Telescopic Crowns Research Articles

Mandibular Implant-Supported Overdentures Using Telescopic Crowns and Immediate Loading Protocol: A 2-Year Prospective Follow-up Study.

Implant-supported overdentures have been an effective treatment method for edentulous mandibles. However, the loading time after implant placement is still controversial. The purpose of this study was to evaluate the outcome of implant-supported overdentures using telescopic crowns for the treatment of edentulous patients with immediate loading protocol. This study was conducted on 22 edentulous mandibular patients visiting the Department of High Technique, National Hospital of Odonto - Stomatology, Ho Chi Minh City, Vietnam for prosthodontic rehabilitation. Each patient received four interforaminal implants. Immediate loading protocol was applied, and Ankylos Syncone copings systems was used to connect the prosthesis and the implants. The survival rate of implants and prostheses, as the primary outcome, were evaluated at 6 months, 01 year, and 02 years post-surgery. Peri-implant tissue condition, peri-implant bone loss, and patient satisfaction were the secondary outcomes. The implant survival rate was 98.9% with 01 failed implant. The peri-implant bone loss changes after 6 months, 01 year, and 02 years were 0.07 ± 0.22 mm, 0.12 ± 0.3 mm, and 0.15 ± 0.2 mm, respectively. No gingival hyperplasia was recorded. The prosthesis survival rate was 86.4% with 1 fractured overdenture, 1 overdenture relining and 1 abutment fracture. Mandibular rehabilitation using implant-supported overdenture with telescopic crowns and immediate loading protocol showed high survival rates of both implant and prosthesis in 2-year follow-up.

Surface topography changes and wear resistance of different non-metallic telescopic crown attachment materials in implant retained overdenture (prospective comparative in vitro study)

BackgroundThe purpose of this study was to evaluate the effect of using different types of metallic and non-metallic telescopic crown attachment materials on wear resistance and surface tomography changes in implant-retained mandibular overdentures.Materials and methodsCompletely edentulous mandibular epoxy models were fabricated, in which two implants were placed in the canine region and retained to the implants with three different material combinations used for the construction of telescopic attachments. Thirty-three identical mandibular overdentures were fabricated using the conventional standardized technique. The study groups were divided into three categories according to the material used for the construction of the secondary copings. The primary copings in all the study groups were constructed of PEEK, while the secondary coping in group I was PEEK, group II was ZrO2 and CoCr for group III. Primary copings were cemented on a ready-made abutment. Secondary copings were placed over the primary copings in the desired path of insertion, then picked up into the intaglio surface of the overdentures. A cyclic loading machine was used to apply repeated insertion-removal cycles simulating nearly 10 years of clinical use. Stereomicroscope with a built-in camera was used to monitor the reduction in width of the primary copings to evaluate the wear resistance of each material combination.ResultsThere was highly statistically significant difference between the study groups after the application of 1.000, 5.000 and 10.000 cycles. The highest level of wear resistance was recorded for the PEEK/PEEK combination, whereas PEEK/ZrO2 and PEEK/CoCr showed no significant differences.ConclusionsImplant retained overdenture with PEEK-PEEK telescopic crown attachment is associated with the highest wear resistance among all the study groups. PEEK-PEEK combination may be the treatment of choice for fabrication of telescopic attachment in implant retained overdenture as it provides better resistance to wear. It offers the advantages for geriatric patients as it decreases the possibility for repeated repair and replacement of attachment, increase long-term patient satisfaction and shelf life of prosthesis.

Post and Core Treatment to Refit Telescopic Crown-Retained Dentures after Abutment Tooth Fracture: An Evaluation of Therapy by Retrospective Survival Analysis.

Telescopic crown-retained dentures (TCDs) are one of the most common types of prosthetic restorations for partially edentulous patients; however, post and core (PC) treatment shows the worst survival probability if the tooth is used as an abutment for the TCD. Due to extra axial forces, abutment tooth fracture is a common cause of failure for TCDs; thus, PC treatment is often needed to refit the existing telescopic crown (TC). However, there are no clinical survival data on whether the PC treatment was used to refit the TC after abutment tooth fracture (PC2) or the PC was already fitted at the time of TCD treatment (PC1). A total of 246 patients with 399 PC treatments were retrospectively evaluated for follow-ups up to 17.33 years. The files were analysed for PC1 and PC2. Furthermore, the influence of the jaw, type of tooth, luting material, PC material, bone attachment, therapist and cause of failure was recorded. For statistical analysis, Kaplan-Meier and Cox regression analyses were conducted. PC2 showed highly significant lower survival probabilities than PC1 (p < 0.001). Moreover, the bone attachment and the age of the patient at the time of fitting the PC crown had an influence on the survival (p < 0.001). Therefore, PC2 should be carefully discussed with the patient and PC1 should be favoured in endodontically treated abutment teeth for TCDs.

Evaluation of retention values of different telescopic crown attachment materials in implant retained overdenture (an in vitro study)

Evaluation of retention values of different telescopic crown attachment materials in implant retained overdenture (an in vitro study)

Evaluation of retentive force between stud and resilient telescopic crown attachment for implant-retained mandibular overdentures

Purpose This study aimed to evaluate the retentive force between stud and resilient telescopic crown attachments for implant-retained mandibular overdenture. Patients and methods A total of 20 male patients were selected from the Clinic of Removable Prosthodontics Department. Faculty of Dentistry, Sinai University (Kantara). Patients were divided into two equal groups. Group I (control group): patients were treated with two implants of 3.7 mm diameter and 13 mm length (in the canine regions), retaining mandibular overdentures with ball abutments, and by conventional maxillary complete dentures. Group II: patients were treated with two implants of 3.7 mm diameter and 13 mm length (in the canine regions), retaining mandibular overdentures with conical abutments with a 6° taper, and by conventional maxillary complete dentures. Retention force was recorded at the time of insertion (T0), 6 months (T6), and 12 months (T12) later. Results One-way anova revealed significant differences between the two groups in initial retention forces (T0). However, no significant difference was observed between the two groups at T6 and T12. Group II (telescopic attachment) was associated with significantly higher retention losses than Group I (ball attachment). In comparing the mean retention loss values for the two groups at different follow-up periods, significant differences were observed for both groups. Conclusion Within the limitations of this study, it can be concluded that: telescopic attachment with taper 6° can provide acceptable retention compared to ball and socket attachment during 12 months of overdenture use.

An overview of implant overdenture attachment systems

Implant-retained overdentures have revolutionized dental prosthetics, addressing the limitations of traditional removable dentures. These overdentures rely on attachment systems to anchor them to dental implants or abutments, improving stability, retention, and functionality. Common attachment systems include locator attachments, bar attachments, magnets, Hader clips, ERA attachments, telescopic crowns, and OT equator attachments. Each offers unique benefits and retention levels. Implant survival rates are influenced by various factors, including attachment type, but overall, attachment choice may not be the primary determinant of implant success. Attachment systems that evenly distribute forces, like bar attachments, contribute to implant stability. Marginal bone loss can affect implant stability and is influenced by attachment systems. Precision attachments, such as telescopic crowns, have shown reduced marginal bone loss in practice. Soft tissue complications, including inflammation and mucositis, vary by attachment but can be managed with proper oral hygiene. Retention, crucial for function, varies with attachment type and implant number. More implants generally improve retention, although it may decrease over time. Bar attachments typically provide superior retention. Maintenance is essential, with some debate over whether bar or stud designs entail more upkeep. Patient satisfaction is high with both bar and ball attachments, while magnets may pose retention issues. The choice of attachment depends on patient needs and clinical factors, with regular follow-up and maintenance essential for long-term success.

Success and complication rates of non-precious alloy telescopic crowns in a general dental practice

ObjectivesThis retrospective, single-center, practice-based cohort study aimed to analyze factors associated with the success of removable partial dentures retained by telescopic crowns (TRPD).Materials and methodsTRPD which were placed in a single practice of a practice-based research network were analyzed. Data from 139 patients (age (SD): 66 (11) years; 66 female) with 174 TRPD including 488 non-precious alloy telescopic crowns (TC) between 2004 and 2016 were included. TC without any technical complication were considered as successful, and as survived, if they were still in function at the last check-up. Multilevel Cox proportional hazard models were used to evaluate the association between clinical factors and time until failure.ResultsWithin a mean follow-up period (SD) of 4.2 (3.3) years (min–max: 1 day–12 years), 372 (76%) TC (AFR5years,TC-level: 5.0%) as well as 136 (87%) TRPD (AFR5years,TRPD-level: 5.1%) (“worst-case scenario”) and 150 (86%) TRPD (AFR5years,TRPD-level: 3.4%) (“best-case scenario”) were considered as successful. The main failure types were recementation (n = 39), endodontic treatment (n = 36), and extraction (n = 35). TC in male patients showed 1.6 times higher risk for failure than in female patients (95%CI: 1.1–2.4; p = 0.023). TC on premolars showed 2.2 times higher risk for failure than on incisors (95%CI: 1.1–5.0; p = 0.023) and TC in dentures with ≤ 3TC showed 2.1 times higher risk for failure than TC in dentures with > 3TC (1.3–3.4; p = 0.042). Furthermore, TC on the most distal tooth in an arch showed 2.4 times higher risk for failure than TC on a more mesial tooth (1.5–3.8; p < 0.001).ConclusionFor removable partial dentures retained by telescopic crowns, high success rates could be found after up to 12 years. Patient-level and tooth-level factors were significantly associated with failure.Clinical relevanceFor removable partial dentures retained by telescopic crowns, high success rates could be found after up to 12 years. Patient-level and tooth-level factors were significantly associated with failure.

The Effect of two different fabrication techniques on PEEK telescopic crowns to retain mandibular implant overdenture (In-vitro study)

The Effect of two different fabrication techniques on PEEK telescopic crowns to retain mandibular implant overdenture (In-vitro study)

Advanced method of rehabilitating edentulous Jaws: A review on telescopic denture.

Edentulism conducts to a recognized impairment of oral function with both aesthetic and psychological changes. These patients suffer from a multiplicity of problems with their dentures, such as insufficient stability, retention and pain during mastication. The rehabilitation of a part edentulous patient can be established using a wide range of prosthetic treatment options. The overdenture treatment uses a removable total denture that overlies retained teeth, tooth roots, or dental implants. In the literature it was shown that patients with removable overdentures supported and retained either by tooth roots or implants have more predictable prosthodontic outcomes. The aim of this review is to provide an overview on the overdenture with a focus on the tooth-supported telescopic overdenture. The literature research was performed in the Scopus, Web of Science, and Pubmed electronic databases. Document type was limited to papers written in English, without time restrictions. The Review was recorded in the international PROSPERO (International Prospective Register of Systematic Reviews) database with the following number CRD42022326415. A total of 256 articles published were found from electronic searches, Two independent reviewers carried out the screening and the selection process for the studies. First, duplicate citations were eliminated. Then, the two Authors independently screened the retrieved articles by title and abstract of each citation to determine its suitability for inclusion. Finally, 13 full-text articles satisfied the inclusion criteria. Prostheses supported by Frictional telescopic crowns offer an effective treatment alternative for patients with Severely reduced dentitions who do not want implant treatment or complete dentures.

An In-vitro Evaluation of Retention Force of All PEEK, All Zirconia and Zirconia-PEEK Telescopic Attachment for Mandibular Overdentures.

The objective of this study is to compare retention capacity of mandibular implant-supported overdenture with all zirconia, zirconia-PEEK, and all PEEK telescopic attachments. Sixty acrylic resin models of mandible were used. Telescopic attachment system was made up of all zirconia, all PEEK, and zirconia-PEEK. Evaluation of retention force was done using universal testing machine. Obtained data were statistically evaluated. Highest initial force value was obtained with zirconia-PEEK group. All PEEK and zirconia-PEEK groups showed significantly decreased final retention values in comparison to their initial values. Zirconia can be regarded as the material of choice for telescopic crown, whereas polyetheretherketone and zirconia-PEEK telescopic crowns showed retention loss over a period of time.

Impact of material combinations and removal and insertion cycles on the retention force of telescopic systems

ObjectivesA variety of dental materials are available for the fabrication of telescopic crowns. The aim was to investigate the impact of material combinations and removal and insertion cycles on their retention forces.Materials and methodsCAD/CAM-fabricated cobalt–chromium–molybdenum (CoCr) and zirconia (ZrO2) primary crowns were combined with polyetheretherketone (PEEK), polyetherketoneketone (PEKK), CoCr, and ZrO2 secondary crowns (four combinations included PEEK/PEKK secondary crowns in a thickness of 0.5 mm bonded to the CoCr tertiary construction), resulting in 12 different material combinations: CoCr–PEEK; CoCr–PEKK; CoCr–ZrO2; CoCr–CoCr; CoCr–PEEK 0.5; CoCr–PEKK 0.5; ZrO2–PEEK; ZrO2–PEKK; ZrO2–ZrO2, ZrO2–CoCr; ZrO2–PEEK 0.5; and ZrO2–PEKK 0.5 (n = 15 pairings per material combination). Pull-off tests were performed with a universal testing machine initially and after 500, 5000, and 10,000 removal and insertion cycles in a mastication simulator. Descriptive statistics with the Kolmogorov–Smirnov, Kruskal–Wallis, and Mann–Whitney U tests were computed (α = 0.05).ResultsThe tested parameters, material combination, and removal and insertion cycles had significant impact on the retention force values (p < 0.001). An increase in removal and insertion cycles was associated with a decrease in retention forces within CoCr and ZrO2 secondary crowns, regardless of the primary crown material. In contrast, PEEK and PEKK secondary crowns presented higher retention load values after 10,000 cycles than initially.ConclusionDifferent material combinations behaved differently after simulated removal and insertion regimens. This difference should be considered during treatment planning.Clinical relevanceTelescopic crown systems should be made of materials with predictable retention forces that do not deteriorate with time. The implementation of new materials and technologies facilitates reproducibility and time-saving fabrication.

The Use of Telescopic Crowns in Increasing the Retention of Esthetic Removable Partial Dentures

The Use of Telescopic Crowns in Increasing the Retention of Esthetic Removable Partial Dentures

Implant-Supported Overdentures: Current Status and Preclinical Testing of a Novel Attachment System.

Numerous attachment systems exist for implant-supported overdentures, with each having specific limitations in terms of retention, cost, wear, maintenance and cleanability. A retrospective analysis of patients restored with implant-supported overdentures using bars, telescopic crowns and Locator-type attachments was performed and the patients were interviewed. An in vitro strain gauge study compared telescopic crowns, Locator-type attachments and a novel flexible attachment system employing a shape memory alloy (NiTi) with respect to peri-implant strain development during insertion, loading and removal of an overdenture. A significantly lower number of attachment-related complications was observed in bars as compared to telescopic crowns (p = 0.00007) and Locator-type attachments (p = 0.00000), respectively. Greater overall patient satisfaction was noted in bar-retained restorations while Locator-type attachments led to lower levels of satisfaction regarding prosthesis retention. In vitro, telescopic crowns caused maximum strain development during prosthesis insertion and loading, while during removal this was observed in Locators with white retentive inserts. NiTi attachments caused significantly lower strain development during insertion as compared to telescopic crowns (p = 0.027). During loading, NiTi attachments caused significantly lower strain development than Locators with blue retentive inserts (p = 0.039). During removal, NiTi attachments caused significantly less strain development as compared to Locators with white retentive inserts (p = 0.027). Positional discrepancies between male and female attachment parts affected the retention and reaction force between both components, which may be minimized by using the novel NiTi attachment system. This may be beneficial in terms of component wear and implant loading.

Comparative analysis of stress and deformation distribution in implant supported telescopic systems made of different materials

Background/Aim. In implant prosthetics, there is an increasing use of materials that, with their mechanical characteristics, can alleviate the negative consequences of implant stress. The aim of this study was to conduct a comparative analysis of stress distribution and deformation of implant-supported telescopic systems and surrounding structures made of different materials using the finite element method. Methods. The 3D finite element models were prepared using the SolidWorks program (SolidWorks 2018, Concord, MA, USA). Two models of telescopic crowns with the characteristics of polyetherether-ketone (PEEK) polymer and cobalt-chromium (Co-Cr) alloy faceted with feldspar ceramics were used. The models were loaded with an axial force of 150 N in the region of the central fossa. The analysis of stress and strain distribution was per-formed by the finite element method in the Ansys software (ANSYS Workbench 16; Ansys Inc., Pittsburg, PA, USA). Results. Implant-supported telescopic crowns made of PEEK polymer significantly reduced stress in the implant and abutment neck area compared to the conventional Co-Cr crown veneered ceramic. At the level of bone structure, both models showed a concentration of stress at the level of the cortical bone, while the trabecular bone was significantly less exposed to stress. Under the same conditions, the degree of deformation of the secondary telescopic crown was more pronounced in models with PEEK polymer characteristics. Conclusion. Owing to their mechanical characteristics, PEEK polymers can be the materials of choice in the fabrication of superstructures on implants. Given that this in vitro study was accompanied by limitations, further research is needed to confirm the superior role of PEEK material in implant prosthetics.

Application of polyether ether ketone in obturator telescopic prosthesis fabrication: A case report

Introduction. The retention, stability, and plaque resistance of the obturator prosthesis significantly impact the improvement of the patient?s quality of life. The aim of this paper was to draw attention to the benefits of telescopic obturator prostheses made of polyether ether ketone (PEEK). Case report. We present an approach to the telescopic obturator fabrication using PEEK as the material of choice for the primary and secondary telescopic crowns, which are an integral part of the framework, in a 65-year-old patient with partial maxillectomy. The positioning of the teeth was made with a silicone key, and the featuring of the gingival part of the prosthesis was performed by a composite. Conclusion. PEEK is a polymer with good mechanical and chemical properties besides being bio-compatible. An obturator prosthesis made of this material does not incur enormous fabrication costs, and its satisfactory functionality contributes to the improvement of patients? lives.

Finite Element Study of Stress Distribution with Tooth-Supported Mandibular Overdenture Retained by Ball Attachments or Resilient Telescopic Crowns.

The removable partial denture must keep health of the remaining teeth and the supporting tissues through the distribution of chewing forces on the abutment teeth and alveolar process.This study aimed to evaluate stress distribution with canines-supported mandibular overdenture retained by two different attachment types: ball attachments or resilient telescopic crowns. Two 3-dimensional finite element models consisting of the cortical mandible bone, cancellous mandible bone, oral mucosa, canines, periodontal ligaments, the two attachment types, and overdenture were simulated. The models were imported into the mathematical analysis software Ansys Workbench V 15.0. All materials were considered to be homogeneous, isotropic, and linearly elastic. A vertical bilateral load of 120 N was applied to the central fossa of the first molars. The von Mises stress was calculated for canines, cortical, and cancellous bone. The maximum von Mises stress of the ball attachments model was 35.61, 4.28, 7.82, and 1.29 MPa for canines, cortical alveolar bone of canines, cortical alveolar bone at the distal end of the overdenture, and cancellous alveolar bone of canines, respectively. The maximum von Mises stress of the resilient telescopic crowns model was 39.22, 4.74, 7.06, and 1.05 MPa for canines, cortical alveolar bone of canines, cortical alveolar bone at the distal end of the overdenture, and cancellous alveolar bone of canines, respectively. Resilient telescopic crowns distribute the stresses between canines, alveolar bone of canines, and overdenture supporting alveolar bone. Ball attachments transfer less stress to the canines and cortical alveolar bone of the canines, but more stress to the cancellous alveolar bone of canines and alveolar bone at distal end of the overdenture. Resilient telescopic crowns are preferred over ball attachment when the abutment teeth have good periodontal support.

Biomechanical Performance of PEEK and Graphene-Modified PMMA as Telescopic Removable Partial Denture Materials: A Nonlinear 3D Finite Element Analysis.

To assess stress and deformation in telescopic removable partial denture (RPD) frameworks manufactured with polyether ether ketone (PEEK) or graphene-modified polymethyl methacrylate (PMMA), as well as the stress of the underlying mucosa, via nonlinear 3D finite element analysis. The 3D model of a full mandible was merged with a 3D-scanned Kennedy Class I model with bilaterally missing molars. The tissues, the telescopic crowns, and the RPD framework were designed and created using dental CAD software. The model was duplicated, and two materials-PEEK and graphene-modified PMMA-were assigned to the telescopic crowns and their frameworks. A force of 200 N was applied perpendicularly to the molars, and constraints were placed in the mandibular ramus and the inferior border. The generated von Mises stress and deformation of the frameworks, as well as the stresses of the telescopic crowns and mucosa, were also assessed. Statistical analysis of the differences between the tested materials was conducted via an independent samples t test at (α = .05). The von Mises stresses of the telescopic crowns and their frameworks in the graphene-modified PMMA model were significantly higher than in the PEEK model. In contrast, the deformation of the telescopic RPD framework of the PEEK model was significantly higher than the graphene-modified PMMA model. The stresses of the mucosa in both models showed an insignificant difference. PEEK material showed better biomechanical performance than the graphene-modified PMMA in telescopic RPDs.

Double-Crown Prosthesis Retention Using Polyetherketoneketone (PEKK): An In Vitro Study.

To assess the retentive force of telescopic crowns using polyetherketoneketone (PEKK) high-performance polymer in relation to conventional materials over a long period of time in an in vitro setting. Thirty-six sets of primary and secondary crowns were fabricated as per the double crown-retained prostheses approach. Six samples were included in each of the five test groups (1: zirconia/PEKK [Zr/PEKK]; 2: titanium/PEKK [Ti/PEKK]; 3: cobalt-chrome/PEKK [CoCr/PEKK]; 4: PEKK/PEKK; and 5: gold/PEKK [Au/PEKK]) and the single control group (gold/galvano-gold [Au/GA]). The insertion-removal test was performed for 20,000 cycles, and the surface condition was observed. Retentive forces were analyzed using two-way ANOVA (α<0.05). The retention forces in groups Zr/PEKK and Ti/PEKK significantly decreased over time (group 1: p = 0.035 and group 2: p = 0.001), whereas retentive force increased significantly in groups PEKK/PEKK, Au/PEKK, and control (group 4: p = 0.001, group 5: p = 0.008, and control: p = 0.042). Similar wear was observed on the primary crown in groups PEKK/PEKK, gold/PEKK, and control. Groups PEKK/PEKK and Au/PEKK showed a transition of retentive force similar to the control group. Groups PEKK/PEKK and Au/PEKK had similar wear on the surface compared to control. Therefore, PEKK has a promising clinical potential.

Comparative Stress Analysis of Polyetherketoneketone (PEKK) Telescopic Crowns Supported by Different Primary Crown Materials

The present study aimed to investigate the stress distribution of secondary telescopic crowns made of polyetherketoneketone (PEKK) combined with different primary crown (PC) materials (Zirconia, CoCr, Titanium, and PEKK) using finite element analysis. The geometric model was composed of bone tissue, periodontal ligament, root dentin, cement layer, primary crown, and secondary telescopic crown (SC). A total of four models were evaluated in which the secondary crowns were simulated in PEKK. The models were designed in CAD software and exported to the computer aided engineering software for the statistic structural analysis simulation. The materials were considered isotropic, with linear behavior and elastic properties. The model was fixed in the bone base and the load was applied at the occlusal surface of the crowns with 600 N. The results were required in von-Mises stress for the primary crown, secondary crown, cement layer, and Equivalent Strain to the periodontal ligament and bone tissue. Results show that the material influenced the stress distribution. The higher the PC elastic modulus, the higher the stress magnitude on the SC and cement layer. In the present study, the use of milled high-density polymer for primary crown presented a promising biomechanical behavior as an alternative material for double-crown design.

A Case Report on Implant-Supported Telescopic Prosthesis—A Gerodontic Enhancement

One of the most challenging and demanding endeavors in the field of prosthodontics is the rehabilitation of an edentulous mandible. Implants have been used to support mandibular or maxillary prosthetic rehabilitation. Advantages of using implants are increased retention, increased chewing ability, and also easy access to oral hygiene procedures. For decades, the use of telescopic and conical crowns are in practice to connect natural teeth and not many cases have been reported in the literature of telescopic crowns placed on implants to support the prosthesis. Telescopic crowns provide the best possible distribution of force to the abutment teeth and can improve the patient’s oral health-related quality of life. The use of telescopic crowns as attachments for implant-supported overlying prostheses may be a viable treatment option for edentulous mandible. The functional and the aesthetic enhancement by telescopic retainers are favorable features for many challenging situations.This case report discusses a 60-year-old male, who reported to the department of prosthodontics with three implants and two bi-cortical screws that were placed in a completely edentulous mandibular arch by a private practitioner one year back and this situation was prosthodontically managed by us with an implant-supported telescopic removable prosthesis.