Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Prosthesis Retention”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed1994

Achieving a passive fit for a screw-retained implant-supported maxillary complete arch ceramometal prosthesis: clinical report.

A technique is described for the fabrication of a full arch maxillary passive-fitting, screw-retained, rigid ceramometal prosthesis. The two posterior segments containing Screw-Bloc attachments are cast initially. The waxed anterior segment with its attachments is then aligned to the cast posterior segments and cast. Porcelain is fired to the individual segments in an attempt to reduce deformation, which occurs when large ceramometal restorations are constructed. When the prosthesis is completely fabricated, the segments are assembled on the master cast and the attachments on the posterior segments are tapped to receive the screws, which rigidly attach them to the anterior segment. The Screw-Bloc attachment has an irregular configuration that resists rotation of the individual segments. The segments are united once the passively aligned screws are tightened. A clinical report is presented.

Dental Implants↗
PubMed2003

A comparison of the retention of tooth-colored posts.

OBJECTIVE: The aim of this in vitro study was to compare the retention of five different esthetic post systems of similar dimensions in extracted teeth using titanium posts as controls. METHOD AND MATERIALS: Sixty recently extracted single-rooted, caries-free teeth were sectioned horizontally and mounted in acrylic resin. The samples were randomly allocated into six groups of 10 for post preparation. Post space preparation was carried out according to the individual manufacturer's instructions. All posts were bonded using Panavia F. A 4-mm hollow, metal sleeve was luted over the free end of each post prior to mounting in a universal testing machine, and the forces required to dislodge the posts using a cross-head speed of 5 mm/min were recorded. RESULTS: It was found that the parallel-sided Lightposts were significantly more retentive than all of the other posts. Parapost Fibrewhite posts were more retentive than tapered Lightposts and Snowposts. There was no significant difference between the retention of stainless steel Paraposts and any of the other groups. CONCLUSIONS: Serrated parallel-sided stainless steel posts were no more retentive than either parallel-sided or tapered tooth-colored posts in this study. When all groups were considered, post dimension appeared to influence retention, with parallel-sided posts being more retentive than tapered posts.

Ceramics↗
PubMed1992

Tissue-integrated prosthesis complications.

Over a 78-month period from 1983 to 1990 at the Mayo Clinic, 353 patients involving 407 jaws were restored with 1,778 Brånemark system implants supporting prostheses. Complications involved loss of implant anchorage, soft tissue problems, or mechanical problems. The most predominant complication involved soft tissues. There were 152 patients with loaded prostheses who had no complications and 37 with only one occurrence. Those seen in 160 patients with more than one occurrence were all conservatively managed, so that prosthesis use was only permanently discontinued in 4 patients, who returned to the use of a maxillary complete denture.

Adolescent↗
PubMedDate not supplied

ITI titanium plasma-sprayed screw implants in the treatment of edentulous mandibles: a follow-up study of 39 patients.

The outcomes of 153 ITI titanium plasma-sprayed screw implants were studied in 39 patients. Four implants were placed in the edentulous mandible between the mental foramina and used as support for a denture prosthesis. Thirteen implants in six patients had been lost during the follow-up time of 3 to 10 years (mean 5.6 years). The mean annual bone resorption was 0.25 mm (SD 0.29 mm; range 0 to 1.37 mm). Bone loss was smaller in patients with prosthetic loading applied within 7 postoperative days than in those with delayed prosthetic treatment. No evidence of bone loss was seen around 37 (26.4%) implants. The cumulative and overall success rates for titanium plasma-sprayed implants were 80.8% and 91.5%, respectively. The corresponding figures for the patients were 86.8% and 94.9%.

Adult↗
PubMedDate not supplied

The relationship of Periotest values, biomaterial, and torque to failure in adult baboons.

A quantitative measure of implant stability would be beneficial to decision-making regarding the status of the bone anchorage around an implant. The Periotest device has been reported to provide such a measure, but the in vivo data are incomplete and inconclusive in support of this claim. The purpose of this study was to determine in an in vivo model the relationship between Periotest values (PTV), three different implant biomaterials, and torque to failure. A total of 79 screw-shape implants made of commericially pure titanium, titanium alloy, and HA-coated alloy were evaluated in the posterior maxillary and mandibular quadrants of six female baboons following healing for 3 to 4 months. At uncovering, the implants were tested with the Periotest device and torqued to failure using an electronic torque driver. Analysis of the PTV-biomaterial relationship revealed no significant difference among the implants based on the biomaterial (P = .7453). Analysis of PTV-torque revealed a significant relationship (P = .0117), however, the association between PTV and torque was not strong and does not explain 92% of the variation between the parameters (Pearson correlation .2823, R2 = .08).

Analysis of Variance↗
PubMedDate not supplied

Failure strength of four veneered primary stainless steel crowns.

The purpose of this study was to determine the amount of shear force required to fracture or dislodge the veneered facings of four commercially available veneered primary incisor stainless steel crowns (SSC) and to characterize the veneer failures. Forty Unitek SSCs (#4 left central incisor) were shaped to fit a master die and then 10 each were mailed to four commercial dental laboratories that produce veneered SSCs. The resulting four types of crowns tested were: Cheng Crowns (CC), [Peter Cheng Orthodontic Laboratory]; Kinder Krowns (KK) [Mayclin Dental Studio, Inc]; NuSmile Primary Crowns (NC), [Orthodontic Technologies, Inc]; and Whiter Biter Crown II (WB), [White Bite Inc]. Each crown was cemented onto a standardized die and then thermocycled at 4 degrees C and 55 degrees C for 500 1-min cycles. Each die was then placed into a custom holder on the Instron (Model 4204) testing machine. A force was applied at the incisal edge of the veneer at 148 degrees, (the primary inter-incisal angle), with a crosshead speed of 1 mm/min until the veneer fractured or was dislodged. The mean force (N) required +/- SD to produce failure was, respectively: KK (397.2 +/- 53.0); NC (447.2 +/- 78.5); CC (511.9 +/- 83.4); WB (686.5 +/- 181.4). Analysis of variance (ANOVA) indicated significance at P < 0.0001. A Scheffe's post hoc comparison demonstrated that the Whiter Biter (WB) group required significantly (alpha = 0.05) more force for failure than the other three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1996

Tinted luting resin for partial-coverage restorations: a case report of a new provisionalization technique.

A number of practical problems may be encountered when a dentist attempts to provisionalize an indirect restoration. Problems that relate to provisional restorations for conservative, less retentive, ceramic cavity forms are discussed. A provisionalization technique that improves marginal integrity, assures predictable retention, and facilitates cleanup following detachment is introduced.

Acrylic Resins↗
PubMed2000

Effect of prefabricated metal post-head design on the retention of various core materials.

Retention of various post heads to core restorative materials is an important factor in the selection of prefabricated post systems and restorative materials for the restoration of endodontically treated teeth. This study examines the retention of a post-core prefabricated system in relation to core material and post-head design. A total of 60 samples were prepared using two different post systems (ParaPost Plus (PP) and ParaPost Unity (PU), with amalgam, composite or glass-ionomer as one of the core materials. The samples were tested using the Instron testing machine. The PP was superior to the PU prefabricated post with respect to the retention of various core materials. Retention values in descending order of magnitude were found to be: composite, amalgam and glass-ionomer (significantly lower). The rhomboid serrated design of PP was superior in retention to the rounded smooth UP system. Composite material proved to be superior in retention, closely followed by amalgam, with glass-ionomer significantly less retentive.

Analysis of Variance↗
PubMed2004

Parameters affecting retentive force of conus crowns.

The aim of this study was to determine the values of the retentive forces of the telescopic crowns. At the first step of the study, the samples having different heights and angles were compared in relation to retentive force. At the second step, the samples were subjected to removal procedures having a pre-determined speed, force and number. The obtained retention values were compared. Ninety dies were prepared in order to measure the retention of the conus crowns. The removal tests were performed with the insertion/separation device. The speed of the test device was 100 cm min(-1) providing the placement of the pieces with 5 kgf in 100, 200, 300, 500, 1000, 5000 and 10 000 cycles. The mean of the retention values of the changes of the angles were found to be statistically different (P < 0.01). According to the results of the variant analysis, the differences in the changes of the height were statistically significant (P < 0.01). The differences between the changes of the number of procedures of all groups were statistically significant (P < 0.01). The number of procedures, height and angle interactions were statistically insignificant (P = 0.758). According to the results of this study, the effect of the angle and height factors in terms of retention among the groups were not independent of each other. In equal angles, as the height increased, increased retention measurements were obtained. In more acute angles, the increase in retention was more obvious. It was also found that an accessory device was necessary to maintain retention capabilities after a long-term use.

Crowns↗
PubMed2003

[The measurement of retentive forces in mandibular complete overdenture with Magfit magnetic attachments].

OBJECTIVE: To evaluate the in vivo retentive forces of mandibular complete overdenture with Magfit attachments, as well as the relation between the location of magnetic attachments and the retentive forces of the denture. METHODS: 5 patients were selected and treated with mandibular complete overdentures retained by Magfit EX600 and MD800 attachments. A strainometer was used to measure the retentive forces in anterior, central and posterior parts of the overdenture before and after magnets were set. The vertical and anterior-upper 60 degrees retentive forces of the overdenture were measured one month later. RESULTS: The retentive forces of the overdentures after setting magnets were significantly greater than that before magnets were set (P < 0.05). There was no significant difference in retentive forces between the different parts (P > 0.05). The retentive force in vertical direction was greater than that in anterior-upper 60 degrees direction (P < 0.025). CONCLUSION: Magnetic attachments can significantly improve the retention of mandibular complete overdenture. The location of magnetic attachments greatly influences the retentive force of the overdenture.

Aged↗
PubMed2003

[The significance of the size and type of surface of prepared teeth for retention of permanent dentures fixed with zinc-phosphate cement].

The purpose of this paper was to establish, in vitro, the impact of different sizes and prepared teeth roughness on the adhesion strength with cast crowns. Twenty human intact premolars were used in the experiment. They were prepared and divided into two groups depending on the fineness of diamond prepared instrumentation. Sizes of prepared teeth were calculated mathematically, while the dentine roughness was measured by a profile meter. The cast crowns were made by a standard method for each group. The crowns were then cemented with a zinc phosphate cement. After seven days, testing of prepared teeth and cast crowns bonding strength was carried out mechanically in an electronic dynamometer. On the basis of the obtained results the relationship between the size and the accomplished roughness with the obtained values of the retention forces is observed. At the constant convergence angle of the stamp the retention is proportional to the stamp size and the roughness profile.

Chromium Alloys↗
PubMed1995

A 10-year literature review of a split-shanked threaded post.

A review of 10 years of literature on prefabricated threaded and passive post systems is presented along with recent literature supporting the validity of the split-shanked threaded post design, Flexi-Post. It is important to note that a split-shanked threaded post is altogether different from a solid-shanked threaded post. The research discussed in this article confirms the high retention of the Flexi-Post and dispels the notion that high retention must be accompanied by high stress.

Dental Prosthesis Design↗
PubMed1994

Assessment of implant mobility at second-stage surgery with the Periotest: DICRG Interim Report No. 3. Dental Implant Clinical Research Group.

Many of the presently used methods of evaluating osseointegration at implant uncovering are highly subjective. The Periotest is claimed to offer a more objective means to assess osseointegration by means of microcomputer-controlled percussion. Investigators involved in a long-term clinical study of dental implants being conducted by the Dental Implant Clinical Research Group used the Periotest to evaluate the mobility associated with all study implants at second-stage surgery and correlate the Periotest values with various bone densities. The Periotest values for 1,838 root form implants ranged from -8 to +25. Implants that appeared to be osseointegrated at uncovering recorded a mean Periotest value of -3.37 +/- 3.25, while nonosseointegrated implants had a mean Periotest value of +13.87 +/- 14.27. Mean Periotest values were -3.82 +/- 3.04 for quality 1 bone, -3.70 +/- 3.06 for quality 2 bone, -3.31 +/- 3.18 for quality 3 bone, and -1.29 +/- 3.57 for quality 4 bone. The Periotest has the potential of being a valuable instrument for assessing the status of osseointegration at second-stage surgery.

Alveolar Process↗
PubMed1995

The Christensen prosthesis. A retrospective clinical study.

The objective of this study was to determine if the Christensen temporomandibular joint prosthesis system in an effective alternative in treating patients with severe temporomandibular joint disorders. A total of 69 patients who were not responsive to either nonsurgical or prior surgical treatments were placed into one of three treatment groups depending on the following diagnoses: (1) placement of a glenoid fossa-eminence prosthesis with meniscus retention (22 patients, 40 joints); (2) placement of a glenoid fossa-eminence prosthesis without retention of the meniscus (26 patients, 49 joints); (3) total joint replacement (21 patients, 34 joints). Patients were evaluated immediately before surgery and at regular intervals after surgery for an average of 3.1 years. Success was measured as a significant improvement of function and decrease in pain as measured on a visual analogue scale, as well as improved incisor opening as measured with a Therabite Scale (Lorenz Surgical, Jacksonville, Fla.). Comparison of mean and average pre- and postsurgical values for all groups and criteria showed significant improvement. Results of this study indicate that the Christensen temporomandibular joint prosthesis system may offer a viable method for the treatment of severe temporomandibular joint disease with a high degree of success.

Adult↗
PubMed2007

Influence of attachment wear on retention of mandibular overdenture.

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

Dental Abutments↗
PubMed1995

Comparing the resistance of dentin bonding agents and pins in amalgam restorations.

This in vitro study involving 84 caries-free molar specimens examined the resistance of complex amalgam restorations retained by two dentin bonding agents--Amalgambond and Amalgambond Plus--four regular TMS pins, six regular TMS pins and four pins in conjunction with Amalgambond. Analysis indicated that the Amalgambond restorations were significantly weaker than the other types. Amalgambond Plus restorations were significantly stronger than the Amalgambond restorations but not different from the remaining groups. The authors concluded that complex amalgam restorations should be retained with a combination of adhesive and mechanical retention.

Analysis of Variance↗