Healing of Experimental Periodontal Defects Following Treatment with Fibroblast Growth Factor-2 and Deproteinized Bovine Bone Mineral

Double-sided entire papilla preservation technique in the combination periodontal regenerative therapy: A case report

BACKGROUND

With the entire papilla preservation (EPP) technique, it is possible to perform regenerative therapy without incisions in the interdental papilla and to reduce the risk of papillary rupture. However, one limitation of the EPP is the sole access from the buccal side. Here, we present a case of periodontitis treated by the combination regenerative therapy employing the Double-sided (buccal-palatal) EPP (DEPP) technique, which adds a palatal vertical incision to the EPP.

METHODS

A patient with 1-2 wall intrabony defects received the regenerative therapy using recombinant human fibroblast growth factor (rhFGF)-2 and carbonate apatite (CO3Ap). Using the DEPP technique, vertical incisions at buccal and palatal aspects were placed to gain adequate access to the 1-2 wall intrabony defects between #11 and #12 without incision in the interdental papilla. After debridement, rhFGF-2 and CO3Ap were applied to the defect. Periodontal clinical parameters and radiographic images were evaluated at the first visit, following initial periodontal therapy (baseline), 6, 9, and 12 months postoperatively.

RESULTS

Wound healing was uneventful. Scarring of the incision lines was minimal. At 12 months postoperatively, probing depth reduction was 4 mm, clinical attachment gain was 4 mm, and gingival recession was not observed. An improvement in radiopacity in the previous bone defect was observed.

CONCLUSION

The DEPP is an innovative technique that allows approaching from both the buccal and palatal sides while ensuring flap extensibility without compromising the interdental papilla. This report suggests that the combination of regenerative therapy with the DEPP may be promising in the treatment of intrabony defects.

KEY POINTS

Why is this case new information? The DEPP allows a direct visual approach to a 1-2 wall intrabony defect extending from the buccal to palatal sides, and increases flap extensibility, without compromising the papilla. What are the keys to the successful management of this case? Assessment of three-dimensional bone defect morphology is required. Computed tomography images are very useful. The flap elevation just under the interdental papilla should be carefully performed with a small excavator to avoid damage to the interdental papilla. What are the primary limitations to success in this case? Despite the addition of a palatal incision, it was not possible to obtain complete flexibility of the palatal gingiva. Caution must be taken in a case in which the distance between the interdental papilla is narrow. Even if the interdental papilla is ruptured during the operation, recovery is possible by continuing the operation and suturing the rupture at the end.

Mitochondrial Redox Balance of Fibroblasts Exposed to Ti-6Al-4V Microplates Subjected to Different Types of Anodizing

Despite the high biocompatibility of titanium and its alloys, the need to remove titanium implants is increasingly being debated due to the potential for adverse effects associated with long-term retention. Therefore, new solutions are being sought to enhance the biocompatibility of titanium implants. One of them is to increase the thickness of the passive layer of the implant made of titanium dioxide. We were the first to evaluate the effect of hard-anodized (type II) Ti-6Al-4V alloy discs on the cytotoxicity, mitochondrial function, and redox balance of fibroblasts mitochondria compared to standard-anodized (type III) and non-anodized discs. The study used fibroblasts obtained from human gingival tissue. The test discs were applied to the bottom of 12-well plates. Cells were cultured for 24 h and 7, 14, and 21 days and mitochondria were isolated. We demonstrated the occurrence of oxidative stress in the mitochondria of fibroblasts of all tested groups, regardless of the presence and type of anodization. Type II anodization prevented changes in complex II activity (vs. control). The lowest degree of citrate synthase inhibition occurred in mitochondria exposed to titanium discs with type II anodization. In the last phase of culture, the presence of type II anodization reduced the degree of cytochrome c oxidase inhibition compared to the other tests groups and the control group, and prevented apoptosis. Throughout the experiment, the release of titanium, aluminium, and vanadium ions from titanium discs with a hard-anodized passive layer was higher than from the other titanium discs, but decreased with time. The obtained results proved the existence of dysfunction and redox imbalance in the mitochondria of fibroblasts exposed to hard-anodized titanium discs, suggesting the need to search for new materials perhaps biodegradable in tissues of the human body.

Periodontal Regenerative Therapy Using rhFGF-2 and Deproteinized Bovine Bone Mineral versus rhFGF-2 Alone: 4-Year Extended Follow-Up of a Randomized Controlled Trial

The aim of this study was to evaluate longitudinal outcomes of recombinant human fibroblast growth factor (rhFGF)-2 plus deproteinized bovine bone mineral (DBBM) therapy in comparison with rhFGF-2 alone for treating periodontal intrabony defects. This study describes 4-year follow-up outcomes of the original randomized controlled trial. Intrabony defects in periodontitis patients were treated with rhFGF-2 (control) or rhFGF-2 plus DBBM (test). Clinical, radiographic, and patient-reported outcome (PRO) measures were used to evaluate the outcomes. Thirty-two sites were able to be followed up. At 4 years postoperatively, clinical attachment level (CAL) gains in the test and control groups were 3.5 ± 1.4 mm and 2.7 ± 1.4 mm, respectively, showing significant improvement from preoperative values but no difference between groups. Both groups showed an increase in radiographic bone fill (RBF) over time. At 4 years, the mean value for RBF in the test group (62%) was significantly greater than that in the control group (42%). In 1-2-wall defects, the test treatment yielded significantly greater RBF than the control treatment. No significant difference in PRO scores was noted between the groups. Although no significant difference in CAL gain was found between the groups at the 4-year follow-up, the combination treatment significantly enhanced RBF. Favorable clinical, radiographic outcomes, and PRO in both groups can be maintained for at least 4 years.

Surgical Periodontal Therapy Using Recombinant Human Fibroblast Growth Factor-2 in Combination with Carbonate Apatite Granules for Stage III Grade B Periodontitis: A Case Report with 1-year Follow-up

This report describes a case of generalized chronic periodontitis requiring periodontal treatment including regenerative therapy. The patient was a 60-year-old woman who visited the Tokyo Dental College Suidobashi Hospital with the chief complaint of tooth mobility and pain in tooth #26. Periodontal examination at the first visit revealed that 32.0% of sites had a probing depth of ≥4 mm and 43.8% bleeding on probing. Radiographic examination revealed vertical bone resorption in #17. Horizontal resorption was noted in other areas. Initial periodontal therapy consisting of plaque control, scaling and root planing, and caries treatment was performed based on a clinical diagnosis of Stage III Grade B periodontitis. Tooth #26 was extracted due to bone resorption extending as far as the root apex. After reevaluation, periodontal regenerative therapy using recombinant human fibroblast growth factor-2 (rhFGF-2) in combination with carbonate apatite (CO₃Ap) granules was performed for #17. Following reevaluation, a zirconia crown (#16) and zirconia bridge (#24-27) were placed. Following further reevaluation, the patient was placed on supportive periodontal therapy (SPT). The periodontal regenerative therapy using rhFGF-2 with CO₃Ap granules yielded an improvement in the vertical bone resorption observed in #17. This improvement has been adequately maintained over a 1-year period postoperatively. Continued SPT is needed to maintain stable periodontal conditions.

Investigating the Effects of Dehydrated Human Amnion-Chorion Membrane on Periodontal Healing

Each growth factor (GF) has different effects and targets, and plays a critical role in periodontal healing. Dehydrated human amnion-chorion membrane (dHACM) contains various GFs and has been used to enhance wound healing. The purpose of this study was to evaluate the effects of dHACM on periodontal healing, using in vitro and in vivo experimental approaches. Standardized periodontal defects were created in rats. The defects were randomly divided into three groups: Unfilled, filled with hydroxypropyl cellulose (HPC), and dHACM+HPC. At 2 and 4 weeks postoperatively, periodontal healing was analyzed by microcomputed tomography (micro-CT), and histological and immunohistochemical analyses. In vitro, periodontal ligament-derived cells (PDLCs) isolated from rat incisors were incubated with dHACM extract. Cell proliferation and migration were evaluated by WST-1 and wound healing assay. In vivo, micro-CT examination at 2 weeks revealed enhanced formation of new bone in the dHACM+HPC group. At 4 weeks, the proportions of vascular endothelial growth factor (VEGF)-positive cells and α-smooth muscle actin (α-SMA)-positive blood vessels in the dHACM+HPC group were significantly greater than those in the Unfilled group. In vitro, dHACM extracts at 100 µg/mL significantly increased cell proliferation and migration compared with control. These findings suggest that GFs contained in dHACM promote proliferation and migration of PDLCs and angiogenesis, which lead to enhanced periodontal healing.

Comparison of periodontal wound healing/regeneration by recombinant human fibroblast growth factor-2 combined with β-tricalcium phosphate, carbonate apatite, or deproteinized bovine bone mineral in a canine one-wall intra-bony defect model

AIM

To evaluate periodontal wound healing/regeneration of one-wall intra-bony defects treated with recombinant human fibroblast growth factor-2 (rhFGF-2) and beta-tricalcium phosphate (β-TCP), carbonate apatite (CO₃ Ap), or deproteinized bovine bone mineral (DBBM) in dogs.

MATERIALS AND METHODS

The stability of rhFGF-2 adsorbed onto the bone substitutes was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). One-wall intra-bony defects (5 × 5 × 5 mm) created in five adult male beagle dogs were treated with rhFGF-2 alone (rhFGF-2), rhFGF-2 with β-TCP (rhFGF-2/β-TCP), rhFGF-2 with CO₃ Ap (rhFGF-2/CO₃ Ap), or rhFGF-2 with DBBM (rhFGF-2/DBBM). Histological outcomes (e.g., linear length of new cementum adjacent to the newly formed bone with inserting collagen fibres [NA] as the primary outcome) were evaluated at 10 weeks post surgery.

RESULTS

Significantly higher amount of rhFGF-2 was adsorbed onto CO₃ Ap compared with β-TCP. Among the treatment groups, the rhFGF-2/DBBM group showed the highest amount of periodontal tissue regeneration. The rhFGF-2/DBBM group showed significantly greater formation of NA (3.22 ± 0.40 mm) compared with rhFGF-2 (1.17 ± 1.00 mm, p < .01) group. Additionally, new bone area in the rhFGF-2/DBBM group (9.78 ± 2.30 mm² ) was significantly higher than that in the rhFGF-2 (5.08 ± 1.26 mm² , p < .01), rhFGF-2/β-TCP (5.91 ± 1.27 mm² , p < .05), and rhFGF-2/CO₃ Ap (6.51 ± 1.49 mm² , p < .05) groups. Slight ankylosis was found in the rhFGF-2/β-TCP (1/9 sites), rhFGF-2/CO₃ Ap (3/10 sites), and rhFGF-2/DBBM (1/9 sites) groups.

CONCLUSIONS

Within their limitations, the present data indicate that DBBM seems to be a suitable carrier for rhFGF-2 and that rhFGF-2/DBBM treatment promotes favourable periodontal regeneration compared with rhFGF-2, rhFGF-2/β-TCP, and rhFGF-2/CO₃ Ap treatments in one-wall intra-bony defects.