Telescopic Crowns Research Articles

Periodontal prosthesis on medically compromised patient with few remaining teeth: hybrid telescopic double crown with friction pin method

치아가 얼마 남지 않은 부분 무치악 환자들에 있어 이중관(Double crown)을 이용한 치료의 성공적인 결과에 대해서 여러 문헌에서 보고 되고 있다. 이중관 가철성국소의치(Double crown removal partial denture)는 잔존치의 치주적인 상태가 좋지 않은 환자에게 치료의 대안이 될 수 있다. 이중관 가철성 국소의치는 특히 치주상태가 좋지 않고, 임플란트를 식립하기에는 의과적으로 문제가 있는 환자(Medically compromised patient)에게는 수술에 대한 부담 없이 치료할 수 있어 심리적이고 경제적인 이점이 존재한다. 본 증례에서는 상악은 다수의 치아가 잔존하여 고정성 보철물로 수복이 가능한 상태였고, 하악은 소수 잔존치만 남아있고 치주 상태가 매우 불량하여 잔존치를 이용한 클라스프 가철성 국소의치로는 수복하는 것이 거의 불가능하였다. 또한 환자는 1년 전에 하악 전치부 부위의 골수염으로 인한 수술병력으로 임플란트 식립이 어려운 상황이었다. 이러한 악조건에서 하악의 소수 잔존치를 이용한 이중관 의치는 2년이상의 기간동안 기능적, 심미적인 면에서 만족스러운 결과를 얻었기에 이를 보고하고자 한다. 【Successful results of treatments using double crown prostheses for the partially edentulous patients who have a few remaining teeth have been reported in several journals. A double crown removable partial denture can be an alternative treatment for the patients with a poor periodontal condition of remaining teeth. Since a double crown removable partial denture can be applied without the risk of surgical operation to the medically compromised patients with a poor periodontal condition which is inadequate for dental implants, it has psychological and economical advantages. In this case, there were sufficient remaining teeth to be restored with fixed prostheses in maxilla, while there were a few remaining teeth with a very poor periodontal condition so that it was almost impossible to restore with a clasp removable partial denture using these remaining teeth in mandible. In addition, the patient had the medical history of surgical operation due to osteomyelitis in the mandibular anterior areas a year ago, thus difficult to conduct an implant placement. The main objective of this report is to introduce our case because a double crown partial denture using a few mandibular remaining teeth showed satisfactory results in functional and esthetical aspects during more than two years follow-up period in this unfavorable condition.】

Anterior Splint Bar versus Telescopic Crowns as Retainers for Distal Extension Bases with Anterior Modification Space : Strain Gauge Analysis

Anterior Splint Bar versus Telescopic Crowns as Retainers for Distal Extension Bases with Anterior Modification Space : Strain Gauge Analysis

Use of conical telescopic crowns in a partially edentulous patient: A case report

Use of conical telescopic crowns in a partially edentulous patient: A case report

A 3-Year Prospective Clinical Study of Telescopic Crown, Bar, and Locator Attachments for Removable Four Implant–Supported Maxillary Overdentures

To evaluate telescopic crown (TC), bar, and locator attachments used in removable four implant-supported overdentures for patients with edentulous maxillae. A total of 30 maxillary edentulous patients were enrolled in a 3-year prospective study. Ten patients (group A) were treated with overdentures supported by TCs, 10 patients (group B) with overdentures supported by bar attachments, and 10 patients (group C) with overdentures supported by locator attachments. A total of 120 implants were used to restore oral function. During the 3-year follow-up period, implant survival and success rates, biologic and mechanical complications, prosthodontic maintenance efforts, and patient satisfaction were evaluated. All 30 patients were available for the 3-year follow-up and exhibited 100% implant survival and success rates. Peri-implant marginal bone resorption was not statistically significant for the three groups. There were lower plaque, bleeding, gingiva, and calculus indices in group C compared with groups A and B. The number of prosthodontic maintenance visits revealed eight complications in the TC group, seven complications in the bar group, and four complications in the locator group. However, there were no differences in the clinical effects of the overdentures in the three groups. Within the limits of this prospective study, it was concluded that the locator system produced superior clinical results compared with the TC and bar attachments in terms of peri-implant hygiene parameters, the frequency of prosthodontic maintenance measures, cost, and ease of denture preparation. However, longer-term prospective studies are required to confirm these results.

Effect of different implant positions on strain developed around four implants supporting a mandibular overdenture with rigid telescopic copings.

To evaluate and compare the effect of three different implant positions on strain developed around four implants supporting a mandibular overdenture with rigid telescopic attachments. Three experimental acrylic resin overdentures were fabricated on three edentulous mandibular acrylic models. Four implants were placed in each model. According to the implant positions, the models were classified into three groups: in group I (quadrilateral design) the implants were placed at canine and first molar areas; in group II (curved design) the implants were placed at canine and second premolar areas; and in group III (linear design) the implants were placed at lateral incisor and first premolar areas. Overdentures were connected to the implants with rigid telescopic attachments. Eight linear strain gauges were bonded to the acrylic resin around each implant at two sites (mesial and distal). Strains were measured for anterior (lateral incisor and canine) and posterior (premolar and molar) implants at both mesial and distal sites during bilateral and unilateral load applications. For bilateral and unilateral load applications, group II recorded the highest strain values while group I recorded the lowest. In group II and group III, strain values at distal sites were significantly higher than values at mesial sites. Strain values of posterior implants were significantly higher than values of anterior implants in all groups. The greatest strain values were recorded at the loading side during unilateral load application. Quadrilateral design showed minimal peri-implant strain compared to curved or linear designs. This design may be recommended when rigid telescopic crowns are used to connect mandibular overdentures to four implants.

Conical telescopic crowns in modern prosthodontic procedures

Conical telescopic crowns in modern prosthodontic procedures

Mahkota teleskopik sebagai retainer alternatif gigitiruan lepasan Telescopic crown as alternative retainer of removable denture

In making removable denture, some aspects must be considered: retention, stabilization, support, comfort, andaesthetic. Retention plays an important role in the success of a removable denture. Retention can be obtained from theundercut area, or friction of the denture’s components to the abutment or abutment. Clasp as a retainer, both of metalcasting and wire have been frequently used in the removable partial denture. The clasp has some shortcomings in itsusing, namely color of the metal can sometimes interfere with the aesthetic of the wearer and cannot be placed on teeththat have experienced extensive caries. Telescopic crown as retainer has several advantages, which can be used oncrown of abutment that has experienced extensive caries or tooth that will be an abutment but have endodontic-treated.On telescopic crowns, retention is obtained from the friction between the primary crowns against secondary crown thatserves as a retainer. This case report describes two cases of a removable denture with a metal framework using atelescopic crown on one tooth that serves as a retainer in the case of one-side free-end edentulous.

Comparison of the effects of friction varnish and electroforming on the retention of telescopic crowns

Methods to improve the retention of telescopic crowns, including the application of friction varnish and electroforming, are available. However, information about their efficiency is limited. The purpose of this study was to compare the influence of 2 different friction varnishes and an electroforming method on the retention of telescopic crowns. Thirty inner and outer crowns were fabricated from cobalt-chromium-molybdenum alloy having lengths and cervical diameters of 6 mm, 2-degree tapers, and shoulder margins of 1 mm. Fifty-μm thick layers were removed from the internal surfaces of the outer crowns with a vertical machining center to simulate wear. The retentive forces of these specimens were measured with a testing machine. FGP friction varnish (FGP Friction-Fit-System), SD friction varnish (Servo-dental), and an electroforming method (GES\Gold Electroforming System) were applied to the specimens. After the application of the 3 methods, retention values were measured, and the results analyzed with 1-way ANOVA, paired sample t test (α=.05). The increase in the retentive forces of all specimens was statistically significant (P<.01). The mean retentive forces increased from 3.6 N to 9.8 N for group FGP, 3.6 N to 4.6 N for group SD, and 3.7 N to 6.0 N for group EF. Group FGP was significantly different from group SD and group EF (P<.05), and no significant difference was observed between group SD and group EF. Mean standard deviation values of retentive forces for group FGP before, FGP after, SD before, SD after, EF before and EF after is 0.5, 2.7, 0.6, 1.3, 0.8, 2.3, respectively. Group FGP showed the maximum retention values. Group EF showed higher retention values than group SD.

Retention of overdentures supported on telescopic crowns

Retention of overdentures supported on telescopic crowns

A 5- to 8-year Retrospective Study Comparing the Clinical Results of Implant-Supported Telescopic Crown Versus Bar Overdentures in Patients With Edentulous Maxillae

The objective of this study was to compare implant survival and success rates, peri-implant parameters, and prosthodontic maintenance efforts for implant-supported telescopic crown overdentures and bar overdentures to restore maxillary edentulism. This retrospective clinical study involved patients with maxillary edentulism who were fitted with implant-supported overdentures from January 2004 to June 2007. During a 5- to 8-year follow-up period, the implant survival and success rates, biologic and mechanical complications, prosthodontic maintenance, and patient satisfaction were retrospectively analyzed. The data were evaluated statistically and P < .05 was considered to be statistically significant. Forty-four patients with maxillary edentulism received implant-supported removable overdentures. Twenty-one patients chose telescopic crown overdentures and 23 patients chose bar overdentures. A total of 41 patients and 201 implants were available for follow-up. The implant survival and success rates, average bone resorption, and subjective patient satisfaction scores showed no difference between the telescopic crown and the bar overdenture group at follow-up. However, there were higher values for Plaque and Calculus Indexes in the bar group compared with the telescopic crown group, and these values showed a statistically significant difference annually from the 3-year follow-up (P < .05). Each year, the number of prosthodontics maintenance procedures per patient did not significantly differ between the telescopic crown (approximately 0.36 to 0.58) and bar groups (approximately 0.30 to 0.49) (P = .16). Although there were higher plaque and calculus levels in the bar group and more maintenance was required for the telescopic crown group, overdentures provided a healthy peri-implant structure for implants in both groups. Implant-supported telescopic crown or bar overdentures can provide a good treatment option for patients with edentulous maxillae.

Implant placement under existing removable dental prostheses and its effect on oral health‐related quality of life

One aim of this prospective clinical study was to measure the effects of strategicimplant placement under removable partial dental prostheses (RPDPs) and among removable complete dental prostheses (RCDPs) on oral health-related quality of life (OHRQoL). Twenty-three patients participated in this study restored with RCDPs (n = 12) or RPDPs retained by telescopic crowns with 1-2 abutment teeth (n = 11). The total number of abutments was increased to 5-6 (maxilla) or to 4 (mandible) by placing implants in strategically advantageous regions. Ball attachments were attached to the implants and integrated in the existing denture. The Oral Health Impact Profile (49 questions) was completed by patients before implant placement, at baseline (integration of ball attachments), and during 12- and 24-month follow-up visits. There were marked reductions of impacts in both groups when comparing pre-treatment scores and scores at baseline (P < 0.0001), 12-month (P < 0.0001), and 24-month follow-up visits (P < 0.0001), respectively. For none of the visits, a significant difference between the two groups was detected (P > 0.05). It can be concluded that a strategic placement of implants under the existing dental prostheses improves OHRQoL in both treatment groups.

Scarring and chronic ulceration of the floor of the mouth

CASE REPORT A 63-year-old male patient was first seen for evaluation of chronic intraoral mucosal lesions and ulcerations. His medical history revealed that 30 years earlier, he had experienced Hodgkin lymphoma (HL), which had successfully been treated by chemotherapy. The patient reported that oral lesions apparently developed soon thereafter and had been present periodically. In addition, he had been experiencing itchy cutaneous lesions on the upper trunk and arms for many years, which he claimed had been treated unsuccessfully by corticosteroids. He also had recurrent depressive episodes, which had been treated medically. Clinical examination disclosed a deep ulcerative lesion measuring 3 cm in diameter on the left anterior floor of the mouth (Figure 1). The carunculae sublinguales could not be identified, and the anterior floor of the mouth demonstrated scarring and induration on palpation. Furthermore, the buccal mucosa showed some bilateral scarring, and an erosive lesion was visible in the left buccal plane (Figure 2). The maxilla was edentulous, and in the mandible, telescopic crowns were fixed on molars bilaterally. The complete maxillary denture and mandibular overdenture were welladapted. Excoriations, erosions with crusts, and postinflammatory hypopigmentations were found on the skin of the patient’s arms, shoulders, thorax, and neck (Figure 3).

Multidisciplinary Approach for Esthetic, Functional, and Quality-of-Life Outcome in Soft Palate Cleft Patient

The fabrication of a Suersen obturator prosthesis with titanium framework is described in the case of a 43-year-old man with congenital absence of the soft palate. The patient revealed an open soft palate, bilateral cleft lip and palate, Angle Class III dental malocclusion, and anterior and posterior crossbite. He was treated with a multidisciplinary approach. A Dolder bar was fabricated between the maxillary canines, and telescopic crowns were prepared for maxillary premolars. Angle Class III tooth relation was readjusted to tooth-tooth relation; closure of the nasopharynx and oropharynx was performed by Suersen method, which improves speech.

The prosthetic rehabilitation of a panfacial fracture patient after reduction: A clinical report

Panfacial fractures involve trauma to the lower, middle, and upper facial bones and often require a team approach for management. Early and complete restoration of preinjury facial contours and function should be the goal of the oral and maxillofacial surgeon and the prosthodontist. When the intraoral landmarks are lost, overall facial anatomic landmarks can be used to restore the oral cavity. A patient with complex clinical panfacial fractures, including a vertically and horizontally malpositioned native alveolar bone and severe facial asymmetry, is presented. A functional and esthetic rehabilitation was successfully accomplished by using a partial removable dental prosthesis retained with telescopic crowns and magnetic attachments in the maxilla and osseointegrated implants to support a definitive dental prosthesis in the mandible.

Rehabilitation of a Maxillectomy Case with Telescopic Crowns: A Case Report

Prosthodontic rehabilitation of acquired defects of the maxilla is a challenge in terms of reestablishing oronasal separation. Most of the times these goals are met by means of obturator prosthesis. Preservation of the remaining hard and soft tissues in such patients is very much essential in order to have a good retention, stability and support for the prosthesis. It is very much imperative to fabricate a prosthesis to provide proper function to the patient. Various techniques have been developed to enhance the retention and stability of the prosthesis, some of them being extension of the obturator bulb into the undercuts within the defect, use of magnets, implants etc. Telescopic crowns have been an adjunctive utility to prosthetic dentistry since a very long time. The biomechanics of telescopic crowns aid in providing a good retention and stability to the prosthesis. In the following clinical report a patient with a status of Subtotal Hemi Maxillectomy is presented in whom telescopic copings were incorporated into the cast hollow bulb obturator to enhance the retention and stability of the prosthesis.

Clinical and laboratory stages of manufacturing an overdenture supported on zirconium telescopic crowns

Clinical and laboratory stages of manufacturing an overdenture supported on zirconium telescopic crowns

Wear of double crown systems: electroplated vs. casted female part

ObjectivesThe wear of telescopic crowns is a common problem often reducing the patient's satisfaction with the denture and resulting in a renewal of the denture. The study aims to compare the wear behavior of conical crowns using electroplated copings (group E) with standard telescopic crowns with cast female parts (group C). Material and Methods10 conical crowns were milled for each group of a cast gold alloy. The specimen of group E had a conicity of 2º. The cast secondary crowns of group C had a 0º design. The electroplated coping was established by direct electroforming. An apparatus accomplishing 10,000 wear cycles performed the wear test. The retentive forces and the correlating distance during insertion and separation were measured. The wear test was separated in a start phase, an initial wear phase and the long term wear period. The retention force value and the force-distance integral of the first 0.33 mm of each cycle were calculated. ResultsThe retentive forces were significantly higher for group E and the integrals were significantly lower for this group except the integral at cycle 10,000. The changes of retention force and integral did not differ significantly between both groups in all phases. The change of the integrals as well as the integral at the particular cycles showed higher interquartile distances for group C. ConclusionsWithin the limitations of this study the tested conical crowns showed clinically acceptable retentive properties. The values reached a range comparable to retentive elements tested in recent literature. The values of group C showed higher ranges. The force measured for group E was significantly higher than for group C but the integrals showed an opposite tendency. The results indicate that an exclusive analysis of the force is not sufficient as the integral is not equivalent to the force although it describes the retentive property of the system in a better way than the force over a distance is described. Both systems seem to be suitable for clinical practice.

Assessment of telescopic denture's settling in phase duration

Introduction. Double telescopic crowns are connecting elements of partial dentures and are considered to be prosthetic devices of high aesthetic and biological value. Their basic drawback is the assessment of retention force value which has to be strong enough to balance the opposite forces but, nevertheless, must not result in harming the periodontal tissue of retention teeth while taking the denture off. The retention force is the highest immediately after the denture's construction and is progressively declining until the end of the 'settling in phase', i.e. until the retention force value becomes well-established. Aim of the study was the measurement of the overall retention force of completed telescopic dentures and a survey of 'settling in phase' duration. Methods. The measuring was conducted on 20 telescopic dentures consisting of 2, 3 or 4 telescopic crowns made of gold alloy type IV and executed by dynamometer. Results. An optimal retention force was detected in only 37% of telescopic dentures. An insufficient retention force was observed in 16%, while in the remaining 47% an excessive force was detected. In the largest number of dentures (35%) the settling in phase began after 33 cycles, which shows that this phase takes on average 10,6 days. Conclusion. The 'settling in phase', during which retention force becomes stabilized, is completed in the first ten days after the delivery of the completed telescopic denture.

Telescopic overdentures with cercon primary coping and gold galvano secondary coping

Overdenture treatment provides an esthetic and functional result that allows proper access for hygiene and maintenance. In addition, with their improved strength, zirconia ceramics may be used to restore removable partial denture abutments in areas previously limited to metal or metal-ceramic restorations. The electroforming process makes for a viable, convenient, and economic alternative to cast metal substructures. However, limited data are available on the use of telescopic crowns on implants. Compared with the use of fixed implant-supported dentures, this treatment modality may improve esthetics and oral hygiene access, reduce the need for implants, and provide sufficient denture support in cases where single abutments have failed. Furthermore, the high retention obtained with telescopic crowns leads to good mastication and phonetics.

Erratum: A FEM study on stress distribution of tooth-supported and implant-supported overdentures retained by telescopic crowns

Erratum: A FEM study on stress distribution of tooth-supported and implant-supported overdentures retained by telescopic crowns