SEARCH · Search PubMed
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.
Dental practices will see an increasing number of older patients as our population ages over the next decade. The following article describes a denture repair in a patient with Parkinson's disease. The patient and his caregiver were unable to make multiple trips to the clinic for treatment. The type of repair described in this article minimized the amount of expense and time required to repair the denture.
Osseointegrated implants are often used for mandibular denture retention. Although clinical success rates are high, complications can occur. A specific clinically relevant example of a fractured bar is presented along with a procedure for its repair. This procedure allows the repair to be done in a timely and cost-efficient manner.
A technique is described for repositioning the clip attachments of implant overdentures during repair or relining procedures using a direct method. During maintenance procedures, clip attachments must be repositioned correctly to prevent torquing of the bar and abutments and precautions taken to avoid locking the prosthesis to the undercut areas of the bar. This technique ensures proper positioning of the attachments and decreases the amount of polymerization shrinkage.
The use of many currently available implant systems may be limited in patients with severe mandibular atrophy because of the lack of available bone in the symphyseal region. The transmandibular implant is a rigid box-frame structure that can distribute masticatory forces along a severely atrophied mandible with as little as 4 mm of vertical bone with an implant-borne prosthesis. Although the success rate of the transmandibular implant is favorable as compared with other systems, complications can occur after placement, including infection, partial extrusion, and fracture of a post. A case report of fractures of two posts at the necks and the bar approximately 18 months after placement is presented.
BACKGROUND: Although many studies report high survival rates of mandibular implants supporting an overdenture, complications with prostheses and the need for prosthetic maintenance are not so well documented. PURPOSE: The purpose of the present study was to analyze three categories of prosthetic complications in relation to the type of retention mechanism for overdenture connection to the implants (ie, rigid or resilient). MATERIALS AND METHODS: One hundred nineteen patients with a total of 258 implants participated in the study. They had been monitored regularly during an observation period of 5 to 15 years (mean 9.3 yr). Seventy-five patients had a resilient retention device (ball anchors or a round clip bar); 44 patients had a rigid bar with or without distal extensions. The incidence and rate of complications were calculated for the overall- and for the 2- and 5-year observation periods. Comparisons were made between the three categories of maintenance and the two types of retention. A Kaplan-Meier analysis was applied for calculations of changes of the retention mechanism. RESULTS: The mean number of complications per overdenture during the entire observation period was 3.5; this did not differ statistically between the two retention groups. Some significant differences were found only for the 2- and 5- year period. Broken, loose, or lost female parts were more frequently observed with resilient devices, as were repairs and relining of the resin denture base, whereas tightening of bar retainers was more typical with rigid bars. A change from a resilient retention device to a rigid bar was performed more often than vice versa but not at a statistically significant level. CONCLUSION: Although these long-term results do not indicate a significant difference between the retention groups, a slight superiority of the rigid bar is suggested.
PURPOSE: The aim of this in vivo study was to evaluate the clinical performance of porcelain veneers after 5 and 10 years of clinical service. MATERIALS AND METHODS: A single operator placed porcelain laminates on 87 maxillary anterior teeth in 25 patients. All restorations were recalled at 5 years and 93% of the restorations at 10 years. Clinical performance was assessed in terms of esthetics, marginal integrity, retention, clinical microleakage, caries recurrence, fracture, vitality, and patient satisfaction. Failures were recorded either as "clinically unacceptable but repairable" or as "clinically unacceptable with replacement needed". RESULTS: Porcelain veneers maintained their esthetic appearance after 10 years of clinical service. None of the veneers were lost. The percentage of restorations that remained "clinically acceptable" (without need for intervention) significantly decreased from an average of 92% (95 CI: 90% to 94%) at 5 years to 64% (95 CI: 51% to 77%) at 10 years. Fractures of porcelain (11%) and large marginal defects (20%) were the main reason for failure. Marginal defects were especially noticed at locations where the veneer ended in an existing composite filling. At such vulnerable locations, severe marginal discoloration (19%) and caries recurrence (10%) were frequently observed. Most of the restorations that present one or more "clinically unacceptable" problems (28%) were repairable. Only 4% of the restorations needed to be replaced at the 10-year recall. CONCLUSION: It was concluded that labial porcelain veneers represent a reliable, effective procedure for conservative treatment of unesthetic anterior teeth. Occlusion, preparation design, presence of composite fillings, and the adhesive used to bond veneers to tooth substrate are covariables that contribute to the clinical outcome of these restorations in the long-term.
PURPOSE: The purpose of this study was to report on the clinical characteristics and outcome of 688 single-unit metal-ceramic crowns placed in a specialist prosthodontic practice between January 1984 and December 1992. MATERIALS AND METHODS: Clinical and laboratory techniques were standardized and patients were recalled by the author between June and December of 1993. The outcome of all crowns was allocated to one of 6 fields in this assessment period. RESULTS: Clinical review examination by the author covered 87% of the crowns. Of these, 52% had been in service for 5 to 10 years and 48% for less than 5 years but more than 1 year; 67% of the crowns were placed on vital teeth and 94% were given a "good prognosis" rating at examination. The repair and failure rates of crowns in the 5 to 10 years in clinical service group were both 3%. Crowns on nonvital teeth in the same grouping had a significantly greater failure rate (5%) than crowns on vital teeth (1%), and anterior teeth had a significantly greater retreatment rate than posterior teeth. Retreatment for all 25 crowns occurred within 66 months after cementation. Tooth fracture accounted for 56% of retreatments, while caries and loss of retention accounted for only 24% of retreatments; 2% of initially vital teeth were endodontically treated during the survey period. CONCLUSION: Single-unit metal-ceramic crowns have a high expectancy of exceeding 10 years of clinical service when the described clinical and laboratory protocol is applied.
Replacement of pin-retained amalgam restorations is complicated by the loss of prime pin sites and remaining pin sites posing anatomical problems. Self-threading dentine pins can be removed with an ultrasonic handpiece, and the pin site reused with a large pin. Retention of replacement pins is similar to original pins. Pin removal after experimental placement takes a considerable time (< 15 min), but pin removal from extracted pin-restored teeth is much quicker (mean of 45 s). The reuse of primary pin sites allows uncomplicated replacement of pin-retained amalgams, and is a useful clinical technique.
With the increased use of cement-retained implant-supported restorations for the replacement of missing teeth, clinicians may choose to use a definitive cement to lute the definitive restoration. A complication that may occur, especially for a single-tooth replacement, is loosening of the abutment screw. In those situations, it may be difficult to locate the abutment-screw access to remove the restoration. The purpose of this article is to describe a technique that may facilitate the clinician's ability to locate the abutment-screw access in the event of abutment-screw loosening, thus reducing the need for refabricating the restoration.
Explore the source record for details and available documents.
Although implant-retained overdentures are a less expensive alternative to fixed implant-supported prostheses in certain situations, problems with retentive clips fracturing and needing frequent replacement have been reported. This study compared baseline and posttest retention of metal and plastic clip-retained overdenture analogs and monitored surface changes in bars and clips throughout the testing process. A laboratory model was made with two implant analogs processed into an acrylic resin platform to which three bars were fitted. Two overdenture analogs were made and retained on the model with metal or plastic clips. Each bar-clip assembly was subjected to 5500 insertion and removal cycles to simulate 3 years of in vivo insertion and removal. Although the differences in retention between metal and plastic clips and between clips before and after testing were statistically significant, it is questionable whether they are clinically significant. Neither clip fracture nor loss occurred during this study, which suggests that it may be functional or parafunctional loading and not repeated insertion and removal of an implant overdenture that may cause the stated problems.
Two independently selected groups of 20 patients who were edentulous in te mandible, were followed up on a regular basis over a 5-year period following restoration with a lower implant stabilised prosthesis and conventional upper denture. Significantly more treatment was required by those who received complete mandibular overdentures than those provided with complete fixed mandibular prostheses. In addition to adjustment for the relief of denture trauma to the mucosa, more mechanical problems arose with overdenture implant prostheses.
A technique for removing a fractured abutment screw and salvaging the endosseous implant is presented. Two commercially available screw retrieval kits are described and discussed.
Explore the source record for details and available documents.
Clinical experience indicates that implant-supported crowns for the replacement of individual molars using the original, regular platform CeraOne protocol (Nobel Biocare) infrequently result in gold screws loosening. This article offers a technique that may prevent the CeraOne gold screw from working loose. It is intended to be a correction for a problem, not a first-time treatment. Also, this is a treatment that should be offered only after the prescribed Brånemark protocol for screw tightening and elimination of excursive contacts has proven ineffective.
Explore the source record for details and available documents.
The use of resin cements in combination with dentin bonding agents can result in superior attachment of prostheses to tooth structure. This paper describes four clinical cases in which dentin-bonded resin cements were used to overcome retention problems. In the first case, a detached fixed partial denture, which was in good condition when separated, was recemented to abutment teeth prepared with less-than-ideal angle of convergence. In the second case, a detached all-porcelain crown was recemented with a dentin-bonded resin cement after appropriate surface treatment. In the third case, a porcelain-fused-to-metal crown made for a molar tooth was cemented to a short clinical crown, avoiding crown-lengthening surgery. In the fourth case, a 3-unit fixed partial denture was recemented to abutments with less-than-ideal supporting features. Dentin-bonded resin cements can help to extend the life of detached prostheses until the patient is financially prepared for replacement or it can help to avoid crown-lengthening surgery.
PURPOSE: The purpose of this study was to evaluate the professional time required for the prosthodontic maintenance events of mandibular implant overdentures during the first year of service using three different implant systems (ITI, Steri-Oss, or Southern). MATERIALS AND METHODS: Seventy-two mandibular implant overdenture patients were allocated to three equal groups, each treated with a different implant system. Data on prosthodontic maintenance events during the first year were categorized and analyzed according to professional time allocation per procedure. RESULTS: The total professional time required to perform all the maintenance events ranged between 29.0 and 34.0 hours and did not differ significantly among the three groups, although there were time differences for matrix activation and replacement. When combining the professional time for all maintenance events for the mandibular overdentures alone, or with the opposing maxillary complete dentures, there were no significant differences between groups. For maintenance of the maxillary dentures, there was an unexplained difference between the Southern group and ITI or Steri-Oss groups (P < .05). CONCLUSION: The prosthodontic maintenance for mandibular implant overdentures required on average 72 to 98 minutes of professional time per patient during the first year of service, depending on the system used.