Background: Immediate implant placement (IIP) has shown predictable outcomes when specific requirements are met. The aim of the present study was to radiographically evaluate the dimensions of mandibular incisors and the alveolar bone to further determine the feasibility of IIP in this area. Materials and methods: A total of 404 intact mandibular incisor CBCT images from 101 patients (42 males, 59 females; mean age 49 ± 16.84 years) were analyzed. The mesiodistal tooth width and the distance between the incisal edge (IE), cementoenamel junction (CEJ), facial bone crest (BC), root apex (RA), and fenestration point (F) were registered, together with the alveolar bone width at 1 and 3 mm below BC. Finally, the angular discrepancy between the dental and the alveolar bone long axis (BLA) was recorded as the tooth torque (TT). Results: The CEJ to BC distance was 3.23 ± 1.67 mm. The RA to F mean distance was 15.02 ± 3.97 mm. The mean alveolar bone buccolingual widths at 1 and 3 mm below the facial BC were 7.12 ± 0.82 and 6.32 ± 0.71 mm in the lateral and central incisors, respectively (P 0.001). The buccolingual width was less than 6 mm in more than 33% of the central incisors, but only in 3% of the lateral incisors, displaying increased alveolar width. The average was 165.66 ± 7.47 degrees. Conclusions: The results presented in this study point toward the need for careful consideration of the requirements for anterior mandibular IIP for success and predictability purposes. Schlagwörter: immediate implant placement, implantology, mandibular alveolar bone, mandibular anatomy, restorative dentistry

Hintergrund: Die Sofortimplantation kann vorhersagbare Ergebnisse liefern, sofern bestimmte Voraussetzungen erfüllt sind. Ziel der vorliegenden Studie war eine Röntgenanalyse der Dimensionen der unteren Schneidezähne und ihres Alveolarknochens, um die Durchführbarkeit von Sofortimplantationen in dieser Region zu bewerten. Material und Methoden: DVT-Bilder von insgesamt 404 intakten UK-Schneidezähnen bei 101 Patienten (42 Männer, 59 Frauen, mittleres Alter 49 ± 16,84 Jahre) wurden analysiert. Gemessen wurden die mesiodistale Zahnbreite und die Distanzen zwischen der Schneidekante (SK), der Schmelz-Zement-Grenze (SZG), dem (vestibulären) Knochenkamm (KK), der Wurzelspitze (WS) und dem Fenestrationspunkt (FP). Außerdem wurde die Winkelabweichung zwischen der Zahn- und der Knochenlängsachse als Zahn­torque (ZT) aufgezeichnet. Ergebnisse: Der Abstand SZG–KK betrug 3,23 ± 1,67 mm. Der mittlere Abstand WS–FP lag bei 15,02 ± 3,97 mm. Die mittlere vestibuloorale Breite im Bereich der seitlichen und mittleren Schneidezähne, gemessen 1 und 3 mm apikal des KK, war 7,12 ± 0,82 mm bzw. 6,32 ± 0,71 mm (p 0,001). Die vestibuloorale Breite lag an mehr als 33 % der mittleren Schneidezähne, aber nur an 3 % der seitlichen Schneidezähne bei unter 6 mm, was zeigt, dass die Alveolarkammbreite nach distal zunimmt. Der durchschnittliche ZT betrug 165,66 ± 7,47°. Schlussfolgerungen: Die Ergebnisse der vorliegenden Studie zeigen, dass die Voraussetzungen für eine Sofortimplantation in der UK-Schneidezahnregion sorgfältig geprüft werden müssen, um eine erfolgreiche Behandlung mit vorhersagbaren Ergebnissen sicherzustellen. Schlagwörter: digitale Volumentomografie, Implantologie, restaurative Zahnmedizin, Sofortimplantation, UK-Anatomie, UK-Alveolarknochen

Purpose: To determine the vertical space required for implant osteotomy preparation when utilizing a CAD/CAM fully guided surgical template. Materials and Methods: A total of 14 surgical osteotomy drills (individual and sequential drills) were collected and measured individually using a digital caliper, as well as the total length when the drills were positioned in a surgical handpiece. The height of the surgical guide sleeves and the offset of 14 implant systems in the market were also collected. Results: The vertical dimension of the drills included in this study ranged from 28.2 to 46.3 mm. When these drills were inserted into the handpiece, the total length ranged from 30.0 to 49.5 mm. The height of the surgical guide sleeve and the offset required for the guide had a range of 3.2 to 7.0 mm and 5.0 to 13.5 mm, respectively. This dimension resulted in the total vertical space required for CAD/CAM fully guided surgical templates for each implant system, which ranged from 30.0 to 58.5 mm. Conclusions: Limited mouth opening can pose challenges and limitations in both guided and nonguided dental implant surgery. It can affect the accessibility of surgical implant placement and may result in increased patient discomfort, surgical implant positioning errors, and postoperative complications. Clinicians should determine the patient’s mouth opening capabilities during the treatment planning phase prior to deciding on the appropriate implant system to be used and the implant placement technique.

Successful rehabilitation of severely atrophic, short-span edentulous ridges in esthetic regions can seldom be done without some form of vertical ridge augmentation (VRA). The best available evidence shows that guided bone regeneration procedures may present a very predictable option with reduced potential for complications compared to alternative options. The present case series presents a novel technique to achieve predictable VRA with a low complication rate using tenting screws and cross-linked resorbable membranes. A total of 10 patients (5 men, 5 women) with severe vertical defects in the esthetic zone participated in this study. Following a mean healing time of 9.3 months, the mean defect resolution was 80%, with a mean vertical bone gain of 6.2 ± 1.61 mm. Only one case presented with reduced defect resolution (50%); however, the bone gain for this case was 6 mm.

Purpose: To assess site-related features of peri-implantitis occurring adjacent to teeth and its association with the proximal periodontal bone level. Materials and Methods: Periapical radiographs were collected from partially edentulous patients exhibiting peri-implantitis adjacent to teeth. The following variables were quantified: intrabony defect width (DW), implant marginal bone loss (MBLi), tooth marginal bone loss (MBLt), implant-tooth distance (ITd), intrabony defect angulation (DA), adjacent periodontal bone peak height (ABPh), and implant-tooth angulation (ITa). A correlation matrix using the Spearman correlation coefficient was created to explore the dependence of these variables. Univariate linear regression analysis was carried out by means of generalized estimating equations (GEE), using MBLt as dependent variable. Results: Overall, 61 patients and 84 implants were included in this study, consisting of a total of 105 implant sites facing adjacent teeth. This resulted in 515 linear and 194 angular measurements. A total of 11 different statistically significant associations were demonstrated between the different variables analyzed. Moreover, the univariate regression analysis revealed significant positive associations between MBLt and MBLi (P = .013) and between MBLt and periodontitis (PD) (P = .014). These associations were confirmed in the multivariate model. Conclusions: Teeth adjacent to untreated peri-implantitis lesions are associated with proximal loss of periodontal support. This finding is more remarkable in scenarios that display short implant-tooth distance. Schlagwörter: peri-implantitis, peri-implant diseases, dental implant, periodontal disease, periodontitis

This retrospective study investigates the efficacy of the socket shield (SS) in preserving inter-implant papilla and bone in anterior adjacent implant sites. Clinical and radiographic records of 23 patients were evaluated. A total of 31 implants were placed immediately into extraction sockets with SS, resulting in 26 inter-implant sites, and 7 implants were placed without SS. After a mean follow-up of 41.5 months (range: 12 to 124 months), 30/31 (96.8%) implants with SS and 7/7 (100%) implants without SS were clinically successful. The mean changes in inter-implant papilla and bone heights were –0.40 mm and –0.46 mm, respectively. The effects of implant placement timing and the socket shield number, shape, and crestal level on inter-implant tissue height changes were found to be insignificant (P > .05). Supracrestal shield level (31.6% vs 16.6% in equicrestal), U-shape shield (41.2% vs 7.1% in C-shape), and shield-to-implant contact (40.0% vs 12.5% in no contact) were associated with increased occurrence of exposures. The application of SS in adjacent anterior implant situations is a viable treatment option for maintaining inter-implant papilla.

Maintaining facial soft tissue contour and inter-implant papilla are challenging for implants in the esthetic zone. To counteract the inevitable hard and soft tissue changes after tooth extraction, the socket shield technique (SST) has been advocated as means to maintain the facial and/ or interproximal osseous and gingival architecture. Because SST is a technique-sensitive procedure, various complications related to SST have been reported. This article presents a unique complication after a socket shield procedure and a novel management of the complication.

Purpose: The purpose of this cone beam computed tomography (CBCT) study was to investigate the probability of using straight screw-channel screw-retained restorations following an immediate implant placement and provisionalization protocol in maxillary anterior teeth utilizing implant planning software. Materials and methods: A retrospective review of CBCT images was done. The midsagittal images of maxillary anterior teeth (right canine to left canine) were created in implant planning software, screen-captured, and transferred to a presentation program. The digital implant templates were created for 3.5-mm-diameter (used for central and lateral incisors) and 4.5-mm-diameter (used for central incisors and canines) tapered implants with lengths of 13, 15, and 18 mm. The frequency percentages of immediate implant placement and provisionalization and immediate implant placement and provisionalization with straight screw-channel screw-retained restorations were recorded and compared among all maxillary anterior teeth. Results: CBCT images from 1,200 teeth were evaluated. The overall frequency percentages of immediate implant placement and provisionalization and immediate implant placement and provisionalization with straight screw-channel screw-retained restoration were 84% (range = 74% to 92%) and 14% (range = 10% to 24%), respectively. Conclusion: Although the probability of being able to employ immediate implant placement and provisionalization with a straight screw-channel screw-retained restoration in the esthetic zone is low, the use of smaller-diameter implants can substantially increase the probability. Schlagwörter: cone beam computed tomography, dental implantation, dental implants, esthetics, immediate placement, prosthodontics

The peri-implant soft tissue seal consists of a connective tissue cuff and a junctional epithelium that is different from the arrangement of periodontium around a natural tooth. However, the peri-implant soft tissue complex lacks Sharpey's fibers, thus offering less resistance to clinical probing and biofilm penetration compared to the natural dentition. Therefore, the proper restorative emergence profile design is essential to facilitate favorable esthetic outcomes and maintain periimplant health. The aim of this article is to review the currently available evidence related to the design of subgingival (critical and subcritical) and supragingival contours of the implant restorative emergence profile (IREP) as well as provide a flowchart for decision-making in clinical practice. Theoretically, the subgingival contours of the crown/abutment complex should mimic the morphology of the root and the cervical third of the anatomic crown as much and as often as possible. However, this is highly dependent upon the three-dimensional spatial position of the implant relative to the hard and soft tissue complex, in addition to the location of the definitive restoration. Frequently, a convex critical contour is required on the facial aspect of a palatally or incisally positioned implant to support an adequate gingival-margin architecture. Conversely, if the implant is placed too far facially, then a flat or concave contour is recommended. In instances where soft tissue support is not needed, the subcritical area may be undercontoured to increase the thickness, height, and stability of the soft tissue cuff.

Purpose: This pilot study evaluated and compared the degree of new bone formation following maxillary sinus graft using three different bone graft materials. Materials and Methods: Patients with an edentulous posterior maxilla (unilateral or bilateral) were included in this study and underwent a two-stage procedure. Each sinus was randomly assigned one of the three graft materials: anorganic bovine bone mineral (ABBM), anorganic equine bone mineral (AEBM), or mineralized cancellous bone allograft (MCBA). Bone core samples were obtained from the lateral wall of the grafted sites at least 8 months after maxillary sinus graft. Bone quality was evaluated during bone core retrieval. The samples were histomorphometrically analyzed using Kruskal-Wallis and Dunn-Bonferroni tests at the significance level of α = .05. Results: A total of 28 sinuses (14 unilateral and 7 bilateral) from 21 subjects, with a mean age of 61.5 (range: 33 to 75) years, were included in the study. Twenty-eight bone cores (ABBM [n = 9], AEBM [n = 9], and MCBA [n = 10]) were obtained at a mean healing time of 9.1 (range: 8 to 12) months. Six maxillary sinus membrane perforations (≤ 5 mm) were noted and repaired during surgery (21.4%). Histomorphometric analysis of the harvested bone cores revealed statistically significant differences in the percentage of vital bone, residual bone materials, and connective tissue/marrow among the different graft materials (Kruskal-Wallis; P .05). The percentage of vital bone in the MCBA group (32.0% ± 12.4%) was significantly greater than those in the ABBM (10.9% ± 8.9%) and AEBM (9.1% ± 5.9%) groups (P .05). The percentage of residual bone materials in the MCBA group (5.5% ± 5.7%) was, however, significantly less than those in the ABBM (34.3% ± 12.1%) and AEBM (38.9% ± 5.3%) groups (P .05). There were no significant differences in the percentage of vital bone and residual bone materials between ABBM and AEBM (P = 1.0). Newly formed bone and residual graft materials were integrated into the surrounding tissue with no sign of inflammation or foreign-body reaction. Conclusion: Within the confines of the study, MCBA has significantly greater new bone formation than ABBM and AEBM. AEBM showed comparable histomorphometric results in all parameters (percentage of vital bone, residual bone materials, and connective tissue/marrow) to ABBM. Schlagwörter: bone formation, bone graft materials, histomorphometric analysis, maxillary sinus graft