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When using dental implants as a treatment modality for tooth replacement, the integration of peri-implant soft tissue is an extremely important consideration. Numerous systemic risk factors for peri-implant disease are known to be... more
When using dental implants as a treatment modality for tooth replacement, the integration of peri-implant soft tissue is an extremely important consideration. Numerous systemic risk factors for peri-implant disease are known to be associated with peri-implant soft tissues. The soft-tissue connection provides a barrier seal directly to the implant or implant abutment and plays a critical role in limiting peri-implant disease. Therefore, clinicicans must take great care in managing the soft tissue. This article discusses three key stages of soft-tissue connection that should be considered when providing dental implant therapy: the healing stage, where cellular adhesion and proliferation are attained; the restorative phase, during which protection is provided to the mature soft-tissue site; and maintenance, a phase where the soft tissue offers revealing information about the health of the implant.
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Implant cantilever beam torque-limiting devices are affected by parallax, which may result in measurement read error. The overread or underread of the true target torque value could lead to premature failure of the screw joint of a dental... more
Implant cantilever beam torque-limiting devices are affected by parallax, which may result in measurement read error. The overread or underread of the true target torque value could lead to premature failure of the screw joint of a dental implant. The purpose of this in vitro study was to determine the effect of the operator's viewing angle relative to the cantilever beam and measurement reading scale when the torque-limiting device is actioned toward or away from the operator. A beam torque wrench (Nobel Biocare USA) was used with the cantilever beam position fixed by using a wedge to read 32 Ncm on the marker arm. It was suspended in a vertical position relative to a digital single-lens reflex camera set at a fixed distance of 48 cm from the marker reading. The camera was rotated in 10-degree increments clockwise and counterclockwise relative to the cantilever beam reading, starting perpendicular to the marker. Photographs were recorded at each angle. Percentage measurement read error was calculated from dimensions of the cantilever beam torque device, including the beam diameter, distance from the marker arm, and the incremental marks on the measurement scale. Data were analyzed descriptively to determine the differences after comparison with the International Organization for Standardization (ISO) 6789-1:2017 recommendations. Photographs compared beam position relative to the 32-Ncm marker. The beam diameter was recorded as 1.5 mm, corresponding to approximately 5 Ncm. The distance between the marker arm and center of the beam was 0.08 mm. Percentage errors were greatest at lower torque values and increased relative to the viewing angle. Photographs showed that instrument overread was most likely to occur as the beam was moved away from the operator, which would result in potential undertightening unless compensated for. Underread was noted when the beam was pulled toward the operator. To prevent measurement read error when using an implant cantilever beam torque-limiting device, the operator should be positioned as close to a perpendicular viewing angle to the cantilever beam as possible. Viewing from an angle greater than 10 degrees from the perpendicular should be avoided for torque values less than 15 Ncm. For screws tightened between 25 Ncm and 35 Ncm, the viewing angle should be less than 30 degrees so that the applied torque is within the maximum deviation of the target torque value set by the ISO 6789-1:2017 recommendations.
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STATEMENT OF PROBLEM The output torque delivered by a dental implant toggle-style torque wrench is known to be affected by activation rate. The International Organization for Standardization (ISO) established the ISO 6789-1 standard to... more
STATEMENT OF PROBLEM The output torque delivered by a dental implant toggle-style torque wrench is known to be affected by activation rate. The International Organization for Standardization (ISO) established the ISO 6789-1 standard to provide guidance on activation rates relative to desired output torque in the Nm torque range. Whether the ISO 6789-1 standard applies at the relatively lower dental torque ranges is not known, and little information is available on the activation rates that clinicians use and how this may affect output torque. PURPOSE The purpose of this in vitro study was to determine how output torque values vary with the activation rates used by clinicians at dental implant-relevant target torque values. MATERIAL AND METHODS To determine clinically relevant activation rates, a new adjustable dental implant toggle-style torque wrench was activated from 0 to 25 Ncm target torque by 5 prosthodontists by using a custom mandibular and maxillary typodont model containing implants and abutments with screws. This provided a baseline of activation rates (mm/sec). Data were transferred to a computerized numerical control model incorporating a variable speed linear motor, which was used to drive a dental implant toggle-style torque wrench attached to an electronic torque measuring device. Constant speed and a regulated dual-speed-assigned 80/20 rate group, where 80% of target torque value was delivered first, then a pause, and the final 20% at different speeds as suggested by the ISO 6789-1 standard, were evaluated. Fast, medium, and slow rates were categorized and applied with target torque values of 10, 25, and 35 Ncm, respectively, for n=12 activations. The output torque values were recorded for both constant and 80/20 groups and compared with the desired target torque values. Data were statistically analyzed with 1-way ANOVA and the Scheffé post hoc paired t test (α=.05). RESULTS The clinicians' activation rates from 0 to 25 Ncm on the typodont model converted into linear speeds resulted in fast =24.19 mm/sec, medium =14.5 mm/sec, and slow =7.25 mm/sec. When actioned at a constant rate, the mean output torque values were generally in the order of slow > medium > fast in activation rates. Generally, precision output torque decreased as target torque increased, especially when slow and medium rates, either constant or regulated 80/20 were used. All mean output torque for slow, medium, and their 80/20 variants were greater than target torque. Fast and 80/20 fast produced the lowest mean output torque values for all torque settings, and at the 35 Ncm setting, the dental implant toggle-style torque wrench output torque mean values were lower than target torque. Statistically significant differences (P<.05) were found among groups, most notably in the 80/20 dual-speed groups, especially in comparisons with the 80/20 fast rate group. When the target torque value was 10 Ncm with the 80/20 fast rate, the output torque value deviated from the maximum ISO limit by more than 6%. CONCLUSIONS The rate of actioning a dental implant toggle-style torque wrench influenced the delivered torque value, with fast rate actioning producing lower and less precise output torque values.
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STATEMENT OF PROBLEM The use of cement-retained implant-supported prostheses is a well-established treatment option. Techniques have been proposed to reduce the amount of residual excess cement (REC) around cement-retained single-implant... more
STATEMENT OF PROBLEM The use of cement-retained implant-supported prostheses is a well-established treatment option. Techniques have been proposed to reduce the amount of residual excess cement (REC) around cement-retained single-implant restorations. However, studies evaluating the effectiveness of such techniques related to cement-retained implant-supported fixed partial dentures (CRISFPDs) are lacking. PURPOSE The purpose of this in vitro study was to evaluate the effectiveness of various cement application techniques for CRISFPDs. MATERIAL AND METHODS Two implant analogs were placed in the lateral incisor sites in a maxillary, 3D printed cast with 4 missing incisors. Twenty standardized, removable, printed soft-tissue replicas, 40 milled titanium custom abutments, and 20 milled zirconia CRISFPDs were fabricated. Two cement application techniques, the brush on technique (BOT), and the polyvinyl siloxane index (PI) technique were compared. Two cementation techniques, without bib (control) (n=10) and with a polytetrafluoroethylene (PTFE) bib (test) (n=10), were used. A premeasured amount of interim cement was used to cement the CRISFPDs. The CRISFPDs were retrieved after cementation, and standardized photographs of 4 quadrants of each abutment-CRISFPD assembly were made by using a software program that is used to calculate the ratio between the area covered with REC and the total specimen area. The extension of the REC on both the abutment and soft-tissue replica was measured at sites before and after cleaning the REC. A generalized linear mixed-model procedure was used for statistical analysis (α=.05). RESULTS For cement application, the polyvinyl siloxane (PVS) index technique had significantly less REC than the brush on technique (P<.05). The use of a PTFE bib led to significantly less REC than when no bib was used (P<.05). CONCLUSIONS The use of the PVS index technique along with a PTFE bib was effective in reducing REC for CRISFPDs.
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STATEMENT OF PROBLEM Implant abutment screw loosening is a common prosthetic complication of implant-supported crowns. However, reports that have objectively evaluated the effectiveness of different tightening protocols on reverse... more
STATEMENT OF PROBLEM Implant abutment screw loosening is a common prosthetic complication of implant-supported crowns. However, reports that have objectively evaluated the effectiveness of different tightening protocols on reverse tightening values are sparse. PURPOSE The purpose of this in vitro study was to determine the optimal tightening protocol for implant abutment screws. MATERIAL AND METHODS Fifty Neoss implants were randomly distributed to 5 groups (n=10). The implants received a cover screw and mounted, and the impression coping was tightened. Tightening was measured by using a digital measuring device. Then, the implant abutments were placed and tightened to 32 Ncm by using a Crystaloc screw. In Group 2T10I, the screws were tightened twice with an interval of 10 minutes between the first and second tightening. In Group 2T0I, the screws were tightened twice with no interval time. In Group 1T, the screws were tightened 1 time only. In Group TCT, the screws were tightened, counter-tightened, and then tightened again. In Group TCTCT, the abutment screws were tightened, counter-tightened, tightened, counter-tightened, and then tightened again. All the mounted implants were left in the same environment for 3 hours, and the reverse tightening values were then measured. RESULTS The mean reverse tightening values of the first 4 groups ranged from 21.49 Ncm to 22.57 Ncm, whereas the reverse tightening value for the fifth group was 25.51 Ncm. A significant difference was found among the groups (P<.05) with reverse tightening data. CONCLUSIONS No significant difference was found in tightening the abutment screw 2 times with a 10-minute interval time, no interval time, or tightening it 1 time only. However, a significant difference was found in reverse tightening in the 3-time tightening and counter-tightening group.
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The aim of implant therapy is integration, not only host tissue integration but also in the form of biology, esthetics, and mechanics, whereby the implant works as a system in harmony with the human body. Research inspired, this chapter... more
The aim of implant therapy is integration, not only host tissue integration but also in the form of biology, esthetics, and mechanics, whereby the implant works as a system in harmony with the human body. Research inspired, this chapter will evaluate the fundamentals of soft tissue integration, the seal that protects the bone and acts as a barrier to the oral environment. Written by practicing clinicians, the goal is to provide information on how to optimize health through understanding handling, cleaning, aesthetics, and mechanics of the restorative componentry.
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Anatomically contoured healing abutments have been shown to contain and protect slow-resorbing substitution grafts, resulting in bone and soft-tissue volume augmentation. Even in healed sites customized healing abutments have demonstrated... more
Anatomically contoured healing abutments have been shown to contain and protect slow-resorbing substitution grafts, resulting in bone and soft-tissue volume augmentation. Even in healed sites customized healing abutments have demonstrated favorable outcomes compared to standard healing abutments. Through two separate cases, this article describes a technique that enables simple chairside fabrication of precisely contoured customized healing abutments and exact 3-dimensional intraoral positioning. With this technique, the soft tissues upon maturation closely resemble the natural root contour, which allows for the generation of esthetic and functional implant-supported restorations.
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Due to their exceptional biological and mechanical properties, titanium and its alloys are commonly used in both dental implants and implant abutments, upon which prostheses can be attached. The gray color of titanium metal, however, can... more
Due to their exceptional biological and mechanical properties, titanium and its alloys are commonly used in both dental implants and implant abutments, upon which prostheses can be attached. The gray color of titanium metal, however, can elicit esthetic problems, as it has the potential to show through a translucent ceramic restorative material. Various solutions have been proposed and used to attempt to overcome esthetic issues associated with titanium. This article describes a simple, economical technique to color titanium abutments and components utilizing anodization, resulting in light reflection and color enhancement through a natural physics phenomenon known as light interference patterns. A technique for improving the bonding capabilities of cement to the abutment is also discussed.
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ABSTRACT
As cemented implant restorations have grown in popularity, so has the incidence of peri-implant disease. The association between implant restorations, cement, and this disease, however, remains somewhat unclear. This article examines... more
As cemented implant restorations have grown in popularity, so has the incidence of peri-implant disease. The association between implant restorations, cement, and this disease, however, remains somewhat unclear. This article examines factors that may contribute to peri-implant disease, including biology, implant depth, restoration depth, and implant material properties, and considers potential causes of the disease involving residual cement. Guidance on how to prevent this problem from occurring is provided.
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The esthetic challenges of using all-titanium alloy abutments have led to the increasing use of prefabricated titanium inserts bonded to tooth-colored abutments and fixed dental prostheses. Optimal bonding protocols related to the... more
The esthetic challenges of using all-titanium alloy abutments have led to the increasing use of prefabricated titanium inserts bonded to tooth-colored abutments and fixed dental prostheses. Optimal bonding protocols related to the titanium alloy treatment have not been established. The purpose of this in vitro study was to evaluate the effects of different surface treatments and cementation procedure combinations of titanium-6aluminum-4vanadium alloy (Ti6Al4V) disks on the bond strength of lithium disilicate glass-ceramics. A total of 100 computer-aided designed and computer-aided manufacturing (CAD-CAM) Ti6Al4V disks (4×6.6 mm) were used. As-milled specimens, without surface treatment, were used as controls. Surface treatment variables including alumina airborne-particle abrasion (50 μm, 0.4 MPa, 10 seconds, at 20-mm distance), ceramic etchant gels (5% and 9.5%), and buffered hydrofluoric (HF) acid etching, and etching times (30 and 90 seconds) were assessed. Heat-pressed lithium d...
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A technique is described which will generate a customized healing abutment for a dental implant to allow the development of ideal soft tissue contours. With implant position and soft tissue contours defined at surgery, customized... more
A technique is described which will generate a customized healing abutment for a dental implant to allow the development of ideal soft tissue contours. With implant position and soft tissue contours defined at surgery, customized impression techniques can be used to capture those details and help generate the definitive implant-supported restoration. This workflow reduces the number of patient visits.
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Colorizing titanium alloys by electrochemical anodization is used in dentistry especially for identification purposes. Colorization is the result of distinct voltage applications to specific titanium alloys when placed in an electrolyte.... more
Colorizing titanium alloys by electrochemical anodization is used in dentistry especially for identification purposes. Colorization is the result of distinct voltage applications to specific titanium alloys when placed in an electrolyte. Titanium and titanium alloys differ in their ability to be anodized. As titanium-6aluminum-4vanadium is commonly used as an abutment material, we have developed a specific color reference scale relating color to the voltage applied.
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Dental cements for cement-retained restorations are often chosen based on clinician preference for the product's material properties, mixing process, delivery mechanism, or viscosity. The composition of dental cement may play a... more
Dental cements for cement-retained restorations are often chosen based on clinician preference for the product's material properties, mixing process, delivery mechanism, or viscosity. The composition of dental cement may play a significant role in the proliferation or inhibition of different bacterial strains associated with periimplant disease, and the effect of dental cements on host cellular proliferation may provide further insight into appropriate cement material selection. The purpose of this in vitro study was to investigate the cellular host response of bone cells (osteoblasts) and soft tissue cells (gingival fibroblasts) to dental cements. Zinc oxide (eugenol and noneugenol), zinc phosphate, and acrylic resin cements were molded into pellets and directly applied to confluent preosteoblast (cell line MC3T3 E1) or gingival fibroblast cell cultures (cell line HGF) to determine cellular viability after exposure. Controls were defined as confluent cell cultures with no cemen...
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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... more
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.
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The usefulness of IOR has been described along with its limitations when considering implant restorations. One major issue is the alignment of the incident x-rays so that they are consistently perpendicular to the implant body, to provide... more
The usefulness of IOR has been described along with its limitations when considering implant restorations. One major issue is the alignment of the incident x-rays so that they are consistently perpendicular to the implant body, to provide the most reliable information possible. Other limitations include inconsistencies as a result of the inability to verify the nature and extent of bone around an implant, which is subject to variation as a result of type of bone and site. Where implants are concerned, as a diagnostic tool IOR should be considered as part of a multitude of tests-including probing, mobility, symptoms, and other soft-tissue evaluations. It must be emphasized that IOR cannot be relied upon as being the sole diagnostic test.
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An immediate restorative technique resolving the acute problem of traumatic tooth fracture with pulpal and periodontal involvement, in which the fragment(s) are re-alignable. Repositioning facilitated by a custom stent, using... more
An immediate restorative technique resolving the acute problem of traumatic tooth fracture with pulpal and periodontal involvement, in which the fragment(s) are re-alignable. Repositioning facilitated by a custom stent, using dentine/enamel bonding. A challenging, conservative and economically viable procedure within the compass of a single visit.
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Considered to be an excellent treatment option for the replacement of lost or missing teeth, dental implants can dramatically improve a patient's quality of life. Patient selection, clinical skill, and maintenance are all factors that... more
Considered to be an excellent treatment option for the replacement of lost or missing teeth, dental implants can dramatically improve a patient's quality of life. Patient selection, clinical skill, and maintenance are all factors that can significantly affect outcome. This case report highlights problems encountered in what many would consider to be a straightforward case: extraction of a fractured root, implant placement, and restoration in an otherwise dentally and medically fit and healthy patient. The report exposes some of the issues that could potentially result in what could be deemed an implant catastrophe and then explores possible treatment options to help rectify the failures. Finally, the authors describe the treatment provided--a periodontal-prosthodontic solution--and report on the 4-year post-treatment follow-up.
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A link has been established between peri-implant disease and excess cement extrusion in cement-retained implant restorations. The histologic findings of two patients with failed implants secondary to residual excess cement are reported... more
A link has been established between peri-implant disease and excess cement extrusion in cement-retained implant restorations. The histologic findings of two patients with failed implants secondary to residual excess cement are reported here. If excess cement is detected early and adequately removed, resolution can occur in the majority of situations. Simple recommendations are proposed, with the intention of preventing further implant failures from residual excess cement.
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Dentistry, Dental Implants, Humans, Female, Male, and 5 moreMandible, Middle Aged, Adult, Crowns, and Peri-implantitis
OBJECTIVE: To microbiologically evaluate the efficacy of cotton and polytetrafluoroethylene (PTFE) tape used as spacer materials.METHOD AND MATERIALS: Twenty-six extracted human molars were restored using either cotton or PTFE tape as... more
OBJECTIVE: To microbiologically evaluate the efficacy of cotton and polytetrafluoroethylene (PTFE) tape used as spacer materials.METHOD AND MATERIALS: Twenty-six extracted human molars were restored using either cotton or PTFE tape as spacers under a standardized provisional restorative material (Cavit). The teeth were incubated for 7 days in a culture of Streptococcus gordonii or in liquid media alone. The spacers were removed and tested for bacterial contamination. The access cavities were also evaluated for bacterial contamination.RESULTS: Nine of 10 teeth with cotton spacers and one of 10 teeth with PTFE spacers were positive for S gordonii growth. The nine teeth in the cotton group also showed contamination of the access cavities.CONCLUSION: Even under optimal conditions, cotton spacers may cause leakage into the access cavities. Cotton fibers may serve as a route for bacterial contamination of the access cavities and root canal space. In contrast, PTFE tape did not provide an avenue for bacterial contamination.
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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... more
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.
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... Solutions Authored by Chandur PK Wadhwani, DDS, MSD, and Alfonso F. Piñeyro, DDS ... Radiographic results: Three of the 8 disks can be detected. The common feature with these cements is they all contain zinc (TempBond [Kerr], TempBond... more
... Solutions Authored by Chandur PK Wadhwani, DDS, MSD, and Alfonso F. Piñeyro, DDS ... Radiographic results: Three of the 8 disks can be detected. The common feature with these cements is they all contain zinc (TempBond [Kerr], TempBond NE [Kerr], Flecks [Mizzy]). b a a ...
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Presence of metal ions and debris resulting from corrosion processes of dental implants in vivo can elicit adverse tissue reactions, possibly leading to peri-implant bone loss and eventually implant failure. This study hypothesized that... more
Presence of metal ions and debris resulting from corrosion processes of dental implants in vivo can elicit adverse tissue reactions, possibly leading to peri-implant bone loss and eventually implant failure. This study hypothesized that the synergistic effects of bacterial biofilm and micromotion can cause corrosion of dental implants and release of metal ions in-vivo. The goal is to simulate the oral environment where an implant will be exposed to a combination of acidic electrochemical environment and mechanical forces. Four conditions were developed to understand the individual and synergistic effects of mechanical forces and bacterial biofilm on the surface of dental implants. In condition 1, it was found that torsional forces during surgical insertion did not generate wear particle debris or metal ions. In condition 2, fatigue tests were performed in a wet environment to evaluate the effect of cyclic occlusal forces. The mechanical forces applied on the implants were able to ca...
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Reuse or &amp;amp;amp;amp;amp;amp;quot;recycle&amp;amp;amp;amp;amp;amp;quot; of dental implant healing abutments in clinical practice is common, primarily for economic rational. To determine if this practice results in reuse of... more
Reuse or &amp;amp;amp;amp;amp;amp;quot;recycle&amp;amp;amp;amp;amp;amp;quot; of dental implant healing abutments in clinical practice is common, primarily for economic rational. To determine if this practice results in reuse of components that carry with them some degree of contamination between patients, even following thorough cleaning and sterilization. One hundred healing abutments were collected from eight dental clinics following patient use. The abutments were cleaned and sterilized prior to collection. The samples were treated with a protein-specific stain (Phloxine B), and photographed. Ninety-nine percent of the abutments showed residual protein contamination at one or more sites following cleaning and sterilization. Reuse of healing abutments between patients should be reevaluated in light of this data.
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The most appropriate luting agent for restoring cement-retained implant restorations has yet to be determined. Leachable chemicals from some types of cement designed for teeth may affect metal surfaces. The purpose of this in vitro study... more
The most appropriate luting agent for restoring cement-retained implant restorations has yet to be determined. Leachable chemicals from some types of cement designed for teeth may affect metal surfaces. The purpose of this in vitro study was to evaluate the shear bond strength and interactions of machined titanium-based alloy with dental luting agents. Eight dental luting agents representative of 4 different compositional classes (resin, polycarboxylate, glass ionomer, and zinc oxide-based cements) were used to evaluate their effect on machined titanium-6 aluminum-4 vanadium (Ti-6Al-4V) alloy surfaces. Ninety-six paired disks were cemented together (n=12). After incubation in a 37°C water bath for 7 days, the shear bond strength was measured with a universal testing machine (Instron) and a custom fixture with a crosshead speed of 5 mm/min. Differences were analyzed statistically with 1-way ANOVA and Tukey HSD tests (α=.05). The debonded surfaces of the Ti alloy disks were examined under a light microscope at ×10 magnification to record the failure pattern, and the representative specimens were observed under a scanning electron microscope. The mean ±SD of shear failure loads ranged from 3.4 ±0.5 to 15.2 ±2.6 MPa. The retention provided by both polycarboxylate cements was significantly greater than that of all other groups (P&amp;amp;amp;amp;amp;amp;lt;.05). The scanning electron microscope examination revealed surface pits only on the bonded surface cemented with the polycarboxylate cements. Cementation with polycarboxylate cement obtained higher shear bond strength. Some chemical interactions occurred between the machined Ti-6Al-4V alloy surface and polycarboxylate cements during cementation.