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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: 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]

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]

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 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: 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]

Abstract: Objectives: The aim of this study was to compare bone block grafts fixed at a distance (BBG‐D) with the SonicWeld Rx shell technique (Poly‐D‐L‐Lactide foil fixed at a distance, augmented with autogenous and deproteinized bovine bone particles (SWST)) for lateral alveolar ridge augmentation. Methods: In this single‐blinded, randomized, controlled trial, 30 patients with a bucco‐palatal bone width of ≤3 mm were randomized into the treatment groups: “BBG‐D” and “SWST”. Bone width was measured with cone beam computed tomography (CBCT). One implant was placed at each grafted site. Frequencies of complications, bone gain and bone resorption in the CBCT were assessed as outcomes. Results: Fifteen sites were augmented in each treatment group. One graft (7%) in the BBG‐D group and five (33%) in the SWST group were lost (p = 0.17). In the SWST group, two implants (20%) were lost and none in the BBG‐D group (p = 0.18). The rate of pooled severe complications (loss of graft and/or implant) was different (p = 0.035). Five (33%) wound dehiscences happened in the SWST group and none in the BBG‐D group (p = 0.042). Seven (47%) nonsevere complications (wound dehiscence, inflammation, transient nerve injury) happened in the SWST group and one (7%) in the BBG‐D group (p = 0.035). At the one‐year evaluation, there were no significant differences in bone loss at the mesial, distal or buccal implant shoulder between treatment groups. Conclusions: Within the limitations of this study, the BBG‐D method remains the gold standard for lateral alveolar ridge augmentation compared to the shell technique because of the lower complication rates. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The aim of this split‐mouth randomized controlled study was to evaluate radiographic dimensional changes after tooth extraction in posterior sites treated with a ridge preservation technique or left for spontaneous healing. Materials and Methods: In a total of 18 patients, tooth extraction in posterior sites of the upper and lower jaw was performed in a split‐mouth design. The post‐extraction sockets were randomly assigned to the following two treatment modalities: deproteinized bovine bone mineral (DBBM) with 10% collagen (DBBM‐C) covered with a native bilayer collagen membrane (NBCM) (test group) and spontaneous healing (control group). Cone beam computed tomography (CBCT) scans were performed after extractions, 3 and 6 months later. The following parameters were measured: the height of the buccal bone plate (BH), height of the palatal bone plate (PH), horizontal width of the extraction socket at 1 mm, 3 mm, and 5 mm (HW‐1, HW‐3, HW‐5), and the horizontal width (thickness) of the buccal bone plate at 1 mm, 3 mm, and 5 mm (BHP‐1, BHP‐3, BHP‐5). Statistical analysis was performed applying a nonparametric Wilcoxon signed‐rank test. Results: The CBCT analysis showed a bone loss compared to baseline in test and control group. The measurements which have reached statistically significant differences at 6 months were BH (test: −2.31% vs control: −13.11%), PH (test: −2.07% vs control: −15.32%), HW‐1 (test: −17.14% vs control: −32.47%), and HW‐3 (test: −11.65% vs control: −28.47%). Conclusions: The posterior ridge preservation technique using DBBM‐C covered with a NBCM is a valid approach reducing the amount of the radiographic loss in alveolar ridge dimensions. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The aim of this multicenter prospective study was to analyze clinically and histologically the influence of sinus cavity dimensions on new bone formation after transcrestal sinus floor elevation (tSFE). Material and Methods: Patients needing maxillary sinus augmentation (residual crest height <5 mm) were treated with tSFE using xenogeneic granules. Six months later, bone‐core biopsies were retrieved for histological analysis in implant insertion sites. Bucco‐palatal sinus width (SW) and contact between graft and bone walls (WGC) were evaluated on cone beam computed tomography, and correlations between histomorphometric and anatomical parameters were quantified by means of forward multiple linear regression analysis. Results: Fifty consecutive patients were enrolled and underwent tSFE procedures, and forty‐four were included in the final analysis. Mean percentage of newly formed bone (NFB) at 6 months was 21.2 ± 16.9%. Multivariate analysis showed a strong negative correlation between SW and NFB (R2 = .793) and a strong positive correlation between WGC and NFB (R2 = .781). Furthermore, when SW was stratified into three groups (<12 mm, 12 to 15 mm, and >15 mm), NFB percentages (36%, 13% and 3%, respectively) resulted significantly different. Conclusions: This study represented the first confirmation based on histomorphometric data that NFB after tSFE was strongly influenced by sinus width and occurred consistently only in narrow sinus cavities (SW <12 mm, measured between buccal and palatal walls at 10‐mm level, comprising the residual alveolar crest). [ABSTRACT FROM AUTHOR]

Aim To test whether an equine bone substitute block used for guided bone regeneration ( GBR) of peri-implant defects differs from bovine block or particulate bone substitutes regarding the hard and soft tissue contours of the augmented ridge. Material & Methods Two semi-saddle bone defects were prepared in each side of the mandible of eight dogs, and one titanium implant was inserted into every defect. The defects were randomly allocated to receive one of the following treatments: bone augmentation by GBR using (1) particulate deproteinized bovine bone mineral ( DBBM) + a collagen membrane ( CM), (2) block DBBM + CM, (3) equine bone substitute block + CM, and (4) empty controls. After 4 months, the jaws were scanned by means of cone beam computed tomography ( CBCT). CBCT analysis was performed in one central and two lateral (mesial and distal) regions of interest ( ROI) of each site evaluating the horizontal thickness of the augmented hard tissue ( HThard tisue) and the total thickness of hard and soft tissue ( HTtotal). The Wilcoxon-Pratt signed rank test was used for statistical analysis. Results In the majority of ROIs, equine and bovine blocks rendered significantly higher values in HThard tissue and HTtotal than controls ( P < 0.05). Generally, equine blocks reached the highest values in HThard tissue and HTtotal followed by DBBM blocks and particulate DBBM. The differences in HThard tissue and HTtotal between GBR groups were not statistically significant ( P > 0.05). In the central ROI, HThard tissue at the level of the implant shoulder measured 1.7 ± 1.4 mm for equine blocks, 1.7 ± 1.0 mm for DBBM blocks, 0.9 ± 1.2 mm for particulate DBBM, and 0 ± 0 mm for controls. The corresponding values in the lateral ROI reached 1.9 ± 1.1 mm for equine blocks, 1.2 ± 0.8 mm for DBBM blocks, 1.0 ± 0.9 mm for particulate DBBM, and 0 ± 0 mm for controls. Conclusions GBR with bone substitute blocks lead to higher ridge dimensions than empty controls. The equine block with CM rendered the most favorable outcomes in hard and soft tissue contours followed by DBBM block and DBBM granulate with CM. [ABSTRACT FROM AUTHOR]

Objectives Given that the nature and presence of voids present within grafted sinuses following maxillary sinus elevation procedures were not known, nor was the contribution of these factors to implant success, the purpose of this study was to investigate these parameters and their relationship to implant success. Materials and Methods This study evaluated data from 25 subjects who had a lateral window maxillary sinus augmentation procedure. Cone-beam computed tomography ( CBCT) was performed at baseline and 4 months after surgery. CBCT images were used to evaluate grafted sites prior to implant placement. Using CBCT images, three examiners independently measured bone-grafted areas ( BG), void areas (V), and percentage of void areas (V%) from six different sections within grafted sites. The six sections were defined as a cross-sectional ( CS) midpoint, CS mesial point, CS distal point, horizontal section ( HS) low point, HS midpoint, and HS high point. Implant success was also determined. Results The calculated V% (V/ BG) for the CS midpoint, CS mesial point, CS distal point, HS low point, HS midpoint, and HS high point were 5.30 ± 6.67%, 5.79 ± 8.51%, 6.67 ± 7.12%, 2.07 ± 2.56%, 5.30 ± 6.62%, and 4.92 ± 5.17% respectively. Implant success after 6 months of follow-up approximated 100%. Conclusions Although voids within grafts varied in terms of distribution and size, the V% within the HS low point were significantly smaller compared to those within the CS midpoint and CS distal point, which had the most intra-subject V%. Thus, more attention should be given to the distal aspect of the sinus when compacting graft materials in the lateral wall sinus augmentation procedure. Implant success was not influenced by the existence of voids as implant success remained high. [ABSTRACT FROM AUTHOR]

Aim The aim of this pilot study was to analyze the interfurcal bone height in relation to the possible need for subsequent sinus floor elevation in patients with advanced periodontitis and furcation involvement of first and/or second maxillary molars. Material and methods Seventeen dentate patients, who received cone beam computed tomography ( CBCT) for detailed preoperative diagnosis and planning of surgical interventions at periodontally involved maxillary molars (17 first and 15 second molars), were consecutively recruited for the study. The minimal bone height in the interfurcal region was measured from CBCT and related to furcation involvement, residual bone above the root tips, and the clinical probing pocket depth ( PPD). Results The minimal interfurcal bone height measured 4.1 ± 2.6 mm on average with 75% of maxillary molars having ≤6 mm and almost 60% having only ≤4 mm bone height left below the sinus floor. A higher risk for reduced interfurcal bone height of ≤4 mm was given when residual PPD of ≥6 mm was remaining at two or more tooth sites (OR 0.10; 0.11). Conclusions The majority of periodontally involved maxillary molars had a substantially reduced interfurcal bone height, particularly with at least two sites with residual PPD ≥ 6 mm. This was a predictor for a subsequent need for sinus floor elevation when tooth replacement with a dental implant is desired. [ABSTRACT FROM AUTHOR]

Objectives Sandwich bone augmentation ( SBA) has been proposed to augment the width of edentulous ridges for implant placement. This study aimed to investigate the effect of a membrane on SBA for the regeneration of buccal implant dehiscence defects. Material and methods Twenty-six healthy patients, each with a single defect, were randomly assigned into two groups. Both groups received an inner and outer layer of mineralized human cancellous and cortical particulate allograft. In the test group, a bovine pericardium membrane covered the bone grafts, while no membrane was placed in the control group. Cone beam computed tomography ( CBCT) scans were taken before and immediately after implant placement and at 6 months post-surgery. Results All implants placed were successfully osseointegrated at 6 months. Clinical re-entry measurements showed significant buccal bone gain in the test group compared with the control group ( P < 0.05). The test group had 1.12, 2.21 and 2.44 mm more buccal bone thickness at 2, 4 and 6 mm below the bone crest. There were no significant differences in the mid-buccal vertical bone height, defect height and width reductions and bone fill between the two groups ( P > 0.05). Cone beam computed tomography analysis demonstrated significant buccal bone gain of 1.22 mm in the test group. Radiographic vertical bone loss at 1-year post-surgery showed no significant differences between the groups. Conclusion Sandwich bone augmentation is a predictable technique for regenerating buccal bone on implant dehiscence defects. Addition of a barrier membrane prevented significant horizontal buccal bone resorption as space was maintained more effectively when compared with sites treated without a membrane. [ABSTRACT FROM AUTHOR]

Objectives The present study evaluated the clinical validity of cone-beam computed tomography ( CBCT) scans in comparison to panoramic radiographs regarding preoperative implant planning in combination with sinus grafting procedures. Materials and methods Preoperative assessment of the maxillary sinuses and implant planning using panoramic radiographs and CBCT scans was performed on 16 sinuses (13 patients) and comprised choice of treatment, timing of implant placement, sinus morphology, level of confidence, complication prediction and graft volume assessment. Six examiners were involved in the study. Results In the majority of cases there was a concordance between the treatment type based on either panoramic radiographs or CBCT. If any difference was found, this was due to an overestimation of bone quantity and quality on panoramic radiographs. The assessment of sinus morphology showed a significantly higher detection rate of sinus mucosal hypertrophy on CBCT. The most appealing result is a significant increase in surgical confidence and a significantly better prediction of complications when using CBCT. Conclusions A preoperative planning based on CBCT seems to improve sinus diagnostics and surgical confidence. [ABSTRACT FROM AUTHOR]