5 single-shade resin composites (Vittra APS Unique, Omnichroma, ZenChroma, Clearfil Majesty ES-2 Universal, Charisma Topaz One) and 1 multishade resin composite (Estelite Asteria) were placed in the cavities and polished. I performed visual and instrumental color analyses. The CIEDE2000 formula was used to assess the shade differences (∆E) between teeth and restorations. The obtained ∆E values were recorded and statistically analyzed. For the instrumental analysis, ZenChroma in A1 shade groups showed statistically significant higher differences (p&lt;0.05). Among all tested materials, A3 shade groups showed lower ∆E values (p&lt;0.05). For the visual analysis, there were no significant differences between materials and scores in A1 and A3 shade groups (p&gt;0.05). There were statistically significant differences between the materials and the scores in A2 shade groups (p&lt;0.05). As a result of this study, it was concluded that, making esthetic restorations with single-shade resin composites promises proper color adaptation, but their properties still need improvement. Single-shade resin composites can reduce chair-time and technical sensitivity with good color matching.

Fiber-reinforced composite full-arch prosthetic reconstructions supported by three standard, short or extra-short implants: a two-center retrospective study.

To evaluate the survival of implants and prostheses, and marginal bone level of fiber-reinforced composite implant supported fixed complete prostheses supported by 3 implants. Patients with fiber-reinforced composite fixed prostheses supported by 3 standard-length, short or extra-short implants were included in this retrospective cohort study. Kaplan-Meier survival was computed for implants and prostheses. Univariate and multivariate Cox proportional hazard regressions, clustered by patient, were used to analyze bone level differences as a function of different study covariates. Linear regressions were used to investigate the relationship between distal extension lengths and bone levels. Forty-five patients with 138 implants were followed for up to 10years after prosthesis insertion (mean 52.8; SD 20.5months). Kaplan-Meier survival analysis showed overall survival rates of 96.5% for implants and of 97.8% for prostheses. The 10-year success rate for prostheses was 90.8%. Extra-short implants survived at similar rates to short and standard implants. Marginal bone levels surrounding implants remained stable over time, even showing slight bone gain on average (mean + 0.1mm/year; SD ± 0.5mm/year) Acrylic denture teeth, overdentures on the opposing arch, and implant placement in the posterior maxilla were correlated with bone gain. Screw retention, opposed to telescopic retention, was correlated with bone loss. Longer distal extensions were correlated with bone gain on the implants closest to the distal extensions. Fiber-reinforced composite fixed prostheses supported by only 3 implants, most of which were extra-short, presented high survival rates with stable bone levels. An encouraging prognosis can be expected for restoration of atrophic maxillary and mandibular arches, when restored with fixed fiber-reinforced composite frameworks with long distal extensions and supported on only 3 short implants.

CAST PARTIAL DENTURE FOR REHABILITATION OF PARTIAL EDENTULISM WITH DISTAL EXTENSION: A CASE REPORT

Loss of teeth has a negative impact on patients oral health and mental well being.While treating a patient with partial edentulism the restorative dentist should not ignore the patients concern and thereby the planned treatment modality should best suit the patient.In this clinical report a patient with partial edentulism(Keneddy class II mod 2) was rehabilitated with cast partial denture over acrylic partial denture and other fixed dental treatment as it was considered to be the most viable treatment option.

Intelligent Materials for Labeling Dentures in Forensic Dental Identification—A Pilot Study

(1) Background: the present study continues previous research on new marking techniques by using intelligent materials, NFC-tags (Near Field Communication tags) and Aerogel. They prevent the loss of information over time for cadavers of unknown identities in various stages of destruction or unknown living victims, as well as missing persons who have lost or are concealing their identity. (2) Methods: this study consisted of a technological and an experimental stage. In the technological stage, two different sizes were used: round (Ø 1 cm, 0.1 mm thickness, 0.1 g weight) and square (5/5/0.1 mm), both with a 140 byte memory and high-temperature resistance (at max. 200 °C), (by the classical producing technology). After loading the identification information on the NFC-tags, they were embedded (either alone or protected by Aerogel) in the sample dentures using a new “sandwich technique” method, before the polymerization process. In the experimental stage, the sample dentures with the new materials were exposed to various damaging environments such as liquid media (sea water, fresh water, alcohol 40%, and HCl 0.2%) in order to test the time resistance of the identification elements. The samples were monitored and tested over four years. (3) Results: the information stored on the NFC tags was retrieved unaltered at the end of the monitoring period, regardless of the damage caused by the liquid media to the sample denture material and will provide an innovative solution as compared to other labeling methods. (4) Conclusion: the use of intelligent materials for labeling acrylic dentures provides additional reliability by preserving the identification information over time.

Effect of acrylic denture immersion in mangosteen rind extract on shear bond strength of artificial teeth with denture base

Effect of acrylic denture immersion in mangosteen rind extract on shear bond strength of artificial teeth with denture base

Evaluation of Two Denture Base Material on the Supporting Structures of Mandibular Tooth Supported Over Denture

Purpose: To compare the effect of thermoplastic resin and heat cured acrylic resindenture base materials on pocket depth and bone height around two mandibular caninessupporting mandibular tooth supported over denture. Subject and Methods: Tenpatients having completely edentulous maxillary ridge and bilateral canine in the lowerarch were selected. Root canal treatment and preparation were performed to obtainnon coping abutment with amalgam plugs that covered with over denture. Maxillarycomplete dentures were constructed for all patients. Patients were divided into two equalgroups. Group I: received thermoplastic mandibular over denture. Group II: receivedconventional heat cure acrylic resin mandibular over denture. Clinical and radiographic evaluation were performed at denture insertion , after 6month and after 9monthfor both mandibular over denture. Results: Statistical analysis of bone height showedthat group I (thermoplastic denture) has less bone resorption than group II (acrylicdenture) which was statically significant. Statistical analysis of change in pocket depthshowed that group I (thermoplastic denture) has less change in the pocket depth thangroup II (acrylic denture) which was not statistically significant. Conclusion: Withinthe limitation of this study thermoplastic over denture preserved pocket depth and boneheight more than conventional heat cured acrylic resin.

Evaluation of Two Denture Base Material on the Supporting Structures of Mandibular Tooth Supported Over Denture

Purpose: To compare the effect of thermoplastic resin and heat cured acrylic resindenture base materials on pocket depth and bone height around two mandibular caninessupporting mandibular tooth supported over denture. Subject and Methods: Tenpatients having completely edentulous maxillary ridge and bilateral canine in the lowerarch were selected. Root canal treatment and preparation were performed to obtainnon coping abutment with amalgam plugs that covered with over denture. Maxillarycomplete dentures were constructed for all patients. Patients were divided into two equalgroups. Group I: received thermoplastic mandibular over denture. Group II: receivedconventional heat cure acrylic resin mandibular over denture. Clinical and radiographic evaluation were performed at denture insertion , after 6month and after 9monthfor both mandibular over denture. Results: Statistical analysis of bone height showedthat group I (thermoplastic denture) has less bone resorption than group II (acrylicdenture) which was statically significant. Statistical analysis of change in pocket depthshowed that group I (thermoplastic denture) has less change in the pocket depth thangroup II (acrylic denture) which was not statistically significant. Conclusion: Withinthe limitation of this study thermoplastic over denture preserved pocket depth and boneheight more than conventional heat cured acrylic resin.

Cytotoxicity and Microbiological Assessment of Maxillary Acrylic Resin Complete Dentures Reinforced by Gold Plated Cr-Co Palatal Plate (A Randomized Controlled Clinical Trial with Laboratory Assessment)

Cytotoxicity and Microbiological Assessment of Maxillary Acrylic Resin Complete Dentures Reinforced by Gold Plated Cr-Co Palatal Plate (A Randomized Controlled Clinical Trial with Laboratory Assessment)

Protective periodontitis: the possibility of prevention

Relevance. The isolation of prosthetic periodontitis among inflammatory periodontal pathology has significantly supplemented the generally accepted notions of dentists concerning the etiology and progression of dental prosthetics complications. Improving the methods of preventing inflammatory periodontal lesions caused by the presence of denture structures in the oral cavity is very relevant nowadays, especially in persons using removable dental prostheses. This applies to older age groups, which for financial reasons are more accessible removable acrylic dentures, which they have the opportunity to get at the expense of the budget of the region.Aim. This applies to those in the older age groups who, for financial reasons, have more access to removable acrylic dentures because of the possibility of obtaining dentures at the expense of the regional budget. Therefore, the aim of the study was to assess the possibility of using a new domestic denture fixation cream for the prevention of prosthetic periodontitis in patients using removable dentures.Materials and methods. 63 (18 male and 45 female) elderly patients (61-74 years old) with partial tooth loss on both jaws were examined. Partial removable acrylic dentures were made for patients 1st group (n = 30) and 2nd group (n = 33). The patients of the second group constantly used the domestic ASEPTA РARODONTAL denture fixation cream with herbal extract for 9 months of the study. Assessment of the impact of dentures on the oral tissues and periodontium was carried out on the basis of clinical examination and by studying the antimicrobial potential of saliva.Results. The use of partial removable acrylic dentures has been found to contribute to the occurrence of prosthetic periodontitis, which is associated with the technology used in their manufacture. It is possible to reduce the incidence of prosthetic periodontitis not only by timely correction of prosthesis but also by using adhesive means for fixation of prosthesis, the application of which permitted to reduce the occurrence of prosthetic periodontitis by 47,58% and to reduce the occurrence of inflammatory changes of gingiva in the restored teeth area by 16,06%. The research of the antimicrobial potential of saliva in persons who constantly used ASEPTA РARODONTAL denture fixation cream with herbal extract showed that the immune balance achieved before dental prosthetics can be maintained in the oral cavity.Conclusion. The results of the clinical and laboratory study allow us to recommend more widely the use of adhesive means for fixation of removable dentures, including the ASEPTA PARODONTAL cream with herbal extracts.

Using a Three-Dimensional Superimposition Technique, Studying the Effects of Different Cooling Procedures on the Adaptability of Rapidly Heat-Cured Acrylic Denture Bases

Using a Three-Dimensional Superimposition Technique, Studying the Effects of Different Cooling Procedures on the Adaptability of Rapidly Heat-Cured Acrylic Denture Bases

Does a sloped neck implant design facilitate All-on-4 surgeries? A three-dimensional finite element analysis

Aim: In the treatment of edentulous resorbed mandibles using All-on-4 concept, the distal part of posteriorly tilted implants with a conventional flat neck design is usually embedded in the bone, which may lead to improper installation or positioning of angled multiunit abutments. Bone trimming from the distal area, where the implant neck is embedded in the bone, is typically necessary to avoid this complication. This study aimed to evaluate the biomechanical behavior of a sloped marginal neck configuration of implant posteriorly tilted at 30° in edentulous mandibles using a three-dimensional finite element analysis (FEA). Methodology: The sloped neck implants were posteriorly tilted at 30° without any further operation in the edentulous mandibular model designed using the FEA. The tilted conventional flat neck implants were placed at the same length, diameter, and angle, and 2 mm2 of bone was trimmed from the distal area. Similar multiunit abutments, two conventional flat neck implants axially placed on the anterior side, titanium frameworks, and acrylic resin prosthetic dentures were created for both models. The biomechanical behaviors of the models were evaluated by applying a foodstuff force of 50 N to the incisors, 100 N to the premolars, and 150 N to the molar cantilever. Results: The von Mises stress value of the sloped neck implants (158.489 MPa) was lower than that of the conventional flat neck implants (177.208 MPa). Both the maximum and minimum principal stress values ​​in the surrounding cortical and cancellous bones were within the acceptable physiological limits. Conclusion: Sloped neck implants can be placed easily and are less invasive than conventional flat neck implants; thus, they can be a treatment alternative that can facilitate the All-on-4 concept. How to cite this article: Toprak ME. Does a sloped neck implant design facilitate All-on-4 surgeries? A three-dimensional finite element analysis. J Med Dent Invest 2023;4:e230310. https://doi.org/10.5577/jomdi.e230310 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.