Angela De Lauretis

• Lauretis, Angela De; Santacroce, Marco; Wang, Qiang; Ramirez, Manuel; Ma, Qianli & Lyngstadaas, Ståle Petter [Vis alle 9 forfattere av denne artikkelen] (2026). Combined Chemical and Mechanical Debridement Enhances Salivary Protein Removal from Titanium while Maintaining Biological Properties. ACS Biomaterials Science and Engineering. doi: 10.1021/acsbiomaterials.5c01973. Fulltekst i vitenarkiv Vis sammendrag

  Effective decontamination of dental implants is essential for managing peri-implant diseases, yet its impact on the salivary pellicle and cell response remains unclear. As the pellicle mediates bacterial and host cell interactions, investigating how decontamination alters its composition is key to understanding the effects on biological outcomes. Accordingly, we examined how a Poloxamer 407 (P407) hydrogel, a P407 + hydrogen peroxide (H2O2) hydrogel, a titanium brush, and their combinations influence the adsorbed salivary proteins and cell adhesion on OsseoSpeed-like titanium surfaces. Surfaces with salivary proteins were treated with different decontamination methods and re-exposed to saliva. Protein quantity was measured using the BCA assay, while the proteomic composition and molecular functions of the adsorbed proteins were determined by liquid chromatography-mass spectrometry and gene ontology analysis. Human bone marrow mesenchymal stem cell (hBMMSC) adhesion was assessed on the surfaces, and cytotoxicity was evaluated using an LDH assay. Protein-coated and protein-free surfaces served as controls. Although protein levels were consistent across groups after either decontamination or recontamination, each treatment produced a different proteomic profile. Mechanical decontamination, alone or combined with chemicals, enhanced protein removal efficiency. Combined treatments yielded reduced protein diversity following recontamination and enriched adhesion-related proteins. None of the treatments compromised hBMMSC adhesion nor made the surface cytotoxic. Decontamination methods selectively modify the proteomic profile. Combined chemical and mechanical decontamination promotes the removal of salivary proteins and limits their readsorption while preserving cytocompatibility, supporting their relevance to peri-implant health.

• Lauretis, Angela De; Wang, Qiang; Santacroce, Marco; Thiede, Bernd; Ma, Qianli & Lyngstadaas, Ståle Petter [Vis alle 9 forfattere av denne artikkelen] (2025). A Comparative Study of the Impact of Chemical Debridement Products on the Proteomic Profile of the Salivary Pellicle and Cell Adhesion on OsseoSpeed Titanium Dental Implant Surfaces. ACS Applied Materials & Interfaces. ISSN 1944-8244. 17(39), s. 54592–54592. doi: 10.1021/acsami.5c14570. Fulltekst i vitenarkiv
• Lauretis, Angela de; Wang, Qiang; Santacroce, Marco; Thiede, Bernd; Ma, Qianli & Lyngstadaas, Ståle Petter [Vis alle 9 forfattere av denne artikkelen] (2025). A Comparative Study of the Impact of Chemical Debridement Products on the Proteomic Profile of the Salivary Pellicle and Cell Adhesion on OsseoSpeed Titanium Dental Implant Surfaces. ACS Applied Materials & Interfaces. ISSN 1944-8244. 17, s. 54579–54592. doi: 10.1021/acsami.5c14570. Fulltekst i vitenarkiv Vis sammendrag

  Background and objectives: Dental implants are commonly used for tooth replacement, with excellent success rates over 10 years. However, exposure to oral cavity bacteria makes them susceptible to biofilm accumulation, which can lead to peri-implant diseases. The salivary pellicle, a protein-rich layer formed on implant surfaces, mediates bacterial adhesion and cell attachment. Effective decontamination is essential for managing bacterial infections, yet no consensus exists on the best chemical agent. Understanding how chemical agents affect the pellicle proteomic profile may guide the selection of optimal treatments. Methods: We investigate the impact of chemical decontamination agents on the salivary pellicle on OsseoSpeed-like titanium dental implant surfaces using a BCA assay and proteomics, and on cell adhesion using human gingival fibroblasts (HGF) and human bone marrow mesenchymal stem cells (hBMSC). We compare the effects of hydrogen peroxide (H2O2), Poloxamer 407 (P407), P407 + H2O2 and sodium hypochlorite + amino acids (NaOCl + AA) using the salivary pellicle and a clean titanium surface as controls. By quantifying and identifying proteins on titanium surfaces after decontamination, this study reveals how chemical agents affect the salivary pellicle. Results: All products reduced the total protein on the surfaces, with the P407 + H2O2 hydrogel demonstrating lower protein variety and superior effectiveness in preventing surface recontamination. Not all proteins were removed during decontamination procedures, and unique proteins were detected in each experimental condition, suggesting protein readsorption depends on surface chemistry. P407 + H2O2 shows the highest enrichment in integrin- and cadherin-binding proteins upon recontamination. P407 and P407 + H2O2 promoted HGFs and hBMSCs attachment. Conversely, NaOCl + AA and H2O2 showed lower HGFs and hBMSCs counts. Conclusion: The P407 + H2O2 hydrogel had the strongest decontamination effect and limited surface recontamination. Each chemical agent produced a distinct proteomic profile. P407 and P407 + H2O2 promoted initial cell adhesion.

• Lauretis, Angela de; Agger, Anne Eriksson; Pal, Antara; Pedersen, Jan Skov; Szostak, Szymon Mikolaj & Lund, Reidar [Vis alle 10 forfattere av denne artikkelen] (2025). Balancing sterilization and functional properties in Poloxamer 407 hydrogels: comparing heat and radiation techniques. Regenerative Biomaterials. 12. doi: 10.1093/rb/rbaf005. Fulltekst i vitenarkiv Vis sammendrag

  Poloxamer 407, also known as Pluronic® F127, is gaining interest in the cosmetic, biomedical, and pharmaceutical fields for its biocompatibility, safety, and thermosensitive properties. Ensuring sterility is critical in clinical applications, and sterilization is often preferred over aseptic processing. However, sterilization can impact the hydrogel's functional properties. In this study, we investigate the effects of steam heat (121°C, 20 min), dry heat (160°C, 1 h), gamma irradiation (25 kGy), and electron beam (e-beam) irradiation (15 kGy and 25 kGy) on a 30%w/v Poloxamer 407 hydrogel formulation. Our analysis encompasses gelling properties, pH, Fourier-transform infrared (FTIR) spectroscopy, Gel Permeation Chromatography (GPC), Small-angle X-ray scattering (SAXS), rheology, swelling, degradation by-products, and lactate dehydrogenase (LDH) release of the sterilised hydrogels, comparing them to a non-sterile counterpart. We demonstrated that heat sterilisation alters the hydrogel’s gelling and structural properties due to water evaporation and oxidation under harsh temperature conditions, especially when applying the dry heat method. Gamma irradiation proved unsuitable, resulting in an acidic and cytotoxic hydrogel due to oxidative degradation. In contrast, e-beam irradiation preserves the hydrogel's elasticity, gelling, and structural properties while enhancing mechanical resilience and moderating swelling. Therefore, e-beam irradiation within the 15 – 25 kGy range appears to be the most suitable method for sterilizing a 30%w/v Poloxamer 407 hydrogel.

• Lauretis, Angela de; Santacroce, Marco; Ellingsen, Jan Eirik; Lyngstadaas, Ståle Petter; Linke, Dirk & Haugen, Håvard Jostein (2025). Surface-specific outcomes of mechanical debridement with titanium, chitosan and nitinol brushes on titanium dental implant surfaces. Journal of Dentistry. ISSN 0300-5712. doi: 10.1016/j.jdent.2025.106010. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Dental implants are susceptible to peri‑implant inflammation caused by bacterial biofilms, with surface properties playing a key role in bacterial adhesion and osseointegration. While mechanical debridement is essential for biofilm removal, consensus on the optimal tool remains limited. In this study, we evaluate the impact of a titanium, a chitosan and a nitinol brush on the surface properties of four titanium dental implant surfaces: OsseoSpeed®-like, SLActive®-like, machined, and polished. Methods Profilometry, contact angle measurements, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) were used to assess the surface properties and chemistry. Results SEM and profilometry revealed that the titanium and nitinol brushes altered the morphology and topography of the rough OsseoSpeed®-like and SLActive®-like surfaces, while these effects were less pronounced on machined surfaces. Conversely, the chitosan brush caused minimal changes, but its bristles wore down quickly by physical abrasion, increasing surface carbon as detected by EDX and identified by XPS as organic material. Conversely, XPS confirmed that carbon contamination in samples treated with metal brushes was primarily environmental. The increased hydrophobicity observed across all groups was linked to carbon contamination. Polished surfaces remained unaffected by mechanical debridement. Conclusions The chitosan brush showed minimal surface alterations, but the rapid bristle wear left organic residues that increased hydrophobicity. The titanium and nitinol brushes caused more pronounced surface changes, while contributing to increased hydrophobicity through environmental carbon contamination during debridement. Clinical significance Dental implant surface properties, including topography, morphology, wettability, and surface chemistry, play a critical role in bacterial adhesion and osseointegration. Selecting an optimal mechanical debridement instrument requires balancing the effective removal of biofilm with the impact on the implant surface properties.

• Øvrebø, Øystein; Giorgi, Zoe; Lauretis, Angela De; Vanoli, Valeria; Castiglione, Franca & Briatico-Vangosa, Francesco [Vis alle 10 forfattere av denne artikkelen] (2024). Characterisation and biocompatibility of crosslinked hyaluronic acid with BDDE and PEGDE for clinical applications. Reactive & functional polymers. ISSN 1381-5148. 200. doi: 10.1016/j.reactfunctpolym.2024.105920. Fulltekst i vitenarkiv Vis sammendrag

  Hyaluronic acid (HA) is a versatile biomaterial frequently utilized in regenerative medicine due to its gel-like properties, making it well-suited for clinical applications. However, its linear form is susceptible to rapid enzymatic degradation, limiting its longevity within the body. To address this challenge, extensive research has focused on crosslinking mechanisms to enhance the durability of HA gels. One early approach involved crosslinking HA with 1,4-butanediol diglycidyl ether (BDDE) to create HA-BDDE, a clinically used product since the 1990s. However, the manufacturing process for HA-BDDE, primarily used in industry, lacks comprehensive documentation in the literature. More recently, poly(propylene glycol) diglycidyl ether (PEGDE) has emerged as an alternative to BDDE for crosslinking, offering improved gel elasticity and reduced cytotoxicity. In this study, we present the manufacturing process for producing both crosslinked gels, HA-BDDE and HA-PEGDE, with negligible residual crosslinkers, as confirmed by FTIR and NMR analysis. We characterize the crosslinking kinetics and the resulting formulations, revealing that HA-PEGDE gel exhibits comparable stiffness (G' = 60 Pa vs. 75 Pa) to HA-BDDE, despite a lower effective crosslinking ratio (CrR = 0.12 vs. 0.24). Intriguingly, our cytotoxicity testing demonstrates significantly greater cell viability for HA-PEGDE compared to HA-BDDE (151% versus 108%). Overall, both gels can be readily manufactured using a similar process and demonstrate excellent in vitro biocompatibility. This study elucidates why HA-BDDE is widely utilized in clinical settings and underscores the potential promise of HA-PEGDE as an emerging variant for clinical applications.

• Lauretis, Angela De; Øvrebø, Øystein; Romandini, Mario; Lyngstadaas, Ståle Petter; Rossi, Filippo & Haugen, Håvard Jostein (2024). From Basic Science to Clinical Practice: A Review of Current Periodontal/Mucogingival Regenerative Biomaterials. Advanced Science. doi: 10.1002/advs.202308848. Fulltekst i vitenarkiv Vis sammendrag

  Periodontitis is a dysbiosis-driven inflammatory disease affecting the tooth-supporting tissues, characterized by their progressive resorption, which can ultimately lead to tooth loss. A step-wise therapeutic approach is employed for periodontitis. After an initial behavioural and non-surgical phase, intra-bony or furcation defects may be amenable to regenerative procedures. This review discusses the regenerative technologies employed for periodontal regeneration, highlighting the current limitations in the field and future research areas. Our search, performed on the MEDLINE database, has identified the available biomaterials, including biologicals (autologous platelet concentrates, hydrogels), bone grafts (pure or putty), and membranes. Biologicals and bone grafts have been critically analysed in terms of composition, mechanism of action, and clinical applications. Although a certain degree of periodontal regeneration is predictable in intra-bony and class II furcation defects, complete defect closure is hardly achieved. Moreover, treating class III furcation defects remains challenging. We discuss the key properties required for functional regeneration, and none of the commercially available biomaterials possess all the ideal characteristics. Therefore, research is needed to promote the advancement of more effective and targeted regenerative therapies for periodontitis. Lastly, we suggest improving the design and reporting of clinical studies by strictly adhering to the CONSORT 2010 statement.

• Øvrebø, Øystein; Lauretis, Angela De; Ma, Qianli; Perale, Giuseppe; Nilsen, Ola & Rossi, Filippo [Vis alle 7 forfattere av denne artikkelen] (2024). Towards bone regeneration: Understanding the nucleating ability of proline-rich peptides in biomineralisation. Biomaterials Advances. ISSN 2772-9516. 159. doi: 10.1016/j.bioadv.2024.213801. Fulltekst i vitenarkiv Vis sammendrag

  Obtaining rapid mineralisation is a challenge in current bone graft materials, which has been attributed to the difficulty of guiding the biological processes towards osteogenesis. Amelogenin, a key protein in enamel formation, inspired the design of two intrinsically disordered peptides (P2 and P6) that enhance in vivo bone formation, but the process is not fully understood. In this study, we have elucidated the mechanism by which these peptides induce improved mineralisation. Our molecular dynamics analysis demonstrated that in an aqueous environment, P2 and P6 fold to interact with the surrounding Ca2+, PO4 3− and OH− ions, which can lead to apatite nucleation. Although P2 has a less stable backbone, it folds to a stable structure that allows for the nucleation of larger calcium phosphate aggregates than P6. These results were validated experimentally in a concentrated simulated body fluid solution, where the peptide solutions accelerated the mineralisation process compared to the control and yielded mineral structures mimicking the amorphous calcium phosphate crystals that can be found in lamella bone. A pH drop for the peptide groups suggests depletion of calcium and phosphate, a prerequisite for intrinsic osteoinduction, while S/TEM and SEM suggested that the peptide regulated the mineral nucleation into lamella flakes. Evidently, the peptides accelerate and guide mineral formation, elucidating the mechanism for how these peptides can improve the efficacy of P2 or P6 containing devices for bone regeneration. The work also demonstrates how experimental mineralisation study coupled with molecular dynamics is a valid method for understanding and predicting in vivo performance prior to animal trials

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• Lauretis, Angela de; Santacroce, Marco; Hussain, Badra; Ma, Qianli; Ellingsen, Jan Eirik & Lyngstadaas, Ståle Petter [Vis alle 8 forfattere av denne artikkelen] (2025). A poloxamer-peroxide forumulation effectively removes pellicle and limits recontamination. Fulltekst i vitenarkiv
• Lauretis, Angela de; Hussain, Badra; Ma, Qianli; Ellingsen, Jan Eirik; Lyngstadaas, Ståle Petter & Haugen, Håvard Jostein (2024). A comparative evaluation of chemical decontamination products on the cleanliness of dental implant surfaces using a dental pellicle model. Fulltekst i vitenarkiv Vis sammendrag

  Dental implants are widely employed for tooth replacement, but complications such as peri-implant infections may arise due to bacterial adhesion and biofilm formation, facilitated by the protein-rich salivary pellicle formed on the implant surface. Ensuring the cleanliness of the implant surface is crucial for long-term success and maintenance of peri-implant health.

• Lauretis, Angela de; Lyngstadaas, Ståle Petter; Ellingsen, Jan Eirik & Haugen, Håvard Jostein (2024). Decontamination dental implant surfaces using a dental pellicle mode. Fulltekst i vitenarkiv
• Lauretis, Angela De; Hussain, Badra; Ellingsen, Jan Eirik; Lyngstadaas, Ståle Petter & Haugen, Håvard Jostein (2024). A comparative evaluation of chemical decontamination products on the cleanliness of dental implant surfaces using a dental pellicle model. Fulltekst i vitenarkiv
• Lauretis, Angela De (2026). Decontamination of Titanium Dental Implant Surfaces: Mechanical and Chemical Strategies Targeting Salivary Proteins. Universitetet i Oslo. ISSN 9788283271072. Fulltekst i vitenarkiv Vis sammendrag

  This thesis presents mechanical and chemical methods for the removal of salivary proteins from titanium dental implant surfaces while preserving surface biological properties. Salivary proteins form a conditioning layer on implant surfaces that affects bacterial adhesion, highlighting the importance of understanding how cleaning methods affect these proteins. A titanium brush demonstrated efficient mechanical decontamination, removing salivary proteins while maintaining surface properties relevant for healing. Poloxamer 407 (P407) hydrogels were used as chemical decontamination agents, showing effective removal of salivary proteins, particularly when combined with hydrogen peroxide, while maintaining cytocompatibility. The combined application of mechanical and chemical approaches further promoted decontamination efficiency and supported cell adhesion. Sterilization studies on the P407 hydrogels revealed that moist heat and electron beam irradiation preserved their functionality, whereas dry heat and gamma irradiation induced degradation. Overall, the findings support the use of titanium brushes and P407 hydrogels as complementary tools for titanium implant surface decontamination.

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