Graft Material Research Articles

Does the outcome of graft materials at dental implant sites differ between patients with normal and compromised bone health?

To assess the outcome of bone graft material at alveolar bone augmentation sites combined with dental implants in postmenopausal women with compromised bone health by evaluating cone beam computed tomography (CBCT) scans at multiple time points. CBCT scans were analyzed on 55 postmenopausal women with compromised bone health status to determine the fate of alveolar bone augmentation. CBCT scans were taken immediately after surgery and 9 and 24 months post-operatively. The patient's medication regimens and durations were recorded, and the pixel intensity value (PIV) was measured and standardized using scoring criteria and visual assessment. Statistical analyses included two-sample t-tests for continuous variables and Fisher's exact tests for categorical variables. Among the normal patients, 73% received a grade 2 visual score, and 27% received a grade 1 visual score. After 24 months, 45% of patients received a grade 2 score, and 27% received a grade 3 score. In the osteoporotic group receiving medication, 77% of participants received a grade 1 visual score at the 9-month postoperative evaluation, while 23% received a grade 2 score. At the 24-month assessment, 55% of patients received a grade 1 score, 41% received a grade 2 score, and only 5% received a grade 3 score. Notably, although the graft material did not remodel into native bone, it was a scaffold for implants in controlled osteoporotic patients. The study's results show that the pixel intensity values of particulate graft materials are similar across the three different time points, suggesting that the graft material's pixel intensity value remains constant in postmenopausal women with osteoporosis. The study's limitations include a small sample size and a restricted 24-month follow-up period. This limited time frame may need to capture long-term changes or variations in graft materials adequately. Future research should include a larger sample size and have a longer follow-up duration to provide a more comprehensive understanding of the change in graft materials between patients with normal and compromised bone health.

Horizontal Alveolar Ridge Splitting and Expansion.

When considering placing dental implants in atrophic edentulous sites, there may be inadequate site width and little or no vertical bone loss. Any of several surgical procedures can augment these sites. Extracortical augmentation is done by applying graft material against the cortical bone. This technique expects progenitor cells to migrate outside the bony ridge's confines and form new bone. Another method entails ridge splitting and expansion to create space for osteogenesis and, when possible, implant placement. This may be a better method for horizontal ridge augmentation. The ridge is split, separating the facial and lingual cortices for a complete bone fracture. The patient's osseous cells then can migrate into the created space from the exposed medullary bone to form bone. The technique can be preferably performed flapless so the intact periosteum maintains a blood supply to ensure appropriate healing.

Alloplastic bone grafts in maxillofacial surgery – An overview

Bone grafting techniques have been used by medical practitioners for over a century. A few factors that influence how successfully a grafted material is assimilated are its mechanical strength, pore size, ability to stimulate bone growth, and type of the graft. The four properties that the bone transplant material should possess are osteogenesis, osteoinduction, osteoconduction, and osteointegration. Despite being the only material with all four qualities, autologous bone has limited applications because of morbidities at the donor site. Allogeneic bone, which is taken from a different person and is commonly processed by tissue banks, is an alternative to autogenous bone. It carries a danger of spreading illness and being antigenic. Over the past few decades, the development of synthetic bone substitutes has opened up a wide range of options and opportunities to solve these limitations. In bone grafting procedures, synthetic bone replacements and biological components are quickly taking the place of natural grafts. Considerations include the patient's characteristics, the location, the extent of the lesion, and the cost and availability of the graft materials. This review has covered a variety of commonly used alloplastic materials.

In vitro evaluation of bone cell response to novel 3D-printable nanocomposite biomaterials for bone reconstruction.

Critically-sized segmental bone defects represent significant challenges requiring grafts for reconstruction. 3D-printed synthetic bone grafts are viable alternatives to structural allografts if engineered to provide appropriate mechanical performance and osteoblast/osteoclast cell responses. Novel 3D-printable nanocomposites containing acrylated epoxidized soybean oil (AESO) or methacrylated AESO (mAESO), polyethylene glycol diacrylate, and nanohydroxyapatite (nHA) were produced using masked stereolithography. The effects of volume fraction of nHA and methacrylation of AESO on interactions of differentiated MC3T3-E1 osteoblast (dMC3T3-OB) and differentiated RAW264.7 osteoclast cells with 3D-printed nanocomposites were evaluated in vitro and compared with a control biomaterial, hydroxyapatite (HA). Higher nHA content and methacrylation significantly improved the mechanical properties. All nanocomposites supported dMC3T3-OB cells' adhesion and proliferation. Higher amounts of nHA enhanced cell adhesion and proliferation. mAESO in the nanocomposites resulted in greater adhesion, proliferation, and activity at day 7 compared with AESO nanocomposites. Excellent osteoclast-like cells survival, defined actin rings, and large multinucleated cells were only observed on the high nHA fraction (30%) mAESO nanocomposite and the HA control. Thus, mAESO-based nanocomposites containing higher amounts of nHA have better interactions with osteoblast-like and osteoclast-like cells, comparable with HA controls, making them a potential future alternative graft material for bone defect repair.

The adjunctive effect of polydeoxyribonucleotide on bone formation in alveolar ridge preservation: A pre-clinical in vivo study.

This study investigated the adjunctive effect of polydeoxyribonucleotide (PDRN) on bone formation in alveolar ridge preservation (ARP) sockets. Both mandibular second, third and fourth premolars of eight beagle dogs were randomly divided into ARP and ARP/PDRN groups. Following tooth extraction, ARP procedures were conducted using collagenized alloplastic graft material and bilayer collagen membrane soaked with normal saline (ARP group) or PDRN (ARP/PDRN group) for 10 min before application. Both groups were also randomly allocated to 2-, 4- or 12-week healing subgroups. The primary endpoint of this study was to compare histomorphometric differences between ARP and ARP/PDRN. The secondary endpoints of this study were to compare micro-CT analysis and three-dimensional volumetric measurement between the two groups. In the histomorphometric analysis, the ARP/PDRN group exhibited greater new bone formation at coronal, middle and total position compared with the ARP group at 2-week healing. The number of newly formed blood vessels was higher in the ARP/PDRN group than in the ARP group at 2- and 4-week healing. In micro-CT analysis, the mean new bone volume/total bone volume between ARP and ARP/PDRN was statistically significant at 2-week healing. Ridge volume alterations were significantly decreased in the ARP/PDRN group during entire healing time compared with the ARP group, especially on the buccal side. The application of PDRN in ARP might provide additional benefits for early bone regeneration and maintenance of buccal ridge volume.

The effect of magnesium ions synergistic with mineralized collagen on osteogenesis/angiogenesis properties by modulating macrophage polarization in vitro and in vivo

In bone tissue engineering, the bone immunomodulatory properties of biomaterials are critical for bone regeneration, which is a synergistic process involving physiological activities like immune response, osteogenesis, and angiogenesis. The effect of the macrophage immune microenvironment on the osteogenesis and angiogenesis of various material extracts was examined in this experiment using Mg2+ and Nano-hydroxyapatite/collagen (nHAC) in both a single application and a combined form. This study in vitro revealed that the two compounds combined significantly inhibited the NF-κB signaling pathway and reduced the release of inflammatory factors from macrophages when compared with the extraction phase alone. Additionally, by contributing to the polarization of macrophages towards the M2 type, the combined effects of the two materials can significantly improve osteogenesis/angiogenesis. The results of in vivo experiments confirmed that Mg2+/nHAC significantly promoted bone regeneration and angiogenesis. This study offers a promising method for enhancing bone graft material osseointegration.

Application of sticky bone combined with concentrated growth factor (CGF) for horizontal alveolar ridge augmentation of anterior teeth: a randomized controlled clinical study.

This study was designed to estimate the effect of sticky bone combined with concentrated growth factor (CGF) on anterior alveolar horizontal augmentation during implantation. Twenty-eight patients were randomly assigned to either the test group (Group 1, n = 14) or the control group (Group 2, n = 14). Patients in Group 1 and Group 2 underwent GBR using sticky bone combined with CGF and bone powders mixed with saline, respectively. On postoperative Day 7, the patients completed the visual analogue scale (VAS). Three-dimensional models of maxillary alveolar bone were reconstructed from CBCT data at different periods, and the bone volume conversion rate was calculated with the assistance of a measurement marker guide. Labial bone thickness before and after trauma closure and bone density at six months postoperatively were also measured. The mean bone volume conversion rate for Group 1 (72.09 ± 12.18%) was greater than that for Group 2 (57.47 ± 9.62%, P = 0.002). The VAS score was lower for Group 1 than for Group 2 (P = 0.032). At six months postoperatively, greater bone density was found in patients in Group 1 than in those in Group 2, although the difference was not statistically significant (P > 0.05). The change in the thickness of the labial bone graft material in Group 1 was smaller than that in Group 2 (P = 0.025). Sticky bone combined with CGF was able to achieve better bone augmentation than conventional GBR. With excellent mechanical properties and the capacity to release growth factors, sticky bone is an ideal material for bone grafting. The study was registered at the Chinese Clinical Trial Registry on 10/04/2022 (Identification number: ChiCTR2200058500).

Development of a Novel Formulation of Bioactive Glass Based Calcium Phosphate Cement for Bone Grafting

AbstractParticulate bone grafting material can travel from the implantation site and diminish the magnitude of required bone formation response and hence its effectiveness. An easily prepared moldable graft that rapidly sets rigid in situ would alleviate this problem and in this study, such an injectable bone graft material is presented. By combining calcium phosphate (CP) salts with a bioactive glass (BG) mixed with a 2.5% Na2HPO4 solution a novel BG‐based calcium phosphate cement (CPC) is produced. Immersion in Tris buffer and simulated body fluid (SBF) solutions result in the rapid generation of octacalcium phosphate (OCP) and hydroxyapatite (HA) phases – a pre‐requisite for “bioactivity”. Cement‐conditioned media does not result in any cytotoxic potential with respect to MTT activity, DNA content, or alkaline phosphatase activity with an osteoblastic cell line. Application of the cement into standardized surgical defects in the minipig mandible results in short‐term, moderate irritation at 3 and 6 weeks and complete replacement of cement with new bone at 12 weeks.

Autologous leucocyte and platelet rich in fibrin (L-PRF) – is it a competitive solution for bone augmentation in maxillary sinus lift? A 6-month radiological comparison between xenografts and L-PRF

Maxillary lateral sinus floor elevation, or external sinus lift, is a widespread surgical intervention in the dental field. Insertion of implants in the posterior region of the maxilla often requires reconstruction of the remaining native bone that has insufficient volume.
 Background and aims. Much of the research published involves using artificial products, like xenografts and resorbable collagen membranes, after a prior Cone Beam Computer Tomography (CBCT) investigation. Nowadays, more accessible access, less financial costs, a biological approach, and faster healing are objectives that surround this procedure. Leucocytes and platelets rich in Fibrin (L-PRF) are a natural component with a high concentration of growth factors. Due to its regenerative properties and lack of complications, it is used in several medical fields, like orthopedics, dermatology, and oral surgery. This retrospective study aims to compare results in bone height and volume obtained through external sinus lift, either by using xenografts or autologous plasma rich in fibrin, by evaluating the quantity of new bone formation from a radiological point of view.
 Methods. Fifty-eight Caucasian patients were included in this retrospective study; 48 were submitted to xenograft procedure, and 10 were selected for L-PRF grafting material with simultaneous implant placement. Lack of clinical and histological studies performed on patients with L-PRF surgeries limited us in choosing a larger group for the radiological analysis. CBCT evaluation was performed before surgery and 6 months after. All patients selected for the study presented good general and oral health, acute oral and sinus infections excluded; smoking and periodontal disease were also criteria of exclusion. Two operators performed the measurements in pre-established landmarks in different time frames. The two independent groups were compared with the Wilcoxon rank-sum test for quantitative data. Qualitative characteristics were described as counts and percentages. All analyses were performed in an R environment for statistical computing and graphics.
 Results. Mean bone height gain in the xenograft group in the regions was as follows: 7.44 for the anterior landmark, 12.14 for the median and 8.28 for the distal. The mean group height gained for the L-PRF group was 0.1 anteriorly, -0.18 for the median measurement, and 0.23 distally. We obtained excellent overall reliability for all the height measurements between the two operators.
 Conclusions. Further studies must be conducted to establish new sets of surgical protocols in case L-PRF alone is found to be a reliable, stable, biological alternative to the well-documented xenografts in external sinus lifts. Radiological results, although promising, must be further applied in long term clinical survival of the implants in the grafted sites. Also, studies combining L-PRF in conjunction with xenograft might bring improved clinical results in terms of reduced postoperative complications and accelerated healing. ng. 
  

A Randomized Controlled Trial Evaluating the Impact of Sinus Membrane Thickness and Sinus Dimensions on the Effectiveness of Two Graft Materials in Sinus Bone Augmentation

A Randomized Controlled Trial Evaluating the Impact of Sinus Membrane Thickness and Sinus Dimensions on the Effectiveness of Two Graft Materials in Sinus Bone Augmentation

Maxillary sinus floor augmentation with autogenous bone graft compared with composite grafts: A one-year single-blinded randomized controlled trial.

The objective was to assess the one year implant treatment outcome and patient-related outcome measures (PROMs) following maxillary sinus floor augmentation (MSFA) with autogenous bone graft (ABG) from the zygomatic buttress (control) compared with 1:1 mixture of ABG and anorganic porcine bone mineral (APBM) (Test I) or biphasic bone graft material (BBGM) (Test II). Sixty healthy patients (34 females, 26 males) were randomly allocated to either control or test groups. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of peri-implant tissue, peri-implant marginal bone loss, frequency of complications, and PROMs using Oral Health Impact Profile-14 combined with questionnaire assessing patient perception of peri-implant soft tissue, prosthetic solution, implant function, and implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was .05. All suprastructures and implants were well-functioning after one year of functional implant loading. There was no significant difference between control and test groups in any of the applied outcome measures. The implant stability significantly increased from implant placement to abutment connection within all groups (p < .001). High patient satisfaction and significant improvement in oral health-related quality of life was also reported within all groups. This study demonstrates that MSFA with composite grafts containing minimal amounts of ABG reveals comparable implant treatment outcomes as compared with ABG alone, after one year of functional implant loading. Extensive ABG harvesting in conjunction with MSFA therefore seems not to be needed.

Predictors of Success of Endonasal Septal Perforation Repair: A 10-Year Experience.

Background: There is no consensus on optimal repair technique for nasal septal perforations (NSPs). Objective: To measure success rate and evaluate predictors of success for NSP repair. Methods: Medical records of patients who underwent NSP repair from 2010 to 2020 were reviewed. Included patients had at least 60 days of postsurgical follow-up. Surgical technique involves an endonasal approach; subperichondrial dissection with local flap mobilization; and multilayer closure using cartilage interposition graft, fascia graft, and mucoperichondrial flaps. A chi-squared test or Fisher exact test was used for statistical analysis. Results: Eighty-one repairs were performed with a closure rate of 86%. The median patient age was 46 years (range 13-77); 34.6% of perforations were ≥2 cm. Conchal (77.8%), rib (7.4%), or septal (7.4%) cartilage was used as graft material. A complication rate of 8.6% was reported. Perforation size or graft material had no impact on successful closure rate. Of patients with failed repairs, 55% had perioperative complications or conditions associated with poor healing. Conclusion: An endonasal approach for NSP repair showed a high success rate across diverse presentations; however, NSP repair was significantly more likely to be successful in patients without perioperative complications or pre-existing conditions associated with poor wound healing.

One-Stage Lateral Sinus Floor Elevation Using Different Grafts: A Systematic Review of Controlled Clinical Trials.

The purpose of this systematic review was to assess histological and imaging outcomes related to new bone formation around implants, inserted simultaneously with sinus augmentation, comparing different types of grafts. Systematic Review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta- Analysis (PRISMA), and the Cochrane Handbook for Systematic Reviews of Interventions. LILACS/BVS, Medline/PubMed, Cochrane Library and Embase databases, including gray literature and manual investigation, were searched to identify clinical trials reporting human histological and imaging data of bone formation around implants, inserted into the maxillary sinus at the same moment of the elevation and augmentation procedure, using several materials. Study selection, risk of bias (Rob 2.0 or ROBINS I), quality of evidence (GRADE), and data collection were performed by two independent reviewers. Of the 1101 potentially eligible articles, 44 were retrieved, 12 were assessed for eligibility and 5 were included in this systematic review (4 randomized and one controlled clinical trials). As a result, 130 grafted sinuses with 179 installed implants in 103 patients, aged between 24 and 79 years and followed up from 6 to 15 months, were analyzed. The heterogeneity between studies did not allow the data to be combined for meta-analyses. All graft materials proved to be viable options for the intervention. The use of BCP was related to higher bone-to-implant contact. All the assessed grafts are viable options for the intervention addressed. The use of some material is justified to maintain the sinus volume and allow bone formation in the apical site of implants under the sinus membrane. Longer chair time and the morbidity of the donor site should be considered when choosing autogenous bone. Synthetic biphasic materials can be selected for this intervention due to superior values of %BIC when compared to DBB.

Measurement System for Compliance in Tubular Structures

Tubular structures such as blood vessels, intestines, and the trachea are common in various life forms. This paper describes a measurement system to test the mechanical compliance of tubular structures. The novelty of the system lies in its hardware and software. Here we use vascular graft as an example to demonstrate the utility of the system. A fully synthetic vascular graft would ideally mimic the mechanical and architectural properties of a native blood vessel. Therefore, mechanical testing of the graft material under physiological pressure is crucial to characterizing its potential in vivo performance. The device operates through a low-cost Arduino-based control system that simulates and measures cyclic fluid pressure changes over time and a laser micrometer that measures diameter changes with pressure. This system is low-cost, assuming one already has access to a laser micrometer. In contrast to previous methods, this system offers a simple, low-cost, and customizable option to measure compliance and is equipped with data acquisition/analysis programs. These programs include a MATLAB application that processes and synchronizes Arduino Uno pressure signals and LabChart Pro diameter readings. Lastly, this paper explains the hardware and software of the measurement system. The system is beneficial for testing the pressure-diameter relationship of tubular structures of varying sizes and materials. KEYWORDS: Tubular Structures; Compliance; Data Acquisition System; Physiological Pressure; Diameter Change; Arduino Uno; LabChart Pro; MATLAB

CLINICAL AND RADIOGRAPHIC ASSESSMENT OF BOND APATITE IN HORIZONTAL BONE AUGMENTATION AROUND DENTAL IMPLANTS: A RANDOMIZED CONTROLLED TRIAL

Background:Bond apatite is a composite graft, composed of two-thirds biphasic calcium sulfate and one-third hydroxyapatite granules of various sizes and shapes. Oral implants are used to secure dental prostheses in cases of partial or total edentulism. The outcomes of correctly completed dental-implant procedures result in high rates of success and survival of dental prostheses. Objective:The aim of this study was to assess Bond Apatite use in horizontal bone augmentation around dental implants, clinically and radiographically. Materials and Methods:This research included sixteen patients, six men and ten women, with an average age of thirty years having missing maxillary anterior or premolar teeth with insufficient horizontal bone. The patients were divided into two groups: group I patients (N=8) received dental implants with Bond apatite, while group II patients (N=8) received dental implants with Bio-Oss bone graft material and pericardium bioresorbable membranes. All patients were evaluated clinically usingthe modified plaque index (MPI), modified gingival index (MGI) and probing depth (PD) and radiographically to assess bone width dimensions. Results: There was a statistically significant difference between groups regarding MGI(p = 0.038)andperi-implant buccal PD [mm](p = 0.026). There was no statistically significant difference between the tested groups regarding age(p = 0.608), sex(p = 0.123), MPI(p = 0.608),orperi-implant palatalPD [mm](p = 0.118). There was no statistically significant difference between the two groups regarding postoperative bone width (p = 0.187). Conclusion:Bond apatitemay be used as one of the materials of choice for horizontal bone augmentation around dental implants with similar promising results compared to Bio-Oss. Finally, the use of Bond apatite preparation is a straightforward, affordable, and considered successful bone graft material that could be used in osseous defect reconstruction procedure. Trial registration:The study is listed on www.clinicaltrials.gov with registration number (NCT06043258) 22/09/2023. The study was conducted in accordance with the seventh revision of the Helsinki Declaration in 2013 and approved by the Institutional Review Board (IRB) (M07061119) of the Faculty of Dentistry, Mansoura University, Egypt.

Exploiting light-based 3D-printing for the fabrication of mechanically enhanced, patient-specific aortic grafts

Despite polyester vascular grafts being routinely used in life-saving aortic aneurysm surgeries, they are less compliant than the healthy, native human aorta. This mismatch in mechanical behaviour has been associated with disruption of haemodynamics contributing to several long-term cardiovascular complications. Moreover, current fabrication approaches mean that opportunities to personalise grafts to the individual anatomical features are limited. Various modifications to graft design have been investigated to overcome such limitations; yet optimal graft functionality remains to be achieved. This study reports on the development and characterisation of an alternative vascular graft material. An alginate:PEGDA (AL:PE) interpenetrating polymer network (IPN) hydrogel has been produced with uniaxial tensile tests revealing similar strength and stiffness (0.39 ± 0.05 MPa and 1.61 ± 0.19 MPa, respectively) to the human aorta. Moreover, AL:PE tubular conduits of similar geometrical dimensions to segments of the aorta were produced, either via conventional moulding methods or stereolithography (SLA) 3D-printing. While both fabrication methods successfully demonstrated AL:PE hydrogel production, SLA 3D-printing was more easily adaptable to the fabrication of complex structures without the need of specific moulds or further post-processing. Additionally, most 3D-printed AL:PE hydrogel tubular conduits sustained, without failure, compression up to 50% their outer diameter and returned to their original shape upon load removal, thereby exhibiting promising behaviour that could withstand pulsatile pressure in vivo. Overall, these results suggest that this AL:PE IPN hydrogel formulation in combination with 3D-printing, has great potential for accelerating progress towards personalised and mechanically-matched aortic grafts.

Using bone cement in re-bridging incudostapedial joint

Objective: to evaluate the hearing outcomes of using ionomeric bone cement in re-bridging incudostapedial joint discontinuity. Methods: This study included 50 patients who had ossiculoplasty using ionomeric bone cement for re-bridging of incudostapedial joint. There pre and post-operative audiologic outcomes were evaluated and reviewed by using pure tone audiometry averages and the air bone gap values with a follow up period of one year. Results: 42 patients (84%) had a post-operative air bone gap less than 20 dB following one year of surgery. The pre and post-operative mean of pure tune averages were 50.04±7.28 and 32.74±7.07 respectively (P value&lt;0.01). The pre and post-operative mean of air bone gap were 36.56±6.41 and 17.60±5.77 respectively which was statistically significant (P value&lt;0.01). Conclusion: using of ionomeric bone cement is a good grafting material in incudostapedial re-bridging ossiculoplasty being cost effective, easy applicable and biocompatible and give a satisfactory hearing outcome in selected patients.

The Effect of Platelet-Rich Fibrin and Platelet-Rich Plasma in Secondary Alveolar Bone Grafting in Cleft Lip and Palate Patients: A Systematic Review.

(1) Background: Cleft lip, alveolus, and palate are the most common congenital abnormalities in the world, occurring in one in seven hundred live births. Secondary alveolar bone grafting (SABG) is usually performed when the permanent canine root shows one-half to two-thirds of root development. To improve the surgical outcome, supplemental grafting materials such as platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) have been used as an adjunct. This review is designed to assess the efficacy of PRF and PRP in improving the outcome of SABG. (2) Methods: A comprehensive literature search was performed until 13 October 2022 on MEDLINE, EMBASE, The Cochrane Library, and Pubmed. The full text of potentially relevant studies was reviewed, and only randomised clinical trials (RCTs) were included based on the inclusion criteria. (3) Results: A total of 656 studies were screened, of which four were included for final review. All of the four included studies that evaluated the quantitative or qualitative surgical outcome in varied ways. (4) Conclusions: Results of this review suggest that both PRF or PRP and control group (without the use of PRF/PRP) achieved similar successful outcomes in bone height, bone density, and bone volume in both qualitative and quantitative assessment.

Major clinical outcomes of the alveolar ridge preservation post-extraction sockets: a systematic review

Introduction: After tooth extraction, the alveolar ridge will commonly decrease in volume and change morphologically. These changes can be difficult or even impede the placement of dental implants and prosthetic rehabilitation. Minimizing bone remodeling means optimizing the esthetics and functional aspects, and mainly, the success of implant treatment. To avoid residual ridge resorption different techniques and bone graft materials have been proposed. Objective:  It was to evaluate the efficiency of the many techniques of extraction socket treatment in the alveolar ridge dimension preservation. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from November 2023 to February 2024 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 158 articles were found, 62 articles were evaluated in full and 34 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 28 studies with a high risk of bias and 22 studies that did not meet GRADE and AMSTAR-2. Most studies did not show homogeneity in their results, with X2=63.6%&gt;50%. It was concluded that the application of autologous growth factor concentrate after surgical extraction offers an easy, low-cost, and efficient option for preserving the alveolar ridge. Therefore, the use of autologous growth factor concentrate by dentists during tooth extractions can be encouraged, especially when preservation of the alveolar ridge is necessary. The present study suggests that the alveolar graft technique may increase the risk of disease transmission, cost, and time of treatment. Several studies have stated that the graft material is not fully incorporated into the newly formed bone, indicating less vital bone tissue. Spontaneous scarring is still the most used feature since, in intact alveoli and small defects, it is a procedure that does not present significant losses that justify the use of edge preservation techniques. In larger defects, techniques after spontaneous healing, such as a block graft, can be used without the drawbacks of alveolar grafting, such as delayed healing and poor bone qualit.

Direct inkjet writing of polylactic acid/β-tricalcium phosphate composites for bone tissue regeneration: A proof-of-concept study.

There is an ever-evolving need of customized, anatomic-specific grafting materials for bone regeneration. More specifically, biocompatible and osteoconductive materials, that may be configured dynamically to fit and fill defects, through the application of an external stimulus. The objective of this study was to establish a basis for the development of direct inkjet writing (DIW)-based shape memory polymer-ceramic composites for bone tissue regeneration applications and to establish material behavior under thermomechanical loading. Polymer-ceramic (polylactic acid [PLA]/β-tricalcium phosphate [β-TCP]) colloidal gels were prepared of different w/w ratios (90/10, 80/20, 70/30, 60/40, and 50/50) through polymer dissolution in acetone (15% w/v). Cytocompatibility was analyzed through Presto Blue assays. Rheological properties of the colloidal gels were measured to determine shear-thinning capabilities. Gels were then extruded through a custom-built DIW printer. Space filling constructs of the gels were printed and subjected to thermomechanical characterization to measure shape fixity (Rf) and shape recovery (Rr) ratios through five successive shape memory cycles. The polymer-ceramic composite gels exhibited shear-thinning capabilities for extrusion through a nozzle for DIW. A significant increase in cellular viability was observed with the addition of β-TCP particles within the polymer matrix relative to pure PLA. Shape memory effect in the printed constructs was repeatable up to 4 cycles followed by permanent deformation. While further research on scaffold macro-/micro-geometries, and engineered porosities are warranted, this proof-of-concept study suggested suitability of this polymer-ceramic material and the DIW 3D printing workflow for the production of customized, patient specific constructs for bone tissue engineering.