Dynamic analyses of a soft tissue-implant interface: Biological responses to immediate versus delayed dental implants.

AIM: To qualitatively and quantitatively evaluate the formation and maturation of peri-implant soft tissues around 'immediate' and 'delayed' implants. MATERIALS AND METHODS: Miniaturized titanium implants were placed in either maxillary first molar (mxM1) fresh extraction sockets or healed mxM1 sites in mice. Peri-implant soft tissues were evaluated at multiple timepoints to assess the molecular mechanisms of attachment and the efficacy of the soft tissue as a barrier. A healthy junctional epithelium (JE) served as positive control. RESULTS: No differences were observed in the rate of soft-tissue integration of immediate versus delayed implants; however, overall, mucosal integration took at least twice as long as osseointegration in this model. Qualitative assessment of Vimentin expression over the time course of soft-tissue integration indicated an initially disorganized peri-implant connective tissue envelope that gradually matured with time. Quantitative analyses showed significantly less total collagen in peri-implant connective tissues compared to connective tissue around teeth around implants. Quantitative analyses also showed a gradual increase in expression of hemidesmosomal attachment proteins in the peri-implant epithelium (PIE), which was accompanied by a significant inflammatory marker reduction. CONCLUSIONS: Within the timeframe examined, quantitative analyses showed that connective tissue maturation never reached that observed around teeth. Hemidesmosomal attachment protein expression levels were also significantly reduced compared to those in an intact JE, although quantitative analyses indicated that macrophage density in the peri-implant environment was reduced over time, suggesting an improvement in PIE barrier functions. Perhaps most unexpectedly, maturation of the peri-implant soft tissues was a significantly slower process than osseointegration.

A 13- to 17-year Retrospective Evaluation of the Clinical Performances of Anterior and Posterior Lithium Disilicate Restorations onto Teeth and Implants.

This retrospective study aimed at evaluating the clinical outcomes of lithium disilicate prostheses onto teeth and implants. A total of 860 restorations were delivered to 312 patients, including crowns, veneers and onlays. Patients with uncontrolled gingival inflammation and/or periodontitis were excluded, whilst subjects with occlusal parafunctions were included. The retrospective observational period ranged between 13 to 17 years. The mechanical and esthetic performances of the restorations were rated according to the modified CDA criteria. The recorded data were analyzed statistically. In total, 26 mechanical complications were noticed: 17 ceramic chippings, 5 core fractures and 4 losses of retention. Mechanical complications occurred predominantly in posterior areas; monolithic prostheses showed the lowest percentage of structural problems. The clinical scores of layered and monolithic restorations were fully satisfactory according to the modified CDA rating. The cumulative survival and success rates ranged between 95.46-100% and 93.75-100% respectively up to 17 years of follow-up. Although patient selection and the rigorous application of validated clinical protocols were considered paramount, the use of lithium disilicate prostheses onto teeth and implants was reported to be a viable and reliable treatment option in the long-term.

Long-term survival and success of zirconia screw-retained implant-supported prostheses for up to 12 years: A retrospective multicenter study.

STATEMENT OF PROBLEM: Despite the broad clinical application of zirconia for fixed implant-supported prostheses, evidence of long-term performance is sparse. PURPOSE: The purpose of this retrospective study was to evaluate the long-term clinical and radiographic outcomes of zirconia-based partial and complete screw-retained implant-supported zirconia fixed dental prostheses (ISZFDPs). MATERIAL AND METHODS: Records of patients treated with dental implants and ISZFDPs between December 2004 and June 2017 were screened. Eligible study participants, according to inclusion criteria, were contacted and invited to undergo clinical and radiographic examinations. Outcomes were evaluated as implant and prosthetic survival rates, prosthetic success rate, complications, marginal bone level (MBL) change, and soft tissue condition. Along with the effects of zirconia prosthesis type and level, the effects of implant type and connection, type of loading, and follow-up on MBL were tested with a generalized linear effects model (GLEM) (α=.05). RESULTS: A total of 118 patients were identified, of whom 20 (16.9%) were not available for clinical examination for various reasons. Ninety-eight participants (mean age 60.7 ±11.7 years) with 337 implants were included, of which 176 (52.2%) had been immediately loaded. A total of 111 ISZFDPs (96 zirconia connection and 15 titanium base) were investigated: 24 complete ISZFDPs with a zirconia connection (12.9 ±0.97 dental units, minimum 12, maximum 14), 72 partial with a zirconia connection (3.11 ±1.12, minimum 2, maximum 7), 15 partial with a titanium base (3.62 ±1.02, minimum 2, maximum 5). Forty ISZFDPs had been in function for ≥10 years (36%), 38 for 5 to 9 years (34.2%), and 33 for 2 to 4 years (22.8%). The mean follow-up time was 7.2 ±3.4 years. No zirconia fractures were identified. Two implants and 2 ISZFDPs failed, with chipping being the most common complication (13.5%). The implant survival rate was 99.4%, and the prosthetic survival rate was 98.2%. The cumulative prosthetic success rate was 91.9%. MBL change was -0.18 ±0.59 mm. Thirteen implants were treated for peri-implantitis (3.8%), and 9 for mucositis (2.7%), but presented healthy peri-implant soft tissues at the follow-up examination. A significant difference was found between the implant-level and abutment-level prostheses (P=.013), with less marginal bone loss observed in ISZFDPs delivered at the implant level. CONCLUSIONS: Zirconia-based screw-retained implant-supported prosthesis can be considered a reliable long-term treatment option for partial and complete edentulism. No zirconia fractures were experienced. Stable bone levels and low peri-implantitis rates were reported regardless of the ISZFDP type and level, implant type and connection, and type of loading.

A Retrospective Observational Study Assessing the Clinical Outcomes of a Novel Implant System with Low-Speed Site Preparation Protocol and Tri-Oval Implant Geometry.

A novel, biologically friendly implant concept system introduces low-speed (50 rpm) site preparation instruments used without irrigation and a tri-oval, tapered implant designed to reduce stress on cortical bone without sacrificing mechanical stability. This retrospective, observational, multicenter study (clinicaltrials.gov NCT04736771) collected data from consecutive patients treated with at least one novel concept system implant to evaluate clinical outcomes after 1 year in function. The primary endpoint was a marginal bone level change (MBLC) from loading to 1 year, and secondary endpoints included implant survival and clinician feedback. Ninety-five patients (54 women and 41 men, mean age: 58 ± 12 years) were treated with 165 implants. For 94.5% of implants, site preparation was performed in two steps. The mean follow-up from implant insertion was 1.8 ± 0.2 years. Mean MBLC from implant loading to 1-year follow-up was +0.15 ± 0.85 mm (n = 124 implants). At the last follow-up, the implant survival rate was 98.0%. Clinician satisfaction with the novel concept system was high. The novel concept system offers an easy-to-use implant placement protocol, with most implants placed using two steps. The minimal bone remodeling and high survival rate observed across a variety of indications and treatment protocols demonstrate broad versatility and confirm the clinical benefits of this biologically friendly innovation.

A Biologically Driven Concept to Design the Emergence Profile Around Dental Implants: Surgical and Prosthetic Considerations to Optimize Hard and Soft Tissue Integration.

The emergence profile is a crucial factor in facilitating favorable esthetic outcomes and maintaining peri-implant health and stability. It should be evaluated not simply in terms of morphology but as a clinical variable closely related to material properties and clinical approaches; in this way, this critical factor-which can significantly influence the integration, stability, and preservation of bone and soft tissues-can be comprehensively planned. Soft tissue integration and adherence to prosthetic components are paramount elements in the preservation and protection of bone from contamination and infection. The present narrative paper presents a prosthetic concept suggested as an operative strategy to preserve peri-implant hard and soft tissues and achieve predictable prosthetic outcomes, optimizing soft tissue integration. Achieving an ideal soft tissue seal around implants is paramount in achieving stable restorations and protecting the bone interface from possible contamination and infection.

Clinical Performance of a Novel Two-Piece Abutment Concept: Results from a Prospective Study with a 1-Year Follow-Up.

Development of a stable and healthy soft-tissue barrier around dental implants is key to long-term success of implant-supported prostheses. The novel two-piece abutment concept shifts the prosthetic interface to the soft-tissue level to protect bone interface/connective tissue during the healing phase and restorative procedures. This prospective study included 72 patients treated with 106 implants to support a single-tooth or a three-unit bridge restored with two-piece abutments. The evaluation included marginal bone level change (MBLC), implant and prosthetic survival, soft-tissue health including keratinized mucosa height and mucosal margin position, patient quality of life (QoL) and satisfaction, and clinician satisfaction and ease-of-use rating of the concept. Mean MBLC from implant placement to 1 year was -0.36 ± 1.26 mm (n = 89), the 1-year implant and prosthetic survival rates were 97.1 and 96.7%, respectively, while keratinized mucosa height increased from 2.9 ± 1.2 mm at prosthetic delivery to 3.2 ± 1.3 mm, and mucosal margin migrated coronally by 0.49 ± 0.61 mm by 1 year. Patient satisfaction and QoL were high. Clinicians were satisfied with the esthetic and functional results and rated the concept as easy to use. In conclusion, the novel two-piece abutment concept promotes good peri-implant tissue health, while providing an easy-to-use workflow and high treatment satisfaction to both patients and clinicians.

The full-mouth mock-up: a dynamic diagnostic approach (DDA) to test function and esthetics in complex rehabilitations with increased vertical dimension of occlusion.

The mock-up is a diagnostic technique that allows for the intraoral try-in of a prosthetic rehabilitation. Mock-ups facilitate significant improvement in communication with patients by showing them the potential final outcome of the treatment. They also allow for a quick and easy comparison of the pre- and postoperative situations, and permit the clinician to check the functional aspects of the therapy. The purpose of this article is to describe the use of the full-mouth mock-up technique for testing all the functional and esthetic parameters of extensive rehabilitations associated with a VDO increase with completely additive wax-ups. The proposed clinical procedures describe an easy and reversible technique to manage complex prosthetic cases with a more conservative and operator-friendly approach compared with conventional prosthetic therapies, reducing time and costs. All the clinical and technical phases of this approach are described step by step.

Increasing the Vertical Dimension of Occlusion: A Multicenter Retrospective Clinical Comparative Study on 100 Patients with Fixed Tooth-Supported, Mixed, and Implant-Supported Full-Arch Rehabilitations.

This multicenter retrospective clinical study was aimed at comparing the effects of an increase in vertical dimension of occlusion (VDO) in patients with fixed rehabilitations. Expert clinicians retrospectively evaluated 100 patients treated with an increase of the VDO and fixed dental prostheses (FDPs) supported by teeth, implants, or both. The patients were divided into three study groups according to the type of support of restorations in posterior areas, as follows: partially edentulous patients with posterior teeth-supported rehabilitations and no implants in posterior segments (group A), partially edentulous patients with posterior mixed rehabilitations and at least one osseointegrated implant in posterior segments (group B), and completely edentulous patients with posterior implant-supported rehabilitations (group C). The new VDO was tested with mock-ups, temporary restorations, or removable appliances. The patients were followed up for at least 1 year after the delivery of final restorations. Clinical variables were collected retrospectively, such as presence of referred self-reported bruxism and temporomandibular joint or muscle symptoms before treatment, extension of the dental arches, increase in VDO, restorative materials, and functional complications. Descriptive statistics were analyzed; the three experimental groups were compared with one-way analysis of variance (ANOVA) followed by Tukey post hoc test for the quantitative variables and with logistic regression using the likelihood ratio test for the qualitative variables. Statistically significant differences were reported among the experimental groups for functional complications. Functional and prosthetic complications after the VDO increase were not frequent. Functional complications were mainly noticed in group C but usually were no longer evident after 2 weeks. No significant differences were found between groups in terms of prosthetic complications and self-reported bruxism.

Clinical Evaluation of the Influence of Connection Type and Restoration Height on the Reliability of Zirconia Abutments: A Retrospective Study on 965 Abutments with a Mean 6-Year Follow-Up.

This multicenter retrospective clinical study aimed to evaluate the clinical performance of zirconia abutments in anterior and posterior regions, focusing on implant-abutment connections and restoration vertical height (RVH). Six experienced prosthodontists used 965 computer-aided design/computer-assisted manufacture zirconia abutments in 601 patients. Different surgical approaches were taken according to the needs of each patient. The final restorations were all-ceramic single crowns and short-span fixed dental prostheses. Screw-retained restorations were mainly used in anterior areas, whereas cemented prostheses were chosen in cases where the implant position was not ideal. Different types of implant-abutment connections were compared: external, internal with metal components, and internal full-zirconia conical connection. All the restorations were followed up for 4 to 10 years. Technical and biologic complications were assessed in relation to several biomechanical variables, such as RVH. Differences between groups were statistically analyzed, and longevity of abutments was evaluated according to Kaplan-Meier survival analysis. Zirconia abutments resulted in overall survival and success rates of 98.9% and 94.8%, respectively. External connections reported survival and success rates of 99.7% and 94.5%, internal metal connections 99.8% and 95.5%, and internal zirconia connections 93.1% and 93.1%, respectively. Overall complication rates of 1.14%, 3.42%, and 0.62% were reported for fractures, chipping, and unscrewing, respectively. The external connection showed the longest survival while the internal zirconia connection showed the highest fracture incidence over the observation period. The clinical risk limit of RVH was identified as 14 mm. Zirconia abutments showed satisfactory clinical performance in anterior and posterior regions after 4 to 10 years. RVH and connection type influenced the clinical longevity of restorations; in particular, internal connections with secondary metallic components reduced the incidence of complications.

Clinical reliability of CAD/CAM cross-arch zirconia bridges on immediately loaded implants placed with computer-assisted/template-guided surgery: a retrospective study with a follow-up between 3 and 5 years.

PURPOSE: The purpose of this study is to retrospectively evaluate the implant and prosthetic survival and success rates of zirconia-based, implant-supported, screw-retained, cross-arch restorations up to 5 years after placement. MATERIALS AND METHODS: Twenty-two consecutive edentulous patients (11 males and females, each; mean age 68.3 years) received 26 CAD/CAM cross-arch zirconia implant bridges (NobelProcera™ Implant Bridge Zirconia; Nobel Biocare AG, Zurich, Switzerland) supported by 4 to 10 implants each. All patients were followed for at least 3 years (range 36-60 months, mean 42.3 months). Clinical assessments were scheduled every 4 months during hygiene maintenance. Outcomes were implant and prosthetic survival rates, prosthetic success rate, any observed clinical complications, patient satisfaction, and soft tissue parameters. Fisher's exact test was used to assess associations between categorical variables. RESULTS: No dropouts occurred. The overall implant and prostheses survival rate up to 5 years was 100%. Three out of 26 restorations (five out of three hundred forty eight dental units) showed an adhesive chip-off fracture of the veneering ceramic, scoring a cumulative prosthetic success rate of 88.5% at the prosthetic level and 98.6% at the unit level. All 22 patients were functionally and aesthetically highly satisfied with their restorations. Successful soft tissue parameters were found around all implants. CONCLUSIONS: Industrially manufactured, zirconia-based, implant-supported, screw-retained, cross-arch restorations are a viable alternative to conventionally manufactured porcelain-fused-to-metal restorations for rehabilitating the edentulous patient.

A novel approach to implant screw-retained restorations: adhesive combination between zirconia frameworks and monolithic lithium disilicate.

The use of zirconia is an esthetic alternative to metal for implant-supported frameworks, and it has increased primarily for its high biocompatibility, low bacterial surface adhesion, high flexural strength and high mechanical features. The zirconia frameworks in fixed prosthetic restorations that are supported by implants is commonly covered with hand-layered overlay porcelain. This technical procedure is highly esthetic but it can cause some complications, such as porcelain fractures. The purpose of this article is to introduce an innovative approach to create an esthetic fixed ceramic implant restoration to minimize and facilitate the repair of the mechanical complications, by combining the adhesive-cementation of lithium disilicate full coverage restorations on implant screw-retained zirconia frameworks.

Clinical evaluation of 860 anterior and posterior lithium disilicate restorations: retrospective study with a mean follow-up of 3 years and a maximum observational period of 6 years.

This study aimed to assess the clinical performance of lithium disilicate restorations supported by natural teeth or implants. Eight hundred sixty lithium disilicate adhesive restorations, including crowns on natural teeth and implant abutments, veneers, and onlays, were made in 312 patients. Parafunctional patients were included, but subjects with uncontrolled periodontitis and gingival inflammation were excluded. Veneers up to 0.5 mm thick were luted with flowable composite resin or light curing cements, while dual-curing composite systems were used with veneers up to 0.8 mm thick. Onlays up to 2 mm in thickness were luted with flowable composite resins or dual-curing composite cements. Crowns up to 1 mm in thickness were cemented with self-adhesive or dual-curing resin cements. The observational period ranged from 12 to 72 months, with a mean follow-up of 3 years. The mechanical and esthetic outcomes of the restorations were evaluated according to the modified California Dental Association (CDA) criteria. Data were analyzed with descriptive statistics. Twenty-six mechanical complications were observed: 17 porcelain chippings, 5 fractures, and 4 losses of retention. Structural drawbacks occurred mainly in posterior segments, and monolithic restorations showed the lowest number of mechanical complications. The clinical ratings of the successful restorations, both monolithic and layered, were satisfactory according to the modified CDA criteria for color match, porcelain surface, and marginal integrity. The cumulative survival rates of lithium disilicate restorations ranged from 95.46% to 100%, while cumulative success rates ranged from 95.39% to 100%. All restorations recorded very high survival and success rates. The use of lithium disilicate restorations in fixed prosthodontics proved to be effective and reliable in the short- and medium-term.

Anterior discolored teeth restored with procera all-ceramic restorations: a clinical evaluation of the esthetic outcome based on the thickness of the core selected.

UNLABELLED: The most common esthetic challenge associated with endodontics is the discoloration of natural tooth structure. Also in fixed prosthesis, discolorations represent an esthetic limit, particularly in the case of all-ceramic restorations. In fact, the final esthetic result can be compromised by the grey radiated through the coping and soft tissue. PURPOSE: The aim of the study was to evaluate the masking ability of Procera alumina restorations. MATERIALS AND METHODS: Clinical evaluation was investigated by using tests of discolored teeth. Each abutment, classified with Natural Die Material (Ivoclar Vivadent), were manufactured three alumina copings with thickness of 0.4, 0.6, and 0.8 mm, respectively. Masking ability for each coping was evaluated in relation to the degree of discoloration. On the basis of the results obtained, seventeen discolored teeth, treated with Procera alumina restorations, were evaluated. Color match, porcelain surface, marginal discoloration, and marginal integrity were clinically examined following modified CDA/Ryge criteria. CONCLUSION: The Procera AllCeram alumina system seems to be a reliable and excellent technology for the prosthetic treatment of moderate and serious discolored anterior teeth with an exceptionally natural look.

Guided bone regeneration technique in the esthetic zone: a novel approach using resorbable PLLA-PGA plates and screw fixation. A case report.

The use of biodegradable fixation materials or devices during maxillofacial, craniofacial, and orthopedic reconstructive surgical procedures reduces or eliminates the need to perform a second surgical procedure, which would otherwise be required to remove a nonbiodegradable device. This article presents a novel approach to augment a horizontally deficient alveolar ridge using both a resorbable plate/screw fixation system composed of a polylactic acid-polyglycolic acid (PLLA-PGA) copolymer to provide a rigid scaffolding for the bone chips and a resorbable collagen barrier (Bio-Gide, Osteohealth) to secure the graft material. For periodontal reconstructive procedures, such as guided bone regeneration, the clinical application of this technique may be advantageous and also provide a more esthetic result by minimizing the need for an additional surgical procedure. (Int J Periodontics Restorative Dent 2009;29:543-547.).

Recreating an aesthetic smile: multidisciplinary and metal-free approach using CAD/CAM technology.

The aesthetic rehabilitation of patients with functionally compromised dentition frequently involves a multidisciplinary approach. A correct aesthetic diagnosis, treatment plan, and careful material selection are critical factors in successful restoration. A team approach that includes the clinicians, the laboratory technician, and the patient is essential to achieve the desired result. The following case presentation demonstrates a successful multidisciplinary approach used to recreate an aesthetic smile in a young patient with functionally and aesthetically compromised anterior maxillary dentition.

Immediate loading and flapless, postextraction, single-tooth implant restoration: advantages and indications.

Tooth extraction inevitably implies significant alterations to the hard and soft tissues with a loss of the preexisting tissue morphology. The re-establishment of the normal tissue architecture is the greatest challenge that the dental professional must overcome in order to obtain pleasing aesthetic results. The following case presentations depict single-tooth immediate implant restoration in aesthetic regions using a flapless approach with immediate loading. This technique is relatively simple, can be used in a variety of clinical situations, and can provide excellent results.