Implant-retained partial overdenture with resilient attachments.

Management of partially edentulous patients can still be a prosthodontic challenge. Replacing the missing teeth with conventional removable partial dentures (RPDs) is the traditional method for the treatment of partial edentulism; however, there are many potential disadvantages associated with traditional RPDs. With the advent of osseointegrated dental implants, possibilities of prosthetic reconstruction for partial edentulism are endless. This article discusses the implant-retained partial overdenture (IRPOD) with resilient attachments as a predictable and cost-effective treatment for partially edentulous patients.     

A systematic approach for removable partial denture design

Implants are becoming increasingly popular as a means of restoring edentulous spaces. However, many patients still cannot afford implants or do not have enough bone to support them. For these patients, removable partial dentures are an option for restoring function to their dentition. This article presents a way of considering removable partial denture design without becoming overwhelmed and frustrated with the process. Retention, support, and stability are discussed.     

Use of dental implants to improve unfavorable removable partial denture design

This study aimed to determine whether the use of a limited number of dental implants, with no rigid connection between implants and teeth and as few as possible prosthetic element requirements, is a viable solution for improving unfavorable removable partial dentures (RPD) design. Fifteen partially edentulous patients with an unfavorable number and distribution of abutment teeth were treated, each with a limited number of implants, from 1997 to 2004, resulting in an improved RPD design. Implant survival rate was 100%, and prosthetic complications were minor. All patients reported great satisfaction with the partial dentures and good chewing efficiency. The results indicate that the use of dental implants to improve unfavorable RPD design is a viable and cost-effective treatment modality.     

Prosthetic rehabilitation of a bone defect with a teeth-implant supported, removable partial denture

The use of teeth-implant, mucosa-supported removable dentures for rehabilitation of partially edentulous patients involves highly complex biomechanical aspects. This type of prosthesis associates 3 kinds of support that react differently to the functional and parafunctional forces developed in the oral cavity. Although the construction of removable partial dentures may seem paradoxical when osseointegrated implants are placed, in some cases, this option is an excellent alternative to solve difficulties related to the anatomic, biologic, psychomotor, and financial conditions of the patient. This article reports on a case in which a teeth-implant, mucosa-supported removable partial denture was the option of choice for a patient with financial and anatomic limitations, having a large structural loss of the residual alveolar ridge caused by trauma by a gunshot injury at the mandible. The 5-year follow-up did not reveal any type of biomechanical or functional problem.     

Oral conditions and aptitude to receive implants in patients with removable partial denture: a cross-sectional study. Part II. Aptitude

summary The aim of this study was to evaluate the possibility of replacing removable partial denture (RPD) with fixed partial dentures on osseointegrated implants in a selective group of patients with partially edentulous lower jaws. Forty patients were evaluated to receive implants. Twenty-three patients showed a precarious oral hygiene, five patients refused the treatment (being satisfied with their RPD), six refused for economic reasons, three patients refused for fear and scepticism, one for long duration of therapy, and one was not treated because of a very marked atrophy of the alveolar crest. Finally, one patient was treated with implants. For these reasons, at the present time implants are not an appropriate treatment for introduction into large-scale public health programmes and RPD must still be considered a valid therapeutic procedure.     

Esthetic considerations in removable prosthodontics

Patients requiring extensive replacement of teeth with removable prostheses are indeed esthetic orphans in many contemporary dental practices. Although the advent of successful osseointegration has dramatically reduced the need for removable prostheses, there are still many patients who for health, anatomic, psychological, or financial reasons are not candidates for implants. These patients deserve the same level of esthetic restorative dentistry as those who are restored with fixed prostheses. Clearly, the restorative dentist has the greatest flexibility from an esthetic standpoint with complete dentures. Soft and hard tissues can be replaced with contemporary characterized denture-base materials, and a truly infinite variety of tooth forms, shades, and arrangements can be used to meet the expectations of the most demanding patient. For partially edentulous patients, the major problem is designing a removable partial denture that avoids the unsightly display associated with conventional clasp assemblies. There are strategies available to accomplish this effectively while establishing an environment for optimal periodontal health, and to minimize destructive stresses on the abutment teeth.
CLINICAL SIGNIFICANCE
This article discusses the procedures essential for providing an upscale, quality esthetic service with removable prostheses. Effective strategies to eliminate unsightly clasp assemblies with removable partial dentures are described.     

老年人可摘局部义齿折裂的设计因素

目的：分析老年人可摘局部义齿折裂的设计因素，旨在提高可摘局部义齿的设计水平和质量。方法：通过对临床上216例老年人可摘局部义齿折裂病例的观察，根据王征寿分类法归纳各类义齿折裂的常见类型，分析其中的薄弱环节和设计因素。结果：一类义齿咬合低时易发牛近远中向折裂；二类义齿咬合紧时常在游离端远中发生近远中向折裂，尤以上颌结节和磨牙后垫部位多见；三类和五类义齿的舌腭侧基托常在两个缺牙区之间尤其是靠近缺牙区的部位发牛与牙弓相交叉的折裂；四类义齿常发牛人工牙脱落或腭侧基托横折；人类义齿舌腭侧基托易发生纵折，折裂线常位于人工牙与基牙交界处。以上可摘局部义齿折裂的发生部有其设计与制作上的原冈，作者对此提出了相应的对策。结论：应特别注重义齿的抗折设计，这是提高可摘局部义齿修复质量的重要环节。     

Occlusal Rehabilitation Using Implants for Orthodontic Anchorage

Osseointegration is defined as a direct interaction of bone to an implant surface. As a result, the implant fixture is immobilized in the bone and lends itself to function as an anchor for orthodontic tooth movements. When properly treatment-planned, these implants can also be used as prosthodontic abutments for single crowns, or removable or fixed partial dentures. This article describes how implant fixtures were surgically placed within the maxillary and mandibular arches of a partially edentulous patient, and used for orthodontic anchorage to reposition the remaining teeth into a more favorable arch position, creating increased posterior interocclusal space. The fixtures were then restored with fixed partial dentures to rehabilitate the patient into a mutually protected occlusion.     

The management of a completely edentulous patient using simultaneous maxillary and mandibular CAD/CAM-guided immediately loaded definitive implant-supported prostheses: a clinical report

Functional rehabilitation of a completely edentulous patient with removable prostheses is a clinical challenge. A patient with an edentulous maxilla and mandible received 6 endosseous implants in the maxilla and 5 implants in the mandible using CAD/CAM surgical templates. Definitive maxillary and mandibular implant-supported fixed complete dentures were connected immediately after implant placement using a CAD/CAM-guided implant surgical placement protocol.     

Detection of improvement in the masticatory function from old to new removable partial dentures using mixing ability test

The aim of this study was to determine the sensitivity of the Mixing Ability Test to detect improvement of masticatory function in subjects on transition from old to new removable partial dentures. Thirty-two subjects (seven males, 25 females, mean age 65.0 years) with distal extension partially edentulous area in mandible and/or maxilla participated in the study. The following reasons were presented for replacing the old removable partial dentures with new ones: fracture and/or poor fitness of retainers, extraction of abutment teeth, poor fitness of denture base, severe wear of artificial teeth and request for metal base dentures. Masticatory function with old and new removable partial dentures after an adaptation period (mean 27.4 weeks) was evaluated by the Mixing Ability Test. Subjects were asked to masticate five two-coloured wax cubes with each removable partial denture. Mixing Ability Index was obtained from the colour mixture and shape of the masticated cubes. Wilcoxon signed-rank test was used to test the difference of Mixing Ability Indexes between old and new removable partial dentures. The mixing ability indexes with new removable partial dentures (mean+/- s.d.: 0.70+/- 0.68) was significantly higher (P<0.001) than those with old removable partial dentures (-0.11+/-1.13). The results suggest that the Mixing Ability Test was capable of detecting improvement in masticatory function with new removable partial dentures.     

An immediately loaded CAD/CAM-guided definitive prosthesis: a clinical report

Dental implants have had a major impact on the treatment of edentulous patients. Fixed complete dentures have allowed removable complete dentures to be replaced with fixed prostheses. A new treatment modality using immediately loaded implants placed with a CAD/CAM surgical template using a flapless surgical technique, then loaded with a prefabricated restorative prosthesis, is presented. This report describes the Teeth-in-an-Hour (Nobel Biocare, Yorba Linda, Calif) treatment provided for a patient.     

Subjective need for implant dentistry in a Swedish population aged 45–69 years

The present paper is part of a comprehensive study of dental conditions and attitudes in a Swedish county population aged 45-69 years. A questionnaire was mailed to 3000 randomly-sampled individuals. The response rate was 79.4%. Part of the questionnaire contained questions about subjective need for implant treatment. The subjects were informed of the clinical procedures as well as of the fees for implant treatment in the Swedish insurance system. The subjects wearing removable dentures were asked if, instead of their removable denture(s), they wanted dental implants if such treatment was possible. Of those wearing removable partial dentures, 23% answered "yes". The corresponding figure for subjects totally edentulous in one jaw was 17%; for subjects totally edentulous in both jaws 8%. The individuals who had reported missing teeth not replaced were asked if they wanted their missing teeth replaced by dental implants if such treatment were possible. The % answering "yes" was 21%. The subjects with all teeth remaining were hypothetically asked what kind of treatment they wanted if they would lose 1 or 2 of their teeth. The answer "dental implant" was given by 51%. Thus, subjective need for dental implants tended to decrease with poorer dental conditions. The major reason for not wanting dental implants was satisfaction with present dental conditions. Cost for treatment had some importance, while environmental and psychological factors showed only very limited influence.     

Veterans Administration Cooperative Dental Implant Study — Comparisons between fixed partial dentures supported by blade-vent implants and removable partial dentures. Part I: Methodology and comparisons between treatment groups at baseline

This study was conducted to determine whether fixed partial dentures supported by dental implants provide an acceptable alternative to conventional removable partial dentures in patients with Kennedy class I or class II edentulous conditions. The acceptability of the new treatment will be based on success rates, impact on the health of the remaining dentition, masticatory performance, patient satisfaction, and maintenance care and cost. The study was planned also to provide comparisons between two designs commonly used by dentists for fabricating removable partial dentures. The designs differed only in terms of the type of the retainer (clasp type) and tooth support (rest location).A total of 272 patients with Kennedy class I and class II edentulous conditions were assigned on a random basis to one of the treatment groups, 134 to receive a removable partial denture and 138 a fixed partial denture supported by a blade-vent implant. All of the patients were medically screened and met prespecified criteria for oral hygiene, bone support for abutment teeth, and size of the residual ridge.Thirty-four patients were eliminated from the study before completion of their treatment. An additional six patients with early implant failures were reentered in the study and followed up as a separate group. The remaining 232 patients received comprehensive dental care, including removable partial dentures for 118 and fixed partial dentures for 114 patients.A series of examinations, radiographs, masticatory performance tests, patient satisfaction, food selection questionnaires, and dietary history were completed before initiation of the treatment, 16 weeks after the insertion of an RPD or an implant, and thereafter at 6-, 18-, 36-, and 60-month intervals. In addition, patients were seen at 6-month intervals for a recall dental examination, oral prophylaxis, plaque instructions, radiographic survey of the implant, and any needed dental treatment.The randomization stratification approach produced two treatment groups with comparable age, number of remaining maxillary and mandibular teeth, type of opposing dentition, and percent of patients with Kennedy class I and class II edentulous conditions. The mean scores of bone support, tooth mobility, and sulcular depths of abutment teeth were also similar. Significant but comparable improvements in oral hygiene and sulcular depth occurred in the two groups after treatment. The periodontal health scores at the 16-week interval serve as the baseline to measure subsequent changes in periodontal health. This prospective longitudinal study with prespecified criteria for implant and removable partial denture failure should provide reliable estimates of failure rates, number and types of complications, maintenance care needs, and total costs for the two treatment modalities and the two RPD designs.     

Microcomputer-aided removable partial denture design: the next evolution

A microcomputer-based program for the design of removable partial dentures has applications in dental education and the clinical practice of dentistry. The program requires a Macintosh computer with a minimum configuration of one megabyte of random access memory and a hard disk drive with a HyperCard program. The instructional design uses an interactive, branching user interface to conduct a search of removable partial design data. The screen design is based on a dental laboratory work authorization, with graphic representations of partially edentulous dental arches and textual information that can be browsed in a nonlinear manner by the user. Approximately 160 removable partial denture designs are provided in the program, as well as the ability to modify the drawings and text to reflect various other clinical situations and to print the work authorization for submission to the dental laboratory.     

ASSESSMENT OF THE PREVALENCE INDEX ON SIGNS OF COMBINATION SYNDROME IN PATIENTS TREATED AT BAURU SCHOOL OF DENTISTRY,UNIVERSITY OF SAO PAULO

A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition.     

Management of the edentulous patient

Being edentulous is a handicap, and the main objective of implant placement is to provide support of fixed prostheses or to stabilize complete dentures in the edentulous jaw. Clinical experience and clinical studies have demonstrated the broad application of non-submerged ITI implants in prosthetic therapy in standard sites and in situations of advanced atrophy or substantial loss of tissue. The ITI implant was developed for universal use in partially and completely edentulous patients and for replacement of single missing teeth. The abutment system offers the choice of both removable and fixed prostheses with identical secondary parts. The present article describes the use of ITI implants for prosthodontic rehabilitation in the completely edentulous jaw. Indications and various types of fixed or removable prostheses, alternatives and variations of design are discussed. Prosthetic design is dependent on the number and location of implants, and conversely, the number of implants that can be placed will determine the choice of prosthesis. Treatment planning in general and with respect to individual anatomic-morphologic conditions is described for the upper and lower jaw. Details of clinical procedures with ITI implants related to the specific design of prostheses are presented. Biomechanical aspects of fixation and stabilization of prostheses and aspects of occlusion to be built up complete the overview.     

The Use of Implants to Improve Removable Partial Denture Function

The oral rehabilitation with conventional removable partial dentures in Kennedy class I patients allows continuous bone resorption, dislodgment of the prosthesis during the mastication caused by the resilience of the mucosa, and rotation of the prosthesis. Thus, the associations of distal implants become an attractive modality of treatment for these patients. This case report presented an association of removable partial dentures, milled crowns and osseointegrated implants to rehabilitate a partial edentulous patient. A removable partial denture associated with implants and metal-ceramic milled crowns can offer excellent esthetics, and will improve function and biomechanics, at a reduced cost.

     

Rotational path removable partial denture (RPD): conservative esthetic treatment option for the edentulous mandibular anterior region: a case report

It can be esthetically and financially daunting for patients to lose teeth in an anterior region of the mouth. For these patients, traditional treatment options presented in the past have included fixed partial denture, implants, and conventional removable partial denture (RPD). For patients faced with financial, anatomical, and/or esthetic limitations, the edentulous region can be restored successfully with a rotational path RPD. Rotational path RPD designs have often been overlooked by the dental profession due to its complex concepts involving the prosthetic design and sensitive laboratory techniques. With better understanding of the concepts and design, the dental clinician can deliver the highest esthetic outcome in compromised areas in which other treatment options may often face limitations. This paper reviews the method used to esthetically design and plan a posterior-anterior rotational path RPD in an edentulous mandibular anterior region for a patient missing the mandibular incisors. CLINICAL SIGNIFICANCE: Due to inadequate understanding of the mechanics of rotational path RPDs, many clinicians have not adapted the application of this advantageous prosthesis. When correctly designed and fabricated, the rotational path RPD provides improved esthetics, cleanliness, and retention for patients who may not be suitable candidates for implants or fixed partial dentures in tooth-supported edentulous regions.     

Qualitative changes in dental plaque formation related to removable partial dentures

A study was performed on the microbial composition of dental plaque developing on fifteen abutment teeth in nine partially edentulous subjects. Bacteria were counted in samples of plaque which had formed on vestibular surfaces, and on proximal surfaces facing edentulous spaces, during a period when dentures were not worn, and then for a period when dentures were being worn. It was found that the presence of removable partial dentures favoured a proliferation of spiral organisms.     

不同设计形式RPD对支持组织应力分布影响的光弹分析

目的:探讨分裂式设计与RPI设计制作的钴铬合金铸造支架RPD修复KennedyⅠ类缺损对支持组织应力分布的影响,为优化义齿设计提供实验依据。方法:分别以分裂式设计和RPI设计两种设计形式的钴铬合金铸造支架RPD修复下颌牙双侧游离缺失,用三维光弹应力冻结切片技术测试义齿加载后对基牙和缺牙区牙槽骨的应力分布,并加以分析比较。结果:钴铬合金分裂式设计的铸造支架RPD承受压力沿基牙牙体长轴传导,基牙远中所受扭力较小。结论:对于KennedyⅠ类牙列缺损,钴铬合金分裂式设计的铸造支架RPD使支持组织受力均匀、合理,减小了基牙受到的扭力,达到基牙保护的目的,是一种值得推广的设计。