Competence of allogenic demineralized tooth matrix in socket seal surgery for alveolar ridge preservation: a randomized control clinical trial.

OBJECTIVES: To assess and compare the clinical, radiological, and histological outcomes of socket seal surgery between two protocols: deproteinized demineralized tooth matrix (dpDTM) and freeze-dried bone allograft (FDBA) each covered with a free gingival graft. MATERIALS AND METHODS: Twenty extraction sockets in the anterior or premolar region were randomly allocated to either the dpDTM or FDBA protocol (n = 10 per group). Measurements of the alveolar ridge changes were obtained using an intraoral scanner and cone-beam computed tomography at 3 months post-operation. Three-month post surgery, the dental implant was installed (n = 5 per group), bone biopsies were obtained for histomorphometrical and micro-computed tomography analyses. Implant stability quotients (ISQs) were determined and compared at 3 months post-implant. RESULTS: Lower significant reductions in buccal alveolar ridge height and hard tissue volume were observed in dpDTM group compared to FDBA group at 3 months (0.25 ± 0.35 mm vs. 1.60 ± 0.66 mm [p = .000] and 9.64 ± 15.39% mm3 vs. 31.45 ± 18.11% mm3 [p = .010], respectively). At the same time, lower soft tissue volume reduction was detected in the dpDTM group compared to FDBA group (4.21 ± 5.25% mm3 vs. 5.25 ± 5.79% mm3). No statistically significant difference in the percentage of mineralized tissue formation was found between dpDTM group (53.39 ± 11.16%) and FDBA group (49.90 ± 3.27%). Even though the ISQ in the dpDTM group showed a higher value than the FDBA group at 3 months post-implant, the results were without statistical significance. CONCLUSIONS: Alveolar ridge preservation using dpDTM is an efficacious procedure for providing the conditions for the development of functional and esthetic implants.

Effect of hyaluronic acid on palatal wound healing: A systematic review.

OBJECTIVES: To evaluate the efficacy of topically applied hyaluronic acid on wound healing (patient-reported outcomes and clinical healing) after a palatal autogenous gingival graft is harvested. MATERIALS AND METHODS: A systematic search was performed in April 2024 in eleven electronic databases. Two investigators independently screened the references for inclusion. Outcomes of interest included postoperative pain, analgesic consumption, complete epithelialization, and color match, which were synthesized using narrative synthesis. RESULTS: A total of 535 results were identified and eight articles were included in the systematic review. Hyaluronic acid use on the palatal donor site had a better response to healing and wound size compared to the control sites with no agent applied. Hyaluronic acid demonstrated a positive effect in the form of complete epithelialization, and color match, with improved patient-reported outcomes such as post-operative pain. CONCLUSION: Within the limitations of this systematic review, it can be concluded that hyaluronic acid shows a strong potential to improve patient-reported outcomes and clinical wound healing at the graft donor site on the palate. Future studies are required to clarify the optimal concentration, frequency of application, and synergistic effect when HA is combined with other interventions. CLINICAL RELEVANCE: Within the limitations of this systematic review, it can be concluded that hyaluronic acid shows a strong potential to improve patient-reported outcomes and clinical wound healing at the graft donor site on the palate. Future studies are required to clarify the optimal concentration, frequency of application, and synergistic effect when HA is combined with other interventions.

Effect of botulinum toxin-A injection applied to the mentalis muscle on free gingival graft operation: A retrospective study.

OBJECTIVE: The purpose of this retrospective study was to investigate the effects of Botulinum Toxin-A (BTX-A) injection into the mentalis muscle on the free gingival graft (FGG). MATERIALS AND METHODS: Forty patients with keratinized gingiva insufficiency and Cairo's RT 2 gingival recession (formerly classified as Miller class III) in their mandibular central incisors were randomly divided into two groups: FGG and FGG + BTX. Plaque index (PI), gingival index (GI), probing pocket depth (PPD), keratinized gingiva width (KGW), attached gingiva width (AGW), clinical attachment level (CAL), gingival thickness (GT), gingival recession amount (GRA), gingival recession width (GRW), and root closure percentage (RCP%) parameters were measured at baseline and at first, third, and sixth months after the operation. RESULTS: There was no difference in PI, GI, and PPD levels in both groups (p > 0.05). While the change in GT and RCP% levels were found to be statistically significantly higher at FGG + BTX group than FGG group, the change in GRW and CAL levels were statistically significantly lower (p < 0.05). CONCLUSION: The findings of this study indicate that BTX-A injection applied to the mentalis muscle after FGG operation may have positive effects in terms of KGW, AGW, GT, RCP%, GRW, and CAL parameters. CLINICAL SIGNIFICANCE: As a result of the fact that BTX-A injection into the mentalis muscle contributed to the nutrition and immobility of FGG, positive developments were obtained in terms of clinical periodontal parameters. BTX-A injection into the mentalis muscle may be an alternative method that increases the success rate of Cairo's RT 2 gingival recession.

A modified geometric technique to increase peri-implant keratinized mucosa.

OBJECTIVE: The free gingival graft (FGG) has been identified as the most effective method for increasing keratinized mucosa width (KMW). However, the challenge emerges in cases of extensive keratinized mucosa deficiency, where efficient utilization of the patient's limited keratinized tissue to achieve optimal results is crucial. This article introduces a modified geometric technique to address this clinical issue. CLINICAL CONSIDERATIONS: Utilizing geometric principles, the modified technique involves dividing the rectangular graft into two triangular or trapezoidal sections, which are then reassembled to form an approximate diamond shape. Through strategic cut and splice, the graft is reshaped to suit the recipient site. CONCLUSION: Preliminary observations in cases employing the modified geometric technique have increased the KMW around implants. This method enhances graft utilization and offers a viable clinical option for surgical plans aimed at widening keratinized mucosa in instances of large-area KMW deficiency. CLINICAL SIGNIFICANCE: This article proposed a modified method to increase KMW, which may be an optimal choice for patients with insufficient KMW in large area, avoiding the waste of limited graft, decreasing patient morbidity, and effectively widening keratinized mucosa.

A novel "microscrew with tie-down sutures" technique for FGG anchorage: A case report.

The most difficult and time-consuming step in the free gingival graft (FGG) for keratinized mucosa augmentation is the compression suture anchoring the FGG to the periosteum. In this article, a novel "microscrew with tie-down sutures" technique was proposed to anchor the FGG to the recipient site without the traditional trans-periosteum suture. This patient's keratinized mucosa width (KMW) around the healing abutments of teeth #29 and #30 was less than 1 mm. After an apically positioned flap (AFP) was prepared, two microscrews were placed at the buccal plate of the alveolar ridge bone, which is the coronal margin of the AFP. Then, the sutures winded between the microscrews and the healing abutments to anchor the FGG. In conclusion, the "microscrew with tie-down sutures" technique offers a feasible and simple alternative for the trans-periosteum compression suture, particularly in situations when the periosteum is fragile, thin, or injured.

[Histopathological characteristics of peri-implant soft tissue in reconstructed jaws with vascularized bone flaps].

OBJECTIVE: To analyze the histopathological characteristics of peri-implant soft tissue in reconstructed jaws and the changes after keratinized mucosa augmentation (KMA) with free gingival graft (FGG). METHODS: Twenty patients were enrolled in this study. Five patients of them, who were periodontal and systemic healthy and referred for crown lengthening before restoration with healthy keratinized gingiva collected were enrolled as healthy controls. 15 patients of them were with fibula or iliac bone flaps jaw reconstruction (10 with fibula flap and 5 with iliac flap), who were referred to FGG and implant exposures before restoration. Soft tissue was collected before FGG in reconstructed jaws, and in 5 patients (3 with fibula flap and 2 with iliac flap) 8 weeks after FGG if a second surgery was conducted. Histological analysis with hematoxylin-eosin stain and immunological analysis to interlukin-1 (IL-1), interlukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were performed. RESULTS: Thickness from the bottom of stratum basale to the top of stratum granulosum and thickness of keratinized layer in reconstructed jaws were significantly lower compared with that of natural healthy keratinized gingiva [0.27 (0.20, 0.30) mm vs. 0.36 (0.35, 0.47) mm, P<0.05; 16.49 (14.90, 23.37) µm vs. 26.37 (24.12, 31.53) µm, P<0.05]. In the reconstructed area, thickness from the bottom of stratum basale to the top of stratum granulosum increased after KMA with FGG [0.19 (0.16, 0.25) mm vs. 0.38 (0.25, 0.39) mm, P=0.059] and the thickness of keratinized layer significantly increased after KMA with FGG [16.42 (14.16, 22.35) µm vs. 28.57 (27.16, 29.14) µm, P<0.05], which was similar to that in the control group. Furthermore, the number of positive cells of IL-1, IL-6 and TNF-α significantly increased after KMA [0.67 (0.17, 8.93) vs. 11.00 (9.16, 18.00); 13.00 (8.50, 14.14) vs. 21.89 (15.00, 28.12); 0.22 (0.04, 0.63) vs. 2.83 (1.68, 5.00), respectively, P<0.05] as well as the average optical density value [0.15 (0.14, 0.17) vs. 0.18 (0.17, 0.21); 0.28 (0.26, 0.33) vs. 0.36 (0.33, 0.37); 0.23 (0.22, 0.29) vs. 0.30 (0.28, 0.42), respectively, P<0.05], which was similar to that in the healthy keratinized gingiva. CONCLUSION: The lack of rete pegs and inflammatory factors were common in soft tissue with jaw reconstruction. FGG can improve the quality of the epithelium and may improve the stability of the mucosa around implants.

Revisiting failures in mucogingival surgery.

Failures of soft tissue grafting are relatively common and can be stressful when encountered for both the clinicians and patients. Soft tissue grafting has predictable success most of the time when proper selection and implementation of surgical procedure is done. This case report describes management of soft-tissue surgery failure after multiple mucogingival grafting for enhancing the soft-tissue quality, quantity, and aesthetic outcomes. Augmentation by free gingival graft using periodontal microsurgical principle resulted complete coverage of the defect suggesting that careful treatment planning, immaculate execution by skillful technique definitely helped to achieve a successful result. Simultaneous use of photobiomodulation (PBM) helped in faster and better healing of the grafted area.

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.

Pleiotropic effect of intramucosal injection of FTY720 on angiogenesis and tissue healing after free gingival graft surgery: a comparative experimental study in rabbits.

OBJECTIVES: Free gingival graft surgery is the gold standard for increasing the size of keratinized tissue. Blood supply in the recipient site is critical for healing. Therefore, in this study, the effect of FTY720 on angiogenesis, healing, and scar tissue presence following free gingival graft surgery is investigated. MATERIALS AND METHODS: Surgeries were performed on 10 New Zealand white rabbits. Rabbits were randomly assigned to two groups. In the experimental group, immediately after surgery, 2 and 4 days later, FTY-720 was injected into the tissue surrounding the recipient site. In the control group, the same frequency of placebo vehicle was injected. After 30 days, tissue samples were assessed histologically and histomorphometrically. RESULTS: The blood vessel count (P < 0.000) and rete ridge formation (P < 0.05) in the experimental group were significantly higher, while the epithelial thickness was lower in this group (P < 0.000). There was no significant difference in the percentage of regions occupied by collagen fibres between the groups (P = 0.987). Furthermore, a significant and negative relationship between epithelial thickness and blood vessel count was shown (Pearson correlation coefficient = - 0.917). CONCLUSIONS: The findings indicate that the angiogenic effects of FTY-720 in the recipient site of free gingival graft can be employed to promote tissue healing and reduce scar tissue presence. CLINICAL RELEVANCE: A significant decrease in epithelial thickness and increase in angiogenesis as well as rete ridge formation score in the FTY-720 group were shown, which can be translated into improved tissue healing and less presence of scar tissue.

Pre-operative, chair-side Zn-containing surgical stents affect morbidity and wound healing after free gingival graft harvesting: a randomized clinical trial.

OBJECTIVE: To compare a pre-operatively, chair-side made, zinc-containing surgical stent (ZN) and suturing of a gelatin-based hemostatic agent (HA) on palatal wound healing and patient morbidity after free gingival graft surgery (FGG). MATERIALS AND METHODS: Sixty patients requiring FGG were randomly divided into two groups to receive either a ZN or a sterile HA sutured on the surgical area. Patients were evaluated at 1st, 3rd, 7th, 14th, 28th, and 56th days following surgery. Overall surgical time, donor site surgical time, postoperative pain (PP), delayed bleeding (DB), changes in dietary habits (DH), burning sensation (BS), completion of re-epithelialization (CE), and patients' discomfort (PD) were evaluated. RESULTS: Donor site surgical time, PP, DB, DH, BS were statistically significantly lower in the ZN group together with faster completion of re-epithelialization compared to the HA group. CONCLUSION: Pre-operatively, chair-side made, zinc-containing surgical stents provided significant benefits for wound healing parameters and patients' postoperative morbidity after FGG harvesting. CLINICAL RELEVANCE: The results show that using Zn-containing palatal stent after free gingival graft surgery significantly reduces pain and patient morbidity during the postoperative period.

Postoperative local interventions for the palate as a gingival graft donor area: a scoping review.

OBJECTIVE: This scoping review aimed to systematically identify evidence-based interventions to stimulate healing or protect the harvested palate of patients undergoing gingival grafting. MATERIAL AND METHODS: The study followed guidelines from the Joanna Briggs Institute and PRISMA-ScR (protocol available at osf.io/zhafn). PubMed, Embase, and seven other databases were searched on November 2022, with additional monitoring until April 2023. The inclusion criteria focused on studies evaluating outcomes related to the donor area (palate) and interventions for healing or protecting it, regardless of publication year and language. Data from the included publications was extracted and presented through narrative text, tables, and figures. RESULTS: Eighty-one studies (including 64 clinical trials, four case series, five theses, and eight systematic reviews) and 37 clinical trial records were included. The number of studies on this topic has significantly increased, reflecting a growing interest in the field. Thirty-six interventions with published results and 12 interventions with unpublished results from clinical trial registers were identified. Some promising interventions that showed potential for improving patient-reported outcomes include cyanoacrylate adhesive, platelet-rich fibrin (PRF), and the combination of palatal stents and healing agents. CONCLUSIONS: Thirty-six interventions with published results were identified for postoperative use on the harvested palate, showing varying levels of evidence and conflicting effectiveness for specific outcomes. CLINICAL RELEVANCE: Postoperative discomfort and pain in the palate are commonly experienced by patients undergoing grafting procedures using this region as the donor area. Awareness of the available options and their levels of evidence is crucial for informed decision-making.

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.

Clinical evaluation of different alveolar ridge preservation techniques after tooth extraction: a randomized clinical trial.

OBJECTIVE: The aim of the present randomized controlled trial (RCT) was to evaluate the efficacy of different alveolar ridge preservation (ARP) techniques on dimensional alterations after tooth extraction, based on clinical measurements. BACKGROUND: Alveolar ridge preservation (ARP) is a common procedure in every day clinical practice, when dental implants are involved in treatment planning. In ARP procedures, a bone grafting material is combined with a socket sealing (SS) material in order to compensate the alveolar ridge dimensional alterations after tooth extraction. Xenograft and allograft are the most frequently used bone grafts in ARP, while free gingival graft (FGG), collagen membrane, and collagen sponge (CS) usually applied as SS materials. The evidence comparing xenograft and allograft directly in ARP procedure is scarce. In addition, FGG is usually combined with xenograft as SS material, while the evidence combing allograft with FGG is absent. Moreover, CS could probably be an alternative choice in ARP as SS material, since it has been used in previous studies but more clinical trials are required to evaluate its effectiveness. MATERIALS AND METHODS: Forty-one patients were randomly assigned in four treatment groups: (A) freeze-dried bone allograft (FDBA) covered with collagen sponge (CS), (B) FDBA covered with free gingival graft (FGG), (C) demineralized bovine bone mineral xenograft (DBBM) covered with FGG, and (D) FGG alone. Clinical measurements were performed immediately after tooth extraction and 4 months later. The related outcomes pertained to both vertical and horizontal assessment of bone loss. RESULTS: Overall, groups A, B, and C presented significantly less vertical and horizontal bone resorption compared to group D. No statistically significant difference was observed between allograft and xenograft, except for the vertical bone resorption at the buccal central site, where xenograft showed marginally statistically significantly reduced bone loss compared to allograft (group C vs group B: adjusted ß coef: 1.07 mm; 95%CI: 0.01, 2.10; p = 0.05). No significant differences were observed in hard tissue dimensions when CS and FGG were applied over FDBA. CONCLUSIONS: No differences between FDBA and DBBM could practically be confirmed. In addition, CS and FGG were equally effective socket sealing materials when combined with FDBA, regarding bone resorption. More RCTs are needed to compare the histological differences between FDBA and DBBM and the effect of CS and FGG on soft tissue dimensional changes. CLINICAL RELEVANCE: Xenograft and allograft were equally efficient in ARP 4 months after tooth extraction in horizontal level. Xenograft maintained the mid-buccal site of the socket marginally better than the allograft, in vertical level. FGG and CS were equally efficient as SS materials regarding the hard tissue dimensional alterations. TRIAL REGISTRATION: Clinical trial registration Number: NCT04934813 (clinicaltrials.gov).

Electrophoretically Co-Deposited Collagen-Lactoferrin Membranes with Enhanced Pro-Regenerative Properties for Oral Soft Tissue Regeneration.

The quality of soft tissue defect regeneration after dental surgeries largely determines their final success. Collagen membranes have been proposed for the healing of such defects, but in some cases, they do not guarantee a sufficient volume of the regenerated tissue and vascularization. For this purpose, lactoferrin, a protein with natural pro-regenerative, anti-inflammatory, and pro-angiogenic activity, can be added to collagen. In this article, we used a semipermeable barrier-assisted electrophoretic deposition (SBA-EPD) method for the production of collagen-lactoferrin membranes. The membrane structure was studied by SEM, and its mechanical properties were shown. The lactoferrin release kinetics were shown by ELISA within 75 h. When tested in vitro, we demonstrated that the collagen-lactoferrin membranes significantly increased the proliferation of keratinocytes (HaCaT) and fibroblasts (977hTERT) compared to blank collagen membranes. In vivo, on the vestibuloplasty and free gingival graft harvesting models, we showed that collagen-lactoferrin membranes decreased the wound inflammation and increased the healing rates and regeneration quality. In some parameters, collagen-lactoferrin membranes outperformed not only blank collagen membranes, but also the commercial membrane Mucograft®. Thus, we proved that collagen-lactoferrin membranes produced by the SBA-EPD method may be a valuable alternative to commercially used membranes for soft tissue regeneration in the oral cavity.

Submerged Technique of Partially De-Epithelialized Free Gingival Grafts for Gingival Phenotype Modification in the Maxillary Anterior Region: A Case Report of a 34-Year Follow-up.

A coronally advanced flap combined with a subepithelial connective tissue graft is considered the gold standard for achieving root coverage on exposed root surfaces. Nevertheless, challenges arise when this technique is applied to multiple teeth and when the palatal soft tissue is very thin. Several surgical modifications have been reported to simultaneously achieve both single or multiple root coverage and widening of the keratinized gingiva. In this context, there have been no reported cases utilizing the submerged technique with partially de-epithelialized free gingival grafts. We intend to introduce a submerged technique involving partially de-epithelialized free gingival grafts for the modification of soft tissue phenotypes in the maxillary anterior region.

Oral Lichenoid Lesion following Dental Implant Placement and Successful Management with Free Gingival Graft: A Case Report with 10-Year Follow-Up.

Titanium and metal alloys are widely used in implants, crowns, and bridges in implant dentistry owing to their biocompatibility. In this case report of a 45-year-old female patient, multiple implants were placed in five different sextants at different time points. Notably, oral lichenoid lesions (OLL) occurred in three sextants following implant placement, strongly suggesting that the dental implants or prostheses were the causative factors for OLL. The lesion was of the reticular type with erythematous surroundings and was symptomatic. Although several conservative treatments, including repeated topical application of corticosteroids, were repeatedly continued, no discernible improvement or alleviation of symptoms was observed. Consequently, surgical excision and replacement of the lesion with a free gingival graft (FGG) harvested from the palatal soft tissue were performed. No clinical symptoms or recurrence of lesions were observed during 10 years of follow-up post-FGG.

[A modified technique for expanding the attached keratinized gingiva zone using a free gingival graft "Danilov`s medallions"]. / Modifitsirovannaya metodika rasshireniya zony prikreplennoi keratinizirovannoi desny s pomoshch'yu svobodnogo desnevogo transplantata «medal'ony po Danilovu¼.

On a clinical example a modified technique for increasing the width of the attached keratinized gingiva zone is presented by taking medallions of a free gingival graft 1.5-2 mm thick from the hard palate using 5 mm mucotomes and transplanting them into the gum defect zones with a simultaneous vestibular deepening in the lateral regions of the jaws. This technology has been tested over a 5-year period with long-term clinical results.

Efficacy of soft tissue substitutes, in comparison with autogenous grafts, in surgical procedures aiming to increase the peri-implant keratinized mucosa: A systematic review.

OBJECTIVES: The aim of this systematic review was to evaluate the efficacy of soft tissue substitutes compared to autogenous gingival grafts in surgical procedures aimed at increasing the width of keratinized mucosa (KM) around dental implants. MATERIALS AND METHODS: Two focused questions were developed: PICOS #1) "What is the efficacy of surgical procedures using soft tissue substitutes, as compared to autogenous grafts, to increase the amount of peri-implant keratinized mucosa, in randomized clinical trials (RCTs) and controlled clinical trials (CCTs)?"; and PICOS #2) "What is the effectiveness of soft tissue substitutes to increase the amount of peri-implant keratinized mucosa, in RCTs, CCTs, cohort studies or case series?". Besides KM augmentation, other relevant outcomes such as clinical and radiographic peri-implant outcomes, incidence of biological complications, surgical time, or patient-reported outcome measures (PROMs) were collected. Meta-analyses were performed whenever possible. RESULTS: Ten publications and an unpublished study were included. KM augmentation was significantly greater for autogenous grafts (n = 6; weighted mean difference (WMD) = -0.9 mm; 95% confidence interval (CI) [-1.4; -0.3]; p = .001). However, no significant differences between autogenous grafts and soft tissue substitutes were observed when exclusively xenografts were considered (n = 5; WMD=-0.8 mm; 95% CI [-1.6; 0.0]; p = .062). Surgical time and postsurgical pain seemed to be reduced by the use of soft tissue substitutes. CONCLUSIONS: Free gingival grafts (FGG) are more effective in the augmentation of KM mucosa around dental implants than soft tissue substitutes. However, substitutes of xenogeneic origin may be an alternative to autogenous tissues.

Dimensional changes of keratinized mucosa after accordion versus conventional free gingival graft around dental implants: A randomized two-arm parallel clinical trial.

OBJECTIVES: Free gingival graft (FGG) is the most effective way to increase the apico-coronal width of the keratinized mucosa. In case of limited donor tissue, the accordion technique can be used. This study compared FGG for dimensional and clinical changes using accordion and conventional methods. MATERIALS AND METHODS: Ninety-four implants with keratinized tissue deficiency (<2 mm) were randomly assigned to treatment with accordion (49 implants) and conventional (45 implants) FGG. Endpoints including apico-coronal keratinized tissue width, vertical shrinkage, vestibular depth, probing depth, bleeding on probing, and plaque index were measured. The graft harvesting and recipient bed preparation method were similar in the two groups, and the only difference was the graft length. FGG was harvested with a length 40% shorter than the mesiodistal length of the recipient area in the accordion method and as much as the recipient area in the conventional method. RESULTS: vertical graft shrinkage 1, 3, and 6 months following conventional graft placement was 12.04 ± 14.99, 17.12 ± 20.40, and 23.29 ± 24.63 percent, respectively. In the accordion graft group, the shrinkage was significantly greater with 30.10 ± 16.12, 36.99 ± 15.51, and 43.75 ± 18.78 percent at 1, 3, and 6 months, respectively (p-value < .001). Other factors did not show a clinically significant difference between the two groups. CONCLUSIONS: Comparison of vertical shrinkage changes shows that the shrinkage rate in the accordion group is significantly higher than the conventional group. REGISTRATION NUMBER: IRCT20190721044296N1 (Evaluation of dimensional changes of peri-implant attached mucosa following the treatment of free gingival graft by conventional and accordion methods; randomized clinical trial two-arm parallel).

Efficacy of keratinized mucosal augmentation with a collagen matrix concomitant to the surgical treatment of peri-implantitis: A dual-center randomized clinical trial.

AIM: The aim of this study was to evaluate the efficacy of a xenogeneic collagen matrix to augment the width of keratinized mucosa (KM), concomitantly to the surgical treatment of peri-implantitis, when compared to the use of an autologous soft tissue graft. MATERIAL AND METHODS: In this 12-month parallel-arm randomized controlled clinical trial, patients with peri-implantitis were randomly assigned, one month after non-surgical therapy, to surgical resective treatment of peri-implantitis consisting on an apically positioned flap (APF) in combination with a KM augmentation procedure, either with an autologous free gingival graft (FGG) or a collagen matrix (CM). Primary outcomes were the increase in the width of KM and probing pocket depth (PPD) reduction at 12 months. As secondary outcomes, peri-implant radiographic and patient-reported outcomes were assessed. RESULTS: The intention-to-treat population consisted of 49 subjects, assigned to either the APF + FGG (n = 23) or APF + CM (n = 26) group. PPDs were reduced by 1.6 mm (SD 1.0) and 1.7 mm (SD 1.2), respectively, being these differences non statistically significant (p = .782). However, the increase in KM was significantly higher in the APF + FGG compared with APF + CM (2.5 mm [SD 1.6] vs. 1.6 mm [SD 1.2], respectively (p = .033). CONCLUSION: The tested surgical modalities resulted in similar improvements of the clinical parameters. Both free gingival graft and collagen matrix significantly increased the peri-implant keratinized mucosa, but this KM gain was significantly higher with the free gingival graft. Use of CM, however, was better appreciated by the patients, in terms of pain perception and analgesic consumption, although the surgical time was similar.