Does Periosteal Graft Combined With Platelet-Rich Plasma Enhance the Healing of Bone Defect?

INTRODUCTION: This study investigated the effect of periosteal graft + platelet-rich plasma (PRP) combination on facial bone defect healing. METHODS: Five-millimeter critical sized defects in zygomatic arches of 12 adult New Zealand rabbits were created. Rabbits were randomly divided into 3 groups: First group (control group): bone defects of left zygomatic arches of 6 rabbits were wrapped with a silicone tube. Second group (periosteal graft group): bone defects of left zygomatic arches of 6 rabbits were wrapped with periosteal graft. Third group (experimental group): bone defects of right zygomatic arches of 12 rabbits were wrapped with periosteal graft-PRP combination. New bone formation was evaluated at 8th and 16th weeks. One rabbit was sacrificed at 8th week. Remaining 11 rabbits were imaged with 3-dimensional computed tomography (CT) at 16th week; then, zygomatic arches were removed for micro-CT and histologic examinations. RESULTS: Three-dimensional CT analysis at 16th week revealed no significant difference between groups regarding new bone formation (P = 0.232). Micro-CT analysis of new regenerated bone at 16th week displayed significant differences between groups 1 and 3 regarding mean bone volume (BV, mm) (P = 0.028) and mean bone mineral density (BMD, mm) (P = 0.001). There was no difference between groups 2 and 3 or between groups 1 and 2, regarding BV or BMD. Histological Bone Regeneration Scorings at 16th week displayed significant difference between groups (P = 0.015). Negative correlation between 3-dimensional CT and histologic results (r = 0.120); positive correlations between BV/BMD values in micro-CT and histologic results (r = 0.524 and r = 0.456) were found. CONCLUSIONS: By enhancing bone formation capacity of periosteal grafts, periosteal graft-PRP combination provided bone formation having more volume and density comparing with silicone tube application.

The Importance of the Trigeminal Cardiac Reflex in Rhinoplasty Surgery.

BACKGROUND: Trigeminocardiac reflex (TCR) consists of bradycardia or asystole along with hypotension and apnea coinciding with stimulation of the trigeminal nerve. During rhinoplasty procedures, we noticed that local anesthetic solution (LAS) application to the columellar area results in bradycardia. We planned to conduct a randomized prospective study on 47 patients undergoing rhinoplasty to demonstrate the characteristics of TCR arising from the columella. METHOD: Local anesthetic solution containing 2% prilocaine with 1:80,000 adrenaline was applied under standard general anesthesia protocol. In group 1 (study group, n = 24), 2 mL of LAS was applied to the columella. In group 2 (control group, n = 23), 2 mL of LAS was applied to the nasal dorsum. In group 3 (control group, n = 20), after LAS was applied to nasal dorsum in group 2, we waited for 10 minutes. Then, 2 mL of LAS was applied to the columella. Here, recordings were taken for the columella.Heart rate (HR) and blood pressure (BP) were recorded just before needle insertion (baseline level), at the time of needle insertion (NIT) to the columella or dorsum, and after the 1st, 5th, 10th, 30th, and 60th seconds. RESULTS: Transient bradycardia (≥20% drop in HR) was observed in 33% of the patients in group 1.Decrease in HR compared to the baseline level in group 1 was significantly greater than that of groups 2 and 3 at all times (P ≤ 0.05).Systolic BP in NIT and in 60th second in group 1, only in NIT in group 2 was significantly lower than that of baseline levels (P ≤ 0.05). CONCLUSIONS: We concluded that stimulation of a sensory branch of the trigeminal nerve in the columellar area leads to TCR under general anesthesia by eliciting clinical hypotension with a drop in systolic BP and in HR of more than 20% compared to the baseline level.Knowing the existence of a certain TCR area will be helpful to the surgeon and anesthesiologist to exercise extra vigilance and to make continuous and meticulous monitoring of the electrocardiogram, HR, and BP during which the TCR may be precipitated such as local anesthetic infiltration to the columellar area in rhinoseptoplasty operations.