Attachment Overdenture Research Articles

Attachment Retained Tooth Supported Overdentures: A Case Series

Present case series describes the three different types of attachments use for tooth supported overdenture for prosthetic rehabilitation. Loss of teeth causes continuous resorption of the bone leading to a compromised treatment. Retaining two or more natural teeth can be used as an abutment for prosthetic rehabilitation of partial edentulism arches. Preventive prosthodontics includes tooth supported overdentures which preserves natural teeth, roots and maintains propioception. Depending upon the interarch distance available various types of attachments can be used to enhance the retentive factors. The first case (71-year-old female patient) describes the use of telescopic attachment overdenture on 33, 43 with available interarch space of 15 mm in mandibular arch. The second case (62-year-old female patient) describes the use of ball attachments overdenture on 34 and 35 with available interarch space of 13 mm in mandibular arch. The third case (60-year-old female patient) is about equator attachment overdenture on 33, 43 with available interarch space of 12 mm in mandibular arch. Use of telescopic, ball and equator attachments for tooth supported overdentures has enhanced the retention, stability, function and aesthetic outcome of the removable prosthesis in mandibular arch. The natural teeth provide additional support, stability and retention of the overdenture than the edentulous ridges alone which is particularly advantageous for mandibular arch.

Stress Analysis of Implant-Supported Removable Partial Denture with Anterior Fixed Prostheses and Conventional Implant-Supported Overdentures in the Edentulous Mandible

Aim: To compare new design implant-supported removable partial dentures retained with anterior fixed prosthesis with a conventional locater and bar attached implant overdenture prostheses retained by two or four implants via photoelastic stress analysis. Materials and Methods: Seven edentulous mandibuler acryclic models prepared and divided into two main groups; two to four implant models, subgroup separation as stated; for two implant models overdenture with locator attachment, crown design retained removable prosthesis with clasp retention, bridge design retained removable prosthesis with clasp retention, bridge design retained removable prosthesis with precision attachment retention; and for four implant models prosthesis with bar attachment overdenture, fixed bridge design retained removable prosthesis with clasp retention, fixed retained removable prosthesis with precision attachment retention. A 300 N load was applied to the first premolars. Photoelastic stress analysis method that is a specific method concerning stress visualization, and does not require statistical analysis, was used. The stress distributions were seen in optically using a poloriscope. Results: In the models with two implant-retained removable partial dentures, the stress distribution was found to be lower than that with the four implant-retained removable partial dentures. Nonsplinted implants caused high stress around the distal implant on the loading side. Conclusion: The stress loads were transmitted to other implants by splinting. Implant-supported removable partial dentures with an anterior fixed prosthetic design show lower stress distributions compared with bar retained prosthesis. These dentures appear to be advantageous in terms of stress transmission.

Full mouth rehabilitation with maxillary equator® attachment over denture and mandibular hybrid denture - A case report

Implant-supported prosthodontic rehabilitation of total edentulism remains the most complex restorative challenges. The main reason being the number of variables that affect both the aesthetic and functional aspects of the prosthesis. A hybrid denture or the ‘Toronto prosthesis’ is one that is fabricated over a metal framework and retained by screws threaded into implants. This article presents the fabrication of implant-retained maxillary Equator® attachment overdenture opposing mandibular implant-retained hybrid prosthesis. A total of four implants (Equinox® Myriad plus) were placed the maxillary arch and six implants (Equinox® Myriad plus) in the mandibular arch. The patient's occlusal vertical dimension, centric relation, aesthetics and phonetics were determined and maintained throughout the restorative process. This case report describes the management of a completely edentulous patient with a mandibular implant-supported fixed prosthesis and maxillary implant-retained overdenture with Equator® attachment.

Effect of Using Zirconia and Metallic Bar Attachment Overdentures on the Supporting Structures of Mandibular Edentulous Ridge Area (Randomized control Trial)

Effect of Using Zirconia and Metallic Bar Attachment Overdentures on the Supporting Structures of Mandibular Edentulous Ridge Area (Randomized control Trial)

Mandibular implant-natural tooth retained overdenture using magnetic attachment with stress breaker

Overdenture has the advantage of improving the stability and retention of the denture but the abutment may be easily affected by caries or periodontal disease and the thin denture can be easily broken. The magnetic attachment overdenture has a high vertical retention but a low horizontal retention, thus, exerting a less disruptive force to the abutment or implant and shows less abrasion or damage compared to other mechanical retainers. Denture fractures in overdenture is caused by the thin denture base as the attachment is inserted, but it may also be caused by the difference in detrusion between soft tissue and hard tissue, and between an implant and a natural tooth. To compensate this shortcoming, a magnetic attachment with a silicone ball inserted in the magnet was developed as we report a successful case using this specific type of magnetic attachment overdenture.

Effect of attachment types and number of implants supporting mandibular overdentures on stress distribution: A computed tomography-based 3D finite element analysis

The objective of this study was to calculate stresses in bone tissue surrounding uncoupled and splinted implants that are induced by a bite force applied to the mandible and to determine whether the number of mandibular overdenture supporting implants in mandibular bone influence the stress distribution. A human adult edentulous mandible retrieved from a formalin fixed cadaver was used to define the geometry of finite element (FE) model and the FE model was verified with experimental measurements. Following the FE model validation, three different biting situations were simulated for the 2-, 3- and 4-implant retentive anchor as well as bar attachment overdentures under vertical loading of 100N. As a result of the analyses, it was concluded that an increment in implant number and the splinted attachment type tended to cause lower stresses and the use of two single attachments seems to be a safe and sufficient solution for the treatment of mandibular edentulism with overdentures.

Mandibular Hader bar attachment overdenture wearers: A five-year longitudinal clinical evaluation by electromyographic analysis

IntroductionElectromyography is used to evaluate the muscle activity of temporalis and masseter muscles in a comparative clinical research on effectiveness of masticatory cycle by conventional overdenture and use of overdenture with Hader bar attachment for five years established on a scientific level and is first of its kind. AimThe purpose of this study is to determine the response of co-ordination of stomatognathic system and the functional status of long-term overdenture use, which can be recorded in EMG. Material and MethodsTen patients were treated with maxillary conventional complete denture and mandibular overdenture. Electrical activity of masseter and temporal muscles were obtained in 3 groups. (Gp. I) After insertion of conventional overdenture with copings; (Gp. II) Overdenture with Hader bar attachment and (Gp.III) five years of use of overdenture with Hader bar attachment. Results and conclusionThe mean and standard deviation for all the patients showed an increase in muscular activity of temporalis and masseter muscles after long-term rehabilitation (x = 0.405; 0.407 and s = 0.0668; 0.1344 respectively, p = 0.0042 and 0.0074 which is <0.05). This study concludes that overdenture with Hader bar system, after five years of function provide a sound justification for a viable alternative treatment modality to provide overdenture with attachment service to patients.

クラスプ義歯による発音障害に対して磁性アタッチメントを応用した１症例

A 50-year-old female who wore a cast-clasp-supported removable partial denture (RPD) complained of speech disturbance, because the clasps disturbed her tongue movement during speech. She wished to receive dental implant treatment, but it was difficult to solve the esthetic problem by the planned implant-supported fixed partial denture. Therefore, the RPD (overdenture) supported by magnetic attachments was inserted to recover the speech disturbance. The treatment outcome of this patient was evaluated with a self-administered questionnaire. The results suggested that the RPD with magnetic attachments improved the patient's pronunciation, esthetics and quality of life. It was suggested that the magnetic attachment overdenture effectively solved the speech disturbance.

Influence of Attachment Systems on Load Transfer of an Implant‐Assisted Maxillary Overdenture

This photoelastic study compared the load transfer characteristics of 2 retention mechanisms in an implant-assisted overdenture prosthesis. Four implants were incorporated into a photoelastic model of a moderately resorbed edentulous human maxilla. Two retention mechanisms were studied by changing components on the same model and the palateless overdenture. The retention mechanisms studied were bar splint with anterior clip and distal resilient attachments, and solitary ball/O-ring attachments. Loads, ranging from 1.4 to 14.4 kg, were applied to the palatal incline of central incisors and buccal incline of premolars with and without balancing contacts. Stresses developed around all the implants under each loading condition were photographed in the field of a circular polariscope. With both retention mechanisms, protrusive and laterotrusive loads without balancing contacts caused instability of the overdenture, producing minimal stress around the implants in the supporting structure. High intensity stresses indicating intrusion of the posterior implants were noted when the bar/distal resilient attachment overdenture had balancing contacts for protrusive and laterotrusive loads. The posterior implants of ball/O-ring attachment overdenture exhibited high intensity stresses indicating not only intrusion, but also bending, when the occlusion was balanced. Balanced occlusion was required in both retention mechanisms for stability of the implant-assisted overdenture when clinically acceptable loads were applied. The protrusive and laterotrusive loads were not distributed equitably in either mechanism, since highest stresses occurred at the posterior implants.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part II. Comparisons of masticatory performance

Statement of problem. Convincing evidence is lacking to demonstrate the functional superiority of mandibular implant-supported overdentures over conventional dentures. Purpose. This randomized clinical trial was conducted to compare masticatory functional effectiveness of mandibular implant-supported overdentures and conventional dentures in diabetic denture wearers with clinically acceptable metabolic control. Methods. A total of 102 edentulous diabetic patients, treated with or without insulin, were randomized to receive a new maxillary and either a mandibular conventional denture or an implant-supported overdenture. Treatment was completed in 89 patients, 37 with conventional dentures and 52 with Hader bar-clip attachment overdentures supported by two IMZ implants. Besides data from medical and dental histories, oromaxillofacial examinations, and questionnaires, masticatory tests were performed by patients before and at 6 and 24 months after treatment completion. Although 78 patients (28 in the conventional, 50 in the overdenture group) performed tests at 6 months after treatment, 68 (25 in the conventional, 43 in the overdenture) had performance data for both entry and 6-month posttreatment intervals. Results. The two treatment groups were highly comparable in terms of general characteristics, quality of original dentures, tissue support, and past denture experience. No significant differences were found between patients treated for diabetes with or without insulin. All four masticatory performance scores with original dentures were higher in the conventional denture group than the overdenture group. The posttreatment performance scores for the two treatment groups became similar because of the higher gains in the overdenture group. Patients with low initial performance scores showed greater posttreatment gains with both conventional dentures and overdentures. Conclusions. The implant-supported overdenture showed no significant advantage over the conventional denture for improving the ability to comminute food in this group of diabetic patients with higher than average initial functional levels observed for other groups of denture wearers in previous studies. (J Prosthet Dent 1998;79:632-40.)

Prospective clinical evaluation of mandibular implant overdentures: Part II—patient satisfaction and preference

In a crossover experimental design, a prospective clinical study was performed with 17 subjects with existing complete dentures. After data collection, two implants were placed bilaterally in the anterior mandible. Conventional dentures were modified into implant overdentures by use of O-ring and magnet attachments. Each attachment was maintained with each subject for 6 months. Subjects responded to patient satisfaction and preference questionnaires about the conventional denture and each attachment. Subjects were satisfied with both attachment overdentures but showed a strong preference for the O-ring. Both attachments resulted in a significant increase in patient satisfaction when compared with the conventional denture.

Removable Partial Overdentures with Mechanical (Precision) Attachments

Mechanical attachments for overdentures have been available in various forms for over a century. The explosive interest in osseointegration and the effort on the part of the profession to avoid the complete denture as a treatment modality has stirred the interest in positive retentive elements for overdentures represented by the mechanical stud and bar attachments. The cited references provide a resource as a trouble-free guide in the selection and use of the various stud and bar attachment systems. The clinical examples show a pattern of application not generally discussed by the manufacturers, illustrating the simplicity of use with the options for all attachments including magnets. The discussion on magnets comes from 9 years of clinical experience. Rare earth magnets provide excellent adjunct retention, and their assembly follows the same protocol and complexity as stud attachment systems. All magnets, at the present state of the art, have a corrosion potential with the exception of the Laser Sealed Units (Golden Dental, Golden, CO). Finally, the mechanics of the attachment overdenture serves as an excellent training field for the osseointegrated prosthesis, be it the classic Brånemark (Nobelpharma USA, Chicago, IL) restorative or the implant overdenture concept.

Attachment fixation for overdentures. Part I

Scientific evidence of both constructive and destructive movements of teeth has influenced the design and selection of attachments for overdentures. Dowel designs that would be acceptable for normal copings must be reconsidered in view of the mechanical effectiveness of parallel-walled dowels and screws. Coping designs for attachment overdentures must provide retention, resistance to rotation, and bulk when joined with the dowel and attachment, without negating the advantage of the reduced crown-root ratio. Splinting with a bar-type attachment (1) has advantages over splinting with a stud-type attachment that outweigh the disadvantages of bulk and (2) provides ease of replacement when one of several remaining teeth is excessively mobile. Part II will consider the various types of bar, stud, and auxiliary attachments for the overdenture.