Changes in soft tissue dimensions following horizontal guided bone regeneration with a split-thickness flap design - evaluation of 8 cases with a digital method.

BACKGROUND: Peri-implant soft tissue corrections are often indicated following alveolar ridge augmentation, due to the distortion of the keratinized mucosa at the area of augmentation. The objective of the current study was to evaluate the dimensional soft tissue changes following horizontal guided bone regeneration (GBR) utilizing 3D digital data. METHODS: 8 mandibular surgical sites with horizontal alveolar ridge deficiencies were treated utilizing a resorbable collagen membrane and a split-thickness flap design. Baseline and 6-month follow-up cone-beam computed tomography (CBCT) scans were reconstructed as 3D virtual models and were superimposed with the corresponding intraoral scan. Linear changes of supracrestal vertical- horizontal soft tissue alterations were measured in relation to the alveolar crest at the mesial- middle- and distal aspect of the surgical area. Soft tissue dimensions were measured at baseline and at 6-month follow-up. RESULTS: Preoperative supracrestal soft tissue height measured midcrestally averaged at 2.37 mm ± 0.68 mm, 2.37 mm ± 0.71 mm and 2.64 mm ± 0.87 mm at the mesial-, middle- and distal planes. Whereas postoperative supracrestal soft tissue height was measured at 2.62 mm ± 0.72 mm, 2.67 mm ± 0.67 mm and 3.69 mm ± 1.02 mm at the mesial, middle and distal planes, respectively. Supracrestal soft tissue width changed from 2.14 mm ± 0.72 mm to 2.47 mm ± 0.46 mm at the mesial, from 1.72 mm ± 0.44 mm to 2.07 mm ± 0.67 mm and from 2.15 mm ± 0.36 mm to 2.36 mm ± 0.59 mm at the mesial, middle and distal planes, respectively. Additionally the buccal horizontal displacement of supracrestal soft tissues could be observed. CONCLUSIONS: The current study did not report significant supracrestal soft tissue reduction following horizontal GBR with a split-thickness flap. Even though there was a slight increase in both vertical and horizontal dimensions, differences are clinically negligible. TRAIL REGISTRATION: The trail was approved by the U.S. National Library of Medicine ( www. CLINICALTRIALS: gov ); trial registration number: NCT05538715; registration date: 09/09/2022.

Novel Technique to Reconstruct Peri-Implant Keratinised Mucosa Width Using Xenogeneic Dermal Matrix. Clinical Case Series.

Reconstruction of sufficient buccal peri-implant keratinised mucosa width (PIKM-W) is reported to reduce the symptoms of peri-implantitis. In order to reduce the drawbacks of autogenous graft harvesting, we investigated a novel porcine dermal matrix (XDM, mucoderm®) using a modified surgical technique for augmentation of PIKM-W. Twenty-four patients were recruited with insufficient (<2 mm) PIKM-W. After split thickness flap preparation, the XDM was trimmed, rehydrated and tightly attached to the recipient periosteal bed using modified internal/external horizontal periosteal mattress sutures via secondary wound healing. Change of the PIKM-W and dimension of the graft remodelling were evaluated at 6 and 12 months postoperatively. The mean PIKM-W changed from 0.42 ± 0.47 to 3.17 ± 1.21 mm at 6 M and to 2.36 ± 1.34 mm at 12 M in the maxilla and from 0.29 ± 0.45 mm to 1.58 ± 1.44 mm at 6 M and to 1.08 ± 1.07 mm at 12 M in the mandible. Graft dimensions decreased by 67.7 ± 11.8% and 81.6 ± 16.6% at 6 M, and continued to 75.9 ± 13.9% and 87.4 ± 12.3% at 12 M, in the maxilla and mandible, respectively. Clinical parameters showed statistically significant intra- and intergroup differences between the baseline and 6 and 12 months (p < 0.05). The present technique using the XDM was safe and successfully reconstructed PIKM-W in both arches. The XDM alone seems to be a suitable alternative to autograft for PIKM-W augmentation in the maxilla.

The role of 3D technology in the practical education of congenital coarctation and its treatment-a feasibility pilot study.

BACKGROUND: Coarctation of the aorta (CoA) is a congenital disease with an incidence of 4 out of 10,000 live births, therefore proper education of its treatment is essential. Understanding the disease and the wide array of treatment options is often difficult. Additive manufacturing technology can be used to produce 3D printed hands-on surgical training tools (HOSTT), which can be used for the education and practical training of CoA. This study aimed to investigate the effectiveness of a 3D printable HOSTT for the simulation of coarctation surgery, and it' possible role in practical education. METHODS: Participants were medical students of Semmelweis University between the second and sixth academic year. A virtual 3D model of an aorta with CoA was generated from a computed tomography angiography scan. Each participant received a 3D-printed aorta phantom and performed either one of four surgical treatment modalities. The simulated surgeries included end-to-end anastomosis, end-to-side anastomosis, prosthetic patch, and subclavian flap aortoplasty. Participants provided feedback, evaluating their understanding of the disease and its treatment by the four surgical reconstruction modalities on a seven-point Likert scale before and after the sessions. RESULTS: 21 medical students participated in this study. Participants' average rating of their understanding of CoA disease and it treatment options before practical training was 4.62 ± 1.07. After training, their average rating increased to 6.19 ± 1.08, showing statistically significant difference. CONCLUSIONS: Within this study's limitations, the applied HOSTT, manufactured using 3D printing, was effective for the practical training of CoA's surgical treatment methods for medical students.

Mechanical Performance of Extensive Restorations Made with Short Fiber-Reinforced Composites without Coverage: A Systematic Review of In Vitro Studies.

In recent years, composite resin materials have been the most frequently used materials for direct restorations of posterior teeth. These materials have some clinically relevant limitations due to their lack of fracture toughness, especially when used in larger cavities with high volume factors or when utilized as direct or indirect overlays or crown restorations. Recently, short-fiber-reinforced composite materials have been used in bi-structure restorations as a dentine substituting material due to their superior mechanical properties; however, there is no scientific consensus as to whether they can be used as full restorations. The aim of our review was to examine the available literature and gather scientific evidence on this matter. Two independent authors performed a thorough literature search using PubMed and ScienceDirect up until December 2023. This study followed the PRISMA guidelines, and the risk of bias was assessed using the QUIN tool. The authors selected in vitro studies that used short-fiber-reinforced composite materials as complete restorations, with a conventional composite material as a comparison group. Out of 2079 potentially relevant articles, 16 met our inclusion criteria. All of the included studies reported that the usage of short-fiber-reinforced composites improved the restoration's load-bearing capacity. Fifteen of the included publications examined the fracture pattern, and thirteen of them reported a more favorable fracture outcome for the short-fiber-reinforced group. Only one article reported a more favorable fracture pattern for the control group; however, the difference between groups was not significant. Within the limitations of this review, the evidence suggests that short-fiber-reinforced composites can be used effectively as complete restorations to reinforce structurally compromised teeth.

Alveolar cleft reconstruction utilizing a particulate autogenous tooth graft and a novel split-thickness papilla curtain flap - A retrospective study.

During secondary alveolar cleft grafting, the use of autogenous cancellous bone harvested from the iliac crest is still considered the gold standard. Due to the risk of donor-site morbidity and excessive graft resorption, alternative grafting materials (e.g. intraoral bone, xenografts) have been tested. Autogenous tooth bone graft (ATB) is a novel material derived from extracted teeth. ATB has successfully been used in pre-prosthetic and periodontal surgery for hard-tissue reconstruction. Seven patients with unilateral cleft lip and palate were treated with ATB, using their own deciduous teeth for grafting. Defects were accessed utilizing a novel split-thickness papilla curtain flap. Cone-beam computed tomography scans were taken prior to and 3 months following cleft surgery to assess graft integration, graft stability, and the volume of the newly formed hard tissues. Hard-tissue gain, as measured at the 3-month follow-up, averaged 0.65 cm3 ± 0.26 cm3. Results showed acceptable graft integration and stability at the 3-month follow-up, with no adverse effects or excessive resorption of the graft. The use of ATB might be a feasible alternative for alveolar cleft grafting. However, long-term studies using a large sample size are required to derive further conclusions.

Possible Applications for a Biodegradable Magnesium Membrane in Alveolar Ridge Augmentation-Retrospective Case Report with Two Years of Follow-Up.

Background and Objectives: A rigid, resorbable magnesium membrane was recently developed, combining the advantages of resorbable and non-resorbable membranes. Our aim was to describe the application of this membrane for guided bone regeneration (GBR). Materials and Methods: This case report described the treatment and 3D evaluation of two cases utilizing a resorbable magnesium barrier membrane. In Case #1, GBR was performed with a bilayer tunnel flap. The magnesium barrier was placed fixed subperiosteally through remote vertical incisions. In Case #2, GBR was performed using a split-thickness flap design. Volumetric and linear hard tissue alterations were assessed by 3D cone-beam computed tomography subtraction analysis, as well as with conventional intraoral radiography. Results: Case #1 showed a volumetric hard tissue gain of 0.12 cm3, whereas Case #2 presented a 0.36 cm3 hard tissue gain. No marginal peri-implant hard tissue loss could be detected at the two-year follow-up. Conclusions: The application of conventional resorbable collagen membranes would be difficult in either of the cases presented. However, the rigid structure of the magnesium membrane allowed for the limitations of conventional resorbable membranes to be overcome.

[The role of 3D technology in the support of mechanical circulation therapy.] / A 3D technológia szerepe a muszívterápiában.

INTRODUCTION: Successful mechanical circulatory support is influenced by various factors, which are difficult or impossible to control. For ideal functioning of the left ventricular assist device inflow-cannula, its axis should be close to parallel with the septum, facing the mitral valve within the left ventricle. Numerous international publications discuss that deviation from optimal implantation can lead to inadequate functioning and serious complications. OBJECTIVE: Our objective was to developing a method, which, using 3D technology, anatomical and hydrodynamic data, makes optimal surgical implantation of the left ventricular assist device possible. METHOD: Data of 57 patients, receiving mechanical circulatory support at Semmelweis University, Heart and Vascular Center, were analyzed retrospectively. Results of operations performed with the patented novel navigation device (exoskeleton) were compared with results of operations performed conventionally, without navigation (control group). Following pairing based on estimated participation probability, postoperative data of 7-7 patients were compared. DICOM files from CT angiography images were used to create virtual geometries of individual hearts. Optimal inflow-cannula angle was determined through hydrodynamic simulation. Exoskeletons were printed using synthetic resin suitable for surgical purposes. Exoskeleton templates guided punch knife positioning and inflow-cannula implantation. RESULTS: Evaluation of postoperative CT angiography images showed that the angle between inflow-cannula and interventricular septum significantly differed in the exoskeleton and control groups (10.13° ± 2.69° vs. 22.87° ± 12.38°, p = 0.0208). Hydrodynamic tests found significantly lower turbulence in the exoskeleton group. Simulated turbulent kinetic energy was significantly lower in the exoskeleton group, which was 11.7 m2/s2 ± 9.39 m2/s2 vs. 49.59 m2/s2 ± 7.61 m2/s2 on average. CONCLUSION: The results suggest left ventricular assist device implantation with patented exoskeleton to be a standardizable, safe and effective method. Preliminary results suggest, that the method may facilitate individualized care, reduce surgical time and incidence of serious complications. Orv Hetil. 2023; 164(26): 1026-1033.

Efficacy and volume stability of a customized allogeneic bone block for the reconstruction of advanced alveolar ridge deficiencies at the anterior maxillary region: a retrospective radiographic evaluation.

OBJECTIVES: The aim of this retrospective case series was to evaluate the efficacy and volume stability of a customized allogeneic bone block (CABB) for the hard tissue reconstruction of severely atrophied anterior maxillary ridges. MATERIALS AND METHODS: Hard tissue alterations between baseline (T1), 2-month follow-up (T2), and 6-month follow-up (T3) cone-beam computed tomography scans were evaluated with semi-automatic segmentation. Following automatic spatial alignment of the datasets, 3D subtraction analysis was performed. The volume stability of the inserted allogeneic bone block was determined on the basis of the ratio of the T3 and T2 hard tissue volumes. RESULTS: The newly formed hard tissue volume at T2 averaged at of 0.75 cm3 ± 0.57 cm3, whereas at T3, an average of 0.52 cm3 ± 0.42 cm3 volumetric hard tissue gain could be detected. The T3/T2 ratio was found to be 67.83% ± 18.72% on average. The dice similarity coefficient between the T2 and T3 hard tissue models averaged at 0.73 ± 0.15. CONCLUSIONS: Cancellous CABBs are a reliable option for the reconstruction of severely atrophied alveolar ridges. The resorption rates of these grafts are similar to those found in the literature; however, with precise manufacturing and proper intraoperative flap management, the resorption rates may be reduced. CLINICAL RELEVANCE: With precise knowledge of the resorption patterns, the shape of blocks can be altered in the future to compensate for the volumetric loss.

Presentation of a novel surgical technique in periodontally accelerated osteogenic orthodontics. CBCT assessment of the buccal alveolar dimensional changes: a proof-of-concept report of four cases.

OBJECTIVES: The aim of this report was to present the effectiveness of a novel augmented corticotomy performed before orthodontic treatments in the prevention of buccal alveolar dehiscence and gingival recession. METHOD AND MATERIALS: Four periodontally healthy individuals presenting crowding and thin bone morphotype in the mandibular anterior area were treated with a double-layer tunnel flap, piezotomy, and hard and soft-tissue augmentation. Patients were divided into two groups according to the utilized graft material. The exclusive use of demineralized bovine bone minerals (group 2) was compared to the use of autologous concentrated growth factor-enriched bone graft matrix, "sticky bone" (group 1). CBCT measurements were performed before and 6 months after surgery. Orthodontic treatment was initialized 1 week after surgery. RESULTS: Postoperative wound healing was uneventful, and tooth alignments were successful in all cases. Postoperative buccal hard tissue dimensions were favorable in both groups, with no occurring bone dehiscence or gingival recession. The seemingly better results of group 2, in terms of quantitative hard tissue changes, did not have any clinical significance according to the objective to be achieved. In contrast, qualitative radiographic analysis showed a more homogenous tissue formation around teeth in group 1. CONCLUSION: It can be concluded that the presented preorthodontic treatment approach seems to be successful in preventing alveolar dehiscence and gingival recession around buccally inclined mandibular anterior teeth.