Guided Bone Regeneration using Titanium Mesh to Augment 3-dimensional alveolar defects prior to implant placement. A Pilot Study

Regenerative approaches in alveolar bone augmentation for dental implant placement: Techniques, biomaterials, and clinical decision-making: A comprehensive review

OBJECTIVES

This review aimed to evaluate the outcomes of ridge augmentation techniques and bio-materials for alveolar bone regeneration, addressing inconsistencies across studies. A decision tree is provided to guide clinicians in selecting optimal approaches for diverse clinical scenarios.

DATA AND SOURCES

An extensive search was conducted across electronic databases, including PubMed, Scopus, and Embase, alongside dental implant and prosthodontics journal portals. Reference lists of relevant articles were also manually reviewed up to October 2024.

STUDY SELECTION

Inclusion criteria were established to emphasize English-language human clinical trials investigating regenerative techniques and materials utilized for ridge augmentation prior to implant placement.

CONCLUSIONS

Selecting defect-specific regenerative approaches is crucial for successful outcomes in alveolar bone augmentation. While autografts remain the gold standard, advancements in allografts, xenografts, synthetics, and biological enhancers are transforming the field. Distraction osteogenesis is also gaining prominence as a promising technique. Clinicians should leverage these innovations to tailor treatments to individual patient needs for optimal results. The decision tree developed categorizes alveolar bone defects and suggests tailored approaches based on anticipated resorption patterns.

CLINICAL SIGNIFICANCE

Careful patient evaluation and tailored technique selection, combined with advancements in biomaterials and tissue engineering, are essential for achieving optimal outcomes in ridge augmentation, particularly for challenging vertical defects.

Efficacy of Bioresorbable Mesh Sheets Made of 85:15 Poly(lactic-co-glycolic acid) in the Anterior Maxilla for Alveolar Bone Augmentation

This study evaluated the efficacy of poly(lactic-co-glycolic acid) (PLGA) mesh sheets for alveolar bone reconstruction in the anterior maxilla with significant bone defects. This prospective case series included 4 male patients (mean age, 34.5 years; range, 20-49 years) with anterior maxillary bone defects. Bone augmentation was performed using a staged guided bone regeneration technique with PLGA mesh sheets as barrier membranes and a 1:1 mixture of autogenous and xenogeneic bone as grafting material. The effectiveness of bone augmentation was evaluated using preoperative and postoperative computerized tomography data at 1 and 6 months. Secondary outcomes included complications such as wound infection and dehiscence. The treatment of the 4 patients required 7 PLGA mesh sheets and particulate bone, followed by 9 implant placements. Wound healing was uneventful except for 1, wherein wound dehiscence and graft loss were observed. One patient had an exposed PLGA mesh sheet during healing, necessitating its removal. The mean vertical bone gain was 2.3 ± 0.5 mm, and the mean horizontal gain was 3.7 ± 1.3 mm at 1 month postoperatively. Sites without wound dehiscence exhibited a bone decrease rate of 6.5%-21.1%, whereas successful bone height and width increases were observed across treated sites. Bone augmentation using PLGA mesh sheets proved effective in reconstructing horizontal and vertical alveolar bone dimensions. This technique provides adequate support for implant placement, demonstrating its potential utility in cases of substantial alveolar bone deficiency.

Finite Element Analysis of Functionally Loaded Subperiosteal Implants Evaluated on a Realistic Model Reproducing Severe Atrophic Jaws

Implant-supported prosthetic rehabilitation for patients with severely atrophic jaws is challenging due to complex anatomical considerations and the limitations of conventional augmentation techniques. This study explores the potential of subperiosteal (juxta-osseous) implants as an alternative solution, using finite element analysis (FEA) to evaluate mechanical performance. Realistic jaw models, developed from radiographic data, are utilized to simulate various implant configurations and load scenarios. Results indicate that different screw placements, implant designs, and structural modifications can significantly influence stress distribution and biomechanical behavior. Upper and lower jaw models were assessed under multiple load conditions to determine optimal configurations. Findings suggest that strategic adjustments, such as adding posterior screws or altering implant connections, can enhance load distribution and reduce stress concentration, particularly in critical areas. Tensile loads in critical bone areas near cortical fixing screws exceeded 50 MPa under anterior loading, while configurations with larger load distributions reduced stress on both implant and bone. The study provides evidence-based insights into optimizing subperiosteal implant design to improve stability, longevity, and patient outcomes.

Complication, vertical bone gain, volumetric changes after vertical ridge augmentation using customized reinforced PTFE mesh or Ti-mesh. A non-inferiority randomized clinical trial

OBJECTIVE

The aim of this non-inferiority randomized clinical trial was to compare the surgical and healing complications, vertical bone gain, and volumetric bone changes after vertical ridge augmentation using two different approaches: customized Ti-reinforced d-PTFE mesh versus customized CAD/CAM Ti-mesh.

MATERIALS AND METHODS

Fifty patients with vertical bone defects were randomly treated with Ti-reinforced d-PTFE mesh (control group) or CAD/CAM Ti-mesh (test group) and a mix of autogenous bone and deproteinized bovine bone matrix. Surgical and healing complication rates (SCR-HCR), vertical bone gain (VBG), regenerated bone volume (RBV), and regeneration rates (RR and ERR) were recorded and analysed [significance level (α) of 0.05].

RESULTS

Of the 50 patients, 48 underwent bone augmentation surgery. SCR were 4% and 12% in PTFE and Ti-mesh, whereas HCR were 12.5% and 8.3%. VBG were 5.79 ± 1.71 mm (range: 3.2-8.8 mm) in the PTFE group and 5.18 ± 1.61 mm (range: 3.1-8.0 mm) in the Ti-mesh group (p = .233), whereas RBV were 1.46 ± 0.48 cc and 1.26 ± 0.55. RR was 99.5% and 87.0%, demonstrating a statistically significant difference (p = .013). Finally, the values related to pseudo-periosteum, bone density, and implant stability were similar in the two study groups. Osseointegration rates were 98.2% and 98.3%.

CONCLUSIONS

This study confirmed the non-inferiority of customized CAD/CAM titanium meshes with respect to reinforced PTFE meshes in terms of surgical and healing complications. Although PTFE meshes showed higher vertical bone gain and regeneration rates than Ti-meshes, no significant differences were found.

Alveolar bone regeneration using a 3D-printed patient-specific resorbable scaffold for dental implant placement: A case report

BACKGROUND

This case report demonstrates the effective clinical application of a 3D-printed, patient-specific polycaprolactone (PCL) resorbable scaffold for staged alveolar bone augmentation.

OBJECTIVE

To evaluate the effectiveness of a 3D-printed PCL scaffold in facilitating alveolar bone regeneration and subsequent dental implant placement.

MATERIALS AND METHODS

A 46-year-old man with a missing tooth (11) underwent staged alveolar bone augmentation using a patient-specific PCL scaffold. Volumetric bone gain and implant stability were assessed. Histological analysis was conducted to evaluate new bone formation and graft integration.

RESULTS

The novel approach resulted in a volumetric bone gain of 364.69 ± 2.53 mm3, sufficient to reconstruct the original alveolar bone contour and permit dental implant placement. Histological analysis showed new bone presence and successful graft integration across all defect zones (coronal, medial, and apical), with continuous new bone formation around and between graft particles. The dental implant achieved primary stability at 35 Ncm-1, indicating the scaffold's effectiveness in promoting bone regeneration and supporting implant therapy. The post-grafting planned implant position deviated overall by 2.4° compared with the initial restoratively driven implant plan pre-bone augmentation surgery. The patient reported low average daily pain during the first 48 h and no pain from Day 3.

CONCLUSIONS

This proof-of-concept underscores the potential of 3D-printed scaffolds in personalized dental reconstruction and alveolar bone regeneration. It marks a significant step forward in integrating additive manufacturing technologies into clinical practice through a scaffold-guided bone regeneration (SGBR) approach. The trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000118707p).

Assessment of the application of a novel three-dimension printing individualized titanium mesh in alveolar bone augmentation: A retrospective study

OBJECTIVE

To assess the clinical and radiographic outcomes of alveolar ridge augmentation using a novel three-dimensional printed individualized titanium mesh (3D-PITM) for guided bone regeneration (GBR).

MATERIALS AND METHODS

Preoperative cone-beam computed tomography (CBCT) was used to evaluate alveolar ridge defects, followed by augmentation with high-porosity 3D-PITM featuring circular and spindle-shaped pores. Postoperative CBCT scans were taken immediately and after 6 months of healing. These scans were compared with preoperative scans to calculate changes in bone volume, height, and width, along with the corresponding resorption rates. A statistical analysis of the results was then conducted.

RESULTS

A total of 21 patients participated in the study, involving alveolar ridge augmentation at 38 implant sites. After 6 months of healing, the average bone augmentation volume of 21 patients remained at 489.71 ± 252.53 mm3, with a resorption rate of 16.05% ± 8.07%. For 38 implant sites, the average vertical bone increment was 3.63 ± 2.29 mm, with a resorption rate of 17.55% ± 15.10%. The horizontal bone increment at the designed implant platform was 4.43 ± 1.85 mm, with a resorption rate of 25.26% ± 15.73%. The horizontal bone increment 2 mm below the platform was 5.50 ± 2.48 mm, with a resorption rate of 16.03% ± 9.57%. The main complication was exposure to 3D-PITM, which occurred at a rate of 15.79%.

CONCLUSION

The novel 3D-PITM used in GBR resulted in predictable bone augmentation. Moderate over-augmentation in the design, proper soft tissue management, and rigorous follow-ups are beneficial for reducing the graft resorption and the incidence of exposure.

Customized 3D-Printed Mesh, Membrane, Bone Substitute, and Dental Implant Applied to Guided Bone Regeneration in Oral Implantology: A Narrative Review

Background: The new frontiers of computer-based surgery, technology, and material advances, have allowed for customized 3D printed manufacturing to become widespread in guided bone regeneration (GBR) in oral implantology. The shape, structural, mechanical, and biological manufacturing characteristics achieved through 3D printing technologies allow for the customization of implant-prosthetic rehabilitations and GBR procedures according to patient-specific needs, reducing complications and surgery time. Therefore, the present narrative review aims to elucidate the 3D-printing digital radiographic process, materials, indications, 3D printed manufacturing-controlled characteristics, histological findings, complications, patient-reported outcomes, and short- and long-term clinical considerations of customized 3D printed mesh, membranes, bone substitutes, and dental implants applied to GBR in oral implantology. Methods: An electronic search was performed through MEDLINE/PubMed, Scopus, BioMed Central, and Web of Science until 30 June 2024. Results: Three-dimensionally printed titanium meshes and bone substitutes registered successful outcomes in vertical/horizontal bone defect regeneration. Three-dimensionally printed polymeric membranes could link the advantages of conventional resorbable and non-resorbable membranes. Few data on customized 3D printed dental implants and abutments are available, but in vitro and animal studies have shown new promising designs that could improve their mechanical properties and tribocorrosion-associated complications. Conclusions: While 3D printing technology has demonstrated potential in GBR, additional human studies are needed to evaluate the short- and long-term follow-up of peri-implant bone levels and volumes following prosthetic functional loading.

Three-dimensional imaging analysis of CAD/CAM custom-milled versus prefabricated allogeneic block remodelling at 6 months and long-term follow-up of dental implants: A retrospective cohort study

AIM

This retrospective cohort study aimed to volumetrically investigate the bone stability rate of prefabricated allogeneic bone blocks (PBB) and computer-aided design (CAD)/computer-aided manufacturing (CAM) custom-milled allogeneic bone blocks (CCBB) for ridge augmentation.

MATERIALS AND METHODS

Nineteen patients were treated with 20 allografts: 11 CCBB, 9 PBB; 10 in the maxilla and 10 in the mandible. Clinical treatment history and cone beam computed tomography scans before surgery (t0), directly after graft surgery (t1) and after 6 months of healing prior to implant insertion (t2) were evaluated using a three-dimensional evaluation software for absolute bone volume, stability as well as vertical and horizontal bone gain. Furthermore, the inserted implants were analysed for survival, marginal bone loss (MBL) and complications for a mean follow-up period of 43.75 (±33.94) months.

RESULTS

A mean absolute volume of 2228.1 mm3 (±1205) was grafted at t1. The bone stability rate was 87.6% (±9.9) for CCBB and 83.0% (±14.5) for PBB. The stability was higher in the maxilla (91.6%) than in the mandible (79.53%). Surgery time of PBB was longer than for CCBB (mean Δ = 52 min). The survival rate of the inserted implants was 100% with a mean MBL of 0.41 mm (±0.37).

CONCLUSION

The clinical performance of both allograft block designs was equally satisfactory for vertical and horizontal bone grafting prior to implant placement.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT06027710.

Digital planning and bone regenerative technologies: A narrative review

OBJECTIVES

The aim of this narrative review was to explore the application of digital technologies (DT) for the simplification and improvement of bone augmentation procedures in advanced implant dentistry.

MATERIAL AND METHODS

A search on electronic databases was performed to identify systematic reviews, meta-analyses, randomized and non-randomized controlled trials, prospective/retrospective case series, and case reports related to the application of DT in advanced implant dentistry.

RESULTS

Seventy-nine articles were included. Potential fields of application of DT are the following: 1) the use of intra-oral scanners for the definition of soft tissue profile and the residual dentition; 2) the use of dental lab CAD (computer-aided design) software to create a digital wax-up replicating the ideal ridge and tooth morphology; 3) the matching of STL (Standard Triangulation Language) files with DICOM (DIgital COmmunication in Medicine) files from CBCTs with a dedicated software; 4) the production of stereolithographic 3D models reproducing the jaws and the bone defects; 5) the creation of surgical templates to guide implant placement and augmentation procedures; 6) the production of customized meshes for bone regeneration; and 7) the use of static or dynamic computer-aided implant placement.

CONCLUSIONS

Results from this narrative review seem to demonstrate that the use of a partially or fully digital workflow can be successfully used also in advanced implant dentistry. However, the number of studies (in particular RCTs) focused on the use of a fully digital workflow in advanced implant dentistry is still limited and more studies are needed to properly evaluate the potentials of DT.

Hard tissue stability outside the buccal bone arch contour after guided bone regeneration in the anterior maxilla: A retrospective cohort radiographic study

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.

Clinical Study of 14 Cases of Bone Augmentation with Selective Laser Melting Titanium Mesh Plates

Additive manufacturing techniques are being used in the medical field. Orthopedic hip prostheses and denture bases are designed and fabricated based on the patient's computer-aided design (CAD) data. We attempted to incorporate this technique into dental implant bone augmentation. Surgical simulation was performed using patient data. Fourteen patients underwent bone augmentation using a selective laser melting (SLM) titanium mesh plate. The results showed no evidence of infection in any of the 14 patients. In 12 patients, only one fixation screw was used, and good results were obtained. The SLM titanium mesh plate was good adaptation in all cases, with bone occupancy greater than 90%. The average bone resorption of the marginal alveolar bone from the time of dental implant placement to the time of the superstructure placement was 0.69 ± 0.25 mm. Implant superstructures were placed in all cases, and bone augmentation with SLM titanium mesh plates was considered a useful technique.

3D printing for bone regeneration: challenges and opportunities for achieving predictability

3D printing offers attractive opportunities for large-volume bone regeneration in the oro-dental and craniofacial regions. This is enabled by the development of CAD-CAM technologies that support the design and manufacturing of anatomically accurate meshes and scaffolds. This review describes the main 3D-printing technologies utilized for the fabrication of these patient-matched devices, and reports on their pre-clinical and clinical performance including the occurrence of complications for vertical bone augmentation and craniofacial applications. Furthermore, the regulatory pathway for approval of these devices is discussed, highlighting the main hurdles and obstacles. Finally, the review elaborates on a variety of strategies for increasing bone regeneration capacity and explores the future of 4D bioprinting and biodegradable metal 3D printing.

Bone reconstruction of extensive maxillomandibular defects in adults

Reconstruction of significant maxillomandibular defects is a challenge that has been much discussed over the last few decades. Fundamental principles were developed decades ago (bone bed viability, graft immobilization). Clinical decision-making criteria are highly relevant, including local/systemic factors and incision designs, the choice of material, grafting technique, and donor site morbidity. Stabilizing particulated grafts for defined defects-that is, via meshes or shells-might allow significant horizontal and vertical augmentation; the alternatives are onlay and inlay techniques. More significant defects might require extra orally harvested autologous bone blocks. The anterior iliac crest is often used for nonvascularized augmentation, whereas more extensive defects often require microvascular reconstruction. In those cases, the free fibula flap has become the standard of care. The development of alternatives is still ongoing (i.e., alloplastic reconstruction, zygomatic implants, obturators, distraction osteogenesis). Especially for these complex procedures, three-dimensional planning tools enable facilitated planning and a surgical workflow.

Full-Digital Customized Meshes in Guided Bone Regeneration Procedures: A Scoping Review

Meshes, especially titanium ones, are being widely applied in oral surgery. In guided bone regeneration (GBR) procedures, their use is often paired with membranes, being resorbable or non-resorbable. However, they present some limitations, such as difficulty in the treatment of severe bone defects, alongside frequent mesh exposure. Customized meshes, produced by a full-digital process, have been recently introduced in GBR procedures. Therefore, the focus of the present review is to describe the main findings in recent years of clinical trials regarding patient-specific mesh produced by CAD/CAM and 3D printing workflow, made in titanium or even PEEK, applied to GBR surgeries. The purpose is to analyze their clinical management, advantages, and complications. This scoping review considered randomized clinical trials, observational studies, cohort studies, and case series/case reports studies. Studies that did not meet inclusion criteria were excluded. The preferred reporting items for scoping reviews (PRISMA-ScR) consensus was followed. A total of 15 studies were selected for this review. Based on the studies included, the literature suggests that meshes produced by a digital process are used to restore complex and severe bone defects. Moreover, they give satisfactory aesthetic results and fit the defects, counteracting grid exposure. However, more clinical trials should be conducted to evaluate long-term results, the rate of complications, and new materials for mesh manufacturing.

The effect of bone defect size on the 3D accuracy of alveolar bone augmentation performed with additively manufactured patient-specific titanium mesh

OBJECTIVE

Additively manufactured (3D-printed) titanium meshes have been adopted in the dental field as non-resorbable membranes for guided bone regeneration (GBR) surgery. However, according to previous studies, inaccuracies between planned and created bone volume and contour are common, and many reasons have been speculated to affect its accuracy. The size of the alveolar bone defect can significantly increase patient-specific titanium mesh design and surgical difficulty. Therefore, this study aimed to analyze and investigate the effect of bone defect size on the 3D accuracy of alveolar bone augmentation performed with additively manufactured patient-specific titanium meshes.

METHODS

Twenty 3D-printed patient-specific titanium mesh GBR surgery cases were enrolled, in which 10 cases were minor bone defect/augmentation (the planned bone augmentation surface area is less than or equal to 150 mm² or one tooth missing or two adjacent front-teeth/premolars missing) and another 10 cases were significant bone defect/augmentation (the planned bone augmentation surface area is greater than 150 mm² or missing adjacent teeth are more than two (i.e. ≥ three teeth) or missing adjacent molars are ≥ two teeth). 3D digital reconstruction/superposition technology was employed to investigate the bone augmentation accuracy of 3D-printed patient-specific titanium meshes.

RESULTS

There was no significant difference in the 3D deviation distance of bone augmentation between the minor bone defect/augmentation group and the major one. The contour lines of planned-CAD models in two groups were basically consistent with the contour lines after GBR surgery, and both covered the preoperative contour lines. Moreover, the exposure rate of titanium mesh in the minor bone defect/augmentation group was slightly lower than the major one.

CONCLUSION

It can be concluded that the size of the bone defect has no significant effect on the 3D accuracy of alveolar bone augmentation performed with the additively manufactured patient-specific titanium mesh.

Customized Barrier Membrane (Titanium Alloy, Poly Ether-Ether Ketone and Unsintered Hydroxyapatite/Poly-l-Lactide) for Guided Bone Regeneration

Sufficient bone volume is indispensable to achieve functional and aesthetic results in the fields of oral oncology, trauma, and implantology. Currently, guided bone regeneration (GBR) is widely used in reconstructing the alveolar ridge and repairing bone defects owing to its low technical sensitivity and considerable osteogenic effect. However, traditional barrier membranes such as collagen membranes or commercial titanium mesh cannot meet clinical requirements, such as lack of space-preserving ability, or may lead to more complications. With the development of digitalization and three-dimensional printing technology, the above problems can be addressed by employing customized barrier membranes to achieve space maintenance, precise predictability of bone graft, and optimization of patient-specific strategies. The article reviews the processes and advantages of three-dimensional computer-assisted surgery with GBR in maxillofacial reconstruction and alveolar bone augmentation; the properties of materials used in fabricating customized bone regeneration sheets; the promising bone regeneration potency of customized barrier membranes in clinical applications; and up-to-date achievements. This review aims to present a reference on the clinical aspects and future applications of customized barrier membranes.