Dentists' Perspective and Experiences Relative to the Accidental Dropping of Implant Drivers and Components Intraorally: A Survey of Practicing Clinicians.

Ingestion or aspiration of dental implant screwdrivers or implant components is potentially life-threatening. There are no reports on the frequency at which dentists drop these devices within the mouth or which components are most problematic. There are few reports on what protective measures clinicians take, where risks exist, and how this problem is managed. A 9-part questionnaire was provided to dentists. Data collected included clinicians' roles, implant surgeons, restorative clinicians, or both-the frequency of dropping implant screwdrivers or components, items considered most problematic. Patient protection and management were also requested. Finally, questions related to how much of a problem clinicians considered this to be and if further solutions and a standardized management protocol should be developed. One hundred twelve dentists voluntarily completed the survey. Of the dentists, 54% restored, 37% restored and surgically placed, and 9% solely placed implants. Twenty-nine percent claimed never to drop components, with 56% dropping an instrument less than 10% of the time. Less than half would suggest patients seek medical advice if a screwdriver or component was accidentally dropped intraorally and was not recovered. Thirty percent never tied floss tethers to screwdrivers, and a similar percentage reported they only sometimes did so. Throat pack protection was reported 51% of the time. Ninety percent considered dropping components an issue, with screwdrivers most problematic. Aspiration or ingestion of implant screwdrivers and components is problematic, with dentists varying their use of protection devices. There is a need to standardize and implement patient protection procedures and management and develop methods to reduce the risk of these potentially life-threatening issues.

Clinician preferences for single-unit implant restoration designs and materials: A survey of the membership of the Pacific Coast Society for Prosthodontics.

STATEMENT OF PROBLEM: Clinical research has difficulty keeping pace with the rapid evolution of materials, protocols, and designs of single-unit implant restorations. The clinical design preferences of prosthodontics for different clinical scenarios are lacking. PURPOSE: The purpose of this cross-sectional survey was to determine the current prevalence of usage of various treatment options and materials for single-unit implant-supported restorations. MATERIAL AND METHODS: From August to September of 2022, a survey invitation was sent to members of the Pacific Coast Society for Prosthodontics (PCSP). The survey was hosted online and asked 37 questions related to the materials, protocols, and design preferences for single-unit implant-supported restorations in various clinical scenarios. The prompts included the suggestion that answers should be based on preferences for the "ideal" treatment of a hypothetical patient seeking implant treatment for the replacement of a single missing tooth. RESULTS: Of 133 questionnaires sent via email, 35 were returned. The results are presented with histograms that use color coding as an experience proxy metric. A total of 87% of respondents was in private practice, and 60% reported having restored more than 1000 single-unit implant restorations. For the replacement of a single maxillary central incisor under ideal conditions and angulation through the palatal surface, respondents preferred bone level implants (93%) and screw-retained restorations (80%), with 50% of those being zirconia with a titanium abutment and 21% being cast metal-ceramic. For an identical scenario, except that the angulation would be through the facial surface, respondents preferred the angled screw system (55%) and cemented (41%) restorations. For the replacement of a single missing mandibular molar under ideal conditions, respondents preferred bone level implants (79%) and screw-retained restorations (79%), with 70% of those being zirconia with a titanium abutment and 17% being cast metal-ceramic. CONCLUSIONS: While a wide range of protocols, designs, and materials exist for the replacement of a single missing tooth, these results provide a snapshot of current single-unit implant prosthodontic preferences in the Western United States and Canada.

Survival analysis of zirconia implant-supported, fixed complete dentures: A 5-year retrospective cohort study.

STATEMENT OF PROBLEM: Existing data on the mid-term to long-term survival rates of zirconia implant-supported, fixed complete dentures (Zir-IFCDs) are lacking. PURPOSE: The purpose of this retrospective clinical study was to assess the prosthetic survival rate in patients treated with Zir-IFCDs. MATERIAL AND METHODS: The patient record system at the Dental College of Georgia (DCG), Augusta University was searched to identify all patients treated with Zir-IFCDs from 2015 through 2022 by the DCG graduate prosthodontic, general practice residency, and Advanced Education in General Dentistry (AEGD) programs. Reasons for replacement were grouped as failure of veneering porcelain, framework fracture, implant loss, patient-driven concerns, excessive occlusal wear, and other. RESULTS: A total of 67 arches were found that met the inclusion criteria, 46 maxillary and 21 mandibular. The median follow-up time was 8.5 months (interquartile range, 2.7 to 30.9 months). A total of 9 of the 67 arches were identified as having failed (4 maxillary, 5 mandibular), requiring replacement. Reasons for failure were as follows: 3 framework fractures, 2 implant losses, 2 patient-related concerns, 1 fracture of veneering porcelain, and 1 unknown. The combined survival rate (Kaplan-Meier, log-normal modeling) for Zir-IFCDs was 88.8% at 1 year and 72.5% at 5 years CONCLUSIONS: Based on the findings, the Zir-IFCDs investigated had a survival rate lower than that reported in similar studies, though higher than published results for metal-acrylic resin-IFCDs. The most common source of failure was fracture of the zirconia framework. Thickness of the zirconia framework, interocclusal space, cantilever length, occlusal force, and status of the opposing dentition may have been associated with framework failures and should be investigated further.

Effect of activation rate on output torque values from a dental implant toggle-style torque wrench.

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.

Changes in Peri-implant Marginal Bone Level by Jaw Location: A Systematic Review and Meta-Analysis of 4970 Implants.

The purpose of this study was to evaluate the current evidence on marginal bone-level changes (ΔMBL) around internal connection implants with fixed prostheses by jaw location over time. An electronic literature search for ΔMBL (change in marginal bone level) was conducted in 6 databases. The data from the included manuscripts were categorized by jaw sextant of the implants and duration of follow-up (<2 years, 2-5 years, and >5 years). Meta-analyses were performed on groups with at least 5 studies. A total of 1270 records were screened. Full-text review of 413 papers resulted in a total of 46 studies (representing 2259 patients with 4970 implants) included for quantitative synthesis and analysis. The ΔMBL was summarized at 2 time intervals with the following results: <2 years (anterior maxilla = 0.393 mm [95% confidence interval {CI}, 0.172, 0.613], posterior maxilla = 0.468 mm [95% CI, 0.288, 0.648], and posterior mandible 0.559 mm [95% CI, 0.397, 0.72]), 2 to 5 years (anterior maxilla = 0.683 mm [95% CI, 0.224, 1.142], posterior maxilla = 0.645 mm [95% CI, 0.42, 0.87], and posterior mandible 0.563 mm [95% CI, 0.278, 0.849]). There were insufficient studies in the anterior mandible and with follow-up data over 5 years for quantitative synthesis. Within the limitations of this study, location within the maxillary and mandibular jaws does not seem to influence ΔMBL around internal connection bone level implants with fixed restorations. Although there may be a tendency for greater initial remodeling in the posterior mandible followed by long-term stability, additional studies are needed to evaluate this further.

Evaluation of implant abutment screw tightening protocols on reverse tightening values: An in vitro study.

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.

Clinician preferences for complete-arch fixed implant-supported prostheses: A survey of the membership of the Pacific Coast Society for Prosthodontics.

STATEMENT OF PROBLEM: Current in vivo and in vitro research has difficulty keeping pace with the rapid evolution of materials, protocols, and designs of the complete-arch fixed implant-supported prosthesis. PURPOSE: The purpose of this survey was to determine the current prevalence of usage of various treatment modalities and materials for complete-arch fixed implant-supported prostheses. MATERIAL AND METHODS: From November to December of 2018, a survey invitation was sent out to members of the Pacific Coast Society for Prosthodontics (PCSP). The survey was hosted online, and asked a series of 18 questions related to the materials, protocols, and design preferences for complete-arch fixed implant-supported prostheses. The prompt included the suggestion that answers should be based on preferences for ideal treatment of a hypothetical completely edentulous patient seeking fixed, implant-supported prostheses, assuming sufficient native bone and an opposing complete-arch fixed implant-supported prosthesis. RESULTS: Of 133 invitations sent via email, 45 (34%) surveys were started and 48 (36%) were completed. Pertinent results are summarized in histograms with color coding in each answer group to indicate the total number of arches the person had treated (a proxy for experience). Most respondents were in private practice (73%) and had completed more than 21 arches of fixed implant-supported prostheses (62%). Nearly half (49%) of the respondents preferred 6 implants in the maxilla, while the preferred number in the mandible was highly varied between 4 (33%), 5 (27%), and 6 (29%) implants. Three-fourths (75%) preferred bone-level implant designs, and the plurality was ambivalent on the use of a platform-switched design (48%). Two-thirds (67%) preferred to deliver a complete-arch fixed provisional prosthesis at the time of surgery. Two-thirds (67%) preferred to make the definitive impression by using rigidly splinted, open-tray copings. While most (67%) preferred to fabricate the definitive maxillary and mandibular prostheses with identical occlusal materials, the specifics of material selection between arches varied greatly. In the maxilla, a plurality preferred anatomic contour zirconia with titanium bases (33%). In the mandible, a plurality preferred laboratory-processed resin with denture teeth over a milled metal bar (32%). CONCLUSIONS: While a wide range of protocols, designs, and materials exist in the use of the complete-arch fixed implant-supported prosthesis, these results provide a snapshot of current clinical preferences in the Western United States.

Treatment of peri-implant recession with a screw-retained, interim implant restoration: A clinical report.

This clinical report describes a patient with an osseointegrated implant and definitive restoration of the maxillary right lateral incisor who was seeking resolution of the recession of the peri-implant tissues which revealed the underlying zirconia abutment. The patient had previously received a connective tissue graft in an unsuccessful attempt to resolve the recession. An undercontoured interim restoration that allowed for soft tissue coronal migration resolved the soft tissue deficiency.

The hemi-engaging fixed dental implant prosthesis: A technique for improved stability and handling.

Clinicians commonly contend that the screw-retained, implant-supported fixed dental prosthesis (FDP) should be fabricated with all nonengaging abutments to allow for the inherent nonparallelism of the implants and the inability of the abutment connections to draw together during insertion and removal. The problem with a fully nonengaging FDP is difficulty in handling and more strain on the abutment screws, ultimately leading to increased rates of breakage and loosening. The hemi-engaging FDP design regains much of the advantage afforded by the internal connection and improves prosthetic handing both clinically and in the laboratory. The benefits of this technique are best seen for short-span (fewer than 5 units), screw-retained, implant-supported FDPs.

Residual Debris within Internal Features of As-received New Dental Implants.

PURPOSE: To investigate residual debris within internal features of new "as received" dental implants. MATERIALS AND METHODS: A total of 15 new dental implants representing various dental implant brands were obtained in sealed containers from the manufacturers. Batch numbers and implant types were documented. In a controlled setting, implants were carefully unpacked, and their internal aspects were visually examined. Further analysis involved light microscopy imaging to document and photograph any foreign material. The internal aspect of the implants were sampled with both an endodontic paper cone and a fine bristle brush swab. These were inserted into the implant, rotated three times, then removed and examined under a microscope at 30x magnification. Post sampling some of the brushes/swabs were washed with alcohol to remove debris that could be further examined under magnification. RESULTS: Inspection of the implants without magnification revealed no visible foreign materials. However, under light microscopy (x10 and x30), all 15 implants exhibited small black particles at various internal sites, including connections, threads, and deep within screw channels. Swabs evaluated at magnification detected what appeared to be metal particles in all 15 implants, ranging from distinct metal shards to smaller particles. CONCLUSION: This study suggests that implant manufacturers have not effectively removed all machining debris from within implant bodies, potentially producing prosthetic and clinical complications.

Abutment emergence modification for immediate implant provisional restorations.

UNLABELLED: In their stock form, some titanium provisional implant abutments are not ideally designed for use in immediate placement/immediate provisional restoration treatment. This is largely due to the apical flare design that applies excessive pressure to the peri-implant soft tissue complex and crestal bone. This appears to have the undesirable effect of increasing peri-implant bone resorption and severely impeding the potential for increases in gingival volume. This type of stock titanium abutment will therefore benefit significantly from recontouring. The subgingival portion of the abutment is recontoured from the flared stock shape to a straight or parallel design. This modification minimizes pressure on the surgical site and provides additional space around the subgingival portion of the provisional restoration, within which the gingiva has the potential to remodel and fill. This allows the potential formation of additional peri-implant gingival volume and a coronal maintenance or migration of the soft tissue complex. In order to minimize the "graying effect" of titanium abutments, the retentive portion is opaqued by the technician or clinician. These modifications will improve the potential outcomes for both the peri-implant gingiva and the provisional restoration. CLINICAL SIGNIFICANCE: Narrowing the emergence profile of implant abutments for use in immediate implant provisional restorations appears to allow for creation of greater peri-implant volume. Thus resulting in increased esthetic potential and predictability of the peri-implant gingiva.

Prosthetic soft tissue management following two periimplant graft failures: a clinical report.

A 53-year-old man experienced 2 soft tissue graft failures resulting in sizable hard and soft tissue defects in the esthetic zone following implant placement. A third connective tissue graft surgery was successful in repairing the defect and significantly improving soft tissue quality. A screw-retained, interim implant prosthesis was instrumental in gradually shaping the soft tissue over the course of the 3 surgeries. The interim prosthesis was modified numerous times to achieve a balance of esthetics, surgical protection, and gingival contours. The initial form of the prosthesis was designed to protect the surgical site and allow space for postsurgical edema. In its final form, the tissue side of the interim prosthesis pontic was designed to mimic the cross-sectional profile of a natural central incisor root but modified to deliver gentle pressure until maximum papilla height was achieved. The definitive restoration was fabricated to mimic the final design of the interim restoration and gingival architecture.

Immediate implant-supported provisional restoration with a root-form pontic for the replacement of two adjacent anterior maxillary teeth: A clinical report.

In implant therapy, the replacement of 2 adjacent maxillary anterior teeth presents several unique challenges: mesiodistal space constraints, the need to maintain or create natural gingival esthetics, the need for esthetic provisional restorations, and the management of nonaxial forces. The treatment presented addresses these challenges through the use of an immediately placed single implant at the central incisor position with a central to lateral incisor cantilever prosthesis in both the immediate provisional and definitive restorations. The provisional restoration was designed to minimize pressure on the surgical site, optimize space for the gingival tissues, and control occlusal loading of the implant during the initial stages of osseointegration. The pontic was modified to replicate the subgingival root anatomy and enhance the gingival esthetic outcome.

Clinical Performance of 11,646 Dental Implants Using Surgical Guides and Two Different Surgical Approaches: A Systematic Review and Meta-analysis.

Purpose: To assess and quantify survival rates and marginal bone levels (MBLs) of implants placed using guided surgery with a flapless approach vs traditional flap elevation. Materials and Methods: An electronic literature search was conducted in PubMed and the Cochrane Library and refereed by two independent reviewers. Data were synthesized for MBL and survival rates for "flapless" vs traditional "flap" implant placement approach groups. Meta-analyses and nonparametric tests for differences between groups were performed. Rates and types of complications were compiled. The study was conducted under PRISMA 2020 guidelines. Results: A total of 868 records were screened. Full-text review of 109 articles resulted in a total of 57 included studies (50 included for quantitative synthesis and analysis). The survival rate was 97.4% (95% CI: 96.7%, 98.1%) for the flapless approach vs 95.8% (95% CI: 93.3%, 98.2%) for the flap approach; weighted Wilcoxon rank sum test for significance was P = .2339. MBL for the flapless approach was 0.96 mm (95% CI: 0.754, 1.16) vs 0.49 mm (95% CI: 0.30, 0.68) for the flap approach; weighted Wilcoxon rank sum test for significance was P = .0495. Conclusion: The outcomes of this review have suggested that surgical guided implant placement can be used as a reliable method regardless of approach. Additionally, flap and flapless approaches provided similar implant survival rates, but the flap technique provided a slightly better MBL than the flapless approach.

Guided and Navigation Implant Surgery: A Systematic Review.

Purpose: To evaluate how guided and navigation surgical approaches for implant placement affect survival and accuracy. Materials and Methods: An electronic literature search was conducted in PubMed/Medline and the Cochrane Library. The reviews were refereed by two independent investigators using the following PICO question: population-patients with missing maxillary or mandibular teeth; intervention-dental implant guided surgery, dental implant navigation surgery; comparison-conventional implant surgery or historical control; outcome-implant survival, implant accuracy. Single-arm, weighted meta-analyses were performed on navigational and static guided surgery groups for cumulative survival rate and accuracy of implant placement (ie, angular, depth, and horizontal deviation). Group metrics with less than five reports were not synthesized. The study was compiled under PRISMA 2020 guidelines. Results: A total of 3,930 articles were screened. Full-text review of 93 articles resulted in a total of 56 articles included for quantitative synthesis and analysis. Implant placement with a fully guided approach resulted in the following means and 95% CI: cumulative survival rate of 97% (96%, 98%), angular deviation of 3.8 degrees (3.4 degrees, 4.2 degrees), depth deviation of 0.5 mm (0.4 mm, 0.6 mm), and horizontal deviation at the implant neck of 1.2 mm (1.0 mm, 1.3 mm). Implant placement with a navigation approach resulted in an angular deviation of 3.4 degrees (3.0 degrees, 3.9 degrees), horizontal deviation at the implant neck of 0.9 mm (0.8 mm, 1.0 mm), and horizontal deviation at the implant apex of 1.2 mm (0.8 mm, 1.5 mm). Conclusion: Static guided and navigation surgical approaches for dental implant placement have survival rates comparable to historical controls. Accuracy of implant placement does not differ markedly between these two approaches.

Implant-Abutment Connections and Their Effect on Implant Survival Rates and Changes in Marginal Bone Levels (Δ): A Systematic Review and Meta-Analysis of 45,347 Oral Implants.

Purpose: To quantify the cumulative oral implant survival rates and changes in radiographic bone levels based on the configuration of the implant-abutment connection type over time. Materials and Methods: An electronic literature search was conducted in four databases (PubMed/MEDLINE, Cochrane Library, Web of Science, and Embase), and records were refereed by two independent reviewers based on the inclusion criteria. Data from included articles were grouped by implant-abutment connection type into four categories ([1] external hex; [2] bone level, internal, narrow cone < 45 degrees; [3] bone level, internal wide cone ≥ 45 degrees or flat; and [4] tissue level) and duration of follow-up (short-term 1 to 2 years, mid-term 2 to 5 years, and long-term > 5 years). Meta-analyses were performed for cumulative survival rate (CSR) and changes in marginal bone level (ΔMBL) from baseline (loading) to last reported follow-up. Studies were split or merged as appropriate based on the implants and follow-up duration in the study and trial design. The study was compiled under PRISMA 2020 guidelines and registered in the PROSPERO database. Results: A total of 3,082 articles were screened. Full-text review of 465 articles resulted in a total of 270 articles (representing 16,448 subjects with 45,347 implants) included for quantitative synthesis and analysis. Mean ΔMBL (95% CI) was as follows: short-term external hex = 0.68 mm (0.57, 0.79); short-term bone level, internal, narrow cone < 45 degrees = 0.34 mm (0.25, 0.43); short-term bone level, internal wide cone ≥ 45 degrees = 0.63 mm (0.52, 0.74); short-term tissue level = 0.42 mm (0.27, 0.56); mid-term external hex = 1.03 mm (0.72, 1.34); mid-term bone level, internal, narrow cone < 45 degrees = 0.45 mm (0.34, 0.56); mid-term bone level, internal wide cone ≥ 45 degrees = 0.73 mm (0.58, 0.88); mid-term tissue level = 0.4 mm (0.21, 0.61); long-term external hex = 0.98 mm, 0.70, 1.25); long-term bone level, internal, narrow cone < 45 degrees = 0.44 mm (0.31, 0.57); long-term bone level, internal wide cone ≥ 45 degrees = 0.95 mm (0.68, 1.22); and long-term tissue level = 0.43 mm (0.24, 0.61). CSRs (95% CI) were: short-term external hex = 97% (96%, 98%); short-term bone level, internal, narrow cone < 45 degrees = 99% (99%, 99%); short-term bone level, internal wide cone ≥ 45 degrees = 98% (98%, 99%); short-term tissue level = 99% (98%, 100%); mid-term external hex = 97% (96%, 98%); mid-term bone level, internal, narrow cone < 45 degrees = 98% (98%, 99%); mid-term bone level, internal wide cone ≥ 45 degrees = 99% (98%, 99%); mid-term tissue level = 98% (97%, 99%); long-term external hex = 96% (95%, 98%); long-term bone level, internal, narrow cone < 45 degrees = 98% (98%, 99%); long-term bone level, internal wide cone ≥ 45 degrees = 99% (98%, 100%); and long-term tissue level = 99% (98%, 100%). Conclusion: The configuration of the implant-abutment interface has a measurable effect on the ΔMBL over time. These changes can be observed over a period of at least 3 to 5 years. At all measured time intervals, similar ΔMBL was noted for external hex and internal wide cone ≥ 45-degree connections, as were internal, narrow cone < 45-degree and tissue-level connections.

Ceramic Dental Implants: A Systematic Review and Meta-analysis.

Purpose: To evaluate the performance of one- and two-piece ceramic implants regarding implant survival and success and patient satisfaction. Materials and Methods: This review followed the PRISMA 2020 guidelines using PICO format and analyzed clinical studies of partially or completely edentulous patients. The electronic search was conducted in PubMed/MEDLINE using Medical Subject Headings (MeSH) keywords related to dental zirconia ceramic implants, and 1,029 records were received for detailed screening. The data obtained from the literature were analyzed by single-arm, weighted meta-analyses using a random-effects model. Forest plots were used to synthesize pooled means and 95% CI for the change in marginal bone level (MBL) for short-term (1 year), mid-term (2 to 5 years), and long-term (over 5 years) follow-up time intervals. Results: Among the 155 included studies, the case reports, review articles, and preclinical studies were analyzed for background information. A meta-analysis was performed for 11 studies for one-piece implants. The results indicated that the MBL change after 1 year was 0.94 ± 0.11 mm, with a lower bound of 0.72 and an upper bound of 1.16. For the mid term, the MBL was 1.2 ± 0.14 mm with a lower bound of 0.92 and an upper bound of 1.48. For the long term, the MBL change was 1.24 ± 0.16 mm with a lower bound of 0.92 and an upper bound of 1.56. Conclusion: Based on this literature review, one-piece ceramic implants achieve osseointegration similar to titanium implants, with a stable MBL or a slight bone gain after an individual initial design depending on crestal remodeling. The risk of implant fracture is low for current commercially available implants. Immediate loading or temporization of the implants does not interfere with the course of osseointegration. Scientific evidence for two-piece implants is rare.

Mandibular Flexure and Its Significance: An In Vivo Cone Beam-Computed Tomography Proof-of-Concept Study.

The aim of this study was to assess intra-arch mandibular dimensional changes that may occur during mouth opening using cone beam-computed tomography (CBCT). Fifteen patients in need of any type of treatment whose execution considered a pre- and post-CBCT assessment consented and were enrolled. CBCTs were taken with the following settings: 90 kV, 8 mA, field of view (FOV) 140 by 100 mm (height and diameter), Voxel size 0.25 mm (high resolution). The pre-CBCT was executed in the maximum mandibular opening (MO), while the post-CBCT was in the maximum intercuspation (MI). A thermoplastic stent with radiopaque fiducial markers (steel ball bearings) was fabricated for each patient. Measurements were made using radiographic markers between contralateral canines and contralateral first molars and between ipsilateral canines and first molars on both sides. Paired t-tests were performed to evaluate the difference between open and closed positions on these four measurements. In the MO position were registered a significative tightening of the mandible at the canine (-0.49 mm, SD 0.54 mm; p < 0.001) and molar points (-0.81 mm, SD 0.63 mm; p < 0.001) and a significative shortening of the mandible on the right (-0.84 mm, SD 0.80 mm; p < 0.001) and left sides (-0.87 mm, SD 0.49 mm; p < 0.001). Within the study limitations, mandibular flexure determined a significant shortening and tightening between maximum intercuspation to maximum opening positions. Mandibular dimensional changes should be considered in light of other patient factors in the treatment planning of implant positioning and long-span complete arch implant-supported fixed prostheses in order to avoid technical complications.

Direct custom implant impression copings for the preservation of the pontic receptor site architecture.

The direct custom implant impression coping technique is designed to record the periimplant gingiva and pontic receptor site after the tissues have been shaped with a provisional restoration. The technique prevents inaccurate recording of the gingival architecture by using a dual polymerizing composite resin placed into the sulcus and pontic receptor sites and adapted to the open tray implant impression copings. This technique may improve soft tissue accuracy between the clinical condition and the laboratory cast.

Reverse spot bonding: a novel technique for provisionalization with immediate dentin sealing.

Described here is a clinical technique for the creation of predictable, stable, and efficient provisionals in combination with the use of immediate dentin sealing for partial-coverage posterior ceramic restorations.