Biomaterials for Periodontal Regeneration.

As a widespread chronical disease, periodontitis progressively destroys tooth-supporting structures (periodontium) and eventually leads to tooth loss. Therefore, regeneration of damaged/lost periodontal tissues has been a major subject in periodontal research. During periodontal tissue regeneration, biomaterials play pivotal roles in improving the outcome of the periodontal therapy. With the advancement of biomaterial science and engineering in recent years, new biomimetic materials and scaffolding fabrication technologies have been proposed for periodontal tissue regeneration. This article summarizes recent progress in periodontal tissue regeneration from a biomaterial perspective. First, various guide tissue regeneration/guide bone regeneration membranes and grafting biomaterials for periodontal tissue regeneration are overviewed. Next, the recent development of multifunctional scaffolding biomaterials for alveolar bone/periodontal ligament/cementum regeneration is summarized. Finally, clinical care points and perspectives on the use of biomimetic scaffolding materials to reconstruct the hierarchical periodontal tissues are provided.

Multicompartmental Scaffolds for Coordinated Periodontal Tissue Engineering.

Successful periodontal repair and regeneration requires the coordinated responses from soft and hard tissues as well as the soft tissue-to-bone interfaces. Inspired by the hierarchical structure of native periodontal tissues, tissue engineering technology provides unique opportunities to coordinate multiple cell types into scaffolds that mimic the natural periodontal structure in vitro. In this study, we designed and fabricated highly ordered multicompartmental scaffolds by melt electrowriting, an advanced 3-dimensional (3D) printing technique. This strategy attempted to mimic the characteristic periodontal microenvironment through multicompartmental constructs comprising 3 tissue-specific regions: 1) a bone compartment with dense mesh structure, 2) a ligament compartment mimicking the highly aligned periodontal ligaments (PDLs), and 3) a transition region that bridges the bone and ligament, a critical feature that differentiates this system from mono- or bicompartmental alternatives. The multicompartmental constructs successfully achieved coordinated proliferation and differentiation of multiple cell types in vitro within short time, including both ligamentous- and bone-derived cells. Long-term 3D coculture of primary human osteoblasts and PDL fibroblasts led to a mineral gradient from calcified to uncalcified regions with PDL-like insertions within the transition region, an effect that is challenging to achieve with mono- or bicompartmental platforms. This process effectively recapitulates the key feature of interfacial tissues in periodontium. Collectively, this tissue-engineered approach offers a fundament for engineering periodontal tissue constructs with characteristic 3D microenvironments similar to native tissues. This multicompartmental 3D printing approach is also highly compatible with the design of next-generation scaffolds, with both highly adjustable compartmentalization properties and patient-specific shapes, for multitissue engineering in complex periodontal defects.

A Review of Tissue Engineering for Periodontal Tissue Regeneration.

Periodontal disease is one of the most common diagnoses in small animal veterinary medicine. This infectious disease of the periodontium is characterized by the inflammation and destruction of the supporting structures of teeth, including periodontal ligament, cementum, and alveolar bone. Traditional periodontal repair techniques make use of open flap debridement, application of graft materials, and membranes to prevent epithelial downgrowth and formation of a long junctional epithelium, which inhibits regeneration and true healing. These techniques have variable efficacy and are made more challenging in veterinary patients due to the cost of treatment for clients, need for anesthesia for surgery and reevaluation, and difficulty in performing necessary diligent home care to maintain oral health. Tissue engineering focuses on methods to regenerate the periodontal apparatus and not simply to repair the tissue, with the possibility of restoring normal physiological functions and health to a previously diseased site. This paper examines tissue engineering applications in periodontal disease by discussing experimental studies that focus on dogs and other animal species where it could potentially be applied in veterinary medicine. The main areas of focus of tissue engineering are discussed, including scaffolds, signaling molecules, stem cells, and gene therapy. To date, although outcomes can still be unpredictable, tissue engineering has been proven to successfully regenerate lost periodontal tissues and this new possibility for treating veterinary patients is discussed.

A new digital evaluation protocol applied in a retrospective analysis of periodontal plastic surgery of gingival recessions.

This research aimed to develop a new digital evaluation protocol to objectively quantify the volumetric changes of root coverage periodontal plastic surgery when combined with connective tissue graft. Consecutive patients with Cairo recession type 1 (RT1) or Cairo recession type 2 (RT2) were treated. Accurate study models obtained at baseline and follow-ups were optically scanned. Healing dynamics were measured by calculating volume differences between time points. Nineteen patients were treated between December 2014 and January 2019. At 3-month follow-up, root coverage was 95.6% (± 14.5%) with tunnel and connective tissue graft (TUN + CTG) technique, and 88.9% (± 20.5%) with the vestibular incision subperiosteal tunnel access and connective tissue graft (VISTA + CTG) technique. Recession decreased 1.33 (± 0.86) mm and 1.42 (± 0.92) mm, respectively (p = 0.337). At 6-month follow-up, root coverage was 96.5% (± 10.4%) with the TUN + CTG and 93.9% (± 10.3%) with the VISTA + CTG. Recession decreased 1.35 (± 0.85) mm and 1.45 (± 0.82) mm, respectively (p = 0.455). Complete root coverage was achieved in 86.7% (± 0.4%) with TUN + CTG and 70.6% (± 0.5%) with VISTA + CTG. No statistically significant differences were found between techniques. The digital protocol presented proved to be a non-invasive technique for accurate measurements of clinical outcomes. Both techniques reduce gingival recessions, with no statistically significant differences.

Crosstalk between RNA-Binding Proteins and Immune Microenvironment Revealed Two RBP Regulatory Patterns with Distinct Immunophenotypes in Periodontitis.

Periodontitis is an inflammatory disease whose pathogenesis is closely related with immunology. RNA-binding proteins (RBPs) were found to play crucial roles in immunity. Therefore, we aimed to investigate the potential impact of RBPs in the immune microenvironment in periodontitis. The differential expressions of RBPs in periodontitis and healthy samples were determined and were used to construct an RBP-based classifier for periodontitis using logistic regression. The correlations between RBPs and immune characteristics were investigated by the Spearman correlation. Unsupervised clustering was conducted to identify the RBP regulatory patterns. RBP-related genes were identified by WGCNA, while biological distinctions were revealed by GSVA and GO. 24 dysregulated RBPs were identified, from which a 12-RBP classifier was established to distinguish periodontitis with AUC of 0.942. Close protein-protein interactions and expression correlations were observed especially between SPATS2 and ISG20. ISG20 and ESRP1 were found to be highly correlated with immunocyte infiltration, immune signaling activation, and HLA expressions in periodontitis. Two distinct RBP regulatory patterns were identified with different immune and other biological characteristics in periodontitis. Our findings indicate a significant impact of RBPs in shaping the immune microenvironment in periodontitis, which might bring new insights into the understanding of immune mechanisms in the pathogenesis of periodontitis.

Use of Platelet-Rich Fibrin in the Treatment of Periodontal Intrabony Defects: A Systematic Review and Meta-Analysis.

BACKGROUND: Platelet-rich fibrin (PRF) is a kind of autologous platelet concentrate which is easy to obtain and cheap. In recent years, it has been studied to improve the effect of periodontal regeneration. However, few studies have systematically evaluated the complementary effect of PRF in the treatment of intrabony defects. The present review is aimed at systematically assessing the effects of PRF on clinical and radiological outcomes of the surgical treatment of periodontal intrabony defects. METHODS: The protocol was registered at PROSPERO (International Prospective Register of Systematic Reviews) as CRD42020206056. An electronic search was conducted in MEDLINE, Cochrane, and EMBASE databases. Only randomized clinical trials were selected. Systematically healthy patients with two or three walls of intrabony defects were considered. Intrabony defect (IBD) depth reduction and bone fill (BF) % were set as primary outcomes while probing depth (PD) reduction, clinical attachment level (CAL) gain, and gingival margin level (GML) gain were considered as the secondary outcome. When possible, a meta-analysis was performed. RESULTS: Eighteen articles fulfilled the inclusion criteria, and seventeen studies were quantitatively analyzed. Of 17 studies, four were rated as high risk of bias and thirteen as the moderate risk of bias. Two comparisons were set: (1) open flap debridement (OFD) combined with PRF and OFD alone and (2) bone grafting (BG) combined with PRF and BG alone. Compared to OFD alone, OFD+PRF showed significantly greater in all primary and secondary outcomes. Compared to BG alone, BG+PRF showed significantly greater in IBD depth reduction, PD reduction, CAL gain, and GML gain. CONCLUSIONS: The use of PRF was significantly effective in the treatment of periodontal intrabony defects. The benefit of OFD+PRF may be greater than BG+PRF. PRF can promote early wound healing in periodontal surgery. As all included studies were not at low risk of bias, well-designed RCTs having a high methodological quality are needed to clarify the additional effectiveness of PRF in the treatment of intrabony defects in the future.

The effect of low-level laser therapy as an adjunct to periodontal surgery in the management of postoperative pain and wound healing: a systematic review and meta-analysis.

The meta-analysis and systematic review aimed to evaluate the effect of low-level laser therapy (LLLT) as an adjunct to periodontal surgery in the management of postoperative pain and wound healing. An electronic search in 4 databases (PubMed, Embase, Cochrane, and OpenGrey) was conducted for randomized clinical trials reporting the effectiveness of LLLT used as an adjunct to periodontal surgery to alleviate pain and accelerate wound healing compared with surgery alone. Finally, 13 studies were eligible and included. The results showed a significant difference of pain relief between groups at day 3 post-surgery, whereas no difference was found at day 7. Moreover, a significant reduction was observed in the mean analgesic intake during the first week in the LLLT group. On day 14, the adjunctive use of LLLT showed significantly faster re-epithelialization and better wound healing in palatal donor sites following free gingival graft procedures. Based on the results, LLLT used as an adjunct to periodontal surgery positively influenced postsurgical pain control. Low power (≤ 500 mW) combined with energy density ≥ 5 J/cm2 might be more appropriate for postoperative pain relief. Moreover, adjunctive LLLT to free gingival grafts could significantly accelerate wound healing of palate sites at early healing phase. Multicenter studies using different LLL parameters without postsurgical analgesics are needed to determine optimal laser settings.

Simultaneous Perio-endo Surgery with ER:YAG Laser and Bone Xenograft. A Case Report.

Periodontally affected teeth with periapical lesion indicated for periapical surgery have a poor prognosis. Using Er:YAG lasers to perform simultaneous surgery on both defects may increase their survival rate. Preparing a retrograde cavity on affected teeth and obturating it is still a matter of debate among clinicians. The purpose of this case report was to describe the simultaneous use of Erbium-doped Yttrium Aluminium Garnet Er:YAG (2,940 nm) laser in the treatment of periapical granuloma and infraossal defect and the achieved results. The Er:YAG laser was used to perform flap dissection, granulation tissue removal, osteotomy and root-end resection except for initial flap incision and reflection. The cystic cavity was filled with Bio-Oss Collagen® xenograft. Results were followed up for 18 months with the help of radiographic orthopantomographic images. The outcome of this clinical case indicates that the use of Er:YAG laser could be considered a suitable method to perform simultaneous periodontal and endodontic surgery.

Patient-reported outcomes of laser-assisted pain control following non-surgical and surgical periodontal therapy: A systematic review and meta-analysis.

Adjunctive use of laser devices as high reactive-level laser/light therapy (HLLT) or photobiomodulation therapy (PBMT) for periodontal therapy is known to be more effective on suppressing pain than conventional therapy, however, there are no systematic reviews addressed its effectiveness. This systematic review and meta-analysis aim to investigate the following clinical question (CQ): does adjunctive use of lasers with conventional therapy suppress the pain associated with periodontal treatment? A systematic and extensive literature search was performed to summarize the currently available knowledge to answer the CQ using the PubMed, Cochrane Library, and Web of Science databases for randomized controlled trials (RCTs) conducted before June 2020. Bias risk was assessed using the Cochrane tool for the risk of bias evaluation. A meta-analysis was performed on quantitative evaluation of pain control based on patient-reported outcomes. After an independent screening of 165 initial records, ten RCTs were included. Six of them focused on surgical procedures and the others on non-surgical periodontal pocket therapy. The protocols of HLLT, PBMT, and combination with HLLT and PBMT were employed in five, four and one RCTs, respectively. Following the assessment of bias risk, it is revealed that all RCTs had methodological weaknesses regarding the blinding of key personnel, although other bias risk factors were not evident. Meta-analysis showed that HLLT using erbium lasers significantly reduced the patient-reported pain immediately after treatment (two RCTs, p < 0.0001), while PBMT using diode lasers significantly reduced pain 2-7 days after treatment (two RCTs, p < 0.0001 to p = 0.03). The presented systematic review and meta-analysis suggest that the alternative use of HLLT using erbium lasers to conventional instrumentation can significantly suppress postoperative pain and that intraoperative or postoperative PBMT using diode lasers combined with periodontal surgery can significantly reduce postoperative pain. However, the evidence is still insufficient and more well-designed RCTs are required.

The use of enamel matrix derivative for the treatment of the apically involved tooth: A case report.

INTRODUCTION: The aim of this report is to present a case of an apically involved tooth with successful regeneration by only applying enamel matrix derivative. The root of the tooth was planed and the defect area was well debrided using various instruments, including curettes and an ultrasonic scaler, and the root surface of the tooth and the defect area were loaded with enamel matrix derivative. PATIENT CONCERNS: A 32-year-old man visited the clinic due to a referral for the evaluation of his mandibular left first molar. DIAGNOSIS: The clinical and radiographic assessment displayed the loss of the periodontium around the tested tooth with apical involvement of the mesial root. Bleeding upon probing was noted at the mandibular first molar, with the deepest periodontal probing depth of 15 mm. INTERVENTIONS: A nonsurgical approach was firstly performed on the tooth, and the deepest probing depth was reduced to 12 mm. After re-evaluation, elevation of a full-thickness flap was done, the root of the tooth was planed, and the defect area was well debrided using various instruments, including curettes and an ultrasonic scaler. The defect area on the mandibular left first molar was grafted with enamel matrix derivative. OUTCOMES: The 7-month postoperative clinical and radiographic evaluation showed healthy gingiva and an increase in radiopacity. The final 1-year and 9-month postoperative evaluation showed that regeneration of bony defect was well maintained up to the final evaluation with reduction of probing depth. CONCLUSION: In conclusion, a case of apically involved tooth can be treated only with enamel matrix derivative after meticulous debridement with curettes and an ultrasonic scaler.

Connective Tissue Graft Stabilization by Subperiosteal Sling Suture for Periodontal Plastic Surgery Using the VISTA Approach.

This report describes a minimally invasive surgical approach using the vestibular incision subperiosteal tunnel access and a suture called the subperiosteal sling (SPS) to stabilize the connective tissue graft (CTG) for periodontal plastic surgery. The SPS suture engages only the CTG and stabilizes the CTG against the tooth independent of the overlying tissue, which minimizes the risk of graft mobility caused by muscle movement.

Effects of NSAIDs on Periodontal and Dental Implant Therapy.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly prescribed group of drugs in dentistry for managing postoperative pain and discomfort. Little is known regarding their effects on the healing of periodontal and peri-implant tissues. METHODS: The authors conducted a review of the literature to provide an overview of knowledge about NSAIDs and their potential effects on periodontal and implant wound healing. RESULTS: A Pubmed (MEDLINE) database search was conducted to identify articles evaluating the influence of administration of NSAID drugs on outcomes following periodontal treatments (nine clinical studies) and dental implant placement (four animal studies and two human clinical studies). Conflicting results were found on the effects of NSAIDs during periodontal wound healing. NSAID administration, specifically selective COX-2 inhibitors could inhibit bone formation around orthopedic implants. CONCLUSION: Within the limitations of this review, NSAIDs negatively affected osseointegration of titanium implants. However, quality of evidence from available human clinical studies is poor and there are conflicting results from animal models. Future and better clinical studies are needed to more precisely evaluate the potential effects of NSAIDs on dental wound healing. PRACTICAL IMPLICATIONS: Dental surgeons must be aware of the potential effects of NSAID use on osseous healing following common oral surgical procedures such as periodontal and implant therapy.

Soft tissue augmentation at immediate implants using a novel xenogeneic collagen matrix in conjunction with immediate provisional restorations: A prospective case series.

BACKGROUND: Collagen matrices used around immediate implants may reduce morbidity although there is limited evidence on their performance. PURPOSE: To evaluate soft and hard tissue changes when combining immediate implants, hard and soft tissue grafting, and an immediate provisional restoration. MATERIAL AND METHODS: In 12 patients, immediate implants were placed in the anterior maxillary and first premolar area together with a xenogeneic bone substitute. Then a xenogeneic collagen matrix was placed under the buccal mucosal margin with an immediate provisional restoration. Study casts and clinical measurements were taken before extraction (Baseline/BS) at 6 months (6M) and 12 months (1Y) after implant placement. Files from the scanned casts were matched to calculate the linear and volumetric changes at the buccal tissues. Cone Bean Computed Tomographies (CBCTs) were taken prior to extraction and at 6M. The superimposed DICOM files allowed for assessing hard tissue changes and the superimposition of DICOM and STL files allowed for evaluating of soft tissue thickness at BS and 6M. RESULTS: After 6 months, the horizontal tissue contours decreased 0.66 ± 0.57 mm, concomitant with a horizontal bone loss of 1.31 ± 1.32 mm, measured 1 mm below the most coronal aspect of the ridge. In contrast, the soft tissue thickness, 1 mm below the gingival margin, increased 0.75 ± 1.12 mm. At 1-year, tissue contours had decreased 1.01 ± 0.67 mm compared to BS reaching statistical significance. The mean volume loss after 1Y was 20.43 ± 11.70 mm3 while the mean mucosal margin recession was 0.86 ± 0.67 mm. These changes had a limited clinical impact as the PES Scores remained stable. CONCLUSIONS: The tested protocol resulted in a significant reduction of the tissue contours and osseous ridge dimensions that was partially compensated by a non-significant increase in soft tissue thickness.

Effects of Occlusion on Periodontal Wound Healing.

Trauma from occlusion remains an important concept in dentistry. Traumatic occlusion affects the biological system through a series of events that induces an aseptic inflammatory response and bone resorption. Clinical evidence of these biological events is present in the form of active traumatic lesions or adaptive mechanisms. If these clinical signs are not identified prior to periodontal surgery, failure of the procedure could result due to an exacerbated leukocyte presence and unresolving wound. However, if traumatic occlusion is adjusted, evidence demonstrates that even large inflammatory events such as replantation of an avulsed tooth can be successful. Thus, harmony of occlusal contacts without interference is essential in achieving predictable periodontal/implant bone regeneration.

Classification of Soft Tissue Grafting Materials Based on Biologic Principles.

Since periodontal plastic surgery's recent emergence and continuous, extensive development, various treatment modalities and materials have been developed alongside it to help clinicians pursue optimal esthetics and long-term stability around natural teeth and dental implants. To achieve satisfying and predictable long-term outcomes, promote more predictable results, and reduce complications following periodontal plastic surgery procedures, the authors reviewed articles published in peer-reviewed journals to better understand the biologic principles and potential of the soft tissue grafting materials and techniques being applied. That information was used to support a new classification system. This system aims to give clinicians guidance when selecting the most appropriate grafting materials and techniques for periodontal plastic surgery, using the graft materials' two most important features to guide the consideration/decision process: the source of blood supply and whether the grafts contain vital cells.

Histological and micro-CT analysis of peri-implant soft and hard tissue healing on implants with different healing abutments configurations.

OBJECTIVE: The aim of this study was to assess the effect of different abutment configurations on peri-implant soft and hard tissue healing. MATERIALS AND METHODS: Two-piece dental implants, 3.5 mm in diameter and 8 mm in length, were placed in four beagle dogs. Two different transmucosal healing abutment configurations were randomly selected: one with a wide emergence profile (WE) (45° angulation with implant long axis) and the other with a narrow emergence profile (NE) (15° angulation with implant long axis). After four months of healing, the animals were sacrificed. Micro-CT scans were taken for mesio-distal analysis; subsequently, the biopsies were prepared for bucco-lingual histometric analyses. Several measurements were taken using the following reference points: marginal mucosal level (MML), apical barrier epithelium (aBE), implant shoulder (IS), marginal bone crest (BC), and first bone-to-implant contact (fBIC). RESULTS: In the micro-CT analysis, the distance from IS-fBIC was 1.11 ± 0.66 mm for WE and 0.12 ± 0.21 mm for NE (p = 0.004). The IS-BC of WE was -0.54 ± 0.80 mm, whereas NE presented 0.76 ± 0.48 mm (p = 0.002). The histometric analysis showed that both groups presented comparable dimensions of peri-implant biologic width (p > 0.05). However, in the distance from IS to BC, the WE showed a mean distance of -0.66 ± 0.78 mm while NE was 0.06 ± 0.42 mm (p = 0.039); the IS to fBIC was 0.89 ± 0.68 mm for WE while NE was 0.30 ± 0.30 mm (p = 0.041). CONCLUSION: The design of the transmucosal component can influence the establishment of the peri-implant biologic width. The flat and wide emergence profile induced an apical displacement of the peri-implant biologic width and more bone loss.

[Periodontal interception in children and adolescents. The role of periodontal plastic surgery: before? during? afterwards?] / L'interception parodontale chez l'enfant et l'adolescent. Place de la chirurgie plastique parodontale : avant ? pendant ? après ?

INTRODUCTION: Orthodontic treatment of children and adolescents must take into account their specific immature periodontal status. The decision to treat a situation entailing a periodontal risk has thus to be thought out more thoroughly than with adult patients.The basic problem lies in finding a proper balance between early treatment, which avoids any possible worsening linked to a risk-related situation, and monitoring, which avoids over-correction, at the risk of seeing the situation deteriorate during orthodontic treatment. A thorough orthodontic and periodontal examination will help identify the gingival biotypes and orthodontic movements liable to endanger the patient's periodontal health. OBJECTIVES: The aim is to ensure that a specific periodontal treatment plan can be designed for each young patient and to enable a rapid response in the event of any occurrence or deterioration of a periodontal defect. MATERIALS AND METHODS: The authors make several suggestions in order to get closer to the true situation and take the right decision regarding the difficult choice between interception and monitoring. CONCLUSION: Very regular follow-ups will be needed more often than with adults. Frequent appointments will enable the clinician to follow the progress of the periodontium, as well as the young patient's maturation process, making it possible to intervene quickly if recession occurs or worsens.

Changes in Peri-implant Soft Tissue Thickness with Bone Grafting and Dermis Allograft: A Case Series of 15 Consecutive Patients.

Immediate implant placement and provisional restoration has become a popular and well-supported method of tooth replacement in the maxillary anterior dentition. Aside from achieving osseointegration, esthetic demands have grown with better understanding of the behavior of hard and soft tissues following this mode to therapy. Stability of gingival contours, texture of the surrounding tissues, and blending of prosthetic components with the natural dentition are critical for successful outcomes to be maintained long-term. Increasing soft tissue thickness at the time of therapy plays an important role in this regard. A technique combining the proven principles of immediate implant placement and provisional restoration with hard and soft tissue augmentation using nonautogenous materials is demonstrated with comparisons to nongrafted, temporized historical controls.

Nonincised Papillae Surgical Approach (NIPSA) in Periodontal Regeneration: Preliminary Results of a Case Series.

A new surgical approach has been developed to optimize the preservation of the gingival margin and papillae when treating periodontal defects. The flap is raised by one mucosal incision far away from the marginal tissues. This case series reports on the effectiveness of a nonincised surgical approach (NIPSA) in conjunction with a hydroxyapatite-based graft biomaterial and enamel matrix derivative in treating intrabony defects. Ten defects in 10 patients were treated. The follow-up period ranged from 6 to 18 months (mean: 10.8 ± 4.7 months). Probing pocket depth was 9.6 ± 2.3 mm before surgery and 2.3 ± 0.5 mm postsurgery. Clinical attachment level (CAL) decreased from 10.4 ± 2.7 mm to 3.1 ± 0.87 mm postsurgery. The gingival papilla height, keratinized tissue width, and buccal gingival margin remained stable over time. No wound dehiscence was recorded. Mean Early Healing Index was 1.5 ± 0.7. Results show a substantial CAL gain, limited postsurgical shrinkage, minimal morbidity, and early healing.