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Purpose: To analyze the effect of scanning modes on the accuracy of the Trios intraoral scanner (IOS) for full-arch digital implant impressions. Materials and Methods: The trueness and precision of the intraoral scanning mode (IOSM) and the intraoral edentulous scanning mode (IOEM) of the Trios IOS were evaluated in three edentulous models, each featuring four, six, and eight implant analogs. Reference scanning data were obtained by scanning each model with a desktop scanner. Each model was scanned 10 times using the IOSM and IOEM modes of the Trios IOS to establish the test groups. The scan bodies in the test and reference scans were isolated and exported in the reverse engineering program. The scan bodies in each group were superimposed with the corresponding reference scan (trueness) or with each other (precision). The overall 3D deviation between the aligned scan bodies was computed by the root mean square (RMS) values. Results: No significant difference was found between scanning modes in any of the models. When comparing models, the eight-implant model showed significantly lower trueness than the four-implant model. However, it exhibited significantly higher precision than the four-implant and six-implant models. There were no significant differences in other pairwise comparisons between the models. Conclusions: Trueness and precision values were similar between the IOSM and IOEM groups across all the models. An increase in the number of implants in completely edentulous arches may have a negative impact on digital impression accuracy. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusions Using mini implants as transitional implants (TIs) for complete arch implant‐supported rehabilitations may overcome limitations associated with mucosa‐supported surgical guides and facilitate immediate fixed provisionalization. This study aimed to assess the success of TIs in supporting surgical guides for implant placement and fixed provisional prostheses.Patients who received TIs between 2012 and 2023 for a complete arch implant‐supported prosthesis were evaluated retrospectively. Patient demographic data, TI functionality in supporting a surgical guide and supporting a complete arch provisional prosthesis, and dates of TI placement and regular implant placement were collected. Descriptive statistics were used to determine the survival rate and success rate for TIs.Twenty‐six patients, 35 jaws, 136 TIs, and 216 regular implants were included. The survival rate of TIs was 74.26%; however, the use of TIs yielded success in 97% of jaws for supporting a surgical guide and a fixed complete‐arch provisional prosthesis throughout the complete provisional phase. An average of 4 TIs per maxilla and 3 TIs per mandible supported surgical guides. Thirty‐five provisional prostheses were placed on an average of 4 TIs in the maxilla and 3 TIs in the mandible. Thirty‐four provisional prostheses were successfully supported by TIs and regular implants until final restoration delivery. The survival of regular implants placed in conjunction with the use of TIs was 98%.Using TIs to support a surgical guide and provisional prosthesis may be a predictable approach with a high success rate. All surgical guides planned to be supported on TIs were successful. Despite premature loss or replacement of TIs, this approach was able to support most provisional prostheses until the regular implants could be loaded. [ABSTRACT FROM AUTHOR]

Objective: To assess a newly developed intraoral scan protocol in enhancing the accuracy of complete‐arch implant impressions. Materials and Methods: Four impression approaches were applied to the same maxillary edentulous model with 6 implants: (1) intraoral scan (IOS), (2) intraoral scan with scan aid (IOS‐SA), (3) calibrated intraoral scan protocol (CISP), and (4) conventional splinted open‐tray impression (CONV). Each approach was repeated 10 times, and a direct scan of the model with a desktop scanner was used as a reference model. The alignment of scans and the reference model was conducted by two methods: (a) aligning all scan bodies to evaluate the overall fit, and (b) aligning the first and second scan bodies to simulate the Sheffield fit test for passive fitting of multiple implant‐supported prostheses. Linear deviations from the reference model (trueness) and within each group (precision) were analyzed using Python scripts. Results: When aligned by all scan bodies, the CISP group exhibited comparable mean trueness (38.33 μm) and precision (45.97 μm) to the CONV group (44.30 and 47.92 μm respectively), both of which significantly outperformed the IOS group (86.82 and 83.17 μm, respectively). Furthermore, in the virtual Sheffield fit test, the CISP group achieved the highest levels of mean trueness at the end span (121.7 μm), making a linear deviation reduction of 36.7%, 60%, and 41.4% when compared to the CONV, the IOS, and the IOS‐SA groups, respectively. Moreover, the CISP group (104.3 μm) displayed a remarkable 65, 182, and 86 μm advantage in precision over the CONV, IOS, and IOS‐SA groups, respectively. Conclusion: CISP demonstrated comparable accuracy to the gold standard, the conventional splinted open‐tray impression. Furthermore, it excelled in the virtual passive fitting test. [ABSTRACT FROM AUTHOR]

In this case report, a new modified technique is described for an efficient, simple, and effective digital approach to immediate provisionalization of the implant-supported full-arch prosthesis. Today's patient population is increasingly educated about treatment options and expects efficient, esthetic, and comfortable results. This novel technique delivers on these aims while eliminating the many challenges posed by previously described digital and analog techniques to the immediate provisionalization of the implant-supported full-arch prosthesis. This technique requires minimal chair time and cost to the provider and reduces patient discomfort and complication risk. This technique therefore presents a promising new protocol for this popular procedure. [ABSTRACT FROM AUTHOR]

Objective: To determine the median event-free survival and relative complication rates of monolithic and minimally layered full-arch zirconia prostheses, as well as to identify risk factors for prosthesis complications. Materials and Methods: In this retrospective cohort study, a total of 129 subjects (173 prostheses) were included in the chart review and 56 subjects (75 prostheses) participated in a clinical follow-up visit. All subjects had either single- or dual-arch monolithic or minimally layered zirconia implant-supported prostheses. Data related to patient, implant, and prosthesis factors were extracted from charts. The subgroup that presented for a clinical visit were asked to complete a satisfaction questionnaire. For this subgroup, the following clinical measures were assessed: routine intraoral examination, number of occluding units, cantilever length on each side of the prosthesis (right and left), prosthesis height, occlusal scheme, and oral hygiene methods. Periapical radiographs were obtained when the last radiographs of the patient were taken more than 12 months prior. Results: The follow-up period ranged from 12 months to 7.1 years (mean: 1.9 years). Observed complications included implant loss, peri-implantitis, mucositis, purulence, sinus tract formation, oroantral communication, implant fracture, titanium base debonding, ceramic chipping, prosthetic screw fracture or loosening, damage to opposing teeth, and clicking sounds. There was an insufficient number of complications to evaluate the effect of covariates on the risk of specific complications, such as titanium base debonding (eight events), ceramic chipping (nine events), and peri-implantitis (eight events). The unadjusted event-free median survival time was 5.8 years. The proportion of all prostheses with at least one complication was 30%. There were no observed prosthesis losses during the follow-up period. Conclusion: Monolithic and minimally layered zirconia full-arch implant-supported prostheses demonstrate an acceptable median event-free survival time. Event-free survival times were increased and the number of complications was reduced in prostheses with five to eight implants and conventional (as opposed to zygomatic) implants. There was a reduced hazard of complications with a regular recall regimen. Patient satisfaction with these prostheses was high. [ABSTRACT FROM AUTHOR]

Background: Coaxial implants with an inclined neck might overcome some problems related to angulation of the implant axis when using tilted implants. Therefore, the aim of the present work was to conduct a narrative review of the current literature and to present a case series comparing traditional and coaxial external hex implants in full-arch immediate loading rehabilitations of the maxilla. Methods: A total of 13 external hex tapered implants (Southern Implants) was inserted in the upper jaw of 3 patients. Each patient received two tilted implants in distal sites. In one randomly selected quadrant, the tilted implant was a standard implant, while a Co-Axis® implant with a 24° inclination of the implant shoulder was inserted on the other hemi-arch. Straight conical abutments were screwed on coaxial implants while multiunit abutments of appropriate inclination were screwed as needed on the other implants to correct their axes. Peri-implant bone level was recorded radiographically at T0 (delivery of the immediate loading prosthesis), and at 3, 6, 12, and 24 months of healing and then annually. Plaque index, probing depth, and bleeding on probing were also evaluated. Cumulative implant survival rate (CSR) was calculated, and biological or technical complications were recorded as well as the operator satisfaction towards the use of coaxial implants. Results: The preliminary data collected did not show significant differences in peri-implant tissues health and maintenance over time between the two implant types. No implants failed, and both implant types proved to be favorable for full-arch rehabilitation using tilted implants. Coaxial implants facilitated the prosthodontic procedures. However, a learning curve is required in order to optimize their insertion. Conclusions: Both implants proved to be reliable and suitable for achieving clinical success in full-arch immediate loading rehabilitations, but further research with longer follow-up and larger sample size is needed to confirm these preliminary outcomes. [ABSTRACT FROM AUTHOR]

Accuracy is a necessity in implant impressions to fabricate accurately fitting implant-supported prostheses. This in vitro study aimed to explore the impact of the number of scan bodies on scanning quality by comparing scans of 2 vs 4 implants, and to determine if their accuracy and precision meets acceptable clinical threshold. Two mandibular edentulous models were used: one with 4-parallel implants (4-IM) and the other with 2-parallel implants (2-IM). Each model was scanned 10 times with an intraoral scanner, while reference scans were obtained with a high-precision laboratory scanner. The accuracy of test scans was evaluated by superimposing them onto reference scans and measuring 3D and angular deviations of the scan bodies. To assess the precision, the repeatability of the scans was analyzed by measuring the 3D SDs. Independent t test was used to compare angular deviations, the Mann-Whitney U test was used for 3D deviations and 3D SDs, and 1 sample t test was used for comparing means to the clinical threshold. Angular and 3D deviations were statistically not significant between the 2 groups (P =.054 and 0.143). 3D deviation values were higher than the 150-µm threshold for 2-IM (201 µm) and 4-IM (290 µm); angular deviation in 2-IM was 0.600 degrees and 0.885 degrees for 4-IM. There was no statistically significant difference in the precision of scans between the 2 groups. (P =.161). Although scanning quality improved when 2 scan bodies were used, the difference was not statistically significant. Moreover, full-arch implant scanning did not meet acceptable levels of accuracy and precision. [ABSTRACT FROM AUTHOR]

The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)–printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery. [ABSTRACT FROM AUTHOR]

Worn denture teeth continue to be a significant complication with implant‐supported prostheses. This article discusses a case report that used an intraoral scanning system to restore an existing maxillary implant‐supported prosthesis with significant posterior occlusal wear. IPS e.max (Ivoclar Vivadent, Schaan, Liechtenstein) restorations were fabricated and cemented to the prepared posterior denture teeth to re‐establish the occlusal vertical dimension and to help prevent further wear of the occlusal surfaces. [ABSTRACT FROM AUTHOR]

Objective: Despite the wide clinical use of translucent zirconia for full‐arch implant prostheses, reduced flexural strength and fracture toughness compared with high‐strength opaque zirconia needs to be addressed. A novel proof of concept for FP1 full‐arch prosthesis featured by translucent monolithic zirconia and titanium framework was presented. Clinical Considerations: Computer‐guided implant planning and surgery were executed and digitally designed FP1 temporary prosthesis prefabricated. Implant and prosthetic placement were achieved with a set of three‐dimensional (3D)‐printed templates. Implants were immediately loaded. After 4 months intraoral optical scan was taken to record implant coordinates, soft tissue anatomy, and temporary FP1 prosthesis. A novel digital workflow was used to design and mill overlaying translucent zirconia and anatomically shaped titanium framework with a scalloped soft‐tissue interface. Final FP1 prosthesis was assembled cementing zirconia jacket on titanium counterpart. Conclusions: Translucent zirconia supported by titanium framework can address esthetic and mechanical requirements of FP1 full‐arch prosthesis, minimizing risk of fracture and providing a rigid and passive joint with supporting implants. The smooth and highly polished titanium surface with an anatomic design, tightly matching scalloped soft tissue interface, can limit food impaction, air and saliva leakage and contribute to overall biologic integration of FP1 full‐arch prosthesis. Clinical Significance: Translucent monolithic zirconia featured with anatomically shaped titanium framework with scalloped transmucosal part, combining a pleasant esthetic outcome with increased flexural strength and fracture toughness, may be indicated to increase the clinical performance of FP1 full‐arch prosthesis. [ABSTRACT FROM AUTHOR]

The objective of the present retrospective multi-center study was to analyze the outcomes of bone-level (BL) implants and tissue-level (TL) implants in immediate-loading full-arch rehabilitations. Patients who were previously rehabilitated with full-arch immediate-loading rehabilitations with either BL or TL implants were considered. Data regarding implant survival rate, marginal bone loss (MBL), peri-implant probing depth (PPD), plaque index (PI), and bleeding on probing (BOP) were recorded, and the 1-year follow-up data were statistically analyzed between the two groups. In total, 38 patients were evaluated for a total implant number of 156 (n = 80 TL implants and n = 76 BL implants). An implant survival rate of 97.37% was recoded for the BL group while an implant survival rate of 100% was noted for the TL group. A total MBL of 1.324 ± 0.64 mm was recorded for BL implants, while a total MBL of 1.194 ± 0.30 mm was recorded for TL implants. A statistically significant difference was highlighted regarding MBL at the mesial aspect (p = 0.01552) of the implants, with BL implants presenting with higher MBL. Within the range of acceptable healthy values, a statistically significant difference was also highlighted regarding BOP (p < 0.00001), with TL implants presenting higher values. No statistically significant difference (p > 0.05) was recorded for any of the other variables analyzed. Within the limitations of the present retrospective study, both TL and BL implants seem to provide good clinical outcomes after a 12-month observational period when employed in immediate-loading full-arch rehabilitation.

Abstract Purpose Increasing scientific evidence support extending the application of short dental implants to non-atrophic dental arches. The purpose of this study has been the evaluation of extra-short implants (≤ 6.5 mm in length) that were placed in atrophic and non-atrophic anatomical sites to support the same prosthesis. Methods For that, a retrospective study was conducted by including complete dentures that were solely supported by extra-short implants in the maxilla and/or the mandible. Clinical data about patients, implants, anatomy, and prosthesis were obtained. Statistical analysis was performed to assess implant- and prosthesis-survival, changes in the marginal bone level and prosthetic complications. Results A total of 87 implants in 15 screw-retained complete dentures were assessed. None of the prostheses nor the extra-short implant failed during the follow-up of 27.2 ± 15.4 months. The changes in the mesial and distal marginal bone level were + 0.15 ± 0.51 mm and + 0.11 ± 0.50 mm, respectively. Comparing the implants according to the availability of sufficient bone to place longer implants, indicated the absence of significant differences in the changes of the mesial marginal bone level. However, the changes in the distal marginal bone level showed a statistically significant difference in favor of implants that were placed in non-atrophic sites. Two events of screw loosening were reported that were resolved by retightening the screws. Conclusions Implant- and prosthesis-related outcomes support the use of extra-short implants in atrophic and non-atrophic site to support complete prosthesis. Graphical Abstract

The objective of the present retrospective multi-center study was to analyze the outcomes of bone-level (BL) implants and tissue-level (TL) implants in immediate-loading full-arch rehabilitations. Patients who were previously rehabilitated with full-arch immediate-loading rehabilitations with either BL or TL implants were considered. Data regarding implant survival rate, marginal bone loss (MBL), peri-implant probing depth (PPD), plaque index (PI), and bleeding on probing (BOP) were recorded, and the 1-year follow-up data were statistically analyzed between the two groups. In total, 38 patients were evaluated for a total implant number of 156 (n = 80 TL implants and n = 76 BL implants). An implant survival rate of 97.37% was recoded for the BL group while an implant survival rate of 100% was noted for the TL group. A total MBL of 1.324 ± 0.64 mm was recorded for BL implants, while a total MBL of 1.194 ± 0.30 mm was recorded for TL implants. A statistically significant difference was highlighted regarding MBL at the mesial aspect (p = 0.01552) of the implants, with BL implants presenting with higher MBL. Within the range of acceptable healthy values, a statistically significant difference was also highlighted regarding BOP (p < 0.00001), with TL implants presenting higher values. No statistically significant difference (p > 0.05) was recorded for any of the other variables analyzed. Within the limitations of the present retrospective study, both TL and BL implants seem to provide good clinical outcomes after a 12-month observational period when employed in immediate-loading full-arch rehabilitation. [ABSTRACT FROM AUTHOR]

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Background: Coaxial implants with an inclined neck might overcome some problems related to angulation of the implant axis when using tilted implants. Therefore, the aim of the present work was to conduct a narrative review of the current literature and to present a case series comparing traditional and coaxial external hex implants in full-arch immediate loading rehabilitations of the maxilla. Methods: A total of 13 external hex tapered implants (Southern Implants) was inserted in the upper jaw of 3 patients. Each patient received two tilted implants in distal sites. In one randomly selected quadrant, the tilted implant was a standard implant, while a Co-Axis® implant with a 24° inclination of the implant shoulder was inserted on the other hemi-arch. Straight conical abutments were screwed on coaxial implants while multiunit abutments of appropriate inclination were screwed as needed on the other implants to correct their axes. Peri-implant bone level was recorded radiographically at T0 (delivery of the immediate loading prosthesis), and at 3, 6, 12, and 24 months of healing and then annually. Plaque index, probing depth, and bleeding on probing were also evaluated. Cumulative implant survival rate (CSR) was calculated, and biological or technical complications were recorded as well as the operator satisfaction towards the use of coaxial implants. Results: The preliminary data collected did not show significant differences in peri-implant tissues health and maintenance over time between the two implant types. No implants failed, and both implant types proved to be favorable for full-arch rehabilitation using tilted implants. Coaxial implants facilitated the prosthodontic procedures. However, a learning curve is required in order to optimize their insertion. Conclusions: Both implants proved to be reliable and suitable for achieving clinical success in full-arch immediate loading rehabilitations, but further research with longer follow-up and larger sample size is needed to confirm these preliminary outcomes.

Purpose: To test a novel implant metal-acrylic prosthesis design in comparison to a conventional prosthesis design through simulation of cyclic masticatory loading. The novel design involved digital designing and fabrication of the framework and the matched veneering acrylic resin material. Materials and Methods: Ten prostheses were fabricated for each group. All the prostheses exhibited a similar external design on two implants with a distal cantilever. The conventional group comprised a milled metal framework with mechanically retained acrylic denture teeth via vertical pins. The digital prosthesis group incorporated an inverted T-shape bar and a monolithic milled acrylic resin veneer. The resin veneer was subsequently adhesively attached on the bar. All prostheses were thermally aged and subjected to laboratory cyclic loading at the cantilever region. The load-to-failure and the number of cycles until failure were collected. Furthermore, failed specimens were analyzed to determine the mode of failure. Results: The digital prostheses failed at significantly greater load-to-failure (1,570.0 N ± 116.0 N) and number of cycles (124,857 ± 21,608) than the conventional prostheses (load-to-failure = 1,015.0 N ± 47.4 N; number of cycles = 28,452 ± 6,559). The conventional prostheses failed by fracturing of the acrylic teeth and veneering material that led to exposure of the metal framework. Half of the digital prostheses failed by superficial chipping of the veneering material, while the other half failed by the deformation and fracture of screws. Conclusion: Within the limitations of this study, the digital prostheses with the novel design and monolithic veneering material showed significantly higher strength compared with the conventional prostheses. The mode of acrylic failure of the digital prostheses was more favorable. [ABSTRACT FROM AUTHOR]

Purpose: Increasing scientific evidence support extending the application of short dental implants to non-atrophic dental arches. The purpose of this study has been the evaluation of extra-short implants (≤ 6.5 mm in length) that were placed in atrophic and non-atrophic anatomical sites to support the same prosthesis. Methods: For that, a retrospective study was conducted by including complete dentures that were solely supported by extra-short implants in the maxilla and/or the mandible. Clinical data about patients, implants, anatomy, and prosthesis were obtained. Statistical analysis was performed to assess implant- and prosthesis-survival, changes in the marginal bone level and prosthetic complications. Results: A total of 87 implants in 15 screw-retained complete dentures were assessed. None of the prostheses nor the extra-short implant failed during the follow-up of 27.2 ± 15.4 months. The changes in the mesial and distal marginal bone level were + 0.15 ± 0.51 mm and + 0.11 ± 0.50 mm, respectively. Comparing the implants according to the availability of sufficient bone to place longer implants, indicated the absence of significant differences in the changes of the mesial marginal bone level. However, the changes in the distal marginal bone level showed a statistically significant difference in favor of implants that were placed in non-atrophic sites. Two events of screw loosening were reported that were resolved by retightening the screws. Conclusions: Implant- and prosthesis-related outcomes support the use of extra-short implants in atrophic and non-atrophic site to support complete prosthesis. [ABSTRACT FROM AUTHOR]

Purpose: There is a paucity of comparative clinical studies assessing the accuracy of full‐arch digital scans versus conventional implant impressions. The aim of this retrospective study was to compare the three‐dimensional (3D) deviations between full‐arch digital scans and conventional implant impressions for edentulous maxillae and mandibles. Materials and methods: Twenty‐seven patients (36 edentulous jaws) were treated with one‐piece, screw‐retained implant‐supported fixed complete dental prostheses (IFCDPs). Twenty‐one jaws were maxillary, and 15 were mandibular. Full‐arch conventional impressions and intraoral digital scans with scan bodies and an intraoral scanner had been taken during the impression phase. Following verification of the conventional stone casts, the casts were digitized. The generated standard tessellation language (STL) files from both impression techniques were merged and analyzed with reverse engineering software. The primary aim was to evaluate the accuracy between conventional and digital full‐arch scans, while the effect of the edentulous jaw in 3D accuracy was the secondary aim. Results: The cumulative 3D (mean ± SD) deviations between virtual casts from intraoral full‐arch digital scans and digitized stone casts generated from conventional implant impressions were found to be 88 ±24 μm. In the maxillary group, the mean ± SD 3D deviation was 85 ±25 μm, compared to 92 ±23 μm for the mandibular group (p = 0.444). Conclusion: The 3D implant deviations found between the full‐arch digital and conventional impressions lie within the clinically acceptable threshold. No statistically significant difference was identified between maxillary and mandibular jaws in terms of 3D deviations. [ABSTRACT FROM AUTHOR]

Objectives: To compare the cleaning efficacy of glycine air polishing against two different professional oral hygiene techniques on implants supporting full-arch fixed prostheses. Method and materials: Thirty patients with a total of 32 implant fixed fullarch rehabilitations in the maxilla and/or man dible (134 implants) were included. After the removal of the screw-retained prostheses, baseline peri-implant spontaneous bleeding (SB), Plaque Index (PI), probing depth (PD), and bleeding on probing (BOP) were recorded (T0). Three oral hygiene treatments were assigned randomly following a split-mouth method: all the patients received glycine air polishing (G) in one side of the arch (n = 32), and sodium bicarbonate air polishing (B) (n = 16) or manual scaling with carbon-fiber curette (C) (n = 16) was performed in the opposite side. After the hygiene procedures, PI and SB were recorded and patient's comfort degree towards the three techniques was analyzed by questionnaires using a rating scale from 1 to 5 (T1). Results: PI reduction was significantly higher for G (T0, 2.88 ± 1.37; T1, 0.04 ± 0.21) and B (T0, 3.13 ± 1.34; T1, 0.0 ± 0.0) as compared with C (T0, 2.15 ± 1.46; T1, 0.44 ± 0.7) (P < .001). B reported the highest mean value of SB (T0, 0.0 ± 0.0; T1, 3.42 ± 0.75) compared with G (T0, 0.05 ± 0.21; T1, 1.60 ± 1.05) and C (T0, 0.07 ± 0.24; T1, 0.73 ± 0.91) (P < .001). A significant difference in comfort mean score was found between G (4.8 ± 0.5) and B (3.5 ± 1.7) (P = .014), no difference between G and C (4.7 ± 0.7) (P = .38). Conclusion: Professional oral hygiene on implants using glycine air polishing showed high levels of both cleaning efficacy and patients' acceptance. [ABSTRACT FROM AUTHOR]

With the aging of the population and the increase in the number of edentulous patients, implant-supported fixed restorations have become more prevalent in clinical treatment. It is necessary to assess the patient's remaining bone and occlusal situation correctly; the upper jaw usually needs 6 to 8 implants, whereas the lower jaw needs 4 to 6 implants. Patients with severe alveolar bone atrophy can adopt the "all-on-4/6" treatment plan, short implants, and zygomatic and pterygomaxillary implants to avoid complex bone grafting and remain cautious when the surgical procedures require more surgical experience. According to the repair methods, the superstructure can be divided into one-piece repair and segmental repair. One-piece repair has a lower implant number, flexible location, and reasonable stress distribution but a high maintenance cost. Sectional repair easily achieves passive placement, convenient cleaning, and maintenance in the late stages, but implants need quantity and high requirements for alveolar bone. However, the requirements for alveolar bone and implant number are high. Mutually protected occlusion with minimal or no cantilever on provisional prosthesis is recommended.

Purpose: The anterior‐posterior spread concept is relied upon to understand the bioengineering aspects of cantilevers in fixed complete denture prostheses. This concept is not evidence‐based. With no other category existing in contemporary implant dentistry, this conventional anterior‐posterior spread concept may have limited more precise and accurate biomechanical analysis. This paper aims to validate a scientific rationale for utilizing this new prosthesis‐implant arch area ratio instead of the preexisting anterior‐posterior spread concept. Materials and methods: Utilizing the preexisting mathematical principle of "Heron's formula," enabling the calculation of the area of a triangle with three known lengths and no angular information, a new prosthesis‐implant arch area ratio is introduced through algebraic derivation. Geometrically, three different sections of prosthetic cantilevers are defined as: (1) anterior cantilever; (2) lateral cantilever; (3) posterior cantilever. The prosthesis‐implant arch area ratio is defined as the prosthesis arch area (anterior, lateral, or posterior cantilever) divided by the sum of the platform arch area and the selected prosthesis arch area. As a proof‐of‐concept experiment, fifteen different laboratory cast arches (n = 15) were chosen; theorized four implant platforms were referenced from the conventional anterior‐posterior spread ration of 1:1.5, followed by calculating platform arch area and prosthesis arch area using Heron's formula. Then, three different horizontal arch width ratios (1:1, 1.25:1, and 1.5:1) under the constant linear height ratio of anterior‐posterior spread (1:1.5) were drawn to assign different experimental groups of prosthesis arch area on each patient scenario, followed by cantilever comparison combining all ratio values (n = 45). One‐way ANOVA and Tukey's post hoc multiple comparison tests were used for statistical analysis. Results: One‐way ANOVA revealed statistical differences of all prosthesis‐implant arch area ratios on each cantilever group; anterior cantilever, F(2, 42) = 8.326, p = 0.0009; lateral cantilever F(2, 42) = 43.92, p < 0.0001; posterior cantilever, F(2, 42) = 26.66, p < 0.0001, as well as cantilever's comparison, F(2, 132) = 240.8, p < 0.0001. Tukey's post hoc test showed a statistically significant ascending trend of prosthesis‐implant arch area ratio as the horizontal width ratio increases. Interestingly, the posterior cantilever had the greatest prosthesis‐implant arch area ratio. Conclusions: Compared to the preexisting anterior‐posterior spread concept, a new prosthesis‐implant arch area ratio seemed to be a more categorized, geometric, and perceptive modality of assessing the prosthetic cantilever in a full‐arch implant‐supported prosthesis, allowing a more systematic indexing of different full‐arch implant clinical scenarios with greater specificity and consistency. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study was to investigate the accuracy of a new digital impression system, comparing it to the plaster impression technique in the realization of full-arch implant-supported metal frameworks. Methods: We took 11 scans (8 of the upper maxilla and 3 of the lower jaw) on a sample of nine patients previously rehabilitated with fixed full-arch screw-retained prostheses following the Columbus Bridge Protocol (CBP) with four to six implants (total: 51) since at least 4 months. Two impressions were taken for each dental arch: one analogic plaster impression using pick-up copings and an open tray technique and a second one using an intra-oral scanner. Two milled metal substructures were realised. The precision and passivity of the substructures were clinically analysed through the Sheffield test and endo-oral radiographs. Laboratory scans of the plaster casts obtained from an intra-oral scanner (IOS) and of the plaster casts obtained from traditional impression were compared with the intraoral scans following Hausdorff's method and an industrial digital method of optical detection to measure discrepancies. A Mann–Whitney test was performed in order to investigate average distances between surfaces after the superposition. Results: The Sheffield test demonstrated an excellent passivity of the frameworks obtained through both the digital and the analogic method. In 81.81% of cases (n = 9) both substructures were found to have a perfect fit with excellent passivity, while in 18.18% (n = 2) of cases the substructures were found to have a very slight discrepancy. From the radiographic examination, no gaps between the frameworks and the implant heads or multiunit abutments were observed, with 100% accuracy. By superimposing digital files of scans according to Hausdorff's method, a statistically significant discrepancy (p = 0.006) was found between the digital scans and the digital models obtained from plaster impressions. Three-dimensional optical detection found a mean discrepancy of 0.11 mm between the analogic cast and the cast derived from the digital impression. Conclusions: The present study clinically demonstrates that milled implant-supported full-arch frameworks obtained through a digital scan and the herein described technique have an accuracy comparable to those obtained with traditional plaster impression. [ABSTRACT FROM AUTHOR]

This technique report describes an alternative method to stabilize surgical templates throughout full‐arch static computer‐assisted implant surgery (FA s‐CAIS). In FA s‐CAIS, remaining teeth, mucosa, existing implants, custom occlusal device, bone, or any combination thereof, could be used as an initial positioning mechanism to position surgical templates. Different anchoring mechanisms are then used to stabilize the surgical templates during surgery. In this report, a novel design of surgical templates using remaining dentition and opposing occlusal surfaces as initial positioning mechanism followed by the combination of bone block fixation screw and stainless‐steel beads as secondary anchoring mechanisms is described. The advantages, limitations, and comparisons with surgical templates using other anchoring mechanisms are also discussed. [ABSTRACT FROM AUTHOR]

Pterygoid implant placement has been proven to be a viable option in full-arch implant rehabilitation for extremely atrophic maxillae. Nevertheless, the utilization of pterygoid implants remains a challenge for the dentist due to the difficulties of accessing the surgical site and poor visibility. To address these difficulties, digital techniques have been used to enhance the accuracy of pterygoid implant placement. This clinical case describes the application of an autonomous robot system to enhance the precision and efficacy of pterygoid implant placement. The results demonstrated that the integration of automation and real-time imaging provided by the robot system significantly improved the safety and accuracy of the surgical procedure., (© 2024 by the American College of Prosthodontists.)

Although there are difficulties with using intraoral scans for implant-supported complete-arch fixed dental prostheses (ISCFDPs), several commercially available systems have become helpful in simplifying the treatment process in the prosthetic phase. These systems help patients move from interim ISCFDPs to receiving definitive prostheses in just three clinical visits. This clinical report summarizes the indications, benefits, and limitations of the four systems. The information provided in this report about the digital prosthetic workflow of ISCFDPs aims to help clinicians make well-informed choices and improve treatment results. With digital technologies advancing, refining these tools and protocols, and validating research is crucial for continued evolution in the field., (© 2024 The Author(s). Journal of Prosthodontics published by Wiley Periodicals LLC on behalf of American College of Prosthodontists.)

Objectives: The purpose of this systematic review was to compare the accuracy of digital and conventional full-arch impressions in vivo. Materials and methods: This systematic review was conducted according to the PRISMA and registered at the PROSPERO (CRD42021232736). Electronic and hand searches were performed to identify in vivo studies comparing the linear or 3D accuracy of digital and conventional impressions. The risk of bias (ROB) of included studies was assessed by QUADAS-2, and the overall quality of evidence was assessed by GRADE. Results: Twenty-two studies met the inclusion criteria, and 13 studies were included in the meta-analysis. There was no significant difference between digital and conventional impressions in the linear measurements of tooth width, anterior Bolton ratio, overall Bolton ratio, intercanine distance (ICD), and intermolar distance (IMD). The repeated measurement mean errors (RMEs) were less than 0.1 mm, the intra-examiner intraclass correlation coefficient (ICC) values were more than 0.9, and the inter-examiner ICC values were more than 0.87 for both impression techniques. The 3D deviation between digital and alginate impressions was 0.09 mm. The 3D precision of both impression techniques was less than 0.1 mm. Conclusions: The trueness of digital and alginate full-arch impressions was similar, and both impression techniques showed high precision. More research was needed to compare digital impressions and other conventional impression materials. Clinical relevance: For patients with completely natural dentition, the digital impressions obtained directly from intraoral scanning can be considered a viable alternative to alginate impressions. [ABSTRACT FROM AUTHOR]

The rehabilitation of full-arches with implant-supported prostheses is a widespread practice in implant dentistry. However, some cases require additional techniques to solve the same clinical case. The purpose of this case report is to present a maxilla total rehabilitation with implant-supported prosthesis in a patient with vertical maxillary excess requiring osteotomy, which was performed with piezoelectric to remove the bone platform, providing the patient with better esthetics and prosthetic space for proper hygiene and maintenance of the prosthesis. [ABSTRACT FROM AUTHOR]

Traditional techniques for fabricating interim, immediately loaded implant-supported fullarch prostheses are complex and time-consuming. The present study presents an efficient technique for fabricating interim prostheses with prefabricated multipurpose rigid connecting bars. This technique can minimise the misfit attributed to the polymerisation shrinkage of resin and expansion of the working cast, and simultaneously facilitate impression taking and occlusal records in one visit, thus reducing laboratory and chair time. Due to its ease of use and clinical efficiency, the present technique is considered particularly beneficial for immediate loading rehabilitation. [ABSTRACT FROM AUTHOR]

Abstract Background With the emergence of three-dimensional (3D) integration technology, analysis of soft tissue displacement and morphological changes after maxillary full-arch implant-supported fixed prostheses can be performed. The aim of this study was to verify the feasibility of the 3D integration method for constructing the relative position of the prostheses and facial soft tissue, evaluate the displacement and morphological variation of the upper lips after maxillary full-arch implant-supported fixed prostheses. Methods Twenty-five maxillary edentulous patients were recruited in this study. At the time of final prosthesis delivery, the 3D prostheses data and three 3D facial profiles were integrated. After method validation, the 3D position changes of seven soft tissue landmarks were used to reflect the 25 upper lips. The variation of four morphological distances were analyzed to reflect the morphological alteration of the upper lips. Two pairs of dentofacial landmarks were used to analyze the sagittal relative position of the prostheses and soft tissue. The included patients were also grouped to determine the impact of sex, upper lip thickness, and length on lip support changes. Results The average distance of the two matched relative reliable forehead regions was only 0.32 mm. The sagittal shifts of labrale superius (LS), stomion (STO), crista philtri left (CPHL) and crista philtri right (CPHR) were 3.44 ± 1.39 mm, 2.52 ± 1.38 mm, 3.04 ± 1.18 mm, and 3.12 ± 1.21 mm, respectively. With the exception of the decrease in the length of subnasale (SN)-LS, the length of cheilion right (CHR)-cheilion left (CHL), CPHR-CPHL, and LS-STO significantly increased. The two pairs of dentofacial landmarks had strong positive movement correlations along the sagittal direction. Patients with thinner and longer lips showed more lip support than those with thicker and shorter lips by a clinically insignificant amount. Conclusions The integration method of 3D facial and dental data showed high repeatability in constructing the dentofacial relative position. The linear equations reflecting dentofacial relative position could aid clinicians in evaluating the restoration effect and estimate the upper lip variation.

Objectives: To evaluate the efficacy of implant-supported in comparison to tooth-supported full-arch prostheses in patients with stage IV periodontitis. Materials and Methods: Systematic electronic search (CENTRAL/MEDLINE/SCOPUS) up to March 2020 was conducted to identify randomized controlled trials and cohort-like studies comparing/evaluating fixed full-arch rehabilitation on teeth or implants in patients with stage IV periodontitis. The primary outcome measure was loss of teeth/implants and restorations. Data extraction was performed to create evidence tables, and meta-analyses were carried out as appropriate. Results: A total of 26 studies (31 publications) were identified but none addressed the scientific question in a controlled and randomized design. The risk of bias throughout the included studies was judged to be high, and meta-analyses demonstrated a high degree of heterogeneity. Mean-weighted observation periods in studies on toothsupported restorations were significantly longer than in studies on implant-supported restorations. The predicted loss of teeth and tooth-supported full-arch restorations over 10 years was 1% and 5%, respectively. The 15-year estimates were 10% and 13%. Corresponding predictions for implants and implant-supported restorations for 10 years amounted to 4% and 6%, respectively. Technical complications were the most commonly reported and affected 8% of tooth-supported restorations (during 7.2 years) and 42% of implant-supported structures (during 2.6 years). Peri-implantitis- or peri-implantitis-like symptoms were observed at an estimated 9% of implants (after 3.1 years). Conclusions: Based on observational studies on full-arch rehabilitation of stage IV periodontitis patients, 10-year estimates of tooth loss were lower than the corresponding estimates for implants. Estimated loss of tooth- and implantsupported restorations at 10 years was similar. Technical complications were more prevalent at implant-supported when compared to tooth-supported restorations. [ABSTRACT FROM AUTHOR]

Objective: Information about full-digital protocols for bite registration with intraoral scanners on multiple implants in the edentulous jaw is scarce. The purpose of this comparative in vivo study was to investigate the reliability and time efficiency of a novel full-digital bite registration technique for the manufacture of full-arch maxillary fixed implant prostheses. Material and methods: In ten patients, a full-arch maxillary fixed implant prosthesis was manufactured on multi-unit abutment level through an analog prosthetic workflow. The bite registration was performed with use of a screw-retained polymethyl methacrylate (PMMA) verification jig with detachable wax rim. To articulate the definitive edentulous maxillary implant cast in centric relation at the appropriate occlusal vertical dimension (OVD) to the mandibular antagonist cast, a type II articulator (Artex, Amann Girrbach) was used. Three to six months later, a full-digital bite registration was performed with use of dual-function scan bodies and bilateral connected bite pillars. The bite pillars screwed into the scan bodies were used to adjust and articulate the edentulous maxillary implant arch to the mandibular antagonist arch at the defined OVD. Treatment time for analog and digital bite registration technique was measured in each patient. The reliability of the digital bite registration technique was evaluated by 3D comparison of two sets of stereo lithographic (STL) files obtained from each patient. The three-dimensional deviation was defined along the X-, Y- and Z-axes (Geomagic Control X, 3D Systems Inc., Rock Hill, SC, USA). Results: The treatment time for digital bite registration using dual-function scan bodies and bite pillars was significantly shorter than analog bite registration with verification jig and wax rim (60.30%, SD 5.72%). Minor differences between the two techniques were observed with a linear deviation range of 1115 µm (SD 668 µm) overall, 46.2 µm (SD 731.3 µm) along the X-axis, −200.3 µm (SD 744.3 µm) along the Y-axis and 67.1 µm (SD 752.2 µm) along the Z-axis. Bilateral balanced contacts were registered in all patients during full-digital bite registration. Conclusions: The novel digital bite registration technique with dual-function scan bodies and bite pillars allows for a full-digital workflow for full-arch implant supported restorations. The digital bite workflow was 60% faster, and the overall deviation was around 1 mm, which can be considered clinically acceptable. [ABSTRACT FROM AUTHOR]

Background: There is a need for a long-term evidence of implants placed in challenging conditions. The aim of this study was to investigate the outcome of full-arch rehabilitations with the All-on-4 concept for implants inserted with dehiscence or fenestrations. Methods: This retrospective cohort study included 123 patients (dehiscence, n = 87 patients; fenestrations, n = 28 patients; both conditions, n = 8 patients), with a total of 192 implants in immediate function presenting dehiscence (n = 150), fenestrations (n = 40), or both conditions (n = 2). Primary outcome measures were cumulative implant survival (CSurR) and success (CSucR) rates. Secondary outcome measures were prosthetic survival, marginal bone loss, and incidence of biological complications. Results: CSurRs were 94.1% (overall), 95.6% (dehiscence), and 88.1% (fenestrations) at 10 years using the patient as the unit of analysis. Smoking affected implant failure significantly (p = 0.019). Implant-level CSurRs and CSucRs at 10 years were 96.2% and 93.5% (overall), 97.2% and 94.6% (dehiscence), and 90.0% and 87.6% (fenestrations), respectively. Average bone resorption at 5 and 10 years was 1.22 mm and 1.53 mm, respectively. Biological complications occurred in 18 patients (n = 18 implants). Conclusions: Implants inserted with dehiscence or fenestrations demonstrate good long-term outcomes with overall high success and survival rates and low average marginal bone resorption, despite an inferior outcome in implants with fenestrations and smoking's negative effect. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the immediate function of anterior maxillary implants.Methods: One hundred nine patients (42 males and 67 females; average age 55.2 years; range 38-81 years) were followed for 10 years. One hundred eighty-eight implants using nasal and full-length palatine cortical anchorage were inserted in the anterior section of the maxilla together with 188 tilted implants placed posteriorly. Outcome measures were implant success and survival, prosthesis survival, bone loss, and the incidence of biological and mechanical complications. Cumulative success and survival were computed through Kaplan-Meyer product limit estimator (at patient level) and life tables (implant level).Results: Four patients lost one implant each, giving a 10-year cumulative survival rate of 95.8% and 97.7% using the patient and the implant as the unit of analysis, respectively. The prosthesis survival rate was 98.2%, and the average marginal bone loss was 1.79 mm (1.06 mm). The cumulative success rate was 89.1% and 92.5% using the patient and the implant as the unit of analysis, respectively.Conclusion: Full-arch fixed prosthetic rehabilitations supported by immediately functional implants inserted in the anterior maxilla with bicortical anchorage together with posterior-tilted implants are viable in the long term. [ABSTRACT FROM AUTHOR]

The manufacture of complete‐arch fixed implant prostheses requires many technical steps to ensure a successful outcome. With the use of monolithic materials such as zirconia, the design of the prosthesis is crucial for a superior result. The aim of this article is to outline a combined technique using a CAD/CAM software for the manufacture of fixed implant prosthesis prototypes for complete‐arch implant rehabilitations, which can be done in‐house with minimal equipment. This makes it accessible and feasible for those who wish to be involved in the design phase of such prostheses. The method involves collecting several 3D data files including the patient's current prosthesis, the definitive cast, occlusal records and photographs. The technique is described using a patient case that has been provided with digitally designed and in‐house manufactured prototypes. [ABSTRACT FROM AUTHOR]

Introductions: Intraoral scanner has been widely used for implant impression in partially edentulous cases; however, its accuracy in the impression of full‐arch implant is still questionable. Clinical report: This clinical report presents a technique to check the accuracy of intraoral scanning for complete‐arch implant restorations using an implant index cast (The Glossary of Prosthodontic Terms 9th Edition) and a three‐dimensional printed cast. A clinical case of immediate loading on a maxillary edentulous patient illustrates the application of an implant index cast in implant fixed complete dentures (IFCDs). Discussion: The implant index cast was fabricated based on the immediate interim prosthesis and provides effective control of the fit of scanned files and printed models. Therefore, this approach allows a more predictable and accurate fit of the final prosthesis. Clinical significance: In this article, we present a technique to check the accuracy of the final prosthesis without the need for a conventional impression and final cast in a digital workflow. This proposed approach is demonstrated through a case report of a maxillary edentulous patient restored with immediate loaded IFCDs. [ABSTRACT FROM AUTHOR]

Purpose: Long-term success of titanium dental implants is influenced by various factors, including the maintenance of good oral hygiene. The present study aimed to evaluate cleaning effectiveness and patient satisfaction with glycine powder air polishing and traditional professional oral hygiene treatments when applied to implant-supported full-arch restorations without removal of the fixed prosthesis. Materials and methods: A total of 85 patients with 357 implants supporting full-arch fixed restorations were included. After removal of the prosthesis (T0), the following parameters were recorded: Plaque Index, peri-implant spontaneous bleeding, probing depth and bleeding on probing. The prosthesis was then reinserted. The patients were divided into three groups, each of which received two hygiene therapies randomly administered in each hemiarch using a splitmouth design. The possible treatments were glycine powder air polishing and use of sponge floss vs sponge floss only in group 1; glycine powder air polishing vs use of an ultrasonic device with a polyetheretherketone fibre tip coating in group 2; and glycine powder air polishing vs use of carbon fibre curettes and sponge floss in group 3. After instrumentation, the prostheses were removed to assess the Plaque Index and peri-implant spontaneous bleeding. Questionnaires were used to record patients' levels of comfort and satisfaction in relation to the various treatments. Results: Glycine powder air polishing resulted in a significantly higher reduction in plaque around implants compared to control treatments (sponge floss only, ultrasonic device with polyetheretherketone fibre tip coating, and manual scaling with carbon fibre curettes and use of sponge floss) (P = 0.020). Glycine powder air polishing followed by application of sponge floss provided the greatest reduction of plaque deposits on the prosthetic surfaces. On average, 80% of patients rated glycine powder air polishing highest with regard to satisfaction. Conclusions: Glycine powder air polishing is a highly effective and comfortable treatment to maintain good oral hygiene in clinical practice, and could be used as an alternative to manual and mechanical instrumentation when dealing with implant-supported restorations. [ABSTRACT FROM AUTHOR]

Background: With the emergence of three-dimensional (3D) integration technology, analysis of soft tissue displacement and morphological changes after maxillary full-arch implant-supported fixed prostheses can be performed. The aim of this study was to verify the feasibility of the 3D integration method for constructing the relative position of the prostheses and facial soft tissue, evaluate the displacement and morphological variation of the upper lips after maxillary full-arch implant-supported fixed prostheses. Methods: Twenty-five maxillary edentulous patients were recruited in this study. At the time of final prosthesis delivery, the 3D prostheses data and three 3D facial profiles were integrated. After method validation, the 3D position changes of seven soft tissue landmarks were used to reflect the 25 upper lips. The variation of four morphological distances were analyzed to reflect the morphological alteration of the upper lips. Two pairs of dentofacial landmarks were used to analyze the sagittal relative position of the prostheses and soft tissue. The included patients were also grouped to determine the impact of sex, upper lip thickness, and length on lip support changes. Results: The average distance of the two matched relative reliable forehead regions was only 0.32 mm. The sagittal shifts of labrale superius (LS), stomion (STO), crista philtri left (CPHL) and crista philtri right (CPHR) were 3.44 ± 1.39 mm, 2.52 ± 1.38 mm, 3.04 ± 1.18 mm, and 3.12 ± 1.21 mm, respectively. With the exception of the decrease in the length of subnasale (SN)-LS, the length of cheilion right (CHR)-cheilion left (CHL), CPHR-CPHL, and LS-STO significantly increased. The two pairs of dentofacial landmarks had strong positive movement correlations along the sagittal direction. Patients with thinner and longer lips showed more lip support than those with thicker and shorter lips by a clinically insignificant amount. Conclusions: The integration method of 3D facial and dental data showed high repeatability in constructing the dentofacial relative position. The linear equations reflecting dentofacial relative position could aid clinicians in evaluating the restoration effect and estimate the upper lip variation. [ABSTRACT FROM AUTHOR]

Background: Discordant opinions have emerged among clinicians and researchers regarding a digital impression for full-arch implant-supported fixed dental prostheses (FDPs). The purpose of this study was to assess the fit of screw-retained milled frameworks on six implants realized from digital impressions through the Sheffield test. Methods: One patient received a maxillary full-arch implant-supported FDP. Six months after the surgical procedure, ten intraoral full-arch digital impressions were performed to mill ten frameworks. To clinically assess the fit, the Sheffield test was applied for all frameworks. The gaps among the frameworks and the implant analogs were measured using a microscope on the master model realized with a traditional impression. The Wilcoxon sum-rank test was used to compare the misfit value among the different implant positions. Results: The Sheffield test did not show gaps in the framework–implant interfaces when the screw was completely tightened on the more distal implant for all the milled frameworks. The mean misfit value calculated after microscope examination was 38 ± 5 μm. Differences that were statistically significant emerged when the misfit values of central positions were compared with other values. Conclusions: The use of full-arch implant digital impressions represents a viable alternative to traditional impressions for the fabrication of implant-supported FDPs. [ABSTRACT FROM AUTHOR]

Objective: To assess clinical and radiological performance of novel digital workflow integrating dynamic guided surgery, to streamline execution of implant placement, soft and bone tissue sculpturing, and immediate delivery of navigation guided complete‐arch prosthesis. Materials and Methods: This proof of concept prospective single cohort study investigated 10 consecutive patients (three males, seven females; mean age 62.5 ± 8.9 years; range, 48–75) requiring at least one complete‐arch fixed dental prostheses (FDP) in both jaws, treated between January and August 2019. Primary outcomes were implant and prosthetic success rates, surgical and prosthetic complications. Secondary outcomes were marginal bone loss (MBL), implant stability quotient (ISQ), periodontal parameters (plaque and bleeding indexes). Results: Sixty implants (32 NobelParallel TiUltra and 28 NobelActive TiUltra, Nobel Biocare) were placed and 14 complete‐arch FDPs immediately loaded (mean follow‐up 16.2 ± 1.7 months, 14–18). One implant failed and was immediately replaced. No other surgical or biological complications occurred, accounting for a cumulative success rate of 98.3%. No prosthetic complication occurred, leading to 100% prosthetic success rate. Mean ISQ at implant placement was 71 ± 2.8 (65–78). The mean MBL was −0.53 ± 0.28 mm (−0.22 to −1.12 mm). Plaque and bleeding scores were 14.4 ± 8.18 and 7.15 ± 4.4, respectively. Conclusion: Within the limitations of this proof‐of‐concept dynamic navigation was effective to deliver in the planned coordinates both implants and prosthesis and guide bone and soft tissue sculpturing. Immediate loading of digitally prefabricated esthetically driven complete‐arch FDP was facilitated, resulting in high implant and prosthetic success rates. Clinical Significance: The investigated digital workflow integrating dynamic navigation may overcome the difficulties related to immediate positioning and loading of digitally prefabricated complete‐arch FDP. The navigation guided soft and bone tissues sculpturing, associated to xenogeneic collagen matrix grafting, represented a predictable technique to achieve the digitally planned interface, reestablishing the mucosal dimension required for the protection of underlying bone while maintaining tissue health. [ABSTRACT FROM AUTHOR]

Purpose: A prospective clinical study to compare for the first time the accuracy of digital and conventional maxillary implant impressions for completely edentulous patients. Materials and Methods: Sixteen patients received maxillary implant supported fixed complete dentures. After the verification of the conventional final casts, the casts were scanned with a desktop (extraoral) scanner. Intraoral full‐arch digital scans were also obtained with scan bodies and STL files. Extraoral and intraoral scans were superimposed and analyzed with reverse engineering software. The primary outcome measure was the assessment of accuracy between scans of the verified conventional casts and digital full‐arch impressions. The secondary outcome was the effect of the implant number on the 3D accuracy of impressions with Spearman's rank correlation coefficient. Results: The 3D deviations between virtual casts from intraoral full‐arch digital scans and digitized final stone casts generated from conventional implant impressions were found to be 162 ± 77 μm. In the 4‐implant group, 5‐implant group, and 6‐implant group the 3D deviations were found to be 139 ± 56 μm, 146 ± 90 μm, and 185 ± 81 μm, respectively. There was a positive correlation between increased implant number and 3D‐deviations, but there was no statistically significant difference (p = 0.191). Conclusions: The 3D accuracy of full‐arch digital implant scans lies within previously reported clinically acceptable threshold. Full‐arch digital scans and a complete digital workflow in the fabrication of maxillary fixed complete dentures may be clinically feasible. [ABSTRACT FROM AUTHOR]

Background: Discordant opinions have emerged among clinicians and researchers regarding a digital impression for full-arch implant-supported fixed dental prostheses (FDPs). The purpose of this study was to assess the fit of screw-retained milled frameworks on six implants realized from digital impressions through the Sheffield test. Methods: One patient received a maxillary full-arch implant-supported FDP. Six months after the surgical procedure, ten intraoral full-arch digital impressions were performed to mill ten frameworks. To clinically assess the fit, the Sheffield test was applied for all frameworks. The gaps among the frameworks and the implant analogs were measured using a microscope on the master model realized with a traditional impression. The Wilcoxon sum-rank test was used to compare the misfit value among the different implant positions. Results: The Sheffield test did not show gaps in the framework–implant interfaces when the screw was completely tightened on the more distal implant for all the milled frameworks. The mean misfit value calculated after microscope examination was 38 ± 5 μm. Differences that were statistically significant emerged when the misfit values of central positions were compared with other values. Conclusions: The use of full-arch implant digital impressions represents a viable alternative to traditional impressions for the fabrication of implant-supported FDPs.

Evaluating the impact of the prosthetic material on implant- and prosthetic survival of implant-supported fixed complete dentures. Electronic and hand searches were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to identify clinical studies including at least 10 patients restored with implant-supported dentures. The primary outcome was to evaluate the implant survival rate according to the applied restorative materials. The prosthetic survival rate was evaluated as secondary outcomes. Forty-one of 2254 studies were finally selected. A statistically significant difference (p = 0.0337) was found between implant survival rates in the main restorative groups (metal-ceramic:97%(95%CI [0.96;0.98]), all-ceramic:99%(95%CI [0.98;1.00]), metal-resin:97%(95%CI [0.96;0.98])). Prosthetic survival rates were: (metal-ceramic:95%(95%CI [0.89;0.97]), all-ceramic:97%(95%CI [0.92;0.99]), metal-resin:97%(95%CI [0.95;0.98]), with no statistically significant difference (p = 0.3796) between the groups. Chipping incidence rates were as follows: metal-ceramic:8%(95%CI[0.03;0.20]), all-ceramic:15%(95%CI [0.06;0.32]), and metal-resin:22%(95%CI [0.13;0.33]). Five types of exact restorative materials were identified (porcelain-fused-to-non-precious alloy, porcelain-fused-to-zirconia, precious-metal-acrylic-resin, non-precious-metal-acrylic resin, and PMMA). Again, implant survival rates were statistically significantly influenced by the applied restorative materials (p = 0.0126), whereas, no significant differences were reported regarding prosthetic survival rate. Prosthetic material selection seems to have no clinically relevant influence on implant- and prosthetic survival rate in implant-supported fixed complete dentures. Due to the high chipping rate, quantifying prosthetic survival alone does not seem to be a reliable tool for evaluating the outcome of the restorations and providing recommendations. These results, along with the obvious lack of evidence, suggest that clinicians must exercise caution whenever porcelain-fused-to-zirconia or metal-resin restorations are considered. [ABSTRACT FROM AUTHOR]

Objective: To assess the clinical outcomes of implant‐supported full‐arch immediate prosthesis over 6 months of functions and analyze the risk factors of prosthetic complications. Materials and Methods: This retrospective cohort study included patients who were treated with implant‐supported full‐arch restoration under immediate loading protocol between April 2008 and June 2016, and who wore the immediate prosthesis for more than 6 months. Medical charts were reviewed for the patients' general information, implant information, prosthetic information, and details of any prosthetic complications. Prosthetic complications were classified as follows: class I, prosthesis loosening; class II, fewer than three artificial teeth fractured; class III, three or more artificial teeth fractured; and class IV, resin base fractures. A cox proportional hazards ratio model was adopted to analyze the potential risk factors for class IV complications. Results: A total of 114 patients (mean age, 56.73 ± 10.19 years) and 144 prostheses were included. The average wearing time for the immediate prosthesis was 21.9 months, and 62 (54.39%) patients experienced prosthetic complications, 30 of whom suffered from complications more than once. The most common complications were class II complications (12.3%) during the first 6 months of functioning and class IV complications (28.1%) during the entire function period. Class II complications were more common in the anterior region, while class IV complications occurred more often in the posterior region. The multivariable Cox proportional hazards regression model showed that a prosthesis in the maxilla (HR = 3.37, P =.001) and fiber reinforcement (HR = 0.39, P = .021) were significantly related to class IV complications. Conclusions: Implant‐supported full‐arch immediate prosthesis functioning over 6 months have a high prevalence of prosthetic complications. Fiber‐reinforcement could reduce the prevalence of class IV complications when acrylic immediate prosthesis functioned longer than 6 months. Avoiding using the anterior teeth of the immediate prosthesis to tear pliable but strong food may prevent tooth fracture. [ABSTRACT FROM AUTHOR]

Objective: To assess the prostheses and implants survival rate and peri‐implantitis rate in edentulous patients treated with full‐arch screw‐retained implant‐supported fixed dental prostheses (FSIFDPs) and full‐arch telescopic‐retained implant‐supported fixed dental prostheses (FTIFDPs) over an observation period of at least 5 years. Materials and methods: From 2004 to 2012, 696 implants were inserted into 78 patients with 102 prostheses. The FSIFDP group comprised 31 patients (37 prostheses, 232 implants), whereas the FTIFDP group comprised 47 patients (65 prostheses, 464 implants). Prosthesis and implant estimated cumulative survival rates (ECSR) and estimated cumulative peri‐implantitis rates (ECPR) were assessed. The follow‐up period was 5–12 years. Kaplan–Meier survival curves with the log‐rank test were used to evaluate outcomes. Results: The 12‐year prosthesis ECSR was 96.8% (95% CI: 79.2–99.5, 36/37 prostheses) in the FSIFDP group and 96.4% (95% CI: 86.3–99.1, 63/65 prostheses) in the FTIFDP group, whereas the 12‐year implant ECSR was 99.5% (95% CI: 96.4–99.9, 231/232 implants) in the FSIFDP group and 98.7% (95% CI: 96.9–99.5, 459/464 implants) in the FTIFDP group. The 12‐year ECPR at the prosthesis level was 12.8% (95% CI: 12.7–47.6, 4/37 prostheses) in the FSIFDP group and 12.8% (95% CI: 11.4–24.1, 6/65 prostheses) in the FTIFDP group. The 12‐year ECPR at the implant level was 4.4% (95% CI: 4.3–23.0, 6/232 implants) in the FSIFDP group and 2.2% (95% CI: 2.0–12.3, 7/464 implants) in the FTIFDP group. Conclusion: FTIFDPs have clinical results comparable to those of FSIFDPs. Therefore, FTIFDPs can be useful. [ABSTRACT FROM AUTHOR]

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Background: The etiology of peri-implantitis is multifactorial, and it is not directly linked to the quantitative amount of plaque. The aim of this study was to evaluate the influence of subgingival microbiota around implants supporting full-arch restorations on clinical indexes of peri-implant health. Method: 47 patients (54 full-arch fixed rehabilitations) were included. Based on the highest value of probing depth (PD), 47 implants (in the test arch), 40 natural teeth and 7 implants (in the antagonist arch) were selected for microbiological sampling (traditional PCR and real-time PCR). Periodontal indexes (plaque index, PlI; probing depth, PD; bleeding on probing, BOP; peri-implant suppuration, PS) and marginal bone loss were also recorded. Results: Despite abundant plaque accumulation, the peri-implant parameters were within normal limits. No statistical difference was found in the microbial population around the test implants and antagonist natural teeth. Treponema denticola was present in a significantly higher amount around implants with increased PlI. Implants with increased BOP showed a significant increase in Treponema denticola and Tannerella forsythia. A significantly higher presence of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia was identified around the implants affected by peri-implantitis and in smokers. Conclusions: Peri-implantitis is characterized by a complex and polymicrobial disease, that might be influenced by the qualitative profile of plaque. Smoking might also favor implant biological complications in full-arch fixed prosthesis.