Connective tissue graft versus xenogeneic collagen matrix for soft tissue augmentation at implant sites: a randomized-controlled clinical trial

OBJECTIVES

The purpose of this randomized clinical trial (RCT) is to compare xenogeneic collagen matrix (XCM) versus subepithelial connective tissue graft (SCTG) to increase soft tissue thickness at implant site.

MATERIALS AND METHODS

The study was a randomized, parallel-group controlled investigation. Thirty patients underwent buccal soft tissue thickness augmentation at the stage of implant placement by two different methods: SCTG (control group) and XCM (test group). Primary outcome was the amount of buccal soft tissue thickness gain, 3 months after the intervention. Secondary outcomes were the operation time, the amount of keratinized mucosa (KM), pain syndrome (PS), and patients' quality of life (QL). Histologic evaluation was also performed.

RESULTS

The amount of soft tissue thickness gain was 1.55±0.11 mm in SCTG group, and 1.18±0.11mm in XCM group. The difference between the SCTG and XCM was -0.366 (-0.66 to -0.07; p=0.016). Operation time with XCM was 8.4 (3.737 to 13.06) min shorter than that with the SCTG (p=0.001). KT, PS, and QL for both groups were not statistically significantly different at any time point (p>0.05). At histological examination, the general picture in both groups was similar. No significant differences between the studied groups in most indices, except for the average and maximum formation thickness, cellularity of the basal, mitotic activity and also maximum length of rete ridges.

CONCLUSION

Within limitations, this study demonstrates that the use of SCTG provides a statistically significant superior soft tissue thickness gain than XCM for soft tissue augmentation procedures around implants.

CLINICAL RELEVANCE

XCM can be used as the method of choice for increasing the thickness of soft tissues.

Spray with Nitric Oxide Donor Accelerates Wound Healing: Potential Off-the-Shelf Solution for Therapy?

Background

Ditrosyl iron complexes (DNIC) are endogenous donors of nitric oxide. The possibility of their application to stimulate regeneration has been studied for more than 15 years. However, the most effective dose and form of delivery have not yet been determined.

Purpose

The aim of this research was to develop a spray form of DNIC that accelerates wound healing.

Methods

We prepared a series of DNIC sprays with spray dosages of 10, 50 and 100 μg. We modelled full-thickness skin wounds in 24 Wistar rats and treated them with distilled water (n = 6), 10 (n = 6), 50 (n = 6) and 100 μg (n = 6) for three post-operative days. On the fourth day, the excised wound tissues were studied by morphological, immunohistochemical and morphometric methods.

Results

We demonstrated that 50 μg of DNIC spray had the most beneficial effect on wound healing: the thickness of the granulation tissue layer was 140% higher, vimentin positive fibroblasts predominated and the intensity of inflammation was significantly lower than in the control. There was a dose-dependent decrease in the functional activity of mast cells in the experimental groups compared to the control.

Conclusion

DNIC spray is a potential effective dosage form for the treatment of large-area skin lesions.

Implantable Drug Delivery Systems and Foreign Body Reaction: Traversing the Current Clinical Landscape

Precise delivery of therapeutics to the target structures is essential for treatment efficiency and safety. Drug administration via conventional routes requires overcoming multiple transport barriers to achieve and maintain the local drug concentration and commonly results in unwanted off-target effects. Patients’ compliance with the treatment schedule remains another challenge. Implantable drug delivery systems (IDDSs) provide a way to solve these problems. IDDSs are bioengineering devices surgically placed inside the patient’s tissues to avoid first-pass metabolism and reduce the systemic toxicity of the drug by eluting the therapeutic payload in the vicinity of the target tissues. IDDSs present an impressive example of successful translation of the research and engineering findings to the patient’s bedside. It is envisaged that the IDDS technologies will grow exponentially in the coming years. However, to pave the way for this progress, it is essential to learn lessons from the past and present of IDDSs clinical applications. The efficiency and safety of the drug-eluting implants depend on the interactions between the device and the hosting tissues. In this review, we address this need and analyze the clinical landscape of the FDA-approved IDDSs applications in the context of the foreign body reaction, a key aspect of implant–tissue integration.