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Partial Dentures (partial + denture)
Kinds of Partial Dentures Selected AbstractsProvisional Prosthetic Management of Mobile Teeth in Conjunction with a Removable Partial Denture Using Orthodontic WireJOURNAL OF PROSTHODONTICS, Issue 7 2009Won-suk Oh DDS Abstract Precision attachment-retained removable partial dentures eliminate the use of visible clasps and improve the esthetic appearance of the smile; however, terminal abutment teeth may be subject to unfavorable stresses under function when misused. A provisional prosthetic management technique that incorporates an orthodontic wire to assist cross-arch support and stability of the periodontally weakened abutment teeth is described. This technique is simple, reversible, does not alter the esthetic appearance of the smile, and controls the mobility of the abutment teeth until a definitive treatment plan is established. [source] Influence of Matrix Type on Surface Roughness of Three Resins for Provisional Crowns and Fixed Partial DenturesJOURNAL OF PROSTHODONTICS, Issue 2 2009Raul Ayuso-Montero DDS Abstract Purpose: This study evaluated the effect of matrix type on the surface roughness of resins for provisional crowns and fixed partial dentures. Materials and Methods: Ninety specimens of two acrylic resins (Trim II, Tab2000) and one bis-acryl composite (Protemp II Garant) were fabricated using one of three matrices: irreversible hydrocolloid (Cavex CA37), poly(vinyl siloxane) (Aquasil) or vacuum-formed matrix (Bio-flow Hard). The sample size for each resin-matrix combination was 10. The vestibular face of one natural maxillary central incisor was used as a model to fabricate all the specimens, following the custom fabrication technique. The average roughness measurements, Ra (,m), were obtained using a profilometer, and the data were analyzed using Kruskal-Wallis and Mann-Whitney U- tests. The results were contrasted against the surface roughness of the tooth using a one-sample t- test. Results: Aquasil and vacuum-formed matrix had a smoother surface than Cavex CA37 regardless of the resin tested (p < 0.05). Protemp II Garant had the smoothest surface regardless of the matrix used, with no significant differences when polymerized against the three different matrices. Trim II polymerized against Cavex CA37 had a rougher (p < 0.05) surface than Aquasil or vacuum-formed matrix. Tab2000 had the smoothest surface (p < 0.05) when polymerized against a vacuum-formed matrix. Conclusions: There is no universal matrix that produces the smoothest surface: this depends on the compatibility between the resin and the matrix. Protemp II Garant polymerized against Cavex CA37 matrix yields a surface that is smooth enough not to require polishing unless this surface is adjusted. [source] Fracture Resistance of Fiber-Reinforced PMMA Interim Fixed Partial DenturesJOURNAL OF PROSTHODONTICS, Issue 4 2006Tamer A. Hamza BDS Purpose: To compare different fiber reinforcements on fracture toughness of interim polymethyl methacrylate materials and then use the best combination to determine the optimal position for fiber placement in an interim 3-unit fixed partial denture (FPD). Materials and Methods: In the first stage of the study, five groups of notched fracture toughness specimens were fabricated and loaded to failure (Instron): (1) unreinforced (control); (2) reinforced with pre-impregnated silanized E-glass fibers (Fibrestick); (3) cold plasma-treated woven polyethylene fibers (Ribbond triaxial); (4) pre-impregnated silanized plasma-treated woven polyethylene fibers (Construct); and (5) 1.0-mm-diameter stainless steel wire. In the second stage, the optimal position (occlusal, middle, or cervical third of pontic) for reinforcement with glass fibers (regimen 2) was tested by loading a 3-unit FPD to failure. All groups were compared with analysis of variance (, < 0.05). Results: The fracture toughness (in MPam1/2) for each reinforced group (Fibrestick 2.74 ± 0.12, Construct fibers 2.59 ± 0.28, Ribbond triaxial 2.13 ± 0.20, and orthodontic wire 1.66 ± 0.09) was statistically greater (p< 0.05) than for the unreinforced group (control = 1.25 ± 0.006). Fracture loads for FPDs were greatest when the fiber reinforcements were placed in the cervical third (cervical = 1165 N). Conclusions: The use of fiber and, to a lesser extent, orthodontic wire is an effective method to reinforce interim restoration resins. [source] Communication Between the Dental Laboratory Technician and Dentist: Work Authorization for Fixed Partial DenturesJOURNAL OF PROSTHODONTICS, Issue 2 2006Zahra Afsharzand DMD Purpose: A questionnaire was sent to laboratory technicians to determine the level of communication between dentists and dental laboratories in specific areas of the work authorization forms for the fabrication of fixed partial dentures. Materials and Methods: A select number of dental laboratories were randomly chosen from the National Association of Dental Laboratories (NADL) for each of the 50 states. The questionnaire was mailed to the laboratory directors for a total of 199 dental laboratories. The survey asked questions pertaining to the following areas of work authorization: legibility and thoroughness of prescriptions, patient information, choice of materials for the prosthesis, design of the prosthesis, and shade description. For each question, the number of responses received was tabulated and converted to a percentage. Results: Of the 199 laboratories surveyed, 114 (57%) responded to the questionnaire. Results from this survey suggest that there is lack of communication between dentists and dental laboratories through work authorization forms regarding choice of metal alloy, type of porcelain to be used, and choice of margin and pontic design for the prosthesis. Conclusions: Information obtained from the responding laboratories included effectiveness of work authorization forms. There were some similar trends indicated by the large percentage of dental laboratories agreeing on lack of communication by the dentists as reflected by the work authorization forms. [source] Patients' experiences with partial dentures: a qualitative studyGERODONTOLOGY, Issue 4 2005Patricia A. Smith Objective:, The aim of the study was to gain insight into people's experiences of being given and using partial dentures. Methods:, In-depth semi-structured interviews were carried out with 23 people of varied age, social background and denture wearing experience in Tayside, Scotland. Participants were encouraged to discuss how they came to have partial dentures, their day-to-day denture use and their interactions with dentists. The interview data were systematically coded using key theme headings, and summary charts were constructed to facilitate analysis. Results:, The initial decision that a partial denture was needed was generally difficult to accept. People perceived the main benefits of partial dentures to be improved appearance and confidence, but experienced a variety of difficulties with their dentures and often coped with these by only wearing them on social occasions. Participants had not always told their dentists about the difficulties they experienced. Barriers to seeking help with denture problems included financial constraints, previous experience of rushed appointments or poor communication from dentists and a perceived lack of entitlement to help when partial dentures were issued free. Conclusions:, Partial dentures can be difficult to cope with. People experience a range of difficulties in wearing them, not all of which have been discussed with dentists. Informative and supportive communication when partial dentures are first needed, and subsequently, can improve the quality of patients' experiences and may help promote effective use and appropriate help-seeking by partial denture wearers. [source] Severe periodontal damage by an ultrasonic endodontic device: a case reportDENTAL TRAUMATOLOGY, Issue 2 2007John D. Walters Abstract,,, Heat produced within a root canal during use of an ultrasonic instrument can be conducted through the dentin into periodontal ligament, bone and soft tissue. If severe in intensity or long in duration, it can induce damage to these tissues. This report describes a case in which an ultrasonic endodontic instrument apparently induced severe damage to alveolar bone, gingiva and nasal mucosa in a 42-year-old female. Overheating of a maxillary central incisor caused necrosis of soft tissue and bone on the facial and mesial aspects and triggered a protracted inflammatory response in the adjacent nasal cavity. To relieve the severe discomfort associated with this damage, the patient chose to have her maxillary incisors extracted and replaced by a removable partial denture. A defect in the soft tissue and bone was present at a follow-up visit 10 months after the extractions. While morbidity of this nature is rare, this case reinforces the need to maintain adequate cooling of ultrasonic instruments. [source] Patients' experiences with partial dentures: a qualitative studyGERODONTOLOGY, Issue 4 2005Patricia A. Smith Objective:, The aim of the study was to gain insight into people's experiences of being given and using partial dentures. Methods:, In-depth semi-structured interviews were carried out with 23 people of varied age, social background and denture wearing experience in Tayside, Scotland. Participants were encouraged to discuss how they came to have partial dentures, their day-to-day denture use and their interactions with dentists. The interview data were systematically coded using key theme headings, and summary charts were constructed to facilitate analysis. Results:, The initial decision that a partial denture was needed was generally difficult to accept. People perceived the main benefits of partial dentures to be improved appearance and confidence, but experienced a variety of difficulties with their dentures and often coped with these by only wearing them on social occasions. Participants had not always told their dentists about the difficulties they experienced. Barriers to seeking help with denture problems included financial constraints, previous experience of rushed appointments or poor communication from dentists and a perceived lack of entitlement to help when partial dentures were issued free. Conclusions:, Partial dentures can be difficult to cope with. People experience a range of difficulties in wearing them, not all of which have been discussed with dentists. Informative and supportive communication when partial dentures are first needed, and subsequently, can improve the quality of patients' experiences and may help promote effective use and appropriate help-seeking by partial denture wearers. [source] Effect of direct retainer and major connector designs on RPD and abutment tooth movement dynamicsJOURNAL OF ORAL REHABILITATION, Issue 11 2008H. ITOH Summary, Designs of removable partial dentures are suggested to affect the mobility of abutment teeth and removable partial denture (RPD) during oral functions. This study aimed to examine the effect of direct retainer and major connector designs on RPD dynamics under simulated loading. Six different Kennedy class II maxillary RPDs were fabricated on a maxillary model. These dentures involved 3 different direct retainers (wrought-wire clasp, RPA clasp, and conical crown telescopic retainer) and 2 different major connectors (Co-Cr major connector and heat-cured acrylic resin with a metal strengthener). Using an experimental model with simulated periodontal ligaments and mucosa that were fabricated using silicone impression material, three-dimensional displacements of the RPDs were measured under a simulated 30-N loading with a displacement transducer type M-3. Significant effects of "direct retainer design" on bucco-palatal displacements and "major connector" on mesio-distal displacements were revealed by 2 × 3 two-way analysis of variance of abutment teeth movements (P < 0·001 and P = 0·002, respectively). Additionally, analysis of variance of RPD displacements revealed significant effects of "direct retainer design" on corono-apical displacements and "major connector" on mesio-distal displacements (P = 0·001 and P = 0·028, respectively). Rigid direct retainers and rigid major connectors decrease the movements of both abutment tooth and RPD. [source] Detection of improvement in the masticatory function from old to new removable partial dentures using mixing ability testJOURNAL OF ORAL REHABILITATION, Issue 9 2005A. ASAKAWA summary, 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. [source] The effect of retainer thickness on posterior resin-banded prostheses: a finite element studyJOURNAL OF ORAL REHABILITATION, Issue 11 2004T.-S. Lin summary, According to its design concept, a resin-bonded prosthesis, compared with the conventional fixed partial denture, is a weak and unstable structure. Therefore, a resin-bonded prosthesis induces a higher failure rate, especially in the posterior region. Recently, adhesion agents have been profoundly improved. However, the design guidelines of posterior resin-bonded prostheses (RBP) have seldom been evaluated from a biomechanical perspective. The objective of this study was to investigate the biomechanical effects of the retainer thickness on posterior RBP using the finite element method. A solid model of a posterior mandibular resin-bonded prosthesis, which employed the second molar and second premolar as the abutment teeth, was constructed and meshed with various retainer thickness (ranging from 0·2 to 1·0 mm). Horizontal and vertical loadings of 200 N were applied respectively at the central fossa of the pontic to examine the stress level at the interface between the retainer and abutment teeth. All exterior nodes in the root, below the cementoenamel junction were fixed as the boundary condition. The results showed that horizontal loading would induce higher interfacial stresses than the vertical loading which indicated that the horizontal component of the occlusal force plays a more important role in evaluating the debonding phenomenon. Further, the peak interfacial stresses increased as the retainer thickness decreased and, based on the fitted relation between retainer thickness and interfacial stresses, a 0·4 mm retainer thickness was suggested as the minimum required to prevent severe interfacial stresses increasing. [source] A retrospective study of pre-fabricated carbon fibre root canal postsJOURNAL OF ORAL REHABILITATION, Issue 10 2003S.-O. Hedlund summary, Although pre-fabricated carbon fibre posts have been used during the past decade clinical evaluations of the technique are still few. Using dental records and radiographs the clinical performance of 65 pre-fabricated carbon fibre posts (Composipost and Endopost) placed in 48 patients who regularly visited a general practice were evaluated in the present study. After an average time of 2.3 ± 0·8 years (median 2·1 years, range 1,4·9 years) of clinical service the failure rate was 3%. Failure occurred in one tooth with a single crown restoration and in one tooth that was part of a cantilever fixed partial denture. Although the failure rate is lower than those mostly reported for metallic posts and cores more clinical studies are necessary to assess the suitability of pre-fabricated carbon fibre posts for routine use as an alternative to individually cast posts. [source] Effect of simulated resin-bonded fixed partial denture clinical conditions on resin cement mechanical propertiesJOURNAL OF ORAL REHABILITATION, Issue 8 2003M. P. Walker summary The purpose of this study was to determine changes in flexural properties of resin cement under simulated resin-bonded fixed partial denture (RBFPD) clinical conditions using aqueous ageing and cyclic loading. Panavia F flexural modulus and strength were measured by static loading to failure after 48-h and 60-day aqueous ageing at 37 °C with and without simulated cyclic occlusal loading. Panavia F sorption and solubility were also measured. Scanning electron microscopy (SEM) was used to characterize the morphology of the fractured surfaces. A two-factor anova (P , 0·05) indicated that cyclic loading produced a significant increase in the flexural modulus with no significant effect on the flexural strength. Conversely, aqueous ageing time produced a significant decrease in flexural strength with no effect on the flexural modulus. The SEM fracture analysis indicated that resin matrix fracture occurred in static-aqueous specimens; while in the aqueous-cycled specimens, resin matrix fracture occurred in addition to an increasing proportion of filler/resin interface fracture. Collectively, these outcomes suggest that initial degradation under simulated resin cement clinical function may be related to breakdown of the filler/resin interface bond, which could contribute to in vivo RBFPD resin cement cohesive failure. [source] A survey of treatment outcomes with removable partial denturesJOURNAL OF ORAL REHABILITATION, Issue 8 2003D. Knezovi, Zlatari summary The patient's satisfaction with removable partial denture (RPD) therapy has become an increasingly important factor in prosthetic treatment. This study examined patients' satisfaction with RPDs in relation to some socio-economic variables, patients' habits of wearing and cleaning RPDs, comfort of wearing RPDs and different RPDs characteristics. A questionnaire was devised for the purpose. Two hundred and five patients were required to assess satisfaction with RPDs. They graded RPDs, depending on the level of satisfaction, on scale ranging from 1 to 5. A dentist determined Kennedy classification, material and denture support, denture base shape, number of missing teeth and evaluated denture construction. Majority of the patients were satisfied with the prosthesis. The patients of a higher education level gave lower grades (P < 0·05) to aesthetics of maxillary RPDs. Almost half of the patients were wearing RPDs during the day. Most of the patients cleaned RPDs three times a day. A significant difference was found between the patients' grades for comfort of wearing mandibular RPDs and number of missing teeth and between hygiene of mandibular RPDs and habits of cleaning them. Majority of the patients treated with RPDs were satisfied with the prosthesis. Dissatisfaction was related to mastication, esthetics, number of missing teeth and maintenance of oral hygiene. [source] Treatment with removable partial dentures: a longitudinal study.JOURNAL OF ORAL REHABILITATION, Issue 5 2003Part II summary The aim of this study was to evaluate the effectiveness of an oral rehabilitation by removable partial denture (RPD). Between 1983 and 1994, 629 patients were provided with an RPD at the Dental School of the Université catholique de Louvain. All the RPDs were constructed with a cobalt,chromium framework. All the treatments were provided by dental students under the supervision of clinical instructors. At recall time (1998,2000), 269 patients could not be reached neither by telephone nor by mail and 27 had died. Consequently, 333 patients were called for clinical examination and 254 of these (76·3%) actually attended. For a total of 292 RPDs checked 1893 persistent teeth were listed, with 804 serving as abutments; more than half (57·6%) of these were crowned, for which 51 debondings were recorded. For the period of observation we listed 79 abutments lost (37 at the upper jaw and 42 at the lower jaw), i.e. 9·8% of the total number of abutments. No relation could be established between the type of the abutments (natural or crowned teeth) and the losses observed (Test of Mantel-Haenszel: P=0·9496). In the upper jaw, the percentage of abutments lost was significantly higher in the presence of free-end edentulous areas as compared with bounded edentulous areas (Test of Mantel-Haenszel: P=0·0002); this difference does not appear for the lower jaws (P=0·9558). If we deduct the 25 abutments related with the 11 non-worn RPDs and the 79 abutments lost, no change becomes apparent for 92·2% of the maxillary abutments and for 85·8% of the mandibular abutments. For the 1089 other teeth, we observed the loss of 40 teeth and the appearance of caries or new fillings for 95 teeth. The fractures of cast clasps represent 3·4%. [source] Influence of working side contacts on masticatory function for mandibular distal extension removable partial denturesJOURNAL OF ORAL REHABILITATION, Issue 3 2003S. Sueda summary The aim of this study was to clarify the influence of working side contacts for masticatory function for a distal extension removable partial denture. Five subjects who had edentulous arches from second premolar to second molar opposing natural teeth participated. Working side contacts were altered by using three types of artificial teeth attached to the denture base. A-form teeth made contact with opposite teeth while acting as the working side in a lateral excursion. The cusp angles of B- and C-form teeth were decreased by 10° and 20°, respectively compared with A-form teeth. B-and C-form teeth discluded with opposite teeth on the working side. Subjects were asked to perform two kinds of masticatory performance test. Obtained data were evaluated by the repeated-measures anova and the Tukey test for multiple comparisons. Results revealed that there was a significant difference (P=0·001) in the three types of teeth in the mixing ability test and the value of A-form teeth was statistically less value than those of the other teeth. However, there was no significant difference in the comminuting ability test. These results suggested that working side contacts between artificial teeth and opposite natural teeth influenced mixing ability, but not comminuting ability. [source] Intraoral Registration Coping Formation Using an Interim Restoration as a MatrixJOURNAL OF PROSTHODONTICS, Issue 5 2010Kostas Stamoulis DDS Abstract An intraoral procedure for registration coping fabrication is described. The indirectly constructed shell of the interim fixed partial denture is used as a matrix, and a light-cured resin is added directly to form the copings. The proposed technique reduces the total number of clinical sessions and can be useful in cases when tooth preparations and final impressions can be completed at the same appointment. [source] ICK Classification System for Partially Edentulous ArchesJOURNAL OF PROSTHODONTICS, Issue 6 2008Sulieman S. Al-Johany BDS Abstract Several methods of classification of partially edentulous arches have been proposed and are in use. The most familiar classifications are those originally proposed by Kennedy, Cummer, and Bailyn. None of these classification systems include implants, simply because most of them were proposed before implants became widely accepted. At this time, there is no classification system for partially edentulous arches incorporating implants placed or to be placed in the edentulous spaces for a removable partial denture (RPD). This article proposes a simple classification system for partially edentulous arches with implants based on the Kennedy classification system, with modification, to be used for RPDs. It incorporates the number and positions of implants placed or to be placed in the edentulous areas. A different name, Implant-Corrected Kennedy (ICK) Classification System, is given to the new classification system to be differentiated from other partially edentulous arch classification systems. [source] Resin-Bonded Overcasting to Salvage a Long-Span Fixed Prosthesis: A Clinical ReportJOURNAL OF PROSTHODONTICS, Issue 5 2008Hiroshi Shimizu DDS Abstract To salvage a failing long-span fixed partial denture (FPD), a resin-bonded overcasting made of a silver-palladium-copper-gold alloy was fabricated and cemented using an adhesive metal conditioner and adhesive resin luting agent to an existing multiple-abutment FPD. [source] Fracture Resistance of Fiber-Reinforced PMMA Interim Fixed Partial DenturesJOURNAL OF PROSTHODONTICS, Issue 4 2006Tamer A. Hamza BDS Purpose: To compare different fiber reinforcements on fracture toughness of interim polymethyl methacrylate materials and then use the best combination to determine the optimal position for fiber placement in an interim 3-unit fixed partial denture (FPD). Materials and Methods: In the first stage of the study, five groups of notched fracture toughness specimens were fabricated and loaded to failure (Instron): (1) unreinforced (control); (2) reinforced with pre-impregnated silanized E-glass fibers (Fibrestick); (3) cold plasma-treated woven polyethylene fibers (Ribbond triaxial); (4) pre-impregnated silanized plasma-treated woven polyethylene fibers (Construct); and (5) 1.0-mm-diameter stainless steel wire. In the second stage, the optimal position (occlusal, middle, or cervical third of pontic) for reinforcement with glass fibers (regimen 2) was tested by loading a 3-unit FPD to failure. All groups were compared with analysis of variance (, < 0.05). Results: The fracture toughness (in MPam1/2) for each reinforced group (Fibrestick 2.74 ± 0.12, Construct fibers 2.59 ± 0.28, Ribbond triaxial 2.13 ± 0.20, and orthodontic wire 1.66 ± 0.09) was statistically greater (p< 0.05) than for the unreinforced group (control = 1.25 ± 0.006). Fracture loads for FPDs were greatest when the fiber reinforcements were placed in the cervical third (cervical = 1165 N). Conclusions: The use of fiber and, to a lesser extent, orthodontic wire is an effective method to reinforce interim restoration resins. [source] A provisional fixed partial denture that simulates gingival tissue at the pontic-site defectJOURNAL OF PROSTHODONTICS, Issue 1 2002Reem Haj-Ali BDS A technique is presented for the fabrication of an esthetic, provisional fixed partial denture that compensates for a pontic-site ridge defect. This provisional restoration enables both the dentist and the patient to evaluate whether this prosthetic approach will adequately camouflage the pontic-site defect or whether surgical correction of the pontic site should also be considered. [source] Differential diagnosis of denture-induced stomatitis, Candida, and their variations in patients using complete denture: a clinical and mycological studyMYCOSES, Issue 3 2009Saadettin Da, istan Summary Denture-induced stomatitis usually occurs in persons who wear a complete or a partial denture. Among the many aetiological and predisposing factors, Candida spp. are believed to play an important role in the initiation and progression of the infection. Seventy cases who attended the clinics of the Dental Faculty, University of Atatürk, Turkey were investigated from the viewpoint of denture-induced stomatitis. After questioning the patients for their personal information, they were examined clinically and smears were obtained from lesions of the palatal mucosa and the contiguous denture surface by calcium aliginate swabs, and inoculated onto Sabouraud dextrose agar supplemented with 1% chloramphenicol, and CHROMagar Candida. Individual yeast species were identified by a germ tube test, development of blastospores, chlamydospores and pseudohyphae and assimilation tests employing the commercial kit API 20C AUX system. According to the results obtained, 70% of the cases had denture-induced stomatitis, and in 68% of them mycological culture results were positive. Candida albicans was the most frequently isolated fungus (68.75%). On the other hand, fungal growth was much more pronounced in the cultures made from the inner surface of the dentures. In conclusion, this study showed that candidal infections are not the predisposing factor in the occurrence of denture-induced stomatitis, but they play a major role, as also some other factors, especially those related with dentures. [source] The all-ceramic, inlay supported fixed partial denture.AUSTRALIAN DENTAL JOURNAL, Issue 2 2010Part 1. Abstract The effect of cavity design is a controversial and underrated factor in the clinical success of ceramic inlays and inlay supported prosthesis. Many articles and studies have been conducted into the advantages and disadvantages of isolated aspects of preparation design, but lacking is a review of the most relevant papers which bring together a consensus on all the critical features. Hence, a review and analysis of cavity depth, width, preparation taper and internal line angles is warranted in our attempts to formulate preparation guidelines that will lead to clinically successful, all-ceramic inlay restorations and ceramic inlay supported prosthesis. [source] Load transfer characteristics of unilateral distal extension removable partial dentures with polyacetal resin supporting componentsAUSTRALIAN DENTAL JOURNAL, Issue 1 2009T Jiao Abstract Background:, To photoelastically examine load transfer by unilateral distal extension removable partial dentures with supporting and retentive components made of the lower stiffness polyacetal resins. Methods:, A mandibular photoelastic model, with edentulous space distal to the right second premolar and missing the left first molar, was constructed to determine the load transmission characteristics of a unilateral distal extension base removable partial denture. Individual simulants were used for tooth structure, periodontal ligament, and alveolar bone. Three designs were fabricated: a major connector and clasps made from polyacetal resin, a metal framework as the major connector with polyacetal resin clasp and denture base, and a traditional metal framework I-bar removable partial denture. Simulated posterior bilateral and unilateral occlusal loads were applied to the removable partial dentures. Results:, Under bilateral and left side unilateral loading, the highest stress was observed adjacent to the left side posterior teeth with the polyacetal removable partial denture. The lowest stress was seen with the traditional metal framework. Unilateral loads on the right edentulous region produced similar distributed stress under the denture base with all three designs but a somewhat higher intensity with the polyacetal framework. Conclusions:, The polyacetal resin removable partial denture concentrated the highest stresses to the abutment and the bone. The traditional metal framework I-bar removable partial denture most equitably distributed force. The hybrid design that combined a metal framework and polyacetal clasp and denture base may be a viable alternative when aesthetics are of primary concern. [source] Orthodontic and prosthetic rehabilitation of unilateral free-end edentulous spaceAUSTRALIAN DENTAL JOURNAL, Issue 4 2006SG Arslan Abstract Most patients prefer fixed dentures, even in the presence of uni and bilateral free-end saddle. The most suitable treatment for this is an implant or implant-supported prosthetic restoration. A combined prosthetic and orthodontic treatment with distalization of a posterior tooth towards the edentulous region is an alternative approach. This study involved a 34.3 year old female patient who had a free-end edentulous space on the left mandibula and missing 1st and 3rd molars on the right mandibula. The patient was offered both a removable partial denture and implant treatment options. A detailed explanation of her situation and suitable treatments were given but she refused both options. Therefore, an alternative combined treatment involving prosthodontic and orthodontic disciplines was performed. The second premolar tooth was distalized orthodontically and used as a distal bridge abutment. After 65 months, prosthetic restoration was functional and abutment teeth and periodontium were pathology free, and the patient was satisfied with the results. [source] Tooth extraction decision model in periodontitis patientsCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2010A. Popelut Abstract Objective: The purpose of this study was to build, around several types of input data, a decision analysis model for dental extraction strategy in periodontitis patients. Materials and methods: The decision analysis was based on the following scenario: a fictitious adult chronic periodontitis patient with no chief complaint, being referred to make a decision of extraction on one single tooth presenting a periodontal defect that may affect the decision-making process. A decision tree was used to identify the treatment options within the next 5 years. Scientific evidences were based on probabilities given by a literature analysis using a systematic approach. Clinical expertize was based on subjective utilities (SUs) assigned by an experts' panel. Expected utilities (EUs) were used to rank the following options: no treatment (EU1) or periodontal treatment (EU2); extraction followed by a tooth-supported fixed partial denture , FPD , (EU3) or an implant-supported single crown , ISC , (EU4). Results: The robustness analysis calculation indicates that the probability of tooth survival needed to be equal to 0.78 in order that the passive option becomes optimal. However, EU1 was impossible to calculate due to the lack of available probabilities. The EU intervals were 79,96, 86,89 and 94,95 for EU2, EU3 and EU4, respectively. Consequently, the FPD option is dominated by the ISC option, and it is not possible to conclude to a difference between the periodontal and the ISC therapy. Conclusions: Within the limits of this model, tooth extraction followed by FPD is the worst strategy compared with ISC or periodontal therapies. To cite this article: Popelut A, Rousval B, Fromentin O, Feghali M, Mora F, Bouchard P. Tooth extraction decision model in periodontitis patients. Clin Oral Impl Res. 21, 2010; 80,89. [source] Corrosion of some selected ceramic alloys used in fixed partial dentures and their postsolder joints in a synthetic neutral salivaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2009Pascal De March The electrochemical behavior of several alloys used in the frameworks of fixed partial dentures and their corresponding postsolders was studied in artificial saliva as a function of chemical composition. Open circuit potentials and polarization resistances were measured. The general electrochemical behaviors between the cathodic domain and the oxidation of solvent were characterized using cyclic polarization. The possible galvanic corrosion of coupled parent and postsolder alloys was also studied. The polarization resistances were high or very high. During immersion, the noblest alloys stayed in the immunity domains of their base elements, whereas Ni,Cr alloys were quickly passivated. The oxidation of the noble elements occurred only when the alloys were exposed to very high potentials solely achievable by artificial means. However, problems of galvanic corrosion may occur between an alloy and its postsolder joint if they are both exposed to saliva. Such corrosion may lead to a weakening of the framework. The parent alloy was often potentially affected by such corrosion but with low exchange currents. [source] Load-bearing capacity of all-ceramic three-unit fixed partial dentures with different computer-aided design (CAD)/computer-aided manufacturing (CAM) fabricated framework materialsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2008Florian Beuer The purpose of this in vitro study was to compare the load-bearing capacity of posterior three-unit fixed dental prostheses (FDP) produced with three different all-ceramic framework materials: glass-infiltrated alumina (ICA), glass-infiltrated alumina strengthened with zirconia (ICZ), and yttria-stabilized polycrystalline zirconia (YZ). Additionally, the influence on aging of mechanical cyclic fatigue loading and thermal cycling in water were evaluated. A total of 20 frameworks each were fabricated from ICA, ICZ, and YZ by a computer-aided design (CAD)/computer-aided manufacturing (CAM) system. The framework designs were identical for all specimens. All frameworks were veneered with porcelain and cemented with glass,ionomer. Prior to fracture testing, 10 FDP of each experimental group were subjected to thermal and mechanical cycling. Additionally, fractographic analysis was performed. Statistical analysis showed that FDP made from YZ had significantly higher load to failure, whereas no difference was found between the other two materials. Aging did not have a significant effect on the fracture load. [source] Load-bearing capacity of all-ceramic posterior four-unit fixed partial dentures with different zirconia frameworksEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2007Philipp Kohorst The aim of this in vitro study was to compare the load-bearing capacity of posterior four-unit fixed partial dentures (FPDs) produced with two different yttria-stabilized polycrystalline tetragonal zirconia (Y-TZP) ceramics, one being a presintered material, the other a fully sintered, hot isostatically pressed material. Additionally, as a novel approach, the influence of preliminary mechanical damage upon the fracture force of an FPD has been investigated. A total of 20 frameworks each were milled from presintered zirconia and from fully sintered zirconia. Prior to veneering, 10 frameworks of each material were ,damaged' by a defined saw cut similar to an accidental flaw generated during shape cutting. Before fracture testing, all FPDs were subjected to thermal and mechanical cycling. Additionally, scanning electron microscopy was used to investigate fracture surfaces. Statistical analysis showed that FPDs milled from fully sintered zirconia had a significantly higher fracture resistance compared with specimens made from presintered material, whereas preliminary damage did not have a significant effect. After aging, FPDs made from both materials were capable of withstanding occlusal forces reported in the literature. Therefore, both types of Y-TZP may be suitable for posterior four-unit all-ceramic FPDs, although further prolonged aging experiments and prospective clinical trials are required to prove their fitness for clinical use. [source] Clinical fit of all-ceramic three-unit fixed partial dentures, generated with three different CAD/CAM systemsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2005Sven Reich In this study, the hypothesis was tested that the marginal and internal fit of CAD/CAM fabricated all-ceramic three-unit fixed partial dentures (FPDs) can be as good as in metal,ceramic FPDs. Twenty-four all-ceramic FPDs were fabricated and randomly subdivided into three equally sized groups. Eight frameworks were fabricated using the Digident CAD/CAM system (DIGI), another eight frameworks using the Cerec Inlab system (INLA). Vita Inceram Zirkonia blanks were used for both groups. In a third group frameworks were milled from yttrium-stabilized Zirconium blanks using the Lava system (LAVA). All frameworks were layered with ceramic veneering material. In addition, six three-unit metal-ceramic FPDs served as control group. All FPDs were evaluated using a replica technique with a light body silicone stabilized with a heavy body material. The replica samples were examined under microscope. The medians of marginal gaps were 75 µm for DIGI, 65 µm for LAVA and INLA and 54 µm for the conventional FPDs. Only the DIGI data differed significantly from those of the conventional FPDs. Within the limits of this study, the results suggest that the accuracy of CAD/CAM generated three-unit FPDs is satisfactory for clinical use. [source] Patients' experiences with partial dentures: a qualitative studyGERODONTOLOGY, Issue 4 2005Patricia A. Smith Objective:, The aim of the study was to gain insight into people's experiences of being given and using partial dentures. Methods:, In-depth semi-structured interviews were carried out with 23 people of varied age, social background and denture wearing experience in Tayside, Scotland. Participants were encouraged to discuss how they came to have partial dentures, their day-to-day denture use and their interactions with dentists. The interview data were systematically coded using key theme headings, and summary charts were constructed to facilitate analysis. Results:, The initial decision that a partial denture was needed was generally difficult to accept. People perceived the main benefits of partial dentures to be improved appearance and confidence, but experienced a variety of difficulties with their dentures and often coped with these by only wearing them on social occasions. Participants had not always told their dentists about the difficulties they experienced. Barriers to seeking help with denture problems included financial constraints, previous experience of rushed appointments or poor communication from dentists and a perceived lack of entitlement to help when partial dentures were issued free. Conclusions:, Partial dentures can be difficult to cope with. People experience a range of difficulties in wearing them, not all of which have been discussed with dentists. Informative and supportive communication when partial dentures are first needed, and subsequently, can improve the quality of patients' experiences and may help promote effective use and appropriate help-seeking by partial denture wearers. [source] | |||||||||||||||||||||||||