A Novel Approach to Monitoring Graft Neovascularization in the Human Gingiva

Summary

This study introduces a protocol for measuring microcirculation in human oral mucosa by laser speckle contrast imaging. The monitoring of wound healing after vestibuloplasty combined with a xenogenic collagen graft is presented on a clinical case.

Abstract

Laser speckle contrast imaging (LSCI) is a novel method for measuring superficial blood perfusion over large areas. Since it is non-invasive and avoids direct contact with the measured area, it is suitable for monitoring blood flow changes during wound healing in human patients. Vestibuloplasty is periodontal surgery to the oral vestibule, aiming to restore vestibular depth with simultaneous enlargement of the keratinized gingiva. In this special clinical case, a split thickness flap was elevated at the first upper premolar and a xenogenic collagen matrix was adapted to the resulting recipient bed. LSCI was used to monitor the re- and neovascularization of the graft and the surrounding mucosa for one year. A protocol is introduced for the correct adjustment of microcirculation measurement in the oral mucosa, highlighting difficulties and possible failures.

The clinical case study presented demonstrated that — following the appropriate protocol — LSCI is a suitable and reliable method for following up microcirculation in a healing wound in the human oral mucosa and gives useful information on graft integration.

Introduction

Monitoring long-term changes of human gingival microcirculation in a clinical situation is a hot topic in oral and periodontal surgery. However, reliable assessment of perfusion can be difficult. There are only a few methods that do not invasively measure changes in the blood circulation of the human mucosa. Two of these employ a laser beam^1,2,3,4, but in a different way. Laser doppler flowmetry (LDF) makes use of the Doppler shift in a laser beam^5,6, while the laser speckle contrast....

Protocol

The reported method was employed in a clinical trial which was granted ethical approval from the Hungarian Committee of the Health Registration and Training Center (approval number: 034310/2014/OTIG).

1. LSCI Setup

1. Switch on the computer and any peripherals.
2. Switch on the LSCI instrument to be used with the switch on the rear panel.
3. Allow the instrument to warm up for at least 5 min. The instrument is ready for measurement when both LEDs on the rear panel have stopped flashing.
4. Start the software by double-clicking on the software icon on the desktop or via the Start menu.
5. Wait until both ....

Results

Vestibuloplasty is periodontal surgery to the oral vestibule, aiming to increase vestibular depth, the zone of keratinized gingiva and soft tissue thickness for enhanced aesthetics and function. The apically repositioned split thickness flap combined with a collagen matrix is a frequently used vestibuloplasty procedure. Xenogenic collagen matrix is a viable alternative to autogenous gingival graft for increasing the amount of keratinized gingiva^11,

Discussion

The aim of this study was to introduce a novel technique for monitoring the neovascularization of a graft in the human gingiva. According to our previous results, LSCI assesses the blood perfusion of the gingiva with good repeatability and reproducibility⁹, when strict implementation of each step of the planned protocol as a critical requirement is met. LSCI is regarded as a semi-quantitative technique that requires calibration periodically to ensure accuracy and stability. During verification, th.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
PeriCam PSI-HR	Perimed AB, Stockholm, Sweden		The PeriCam PSI System is an imaging system based on LASCA technology (LAser Speckle Contrast Analysis). The system measures superficial blood perfusion over large areas at fast capture rates. This makes it ideal for investigations of both the spatial and temporal dynamics of microcirculation in almost any tissue.
PIMSoft	Perimed AB, Stockholm, Sweden		PIMSoft is a data acquisition and analysis software, intended for use together with the PeriCam PSI System and the PeriScan PIM 3 System, for measurement and imaging of superficial blood perfusion.
Geistlich Mucograft	Geistlich, Switzerland		It's a unique 3D collagne matrix designed specifically for soft tissue regeneration. It's indicated for the gain of keratinized tissue and recession coverage.
Omron M4	Omron Healthcare Inc., Kyoto, Japan		Blood pressure monitor, which gives accurate readings.
Nikon D5200	Nikon Corportation, Tokyo, Japan		Taking intra oral photos
MS Excel	Microsoft Corporation, Redmond, Washington, USA		The software used for data management
IBM SPSS Statistics 25	IBM Corp., Armonk, NY, USA		The software used for statistical analysis