Adhesive attachments for removable partial dentures

Since twenty years adhesive dentistry plays a certain role in the design of removable partial dentures. With the use of adhesive attachments the esthetics and retention of a removable partial denture can be improved. To apply these attachments successfully the contour of a sound abutment has to be corrected by grinding to provide retention and resistance. The procedures for constructing removable partial dentures with adhesive attachments are described. It is recommended to apply adhesive attachments in the general dental practice.     

插销式附着体的临床应用

目的 探讨插销式附着体在双侧远中游离端局部活动义齿中的固位和稳定性。方法 制作带有插销式附着体底座的基底冠,并通过平行研磨仪确定附着体的工仙就位道。结果 以插销式附着体为固位体的双侧远中游离端局部活动义齿的固定和稳定性高于普通三臂卡环为固位体的义齿。结论 插销式附着体是一种结构简单,固位和稳定性较好的固位体。值得临床推广应用。     

Extracoronal resilient attachments in distal-extension removable partial dentures.

Esthetics is often compromised in patients who wear removable partial dentures with metal clasps placed on anterior teeth. Clinical procedures are presented for a new design of a removable partial denture that improves esthetics and function through a new dental attachment. The extracoronal resilient attachment system offers vertical resiliency and universal stress relief for use where a resilient prosthesis is indicated. The removable partial denture retained by these attachments provides esthetics, vertical resiliency, and easy replacement of worn attachments.     

Removable Dental Prosthesis Splint. An Occlusal Device for Nocturnal Bruxing Partial Denture Users

Nocturnal bruxing is a parafunctional activity of the masticatory system that may create problems for removable dental prosthesis (RDP) users. Such problems may include root fractures, increased mobility of abutment teeth, excessive wear of resin denture teeth, minor connector bending, or denture base cracking. This clinical report presents an occlusal device fabricated for an RDP patient. The device used existing ERA attachments for added retention designed with the intended purpose of protecting the definitive fixed and RDP from damage due to nocturnal bruxing activity and providing for even distribution of parafunctional forces.     

A Technique for Retrofitting a Metal Ceramic Crown to an Attachment‐Retained Removable Partial Denture: A Clinical Report

In dental applications, precision attachments have been used to retain removable partial dentures (RPDs) for several decades. Various types of extracoronal attachments are commonly used in combination with fixed partial dentures and RPDs to achieve retention and stability. Fracture of the framework, fracture of the roots or teeth, and irretrievable decrease of retention are common reasons for a failed attachment‐retained RPD. Another complication of metal ceramic crowns with precision attachment is decementation of the crowns. When fixed components of the attachment‐retained RPD fail, the traditional treatment approach requires remaking both the fixed and removable components of the attachment‐retained RPD. This technique describes retrofitting of a metal ceramic crown to a resilient attachment‐retained RPD.     

磁性附着体义齿修复的五年观察及并发症防治

目的:评价磁性附着体义齿修复的长期疗效,探寻其并发症防治策略。方法:对33例共使用61副Magfit磁性附着体行可摘局部义齿修复的患者完成5年随访观察。结果:磁性附着体活动义齿舒适、稳定,长期临床效果满意,但有4副附着体磁体脱落,19颗基牙出现龈缘炎,基牙临床指数除牙龈指数有显著差异外,出血指数、牙周袋指数、松动度均与修复前无明显差异。结论:应用磁性附着体进行活动义齿修复5年观察疗效满意,但磁体粘固方式有待改进。     

Composite resin root coping with a keeper for magnetic attachment for replacing the missing coronal portion of a removable partial denture abutment

Numerous methods for replacing missing removable partial denture abutments have been introduced, however, most of them are time consuming and require several visits to complete the procedure. Since magnetic attachments can provide support and bracing as well as retention for overdenture abutments, the remaining tooth root structure can be used to support the coping with the keeper. Through the use of composite resin and adhesive material, improved retention of the keeper to the root may be achieved, along with improved esthetics. This article describes a method for replacing the missing abutment of a removable partial denture with a magnetic attachment, and a composite resin coping with a keeper.     

Influence of attachment wear on retention of mandibular overdenture

The aims of this study were: (i) to evaluate and compare retention of two-teeth (implant) supported mandibular overdenture with either stud or magnetic attachments during linear (axial) and rotational (paraxial) dislodgements; (ii) to compare retentive properties before and after wear simulation. The test group consisted of five magnetic and four stud overdenture attachments (n = 12 specimens for each attachment type). Retention in axial direction was evaluated on one-tooth (implant) model by measuring maximum retentive force (N) and range of retention (mm) during the linear dislodgement. Retention in the paraxial direction was evaluated on mandibular-overdenture model by measuring the maximum retentive force (N) during three types of rotational dislodgements - anterior, lateral and posterior. The minimum number of cycles required to simulate wear was determined by special wear test. Afterwards, the wear was simulated in the test group, and retention in axial and paraxial directions was measured again. Statistical analysis: one-way anova, Scheffe post hoc and paired-samples t-tests (P < 0.05). Initially, studs had higher retention (4-11 N) than magnets (4.5-6 N) in axial direction. After the wear simulation, it had decreased from 76% to 48% for some of the studs and had become similar to the retention of magnetic attachments. Magnets had lower retention range (0.2-0.3 mm) than studs (0.5-1.1 mm). Studs provided similar or higher retention in paraxial directions than magnetic attachments both before and after wear simulation. Retentive properties of magnets decreased mostly with posterior rotational dislodgement. Retentive properties of stud overdenture attachments were less constant.     

Fabrication of custom clips for bar-and-clip attachments for implant-supported overdentures

Bar-and-clip attachments for dental implants are a common and versatile device for improving the retention and stability of a removable prosthesis. Manufactured clips may be unsubstantial and may not always fit or provide the desired amount of retention for the bar. The purpose of this article is to describe a technique for custom fabrication of clip attachments. The wax pattern of the clips is fabricated and then cast in dental gold alloy. The gold clips are then cut to an appropriate size that will allow for a variety of clinical applications.     

Tooth-supported stud-retained prostheses: three case reports

The use of teeth as overdenture abutments is a common form of treatment. However, most roots are used only fur support. Simple stud precision attachments will also aid the retention of the prosthesis. This article presents three different cases where studs have been used to help retain removable prostheses.     

���в����ν��μ����и���Ӧ�ü���չ

??Different from conventional fixed appliance systems??the orthodontic force of clear removable thermoplastic appliances not only derives from the deformation force of thermoplastic??but also needs attachments to achieve three-dimensional tooth movements. Attachments can be used to enhance the efficiency of tooth movements and make the expected orthodontic goal more easily to achieve. The paper mainly introduces the types??materials and retention of attachments as well as the influence of attachments on the efficiency of tooth movements.     

无托槽隐形矫治技术中附件应用及进展

不同于传统的固定矫治技术,无托槽隐形矫治技术的矫治力不仅来源于热压膜的形变力,而且在牙齿移动的控制方面,需要“附件”的帮助来实现牙齿三维空间的移动。附件的使用不仅可以提高牙齿移动的效率,也让预期矫治目标更易实现。文章主要介绍附件的种类、材料、固位以及附件影响牙齿移动效率的相关研究。     

Resistance to Wear of Four Matrices with Ball Attachments for Implant Overdentures: A Fatigue Study

Purpose: The study evaluated in vitro the retention force and the wear resistance over simulated function of four matrix components of ball attachments for implant‐retained overdentures. Materials and Methods: Four types of matrices for ball attachments were evaluated in a fatigue study simulating 5500 cycles of insertion and removal. The matrices used were (1) a Teflon matrix supported by a metal housing, (2) a titanium matrix, (3) a gold alloy matrix, (4) an O‐ring matrix using the red color ring for medium retention. Dimensional changes of the ball attachments were investigated with a profilometer. Results: The Teflon matrices showed an increase of 27% in retention at 5500 cycles while the gold alloy matrices showed an increase of 50% in retention in the first 500 cycles and remained relatively stable up to 5500 cycles. On the other hand, titanium matrices and O‐ring matrices exhibited progressive loss of retention ending with 68% and 75% of retention loss, respectively, at 5500 cycles. Dimensional analysis by profilometer revealed significant wear on the ball attachment only for titanium matrixes. Conclusions: Gold alloy and Teflon matrices showed the highest retention values without retention loss after 3 years of simulated function. Titanium and O‐ring matrices presented a continuous loss of retention with the highest wear on the ball attachments when combined with the titanium matrix.     

Wear behavior of precision attachments

PURPOSE: The purpose of this article was to compare the wear behavior of precision attachments with plastic inserts to conventional metal-alloy precision attachments. MATERIALS AND METHODS: In a comparative study attachments of various designs were subjected to alternating load cycles in a wear simulator. In addition to conventional adjustable attachments with metal-alloy matrix and patrix elements, attachments with female elements that are lined with plastic inserts were investigated for the first time. In each wear test 10,000 separating and joining movements were performed in an axial direction under a continuous spray of artificial saliva at 37 degrees C. RESULTS: The attachments with metal surfaces showed a rapid loss of approximately 60% of the required separating/joining forces during the first 1,000 cycles; after a further 9,000 cycles these forces fell to 25% and 35%, respectively, of the initial value. The attachments with plastic inserts, by contrast, showed only a 4% and 8% loss, respectively, of the required separating/joining forces even after 10,000 wear cycles. With one attachment type a reproducible 20% increase of retention occurred during the testings. CONCLUSION: The precision attachments with plastic female inserts showed only negligible amounts of wear and the most consistent retentive force in comparison with conventional precision attachments consisting of metal-alloy matrix and patrix components.     

Viability of magnetic denture retainers: a 3-year case report.

The purpose of this article is to report on the use of a neodymium-iron-boron magnet enclosed in a laser-welded stainless steel casing as a viable method of retention for removable partial dentures. This mode of retention dispenses with unsightly clasps, at the same time providing direct tooth support via the overdenture abutment. Magnetic attachments are simpler to incorporate into the prosthesis than mechanical attachments, which require springs, coplanar surfaces, or screws. Overdentures of this nature have the added advantage of being more stable and retentive than conventional partial dentures, and they are easily removed and seated without the patient having to grapple with clasps and complex paths of insertion. This particular magnetic attachment exhibited no deterioration after 3 years in function, and the results so far have been promising.     

Prosthodontic Rehabilitation of an Ectodermal Dysplasia Patient with Implant Telescopic Crown Attachments

Telescopic crown attachments have been successfully used in completely and partially edentulous patients. This type of attachment provides retention, support, and stability with optimal hygiene for the removable dental prosthesis (RDP). With the emergence of CAD/CAM technology, telescopic crown attachments can be virtually designed and milled precisely to ensure a passive fit of the attachment parts and maximal functionality of the RDP. This article reviews both the clinical outcome and prosthodontic rehabilitation of telescopic crown attachments of an edentulous ectodermal dysplasia patient with solitary rigid conical telescopic crown attachments.     

(Semi-)precision attachments for cast metal frame removable partial dentures

When compared to a conventional attachment, a (semi)precision attachment for a cast metal frame removable partial denture can perform a number of functions better. Proper assessment of the condition of the abutment teeth is needed for an adequate indication. Selecting the type of (semi-)precision attachment is primarily determined by the available maxillomandibular space, the crown length as well as the possibility of adequate oral self-care. With regard to technical characteristics, (semi-)precision attachments are classified according to measures of freedom. The distinct types are cast intra- and extra-coronal, adhesive and overdenture (semi-)precision attachments. With the lapse of time, some wear of the different parts of an attachment may occur, requiring specific subsequent care. Whether or not in combination with oral implants, (semi-)precision attachments often offer patients improved self-confidence and self-image. However, the relatively high cost is a barrier to apply (semi-)precision attachments widely.     

附着体固位可摘义齿临床应用

目的：观察不同类型附着体固位可摘义齿的临床效果。方法：采用冠外精密附着体、磁性附着体、套筒冠作为固位装置制作可摘义齿,对游离端缺失下颌义齿和多牙缺失病例32例进行修复。随访6个月～3年,对义齿美观舒适性、固位力、咀嚼功能、摘戴适应情况及基牙松动、义齿下沉加衬情况进行观察。结果：所有病例对义齿美观舒适、固位力、咀嚼功能均感满意。30例对义齿摘戴适应（93．75％）,2例感到义齿摘取不便（按扣式、套筒冠义齿各1例）。结论：附着体固位可摘义齿兼有固定、活动义齿的优点,能达到良好的临床修复效果。     

Parallel bonded cast attachments for removable partial dentures

The original design of a semi-precision extra-coronal attachment for partial dentures is illustrated, and its fabrication in a cast non-precious bondable alloy is described. A step-by-step method is also described of bonding multiple attachments in parallel for the retention and support of removable partial dentures. Clinical cases are illustrated. The results of trials indicate that the method is clinically viable and, in selected cases, appears to offer distinct advantages over existing retention systems.     

Comparison of load transfer by maxillary distal extension removable partial dentures with a spring-loaded plunger attachment and I-bar retainer.

This study photoelastically compared the stress distribution characteristics of two maxillary bilateral distal-extension removable partial denture designs, one using I-bar retention and the other using a semiprecision spring-loaded plunger attachment. Each prosthesis was subjected to vertical and horizontal extension-base loads. Comparisons were made from photographic recordings of isochromatic fringe distributions. The two retention designs produced comparable stresses with splinting of abutments for the plunger attachment. The attachment-retained prosthesis proved less stable with some loadings. Stress patterns followed three trajectories in the maxilla. A basis for stress distribution comparisons to other maxillary removable partial denture attachments is established.