An outline of pre- and post-operative prosthetic treatment for patients with a surgical defect of the palate.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Maximal occlusal force and oral tactile sensibility were recorded in 21 edentulous patients wearing maxillary complete dentures and mandibular fixed prostheses supported by Brånemark implants. Bite force was measured with a miniature force transducer between antagonistic molars and premolars, and the passive tactile sensibility of the fixtures was recorded in the horizontal and vertical directions with spring balances. The active tactile sensibility was tested using steel foils (100 to 10 microns). The range of maximal occlusal force recorded was from 35 to 330N with highest values observed on the second premolars (mean 143N). Significantly lower forces were found on molars and first premolars (p < 0.01). The detection threshold of minimal pressure was about 330 g in the horizontal, and 388 g in the vertical direction. This difference was not statistically significant. The average number of incorrect assessments when testing steel foils was 16.6 errors, out of 100 recordings. Similar results when using these 3 test modalities had been found on overdentures supported by two mandibular implants and occluding with maxillary complete dentures. The results of this study suggest that mandibular implants supporting fixed prostheses are not likely to improve oral tactile sensibility and maximal occlusal force in the presence of maxillary complete dentures.
This retrospective study was designed to verify the factors that influence implant failures. Six prosthodontic clinics in Sweden participated in the study, and together they included a total of 54 patients treated between January 1988 and December 1996. All patients were completely edentulous in the maxilla, and received either a fixed prosthesis or an overdenture supported by at least 4 implants (Brånemark System). Half of the patients belonged to the study group, and an inclusion criterion for this group was that they had lost at least half of their implants. To reduce bias, the patients in the control group were matched to the study group, i.e. they were selected so that both groups were as identical as possible. The results of the study indicate that the control group had a better initial bone support than the study group. Furthermore, the patients in the study group suffered from circumstances that could induce implant failure, such as bruxism, personal grief, depression, as well as addictions to cigarettes, alcohol and/or narcotics. On the study form the clinicians were asked to give their own opinion of the reason for implant failure. The answers given could easily be grouped into 5 different topics, and this experience can be useful to improve patient selection. This study suggests that there are certain factors of importance to consider to prevent a cluster phenomenon of implant failures i.e. lack of bone support, heavy smoking habits and bruxism.
UNLABELLED: Implant overdentures and conventional prostheses have been compared in several trials using a variety of functional and oral health-related quality of life (OHQOL) outcomes. In this paper, we describe the impact of implant overdentures on general and OHQOL in seniors. OBJECTIVES: To compare the oral health-related and general quality of life of seniors (aged 65-75 years) who received either mandibular implant overdentures or conventional dentures. METHODS: Sixty edentulous patients were recruited. Thirty received mandibular overdentures retained by two implants (IOD) and a conventional maxillary denture, the other 30 subjects received new maxillary and mandibular conventional complete dentures (CD). All completed the 20-item version of the Oral Health Impact Profile (OHIP-20) before treatment, then at two and 6 months after delivery of the dentures. The SF-36 general health questionnaire was completed at baseline and 6 months only. RESULTS: Pretreatment and 6-month data from 55 subjects were analyzed. Those who received the IODs had significantly better OHIP-20 total scores at 6 months. Results for IOD subjects were also superior in the functional limitation, physical pain, physical disability and psychological disability subscales. While no significant between group difference was found on the SF-36 health survey, significant pre-post-treatment differences within the IOD group were detected for the role emotional, vitality and the social function scales. CONCLUSIONS: Mandibular overdentures retained by two implants provide elderly patients with better OHQOL. General health-related quality of life improved in the implant group.
It could be hypothesised that attachments, which provide more retention against vertical and horizontal dislodgement, will be associated with more favourable parameters of oral function. This in vivo study is designed to provide data regarding initial retention force, loss of retention force after 3 months of function and postinsertion maintenance and complications associated with the use of magnet, bar-clip and ball attachments in mandibular overdenture treatment. Eighteen edentulous subjects received two permucosal implants in the inter-foramina region of the mandible, a new denture and three successive suprastructure modalities (magnet-, bar-clip and ball attachments). The retention force of the attachments at baseline and after 3 months was measured in a standardised way. The amount and type of postinsertion maintenance that was related to the attachment were evaluated. No differences in retention force at baseline and after 3 months of loading were observed for all three attachment types. The mean retention forces of magnet attachments, bar-clip attachments and ball attachments were 8.1, 31.3 and 29.7 N respectively. Functional maintenance complications related to the attachments were predominantly observed in 11/36 magnet attachments. Functional problems in the ball attachment group were relatively rare, easily manageable and seen in 4/36 attachments. The bar-clip attachments exhibited no maintenance problems at all.
Lateral cephalometric films were obtained from 10 subjects treated with maxillary complete dentures opposed to bar-supported mandibular removable partial dentures. The amount of bone resorption was determined following a 5-year period of denture use. In the maxilla, slight resorption was observed; a considerable amount had taken place in the mandible. Comparing the results of previous studies with the present one, it is suggested that bar-supported mandibular free-end saddle partial denture design has beneficial effects in terms of reduced bone resorption.
To test the hypothesis that titanium (Ti) removable partial dentures (RPDs) would function for a period of at least 2 years without failure, 10 patients were selected to receive dentures made from Ti and Co-Cr. The Ti RPDs were constructed identically to conventional cobalt-chromium (Co-Cr) dentures. Five complete Ti dentures were also included and the laboratory procedures involved for making both complete and partial dentures were evaluated. The detection of internal defects by radiography made the screening of Ti castings possible and led to a rejection of specimens showing porosities of more than 0.5 mm in flexible members. Co-Cr frames on the other hand cannot be screened in this way. The success rate in the casting of Ti was 60% for both partial and complete dentures, but as casting technology has since improved, the rate is expected to be higher, particularly where complete denture palates have optimum thickness. The success rate in the casting of Co-Cr RPDs was 100% without radiographic screening. The weight difference between Ti and Co-Cr RPDs was in the range of 1.3 to 3.9 g at issue and is generally higher as the volume of denture frames increases. A large difference would be of clinical significance in maxillary complete dentures. The low density of Ti allows for the adoption of a useful pre-clinical quality-control process using commonly available dental X-ray units.
A removable denture designed using a three-dimensional cast metal framework (hereafter referred to as the 'structurally designed' denture) could extend denture longevity because it is unbreakable and easy to adjust. The aim of the present clinical study was to compare two types of maxillary removable dentures: conventional dentures and structurally designed denture. One edentulous and five partially dentate patients were fitted with two maxillary dentures made from the same impression and same occlusal relationship. About 20 days after delivery of the denture, masticatory analysis was conducted chewing phase (open, closed, and occluded); coefficients of variation and average variation were calculated. Denture vibration during tapping was then measured using an accelerometer. The patients were also interviewed about comfort, ease of chewing, speech, stability, aesthetics and preference for regular use. For both masticatory movements and denture vibration, there were no significant differences (P>0.1) between the conventional denture and the structural design denture. In evaluating the dentures according to each criteria, the significant superiority of one denture over the other could not be determined. However, all patients subjectively preferred the structurally designed dentures for regular use. According to these findings, structurally designed dentures do not appear to have any particular physiological problems as compared with the conventional dentures.
PURPOSE: The goal of this multicenter prospective clinical trial was to compare clinical outcome and post-treatment care and patient satisfaction with different implant systems used for mandibular overdenture treatment during a 6-year follow-up period. PATIENTS AND METHODS: A total of 87 edentulous patients with a severely resorbed mandible (bone height, 8 to 15 mm) received treatment involving either 2 Intra Mobiele Zylinder implants (IMZ group, n = 41) (Friedrichsfeld AG, Mannheim, Germany), 2 Brånemark implants (Brå group, n = 17) (Nobel Biocare AB, Gothenburg, Sweden) or a Transmandibular Implant (TMI; Krijnen Medical, Beesd, The Netherlands) (TMI group, n = 29). The evaluation involved clinical parameters, radiographs, surgical and prosthetic post-treatment care, clinical implant performance (CIP scale), and patient satisfaction. RESULTS: After 6 years, there was a significant difference in the mean plaque index:the mean plaque index of the TMI group was significantly higher than that of the IMZ and Brå groups. Other clinical parameters showed no significant differences. The implant survival rate of 97.5% was noted in the IMZ group, 97.1% in the Brå group, and 72.0% in the TMI group. The CIP scale were significantly worse for the TMI group. CONCLUSION: It was concluded that the IMZ and the Brånemark implant systems have a better survival rate and clinical implant performance than the TMI system. Based on these data, these systems should be the choice for the edentulous mandible with a height between 8 and 15 mm.
Head and neck surgery may involve complex methods of composite reconstruction that do not replicate the volume and contour of the normal anatomy. 'Functional' reconstruction implies replication of the normal volume and contour of both hard and soft tissues to produce normal form and function of the face, mouth and jaws. Techniques such as stereoscopic lithography and computer-assisted design, and-manufacture (CAD-CAM) have been successfully used with computer-numerized control (CNC) milling to manufacture customized titanium implants for single-stage reconstruction of the maxilla, hemimandible and dentition without the use of composite flap cover after the removal of tumours. Reduction in theatre time and personnel, less need for intensive care, and earlier discharge from hospital, indicate possible savings of Pound Sterling 17,000-Pound Sterling 19,000 per patient. There are implications for surgery in general, and further research and development is advocated.
The vascularized iliac crest graft with internal oblique muscle as a method of reconstruction after maxillectomy has been used routinely at the Regional Maxillofacial Unit in Liverpool since 1993. Twenty-four consecutive operations have now been done and this paper reports an audit of our experience. An analysis of case-notes was made retrospectively after checking theatre diaries and records. A detailed inspection of the case-notes was undertaken to ascertain the presenting diagnosis, the complications and the outcome in terms of recurrence and disease survival. The type of defect was recorded, as was whether it had been possible to rehabilitate the patient both dentally and facially. At the time of this study 9 patients (38%) had died of their disease leaving 15 surviving. In 13 cases full dental and facial rehabilitation had been achieved or patients were waiting for an implant-retained prosthesis. Donor site problems important enough to be recorded in the notes were minimal, one case of abdominal wall weakness was noted, which required no intervention. The vascularized iliac crest graft with internal oblique muscle offers a complete solution for reconstruction after maxillectomy, providing there has been no sacrifice of the overlying facial skin and oral sphincter. There is sufficient height and depth of bone to maintain a facial profile and the muscle epithelializes to provide an ideal oral and nasal lining. This flap provides a base to enable full dental and facial prosthetic rehabilitation with either implant-retained or conventional prostheses.
STATEMENT OF PROBLEM: It has been suggested that risk for severe resorption in the anterior maxilla is increased in persons wearing mandibular implant-retained overdentures. However, little information is available about the changes in the edentulous maxilla after mandibular implant treatment. PURPOSE: This study determined the possible changes in the width of the maxillary residual ridge 6 years after receiving mandibular implant-supported or implant-mucosa-supported overdentures and evaluated the association between the anatomic changes and subjective complaints with maxillary complete dentures. METHODS AND MATERIAL: The subjects for this study (n = 55), enrolled among the participants of a prospective clinical trial, were randomly assigned into 3 groups treated with: (a) implant-supported overdentures on a transmandibular implant system (n = 21); (b) implant-mucosa-supported overdentures on 2 IMZ implants (n = 20); or (c) conventional complete dentures (n = 14). A lingual contact occlusion concept with anterior open bite was used for tooth arrangement in all subjects. Diagnostic casts were made at baseline, and again at the 6-year follow-up. Most prominent points perpendicular to the crest of residual ridge were located in the incisor, canine, and premolar regions, after which the width of the ridge was recorded at these points with a Boley gage. Subjects' opinions on their dentures were evaluated with a questionnaire. RESULTS: Significant reduction in the width of the ridge was found in all measurement areas (mean difference = 0.4 to 0.6 mm; P <.0001). However, changes were small and not associated with the type of prosthetic restoration in the mandible. In subjects with implant-mucosa-supported overdentures, complaint of loose maxillary denture correlated with the decrement of residual ridge width. CONCLUSION: The width of residual ridge decreases with time, despite the type of mandibular prosthetic restoration.
STATEMENT OF PROBLEM: In this preliminary study, an attempt was made to measure in vivo forces simultaneously on 5 maxillary implants with different types of superstructure. MATERIAL AND METHODS: Force measurements were carried out on 1 test patient with 5 ITI implants in the edentulous maxilla. A screw-retained fixed complete denture and an overdenture were fabricated for comparative measurements of forces. The overdenture could be mounted to 2 different types of bars. The measuring method was used with piezo-electric force transducers that were directly mounted onto the implants. This allowed for simultaneous measurements of forces in 3 dimensions, ie, in axial and transverse directions. Static and functional forces such as maximum biting (clenching), biting on a bite plate, and chewing food were registered. All measurements were repeated in the same way 2 years later. RESULTS: The registered forces exhibited similar force patterns with both types of superstructure and both types of bars for overdenture connection. The force magnitudes were significantly different for the 3 dimensions (P<.05) with highest forces along the implant axis. On the posterior implants, force magnitudes were significantly higher (P<.05) than on the anterior implants in all 3 dimensions. On the anterior implants, under some test conditions, the transverse force components reached up to 100% of the axial force or even exceeded it during the chewing of food. During maximum biting, no upward force (tensile force) was found on any implant with the fixed complete denture, but upward force was found on one anterior implant with the overdenture. When chewing food, small force magnitudes in upward directions were regularly found with both superstructures. The force patterns between the first and second registrations showed similar trends, and no obvious differences were found. CONCLUSION: From these results it was concluded that similar patterns of force transmission onto the implants are observed with a fixed complete denture and an overdenture connected to maxillary implants. The bar design did not significantly influence the force pattern.
Explore the source record for details and available documents.
The prosthodontic rehabilitation of a patient with a recurrent maxillary CGCG has been described. The patient's immense defect originally was rehabilitated with a scapular microvascular free flap, endosseous dental implants, and an ISP that became obsolete by virtue of the resection of recurrent disease and the subsequent need for velopharyngeal obturation. The patient was provided with a surgical obturator at the time of the resection of the recurrent CGCG. The surgical obturator thereafter was modified into an interim obturator to provide velopharyngeal competence while the soft tissues around the palatal defect healed. Finally, the construction of a bar-retained definitive obturator markedly improved the patient's speech, mastication, and deglutition.
STATEMENT OF PROBLEM: Masticatory muscle hyperactivity is thought to produce muscle pain and tension headaches and can cause excessive wear or breakage of restorative dental materials used in the treatment of prosthodontic patients. The quantification and identification of this type of activity is an important consideration in the preoperative diagnosis and treatment planning phase of prosthodontic care. PURPOSE: This study investigated the quantification process in complete denture/overdenture patients with natural mandibular tooth abutments and explored the reliability of instrumentation used to assess this parafunctional activity. MATERIAL AND METHODS: The nocturnal EMG activity in asymptomatic complete denture/overdenture subjects was assessed with and without prostheses worn during sleep. Because of the large variance within and between subjects, the investigators evaluated the reliability of the 3 instruments used to test nocturnal EMG activity in the sample. RESULTS: Electromyographic activity data of denture/overdenture subjects revealed no differences between prostheses worn versus not worn during sleep but demonstrated a very large variance factor. Further investigation of the instrumentation demonstrated a consistent in vitro as well as in vivo reliability in controlled laboratory studies. CONCLUSION: The portable EMG instrumentation used in this study revealed a large, uncontrollable variance factor within and between subjects that greatly complicated the diagnosis of parafunctional activity in prosthodontic patients.
This clinical report describes the fabrication of an immediate complete denture for a patient with an extensive fixed prosthesis that was no longer serviceable because of major loss of integrity of the supporting abutment teeth. The procedure, which was performed chairside, replicated the existing fixed prosthesis as part of an immediate complete denture.
STATEMENT OF PROBLEM: The specific degree of retention for overdenture attachments is unknown in relation to design, location, and alignment to supporting dental implants. PURPOSE: The purpose of this study was to evaluate the initial retention characteristics of 5 implant maxillary overdenture designs under in vitro dislodging forces. MATERIAL AND METHODS: A simulated edentulous maxilla was fabricated with 4 screw-type 3.75 x 13-mm implants anteriorly. Five overdenture designs with the following attachments were evaluated: 4 plastic Hader clips with an EDS bar; 2 plastic anterior Hader clips with an identical EDS bar; 2 Hader clips with 2 posterior ERA attachments; 3 Zaag attachments on a bar; and 4 Zaag attachments with no bar. Overdentures were fabricated with full palatal coverage. Each design was subjected to 10 consecutive retention pulls on a universal testing machine. Data were subjected to analysis of variance and t tests to determine differences. RESULTS: The highest average value after 10 pulls was 19.8 lb for the combination ERA and Hader clip design. The lowest retentive values were recorded for the 2 and 4 Hader clip designs (5.08 +/- 0.89 lb and 5.06 +/- 0.67 lb, respectively). Retention decreased over the course of consecutive pulls for all designs, especially for the most retentive designs. The smallest retention decrease occurred with the least retentive designs. CONCLUSION: The results of this in vitro study suggest that the precise selection and placement of attachments may affect the clinical success of maxillary implant-retained overdentures.