Xenogenic collagen matrix or autologous connective tissue graft as adjunct to coronally advanced flaps for coverage of multiple adjacent gingival recession: Randomized trial assessing non-inferiority in root coverage and superiority in oral health-related quality of life

Guided-modified coronally advanced flap: Novel digital approach to treat multiple gingival recessions. Workflow and case study

BACKGROUND

Gingival recession (GR) poses esthetic and functional challenges for patients, particularly in cases of multiple adjacent defects. Traditional surgical approaches, such as the modified coronally advanced flap (MCAF) with connective tissue grafts (CTG), demand high levels of precision and skill, making outcomes reliant on clinician expertize. The integration of digital technologies, including cone-beam computed tomography (CBCT) and computer-aided design and manufacturing (CAD-CAM), offers a novel, standardized approach to enhance procedural accuracy and predictability.

METHODS

This case study describes the use of the guided-modified coronally advanced flap (g-MCAF) for the treatment of multiple GR defects. A patient whose main concern was the esthetic appearance of her teeth was treated. Using an intraoral scanner, CBCT data, and CAD-CAM software, surgical guides were designed and 3D printed using a dedicated resin, assuring precise adaptation to the patients' teeth. The guides delineated MCAF oblique incisions and free gingival graft dimensions tailored to fit into the area, facilitating flap design, and graft harvesting.

RESULTS

The guided MCAF (g-MCAF) procedure successfully achieved complete root coverage. At the 6-month follow-up, recession reduction was observed, measuring 2.22 mm for tooth #5, 2.59 mm for tooth #6, and 2.26 mm for tooth #7. Gingival thickness also increased, reaching 1.23, 1.16, and 1.45 mm, respectively. Additionally, the patient reported improved esthetics and reduced hypersensitivity.

CONCLUSION

The g-MCAF technique may have the potential to serve as a reliable aid to execute MCAF in the management of multiple GR defects.

KEY POINTS

A guided surgical approach (g-MCAF) using digital technologies allows for precise flap design and graft harvesting, which may help control variability and minimize errors during root coverage procedures. The integration of CBCT, intraoral scanning, and CAD-CAM technologies supports preoperative planning, potentially contributing to safer and more predictable outcomes, particularly in cases requiring connective tissue grafts. This innovative approach may assist in simplifying complex surgical techniques, improving clinician confidence, and serving as both a clinical and an educational tool for periodontal plastic surgery.

3D Bioprinting and Artificial Intelligence-Assisted Biofabrication of Personalized Oral Soft Tissue Constructs

Regeneration of oral soft tissue defects, including mucogingival defects associated with the recession or loss of gingival and/or mucosal tissues around teeth and implants, is crucial for restoring oral tissue form, function, and health. This study presents a novel approach using three-dimensional (3D) bioprinting to fabricate individualized grafts with precise size, shape, and layer-by-layer cellular organization. A multicomponent polysaccharide/fibrinogen-based bioink is developed, and bioprinting parameters are optimized to create shape-controlled oral soft tissue (gingival) constructs. Rheological, printability, and shape-fidelity assays, demonstrated the influence of thickener concentration and print parameters on print resolution and shape fidelity. Artificial intelligence (AI)-derived tool enabled streamline the iterative bioprinting parameter optimization and analysis of the interaction between the bioprinting parameters. The cell-laden polysaccharide/fibrinogen-based bioinks exhibited excellent cellular viability and shape fidelity of shape-controlled, full-thickness gingival tissue constructs over the 18-day culture period. While variations in thickener concentrations within the bioink minimally impact the cellular organization and morphogenesis (gingival epithelial, connective tissue, and basement membrane markers), they influence the shape fidelity of the bioprinted constructs. This study represents a significant step toward the biofabrication of personalized soft tissue grafts, offering potential applications in the repair and regeneration of mucogingival defects associated with periodontal disease and dental implants.

Effects of photobiostimulation and antimicrobial photodynamic therapy associated with gingival grafts for root coverage: three-arm randomized clinical trial

To compare the effects of different laser therapies as adjuncts to root coverage of multiple gingival recessions (MGR) through a three-arm parallel study. Fifty-four patients with MGR underwent standardized treatment with subepithelial connective tissue graft of 1 mm. The patients were divided into three groups: control group (C)-scaling only + sham (n = 18), antimicrobial photodynamic therapy (APDT) group (n = 18): toluidine blue O 10 mg/ml acidic pH + InAlGaP laser 660 nm; 100 mW, 2.32 W/cm2; 3 J, 30 s/tooth, (23 J/cm2/point), and photobiostimulation therapy (PBM) group (n = 18): InAlGaP laser 660 nm; 100 mW, 2.32 W/cm2; 7 J, 70 s/flap, 161 J/cm2 (23 J/cm2/point), a total of eight applications, each 48 h, within a 14-day period. Patient-Reported Outcome Measures (PROMs), and quality of life questionnaires (OHIP- 14) were collected up to 12 months. A total of 180 gingival recessions were treated, with the PBM group exhibiting superior outcomes in terms of complete root coverage (CRC) at 6 and 12 months. Complementary clinical outcomes showed no significant differences among groups. The PBM group achieved the highest frequency of completely covered teeth (100%) at six months, compared to the other groups (p: 0.021 PBM vs. APDT and p: < 0.001 PBM vs. C). Despite the study's limitations, the PBM group exhibited more favorable outcomes in CRC and demonstrated superior results in PROMs. The findings suggest that PBM may have contributed to accelerating root coverage outcomes, with positive effects observed as early as 3 months postoperatively and the results were sustained at 6 and 12 months. NCT03462368.

Efficacy of concentrated growth factor combined with coronally advanced flap in the treatment of gingival recession: a systematic review and meta-analysis

OBJECTIVES

This study aims to evaluate the efficacy of combining the coronally advanced flap (CAF) technique with concentrated growth factor (CGF) in the treatment of gingival recession (GR), and to compare this approach with other alternative treatments.

METHODS

This systematic review and meta-analysis included randomized controlled trials (RCTs) comparing CAF combined with CGF to other treatments for root coverage procedures. Included studies evaluated systemically healthy adults (> 18 years) with Miller Class I/II or Cairo RT1 gingival recessions. Primary outcomes were complete root coverage (CRC) and mean root coverage (MRC); secondary outcomes included changes in keratinized tissue width (KTW), gingival thickness (GT), clinical attachment level (CAL), recession width (RW), recession depth (RD), and probing depth (PD). A comprehensive search was conducted across multiple databases, including PubMed, Scopus, Cochrane Library, Web of Science, and Embase, up to November 9, 2024. The study protocol was prospectively registered in PROSPERO (CRD42024556815). Statistical analyses were performed using Review Manager 5.4.1.

RESULTS

Eight studies were included in the meta-analysis. Compared to CAF alone, the combination of CAF and CGF significantly improved CRC (OR = 1.79, P = 0.04), MRC (MD = 10.38%, P = 0.04), KTW (MD = 0.40 mm, P = 0.02), GT (MD = 0.26 mm, P < 0.00001), and CAL (MD = 0.36 mm, P = 0.03). CAF combined with connective tissue graft (CTG) showed superior efficacy for CRC compared to CAF + CGF (OR = 0.25, P = 0.009). However, no significant differences were found between CAF + CTG and CAF + CGF for MRC, CAL, KTW, RD, RW, or PD. Additionally, no significant differences were observed when comparing CAF + CGF with CAF + PRF across all clinical parameters (all P > 0.05).

CONCLUSIONS

The findings of this meta-analysis indicate that CAF/CGF improves clinical outcomes in treating GR compared to CAF alone, and CGF may be a viable alternative to CTG when CTG is not applicable. Further studies are needed to validate the efficacy of CAF/CGF in the treatment of GR.

CLINICAL SIGNIFICANCE

In cases where CTG is not applicable, CGF may serve as a viable alternative for the treatment of Miller class I and II GR.

Long-term assessment of a modified tunneling technique for root coverage in lower anterior gingival recession: a retrospective study

PURPOSE

Root coverage (RC) procedures require long-term evaluation. This study assessed the clinical validity and long-term stability of a modified tunneling technique for lower anterior gingival recession (GR) using a subepithelial connective tissue graft (SCTG) and a volume-stable collagen matrix.

METHODS

Across 39 patients, 66 mandibular incisors with ≥1.0 mm of GR were examined before and after RC surgery. Clinical photographs documenting the results of RC were taken at baseline (T₀) and the most recent follow-up visit (Tl). Impressions were obtained either at baseline (T₀) or 3 weeks later (T₃). The recession depth, Miller classification, and rates of RC and complete root coverage (CRC) were assessed.

RESULTS

This study analyzed 66 GR sites across 39 patients, with an average follow-up period of 41.3 months. Overall, the mean RC achieved was 86.2%±15.7%. Among single recessions, the RC was 85.2%±25.6% for Miller class I, 91.5%±10.4% for class II, and 79.2%±18.3% for class III. Regarding multiple recessions, the RC was 85.1%±16.2% for Miller class I, 87.0%±12.5% for class II, and 89.8%±16.0% for class III. By Miller classification, the RC was 85.1%±16.8% for class I, 88.7%±11.6% for class II, and 85.8%±17.3% for class III. Furthermore, the RC varied by follow-up duration: 72.5%±15.1% at 12 months, 90.1%±12.6% at 25-36 months, 89.0%±16.7% at 37-48 months, 91.10%±9.88% at 49-60 months, and 97.6±4.79% for longer than 61 months, with 77.8% of the last group achieving CRC. RC also differed based on the initial recession depth, at 88.0%±16.8% for 1-3 mm, 83.1%±14.1% for 3-6 mm, and 80.2%±5.04% for depths exceeding 6 mm.

CONCLUSIONS

A modified tunneling technique, utilizing SCTG and a volume-stable collagen matrix, appears to represent a reliable option for the long-term management of GR in the lower anterior region, even in cases involving multiple Miller class III GRs.

Collagen Matrix Versus Subepithelial Connective Tissue for Recession Coverage: A Systematic Review

OBJECTIVE

To evaluate the outcome of collagen matrix (CMX) compared with subepithelial connective tissue graft (SCTG) in gingival recession coverage (RC) surgery.

METHODS

Review protocol was registered in PROSPERO. The search was conducted on MEDLINE, Cochrane Library, and Scopus databases. Randomized studies comparing CMX versus. SCTG or CMX versus. covering procedures without any filling material, for class I recession treatment were included. Risk of bias assessment and quantitative analysis were performed.

RESULTS

Of 168 records, 11 randomized clinical trials were included. The meta-analysis revealed no statistically significant difference in terms of %RC (p = 0.37); there was a statistically significant difference in terms of recession reduction (p = 0.02) and keratinized tissue width (p = 0.03) in favor of SCTG cases. CMX showed a statistically significantly better result compared to no grafting, regarding %RC (p = 0.003) and keratinized tissue thickness (p < 0.0001). The duration of the intervention was significantly shorter for CMX than for SCTG (p < 0.0001).

CONCLUSION

CMX can be considered a viable material, especially when a ΔKTt increase and a reduction of intervention duration is needed. The indications for the choice, however, may depend on the individual local condition. PROSPERO Registration: Registration in PROSPERO (International prospective register of systematic reviews): CRD42024555443.

Cellularized Biomaterials Used as Gingival Connective Tissue Substitutes In Vivo: A Systematic Review

Developing an in vitro model of gingival connective tissue that mimics the original structure and composition of gingiva for clinical grafting is relevant for personalized treatment of missing gingiva. Using tissue engineering techniques allows bypassing limitations encountered with existing solutions to increase oral soft tissue volume. This review aims to systematically analyze the different currently existing cellularized materials and technologies used to engineer gingival substitutes for in vivo applications. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. An electronic search on PubMed, Scopus, Web of Science, and Cochrane Library databases was conducted to identify suitable studies. In vivo studies about gingival substitutes and grafts containing oral cells compared with a control to investigate the graft remodeling were included. Risk of bias in the included studies was assessed using the Systematic Review Center for Laboratory animal Experimentation (SYRCLE) 10-item checklist. Out of 631 screened studies, 19 were included. Animal models were mostly rodents, and the most used implantation was subcutaneous. According to the SYRCLE tool, low-to-unclear risk of bias was prevalent. Studies checked vascularization and extracellular remodeling up to 60 days after implantation of the cellularized biomaterial. Cells used were mostly fibroblasts and stem cells from oral origin. Grafts presenting vascularization potential after implantation were produced by tissue engineering technologies including cell seeding or embedding for 14, cell sheets for 2, microsphere for 1, and extrusion 3D bioprinting for 2. Components used to build the scaffold containing the cells are all naturally derived and are mainly fibrin, gelatin, collagen, agarose, alginate, fibroin, guar gum, hyaluronic acid, and decellularized extracellular matrix. The most recurring crosslinking method was using chemicals. All studies except one reported vascularization of the graft after implantation, and some detailed extracellular matrix remodeling. Current solutions are not efficient enough. By assessing the relevant studies on the subject, this systematic review showed that a diversity of cellularized biomaterials substituting gingival connective tissue enables vascularization and extracellular remodeling. Taking the results of this review into account could help improve current bio-inks used in 3D bioprinting for in vivo applications compensating for gingival loss.

From tradition to innovation: a bibliometric analysis of the evolution of periodontal plastic surgery

PURPOSE

The aim of this study was to conduct a bibliometric analysis of the periodontal plastic surgery literature to identify trends, research gaps, and key themes within the field and to establish a perspective on documented research.

METHODS

This bibliometric study examined research outputs on mucogingival surgery indexed in the Web of Science database from 1990 to 2023. The Science Mapping Analysis Tool (SciMAT) software was used to visualize and predict research trends on this topic.

RESULTS

An analysis of publication distribution by year revealed a decline in the number of publications between 1984 and 1995, followed by an overall upward trend after 1996 despite occasional decreases. The United States contributed the most with 593 publications, and Wang HL (n=74) was the most prolific author. The most frequently used keyword was "gingival recession" (n=625). Overall, the publications received 44,859 citations, averaging 25.49 citations per publication.

CONCLUSIONS

Researchers have made significant efforts to improve clinical practices and procedures in periodontal plastic surgery, resulting in an increase in studies over recent years. By analyzing thematic maps and clusters-using indicators such as frequency, citations, and centrality-researchers can identify the strengths, weaknesses, and gaps in current research.

Polymer-Based Scaffolds as an Implantable Material in Regenerative Dentistry: A Review

Polymer-based scaffolds have emerged as transformative materials in regenerative dentistry, enabling the restoration and replacement of dental tissues through tissue engineering approaches. These scaffolds, derived from natural and synthetic polymers, mimic the extracellular matrix to promote cellular attachment, proliferation, and differentiation. Natural polymers such as collagen, chitosan, and alginate offer biocompatibility and bioactivity, while synthetic alternatives like polylactic acid (PLA) and polycaprolactone (PCL) provide tunable mechanical properties and degradation rates. Recent advancements highlight the integration of bioactive molecules and nanotechnology to enhance the regenerative potential of these materials. Furthermore, developing hybrid scaffolds combining natural and synthetic polymers addresses biocompatibility and mechanical strength challenges, paving the way for patient-specific treatments. Innovations in 3D bioprinting and stimuli-responsive biomaterials are expected to refine scaffold design further, improving therapeutic precision and clinical outcomes. This review underscores the critical role of polymer-based scaffolds in advancing regenerative dentistry, focusing on their applications, advantages, and limitations.

Endoscopic Re-Instrumentation of Intrabony Defect-Associated Deep Residual Periodontal Pockets Is Non-Inferior to Papilla Preservation Flap Surgery: A Randomized Trial

BACKGROUND AND AIM

Clinical practice guidelines suggest access flap surgery for managing deep residual pockets after steps 1 and 2 of periodontal therapy. Papilla-preservation flap surgery (PPFS) is the least invasive approach to access and instrument biofilm-contaminated root surfaces. Endoscopic-assisted subgingival debridement (EASD) may enhance the outcomes of repeated instrumentation and provide a minimally invasive non-surgical alternative.

METHODS

This was a single-blind, controlled, randomized, parallel-group, non-inferiority 12-month trial comparing EASD with PPFS. Male and female adults with generalized stage III periodontitis and persistent periodontal pockets associated with an intrabony defect after steps 1 and 2 of periodontal therapy were recruited at Prince Philip Dental Hospital. Inter-group differences in clinical attachment level (CAL) changes at 12 months were the primary outcome. Secondary outcomes included pocket resolution (no pocket > 5 mm and no pocket > 4 with bleeding on probing), radiographic bone changes, treatment time, early wound healing and quality-of-life measurements.

RESULTS

Sixty-two subjects (30 EASD and 32 PPFS) were included in the intention-to-treat analysis. CAL gains were 2.0 ± 1.0 and 1.8 ± 1.0 mm for test and controls, respectively. The 95% CI of the inter-group difference was -0.3 to 0.8 mm and within the stipulated 1-mm non-inferiority margin. No inter-group differences were observed (i) in pocket resolution, which was achieved in more than 87% of cases for all groups/time points, and (ii) in radiographic bone healing. The treatment time was significantly shorter for EASD than for PPFS. Better early wound healing index scores were observed for EASD. No inter-group differences in pain, quality of life or safety were detected.

CONCLUSIONS

EASD was not inferior to PPFS for managing residual pockets associated with intrabony defects. The observed outcome profile supports additional developments and studies to validate EASD as an alternative to surgery for isolated persistent pockets (ChiCTR-INR-16008407).

Autologous platelet concentrates in root coverage procedures

Gingival recessions are vastly prevalent among the general population. With regards to their treatment, recent advancements in periodontal and microsurgical procedures, focusing on minimal invasiveness and patient-centered therapies, have propelled a shift in their contemporary treatment, highlighting the field of biologics and bioactive mediators. Among different classes and types of biologics, autologous platelet concentrates (APCs), also referred to as autologous blood-derived products, are commonly used and preferred among many clinicians. These are essentially obtained via venipuncture (intravenous access) followed by centrifugation, for which numerous protocols and preparation methods have been used, leading to varieties of blood-derived products. In this review, via a systematic search, we explored the efficacy of the different utilized preparation methods and centrifugation protocols of APCs (e.g., platelet-rich plasma (PRP), platelet-rich fibrin (PRF), leucocyte-PRF, advanced-PRF, concentrated growth factor (CGF), etc.) for the treatment of type 1 gingival recessions (RT1, without interproximal attachment loss or noticeable tooth displacement), as well as their effectiveness relative to a common control (treatment with flap advancement alone without any additional material). Based on the available literature from randomized trials found in our systematic search, we observed that utilization of PRF can significantly enhance treatment outcomes when performing a coronally advanced flap, in terms of the amount of root coverage. The improvement in root coverage was further enhanced in the presence of baseline keratinized tissue width, and with an increasing relative magnitude (the more the baseline keratinized tissue width, the better the root coverage outcomes when using PRF). The efficacy of these products needs to be further explored with different graft substitutes and matrices, as well as relative to other commonly applied biologics, through well-conducted and adequately-powered randomized clinical trials.

Tissue Perfusion and Biomarkers Assessment Following Root Coverage Procedures

AIM

To assess tissue perfusion changes and wound healing biomarker levels after root coverage procedures with coronally advanced flap in combination with the cross-linked xenogeneic collagen matrix (CCMX), loaded either with a placebo or recombinant human platelet-derived growth factor-BB (rhPDGF).

METHODS

This study was designed as a secondary analysis from a previously published clinical trial, and it assessed the tissue perfusion changes over 6 months around multiple gingival recession defects, treated with either with CCMX alone (control) or with CCMX + rhPDGF (test). High frequency Doppler ultrasonography (HFUS) scans were obtained at sites of interest at baseline, 2 weeks, 3 months, and 6 months after surgery. Dynamic tissue perfusion measurements (DTPMs) were performed at the midfacial, interproximal, and transverse aspects of the teeth by an operator, blinded to treatment allocation, using a software package. The expression of different wound healing biomarkers from the gingival crevicular fluid was also assessed.

RESULTS

The regression analyses showed similar tissue perfusion changes between the two groups throughout the majority of the 6 months. DTPMs at 2 weeks showed the test group to have significantly higher perfusion relief intensity (pRI, p < 0.001), mean perfused area (pA, p < 0.001), mean blood flow intensity (FImean, p = 0.021), and total blood flow intensity (FItot, p = 0.021) at the graft region of interest (ROI) compared to control sites. The test sites also exhibited significantly greater pA (p = 0.033) and blood flow intensity "blue" (FIblue, meaning flow away from the transducer, p = 0.035) at the level of the flap compared to the control sites. At 2 weeks, FIblue of the graft was directly correlated with the final mean root coverage (p = 0.008) and complete root coverage (p = 0.003). FImean and FItot of the graft exhibited a direct correlation with volume gain at 6 months (p = 0.031 for both parameters). The final GT gain was correlated to the early DTPMs (pA and FIblue) of the graft and the flap. The two groups exhibited different expressions of IL-1β, PDFG-BB, and VEGF over 3 months, with the 1-week levels of PDGF-BB that were associated with time to recovery.

CONCLUSIONS

HFUS allowed exquisite assessment of tissue perfusion occurring at the entire surgical reconstructive regions and also within the flap and the graft. Sites treated with CCMX + rhPDGF exhibited higher DTPMs, primarily within the graft and flap ROIs at the 2-week timepoint compared to sites augmented with CCMX + saline. Early DTPMs at the graft and flap ROIs showed associations with PROMs and the final clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04462237.

Application of Collagen Matrix in Peri-Implant Dehiscence Defect: A Case Series

During implant placement, dehiscence defects can result in complications such as mucosal recession and peri-implantitis. Whereas guided bone regeneration (GBR) is a common approach to managing these defects, it is often complex and time-intensive. This case series evaluates an alternative method using a collagen matrix (Collagen Graft2) applied to peri-implant dehiscence defects without GBR. Through three case series, this approach effectively preserves buccal contour, enhances gingival thickness, and supports bone regeneration, leading to favorable peri-implant conditions. These findings suggest that collagen matrix application is a viable and less invasive option for treating peri-implant dehiscence defects; however, further studies are required to validate these results.

Efficacy of xenogeneic collagen matrix in the treatment of gingival recessions: a controlled clinical trial

This study aimed to evaluate the efficacy of a xenogeneic collagen matrix (XCM) in treating gingival recessions (GR) in a thin gingival phenotype. This double-blind, planned, controlled, split-mouth clinical trial included 30 patients with bilateral recessions, randomly assigned to a test group (extended flap + XCM) and a control group (extended flap + connective tissue graft; CTG). Root coverage at 18 months was 1.75 ± 0.8 mm (72.9%) and 2.4 ± 0.51 mm (88.9%) in the test and the control groups, respectively. The upper limit of the confidence interval was not greater than the non-inferiority margin of 0.69 mm. The increase in gingival thickness was greater for autogenous graft (p = 0.003). Both treatments improved quality of life at 18 months. The keratinized tissue width (KTW) increased significantly in the grafted teeth, in both the test (p < 0.001) and the control groups (p < 0.001). Total root coverage was similar in both groups, reaching 70% and 66.7% in the control and test groups, respectively, with no significant differences observed for partial or complete root coverage (CRC). An association was observed in the quality of the gingival phenotype at 18 months according to the treatment group, i.e., a higher percentage of cases with a thicker phenotype was observed in the control group (86.7%), compared with the test group (53.3%) (p = 0.005). XCM was effective in treating GR, but CTG had better results because of significantly increased gingival thickness and phenotypic conversion.

Impact of platelet-rich fibrin derivatives on patient morbidity and quality of life in palatal donor sites following free gingival graft surgery: a randomized clinical trial

OBJECTIVES

Platelet concentrates are biomaterials with significant potential in tissue regeneration, functioning as scaffolds with greater leukocyte inclusion and a flexible fibrin mesh. However these concentrates have different preparation methods and biological properties. The objective of this clinical investigation was to evaluate the effects of utilizing platelet-rich fibrin (PRF) materials (L-PRF and A-PRF) as a palatal bandage following free gingival graft (FGG) on patients' morbidity and oral health-related quality of life.

MATERIALS AND METHODS

Thirty-nine participants received FGG to promote keratinized tissue and treat gingival recession. Participants were randomly assigned to L-PRF, A-PRF, and control groups, with 13 participants in each. They used a visual analog scale (VAS) to rate their pain, analgesic medication use, dietary changes, discomfort, and bleeding at 1-7 days, 14 days and 1 month during the healing process. Patients' quality of life was assessed using the Oral Health Impact Profile (OHIP-14) at baseline, 1-7 days, 14 days, 1 month, and 6 months.

RESULTS

There was no difference in anxiety levels between the all groups. (p > 0.05). The control group had higher OHIP-14 total scores than the other groups, but the differences were not statistically significant, especially in the first seven days (p > 0.05). In addition, the PRF groups showed an improvement in quality of life after 14 days, 1 month, and 6 months (p < 0.05). Patients' pain and suffering decreased with healing. The control group took more postoperative analgesics than PRF groups. In addition, there was a significant decrease in patient complaints about medicine intake, bleeding, pain, perceived sensitivity, and dietary modifications in all groups during follow-up.

CONCLUSIONS

PRF palatal bandages may improve patient's quality of life, donor site healing, postoperative pain and morbidity.

CLINICAL RELEVANCE

This study found that preserving the palate in FGG and employing PRF materials that speed palate healing reduce discomfort and morbidity.

A preliminary investigation into the impact of soft tissue augmentation-based periodontal phenotype modification therapy for patients exhibiting class III decompensation

BACKGROUND

Patients with skeletal angle Class III malocclusion usually have inadequate hard and soft tissue volume at the mandibular anterior teeth. The labial proclination at the teeth may lead to gingival recession. The purpose of this study was to explore whether periodontal phenotype modification therapy with soft tissue augmentation (PhMT-s) can prevent gingival recession in these patients.

METHODS

Four patients with skeletal Class III malocclusion and a thin periodontal phenotype underwent surgical-orthodontic treatment. Prior to tooth movement, they underwent a minimally invasive vestibular incision with subperiosteal tunnel access combined with autogenous connective tissue grafts for periodontal phenotype modification with soft tissue augmentation (PhMT-s). The labial gingival thickness of the anterior mandibular teeth was measured at three distinct levels: at the cementoenamel junction (GT0), 3 mm apical to the CEJ (GT3), and 6 mm apical to the CEJ (GT6). These measurements were taken at baseline, three months following PhMT-s, and after tooth decompensation. Additionally, a biopsy sample was obtained from the PhMT-s site of one patient. All sections were subsequently stained using hematoxylin and eosin, Masson trichrome, Sirius Red, and immunohistochemistry.

RESULTS

The thickness of the labial gingiva was increased about 0.42 to 2.00 mm after PhMT-s. At the end of pre-orthognathic surgical orthodontic treatment, the thickness of the labial gingiva was increased about - 0.14 to 1.32 mm compared to the baseline and no gingival recession occurred after the pre-orthognathic surgical orthodontic treatment. The histologic results demonstrated that the grafts obtained from the PhMT-s site exhibited increased deposition of collagen fibers. Moreover, the proportion of type III collagen increased and the grafts displayed significantly reduced positive expression of CD31 and OCN.

CONCLUSIONS

PhMT-s increased the thickness of the soft tissue, stabilizing the gingival margin for teeth exhibiting a thin periodontal phenotype and undergoing labial movement. This is attributed to the increased deposition of collagen fibers.

Xenogeneic Collagen Matrix Versus Free Gingival Graft for Augmenting Peri-Implant Keratinized Mucosa Around Dental Implants: A Systematic Review and Meta-Analysis

OBJECTIVES

There is a growing evidence to suggest augmenting peri-implant keratinized mucosa in the presence of ≤ 2 mm of keratinized mucosa. However, the most appropriate surgical technique and augmentation materials have yet to be defined. The aim of this systematic review and meta-analyses was to evaluate the clinical and patient-reported outcomes of augmenting keratinized mucosa around implants using free gingival graft (FGG) versus xenogeneic collagen matrix (XCM) before commencing prosthetic implant treatment.

MATERIAL AND METHODS

Electronic databases were searched to identify observational studies comparing implant sites augmented with FGG to those augmented with XCM. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool.

RESULTS

Six studies with 174 participants were included in the present review. Of these, 87 participants had FGG, whereas the remaining participants had XCM. At 6 months, sites augmented with FGG were associated with less changes in the gained width of peri-implant keratinized mucosa compared to those augmented with XCM (mean difference 1.06; 95% confidence interval -0.01 to 2.13; p = 0.05). The difference, however, was marginally significant. The difference between the two groups in changes in thickness of peri-implant keratinized mucosa at 6 months was statistically significantly in favor of FGG. On the other hand, XCM had significantly shorter surgical time, lower postoperative pain score, and higher color match compared to FGG.

CONCLUSIONS

Within the limitation of this review, the augmentation of keratinized mucosa using FGG before the placement of the final prosthesis may have short-term positive effects on soft tissue thickness. XCM might be considered in aesthetically demanding implant sites and where patient comfort or shorter surgical time is a priority. The evidence support, however, is of low to moderate certainty; therefore, further studies are needed to support the findings of the present review.

Effect of Coenzyme Q10 on early wound healing after recession coverage surgery with the modified coronally advanced tunnel technique and a connective tissue graft: A 6-month, triple-blinded, randomized, placebo-controlled pilot trial

OBJECTIVES

Coenzyme Q10 (CoQ10) or ubiquinone is one of a cell's most important electron carriers during oxidative phosphorylation and many other cellular processes. As a strong anti-oxidant with further anti-inflammatory effects CoQ10 is of potential therapeutical value. The aim of this randomized controlled clinical trial was to investigate the effect of topical CoQ10 on early wound healing after recession coverage surgery using the modified coronally advanced tunnel (MCAT) and palatal connective tissue graft (CTG).

MATERIALS AND METHODS

Thirty patients with buccal gingival recessions were evaluated after being randomly allocated to: 1) MCAT and CTG with topical application of a coenzyme Q10 spray for 21 days or 2) MCAT and CTG with placebo spray. Wound healing was evaluated by the early wound healing index (EHI). Patient-reported pain was analyzed by a 100-mm visual analogue scale (VAS) at day 2, 7, 14 and 21 post-surgically. Mean recession coverage, gain of keratinized tissue and esthetic outcomes were assessed at 6 months.

RESULTS

EHI and pain scores showed no significant differences. Time to recovery defined as VAS<10 mm was shorter in the test group. Mean root coverage after 6 months was 84.62 ± 26.57% and 72.19 ± 26.30% for test and placebo, p=0.052. Complete root coverage was obtained in 9 (60%) test and in 2 (13.3%) placebo patients. Increase in keratinized tissue width and esthetical outcomes were similar for both groups.

CONCLUSION

CoQ10 had no significant effect on early wound healing and on mean root coverage after 6 months.

CLINICAL RELEVANCE

Early wound healing: in young healthy patients with no inflammatory oral conditions topical CoQ10 does not improve early healing.

Treatment of multiple adjacent gingival recessions using leucocyte- and platelet-rich fibrin with coronally advanced flap: a 12-month split-mouth controlled randomized clinical trial

OBJECTIVE

This split-mouth randomized study aimed to assess efficacy of leucocyte-platelet-rich fibrin (L-PRF) versus connective tissue graft (CTG) in achieving root coverage (RC) for multiple adjacent gingival recessions (MAGRs) throughout 12-month period.

MATERIALS AND METHODS

The study enrolled 59 teeth from 12 patients with Miller Class I MAGRs ≥ 2 mm on bilateral or contralateral sides. Patients were randomly assigned to receive coronally advanced flap (CAF) with either CTG (control) or L-PRF (test) treatment. Various parameters, including plaque and gingival index, clinical attachment level, recession depth, probing depth, recession width (RW), papilla width (PW), keratinized tissue width (KTW), gingival thickness (GT), percentage of RC, complete root coverage (CRC), and location of the relative gingival margin concerning the cemento-enamel junctions (GMCEJ) after CAF, were recorded at baseline, 3-, 6-, and 12-months post-surgery. On June 29, 2021 the study was registred to ClinicalTrials.gov (NCT04942821).

RESULTS

Except KTW and GT gain, all clinical parameters, RC, and CRC were similar between the groups at all follow-up periods (p > 0.05). The higher GT and KTW gains were detected in the control group compared to test group at 12 months (p < 0.05). Both RC and CRC were positively associated with initial PW and GMCEJ, but negatively with initial RW (p < 0.05).

CONCLUSIONS

The current study concludes that L-PRF were equally effective as CTG in treating MAGRs in terms of RC and CRC. Additionally, RC and CRC outcomes appeared to be influenced by GMCEJ, PW, and RW.

CLINICAL RELEVANCE

L-PRF could represent a feasible substitute for CTG in treating MAGRs.

Xenogeneic collagen matrix vs. connective tissue graft for the treatment of multiple gingival recession: a systematic review and meta-analysis

The aim of this systematic review (SR) compared the effect of xenogeneic collagen matrix (XCM) vs. connective tissue graft (CTG) for the treatment of multiple gingival recession (MGR) Miller Class I and II or Cairo type I. Five databases were searched up to August 2022 for randomized clinical trials (RCTs) comparing the clinical effects of XCM vs. CTG in the treatment of MGR. The random effects model of mean differences was used to determine reduction of gingival recession (GR), gain in keratinized tissue width (KTW), gain in gingival thickness (GT) and gain in clinical attachment level (CAL). The risk ratio was used to complete root coverage (CRC) at 6 and 12 months. 10 RCTs, representing 1095 and 649 GR at 6 and 12 months, respectively, were included in this SR. The meta-analysis showed no statistically significant difference in GR reduction, KTW gain GT gain or CAL gain between groups at 6 months. However, at 12 months of follow-up, differences favoring the control group were observed (p < 0.05). CRC was significantly higher in the CTG group at 6 and 12 months. Regarding dentine hypersensitivity (DH), no statistically significant differences were found between groups at 6 and 12 months of follow-up (p < 0.05). At 12 months, CTG showed significantly superior clinical results in the treatment of MGR: however, this difference was not observed in the decrease of DH.

Analysis of the treatment of RT2 recessions with a xenogeneic collagen matrix vs. connective tissue graft combined with a coronally advanced flap. A double-blinded randomized clinical trial

OBJECTIVES

To compare the clinical efficacy in terms of mean root coverage in RT2 recession treated with a coronally advanced flap combined with a xenogeneic collagen matrix versus a connective tissue graft.

MATERIALS AND METHODS

A total of 20 patients were randomized to receive one of two treatments: coronally advanced flap + xenogeneic collagen matrix (test group) and coronally advanced flap + connective tissue graft (control group). Patient-related outcomes measures and professional aesthetic assessment by root esthetic score were performed. A descriptive and analytical statistical analysis of the variables was performed.

RESULTS

At 12 months, the mean root coverage was 56.48% in the test group and 69.72% in the control group (p = 0.048), with a 35% and 40% complete root coverage in the xenogeneic collagen matrix and connective tissue graft, respectively. Test group presented less pain (3.65 vs. 5.2 VAS units) (p = 0.015) and less surgical time (45 vs. 49.15 min) (p = 0.004) than control group.

CONCLUSION

The use of xenogeneic collagen matrix in RT2 recessions was effective for recession reduction to those obtained using autologous grafts; with the advantage that the duration of surgery and patient morbidity decreased. Therefore, xenogeneic collagen matrix in RT2 recessions could be an alternative to autologous grafts.

CLINICAL RELEVANCE

The use of xenogeneic collagen matrix decreases the surgery time and patient morbidity but connective tissue graft results in significantly better mean root coverage and complete root coverage. Xenogeneic collagen matrix can be used in the treatment of RT2 gingival recessions.

STUDY REGISTRATION

NCT03344315.

Efficacy of acellular xenogeneic dermal matrix graft in the treatment of multiple gingival recessions: systematic review and meta-analysis

OBJECTIVE

This study aimed to compare the efficacy of acellular xenogeneic dermal matrix graft (AXDM) compared to connective tissue graft (CTG) in treating multiple gingival recessions.

MATERIALS AND METHODS

A systematic search of electronic databases was conducted to identify randomized clinical trials (RCTs) that compared AXDM and CTG. The selected studies were subjected to bias risk assessment, data extraction, and meta-analyses. Parameters such as gingival recession height, width, mean percentage of root coverage, and complete root coverage were analyzed.

RESULTS

Seven RCTs involving 146 patients were included. The meta-analyses indicated that CTG was statistically superior to AXDM in reducing gingival recession height at the final follow-up (mean difference: -0.104 mm, 95% confidence interval [CI]: -0.180-0.028, p = 0.008) and width at the final follow-up (mean difference: -0.285 mm, 95% CI: -0.541-0.030, p = 0.029). CTG also demonstrated a significantly higher mean percentage of root coverage at the 6-month follow-up (difference in means: -2.761 mm, 95% CI: -4.932-0.590, p = 0.013) and a higher percentage of complete root coverage at the 6-month follow-up (odds Ratio [OR]: 0.598, 95% CI: 0.4-0.892, p = 0.012) compared to AXDM. However, there was no significant difference in the number of teeth with complete root coverage between CTG and AXDM (OR: 1.610, 95% CI: 0.983-2.636, p = 0.058) and aesthetic outcomes (mean difference: 0.148, 95% CI: -0.277-0.573, p = 0.494).

CONCLUSIONS

CTG is more effective than AXDM in treating multiple gingival recessions. This is evidenced by significant reductions in gingival recession height and width, a higher mean percentage of root coverage, and a greater percentage of complete root coverage at the 6-month follow-up.

CLINICAL RELEVANCE

In some clinical situations an alternative to CTG is required for the treatment of multiple gingival recessions. AXDM, despite presenting clinical outcomes that are not as satisfactory as CTG, can be used for this purpose.

Parodontgel® on Wound Healing and Patient-Reported Outcome Measures (PROMs) after Tunneled Coronally Advanced Flap (TCAF)

The adjunctive use of healing gels following periodontal plastic surgery is not common in clinical practice, and no definitive benefits have yet been demonstrated. Case Presentation. A 33-year-old male patient with a central lower incisor class RT1 recession sought treatment due to sensitivity and dissatisfaction with the appearance of his smile. The patient had no history of periodontal disease; however, he was under orthodontic treatment contributing to the gingival recession and irregular gum contours. Treatment. The patient underwent two sequential surgical procedures. Initially, an apically repositioned flap (APF) was performed to correct the frenulum reducing flap tension and improving the gum line aesthetics. Subsequently, after 8 weeks, a tunneled coronally advanced flap (TCAF) was executed to further refine the gum contours and achieve root coverage. Postoperative Healing Protocol. To enhance the healing process and alleviate postoperative discomfort, a healing gel containing hyaluronic acid as the active molecule was applied to the surgical sites. The gel was expected to reduce pain perception and minimize the need for painkiller intake during the critical first week of recovery. The patient was asked to fill a pain chart for the initial 7 days, recording pain levels on a visual analogue scale (VAS 0-10) and the number of paracetamol tablets taken as painkillers. Results. After both the APF and TCAF surgeries, the patient reported pain levels with a mean VAS score of 4.33 and 4.25, respectively. The painkiller intake during the first week was noted to be 3 tablets for the APF and 2 tablets for the TCAF. Notably, the application of the healing gel with hyaluronic acid did not cause any adverse reactions, indicating its potential safety and efficacy in this context. Conclusion. The application of a healing gel containing hyaluronic acid after periodontal plastic surgery showed promising results in reducing postoperative pain and the need for painkillers during the initial week of recovery. However, further investigations through randomized clinical trials are required to establish the potential benefits and broader applicability of such healing gel applications in the context of periodontal plastic surgery.

The quality of life after keratinized mucosa augmentation around dental implants using xenogenic collagen matrix with or without stent

BACKGROUND

The substitution of missing teeth with implants is a dependable and anticipated therapeutic approach. Despite numerous studies affirming long-term success rates, there exists a spectrum of potential biological and aesthetic complications.

OBJECTIVE

The primary objective of this study was to assess patient responses subsequent to surgical interventions, with a specific emphasis on the utilization of xenogenic collagen matrix (XCM), both with and without the application of a stent secured over healing abutments, in the context of keratinized gingival mucosa augmentation. The principal aim was to evaluate and draw comparisons between the clinical outcomes resulting from these two procedural approaches, with a particular focus on critical parameters encompassing post-operative complications, patient comfort, and the overall efficacy in achieving successful keratinized tissue augmentation.

METHODS

Sixty patients were selected for this study. The patients were divided into three groups: A, B, and a control group, with each group comprising 20 participants. We used XCM in experimental group A, XCM covered with surgical stent in experimental group B, and free gingival graft (FGG) in the control group. After the surgical procedure, patients were required to complete a visual analogue scale (VAS) questionnaire for post-operative complications, and a quality of life (QOL) questionnaire on days 1, 3, and 7.

RESULTS

Patients in the experimental groups A and B demonstrated markedly improved outcomes when compared with the control group. Assessments conducted on days 1, 3, and 7 demonstrated diminished levels of pain, bleeding, and swelling in both experimental groups, with experimental group B showing the least discomfort. The incorporation of XCM, either with or without stents, was associated with a reduction in analgesic consumption, underscoring its favorable influence on post-operative comfort, notwithstanding the exception of halitosis in experimental group B.

CONCLUSION

Using XCM with or without a stent for keratinized tissue augmentation has better post-operative outcomes associated with reduced swelling, bleeding, and pain based on the QOL survey. This study provides data to support the clinical application of XCM and stents.

In Vitro Investigation of Gelatin/Polycaprolactone Nanofibers in Modulating Human Gingival Mesenchymal Stromal Cells

The aesthetic constancy and functional stability of periodontium largely depend on the presence of healthy mucogingival tissue. Soft tissue management is crucial to the success of periodontal surgery. Recently, synthetic substitute materials have been proposed to be used for soft tissue augmentation, but the tissue compatibility of these materials needs to be further investigated. This study aims to assess the in vitro responses of human gingival mesenchymal stromal cells (hG-MSCs) cultured on a Gelatin/Polycaprolactone prototype (GPP) and volume-stable collagen matrix (VSCM). hG-MSCs were cultured onto the GPP, VSCM, or plastic for 3, 7, and 14 days. The proliferation and/or viability were measured by cell counting kit-8 assay and resazurin-based toxicity assay. Cell morphology and adhesion were evaluated by microscopy. The gene expression of collagen type I, alpha1 (COL1A1), α-smooth muscle actin (α-SMA), fibroblast growth factor (FGF-2), vascular endothelial growth factor A (VEGF-A), transforming growth factor beta-1 (TGF-β1), focal adhesion kinase (FAK), integrin beta-1 (ITG-β1), and interleukin 8 (IL-8) was investigated by RT-qPCR. The levels of VEGF-A, TGF-β1, and IL-8 proteins in conditioned media were tested by ELISA. GPP improved both cell proliferation and viability compared to VSCM. The cells grown on GPP exhibited a distinct morphology and attachment performance. COL1A1, α-SMA, VEGF-A, FGF-2, and FAK were positively modulated in hG-MSCs on GPP at different investigation times. GPP increased the gene expression of TGF-β1 but had no effect on protein production. The level of ITG-β1 had no significant changes in cells seeded on GPP at 7 days. At 3 days, notable differences in VEGF-A, TGF-β1, and α-SMA expression levels were observed between cells seeded on GPP and those on VSCM. Meanwhile, GPP showed higher COL1A1 expression compared to VSCM after 14 days, whereas VSCM demonstrated a more significant upregulation in the production of IL-8. Taken together, our data suggest that GPP electrospun nanofibers have great potential as substitutes for soft tissue regeneration in successful periodontal surgery.

Stem-cell based soft tissue substitutes: Engineering of crosslinked polylysine-hyaluronic acid microspheres ladened with gingival mesenchymal stem cells for collagen tissue regeneration and angiogenesis

BACKGROUND

The aim of this study was to construct crosslinked polylysine-hyaluronic acid microspheres (pl-HAM) ladened with gingival mesenchymal stem cells (GMSCs) and explore its biologic behavior in soft tissue regeneration.

METHODS

The effects of the crosslinked pl-HAM on the biocompatibility and the recruitment of L-929 cells and GMSCs were detected in vitro. Moreover, the regeneration of subcutaneous collagen tissue, angiogenesis and the endogenous stem cells recruitment were investigated in vivo. We also detected the cell developing capability of pl-HAMs.

RESULTS

The crosslinked pl-HAMs appeared to be completely spherical-shaped particles and had good biocompatibility. L-929 cells and GMSCs grew around the pl-HAMs and increased gradually. Cell migration experiments showed that pl-HAMs combined with GMSCs could promote the migration of vascular endothelial cells significantly. Meanwhile, the green fluorescent protein-GMSCs in the pl-HAM group still remain in the soft tissue regeneration area 2 weeks after surgery. The results of in vivo studies showed that denser collagen deposition and more angiogenesis-related indicator CD31 expression in the pl-HAMs+ GMSCs + GeL group compared with the pl-HAMs + GeL group. Immunofluorescence showed that CD44, CD90, CD73 co-staining positive cells surrounded the microspheres in both pl-HAMs + GeL group and pl-HAM + GMSCs + GeL group.

CONCLUSIONS

The crosslinked pl-HAM ladened with GMSCs system could provide a suitable microenvironment for collagen tissue regeneration, angiogenesis and endogenous stem cells recruitment, which may be an alternative to autogenous soft tissue grafts for minimally invasive treatments for periodontal soft tissue defects in the future.

Patient-reported outcome measures after periodontal surgery

OBJECTIVES

The present study aimed to explore the impact of different periodontal surgical treatments on the quality of life and postoperative morbidity.

MATERIALS AND METHODS

The present study is a single-center, prospective, observational cohort trial. One hundred fifty-five patients, referred to the Periodontal Department of Bologna University who needed periodontal surgical treatment, were recruited. The self-reported perception of the postoperative course was assessed using the following anonymous questionnaires: Italian oral health impact profile (I-OHIP-14), visual analog scale (VAS) to evaluate the intensity of the pain, and 5-point Likert scale.

RESULTS

Patients reported a mean OHIP-14 total score of 9.87±8.5 (range 0-42), significantly influenced by the female sex, flap extension, and periodontal dressing. A mean VAS score of 2.96±2.39 (range 0-9) was calculated, and was found to be influenced by the presence of vertical releasing incisions and palatal flap extension. Of the 155 subjects, 40 (25.8%) patients reported bleeding as a post-surgical complication, 96 (61.9%) swelling, 105 (67.7%) eating discomfort, and 44 (28.4%) reported speech discomfort.

CONCLUSIONS

Within the limitations of the nature of the present study, periodontal surgical procedures have a low impact on patients' quality of life evaluated through the OHIP-14 and VAS pain questionnaires.

CLINICAL RELEVANCE

Periodontal surgical procedures are safe procedures, with a limited duration of postoperative discomfort as well as the incidence of complications.

Coronally advanced flap versus tunnel technique for the treatment of peri-implant soft tissue dehiscences with the connective tissue graft: A randomized, controlled clinical trial

AIM

To evaluate the efficacy of coronally advanced flap (CAF) versus tunnel technique (TUN) in covering isolated mid-facial peri-implant soft tissue dehiscences (PSTDs).

MATERIALS AND METHODS

Twenty-eight participants presenting with isolated non-molar implants exhibiting PSTDs were enrolled and randomized to receive either CAF or TUN, both with a connective tissue graft (CTG). The primary outcome of the study was the percentage of mean PSTD coverage at 12 months. Secondary endpoints included the frequency of complete PSTD coverage, changes in keratinized mucosa width (KMW) and horizontal mucosal thickness (MT), as assessed with transgingival probing, 3D optical scanning and ultrasonography, professional aesthetic evaluation and patient-reported outcome measures (PROMs).

RESULTS

At 12 months, the mean PSTD coverage of the CAF and TUN groups was 90.23% and 59.76%, respectively (p = .03). CAF-treated sites showed a substantially higher frequency of complete PSTD coverage (p = .07), together with significantly greater gain of KMW (p = .01), increase in MT (p = .02), volumetric gain (p < .01) and professional aesthetic outcomes (p = .01). Both interventions showed an improvement in patient-reported aesthetics and a reduction of the anxiety related to the appearance of the implant compared to baseline, with the CAF group obtaining significantly higher scores (p = .03 for both PROMs).

CONCLUSIONS

CAF + CTG resulted in superior PSTD coverage outcomes, greater gain in KMW and MT, and better PROMs than TUN + CTG for the treatment of isolated PSTDs (ClinicalTrials.gov NCT03498911).

Complications and treatment errors in root coverage procedures

Root coverage procedures have become very common in clinical dental practice. Even though these techniques are considered safe, the clinician may face several issues during the therapy due to their surgical nature. Some of these issues can be defined strictly as complications inherent to the procedure, whereas others are medical errors or treatment errors. This review will focus on describing treatment errors and complications that may arise during different phases of the root coverage therapeutic process and on how to prevent and manage them.

Wound healing dynamics, morbidity, and complications of palatal soft-tissue harvesting

Palatal-tissue harvesting is a routinely performed procedure in periodontal and peri-implant plastic surgery. Over the years, several surgical approaches have been attempted with the aim of obtaining autogenous soft-tissue grafts while minimizing patient morbidity, which is considered the most common drawback of palatal harvesting. At the same time, treatment errors during the procedure may increase not only postoperative discomfort or pain but also the risk of developing other complications, such as injury to the greater palatine artery, prolonged bleeding, wound/flap sloughing, necrosis, infection, and inadequate graft size or quality. This chapter described treatment errors and complications of palatal harvesting techniques, together with approaches for reducing patient morbidity and accelerating donor site wound healing. The role of biologic agents, photobiomodulation therapy, local and systemic factors, and genes implicated in palatal wound healing are also discussed.

Multiple gingival recessions associated with non-carious cervical lesions treated by partial restoration and modified coronally advanced flap with either connective tissue graft or xenogeneic acellular dermal matrix: A randomized clinical trial

BACKGROUND

This study aimed to compare a connective tissue graft (CTG) to a (porcine) xenogeneic acellular dermal matrix (XDM), both associated with modified coronally advanced flap (MCAF) and partial resin composite restoration to treat multiple combined defects (CDs).

METHODS

Seventy-eight defects in 38 patients presenting multiple combined defects, that is, gingival recession associated with non-carious cervical lesions, were treated by partial resin composite restoration (apical margin up to 1 mm of the estimated cement-enamel junction) and MCAF along with CTG or XDM. After 6 months, the groups were compared with regard to clinical, patient-centered, and esthetic outcomes.

RESULTS

CD coverage was 72.9% for CTG versus 50.7% for XDM (P < 0.001). Recession reduction was 2.3 mm for CTG versus 1.5 mm for XDM (P < 0.001). CTG resulted in a greater increase in keratinized tissue width (CTG: 0.96 mm vs. XDM: 0.3 mm, P = 0.04) and gingival thickness (CTG: 0.9 mm vs. XDM: 0.3 mm, P < 0.001). Both treatments successfully reduced dentin hypersensitivity and increased esthetics satisfaction, with no statistically significant intergroup differences. Moreover, XDM patients experienced a shorter surgery duration (CTG: 57.2 min vs. XDM: 37.4 min, P < 0.001) and less time to no pain (visual analog scale  =  0; CTG: 6.5 days vs. XDM: 3.5 days, P = 0.04).

CONCLUSION

CTG resulted in significantly greater root coverage and increased keratinized tissue width compared to XDM for treating multiple partially restored CDs. However, increased root coverage at the CTG sites was accounted for by increased probing depth compared to the XDM sites.

Effect of collagen sponge and flowable resin composite on pain management after free gingival graft harvesting: A randomized controlled clinical trial

The aim of this study was to compare the effect of the application of a flowable resin composite coating, over a collagen sponge stabilized with suture, on postoperative pain after free gingival graft harvesting. Thirty-two free gingival grafts were harvested from the palate in 32 patients, who were subsequently randomized to have only a collagen sponge stabilized with sutures applied to the palatal wound (control), or to have the collagen sponge coated with a flowable resin composite (test). Patients were observed for 14 days, and the pain level was evaluated by using a numerical rating scale. The consumption of analgesics during the postoperative period and the characteristic of the graft were also analyzed. The patients in the test group reported having experienced significantly less pain statistically than the patients in the control group throughout the study. The consumption of analgesics was lower in the test group. The dimensions of harvested grafts in the control and test groups showed no significant differences in height, width, and thickness. In conclusion, the addition of flowable resin composite coating to the hemostatic collagen sponge on the palatal wound following free gingival graft harvesting helped to minimize postoperative pain.

The efficacy of a porcine collagen matrix in keratinized mucosa width augmentation: a 10-year follow-up clinical prospective study

PURPOSE

The aim of the present study was to evaluate the long-term effectiveness of a xenogeneic collagen matrix (CM) in pre-prosthetic augmentation of the keratinized mucosa width (KMW) at implant sites.

METHODS

All of the patients with localized implant-supported rehabilitation previously treated with vestibuloplasty and KMW augmentation with a non-cross-linked porcine CM were recalled. KMW was measured clinically in an apico-coronal direction from the mucogingival junction to the mucosal margin at the prosthetic zenith of each crown. Measurements were performed clinically by means of a PCP-UNC15 periodontal probe and rounded to the nearest mm. KMW values recorded at 1 year, 5 and 10 years from the soft tissue augmentation procedure were compared using a one-way repeated-measures ANOVA with Bonferroni multiple comparison post-hoc analysis. The level of significance was set at 0.05.

RESULTS

Measurements were conducted on 13 patients. All implants were in function with no signs of biological complications. All except one implant site showed KMW ≥ 2 mm. KMW decreased significantly from 1 year (3.33 ± 1.11 mm) to 5 years (2.77 ± 0.92 mm) (p = 0.001), and finally remained stable from 5 to 10 years (3.2 ± 0.99 mm) (p = 0.607). From a visual aspect, peri-implant soft tissues were characterized by a good texture and color blending compared to the adjacent teeth, highlighting good integration of the remodeled tissues and stability of the esthetic result.

CONCLUSIONS

The use of a CM in pre-prosthetic soft tissue augmentation at implant sites has proven to be effective in obtaining and maintaining at least 2 mm of KMW around dental implants over a follow-up of 10 years.

Tunnel vs. coronally advanced flap in combination with a connective tissue graft for the treatment of multiple gingival recessions: a multi-center randomized clinical trial

OBJECTIVE

To evaluate the efficacy of the partial-thickness non-advanced tunnel technique (TUN) versus the coronally advanced flap (CAF), both combined with a connective tissue graft, in the treatment of multiple gingival recessions.

MATERIALS AND METHODS

Twenty-nine patients (83 teeth) affected by multiple gingival recessions were treated in two clinical centers with either the test (TUN) or the control (CAF) intervention combined with a connective tissue graft. Outcomes at 3 and 6 months after surgery included complete root coverage (CRC-primary outcome), mean root coverage (mRC), changes in recession depth (RD), probing pocket depth (PPD), and keratinized tissue height (KT). Root sensitivity and root coverage esthetic score (RES) were also evaluated at 6-month examination. Surgery duration, wound healing index (WHI), and patient-reported outcome measures (PROMs) were additionally considered.

RESULTS

At 6 months, CRC was observed in 80.9% and 79.5% of the teeth treated with TUN and CAF, respectively (odds ratio = 1.2; p = 0.802). No differences between groups were also observed in terms of mRC (TUN = 94.0%; CAF = 91.1%), RD and PPD reductions, root sensitivity, RES, and WHI. KT increase was significantly higher in teeth treated with TUN (Difference in Means - MD =  - 1.0 mm; p = 0.001). Surgery duration was shorter (MD =  - 19.3 min; p = 0.001), and patients reported less intra-surgical pain (MD =  - 16.4; p = 0.028) as well as postoperative morbidity in TUN compared with CAF.

CONCLUSIONS

Both surgical interventions showed a similar efficacy in terms of root coverage, albeit TUN was associated with a higher increase in KT and with a milder patient's surgical experience.

CLINICAL RELEVANCE

Both techniques have shown similar efficacy for the coverage of exposed root surfaces, although clinicians may consider TUN as less invasive.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT05122468).

Minimal invasiveness in gingival augmentation and root coverage procedures

Minimally invasive surgical procedures aim at optimal wound healing, a reduction of postoperative morbidity and, thus, at increased patient satisfaction. The present article reviews the concept of minimal invasiveness in gingival augmentation and root coverage procedures, and critically discusses the influencing factors, technical and nontechnical ones, and relates them to the underlying biological mechanisms. Furthermore, the corresponding outcomes of the respective procedures are assessed and evaluated in relation to a possible impact of a minimized surgical invasiveness on the clinical, aesthetic, and patient-related results.

Xenogeneic collagen matrix versus free gingival graft for augmenting keratinized mucosa around posterior mandibular implants: a randomized clinical trial

OBJECTIVES

To assess the clinical efficacy of xenogeneic collagen matrix (XCM) plus apically positioned flap (APF) in augmenting the keratinized mucosa (KM) width (KMW) and thickness (KMT) around posterior mandibular implants and compare it with free gingival graft (FGG) plus APF.

MATERIAL AND METHODS

Thirty patients with KMW ≤ 2 mm in the posterior mandibular implant site were randomly allocated to the FGG group (FGG plus APF) or the XCM group (XCM plus APF). Clinical assessments, including KMW and KMT, shrinkage rate of established KM, and peri-implant soft tissue health, were evaluated during a 6-month follow-up. Additionally, the esthetic outcomes and patient-reported postoperative morbidity were investigated.

RESULTS

At 6 months, the KMW measured 3.60 ± 0.79 mm in the FGG group and 3.28 ± 0.96 mm in the XCM group (p = 0.186). Both groups showed a tendency for graft contraction (FGG, 42.11%; XCM, 53.22%). The KMT measured 1.24 ± 0.34 mm in the FGG group and 0.95 ± 0.29 mm in the XCM group, with statistical difference (p = 0.002). No difference in the peri-implant soft tissue health was observed between the two groups (p > 0.05), but the esthetic outcomes were better in the XCM group (p < 0.05).

CONCLUSIONS

XCM plus APF rendered a similar clinical efficacy in augmenting KMW as that with FGG plus APF, but with higher shrinkage. XCM plus APF was inferior with respect to FGG plus APF in augmenting KMT. The esthetic outcomes were better with XCM plus APF than FGG plus APF. Clinical relevance XCM plus APF graft was inferior with respect to FGG plus APF in augmenting KMT.

TRIAL REGISTRATION

Trial registration number: ChiCTR2200058027 and date: 03/27/2022.

Tissue integration and biodegradation of soft tissue substitutes with and without compression: an experimental study in the rat

OBJECTIVES

To analyze the influence of compression on tissue integration and degradation of soft tissue substitutes.

MATERIAL AND METHODS

Six subcutaneous pouches in twenty-eight rats were prepared and boxes made of Al₂O₃ were implanted and used as carriers for soft tissue substitutes: a collagen matrix (MG), two volume-stable collagen matrices (FG/MGA), and a polycaprolactone scaffold(E). The volume-stable materials (FG/MGA/E) were further implanted with a twofold (2) and a fourfold (4) compression, created by the stacking of additional layers of the substitute materials. The samples were retrieved at 1, 2, and 12 weeks (10 groups, 3 time points, n = 5 per time point and group, overall, 150 samples). The area fraction of infiltrated fibroblasts and inflammatory cells was evaluated histologically. Due to within-subject comparisons, mixed models were conducted for the primary outcome. The level of significance was set at 5%.

RESULTS

The area fraction of fibroblasts increased in all groups over time. At 12 weeks, the densely compressed materials FG4 (1.1%), MGA4 (1.7%), and MGA2 (2.5%) obtained lower values as compared to the other groups, ranging between 4.7 (E2) and 6.5% (MG). Statistically significant differences (p ≤ 0.05) were observed between groups FG4 vs MG/FG2/E/E4 as well as between MGA4 vs MG/FG2/E/E4 and E vs MGA2.

CONCLUSIONS

Higher levels of compression led to delayed tissue integration. The effect of different compression levels was more distinct when compared to the differences between the materials.

CLINICAL RELEVANCE

All biomaterials demonstrated tissue integration and a minimal concomitant inflammatory reaction. Clinically, it might be more favorable to obtain a sufficient flap release or to reduce the material size to improve the tissue integration processes.

Long-Term Clinical Assessment of Two Modifications of Tunnel Technique in Treatment of Cairo Recession Type 1 in Lower Jaw

AIM

The aim of this study is to compare long-term results after using an MCAT (Modified Coronally Advanced Tunnel) with an SCTG (Subepithelial Connective Tissue Graft) or an MCAT with CM (Collagen Matrices) in the treatment of Cairo recession Type 1 in mandibular single-rooted teeth.

MATERIAL AND METHOD

The study encompassed 80 recessions in 18 patients for whom an MCAT was combined with CM on one side of the mandible and with an SCTG on the contralateral one. The following clinical parameters were measured: gingival recession height (GR) and width (RW), probing depth (PD), clinical attachment level (CAL), width of keratinized tissue (KT), gingival thickness (GT), and mean (MRC).

RESULTS

The MRC on the CM- and SCTG-treated sides was 55.25% and 82.35%, respectively. The SCTG side had a significantly greater improvement in MRC, GR, RW, KT, and GT compared to the CM side. The five-year results were stable relative to one-year observations.

CONCLUSIONS

Both methods of treatment enable the achievement of stable long-term clinical results. Application of subepithelial connective tissue grafts is more effective relative to clinical parameters.

PDGF-BB-enriched collagen matrix to treat multiple gingival recessions with the tunneled coronally advanced flap

BACKGROUND

With technological advancements in reconstructive periodontology, traditional protocols for the treatment of gingival recessions (GRs) can be challenged. This manuscript presents preliminary findings of a novel minimally-invasive approach for the regenerative treatment of multiple adjacent GR defects.

METHODS

Two healthy adults were treated as part of this study. Multiple adjacent GRs in both subjects (1 in the mandible, and 1 in the maxilla) were treated employing a tunneled coronally advanced flap (TCAF) design, with the application of a cross-linked collagen matrix (CCM) that was enriched with recombinant human platelet-derived growth factor-BB (PDGF-BB) that was also applied on the prepared root surfaces. Clinical, ultrasonographic, esthetic, and patient-reported outcomes were observed at approximately 6- and 18-month time points.

RESULTS

All sites healed uneventfully after the treatments. Complete root coverage was achieved and maintained throughout the follow-up observations, from 6 to 18 months. Patients reported minimal discomfort and reduction of dentinal hypersensitivity at the augmented sites. The areas augmented with CCM + PDGF-BB revealed an increased soft tissue thickness relative to baseline (pretreatment) measures, as well as reduction in the level of the facial bone dehiscences.

CONCLUSION

This article describes the success of two cases of a novel minimally invasive regenerative approach for the treatment of multiple adjacent GR defects by the TCAF, using a CCM loaded with PDGF-BB. This approach offers potential as a minimally-invasive method to repair multiple adjacent GRs.

Recombinant human platelet-derived growth factor improves root coverage of a collagen matrix for multiple adjacent gingival recessions: A triple-blinded, randomized, placebo-controlled trial

AIM

To evaluate the efficacy of recombinant human platelet-derived growth factor (rhPDGF)-BB combined with a cross-linked collagen matrix (CCM) for the treatment of multiple adjacent gingival recession type 1 defects (MAGRs) in combination with the coronally advanced flap (CAF).

MATERIALS AND METHODS

Thirty patients were enrolled in this triple-blind, randomized, placebo-controlled trial and treated with either CAF + CCM + rhPDGF, or CAF + CCM + saline. The primary outcome was mean root coverage (mRC) at 6 months. Complete root coverage, gain in gingival thickness (GT), keratinized tissue width, volumetric and ultrasonographic changes, and patient-reported outcome measures were also assessed. Mixed-modelling regression analyses were used for statistical comparisons.

RESULTS

At 6 months, the mRC of the CCM + rhPDGF and CCM alone groups were 88.25% and 77.72%, respectively (p = .02). A significant gain in GT was consistently observed for both treatment arms, and more so for the patients receiving the matrix containing rhPDGF through time (0.51 vs. 0.80 mm, on average, p = .01). The rhPDGF + CCM treated patients presented greater volume gain, higher soft tissue thickness, and a superior aesthetic score.

CONCLUSION

rhPDGF enhances the clinical, volumetric, and aesthetic outcomes of MAGRs above the results achieved with CAF + CCM alone (ClinicalTrials.gov NCT04462237).

Treatment of multiple adjacent RT 1 gingival recessions with the modified coronally advanced tunnel (MCAT) technique and a collagen matrix or palatal connective tissue graft: 9-year results of a split-mouth randomized clinical trial

OBJECTIVES

To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with either a collagen matrix CM or a connective tissue graft (CTG).

MATERIAL AND METHODS

Sixteen of the original 22 subjects included in a randomized, controlled split-mouth clinical trial were available for the 9-year follow-up (114 sites). Recessions were randomly treated by means of MCAT + CM (test) or MCAT + CTG (control). Complete root coverage (CRC), mean root coverage (MRC), gingival recession depth (GRD), probing pocket depth (PD), keratinized tissue width (KTW), and thickness (KGT) were compared with baseline values and with the 12-month results.

RESULTS

After 9 years, CRC was observed in 2 patients, one in each group. At 9 years, MRC was 23.0 ± 44.5% in the test and 39.7 ± 35.1% in the control group (p = 0.179). The MRC reduction compared to 12 months was - 50.1 ± 47.0% and - 48.3 ± 37.7%, respectively. The upper jaw obtained 31.92 ± 43.0% of MRC for the test and 51.1 ± 27.8% for the control group (p = 0.111) compared to the lower jaw with 8.3 ± 46.9% and 20.7 ± 40.3%. KTW and KGT increased for both CM and CTG together from 2.0 ± 0.7 to 3.1 ± 1.0 mm (< 0.0001). There were no statistically significant changes in PD.

CONCLUSION

The present results indicate that (a) treatment of MAGR using MCAT in conjunction with either CM or CTG is likely to show a relapse over a period of 9 years, and (b) the outcomes obtained in maxillary areas seem to be more stable compared to the mandibular ones.

CLINICAL RELEVANCE

The mean root coverage at 12 months could not be fully maintained over 9 years. On a long-term basis, the results seem to be less stable in the mandible as compared to maxillary areas.

A New Matrix for Soft Tissue Management

Gingival recession is a mucogingival defect defined as the apical shifting of the gingival margin in relation to the CEJ. The use of connective tissue autografts allows for the obtention of very satisfactory results but is associated with undoubted disadvantages. The aim of the present work is to carry out a systematic review of the literature using a meta-analysis to investigate the clinical efficacy of xenogeneic collagen matrix (XCM) in the treatment of gingival recessions. This revision was carried out strictly following the guidelines published in the Cochrane Handbook. Thus, a meta-analysis was performed to calculate relative risks and standardized mean differences for each of the variables considered. The results of the meta-analysis show that CAF + CTG was statistically better than CAF + XCM in almost all the variables analyzed: complete root coverage (RR 0.46), mean root coverage (SMD −0.89), recession reduction (SMD −0.98), clinical attachment level (SMD −0.63) and gingival thickness (SMD −1.68). Meanwhile, CAF + XCM was slightly better than CAF alone in regard to: mean root coverage (SMD 0.51), recession reduction (SMD 0.47) and gingival thickness (SMD 0.56). It is possible to conclude that CAF + CTG still remains the gold standard in radicular coverage.

Soft tissue phenotype modification predicts gingival margin long-term (10-year) stability: Longitudinal analysis of six randomized clinical trials

Aim

To assess the prognostic value of soft tissue phenotype modification following root coverage procedures for predicting the long‐term (10‐year) behaviour of the gingival margin.

Materials and Methods

Participants from six randomized clinical trials on root coverage procedures at the University of Michigan were re‐invited for a longitudinal evaluation. Clinical measurements were obtained by two calibrated examiners. A data‐driven approach to model selection with Akaike information criterion (AIC) was carried out via multilevel regression analyses and partial regression plotting for changes in the level of the gingival margin over time and interactions with the early (6‐month) results of soft tissue phenotypic modification.

Results

One‐hundred and fifty‐seven treated sites in 83 patients were re‐assessed at the long‐term recall. AIC‐driven model selection and regression analyses demonstrated that 6‐month keratinized tissue width (KTW) and gingival thickness (GT) influenced the trajectory of the gingival margin similarly in a concave manner; however, GT was the driving determinant that predicted significantly less relapse in the treatments, with stability of the treated gingival margin obtained beyond values of 1.46 mm.

Conclusions

Among a compliant patient cohort, irrespective of the rendered therapy, the presence of at least 1.5 mm KTW and 1.46 mm GT was correlated with the long‐term stability of the gingival margin.

Comparison between connective tissue graft and xenogeneic acellular dermal matrix to treat single gingival recession: A data reanalysis of randomized clinical trials

OBJECTIVES

There are few studies comparing xenogeneic acellular dermal matrixes (XDMs) with connective tissue graft (CTG) to treat single gingival recession (GR). The present study involved a reanalysis of previous studies and comparison of CTG or XDM to treat single RT1/GR.

MATERIALS AND METHODS

Fifty patients from three previous randomized clinical trials treated either by CTG (n = 25) or XDM (n = 25) were evaluated after 6-month. Clinical, patient-centered, and esthetic parameters were assessed. Pearson's correlation and regression analyses were also performed.

RESULTS

Greater recession reduction (RecRed), percentage of root coverage (%RC), and complete root coverage (CRC) were observed in the CTG group (p ≤ 0.02). Gingival thickness (GT) and keratinized tissue width (KTW) gains were higher in the CTG group. The CTG group showed better esthetic at 6-month. Logistic analyses reported that GT([OR] = 1.647³ ) and papilla height (PH) (OR = 8.20) are predictors of CRC. GT*XDM interaction was a negative predictor of CRC (OR = 7.105^-5 ). GT at baseline acted as a predictor of RecRed in both groups (p = 0.03). The XDM graft impacted RecRed and %RC negatively. Baseline PH was a predictor of %RC for both grafts.

CONCLUSION

CTG was superior for treating RT1/GR, providing better root coverage outcomes and tissue gains over time. GT, PH, and graft type were classified as predictors of CRC.

CLINICAL SIGNIFICANCE

CTG presented better outcomes to treat single RT1 gingival recession when compared to the XDM.

Effectiveness of surgical root coverage on dentin hypersensitivity: A systematic review and meta-analysis

AIM

To assess the effect of surgical root coverage (RC) on dentin hypersensitivity (DH) associated with gingival recession.

MATERIALS AND METHODS

Two independent reviewers conducted electronic literature searches in MEDLINE (PubMed), EMBASE, Cochrane Library, Web Of Science, Dentistry & Oral Sciences Source, ScienceDirect, and ClinicalTrials.gov databases as well as a manual search to identify eligible clinical studies from January 2000 to March 2022. Randomized controlled trials (RCTs) comparing two surgical RC techniques or a surgical RC technique with or without adjuvant were included. Meta-analyses were performed on data provided by RCTs.

RESULTS

Thirteen RCTs with a total of 701 patients (1086 recessions) were included. The percentage of DH suppression was 70.8% (95% confidence interval [CI] [64.4-76.6]; I²  = 39.2% [3.5-61.8], Q-test = 0.02) after surgical RC. Recession reduction and percentage of RC were both statistically significantly associated with DH suppression (estimate = 0.66 [0.10-1.23], p = .022, R²  = 14.45% and estimate = 0.04 [0.01-0.08], p = .012, R²  = 29.54%, respectively). Coronally advanced flap (CAF) + connective tissue graft showed results statistically more effective than CAF + xenogeneic collagen matrix in DH suppression (73.3% [65.6-79.8] and 61.4% [51.7-70.3], respectively; p = .048).

CONCLUSIONS

Success of surgical RC is associated with DH suppression.

Enamel Matrix Derivatives for Periodontal Regeneration: Recent Developments and Future Perspectives

In the era of the growing population, the demand for dental care is increasing at a fast pace for both older and younger people. One of the dental diseases that has attracted significant research is periodontitis. Periodontal therapy aims to regenerate tissues that are injured by periodontal disease. During recent decades, various pioneering strategies and products have been introduced for restoring or regeneration of periodontal deficiencies. One of these involves the regeneration of tissues under guidance using enamel matrix derivatives (EMDs) or combinations of these. EMDs are mainly comprised of amelogenins, which is one of the most common biological agents used in periodontics. Multiple studies have been reported regarding the role of EMD in periodontal tissue regeneration; however, the extensive mechanism remains elusive. The EMDs could promote periodontal regeneration mainly through inducing periodontal attachment during tooth formation. EMD mimics biological processes that occur during periodontal tissue growth. During root development, enamel matrix proteins are formed on the root surface by Hertwig's epithelial root sheath cells, initiating the process of cementogenesis. This article reviews the challenges and recent advances in preclinical and clinical applications of EMDs in periodontal regeneration. Moreover, we discuss the current evidence on the mechanisms of action of EMDs in the regeneration of periodontal tissues.

mTOR Signaling in the Regulation of CD4+ T Cell Subsets in Periodontal Diseases

Periodontal disease results from the inflammatory infiltration by the microbial community which is marked through tooth mobility and alveolar bone resorption. The inflammation in periodontal disease is mediated by CD4⁺ T cells through cytokine secretion and osteoclastogenetic activity. Historically, the inflammatory model in periodontal disease is described through disruption of the balance between two subsets of T helper cells which are T-helper type 1 (Th1) and T-helper type 2 (Th2). However, more and more studies have found that apart from subsets of helper T cells, regulatory T-cells and Th17 cells are also involved in the pathogenesis of periodontal diseases. Growing evidence proves that helper T cells differentiation, activation, and subset determination are under the strong impact of mTOR signaling. mTOR signaling could promote Th1 and Th17 cell differentiation and inhibit Treg commitment through different mTOR complexes, therefore we anticipate a regulation effect of mTOR signaling on periodontal diseases by regulating CD4⁺ T cell subsets. This review aims to integrate the topical researches about the role of different types of Th cells in the pathogenesis of periodontal diseases, as well as the regulation of mTOR signaling in the specification and selection of Th cell commitment.

Cell Therapy Based on Gingiva-Derived Mesenchymal Stem Cells Seeded in a Xenogeneic Collagen Matrix for Root Coverage of RT1 Gingival Lesions: An In Vivo Experimental Study

(1) Background: To investigate the effect of a xenogeneic collagen matrix (CMX) seeded with autologous gingiva-derived mesenchymal cells (GMSCs) when combined with a coronally advanced flap (CAF) in the treatment of localized gingival recession type 1 (RT1). (2) Methods: Dehiscence-type defects were created in seven dogs. GMSCs were isolated, transfected with a vector carrying green fluorescent protein (GFP) and expanded. Once chronified, the defects were randomly treated with (1) CAF plus the combination of CMX and GFP⁺ GMSCs, (2) CAF plus CMX with autologous fibroblasts, (3) CAF plus CMX and (4) CAF alone. Histological and clinical outcomes at 2- and 6-week healing periods were analyzed and compared among groups. (3) Results: Histologically, the addition of autologous cells to the CMX resulted in reduced inflammation and a variable degree of new cementum/bone formation. CMX plus GMSCs resulted in greater mean recession reduction (1.42; SD = 1.88 mm) and percentage of teeth with recession reduction of ≥2 mm (57%) when compared to the other groups, although these differences were not statistically significant. (4) Conclusions: The histometric and clinical results indicated a positive trend favouring the combination of CMX and GMSCs with the CAF when compared to the groups without cells, although these differences were not statistically significant.

Modified tunneling technique for root coverage of anterior mandible using minimal soft tissue harvesting and volume-stable collagen matrix: a retrospective study

Purpose

In this study, we aimed to evaluate the clinical validity of the modified tunneling technique using minimal soft tissue harvesting and volume-stable collagen matrix in the anterior mandible.

Methods

In total, 27 anterior mandibular teeth and palatal donor sites in 17 patients with ≥1 mm of gingival recession (GR) were analyzed before and after root coverage. For the recipient sites, vertical vestibular incisions were made in the interdental area and a subperiosteal tunnel was created with an elevator. After both sides of the marginal gingiva were tied to one another, a prepared connective tissue graft and volume-stable collagen matrix were inserted through the vestibular vertical incision and were fixed with resorbable suture material. The root coverage results of the recipient site were measured at baseline (T₀), 3 weeks (T₃), 12 weeks (T₁₂), and the latest visit (T_l). For palatal donor sites, a free gingival graft from a pre-decided area avoiding the main trunk of the greater palatine artery was harvested using a prefabricated surgical template at a depth of 2 mm after de-epithelization using a rotating bur. In each patient, the clinical and volumetric changes at the donor sites between T₀ and T₃ were measured.

Results

During an average follow-up of 14.5 months, teeth with denuded root lengths of 1–3 mm (n=12), 3–6 mm (n=11), and >6 mm (n=2) achieved root coverage of 97.01%±7.65%, 86.70%±5.66%, and 82.53%±1.39%, respectively. Miller classification I (n=12), II (n=10), and III (n=3) teeth showed mean coverage rates of 97.01%±7.65%, 86.91%±5.90%, and 83.19%±1.62%, respectively. At the donor sites, an average defect depth of 1.41 mm (70.5%) recovered in 3 weeks, and the wounds were epithelized completely in all cases.

Conclusions

The modified tunneling technique in this study is a promising treatment modality for overcoming GR in the anterior mandible.