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Objectives: To systematically analyze the accuracy of robotic surgery for dental implant placement. Materials and Methods: PubMed, Embase, and Cochrane CENTRAL were searched on October 25, 2023. Model studies or clinical studies reporting the accuracy of robotic surgery for dental implant placement among patients with missing or hopeless teeth were included. Risks of bias in clinical studies were assessed. Meta‐analyses were undertaken. Results: Data from 8 clinical studies reporting on 109 patients and 242 implants and 13 preclinical studies were included. Positional accuracy was measured by comparing the implant plan in presurgery CBCT and the actual implant position in postsurgery CBCT. For clinical studies, the pooled (95% confidence interval) platform deviation, apex deviation, and angular deviation were 0.68 (0.57, 0.79) mm, 0.67 (0.58, 0.75) mm, and 1.69 (1.25, 2.12)°, respectively. There was no statistically significant difference between the accuracy of implants placed in partially or fully edentulous patients. For model studies, the pooled platform deviation, apex deviation, and angular deviation were 0.72 (0.58, 0.86) mm, 0.90 (0.74, 1.06) mm, and 1.46 (1.22, 1.70)°, respectively. No adverse event was reported. Conclusion: Within the limitation of the present systematic review, robotic surgery for dental implant placement showed suitable implant positional accuracy and had no reported obvious harm. Both robotic systems and clinical studies on robotic surgery for dental implant placement should be further developed. [ABSTRACT FROM AUTHOR]

Objectives: To introduce a modified guided bone regeneration (GBR) technique using intact periosteum and deproteinized bovine bone mineral (DBBM) for peri‐implant augmentation and compare the clinical outcomes with those of conventional GBR. Materials and Methods: Patients who received peri‐implant augmentation in posterior sites between 2015 and 2021 were reviewed in this study. Group A was treated with a modified GBR technique, and Group B was treated with conventional GBR. For group comparison, propensity score matching was performed with a sensitivity analysis. The implant survival rate, dimensional changes in hard tissue, marginal bone loss (MBL), and peri‐implant parameters were evaluated. Results: In total, 114 implants from 98 patients were included. The implant survival rates were 95.74% in Group A and 95.00% in Group B during the follow‐up period. At 6 months, the median horizontal thickness was recorded at 0.87 mm (IQ1–IQ3 = 0.00–1.75 mm) in Group A, exhibiting a relatively lower value compared to the corresponding measurement of 0.98 mm (IQ1–IQ3 = 0.00–1.89 mm) in Group B (p =.937). Vertical height displayed no statistically significant intergroup difference between the two groups (p =.758). The mean follow‐up period was 25.83 ± 12.93 months after loading in Group A and 27.47 ± 21.29 months in Group B (p =.761). MBL and peri‐implant parameters were comparable between the two groups. Conclusions: Within the limitations of this study, the modified GBR technique using intact periosteum and DBBM grafting might be a viable alternative to correct bone defects around implants in molar and premolar sites. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the esthetic outcome, as well as clinical, radiographic, and volumetric tissue alterations 1 year after immediate implant placement (IIP) with connective tissue grafting (CTG) versus dual‐zone concept (DZ) at sites with thin labial bone in the esthetic zone. Materials and Methods: This randomized clinical trial included 30 patients treated with IIP simultaneous with either CTG or DZ (n = 15 each). Pink esthetic score (PES) was assessed 6 months after crown placement as the primary outcome. Amount of bone labial to the implant, labio‐palatal ridge reduction, and crestal bone changes were measured via CBCT after 1 year. Volumetric analysis of linear labial soft tissue contour, interdental, and mid‐facial soft tissue level changes, and total volume loss (mm3) were measured after 1 year. Results: Similar PES was observed in the CTG (12.53 ± 1.13) and DZ (12.13 ± 1.55) groups, with no significant difference (p = 0.42). Likewise, there were no statistically significant differences found between the two groups in labio‐palatal bone reduction (mm&%), interdental papillae, and mid‐facial gingival levels (p > 0.05). However, the mean vertical crestal bone changes in the CTG and DZ groups were −1.1 ± 0.6 mm and 0.2 ± 1.0 mm, respectively, with a statistically significant difference (p = 0.0002). Moreover, CTG revealed less linear and total volume (mm3) loss in the labial soft tissue which was statistically significant compared to DZ (p = 0.007). Conclusion: Both groups demonstrated the same PES, nevertheless, volumetric analysis revealed twice total labial volume loss in DZ compared to CTG. It might be concluded that the use of CTG with IIP caused less horizontal reduction in the supra‐implant complex compared to the DZ. [ABSTRACT FROM AUTHOR]

Objective: To assess the radiological and histological outcome after horizontal guided bone regeneration (GBR) with deproteinized bovine bone mineral (DBBM) alone or in combination with particulate autogenous bone (PAB). Materials and Methods: Eighteen edentulous patients with an alveolar ridge of ≤4 mm were included in this split‐mouth randomized controlled trial. Horizontal GBR with a graft composition of 100% DBBM (100:0) on one side and 90% DBBM and 10% PAB (90:10) on the other side were conducted in all patients. Cone beam computed tomography (CBCT) was obtained preoperatively, immediately postoperative, and after 10 months of healing. Width and volumetric changes in the alveolar process were measured on CBCT. Implants were placed after 10 months of graft healing where biopsies were obtained for histomorphometrical evaluation. Results: The gained widths were 4.9 (±2.4) mm (100:0) and 4.5 (±2.0) mm (90:10) at 3 mm from the top of the crest, and 5.6 (±1.3) mm (100:0) and 4.6 (±2.1) mm (90:10) at 6 mm from the top of the crest. The mean volumetric reductions were 32.8% (±23.8) (100:0) and 38.2% (±23.2) (90:10). Histomorphometry revealed that mean percentages of bone were 50.8% (±10.7) (100:0) and 46.4% (±11.3) (90:10), DBBM were 31.6% (±12.6) (100:0) and 35.4% (±14.8) (90:10), and non‐mineralized tissue were 17.6% (±11.7; 100:0) and 18.2% (±18.2) (90:10). No significant differences were evident between in any evaluated parameters. Conclusions: There were no additional effects of adding PAB to DBBM regarding bone formation, width changes, or volumetric changes after 10 months of graft healing. [ABSTRACT FROM AUTHOR]

Objective: Optimal implant planning and placement allows the prosthesis to be well designed to achieve a satisfactory aesthetic and functional outcome. We aimed to compare deviations between implant planning and placement with the assistance of dynamic computer‐assisted implant surgery (d‐CAIS) or autonomous robotic computer‐assisted implant surgery (r‐CAIS) methods in a clinical setting. Methods: The retrospective analysis of medical records between 2021 July and 2022 December was conducted to compare the implantation accuracy of the d‐CAIS and r‐CAIS system in partially edentulous patients through cone‐beam computed tomography. Patient‐reported outcomes (PROs) were recorded using a visual analogue scale (VAS). The Kolmogorov–Smirnov test was used to check the data distribution. Student's t‐test or Mann–Whitney U‐test was used as appropriate, with a defined significant difference (p <.05). Results: Seventy‐seven patients were analysed (124 implants), with 38 patients (62 implants) in the d‐CAIS group and 39 patients (62 implants) in the r‐CAIS group. The differences between d‐CAIS and r‐CAIS were 4.09 ± 1.79° versus 1.37 ± 0.92° (p <.001) in angular deviation; 1.25 ± 0.54 versus 0.68 ± 0.36 mm (p <.001) in coronal global deviation; 1.39 ± 0.52 versus 0.69 ± 0.36 mm (p <.001) in apical global deviation; the results of the PROMs showed no statistical difference between the two groups. Conclusions: r‐CAIS allows more accurate implant placement than the d‐CAIS technology. And both groups achieved overall satisfactory outcomes via VAS (Chinese Clinical Trial Registry ChiCTR2300072004). [ABSTRACT FROM AUTHOR]

Aim: To compare measurements on images obtained by magnetic resonance imaging (MRI) and cone beam CT (CBCT) for height, width, and area in alveolar bone sites in human jaw specimens. Material and Methods: Forty edentulous alveolar posterior sites in human cadaver specimens were imaged using CBCT scanners, and with zero‐echo‐time MRI (ZTE‐MRI). Semi‐automatic volume registration was performed to generate representative coronal sections of the sites related to implant planning. ZTE‐MRI sections were also presented after grayscale inversion (INV MRI). Three observers measured bone height, bone width 5 mm from the alveolar crest, and bone area stretching from the width measurement to the top of the alveolar crest in the images. Interobserver agreement was assessed by intra‐class correlation coefficients (ICC). The measurements were analyzed using two‐way repeated measures ANOVA factoring observer and image type. Results: ICC was >0.95 for bone height, width, and bone area. No significant differences among observers (p = 0.14) or image type (p = 0.60) were found for bone height. For bone width, observer (p = 0.14) was not a significant factor, while ZTE‐MRI produced width estimates that were significantly different and systematically smaller than CBCT‐based estimates (p ≤ 0.001). Observer (p = 0.06) was not a significant factor regarding the bone area measurements, contrary to the imaging type where ZTE‐MRI led to significantly smaller area estimates than CBCT (p ≤ 0.001). Conclusion: Bone height measurements were essentially equivalent using CBCT and MRI. This was found regardless of grayscale choice for the MRI. However, ZTE‐MRI resulted in smaller estimates of bone width and area. [ABSTRACT FROM AUTHOR]

Objectives: To assess in a prospective randomized trial two phycogenic bone substitutes—biphasic calcium phosphate (BCP) versus almost pure hydroxyapatite (HA)—for their volume stability and clinical implications after sinus floor elevation (SFE). Materials and Methods: Twenty patients requiring lateral‐window SFE 6 months prior to implant surgery were randomized to a BCP or HA group. As primary outcome, the grafts were analyzed for volume stability, using four cone‐beam computed tomography scans obtained immediately/6/12/24 months after SFE. Secondary outcomes were implant survivval, success, periotest values, oral‐health‐related quality of life (OHIP‐G14), and pain (VAS). Results: Kolmogorov–Smirnov goodness‐of‐fit test revealed normal distribution of samples (p =.200). At 6/12/24 months, the augmented volumes decreased to 96/92/90% (HA) or 99/96/96% (BCP). Volume changes were significantly a factor of time (p <.001; generalized linear model with repeated measures) and reached significantly lower values in HA group (p =.018). Significant intergroup difference in volume losses was notable at 24 months (p =.021; t‐test for independent samples). Periotest values decreased from −3/−4.1 (HA/BCP) after implant placement to −6.3/−4.5 (HA/BCP) after 6 months. OHIP scores diverged at 2 months (HA: 9.5; BCP: 5.2) and largely resolved by 24 months (HA: 1.3; BCP: 1.9). VAS scores were comparable, 2.2 at 1 week after SFE being their highest mean level. Conclusions: After 2 years, both groups experienced no biological or technical complications, demonstrating a consistent healing trajectory without notable symptoms. Although no significant differences were observed in implant stability and survival, BCP demonstrated higher volume stability than HA. [ABSTRACT FROM AUTHOR]

Objectives: To compare implant placement accuracy and patient‐centered results between the dynamic computer‐assisted implant surgeries (d‐CAISs) using marker‐based and marker‐free registration methods. Materials and Methods: A double‐armed, single‐blinded randomized controlled trial was conducted, in which 34 patients requiring single implant placement at the esthetic zone were randomly assigned to the marker‐based (n = 17) or marker‐free (n = 17) groups. The marker‐based registration was performed using a splint containing radiopaque markers, while the marker‐free registration used natural teeth. The primary outcome assessed implant positioning accuracy via angular and linear deviations between preoperative and postoperative implant positions in CBCT. Patients were also surveyed about the intraoperative experience and oral health impact profile (OHIP). Results: The global linear deviations at the implant platform (0.82 ± 0.28 and 0.85 ± 0.41 mm) and apex (1.28 ± 0.34 and 0.85 (IQR: 0.64–1.50) mm) for the marker‐based and marker‐free groups respectively showed no significant difference. However, the angular deviation of the marker‐free group (2.77 ± 0.92°) was significantly lower than the marker‐based group (4.28 ± 1.58°). There was no significant difference in the mean postoperative OHIP scores between the two groups (p =.758), with scores of 2.74 ± 1.21 for marker‐based and 2.93 ± 2.18 for marker‐free groups, indicating mild oral health‐related impairment in both. Notably, patients in the marker‐free group showed significantly higher satisfaction (p =.031) with the treatment procedures. Conclusions: D‐CAIS with a marker‐free registration method for single implantation in the anterior maxilla has advantages in improving implant placement accuracy and patients' satisfaction, without generating a significant increase in clinical time and expenses. [ABSTRACT FROM AUTHOR]

Introduction: The radiographic examination of alveolar bone using 3D radiographic examination is essential in dental implant treatment planning. Our study aimed to systematically review and quantitatively analyze the correlation between alveolar bone parameters, specifically bone density and cortical bone thickness, assessed using cone beam computed tomography (CBCT) and/or multidetector computed tomography (MDCT); and primary implant stability (PIS) determined using implant stability quotient (ISQ), Periotest® value (PTV), and insertion torque value (ITV). Methods: This review was registered in the PROSPERO database (registration number CRD42022307245). An electronic literature search was conducted on the PubMed, SCOPUS, and Web of Science databases for papers published until February 2022. The Quality Assessment in Prognostic Studies (QUIPS) tool was used to assess risk of bias. Meta‐analyses were conducted to calculate the estimated average correlation coefficient based on a multilevel random‐effects model, followed by subgroup analysis. Results: Twenty‐six studies were included in this review, consisting of 17 prospective cohort studies, eight retrospective cohort studies, and one nonrandomized controlled trial. A total of 3109 implants placed in 1171 subjects were analyzed. Twenty‐three studies were evaluated using meta‐analysis. The alveolar bone condition was significantly correlated with ISQ (r = 0.60; p <.001), IT (r = 0.52; p <.001), and PTV (r = −0.42; p <.05). Conclusion: Alveolar bone condition is significantly associated with PIS. Low bone density and thin cortical bone can lead to low PIS; therefore, modification of treatment planning and surgical procedures might be needed to avoid poor osseointegration. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the possible interference of image artifacts (IA) generated by dental implants in the evaluation of furcation involvement (FI) in molars. Methods: Tomographic scans of first molars (1M) were performed in dry skulls in the absence and presence of titanium (TI) and zirconia (ZI) dental implants. FI grades were simulated in the alveoli of the 1Ms. Diagnostic accuracy of FI and level of difficulty were verified. Chi‐squared test and logistic regression analysis were used. Results: There was no difference in the diagnostic accuracy of FI between the arches (p =.117). The highest diagnostic accuracy value for the implant variable was found in the absence of implants (88.3%) and the lowest in the presence of two ZI implants (66.7%). The highest diagnostic accuracy value for FI was observed in grade 0 (G0). There was no significant difference between the arches regarding the evaluators' perception of difficulty (p >.05). Assessments were considered difficult in 12.7% of the TI implants and in 29% of the ZI implants. Regarding the number of dental implants, assessments were considered difficult in 24.4% cases including one implant and 17.4% cases including two implants. The logistic regression model showed a significant p‐value only for one and two ZI implants (p =.0061 and p =.0096, respectively). Conclusion: The presence of dental implants in the region adjacent to the area of investigation of FI decreased the diagnostic accuracy while increasing the perception of difficulty by the examiners, especially in cases with ZI implants. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the accuracy of dental implant placement using the robotic computer‐assisted implant surgery (r‐CAIS) technology in fully edentulous patients. Materials and Methods: Fully edentulous and terminal dentition patients were enrolled for r‐CAIS technology. Based on the cone‐beam computed tomography (CBCT) examination, a customized positioning marker and a preoperative surgical plan were created before surgery. During the implant surgery, the implant osteotomy and placement were automatically performed using an autonomous robotic surgery system under the surgeon's supervision. A postoperative CBCT scan was used to determine the discrepancies between the planned and placed implants. Results: Ten patients with 59 implants underwent autonomous robotic surgery. No adverse surgical events occurred. The deviations of global coronal, global apical, and angular were 0.67 ± 0.37 mm (95% CI: 0.58–0.77 mm), 0.69 ± 0.37 mm (95% CI: 0.59–0.78 mm), and 1.27° ± 0.59° (95% CI: 1.42°–1.11°), respectively. Conclusions: The autonomous r‐CAIS technology proved an accurate surgical approach for implant placement in fully edentulous patients due to the control of the angular deviation. Autonomous robotic surgery seems promising as an accurate technology for treating fully edentulous patients. However, further trials are required to provide more hard clinical evidence. [ABSTRACT FROM AUTHOR]

Objectives: To radiographically evaluate the stability of the bone substitute augmented outside the buccal bony arch contour in the maxillary esthetic zone. Materials and Methods: Patients who missed a single anterior tooth and received simultaneous GBR in implant surgery were included. The contralateral homonymous area of the implant site was horizontally mirrored as the individual bone arch contour. According to the relative position of the postoperative buccal grafts and bone arch contour at the implant shoulder, 62 patients were allocated into the outside‐contour (OC) and inside‐contour (IC) groups. Cone‐beam computed tomography was performed before surgery, after implant insertion, before re‐entry surgery, and at follow‐up. The profilometric changes of the buccal bone plate were analyzed via the bone distance to the mirrored bony contour. Results: At the implant shoulder, the bone distance in the OC group was higher than that in the IC group, with statistically significant differences at re‐entry surgery and follow‐up. However, the bone grafts outside the bone arch contour were reduced into the contour after remodeling and showed more bone resorption than the IC group. At other vertical levels below the implant shoulder, bony grafting of overcontour 1–2 mm range was favorable to regenerate stable bone plates reaching the individual contour at follow‐up. Conclusions: The overaugmented bone outside the buccal bone arch contour tended to remodel into the original contour, which indicates that the anterior bone arch contour is worthy of careful observation for deciding buccolingual implant position and bone augmentation width. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study, which included a 5‐year follow‐up, was to compare peri‐implant soft tissue health, crestal bone loss (CBL), and buccal bone thickness (BBT) around triangular cross‐section neck (TN) or round neck (RN) implants, using cone‐beam computed tomography. Materials and Methods: This study was initially designed as a prospective 1‐year randomized controlled study and then extended with a 5‐year retrospective evaluation of clinical and radiographic records. In the initial 1‐year study, a total of 20edentulous patients receiving 40 implants with similar diameters were randomly assigned to the RN or TN groups using a split‐mouth design. Pocket probing depths (PPD), plaque index (PI), and gingival index (GI) were recorded at postoperative month 12. CBL and BBT at three levels (0, −2, and −4 mm) were evaluated 1 year after insertion. Five years after insertion, PPD, PI, GI, CBL, and BBT were recorded as patients were recalled for clinical and radiographic monitoring. Results: Nineteen patients completed the study. After 5 years, no significant differences in PPD, PI, and GI scores and BBT values between the two groups (p >.05). The mean ± SD CBL values at the final follow‐up visit were −0.71 ± 0.69 mm for TN and −1.03 ± 0.86 mm for RN (p <.01). Conclusions: These results suggest better crestal bone preservation using implants with TN when compared to RN after a 5‐year follow‐up. However, TN showed similar results to RN regarding peri‐implant soft tissue health and BBT. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the accuracy of implant placement using a dynamic navigation system in fully edentulous jaws and to analyze the influence of implant distribution on implant position accuracy. Materials and Methods: Edentulous patients who received implant placement using a dynamic navigation system were included. Four to six mini screws were placed in the edentulous jaw under local anesthesia as fiducial markers. Then patients received CBCT scans. Virtual implant positions were designed in the planning software based on CBCT data. Under local anesthesia, implants were inserted under the guidance of the dynamic navigation system. CBCTs were taken following implant placement. The deviation between the actual and planned implant positions was measured by comparing the pre‐ and postsurgery CBCT. Results: A total of 13 edentulous patients with 13 edentulous maxillae and 7 edentulous mandibles were included, and 108 implants were placed. The average linear deviations at the implant entry point and apex were 1.08 ± 0.52 mm and 1.15 ± 0.60 mm, respectively. The average angular deviation was 2.85 ± 1.20°. No significant difference was detected in linear and angular deviations between the maxillary and mandibular implants, neither between the anterior and posterior implants. Conclusions: The dynamic navigation system provides high accuracy for implant placement in fully edentulous jaws, while the distribution of the implants showed little impact on implant position accuracy. [ABSTRACT FROM AUTHOR]

Objectives: To determine the effect of restoration artifact ('metal artifact') on registration accuracy of an intraoral scan and cone‐beam computed tomography (CBCT) scan, comparing fiducial marker‐based registration with markerless registration. Materials and methods: A maxillary model was fitted with multiple configurations of zirconia crowns to simulate various states of oral rehabilitation. Intraoral scans and CBCT scans (half and full rotation) were acquired. Registration was performed using markerless (point‐based registration with surface‐based refinement) and fiducial marker‐based registration. Each experimental condition was repeated 10 times (n = 320). The absolute deviation was measured at the canines and first molars, and the average and maximum values were analysed using multiple linear regression. Results: R2 was 0.874 for average error and 0.858 for maximum error. For markerless registration, there were 0.041 mm (p <.001) and 0.045 mm (p <.001) increases in average and maximum error per crown, respectively. For fiducial marker‐based registration, the effect of additional crowns was not statistically significant for average (p =.067) or maximum (p =.438) error. For a full arch of crowns, the regression model predicted average and maximum errors of 0.581 and 0.697 mm for the markerless technique, and 0.185 and 0.210 mm for the fiducial marker‐based technique. Overall, the fiducial marker‐based technique was more accurate for four or more crowns. The half rotation scan increased average error by 0.021 mm (p =.001) and maximum error by 0.029 mm (p <.001). Conclusions: Under the present study's experimental conditions, the fiducial marker‐based technique should be considered if four or more full‐coverage highly radiopaque restorations are present. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to retrospectively evaluate the long‐term clinical outcomes of lateral sinus floor elevation (LSFE) in patients with sinus floor defects. Materials and Methods: Between 2008 and 2020, patients with sinus floor defects were recruited after confirmation on preoperative cone‐beam computed tomography (CBCT). The split‐thickness flap technique with a palatal crestal incision was used to manage tissue adhesion in the bone defects area. A resorbable collagen membrane was used to close the sinus floor defects from the crestal side before bone substitute placement. Of 58 implants, 47 (81.0%) were placed after an 8‐month healing period, whereas 11 were placed simultaneously. Patients were followed up by radiography and clinical examination for 1–9 years. Finally, the cumulative survival rate (CSR) of implants, surgical complications, and marginal bone loss (MBL) were recorded and analyzed. Results: In total, LSFE was performed in 36 sinuses (35 patients) with sinus floor defects, of which surgery was completed in 35 sinuses (97.2%) in the first attempt. Schneiderian membrane perforations (SMP) occurred in 10/36 (27.8%) sinuses; nine were repaired carefully, whereas one surgery was suspended due to complicated SMP, and successful re‐entry LSFE was performed 4 months later. After a follow‐up period of 1–9 years, the CSR was 96.5% at the 1‐year, 3‐year, 5‐year, and 7‐year follow‐ups and 64.3% at the 8‐year follow‐up. Conclusion: Within the limitations of this study, sinus floor defects seem not to compromise LSFE therapy after appropriate management and long‐term clinical outcomes are predictable. [ABSTRACT FROM AUTHOR]

This document provides summaries of various research studies related to dental implants and bone regeneration. The studies cover a range of topics, including surgical guides, mylohyoid line width, electrolytic cleaning, microbial and cytokine changes, extra-short implants, autologous dentin graft, antidepressant medication, and biomechanical analysis. The studies offer valuable insights for clinicians and researchers in the field. One study found that both cemented and screw-retained crowns had similar clinical outcomes, but screw-retained crowns had a higher incidence of technical complications. Clinicians should consider these potential complications when choosing a method for single implant restorations in the maxilla. Overall, the studies demonstrate positive outcomes and provide valuable insights into dental implant procedures. [Extracted from the article]

Aim: To compare, at different levels from the alveolar crest, the radiographic outcomes of equine‐derived collagenated xenogeneic bone blocks (CXBB) and autogenous bone blocks (ABB) used for lateral alveolar ridge augmentation. Materials and Methods: Sixty‐four patients with tooth gaps in atrophic alveolar ridges with ≤4 mm were randomly assigned to lateral augmentation using CXBB or ABB. The lateral bone thickness (LBT) was measured 2, 4, 6, 8, and 10 mm below the alveolar crest using CBCT scans obtained before augmentation surgery and at 30 weeks, prior to implant placement. Statistical analysis was performed using Shapiro–Wilk, Fisher's exact, Mann–Whitney, and Wilcoxon signed‐rank tests. Results: Both CXBB and ABB resulted in significant total and buccal LBT gains at 2, 4, 6, 8, and 10 mm. LBT gains were similar between CXBB‐ and ABB‐augmented sites, except for greater buccal LBT gains at 8 mm at CXBB‐augmented sites. While ABB‐augmented sites gained vertical bone height, CXBB‐treated sites suffered vertical bone loss (CXBB: −0.16 mm; ABB: 0.38 mm, p <.0009). Conclusions: CXBB and ABB were both associated with significant and similar LBT gains at 30 weeks. [ABSTRACT FROM AUTHOR]

Objective: The aims of this clinical trial were to evaluate the radiographic dimensional changes in alveolar ridge and patient‐reported outcomes following tooth extraction and alveolar ridge preservation (ARP) using either deproteinized bovine bone mineral (DBBM) with EMD or DBBM alone. Methods: Participants requiring at least one posterior tooth extraction and ARP were randomly allocated into two treatment groups: ARP using either DBBM with EMD or DBBM alone. Cone‐beam computed tomography (CBCT) images were recorded immediately prior to extraction and at 6 months. Changes in alveolar ridge height (ARH) and alveolar ridge width (ARW) at 1, 3, and 5 mm were recorded. Results: A total of 18 participants with 25 preserved sites were evaluated. ARH and ARW changed significantly from baseline to 6 months for both treatment groups but the difference between the groups was not statistically significant over the 6‐month follow‐up period (ARH: DBBM/EMD 1.26 ± 1.53 mm vs. DBBM 2.26 ± 1.60 mm; ARW‐1 DBBM/EMD 1.98 ± 1.80 mm vs. DBBM 2.34 ± 1.89 mm). A significant difference, favoring DBBM with EMD group, was observed in percentage of sites that had less than 1 mm loss in ARH (54.5% sites in DBBM/EMD group vs. 14.3% sites in DBBM alone group). The participants' perception of bruising, bleeding, and pain in the first two postoperative days was significantly in favor of DBBM alone group. Conclusions: There were no significant differences in radiographic mean measurements of ARH and ARW following ARB with DBBM and EMD or DBBM alone. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the influence of metal artefact reduction (MAR) in the diagnosis of dental implant contact with the mandibular canal (MC) using cone beam computed tomography (CBCT). Methods: Dental implants were installed with surgical guides in the posterior hemiarches of 10 dry human mandibles: 0.5 mm above to the MC cortex (G1/n = 8) and 0.5 mm inside the MC (G2/n = 10). The experimental set‐up was scanned with two CBCT equipment using 85 kV and 90 kV, MAR ON or OFF, and different tube currents (4 mA, 8 mA and 10 mA). Two dentomaxillofacial radiologists (DMFRs) and two dentists (DDS) scored the relation between the dental implant and MC. Descriptive statistics were used to observe the absolute frequency of scores. Sensitivity, specificity and accuracy were calculated considering the known relation between the dental implant and the MC interior. McNemar's test (α =.05) was applied to compare the diagnostic efficacy of MAR ON versus MAR OFF. Results: Overall specificity was higher than sensitivity for both DDS and DMFR (97% vs. 50% and 92.0% vs. 78.0% respectively). There was a significant effect of MAR (p =.031) for DMFR in the case of contact between the dental implant with the MC interior, in which sensitivity decreased with MAR activation from 90% to 40%. DMFR observers showed a better diagnostic performance compared with the DDS observers (accuracy of 84.0% and 71.0%, respectively). Conclusions: Due to the limited efficacy of MAR, it should not be used when conducting CBCT scans for the evaluation of contact between the implant and the mandibular canal. [ABSTRACT FROM AUTHOR]

Aim: To assess in vitro the workflow for alveolar ridge augmentation with customised 3D printed block grafts and simultaneous computer‐assisted implant planning and placement. Methods: Twenty resin mandible models with an edentulous area and horizontal ridge defect in the region 34–36 were scanned with cone beam computed tomography (CBCT). A block graft for horizontal ridge augmentation in the region 34–36 and an implant in the position 35 were digitally planned. Twenty block grafts were 3D printed out of resin and one template for guided implant placement were stereolithographically produced. The resin block grafts were positioned onto the ridge defects and stabilised with two fixation screws each. Subsequently, one implant was inserted in the position 35 through the corresponding template for guided implant placement. Optical scans of the study models together with the fixated block graft were performed prior to and after implant placement. The scans taken after block grafting were superimposed with the virtual block grafting plan through a best‐fit algorithm, and the linear deviation between the planned and the achieved block positions was calculated. The precision of the block fixation was obtained by superimposing the 20 scans taken after grafting and calculating the deviation between the corresponding resin blocks. The superimposition between the scans taken after and prior to implant placement was performed to measure a possible displacement in the block position induced by guided implant placement. The (98–2%)/2 percentile value was determined as a parameter for surface deviation. Results: The mean deviation in the position of the block graft compared to the virtual plan amounted to 0.79 ± 0.13 mm. The mean deviation between the positions of the 20 block grafts measured 0.47 ± 0.2 mm, indicating a clinically acceptable precision. Guided implant placement induced a mean shift of 0.16 ± 0.06 mm in the position of the block graft. Conclusions: Within the limitations of this in vitro study, it can be concluded that customised block grafts fabricated through CBCT, computer‐assisted design and 3D printing allow alveolar ridge augmentation with clinically acceptable predictability and reproducibility. Computer‐assisted implant planning and placement can be performed simultaneously with computer‐assisted block grafting leading to clinically non‐relevant dislocation of block grafts. [ABSTRACT FROM AUTHOR]

Objectives: To develop and assess the performance of a novel artificial intelligence (AI)‐driven convolutional neural network (CNN)‐based tool for automated three‐dimensional (3D) maxillary alveolar bone segmentation on cone‐beam computed tomography (CBCT) images. Materials and Methods: A total of 141 CBCT scans were collected for performing training (n = 99), validation (n = 12), and testing (n = 30) of the CNN model for automated segmentation of the maxillary alveolar bone and its crestal contour. Following automated segmentation, the 3D models with under‐ or overestimated segmentations were refined by an expert for generating a refined‐AI (R‐AI) segmentation. The overall performance of CNN model was assessed. Also, 30% of the testing sample was randomly selected and manually segmented to compare the accuracy of AI and manual segmentation. Additionally, the time required to generate a 3D model was recorded in seconds (s). Results: The accuracy metrics of automated segmentation showed an excellent range of values for all accuracy metrics. However, the manual method (95% HD: 0.20 ± 0.05 mm; IoU: 95% ± 3.0; DSC: 97% ± 2.0) showed slightly better performance than the AI segmentation (95% HD: 0.27 ± 0.03 mm; IoU: 92% ± 1.0; DSC: 96% ± 1.0). There was a statistically significant difference of the time‐consumed among the segmentation methods (p <.001). The AI‐driven segmentation (51.5 ± 10.9 s) was 116 times faster than the manual segmentation (5973.3 ± 623.6 s). The R‐AI method showed intermediate time‐consumed (1666.7 ± 588.5 s). Conclusion: Although the manual segmentation showed slightly better performance, the novel CNN‐based tool also provided a highly accurate segmentation of the maxillary alveolar bone and its crestal contour consuming 116 times less than the manual approach. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to evaluate the effect of aging on the changes in implant stability over time following implant placement. Materials and methods: A total of 104 patients in four age ranges (group 1: <60 years, group 2: 61–70 years, group 3: 71–80 years, and group 4: >80 years) were included. Bone‐level tapered implants were placed without implementing any bone augmentation procedure. The final torque value displayed on the implant engine during implant insertion was recorded. Cone‐beam computed tomography (CBCT) was performed immediately after surgery to analyze the bone quality around the implant. Implant stability was measured immediately after surgery and 2, 4, and 8 weeks after surgery. Results: In the CBCT image, higher grayscale values were observed in the order of group 1, group 2, and groups 3/4, with statistical significance (p <.05). There was no significant difference in the insertion torque values between age groups (p ≥.05). Groups 1 and 2 showed lower implant stability values after 2 and 4 weeks compared to immediately and 8 weeks after surgery (p <.05); however, groups 3 and 4 showed no significant difference between the results measured at different timepoints (p ≥.05). Conclusions: Implant treatment in elderly patients is successful showing a settled implant stability over time following implant placement when the implant is appropriately engaged in the alveolar bone in the absence of bone augmentation. [ABSTRACT FROM AUTHOR]

Objective: To present the results of guided bone regeneration (GBR) with three‐dimensional printing individualized titanium mesh (3D‐PITM) applied to alveolar bone defects with different Terheyden classifications and the factors affecting the osteogenic outcome. Materials and Methods: Fifty‐nine patients, presenting with 61 defect sites, were enrolled between 2018 and 2021. GBR+3D‐PITM was obtained with simultaneous or second stage implant placement. The complication rate, the success rate of the bone grafting procedure and the survival rate of the implant were documented. Bone gain, thickness of pseudo‐periosteum and peri‐implant marginal bone loss (MBL) were measured through digital methods by imaging data (CBCT and X‐ray). Results: Out of 61 sites, 20 were exposed (exposure rate: 32.8%). The width, height, and volume bone gain at P3 (mesh removal) were 5.22 ± 3.19 mm, 5.01 ± 2.83 mm, and 588.91 ± 361.23 mm3, respectively. From P2 (3D‐PITM+GBR) to P3, changes in bone gain were not statistically different in the different Terheyden classifications, the occurrence of exposure (p <.001 for all dimensions) and the different type of pseudo‐periosteum (p =.030 for width and p =.002 for height) were significantly correlated with the reduction of bone gain. Terheyden classification of the defect sites was significantly associated with the occurrence of exposure (p =.014) and types of the pseudo‐periosteum (p =.015). Conclusion: The 3D‐PITM can be used in alveolar bone defects with different Terheyden classification, but cases with severe vertical bone defects have a greater chance of the 3D‐PITM exposure and the exposure can affect the outcome of bone augmentation. [ABSTRACT FROM AUTHOR]

Objective: The present study was conducted to evaluate the effect of soft tissue augmentation using a self‐inflating soft tissue expander when performed before horizontal alveolar ridge augmentation on the outcomes of the bone augmentation procedure. The primary outcome is the bucco‐palatal radiographical changes in alveolar ridge width, while the secondary outcome is the quality of the augmented bone assessed histomorphometrically. Materials and Methods: Sixteen patients underwent horizontal alveolar ridge augmentation using autogenous bone. For the test group, soft tissue expanders were used in a separate surgery before bone grafting surgery. For the control group, patients received treatment including single surgery of bone grafting associated with periosteal releasing incision. Implants were placed in both groups 6 months after bone augmentation. Bucco‐palatal changes in alveolar ridge width were evaluated via cone‐beam computed tomography. Augmented bone quality was assessed histomorphometrically. Results: After 6 months, regarding radiographic bone width, there was no statistically significant difference between the two groups, as mean bone width in group I and group II were 8.57 mm and 8.75 mm, respectively. Regarding histomorphometric analysis, Group I showed significantly higher mean bone surface area fraction, higher median mature collagen area fraction, and higher median blood vessel count than Group II (p‐value =.012), (p‐value =.004), and (p‐value =.014), respectively. Conclusion: Within the limitations of the present study, soft tissue expander has no influence on bone width gain after horizontal alveolar ridge augmentation with an autogenous bone block but may have a positive effect on the quality of augmented bone. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the associations between the cortical bone‐to‐implant contact (CBIC), bone microstructure derived from cone‐beam computed tomography (CBCT), and the primary stability of the implant. Materials and Methods: Twenty‐two patients with 65 implants were enrolled in this study. The peak insertion torque values (ITVs) were measured during implant insertion, and the implant stability quotient (ISQ) values were measured immediately after implant placement and 3 months after surgery. The profiles of the peri‐implant bone structure were outlined using the volumetric reconstruction of the CBCTs and superimposition of the virtual models, and the features of CBIC and bone microstructure parameters were measured. The linear mixed effects model and generalized estimating equation were used to explore the predictors for implant primary stability. Results: The average ITV, baseline, and secondary ISQ values were 31.44 ± 6.54 N·cm, 73.34 ± 7.39, and 80.32 ± 4.58, respectively. Statistically significant correlations were found between ITV and surface area of CBIC (r =.340, p =.006), bone volume fraction (r =.294, p =.017), and bone surface fraction (r = −.278, p =.039). Implants with buccolingual CBIC had a higher ITV than implants without CBIC (p =.016). None of the parameters were associated with baseline and secondary ISQ values in generalized estimating equation analysis (all p >.05). Conclusions: Within the limitations of the study, preoperative CBCT measurements might enable the prediction of ITV and therefore of implant primary stability values. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the accuracy of a miniaturized dynamic navigation system with intraoral markers and two different workflows for dental implantation and to compare with static computer‐assisted implant surgery (sCAIS) surgery. Materials and Methods: Two operators performed a total of 270 implant insertions in polyurethane mandibular models under simulated clinical conditions. Implants were placed after CBCT‐based virtual planning in three different groups: two workflows utilizing dynamic computer‐assisted implant surgery (dCAIS; DG1: marker in CBCT; DG2: 3D‐printed marker) and the others with sCAIS (TG: template guided). Postoperative surface scans were matched to the planning data and allowed an evaluation of the angular and spatial deviation between the planned and the actually achieved implant position. Descriptive statistics were followed by a Mixed Model Analysis to determine the influence of the operator, the method, and operating area on different accuracy parameters and the random effect of the model number. Results: The mean angular deviation ranged from 2.26° (DG1) to 2.96° (TG). The mean 3D deviation at the implant's tip ranged from 1.08 mm (TG) to 1.51 mm (DG2) and at the implant's base from 0.69 mm (TG) to 1.49 mm (DG2). The operator showed no significant influence on the accuracy. The method showed significant influence on singular parameters and the operating area on all spatial accuracy parameters. Conclusions: Dynamic navigation systems with intraoral markers enable accurate implant positioning, which is comparable to the static‐guided implant surgery. 3D‐printed markers provide less accurate results compared to prefabricated markers, attached before CBCT scan. [ABSTRACT FROM AUTHOR]

Objectives: The objective of the study was to evaluate the radiographic changes in sinus mucosal thickness (SMT) in patients with mucosal thickening of odontogenic origin after maxillary molar extraction and lateral sinus augmentation with simultaneous surgical drainage and implant placement. Materials and Methods: Forty‐six patients were included in this study. The changes in SMT were evaluated using cone‐beam computed tomography images produced at four time points: before extraction (T0), before surgery (T1), immediately after surgery (T2), and after prosthesis delivery (T3), and statistical differences between time points were analyzed. The changes in SMT and augmented bone height (ABH) regarding the reason of extraction, smoking, ostial patency, and the presence of postoperative sinusitis were also evaluated. Results: Over time points, SMT gradually decreased (T0: 19.44 ± 9.22 mm, T1: 15.10 ± 8.89 mm, T2: 8.42 ± 6.01 mm, and T3: 4.16 ± 4.91 mm) (p <.05). Five out of 6 patients with ostial obstruction at T1 presented ostial patency at T3. Two patients developed postoperative sinusitis but recovered with medication. Ostial patency at T1, SMT at T1, and reason of extraction did not statistically significantly influence SMT at T3. SMT at T1 had no statistically significant impact on ABH change between T2 and T3. Conclusion: Sinus mucosal thickness was gradually reduced by extraction of compromised teeth and drainage during lateral sinus augmentation. The drainage contributed more to the reduction in SMT. [ABSTRACT FROM AUTHOR]

Objectives: Registration of intra‐oral surface scans to cone beam computer tomography (CBCT) is critical in the digital workflow for static computer‐aided implant surgery (sCAIS). This study aimed to assess the impact of CBCT field of view (FoV) on the precision of digital intra‐oral scan registration. Materials and Methods: Cone beam computer tomography data and intra‐oral scans from 20 patients were included. Small FoV CBCT's were created by digitally segmenting a large FoV into three sextants. Virtual implant planning was performed. Digital intra‐oral scans were repeatedly registered onto their corresponding large and small FoV CBCT datasets. The distances and angulations between the matching implant positions of each repeated registration were used to determine the precision of the registration process. Wilcoxon Signed Rank Paired Tests were used to compare the differences between large FoV and small FoV. The threshold for statistical significance was set at p =.05. Results: Differences in 3D implant position based on the registration precision between small FoV and large FoV present at both the implant entry point (0.37 ± 0.25 mm vs 0.35 ± 0.23 mm, p =.482) and implant tip (0.49 ± 0.34 mm vs 0.37 ± 0.24 mm, p <.001). Differences in overall angular precision were observed between small FOV and large FoV (1.43 ± 1.36° vs 0.51 ± 0.38°, p <.001). Conclusion: CBCT with a small FoV is accompanied by greater precision errors in intra‐oral scan registration. However, when sufficient well‐distributed teeth are visible in small FoV CBCT, the precision of digital intra‐oral scan registration appears to be within clinically acceptable limits for sCAIS. [ABSTRACT FROM AUTHOR]

Aim: To assess, in vitro, variables potentially influencing implant blooming using a human‐like imaging phantom and 3D‐printed mandibles. Material and Methods: Sixty implants were inserted in 3D‐printed mandibles in 26 different configurations in order to examine the impact of implant diameter, presence of a cover screw, implant design/material, implant position, and the presence of additional implants on implant blooming using two cone‐beam computed tomography (CBCT) devices (Accuitomo [ACC] and NewTom [NWT]). Two observers measured the amount of implant blooming in both buccolingual and mesiodistal directions. Inter‐rater agreement and descriptive statistics, grouped by implant characteristic and CBCT device, were calculated. Results: Both CBCT devices increased implant diameter (a mean increase of 9.2% and 11.8% for titanium, 20.3% and 24.4% for zirconium, for ACC and NWT, respectively). An increase in implant diameter did not increase the amount of blooming, whereas placing a cover screw did (from 8.0% to 10.9% for ACC, and from 10.0% to 15.6% for NWT). Moreover, implant design, anatomical region, and the presence of another implant also affected the extent of the blooming. Conclusions: Dental implants show a clear diameter increase on CBCT, with the effect being more pronounced for zirconium than for titanium implants. Similar effects are likely to occur in the clinical setting, potentially masking nonosseointegration, reducing the dimensions of peri‐implant defects, and/or causing underestimation of the buccal bone thickness. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the impact of reducing the radiographic field of view (FOV) on the trueness and precision of the alignment between cone beam computed tomography (CBCT) and intraoral scanning data for implant planning. Materials and Methods: Fifteen participants presenting with one of three clinical scenarios: single tooth loss (ST, n = 5), multiple missing teeth (MT, n = 5) and presence of radiographic artifacts (AR, n = 5) were included. CBCT volumes covering the full arch (FA) were reduced to the quadrant (Q) or the adjacent tooth/teeth (A). Two operators, an expert (exp) in virtual implant planning and an inexperienced clinician, performed multiple superimpositions, with FA‐exp serving as a reference. The deviations were calculated at the implant apex and shoulder levels. Thereafter, linear mixed models were adapted to investigate the influence of FOV on discrepancies. Results: Evaluation of trueness compared to FA‐exp resulted in the largest mean (AR‐A: 0.10 ± 0.33 mm) and single maximum discrepancy (AR‐Q: 1.44 mm) in the presence of artifacts. Furthermore, for the ST group, the largest mean error (−0.06 ± 0.2 mm, shoulder) was calculated with the FA‐FOV, while for MT, with the intermediate volume (−0.07 ± 0.24 mm, Q). In terms of precision, the mean SD intervals were ≤0.25 mm (A‐exp). Precision was influenced by FOV volume (FA < Q < A) but not by operator expertise. Conclusions: For single posterior missing teeth, an extended FOV does not improve registration accuracy. However, in the presence of artifacts or multiple missing posterior teeth, caution is recommended when reducing FOV. [ABSTRACT FROM AUTHOR]

Objectives: To retrospectively evaluate whether repositioning the bone window leads to a better outcome of three‐dimensional sinus augmentation in lateral sinus floor elevation (LSFE) with simultaneous implant placement. Methods: 34 patients with a total of 40 implants (14: test group, 26: control group) receiving LSFE with simultaneous implant placement were included in this retrospective research. CBCT images were taken before surgery, immediately and 6 months after surgery. The two‐dimensional augmentation parameters, including apical bone height (ABH), endo‐sinus bone gain (ESBG), and palatal/buccal bone height (PBH/BBH), and three‐dimensional parameters, including augmentation volume (AV) and palatal/buccal augmentation volume (PAV/BAV), were measured. The lateral defect length (LDL) and lateral window length (LWL) were also measured to evaluate the lateral antrostomy recovery. Results: At the 6‐month follow‐up, the reduction rates at ABH, ESBG, and BBH of the test group (ABH: 10.41% ± 30.30%, ESBG: 2.55% ± 8.91%, BBH: 2.50% ± 8.65%) were significantly lower than those of the control group (ABH: 25.10% ± 22.02%, ESBG: 11.47% ± 9.79%, BBH: 7.10% ± 5.37%; p <.05). In addition, the test group showed better three‐dimensional augmentation stability on the buccal side (BAV reduction: 15.51% ± 10.86% vs. 27.15% ± 12.61%; p <.05). Moreover, the LDL/LWL ratio of the test group was significantly lower than that of the control group (p <.05). Conclusion: Within the limitations of this study, repositioning of the bone window in LSFE with simultaneous implant placement could contribute to endo‐sinus augmentation stability on the buccal side at the 6‐month follow‐up. Moreover, it would also facilitate recovery of the lateral antrostomy defect. [ABSTRACT FROM AUTHOR]

Objectives: To compare radiographic bone changes, following alveolar ridge preservation (ARP) using Guided Bone Regeneration (GBR), a Socket Seal (SS) technique or unassisted socket healing (Control). Material and methods: Patients requiring a single rooted tooth extraction in the anterior maxilla, were randomly allocated into: GBR, SS and Control groups (n= 14/). Cone Beam Computed Tomography (CBCT) images were recorded post‐extraction and at 4 months, the mid‐buccal and mid‐palatal alveolar ridge heights (BARH/PARH) were measured. The alveolar ridge width, cross‐sectional socket and alveolar‐process area changes, implant placement feasibility, requirement for bone augmentation and post‐surgical complications were also recorded. Results: BARH and PARH was found to increase with the SS (0.65 mm ± 1.1/0.65 mm ± 1.42) techniques, stabilise with GBR (0.07 mm ± 0.83/0.86 mm ±1.37) and decrease in the Control (−0.52 mm ± 0.8/−0.43 mm ± 0.83). Statistically significance was found when comparing the GBR and SS BARH (p =.04/.005) and GBR PARH (p =.02) against the Control. GBR recorded the smallest reduction in alveolar ridge width (−2.17 mm ± 0.84), when compared to the Control (−2.3 mm ± 1.11) (p =.89). A mid‐socket cross‐sectional area reduction of 4% (−2.27 mm2 ± 11.89), 1% (−0.88 mm2 ± 15.48) and 13% (−6.93 mm2 ± 8.22) was found with GBR, SS and Control groups (GBR vs. Control p =.01). The equivalent alveolar process area reduction was 8% (−7.36 mm2 ± 10.45), 6% (−7 mm2 ± 18.97) and 11% (−11.32 mm2 ± 10.92). All groups supported implant placement, with bone dehiscence noted in 57% (n = 4), 64%(n = 7) and 85%(n = 12) of GBR, SS and Control cases (GBR vs. Control p =.03). GBR had a higher risk of swelling and mucosal colour change, with SS associated with graft sequestration and matrix breakdown. Conclusion: GBR ARP was found to be more effective at reducing radiographic bone dimensional changes following tooth extraction. [ABSTRACT FROM AUTHOR]

Aim: To validate in vitro the accuracy of a novel method for bone augmentation of horizontal alveolar bone defects with the help of a surgical guide. Material and methods: Six cone‐beam computed tomography scans of patients requiring horizontal bone augmentation were segmented and 3D printed. Two surgeons performed the bone augmentation surgery twice for each case on 3D‐printed models, using either a conventional or guided protocol. Each surgeon virtually planned the desired graft shape beforehand. The resulting grafts were compared linearly and volumetrically to the plan; graft density and surgical time were also analyzed. Results: There was significantly less graft volume outside the planned volume with the guided protocol (36.8% ± 14.1 vs. 19.6% ± 12.3, p <.01). The use of a guide increased graft accuracy at several measurement points, resulting in less overfill when using the guided protocol (1.7 ± 1.7 mm at the most coronal point, 0.2 mm ± 1.4 at 25%, 0.0 mm ± 0.9 at 50%, 0.1 mm ± 1.1 at 75%, and 0.4 mm ± 1.4 apically). Graft thickness was increased 1 mm coronally from the planned graft (2.8 mm ± 2.3 vs. 1.8 mm ± 2.2, p =.04). Surgical time increased significantly when using a guide (a difference of 2 m 26 s). Conclusion: The technique, tested here in vitro, allows surgeons to improve the accuracy of the resulting graft shape, to better compact material in the coronal portion of the graft, and to reduce the amount of graft material placed outside the planned volume. [ABSTRACT FROM AUTHOR]

Aims: The purpose of this study was to evaluate the accuracy of bone‐level assessments using either cone‐beam computed tomography (CBCT), intra‐oral peri‐apical (PA) radiographs or histology following reconstructive treatment of experimental peri‐implantitis. Materials and Methods: Six Labrador dogs were used. Experimental peri‐implantitis was induced 3 months after implant placement. Surgical treatment of peri‐implantitis was performed and peri‐implant defects were allocated to one of four treatment categories; no augmentation, bone graft materials with or without a barrier membrane. Six months later, intra‐oral PA radiographs and block biopsies from all implants sites were obtained. Marginal bone levels (MBLs) were measured using PA radiographs, CBCT and histology. Results: Significant correlations of MBL assessments were observed between the three methods. The measurements in PA radiographs consistently resulted in an overestimation of the bone level of about 0.3–0.4 mm. The agreement between the methods was not influenced by the use of bone substitute materials in the management of the osseous defects. Conclusions: Although MBL assessments obtained from PA radiographs showed an overestimation compared to MBL assessments on corresponding CBCT images and histological sections, PA radiographs can be considered a reliable technique for peri‐implant bone‐level evaluations following reconstructive surgical therapy of experimental peri‐implantitis. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to determine whether distally angulating an implant is a successful strategy to avoid the maxillary sinus and the need for bone augmentation, while increasing the anterior‐posterior (A‐P) implant distribution in the edentulous maxilla. Materials and Methods: In 115 patients with edentulous maxillae, virtual implant planning was performed utilizing cone‐beam computer tomographs. Axial (8 mm length) and tilted (12 mm length) dental implants with 30‐degree and 45‐degree angulation were virtually positioned to avoid entering the maxillary sinus, while maximizing A‐P distribution. Measurements were made between the tilted and axial implants to assess the change in A‐P distribution of implants at the implant and abutment levels. Results: Forty‐seven sites (20.4%) were not able to have either treatment modality with insufficient bone for implant placement. Axial implants were placed more distally than 45‐degree and 30‐degree tilted implants in 24% and 42% of sites, respectively. The average change in A‐P spread measured at the implant level, for 30‐ and 45‐degree tilted implants was −0.25 mm (95% CI −0.76, 0.26) and 1.9 mm (95% CI 1.4, 2.3), respectively. When measured from the center of each multi‐unit abutment the average increase in A‐P distances for tilted implants appears larger in the 30‐degree and 45‐degree groups by 0.97 mm and 1.74 mm, respectively compared to measurements at the implant level. Conclusions: Angulating 12 mm implants provides a limited increase in A‐P distribution of implants in edentulous rehabilitation in most situations. In certain patients, the use of 8mm axial implants may provide a greater A‐P spread. [ABSTRACT FROM AUTHOR]

Objectives: To measure in vivo 3D accuracy of backward‐planned partially guided implant surgery (PGIS) based on dental magnetic resonance imaging (dMRI). Material and Methods: Thirty‐four patients underwent dMRI examinations. Tooth‐supported templates were backward planned using standard dental software, 3D‐printed, and placed intraorally during a cone beam computed tomography (CBCT) scan. Treatment plans were verified for surgical viability in CBCT, and implants were placed with guiding of the pilot drill. High‐precision impressions were taken after healing. The 3D accuracy of 41 implants was evaluated by comparing the virtually planned and definitive implant positions with respect to implant entry point, apex, and axis. Deviations from the dMRI‐based implant plans were compared with the maximum deviations calculated for a typical single implant. Results: Twenty‐eight implants were placed as planned in dMRI. Evaluation of 3D accuracy revealed mean deviations (99% confidence intervals) of 1.7 ± 0.9mm (1.2–2.1mm) / 2.3 ± 1.1mm (1.8–2.9 mm) / 7.1 ± 4.8° (4.6–9.6°) for entry point / apex / axis. The maximum deviations calculated for the typical single implant surpassed the upper bounds of the 99% CIs for the apex and axis, but not for the entry point. In the 13 other implants, dMRI‐based implant plans were optimized after CBCT. Here, deviations between the initial dMRI plan and definitive implant position were only in part higher than in the unaltered group (1.9 ± 1.7 mm [0.5–3.4 mm] / 2.5 ± 1.5 mm [1.2–3.8 mm] / 6.8 ± 3.8° [3.6–10.1°] for entry point / apex / axis). Conclusions: The 3D accuracy of dMRI‐based PGIS was lower than that previously reported for CBCT‐based PGIS. Nonetheless, the values seem promising to facilitate backward planning without ionizing radiation. [ABSTRACT FROM AUTHOR]

Objectives: This randomized controlled trial aimed to compare crestal bone loss (CBL) and buccal bone thickness (BBT) around triangular cross‐section neck (TN) to round neck (RN) implants retaining mandibular overdentures one year after loading, using cone beam computed tomography (CBCT). Material and Methods: Twenty edentulous patients receiving 40 implants with similar diameters were randomly assigned to the RN and TN groups. Clinical buccal bone thickness (CBBT) around the implants was measured with a caliper at baseline. A resonance frequency analyzer was used to measure the implant stability quotient (ISQ) at the baseline and two months after insertion. Pocket probing depths (PPD), plaque index (PI), and gingival index (GI) were also recorded at postoperative months 2, 6, and 12. CBCT was used to evaluate proximal CBL and BBT at three levels (0, −2, and −4 mm) one year after loading. Results: No implant loss was observed during the follow‐up period. No significant differences in CBBT, ISQ values, and scores for PPD, PI, and GI between the two groups were observed at any time (p >.05). BBT was also comparable one year after loading (p >.05). The mean ± SD proximal CBL one year after loading was 0.58 ± 0.36 mm for TN and 0.91 ± 0.59 mm for RN (p <.01). Conclusions: This study found better crestal bone preservation in the implants with the novel neck design than conventional neck design in the anterior mandible after a follow‐up of one year. However, it may not be clinically noticeable. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to explore the feasibility of ultrasonography (US) for clinical imaging of peri‐implant tissues. Material and Methods: Patients with ≥1 implant, a cone‐beam computed tomography (CBCT) scan, an US scan, and clinical photographs taken during the surgery were included. The crestal bone thickness (CBT) and facial bone level (FBL) were measured on both US and CBCT modalities, and direct FBL measurements were also made on clinical images. US measurements were compared with CBCT and direct readings. Results: A total of eight implants from four patients were included. For FBL measurements, US and direct (r2 = 0.95) as well as US and CBCT (r2 = 0.85) were highly correlated, whereas CBCT correlated satisfactorily with the direct reading (r2 = 0.75). In one implant without facial bone, CBCT was not able to measure CBT and FBL accurately. The estimated bias for CBT readings was 0.17 ± 0.23 mm (p =.10) between US and CBCT. US blood flow imaging was successfully recorded and showed a wide dynamic range among patients with different degrees of clinical inflammation. Conclusion: US is a feasible method to evaluate peri‐implant facial crestal bone dimensions. Additional US features, for example, functional blood flow imaging, may be useful to estimate the extent and severity of inflammation. [ABSTRACT FROM AUTHOR]

Objectives: This retrospective study aimed to evaluate the influence of anatomical, patient and surgical factors on the occurrence of membrane perforation (MP) during lateral window sinus floor elevation (LWSFE). Material and methods: A review of LWSFE patient records between 2014 and 2019 accounted for MP occurrence, window surface area (WSA), intravenous sedation use, osteotomy instrument type and clinician experience. Preoperative cone beam computed tomography (CBCT) scans were analyzed for lateral wall thickness (LWT), LFM and LAM angles formed between lateral and medial walls at the floor and anterior wall, respectively, sinus width at 5‐, 10‐ and 15‐mm (LM‐5, LM‐10 and LM‐15) from the floor, residual bone height (RBH), sinus pathologies, septa and arterial anastomoses. The generalized estimating equation (GEE) approach with a sandwich variance–covariance estimator was used to evaluate the associations with MP. Results: MP occurred in 25.74% of 202 LWSFE procedures (166 patients). Mean 1.6 mm‐LWT, 3.2 mm‐RBH, 95°‐LFM, 75.5°‐LAM, 12 mm‐LM‐5, 20.79% septa, 16.83% arterial anastomosis, 37.62% sinus pathology and 29.21% intravenous sedations, 85.24% WSA ≥ 40 mm2 and 57% >10 procedures/clinician were reported. Greater MP rates were encountered as follows: 38.3% (LWT ≥ 1.5 mm), 38% (LFM < 90°), 59.6% (LAM < 70°), 45.4% (LM‐5 < 10 mm) and 36.4% (WSA ranged > 80 mm2), with statistically significant associations with all these outcomes (p <.05). The presence of pathologies was also associated with MP (p =.013). Associations between MP and the presence of septa and arterial anastomoses, age/gender, right/left sinus, RBH, clinician's experience, instrument type and intravenous sedation use could not be demonstrated. Conclusions: MP is significantly associated with thicker lateral walls, narrower sinuses, larger windows and existing sinus pathology. [ABSTRACT FROM AUTHOR]

Objectives: To radiographically evaluate the effect of the adjunctive use of tenting screws (TS) for primary horizontal guided bone regeneration (GBR). Materials & Methods: Twenty‐eight patients in need of staged bone augmentation were consecutively treated in a private practice. A xenogenic particulate bone substitute material (DBBM) and a resorbable collagen membrane were used in all patients. Subjects were divided into two groups: control (conventional GBR; n = 22) and test (tenting screws in conjunction with GBR ‐ TS; n = 22). CBCT images were obtained before augmentation and after 6–8 months. CBCTs were superimposed, and linear horizontal measurements were performed. Alveolar ridge width (RW) and ridge width change (RWchange) were assessed at 1, 3, 5, and 7 mm below the bone crest. Results: Forty‐four sites in 28 patients were evaluated. No differences between the groups were detected for RW at baseline (TS: 5.87 ± 2.41; control: 5.36 ± 1.65). Regarding RWchange, TS promoted an additional effect at 1 and 3 mm below the crest compared to control (p <.05; RWchange‐1 TS: 3.72 ± 2.46; control: 1.25 ± 3.05; RWchange‐3 TS: 3.98 ± 2.53; control: 2.50 ± 2.02). The final RW was greater in group TS compared to the control group at the 1, 3, and 5 mm level (p <.05). Conclusions: The use of tenting screws exerted a positive effect on staged GBR with a greater final RW at the 3 mm level. In addition, GBR in conjunction with TS was able to provide consistent bone augmentation at lingual/palatal sites. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the diagnostic accuracy of cone beam computed tomography (CBCT) for the diagnosis of peri‐implant bone defects of titanium (Ti), zirconium dioxide (ZrO2) or titanium–zirconium (Ti–Zr) alloy implants. Materials and Methods: Ti, Ti–Zr or ZrO2 implants with two diameters (3.3 mm, 4.1 mm) and one length (10 mm) were inserted in the angle of the mandible of six fresh defrosted pig jaws. Out of the 12 implants inserted, 6 served in the test group with standardized buccal peri‐implant bone defects, whereas 6 served as control without bone defects. CBCTs were performed with three acquisition protocols (standard, high and low dose) using two devices. Four observers analysed CBCTs as follows: (a) presence of a peri‐implant defect; (b) presence of peri‐implant artefacts and impact on defect diagnosis; and (c) linear measurements of buccal peri‐implant defect including height and width (in mm). Results: CBCT device, CBCT settings, implant material, implant diameter and observer background did not significantly influence diagnostic accuracy. The sensitivity and specificity values were high for defect detection. ZrO2 led to a lower than average diagnostic accuracy (0.781). The linear measurements of peri‐implant defect were underestimated by <1 mm on average. The subjective impact of artefacts on defect diagnosis was significantly affected by implant material and observer background. Conclusions: CBCT showed high diagnostic accuracy for peri‐implant bone defect detection regardless of the device, imaging setting or implant material used. If CBCT is indicated to assess peri‐implant bone disease, low dose protocols could be a promising imaging modality. [ABSTRACT FROM AUTHOR]

Objectives: To compare ear, nose, and throat (ENT) specialists and dentists assessing health or pathology of maxillary sinuses using cone beam computed tomography (CBCT). Material and methods: Two ENT specialists and two oral surgeons assessed 100 CBCT datasets of healthy patients referred for dental implant placement in the posterior maxilla and decided on the possibility of sinus floor elevation or the necessity for further diagnostic examinations based solely on radiographic findings. Inter‐rater agreements within the same specialty were calculated with Cohen's kappa and overall agreements with Fleiss kappa, and factors influencing the decisions taken were evaluated using regression analyses. Results: The correlation between all four raters was generally fair to moderate. The intra‐specialty comparison showed a lower correlation between dentists than between ENT specialists. Absence of membrane thickening and total or subtotal sinus opacification showed the highest predictive value for a consensus in favor of sinus floor elevation and ENT referral, respectively. Flat membrane thickening with an irregular surface morphology was associated with disagreement between the examiners. Dome‐shaped membrane thickenings were often considered as to be referred by dentists but not by ENTs. Conclusion: The assessment of maxillary sinuses using CBCT imaging exhibited unsatisfactory agreement between ENT specialists and oral surgeons. Referral guidelines based on accidental CBCT findings that aim to diagnose relevant sinus pathologies early and avoid unnecessary diagnostics and/or therapies are needed, and an initial proposal for such recommendations is provided. Further research on correct interpretation of sinus findings and a validation of the present recommendations are required. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this cone beam computed tomography (CBCT) study was to describe facial alveolar bone alterations and gray value (GV) changes around implants in aesthetic anterior maxilla with simultaneous guided bone regeneration (GBR) and to investigate potential influence of factors related to vertical alveolar bone stability, such as particle sizes of the deproteinized bovine bone mineral (DBBM) used. Materials and Methods: A retrospective study design was adopted. Four facio‐palatal cross‐sectional CBCT images of 166 implants from 124 patients who had maxillary anterior implants were obtained. Measurements of the vertical facial alveolar bone level (VFBL), horizontal facial alveolar bone thickness (HFBT), and GV were identified of 1–3 years. Then, correlation coefficients for those parameters were calculated. Finally, linear mixed models were established to investigate potential factors influencing vertical alveolar bone resorption. Results: Facial alveolar bone underwent fast bone modeling and remodeling during the first 6 months, with decreases of 1.00 ± 1.19 and 0.74 ± 0.86 mm in VFBL and HFBT in implant shoulder, respectively, and there was positive and significant correlation between the alterations in VFBL and HFBT1 (rs =.516, p =.000). Linear mixed models identified particle size of DBBM as a critical factor associated with vertical bone resorption (p =.000). The GV gradually increased during the follow‐up period. Conclusions: Rapid and unavoidable peri‐implant bone resorption usually happened during the first 6 months after implant placement. GBR is a predictable treatment for maxillary anterior implants, since GV has an increasing trend. Large bone particles of DBBM help maintain vertical alveolar bone stability. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this split‐mouth randomized controlled clinical trial was to compare the deviations of planned and placed implants placed by the assistance of a micron tracker‐based dynamic navigation device or freehand methods. Material and methods: A thermoplastic fiducial marker was adapted on the anterior teeth, and cone‐beam computerized tomography was used for imaging. A minimum of one implant was planned for each side of the posterior maxilla, and the dynamic navigation device or freehand method was randomly used for surgical insertion. Deviations were measured by matching the planning data with a final CBCT image. Linear deviations (mm) between the planned and placed implants were the primary outcome. The results were analysed by generalized linear mixed models (p <.05). (NCT03471208). Results: A total of 92 implants were placed to 32 volunteers, and 86 implants were included in the final analysis. For the linear deviations, mean of differences (Δ) was 0.72mm (Standard deviation (SD): 0.26); (95% Confidence interval (CI): 0.39–1.02) in the shoulder of the implants (p <.001) and 0.69mm (SD: 0.36); (95% CI: 0.19–1.19) in the tip of the implants (p <.001). For the angular deviations, Δ was 5.33° (SD: 1.63); (95% CI: 7.17–3.48); (p <.001). Conclusions: The navigation technique can be used to transfer virtual implant planning to the patient's jaw with increased accuracy. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between preoperative trabecular bone structure and implant outcome based on bone morphometric bone parameters from CBCT scans. Materials and Methods: Twenty consecutive cases with early implant failure in the posterior region of the mandible were matched with 20 control patients with a successful implant osseointegration selected. All patients had taken a preoperative CBCT image according to a standardized acquisition protocol. On these CBCT scans, the trabecular bone of each implantation site was selected and segmented, after which 3D morphometric bone parameters were calculated and used in a cluster analysis to objectively differentiate trabecular bone patterns. Fisher's exact test was used to determine whether there is a significant association between trabecular pattern and implant outcome. Results: A sparse, intermediate, and dense trabecular bone pattern was distinguished by cluster analysis. The relationship between the trabecular bone pattern and early implant failure was significant (z = 9.6; p <.05). Early implant failure was more likely to occur in the sparse bone types, while implant survival was associated with intermediate bone types. Conclusion: Prior to implant placement, attention should be given to extreme deviations in trabecular structure at the planned implant sites. Very sparse or very dense bone should be carefully evaluated at the potential implant site, while intermediate bone types seem favorable for implant survival. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the in vitro diagnostic accuracy of low‐dose cone‐beam computed tomography (LD‐CBCT) for the detection, classification, and measurement of peri‐implant bone lesions. Material and methods: Titanium dental implants with all‐ceramic single crowns (n = 24) were inserted into bovine bone. At twelve implants, four types of peri‐implant bone lesions were created. Radiographic imaging was performed using three techniques: LD‐CBCT, high‐definition CBCT (HD‐CBCT), and intraoral radiography (IR). The datasets were presented twice to four observers in a random order. Diagnostic accuracy was measured by calculating sensitivity and specificity, and analyzed using the McNemar's test at a significance level of 0.05. Absolute agreement between the defect sizes was assessed by means of intraclass correlation coefficients (ICC). Results: For all three techniques, diagnostic accuracy and reliability for the detection of defects were almost perfect. The following order was found for classification of the different defect types (sensitivity/specificity): HD‐CBCT (0.96/0.99) > LD‐CBCT (0.93/0.98) > IR (0.71/0.95). No significant difference was found between the two CBCT techniques. Their performance was superior to that of IR. With regard to absolute agreement of defect size, LD‐CBCT agreement with HD‐CBCT (ICC, 95% confidence interval) was slight for defect depth (0.342, 0.181–0.625) and substantial for defect width (0.911, 0.775–0.963). Conclusion: Intraoral radiography is useful for detecting peri‐implant bone lesions. LD‐CBCT provides additional information regarding the geometry of defects. The even higher diagnostic accuracy of the HD‐CBCT protocol tested needs to be carefully weighed against its radiation dose, which is 14 times higher than that of LD‐CBCT. [ABSTRACT FROM AUTHOR]

Objectives: To assess through cone‐beam computed tomography (CBCT) buccal alveolar bone alterations after immediate implant placement using the following techniques: open flap and grafting (flap‐graft), open flap and no grafting (flap‐nograft) and flapless and no grafting (noflap‐nograft). Materials and methods: This was a three‐armed parallel group randomized clinical trial with allocation ratio 1:1:1. Patients were eligible in case they needed immediate implant replacing teeth in maxillary premolar area, with sufficient buccal bone support. CBCT was performed immediately after the intervention and 6 months later. The main outcomes were CBCT measurements performed at apical (A‐EA), medial (M‐EM) and external and internal implant bevel level (B‐EB, B‐IB) and vertical defect depth (DP). Pain and discomfort, time of surgery and complications were recorded. Differences between groups were estimated through ANOVA tests and post‐hoc Scheffe's analysis for pairwise comparisons. Multiple regressions were conducted to estimate influence of gingival biotype and baseline marginal gap dimension. Results: Forty‐five patients were recruited and randomized to treatments with one lost to follow‐up. Analysis of variance showed that the effect of treatment technique was not relevant for all horizontal and vertical outcomes. The three techniques exhibited almost complete fill of marginal gap, with a mean residual vertical gap of 0.27 mm and horizontal gap of 0.5 mm. Regression models indicated a positive effect of thick biotype on gap filling and dimensional bone reduction. The noflap‐nograft technique resulted less painful. Conclusions: The option of noflap‐nograft surgery in post‐extraction implants allows for minimal surgical intervention with comparable buccal bone changes and gap filling after a follow‐up of 6 months in sites with sufficient buccal bone support. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this prospective cohort study was to evaluate computer‐guided implant surgery with tooth‐supported drill guides based on CBCT scans and intraoral scanning. Materials and methods: For partially edentulous patients, a prosthetic and surgical planning was completed in the guided surgery software (coDiagnostiX) and drill guides were 3D‐printed accordingly. Three months after implant placement, an intraoral scan of the implant's position was used to evaluate the accuracy of placement using the coDiagnostiX treatment evaluation tool. Deviations were reported in degrees and in distance at implant's entry point and apex. Several risk factors, which might influence the accuracy, were evaluated separately: treated jaw, flap design, prior augmentations, amount of unrestored teeth, crowding, location of implants, cortical interference, and implant's length and diameter. Results: A total of 66 patients received 145 Straumann tissue level implants that were eligible for accuracy analysis. The mean angular deviation was 2.72° ± 1.42. The mean three‐dimensional deviation at the implant's entry point was 0.75 mm ± 0.34. At implant's apex, the mean was 1.06 mm ± 0.44. The amount of unrestored teeth (p = .002 & p = .003), the implant's location (p < .001), the implant's length (p = .004), and cortical interference (p = .033) had a significant influence on the accuracy of placement. Implant survival was 99.3% (n = 1 failed implant) at 12 and 24 months. Conclusions: Guided surgery with tooth‐supported drill guides made in a digital workflow is a feasible treatment option. However, deviations do occur and the implant's length, location, cortical interference and the amount of unrestored teeth have a significant influence on the accuracy. [ABSTRACT FROM AUTHOR]

Objectives: To test whether block bone substitute used for guided bone regeneration (GBR) of peri‐implant defects leads to different thickness of the augmented hard tissue than particulate bone substitute. Material and methods: In 24 patients, 24 two‐piece dental implants were placed >4 months after tooth extraction. Following random allocation, 12 peri‐implant bone dehiscences were grafted with an individually shaped block of deproteinized bovine‐derived bone mineral (DBBM) and 12 bone dehiscences with particulate DBBM. All the sites were covered with a collagen membrane stabilized with resorbable pins. Immediately after wound closure and after 6 months, the horizontal thickness (HT) of the augmented hard tissue was measured at the level of implant shoulder using ‐computed tomography. Results: After wound closure, the median HT measured 3.35 mm (mean: 3.38) in the block group and 2.85 mm (mean: 2.73) in the particulate group. At 6 months, the median HT decreased to 2.90 mm (mean: 2.71) in the block group and to 0.2 mm (mean: 0.52) in the particulate group. This difference was statistically significant (p < .001). Conclusions: Block bone substitute used for GBR of peri‐implant defects was superior to particulate bone substitute regarding the dimension of the augmented hard tissue after 6 months of healing. [ABSTRACT FROM AUTHOR]