Ethics in the provision of removable partial dentures

Aim: To investigate the construction of cobalt-chromium removable partial dentures by commercial private dental laboratories. Methods: Ninety master casts for fabrication of cobalt-chromium removable partial dentures were obtained from three commercial laboratories randomly selected. Casts were assessed for dental arch treated, Kennedy classification, cast surveying, denture design information provided by the dentist, and mouth preparation (rest seat, guiding plane and retentive area). Dental technicians answered a questionnaire regarding qualification of assisted dentists, monthly number of framework castings, and use of dental surveyor. Mouth preparation was compared among laboratories using Kruskal-Wallis test (α=0.05). Results: The percentage of Kennedy class I was 16%, class II 19%, class III 56%, and class IV 9%. The majority of master cats (51%) examined was sent to dental laboratories without any design information and did not comply with ethical guidelines in the provision of RPD. Approximately half of the casts were considered “inappropriate” for guiding planes and retentive areas. One of the laboratories presented all casts “inappropriate” for rest seat distribution (p<0.001). Conclusions: Mouth preparation frequently failed for guiding planes, retentive areas and distribution of rest seats. It is necessary to provide students with adequate clinical experience at the dental school environment, which will actually be carried into the practice of dentistry.

The impact of rehabilitation using removable partial dentures and functionally orientated treatment on oral health-related quality of life: a randomised controlled clinical trial

OBJECTIVES: This study aimed to compare two different tooth replacement strategies for partially dentate older patients; namely functionally orientated treatment according to the principles of the shortened dental arch (SDA) and conventional treatment using removable partial dentures (RPDs) using a randomised controlled clinical trial. The primary outcome measure for this study was impact on oral health-related quality of life (OHRQoL) measured using the short form of the oral health impact profile (OHIP-14).

METHODS: Patients aged 65 years and older were randomly allocated to two different treatment groups: the RPD group and the SDA group. For the RPD group each patient was restored to complete arches with cobalt-chromium RPDs used to replace missing teeth. For the SDA group, patients were restored to a premolar occlusion of 10 occluding pairs of natural and replacement teeth using resin bonded bridgework (RBB). OHRQoL was measured using the OHIP-14 questionnaire administered at baseline, 1 month, 6 months and 12 months after treatment intervention.

RESULTS: In total, 89 patients completed the RCT: 44 from the RPD group and 45 from the SDA group. Analysis using a mixed model of covariance (ANCOVA) illustrated that treatment according to the SDA concept resulted in significantly better mean OHIP-14 scores compared with RPD treatment (p<0.05). This result was replicated in both treatment centres used in the study.

CONCLUSIONS: In terms of impact on OHRQoL, treatment based on the SDA concept achieved significantly better results than that based on RPDs 12 months after treatment intervention (trial registration no. ISRCTN26302774).

CLINICAL SIGNIFICANCE: Functionally orientated treatment delivery resulted in significantly better outcomes compared to removable dentures in terms of impact on OHRQoL.

Comparison of functionally orientated tooth replacement and removable partial dentures on the nutritional status of partially dentate older patients: a randomised controlled clinical trial

OBJECTIVES: The aims of this study were to conduct a randomised controlled clinical trial (RCT) of partially dentate older adults comparing functionally orientated treatment based on the SDA concept with conventional treatment using RPDs to replace missing natural teeth. The two treatment strategies were evaluated according to their impact on nutritional status measured using haematological biomarkers.

METHODS: A randomised controlled clinical trial (RCT) was conducted of partially dentate patients aged 65 years and older (Trial Registration no. ISRCTN26302774). Each patient provided haematological samples which were screened for biochemical markers of nutritional status. Each sample was tested in Cork University Hospital for serum Albumin, serum Cholesterol, Ferritin, Folate, Vitamin B12 and 25-hydroxycholecalciferol (Vitamin D).

RESULTS: A mixed model analysis of covariance (ANCOVA) indicated that for Vitamin B12 (p=0.9392), serum Folate (p=0.5827), Ferritin (p=0.6964), Albumin (p=0.8179), Serum Total Cholesterol (p=0.3670) and Vitamin D (p=0.7666) there were no statistically significant differences recorded between the two treatment groups. According to the mixed model analysis of covariance (ANCOVA) for Vitamin D there was a significant difference between levels recorded at post-operative time points after treatment intervention (p=0.0470). There was an increase of 7% in 25-hydroxycholecalciferol levels recorded at 6 months compared to baseline (p=0.0172). There was no further change in recorded levels at 12 months (p=0.6482) and these increases were similar within the two treatment groups (p>0.05).

CONCLUSIONS: The only measure which illustrated consistent significant improvements in nutritional status for either group were Vitamin D levels. However no significant difference was recorded between the two treatment groups.

CLINICAL SIGNIFICANCE: Functionally orientated prosthodontic rehabilitation for partially dentate older patients was no worse than conventional removable partial dentures in terms of impact on nutritional status.

Prosthodontic rehabilitation of a patient using a swing-lock lower denture after segmental mandibulectomy

A swing-lock denture is useful in partially dentate patients where the configuration of the remaining teeth means that either the retention or stability available for a conventional removable partial denture is compromised. Such removable prostheses can also prove to be extremely useful when providing prosthodontic rehabilitation following surgical resection of oral cancer. A 20 year-old patient was referred to the Restorative Department of Cork University Dental Hospital following segmental mandibulectomy to treat a calicifying epithelial odontogenic tumour (Pindborg Tumour). Initial treatment using a conventional lower partial denture failed. This paper outlines the successfully rehabilitation using a lower Cobalt-Chromium swing-lock partial denture.

Evaluation of Stress Patterns Produced by Implant-Retained Overdentures and Implant-Retained Fixed Partial Denture

The purposes of this study were to photoelastically measure the biomechanical behavior of 4 implants retaining different cantilevered bar mandibular overdenture designs and to compare a fixed partial denture (FPD). A photoelastic model of a human edentulous mandible was fabricated, which contained 4 screw-type implants (3.75 x 10 mm) embedded in the parasymphyseal area. An FPD and 3 overdenture designs with the following attachments were evaluated: 3 plastic Hader clips, 1 Hader clip with 2 posterior resilient cap attachments, and 3 ball/O-ring attachments. Vertical occlusal forces of 100 N were applied between the central incisor and unilaterally to the right and left second premolars and second molars. Stresses that developed in the supporting structure were monitored photoelastically and recorded photographically. The results showed that the anterior loading, the overdenture with 3 plastic Hader clips, displayed the largest stress concentration at the medium implant. With premolar loading, the FPD and overdenture with 3 plastic Hader clips displayed the highest stresses to the ipsilateral terminal implant. With molar loading, the overdenture with 3 ball/O-ring attachments displayed the most uniform stress distribution in the posterior edentulous ridge, with less overloading in the terminal implant. It was concluded that vertical forces applied to the bar-clip overdenture and FPD created immediate stress patterns of greater magnitude and concentration on the ipsilateral implants, whereas the ball/O-ring attachments transferred minimal stress to the implants. The increased cantilever in the FPD caused the highest stresses to the terminal implant.

Overlay removable partial dentures for a patient with ectodermal dysplasia: A clinical report

The orofacial characteristics of ectodermal dysplasia include anodontia or hypodontia, hypoplastic conical teeth, underdevelopment of the alveolar ridges, frontal bossing, a depressed nasal bridge, protuberant lips, and hypotrichosis. Patients with this disease often need complex prosthetic treatment. The options for a definitive treatment plan may include fixed, removable, or implant-supported prostheses, singly or in combination. However, financial constraints and other priorities can prevent patients from choosing the most desirable treatment. This clinical report describes the diagnosis and treatment of ectodermal dysplasia in an 18-year-old man. The treatment included interim removable partial dentures fabricated to establish an acceptable therapeutic occlusal vertical dimension, followed by definitive overlay removable partial dentures and composite restorations.

Patients' expectation and satisfaction with removable dental prosthesis therapy and correlation with patients' evaluation of the dentists

Objective. Considering that patients' satisfaction is one of the most important goals in conducting removable dental prosthesis (RDP) therapy and the fact that there are many factors which influence this parameter, the present study aims to evaluate the expectation before and satisfaction after therapy with RDP in patients who seek such therapy. As a secondary objective, other variables that may be associated with patient satisfaction are also evaluated, such as gender, age, Kennedy's classification of the arch supporting the RDP, the number of RDP adjustments after delivery and patients' evaluation of the dentists' conduct. Materials and methods. A sample of 44 patients who received RDP therapy were assigned visual analog scale scores for their expectation before and satisfaction after therapy regarding chewing, aesthetics, comfort and phonetics. They also completed a questionnaire concerning the dentists' conduct. Results. There was no statistically significant difference among scores concerning different genders, age, number of post-delivery settings and arch involved in the RDP. Regarding patients' evaluation of the dentists' conduct, there was a predominance of positive evaluations, but only different answers to the statement (i.e. 'The dentist I saw thoroughly explained the recommended treatment before it commenced') present statistically significant different scores for chewing (p = 0.040) and phonetics (p = 0.046). Conclusions. The average visual analog scale scores were high for both expectation prior to treatment and satisfaction after treatment; however, the scores for expectations were higher than those for satisfaction. © 2013 Informa Healthcare.

Removable Partial Dentures: Use of Rapid Prototyping

The CAD/CAM technology associated with rapid prototyping (RP) is already widely used in the fabrication of all-ceramic fixed prostheses and in the biomedical area; however, the use of this technology for the manufacture of metal frames for removable dentures is new. This work reports the results of a literature review conducted on the use of CAD/CAM and RP in the manufacture of removable partial dentures.

Aesthetic rehabilitation of oligodontia in primary dentition with adhesive partial denture

The primary teeth are essential for bone development and establishment of the arches on occlusion. Thus, the congenitally absence of teeth may trigger a shift in the balance of the occlusion, promoting disharmony in the structures of the maxilla-mandibular system. However, some interventions are possible to be performed in these cases even in pediatric patients, to redirect growth, preventing growth deviations and reestablishing the aesthetic. The aim of this paper is to report the treatment of a 4-year-old child presenting congenitally absence of mandibular central and lateral incisors and maxilla lateral incisors, which consequently compromises aesthetics, occlusal function, and the development and the functional growth of the bones. The oral rehabilitation was performed with an adhesive partial denture, which was able to restore the aesthetic and the occlusal function, therefore being a viable alternative in the treatment of this patient of little age.

Quality of life and satisfaction of patients wearing implant-supported fixed partial denture: a cross-sectional survey of patients from Aracatuba city, Brazil

ObjectivesThe aim of this study was to evaluate the quality of life and satisfaction of patients wearing implant-supported fixed partial dentures.Materials &methodsA total of 106 patients were selected and submitted to clinical examination and collection of the demographic data for evaluation of the implant-supported fixed dentures conditions. All participants agreed to answer to the Oral Health Impact Profile (OHIP-EDENT) questionnaire and another questionnaire about satisfaction with the implant-supported prostheses. The patients were classified into the following three groups for statistical analysis: patients wearing splinted implant-supported prosthesis (E), patients wearing single implant-supported prosthesis (U), and patients wearing single implant-supported prosthesis associated with splinted prosthesis (E+U). Kruskal-Wallis test was used to compare the answers between the groups, and a logistic regression model was measured to verify the relation between variables of the patients and the questionaries'items.ResultsThere were significant differences among groups (P=0.006) for discomfort during surgery itself of the satisfaction questionnaire. The marital status, groups, and hygiene condition were significant mainly for physical pain item.ConclusionsIt was concluded that the patients presented high level of satisfaction and quality of life for the most of the items evaluated as well as the groups showed similar results.

Prosthetic rehabilitation of a patient after a partial mandibulectomy

The treatment of orofacial tumors may cause facial deformities by losses of structures that affect basic functions, i.e. feeding, speech, and the reduction of patient self-steam. A white male patient was diagnosed with epidermoid cancer on the mandibular alveolar ridge with infiltration staging IV A. The patient was submitted to a mandibulectomy associated with a complete extraction of mandibular teeth. For rehabilitation, a conventional denture for the mandibular arch and a removable partial denture for the maxillary arch were fabricated. A correct occlusal adjustment and a satisfactory amount of alveolar bone was favorable for conventional dentures of the prostheses bases improve their retention and stability. After one year of follow-up, the patient was adapted to the prostheses, satisfied with their retention, and reported an improvement on his feeding. The prosthetic rehabilitation of patients after a partial mandibulectomy is essential for their self-steam. Conventional dentures may have their retention and stability improved if they are well fabricated, recorded and have a balanced occlusion. A correct occlusal adjustment and an adequate retention of the prostheses bases may improve their retention and stability. Patients without xerostomy and with a satisfactory amount of alveolar bone may have a favorable prognosis for conventional dentures.

Design of removable partial dentures: a survey of dental laboratories in Greece

The aim of this study was to compare data on design and fabrication methods of removable partial dentures (RPDs) in two major cities in Greece. A questionnaire was sent to 150 randomly selected dental technicians. The participation rate was 79.3%. The anterior palatal strap, the lingual bar, and the Roach-type clasp arm designs were preferred. Half of the RPDs fabricated were retained using precision attachments. Differences between the two cities were observed in types of major maxillary connectors used, types of attachments and impression materials used, as well as the design of distal-extension RPDs. Postdoctoral education was found to have an impact on RPD fabrication. Despite the differences observed, design and fabrication of RPDs followed commonly used principles.

[Zirconia and removable partial dentures]

The present paper deals with the double crown technique in removable prosthodontics. New ceramic materials like zirconia are increasingly used in combination with CAD/CAM technologies for framework fabrication of fixed prosthesis, tooth- or implant-supported. However, zirconia is also a newly accepted material in removable prosthodontics. It replaces gold alloys for the fabrication of primary telescopic crowns. The Galvanoforming technology is preferably used to fabricate the secondary crowns. The combination of both techniques and materials results in a prosthetic reconstruction of high quality, optimum fit and good biocompatibility.