Effects of zoledronic acid and dexamethasone on early phases of socket healing after tooth extraction in rats: A preliminary macroscopic and microscopic quantitative study.

BACKGROUND: The exact pathogenesis of medication-related osteonecrosis of the jaw (MRONJ) is still unknown. The aim of this paper was to investigate the effects of zoledronic acid and dexamethasone on the early phases of socket healing in rats subjected to tooth extractions. MATERIAL AND METHODS: Thirty male Sprague-Dawley rats were divided into 2 groups: pharmacologically treated group (T, n=20) and non-pharmacologically treated group (C, n=10). T group rats received 0.1 mg/Kg of zoledronic acid (ZOL) and 1 mg/Kg of dexamethasone (DEX) three times a week for 10 consecutive weeks. C group rats were infused with vehicle. After 9 weeks from the first infusion, first maxillary molars were extracted in each of the rats. Quantitative macroscopic and microscopic analysis was performed to evaluate socket healing 8 days after extraction. RESULTS: Pharmacologically treated rats showed significant inhibition of bone remodeling. Connective tissue/alveolar bone ratio, osteoclast number and woven bone deposition were significantly reduced in group T compared to group C. Conversely, the proportion of necrotic bone was higher in group T compared to group C (0.8% and 0.3%, respectively. P=0.031). ZOL plus DEX do not cause gross effects on socket healing at a macroscopic level. CONCLUSIONS: Our findings confirmed that exposure to ZOL plus DEX impairs alveolar wound repair. Inhibition of osteoclastic resorption of socket walls after tooth extraction and the inability to dispose of the necrotic bone may be considered the initial steps of MRONJ onset.

A 5-year retrospective longitudinal study on the incidence and the risk factors of osteonecrosis of the jaws in patients treated with zoledronic acid for bone metastases from solid tumors.

BACKGROUND: The aim of this study was to evaluate the incidence and the risk factors of osteonecrosis of the jaw (ONJ) in a group of patients treated with zoledronic acid (ZA) for bone metastases from solid tumors and enrolled in a preventive dental program. MATERIAL AND METHODS: This 5-year retrospective longitudinal study included all consecutive oncological patients who underwent at least one infusion with ZA between 2004 and 2011 for bone metastases due to solid neoplasms. RESULTS: Of the 156 patients enrolled in the study, 17 developed ONJ (10.89%). At the multivariate analysis, severe periodontal disease (P=0.025), tooth extraction (P<0.0001) and starting the preventive dental program after the beginning of ZA therapy (P=0.02) were the only factors which showed a significant association with the occurrence of ONJ. CONCLUSIONS: This study demonstrated the importance of beginning dental prevention before zoledronic acid exposure in reducing ONJ occurrence, especially in the long term. The results of this research show that control of periodontal disease and an increase in the time between tooth extraction and the first ZA administration are recommended in order to reduce the risk of ONJ development.

Postoperative discomfort in oral soft tissue surgery: a comparative perspective evaluation of Nd:YAG Laser, quantic molecular resonance scalpel and cold blade.

AIM: The aim of this paper was to compare pain, health-related quality of life (HRQoL) and need for painkillers during the postoperative course of oral soft tissue surgery performed with neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, quantic molecular resonance (QMR) scalpel and cold blade. METHODS: One-hundred and sixty-three similar surgical interventions were subclassified as follows: group 1 (G1), 77 cases performed with Nd:YAG laser; group 2 (G2), 45 cases performed with QMR scalpel and group 3 (G3), 41 cases performed with cold blade. Pain was evaluated using a Visual Analogue Scale (VAS), a Numeric Rating Scale (NRS) and a Verbal Rating Scale-6 (VRS-6) on the same day of surgery (day 0), and at 1, 3 and 7 days after surgery. The HRQoL was evaluated on day 7 using a 0-45 score range questionnaire. On day 7, painkillers taken were recorded. RESULTS: No statistically significant differences could be highlighted in the VAS and NRS scores at day 1, 3 and 7. A trend toward significance at day 0 was evident, with a VAS and NRS average scores lower in G1 than G2 and G3. With regard to VRS-6, the scores resulted statistically lower in G1 than G2 and G3 at day 1 and 3. The HRQoL in G1 was statistically lower than G3. CONCLUSION: Our study demonstrates that the use of new technologies in oral soft tissue surgery is associated to a reduction of postoperative discomfort. The better HRQoL and the lower postoperative pain observed in laser-treated patients may be associated to the possible bio-modulating effect of the laser.