Implant-supported single all-ceramic crowns made from prefabricated (stock) or individualized CAD/CAM zirconia abutments: A 5 year randomized clinical trial.

AIM: The aim of this randomized, prospective, and clinical multicenter study was to compare the overall clinical performance of two restorative options over a 5-year period: individualized CAD/CAM abutments veneered with a hand-layered ceramic, and prefabricated zirconium dioxide abutments veneered with press ceramic and inserted into a single edentulous gap in the anterior maxilla. MATERIALS AND METHODS: Forty subjects were recruited from two universities: 20 from the University of XX and 20 from the University of XY. Each subject received an implant to restore a single edentulous gap in the maxillary anterior region (14-24 FDI). 20 patients were randomized into each Group. Group A received a one-piece single crown produced from a prefabricated zirconia abutment with pressed ceramic and Group B received an individualized CAD/CAM zirconia abutment with a hand-layered technique. After 5 years, the aesthetic and radiographic parameters were assessed. RESULTS: Group A had four dropouts and one failure, resulting in a 95% survival rate and 95% success rate. Group B had two dropouts and two failures which resulted in a 90% survival rate and 90% success rate. No crestal bone level changes were observed, with a mean DIB of 0.06 mm in Group A and 0.09 mm in Group B. No statistically significant differences were present at baseline, 6 months, 1 year, 3 years, or 5 years for DIB values between time points and groups. Pink aesthetic score/white aesthetic score, Peri-Implant and Crown Index, and Implant Crown Aesthetic Index values were stable over time at all five points for both groups. CONCLUSION: Both implant-supported restorative options represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla. CLINICAL SIGNIFICANCE: In general, the use of ceramic abutments in the anterior zone represents a valuable treatment procedure with both standardized and CAD/CAM individualized abutments and following the recommendations from the respective manufacturer(s).

Selection criteria for immediate implant placement and immediate loading for single tooth replacement in the maxillary esthetic zone: A systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to review available evidence for Type 1A (immediate implant placement and immediate loading) of single tooth replacement in the maxillary esthetic zone. MATERIALS AND METHODS: An electronic search was conducted utilizing the databases of MEDLINE, Embase, and Cochrane to identify publications reporting on the outcomes of Type 1A for single tooth replacement in the maxillary esthetic zone. The success and survival rates of the included articles were reported, which were further categorized according to the clinical criteria reported in Type 1A. Mean survival rates were univariately compared between risk groups and additionally between studies published before and since 2012 using bias-corrected and study size-weighed bootstrap tests. A study time-correcting meta-analysis was then performed to obtain an overall effect for the study pool. RESULTS: A total of 3118 publications were identified in the search, with a total of 68 articles included. A mean number of implants per study were 37.2 and mean follow-up was 2.8 years. All the included studies utilizing Type 1A report highly selective inclusion and exclusion criteria. Univariate risk group comparison determined that studies before 2012 report a significantly lower mean survival rate (difference of -1.9 percentage points [PP], 95% CI: [-0.3, -4.0], p = .02), facial gap dimension had an impact on survival rates (+3.1 PP [0.2, 5.3] for width >2 mm, p = .04), as well as presence of endodontic infection (+2.6 PP [0.9, 5.1], p = .004). CONCLUSIONS: Type 1A has a high survival rate in studies reporting strict patient and site selection criteria. Further research is required to assess esthetic and functional success with Type 1A treatments.

Clinical performance of immediately placed and immediately loaded single implants in the esthetic zone: A systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to assess the following PIO question: In adult patients treated with an indication for single tooth extraction in the maxillary esthetic zone (15-25), what is the influence of an immediate implant placement and immediate loading protocol on the clinical performance (primary aim) and esthetic outcomes (secondary aim) focusing on investigations published after 2010. MATERIAL AND METHODS: An electronic search in Medline (PubMed), the Cochrane Central Register of Controlled Trials, and EMBASE databases up to April 2022 was performed to identify clinical studies investigating the outcome of single implants subjected to immediate placement with immediate restoration/loading (Type 1A). RESULTS: Sixty-three studies (10 randomized controlled trials, 28 prospective and 25 retrospective cohort studies) were included with a follow-up ranging from 12 to 96 months. One thousand nine hundred sixty-one implants reported survival rates of 99.2 (98.6-99.5) % at 1 year, 97.5 (95.9-98.4) % after 3 years, and 95.8 (93.3-97.4) % after 5 years; 1064 immediately loaded restorations presented survival rates of 98.9 (97.8-99.5) % after 1 year, 96.8 (93.6-98.4) % after 2 years, and 94.8 (89.6-97.4) % after 5 years. Comparing baseline to 12-month data using the Hedges' g effect size (95% CI), papilla height presented an overall effect size of -0.71 (-1.25, -0.1) mm, midfacial recession change of -0.15 (-0.66, 0.36) mm, and a 0.82 (0.37, 1.28) gain in PES. CONCLUSIONS: Immediate implant placement and immediate loading can be considered a predictable and safe treatment option for single maxillary anterior restorations with adequate survival rates and favorable esthetics outcomes for up to 5 years.

Distortion assessment of different materials in full-arch dentate impressions in relation to operator experience: a comparative in vivo.

PURPOSE: Evaluating the distortion probability in impressions of completely dentate arches when different impression materials are used in relation to operator experience. MATERIAL AND METHODS: Twenty-eight students (group A) and 7 dentists (group B) performed 3 maxillary impressions on 28 students (participants), each using vinyl siloxane ether (VSE), polyether (PE), and irreversible hydrocolloid (IHC). Gypsum master casts were fabricated and subsequently digitized. Intraoral scans were taken as a control. Differences between master casts and intraoral scans were visualized by heatmaps and planar deviations were investigated. If planar deviations of >120 µm were found, the impression was rated as "distorted." An additional superimposition using the casts from VSE or PE was performed to confirm the presence of distortions. The relative number of surfaces with distortions in each impression was calculated. The procedure was repeated for a distortion threshold of 500 µm. The statistical analyses included measures ANOVA and post-hoc tests (a < 0.05). RESULTS: When 120 µm was considered as the threshold for distortions, IHC impressions showed higher distortion probability than PE impressions in group A (P = 0.003) and group B (P < 0.0001). In group B only, PE showed a lower distortion probability than VSE (P = 0.02). There was no difference between the study groups (P = 0.42). Considering 500 µm as a threshold for distortions, there was no difference between impression materials (P = 0.17) or study groups (P = 0.53). CONCLUSION: There were no statistic significant differences in relation to operator experience. Different impression materials had a significant impact on distortion probability. Polyether impressions showed the lowest distortion probability. Int J Prosthodont. 10.11607/ijp.8555.

Patient-reported outcome measures focusing on the esthetics of implant-compared to tooth-supported single crowns-A systematic review and meta-analysis.

OBJECTIVES: To report a summary of published patient-reported esthetic outcome measures (PROMs) of implant-supported single crowns (SCs) compared with those of tooth-supported SCs. MATERIALS AND METHODS: Cochrane, Medline (PubMed), and EMBASE database search was performed by three reviewers on reports with patient-reported esthetic outcomes of tooth- and implant-supported SCs. Clinical studies with at least 12 months of mean follow-up period and a minimum of 10 patients, and English, French, or German reports were included. To compare the subgroups, for aggregate-level data, random-effects meta-regression was used. RESULTS: Two thousand fifteen titles were identified (initial search) and screened independently concluding 53 full-text articles to include in data extraction. Twenty-two studies with 29 study cohorts were included. Patients were satisfied with the esthetics of implant- and tooth- supported crowns Mean visual analogue scale (VAS) value from the PROMs data of 1270 implant-supported SCs evaluated by 1051 patients was 89.6% (80.0%-94.1%). The mean VAS value of patients (n = 201), who evaluated the esthetic outcome of 486 tooth-supported SCs was 94.4% (92.3%-96.0%). VAS scores of patients regarding their perception of esthetics did not show any difference among different crown materials or type of implant used. The patients' perception of esthetics focusing on SC had a tendency to be higher when the crowns were supported by teeth, however, no statistical difference was found when compared with implant-supported crowns (p = 0.067). CONCLUSIONS: Patient perception of esthetics in SCs was not affected by the type of support, crown material, implant, and presence of provisional crown for both implant- and tooth-supported SCs. CLINICAL SIGNIFICANCE: Despite that patient's expectations are increasing overall Patients are satisfied with with esthetic outcome of implant- and tooth-supported crowns.

The influence of age and gender on perception of orofacial esthetics among laypersons in Switzerland.

OBJECTIVE: The purpose of this study was to evaluate the perception and role of orofacial esthetics by laypersons, and how attitudes may be correlated with age and gender in Switzerland. MATERIAL AND METHODS: Self-administrated questionnaires (SAQ) were distributed both conventionally and digitally to Swiss residents over 16 years of age (range 16-99 years). The participants were identified in the medical practice, at an open house of the ZMK Bern, in elderly care centers, and via the internet (Facebook and Instagram). To verify that the participants were Swiss residents and laypersons, they were checked by an operator (conventional) or were provided an exact description of eligible participants at the beginning of the SAQ (digital). The SAQ included 30 questions with multiple-choice responses and visual analogue scales (0-100) divided into four sections regarding dental appearance with respect to body esthetics, partner selection, employment and career opportunities, and overall health/quality-of-life. For statistical analysis, respondents were segregated into two age groups (<25 years and ≥25 years) and into two gender groups (male and female). Descriptive analyses, the Fisher exact test, and Welch's t-test were applied (α = 0.05). RESULTS: Five hundred and two laypersons completed the SAQ. The study's hypothesis-that various age groups and genders have different perceptions of dental esthetics-was supported. The willingness to correct one's own dentition was lower among older participants (OR: 0.54; p = 0.001); charisma and dental esthetics were considered equally important with a trend toward charisma in both age groups (p = 0.003). The belief that excellent dentition improves employment chances at a job interview (OR: 0.47; p = 0.0003) was significantly lower among older participants, and the belief that dental correction would improve quality-of-life was significantly higher among older participants (OR: 1.81; p = 0.001). The assumption that individuals with attractive teeth appear happier was significantly lower among older respondents (OR: 0.67; p = 0.03). Women were less satisfied with their dental appearance and, proportionally, their willingness to receive correction was significantly higher (OR: 1.79; p = 0.01 and OR: 1.77; p = 0.002 relative to men, respectively). Moreover, male participants had a lower desire to have brighter teeth and undergo bleaching treatments (OR: 0.54; p = 0.002; OR: 0.53; p = 0.002). The proportion of men believing that having beautiful teeth improves attractiveness and employment chances was significantly lower (OR: 0.33; p = 0.02 and OR: 0.66; p = 0.04; respectively). CONCLUSIONS: Within the limitations of this observational study, it was concluded that age and gender of laypersons in Switzerland have a significant impact on the perception of dental esthetics. CLINICAL SIGNIFICANCE: Evaluating and quantifying perceptions of dental esthetics for daily life across various age groups and genders can improve clinicians' understanding of individual needs in order to offer patient-oriented dental care.

Short strategic implants for mandibular removable partial dentures: One-year results from a pilot randomized crossover abutment type study.

OBJECTIVES: The present pilot study analyzed two abutment types (a retentive ball and a non-retentive dome) in implant-assisted removable partial dentures (IARPDs) on 6 mm short implants with respect to clinical, radiological, and patient-reported outcomes (PROs), during the first year. MATERIALS AND METHODS: Two implants were placed bilaterally in mandibular molar sites, converting existing free-end removable partial dentures (RPDs) to IARPDs. Twelve subjects were randomized to initially receive either the dome (Group A, n = 6) or the ball abutment (Group B, n = 6). After eight weeks, the abutments were exchanged. After another 8 weeks, the participants were given the choice of one of the abutments. Mean values and standard deviations (SD) were calculated, and random-effect linear regression analyses were applied to analyze marginal bone level alterations and PROs (α < .05). RESULTS: Twelve participants were included in the study; however, one dropout occurred. Patient ratings increased significantly in both study groups. The majority of the participants (82%) ultimately chose the ball abutment. The implant survival rate was 100%, and the success rate was 90.9% twelve months after implant placement (mean peri-implant bone-loss: -1.2; SD: 0.6 mm) without a statistically significant difference between the study groups, in terms of clinical- and radiological outcomes. CONCLUSION: Placing 6 mm short implants at mandibular molar sites of RPD wearers seems to be a viable treatment option, based on this investigation with a short-term follow-up. Although only minor differences between the two abutments were observed, patients seem to prefer the ball over the dome abutment.

Accuracy of intraoral scanning in completely and partially edentulous maxillary and mandibular jaws: an in vitro analysis.

OBJECTIVES: New generation intraoral scanners are promoted to be suitable for digital scans of long-span edentulous spaces and completely edentulous arches; however, the evidence is lacking. The current study evaluated the accuracy of intraoral scanning (IOS) in partially and completely edentulous arch models and analyzed the influence of operator experience on accuracy. MATERIALS AND METHODS: Four different resin models (completely and partially edentulous maxilla and mandible) were scanned, using a new generation IOS device (n = 20 each). Ten scans of each model were performed by an IOS-experienced and an inexperienced operator. An industrial high-precision scanner was employed to obtain reference scans. IOS files of each model-operator combination, their respective reference scan files (n = 10 each; total = 80), as well as the IOS files from each model generated by the same operator, were superimposed (n = 45; total = 360) to calculate trueness and precision. An ANOVA for mixed models and post hoc t tests for mixed models were used to assess group-wise differences (α = 0.05). RESULTS: The median overall trueness and precision were 24.2 µm (IQR 20.7-27.4 µm) and 18.3 µm (IQR 14.4-22.1 µm), respectively. The scans of the inexperienced operator had significantly higher trueness in the edentulous mandibular model (p = 0.0001) and higher precision in the edentulous maxillary model (p = 0.0004). CONCLUSION: The accuracy of IOS for partially and completely edentulous arches in in vitro settings was high. Experience with IOS had small influence on the accuracy of the scans. CLINICAL RELEVANCE: IOS with the tested new generation intraoral scanner may be suitable for the fabrication of removable dentures regardless of clinician's experience in IOS.

Clinical and esthetic outcomes of two different prosthetic workflows for implant-supported all-ceramic single crowns-3 year results of a randomized multicenter clinical trail.

OBJECTIVE: The aim of this randomized multicenter clinical trial was to evaluate and compare the performance of anterior all-ceramic implant crowns based either on prefabricated zirconia abutments veneered with pressed ceramics or on CAD/CAM zirconia abutments veneered with the hand build-up technique. The null hypothesis was that there is no statistically significant difference between the two study groups. MATERIAL AND METHODS: Forty implants were inserted in sites 14-24 (World Dental Federation [FDI]) in two centers, the Universities of Bern and Geneva, Switzerland. Twenty patients each were randomized into either Group A and restored with one-piece single crown made of a prefabricated zirconia abutment with pressed ceramic, or Group B using an individualized CAD/CAM zirconia abutment with the hand-layered technique. After 3 years, clinical, esthetic, and radiographic parameters were assessed. RESULTS: Group A exhibited one dropout patient and one failure resulting in a survival rate of 89% after 3 years and two failures for Group B (90%). Clinical parameters presented healthy peri-implant soft tissues. Overall, no crestal bone level changes were observed (mean DIB of 0.13 mm [Group A] and 0.24 mm [Group B]). There were no significant differences at baseline, 6 months, and 1 and 3 years for DIB values between the two groups. PES and WES values evaluated at all three time points indicated stability over time for both groups and pleasing esthetic outcomes. CONCLUSIONS: Both implant-supported prosthetic pathways represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla.

Influence of implant macrodesign and insertion connection technology on the accuracy of static computer-assisted implant surgery.

OBJECTIVE: The aim of this study was to evaluate the effect of three different macrodesigns and two different insertion devices on the accuracy of static computer-assisted implant surgery (sCAIS). MATERIALS AND METHODS: Ninety implant replicas with three different macrodesigns: Soft tissue level (TL), bone level (BL), and bone level tapered (BLT) were placed in 30 dental models with two implant insertion devices: Guided adapter and guided screwed-in mount. Preoperative and postoperative positions of implants were compared and the mean angular deviation, crestal, and apical three-dimensional (3D) deviation were calculated for each implant macrodesign and each insertion device. Data were analyzed using analysis of variance, post hoc t-tests and Bonferroni-Holm's adjustment method. P values less than .05 were considered statistically significant. RESULTS: BLT implants had lower mean 3D deviation values at the crest and the apex when compared with 3D deviations with BL and TL implants (P < .05). Also, BLT implants had lower angular deviations, when compared with BL and TL Implants, however, angular deviations were not statistically significant (P > .05). Considering the insertion device method, no significant differences were noted between insertion devices irrespective of the deviation analyzed. CONCLUSION: The macrodesign of dental implants may have an influence on the accuracy of sCAIS, with tapered designs offering slightly better positional accuracy than parallel-walled macrodesigns independent on the method of insertion used.

Influence of the fixed implant-supported provisional phase on the esthetic final outcome of implant-supported crowns: 3-year results of a randomized controlled clinical trial.

OBJECTIVES: The aim of this investigation was to evaluate whether the use of a provisional implant-supported crown improves the final esthetic outcome of implant crowns that are placed within esthetic sites. MATERIALS AND METHODS: Twenty endosseous implants were inserted in sites 13 to 23 (FDI) in 20 patients. Following the reopening procedure, a randomization process assigned them to either cohort group 1: a provisional phase with soft tissue conditioning using the "dynamic compression technique" or cohort group 2: without a provisional phase. Screw-retained all ceramic crowns were inserted. Clinical follow-up appointments were completed at 36 months evaluating clinical, radiographic outcomes, and implant success and survival. RESULTS: After 3 years, all implants survived; one implant-supported crown was excluded from the study due to adjacent tooth failure replaced with a further implant supported crown. Modified pink esthetic score (ModPES) scores were significantly different between groups 1 and 2 (P = .018); white esthetic scores (WES) were not statistically different between both groups (P = .194). Mean values of combined modPES and WES were 15.6 for group 1, with a SD of 3.20. Group 2 had a mean combined modPES and WES of 12.2, with a SD of 3.86. Mean bone loss after 3 year was -0.05 and -0.04 mm for groups 1 and 2 respectively, without being statistically significant. CONCLUSION: Fixed implant-supported provisionals improve the final esthetic outcome of the peri-implant mucosa.

Patient-reported outcome measures focusing on aesthetics of implant- and tooth-supported fixed dental prostheses: A systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review and meta-analysis was to summarize the existing evidence on patient-reported aesthetic outcome measures (PROMs) of implant-supported, relative to tooth-supported fixed dental prostheses. MATERIAL AND METHODS: In April 2017, two reviewers independently searched the Medline (PubMed), EMBASE, and Cochrane electronic databases, focusing on studies including patient-reported aesthetic outcomes of implant- and tooth-supported fixed dental prostheses (FDPs). Human studies with a mean follow-up period of at least 1 year, a minimum of ten patients, and English, German, or French publication were included. For the comparison of subgroups, random-effects meta-regression for aggregate-level data was used. RESULTS: The systematic search for implant-supported prostheses focusing on patient-reported outcomes identified 2,675 titles, which were screened by two independent authors. Fifty full-text articles were analyzed, and finally, 16 publications (including 19 relevant study cohorts) were included. For tooth-supported prostheses, no studies could be included. A total of 816 implant-supported reconstructions were analyzed by patients. Overall aesthetic evaluation by the patients' visual analogue scale (VAS) rating was high in implant-supported FDPs (median: 90.3; min-max: 80.0-94.0) and the surrounding mucosa (median: 84.7; min-max: 73.0-92.0). Individual restorative materials, implant neck design (i.e., tissue or bone level type implants), and the use of a fixed provisional had no effect on patients' ratings of the definitive implant-supported FDPs. CONCLUSIONS: Aesthetics is an important patient-reported measure, which lacks in standardized methods; however, patients' satisfaction was high for implant- supported FDPs and the surrounding mucosa.

Group 3 ITI Consensus Report: Patient-reported outcome measures associated with implant dentistry.

OBJECTIVES: The aim of Working Group 3 was to focus on three topics that were assessed using patient-reported outcome measures (PROMs). These topics included the following: (a) the aesthetics of tooth and implant-supported fixed dental prostheses focusing on partially edentulous patients, (b) a comparison of fixed and removable implant-retained prostheses for edentulous populations, and (c) immediate versus early/conventional loading of immediately placed implants in partially edentate patients. PROMs include ratings of satisfaction and oral health-related quality of life (QHRQoL), as well as other indicators, that is, pain, general health-related quality of life (e.g., SF-36). MATERIALS AND METHODS: The Consensus Conference Group 3 participants discussed the findings of the three systematic review manuscripts. Following comprehensive discussions, participants developed consensus statements and recommendations that were then discussed in larger plenary sessions. Following this, any necessary modifications were made and approved. RESULTS: Patients were very satisfied with the aesthetics of implant-supported fixed dental prostheses and the surrounding mucosa. Implant neck design, restorative material, or use of a provisional restoration did not influence patients' ratings. Edentulous patients highly rate both removable and fixed implant-supported prostheses. However, they rate their ability to maintain their oral hygiene significantly higher with the removable prosthesis. Both immediate provisionalization and conventional loading receive positive patient-reported outcomes. CONCLUSIONS: Patient-reported outcome measures should be gathered in every clinical study in which the outcomes of oral rehabilitation with dental implants are investigated. PROMs, such as patients' satisfaction and QHRQoL, should supplement other clinical parameters in our clinical definition of success.

Static computer-aided implant surgery (s-CAIS) analysing patient-reported outcome measures (PROMs), economics and surgical complications: A systematic review.

OBJECTIVE: To systematically evaluate the scientific literature for patient-reported outcome measures (PROMs) in static computer-aided implant surgery (s-CAIS). METHODS: A PICO strategy was executed using an electronic (MEDLINE, EMBASE, CENTRAL), plus manual search up to 15-06-2017 focusing on clinical studies investigating s-CAIS with regard to patients' pain & discomfort, economics and/or intra-operative complications. Search strategy was assembled from multiple conjunctions of MeSH Terms and unspecific free-text words. Assessment of risk of bias in selected studies was made at a "trial level" applying the Cochrane Collaboration Tool and the Newcastle-Ottawa Assessment Scale, respectively. RESULTS: The systematic search identified 112 titles. Seventy abstracts were screened, and 14 full texts were included for analysis. A total of 484 patients were treated with s-CAIS for placement of 2,510 implants. Due to the heterogeneity of the included studies, meta-analyses could not be performed. CONCLUSIONS: The number of identified studies investigating s-CAIS for PROMs was low. Scientifically proven recommendations for clinical routine cannot be given at this time; however, the number of clinical complications with s-CAIS seems to be negligible and comparable to conventional implant surgery. s-CAIS may offer a beneficial treatment option in edentulous cases if a flapless approach is applicable. Nevertheless, the economic effects in terms of time efficiency and treatment costs are unclear. Clinical investigations with well-designed RCTs investigating PROMs with standardized parameters are compellingly necessary for the field of s-CAIS.

Digital technology in fixed implant prosthodontics.

Digital protocols are increasingly influencing prosthodontic treatment concepts. Implant-supported single-unit and short-span reconstructions will benefit mostly from the present digital trends. In these protocols, monolithic implant crowns connected to prefabricated titanium abutments, which are created based on data obtained from an intraoral scan followed by virtual design and production, without the need of a physical master cast, have to be considered in lieu of conventional manufacturing techniques for posterior implant restorations. No space for storage is needed in the complete digital workflow, and if a remake is required a replica of the original reconstruction can be produced quickly and inexpensively using rapid prototyping. The technological process is split into subtractive methods, such as milling or laser ablation, and additive processing, such as three-dimensional printing and selective laser melting. The dimensions of the supra-implant soft-tissue architecture can be calculated in advance of implant placement, according to the morphologic copy, and consequently are individualized for each patient. All these technologies have to be considered before implementing new digital dental workflows in daily routine. The correct indication and application are prerequisite and crucial for the success of the overall therapy, and, finally, for a satisfied patient. This includes a teamwork approach and equally affects the clinician, the dental assistant and the technician as well. The digitization process has the potential to change the entire dental profession. The major benefits will be reduced production costs, improvement in time efficiency and fulfilment of patients' perceptions of a modernized treatment concept.

Screw retained vs. cement retained implant-supported fixed dental prosthesis.

A fixed dental prosthesis can be secured to an endosseous implant via cementation (using a provisional or definitive cement) on an implant abutment that is screw retained to the implant or directly in the implant via screw retention. The clinical decision as to which retention system best suits the individual patient depends on several factors. The aim of this review is to present a detailed overview of the factors potentially influencing whether to choose screw retention or cement retention. These factors include the individual indication, advantages and disadvantages of the different retention mechanisms, the retention provided, retrievability, provisionalization, esthetics and clinical performance, including failures and complications. The results of recently published systematic reviews on this topic are discussed and an overview is provided. A decision tree is presented to facilitate the clinical selection of the retention type. This overview concludes that the choice of retention type (screw retained or cement retained) might not influence the overall survival of the implant-supported fixed dental prosthesis, but may be responsible for the development of certain complications. The decision may depend on technical feasibility and on weighing the pros and cons.

Volumetric Calculation of Supraimplant Submergence Profile After Soft Tissue Conditioning with a Provisional Restoration.

The objective of this study was to digitally analyze the emergence profile changes before and after soft tissue conditioning with fixed-implant provisional restorations. Impressions were taken with individualized posts to build casts for 20 patients. Optical scanning of the modulated mucosa was performed from the model situations in combination with the original healing abutments. Emergence profile extension revealed a mean volume of 41.9 mm3 for central sites and 25.8 mm3 for laterals. In addition, linear calculations of supraimplant mucosal profile changes presented a median enlargement of 8.2 mm in the mesial-distal and 7.2 mm in the buccal-lingual direction for central incisors and 6.8 mm (mesial-distal) and 6.5 mm (buccal-lingual) for lateral incisors. The change was more than double compared with the initial profile of the healing abutments.

Esthetic Outcome of Implant Supported Crowns With and Without Peri-Implant Conditioning Using Provisional Fixed Prosthesis: A Randomized Controlled Clinical Trial.

BACKGROUND: Achieving an optimal esthetic result using dental implants is challenging. Fixed implant-supported provisional crowns are often used to customize the emergence profile and to individualize the surrounding peri-implant soft tissue. PURPOSE: The objective of this study is to evaluate whether the use of a provisional implant-supported crown leads to an esthetic benefit on implants that are placed in the esthetic zone. The null hypothesis is that there is no-difference between the two study groups. MATERIAL AND METHODS: Twenty single implants (Bone Level, Straumann AG, Basel, Switzerland) were inserted in consecutive patients. After reopening, a randomization process assigned them to either cohort group 1: a provisional phase with soft tissue conditioning using the "dynamic compression technique" or cohort group 2: without a provisional. Implants were finally restored with an all-ceramic crown. Follow-up examinations were performed at 3 and 12 months including implant success and survival, clinical, and radiographic parameters. RESULTS: After 1 year all implants successfully integrated, mean values of combined modPES and WES were 16.7 for group 1 and 10.5 for Group 2. This was statistically significant. Mean bone loss after 1 year was -0.09 and -0.08 for groups 1 and 2, respectively, without being statistically significant. CONCLUSION: A provisional phase with soft tissue conditioning does improve the final esthetic result.

Esthetic Evaluation of Implant Crowns and Peri-Implant Soft Tissue in the Anterior Maxilla: Comparison and Reproducibility of Three Different Indices.

BACKGROUND: A successful implant reconstruction with optimal esthetics consists of a visually pleasing prosthesis and complete and healthy surrounding soft tissue. In the current literature, numerous indices used to qualitatively assess esthetics have been described. However, studies comparing the indices and their reproducibility are scarce. PURPOSE: The aim of this study was to compare three different esthetic indices for the evaluation of single implant-supported crowns. MATERIALS AND METHODS: A total of 10 prosthodontists (P), 10 orthodontists (O), 10 general dentists (G), and 10 lay people (L) independently performed the same assessment using 30 photographs and corresponding casts with three different esthetic indices (Peri-Implant and Crown Index [PICI], Implant Crown Aesthetic Index [ICAI], "Pink Esthetic Score/White Esthetic Score [PES/WES]) and repeated the evaluations 4 weeks later. RESULTS: The PES/WES and the PICI showed significantly higher esthetic scores (pink, white, total) and clinical acceptance compared with the ICAI in all four groups and in both assessments. The highest intraobserver agreement was achieved using the PES/WES and the least with the ICAI. The mean Kappa per group ranged from 0.18 (group L with ICAI) to 0.63 (group G with PICI). CONCLUSION: In comparison with the ICAI, the PES/WES and PICI were more reproducible. Therefore, PES/WES and PICI seem to be more suitable as esthetic indices for single implant crowns.

Influence of prosthesis type and retention mechanism on complications with fixed implant-supported prostheses: a systematic review applying multivariate analyses.

PURPOSE: To identify the influence of fixed prosthesis type on biologic and technical complication rates in the context of screw versus cement retention. Furthermore, a multivariate analysis was conducted to determine which factors, when considered together, influence the complication and failure rates of fixed implant-supported prostheses. MATERIALS AND METHODS: Electronic searches of MEDLINE (PubMed), EMBASE, and the Cochrane Library were conducted. Selected inclusion and exclusion criteria were used to limit the search. Data were analyzed statistically with simple and multivariate random-effects Poisson regressions. RESULTS: Seventy-three articles qualified for inclusion in the study. Screw-retained prostheses showed a tendency toward and significantly more technical complications than cemented prostheses with single crowns and fixed partial prostheses, respectively. Resin chipping and ceramic veneer chipping had high mean event rates, at 10.04 and 8.95 per 100 years, respectively, for full-arch screwed prostheses. For "all fixed prostheses" (prosthesis type not reported or not known), significantly fewer biologic and technical complications were seen with screw retention. Multivariate analysis revealed a significantly greater incidence of technical complications with cemented prostheses. Full-arch prostheses, cantilevered prostheses, and "all fixed prostheses" had significantly higher complication rates than single crowns. A significantly greater incidence of technical and biologic complications was seen with cemented prostheses. CONCLUSION: Screw-retained fixed partial prostheses demonstrated a significantly higher rate of technical complications and screw-retained full-arch prostheses demonstrated a notably high rate of veneer chipping. When "all fixed prostheses" were considered, significantly higher rates of technical and biologic complications were seen for cement-retained prostheses. Multivariate Poisson regression analysis failed to show a significant difference between screw- and cement-retained prostheses with respect to the incidence of failure but demonstrated a higher rate of technical and biologic complications for cement-retained prostheses. The incidence of technical complications was more dependent upon prosthesis and retention type than prosthesis or abutment material.