Dual-space technique for creating cement space in a cementation device for implant dentistry: A predictable chairside approach.

As residual excess cement in peri-implant tissues is a problem that can lead to implant failure, great care must be taken when delivering cement-retained crowns. Cement selection, prosthetic design, and cementation techniques can reduce the chances of having excess cement in peri-implant tissues. Multiple techniques have been described, but, in many, the cement space has been reproduced by unreliable means. The dual-space technique allows the clinician to fabricate an implant crown delivery device in which the cement space has been replicated in a predictable and straightforward manner. In this technique, light-body impression material is used to create the luting space before the fabrication of the device with bis-acryl resin.

Custom abutments alone will not eliminate the clinical effects of poor cementation techniques around dental implants.

With proper planning, placement, prosthetic treatment, and maintenance, dental implants have been shown to be a predictable and reliable treatment option with a high success rate. Clinicians who place cement-retained implant restorations, however, should be aware of the potential and sometimes irreversible biological complications associated with residual excess cement and should be prepared to consider using different practices that may reduce the problem. The present case reports describe the use of custom abutments to restore deeply placed implants with the intent of minimizing residual excess cement.

Effects of abutment and screw access channel modification on dislodgement of cement-retained implant-supported restorations.

This study investigated the influence of implant abutment and screw access channel modification on the retention of copings. Titanium abutment access openings were either left open or modified by placing two vent holes 3 mm from the occlusal edge and 180 degrees apart. Access openings sealed with a resin material were used as controls. Metal copings were cemented and subjected to tensile testing until failure. Access openings with two vent holes resulted in significantly higher mean retention values compared to the opened or sealed screw access groups (P < .05). Cement flow was affected by the internal vent, which increased the area of cementabutment contact.

One abutment-one time: the negative effect of uncontrolled abutment margin depths and excess cement--a case report.

It has been reported that repeated connection and disconnection of transmucosal components stimulates apical repositioning of the soft tissues and marginal bone resorption. Limiting the number of times this occurs may be beneficial. A new treatment concept called one abutment one time describes the placement of the definitive abutment at the time of surgery. This case highlights the susceptibility of excess cement residue associated with this concept and unesthetic outcome even when meticulous surgical correction is attempted.

An introduction to the implant crown with an esthetic adhesive margin (ICEAM).

UNLABELLED: This article describes a novel technique with the addition of a pressed porcelain abutment margin capable of bonding to the porcelain margin of an implant crown restoration. This allows for supragingival margin placement, reduces the potential effect of excess cement-induced peri-implant disease, and provides a controlled environment for the bonding process. Another advantage is the matching esthetics of the crown and supporting abutment, which in the event gingival recession occurs, the restoration appears as a longer tooth without the risk of exposing an underlying abutment margin with different esthetic properties. CLINICAL SIGNIFICANCE: The transition margin from an implant abutment to a crown is challenging to manage especially esthetically. Placing the abutment margin in a subgingival position helps hide the unesthetic transition, however, this reduces the ability to clean excess cement, increases the risk of peri-implant disease and the inability to control gingival sulcular fluids may affect the cement bond. The implant crown with an esthetic adhesive margin provides for supragingival bonded margins that can aid in complete removal of excess cement at the same time providing an esthetically pleasing result.

Cement application techniques in luting implant-supported crowns: a quantitative and qualitative survey.

PURPOSE: To investigate different techniques used by dentists when luting an implant-supported crown and to evaluate the application of cement quantitatively and qualitatively. MATERIALS AND METHODS: Participants were given a bag containing cement sachet, mixing pad, spatula, a variety of application instruments, and a polycarbonate crown form. The participants were instructed with a standardized audio-video presentation to proportion the cement, mix it, and apply it to the intaglio of the crown as they would if they were to cement it onto an implant abutment in a clinical situation. The crowns were weighed, first unfilled and then again once the applied cement had set. The mean weights of fully-loaded crowns (n = 10) were used as a control group. The patterns of cement loading were recorded. The weights of collected cement-loaded crowns were compared to those of the control group and analyzed statistically. RESULTS: Four hundred and one dentists in several different geographic locations were surveyed. Three distinct cement loading patterns were observed: gross application (GA), brush-on application (BA), and margin application (MA). The mean weights for each cement loading pattern were 242.2 mg for the GA group, 59.9 mg for the BA group, and 59.0 mg for the MA group. The weight of cement in the GA group was significantly higher than that in the other groups. No statistically significant difference between groups BA and MA was seen. CONCLUSIONS: The diversity of the cement loading patterns disclosed in this study indicates that there is a lack of uniformity and precision in methods and a lack of consensus in the dental community regarding the appropriate quantity of cement and placement method for a cement-retained implant crown.

Effect of implant abutment modification on the extrusion of excess cement at the crown-abutment margin for cement-retained implant restorations.

PURPOSE: To compare the effect of implant abutment modification on the amount of cement extruded at the crown-abutment margin and to evaluate the vertical discrepancy after cementation. MATERIALS AND METHODS: Access openings of titanium abutments were modified with an opening (open) and placement of two vent holes 3 mm from the occlusal edge and 180 degrees apart (internal vent). Access openings were filled with resin material (closed) and used as controls. Each abutment was secured to an implant analog. Eugenol-free zinc oxide cement (TempBond NE) was selected to cement the cast crowns (n = 9) onto test abutments. The amount of cement extruded out of the margin was calculated, and vertical seating discrepancies were determined with a linear transducer device before and after cementation. Differences among groups were analyzed statistically. RESULTS: The mean amount of extruded cement ranged from 36% to 90% of the total cement placed within the crowns. The order, from least to greatest amount of excess cement extrusion at the margins, was internal vent, open, and closed; significant differences were observed between test groups. The net vertical discrepancies of tested specimens ranged from -7 µm to +6 µm (mean, 0 µm). No statistically significant differences in vertical discrepancy were found between the groups. CONCLUSIONS: Venting the hollow abutment resulted in the least amount of cement extrusion when compared to closing off the screw access channel or leaving it open. Within the limitations of this study, it may be concluded that the use of two, 0.75-mm radius vent holes placed 3 mm apical to the occlusal area of the abutment and 180 degrees apart will limit the amount of cement extruded into the gingival sulcus of implant-retained crowns.

An esthetic solution to the screw-retained implant restoration: introduction to the implant crown adhesive plug: clinical report.

UNLABELLED: Screw-retained implant crowns may be clinically demanding, especially managing the esthetic and occlusal challenges of screw access channel closure. Many clinicians have moved away from using screw retention as a means of fixing a crown to an implant in favor of cementation to an underlying abutment. A link has been established between peri-implant disease and excess cement extrusion in cement-retained implant restorations. This article describes a novel technique of bonding a pressed porcelain plug into the screw access channel of an implant restoration that allows for control of occlusion, matches the esthetics of a cement-retained crown, and eliminates the issues of excess cement. CLINICAL SIGNIFICANCE: Overcoming the restorative challenges (esthetic, occlusal) of the screw access channel in a screw-retained implant restoration is difficult. By fabricating a pressed ceramic over metal crown and esthetic plug these challenges can be dealt with in a predictable manner.

A descriptive study of the radiographic density of implant restorative cements.

STATEMENT OF PROBLEM: Cementation of implant prostheses is a common practice. Excess cement in the gingival sulcus may harm the periodontal tissues. Identification of the excess cement may be possible with the use of radiographs if the cement has sufficient radiopacity. PURPOSE: The purpose of this study was to compare the radiographic density of different cements used for implant prostheses. MATERIAL AND METHODS: Eight different cements were compared: TempBond Original (TBO), TempBond NE (TBN), Fleck's (FL), Dycal (DY), RelyX Unicem (RXU), RelyX Luting (RXL), Improv (IM), and Premier Implant Cement (PIC). Specimen disks, 2 mm in thickness, were radiographed. Images were made using photostimulable phosphor (PSP) plates with standardized exposure values. The average grey level of the central area of each specimen disk was selected and measured in pixels using a software analysis program, ImageTool, providing an average grey level value representative of radiodensity for each of the 8 cements. The radiodensity was determined using the grey level values of the test materials, which were recorded and compared to a standard aluminum step wedge. An equivalent thickness of aluminum in millimeters was calculated using best straight line fit estimates. To assess contrast effects by varying the exposure settings, a second experiment using 1-mm-thick cement specimens radiographed at both 60 kVp and 70 kVp was conducted. The PSP plates with specimens were measured for a grey level value comparison to the standard aluminum step wedge, using the same software program. RESULTS: The highest grey level values were recorded for the zinc cements (TBO, TBN, and FL), with the 1-mm specimen detectable at both 60- and 70-kVp settings. A lower grey level was recorded for DY, indicative of a lower radiodensity compared to the zinc cements, but higher than RXL and RXU. The implant-specific cements had the lowest grey level values. IM could only be detected in 2-mm-thick sections with a lower aluminum equivalence value than the previously mentioned cements. PIC could not be detected radiographically for either the 1-mm or 2-mm thicknesses at either of the kVp settings. CONCLUSIONS: Some types of cement commonly used for the cementation of implant-supported prostheses have poor radiodensity and may not be detectable following radiographic examination.