Evaluation of Preventive Role of Systemically Applied Erythropoietin after Tooth Extraction in a Bisphosphonate-Induced MRONJ Model

Background and Objectives: In this experimental study, the prophylactic effect of systemically administered erythropoietin (EPO) in medication-related osteonecrosis of the jaw (MRONJ) was evaluated. Materials and Methods: The osteonecrosis model was established using 36 Sprague Dawley rats. EPO was systemically applied before and/or after tooth extraction. Groups were formed based on the application time. All samples were evaluated histologically, histomorphometrically, and immunohistochemically. A statistically significant difference in new bone formation was observed between the groups (p < 0.001). Results: When new bone-formation rates were compared, no significant differences were observed between the control group and the EPO, ZA+PostEPO, and ZA+Pre-PostEPO groups (p = 1, 0.402, and 1, respectively); however, this rate was significantly lower in the ZA+PreEPO group (p = 0.021). No significant differences in new bone formation were observed between the ZA+PostEPO and ZA+PreEPO groups (p = 1); however, this rate was significantly higher in the ZA+Pre-PostEPO group (p = 0.009). The ZA+Pre-PostEPO group demonstrated significantly higher intensity level in VEGF protein expression than the other groups (p < 0.001). Conclusions: Administering EPO two weeks pre-extraction and continuing EPO treatment for three weeks post-extraction in ZA-treated rats optimized the inflammatory reaction, increased angiogenesis by inducing VEGF, and positively affected bone healing. Further studies are needed to determine the exact durations and doses.

Use of Leukocyte-rich and Platelet-rich Fibrin (L-PRF) Adjunct to Surgical Debridement in the Treatment of Stage 2 and 3 Medication-Related Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ) is characterized by exposed necrotic bone persisting for more than 8 weeks in the maxillofacial region in patients using antiresorptive or antiangiogenetic drugs for several treatment options like bone metastasis or osteoporosis. There are several treatment options studied in scientific literature, and one of them with promising results is using platelet concentrates adjunct to surgical therapy. The aim of this study is to examine the therapeutic effect of leukocyte and platelet-rich fibrin (L-PRF) on patients with MRONJ. This 2-centered study investigated patients referred to oral and maxillofacial surgery departments of 2 university clinics between the years 2014 and 2020 with the diagnosis of MRONJ. Demographic data, the indication of the drug usage, drug type, duration, administration route, and systemic comorbidities of the patients were recorded. L-PRF was applied to 20 osteonecrotic lesions of 19 patients following surgical debridement. The male/female ratio was 5/14. Except 1 of the patients, all of the indications of medication were neoplasia-related. The mean follow-up period of patients was 27.9±9.2 months. Most common antirezorptive drug was zoledronate (84.2%). Complete resolution was observed in 16 necrosis sites (80%). It could be concluded that the use of L-PRF may represent an important adjunct in the surgical management of MRONJ.

Could Local Application of Hypoxia Inducible Factor 1-α Enhancer Deferoxamine Be Promising for Preventing of Medication-Related Osteonecrosis of the Jaw?

This experimental study investigates the prophylactic effect of deferoxamine (DFO) on medication-related osteonecrosis of the jaw (MRONJ). Thirty-six female Sprague Dawley rats received zoledronic acid (ZA) for eight weeks to create an osteonecrosis model. DFO was locally applied into the extraction sockets with gelatin sponge (GS) carriers to prevent MRONJ. The specimens were histopathologically and histomorphometrically evaluated. Hypoxia-inducible factor 1-alpha (HIF-1α) protein levels in the extraction sockets were quantified. New bone formation rate differed significantly between groups (p = 0.005). Newly formed bone ratios in the extraction sockets did not differ significantly between the control group and the GS (p = 1), GS/DFO (p = 0.749), ZA (p = 0.105), ZA-GS (p = 0.474), and ZA-GS/DFO (p = 1) groups. While newly formed bone rates were higher in the ZA-GS and ZA-GS/DFO groups than in the ZA group, the differences were not significant. HIF-1α levels differed significantly between groups (p < 0.001) and were significantly higher in the DFO and ZA-GS/DFO groups than in the control group (p = 0.001 and p = 0.004, respectively). While HIF-1α levels were higher in the ZA-GS/DFO group than in the ZA group, the difference was not significant. While HIF-1α protein levels and new bone formation rate were elevated in the DFO-treated group, the effect was not significant. Further large-scale studies are needed to understand DFO’s preventative effects on MRONJ and the role of HIF-1α in MRONJ pathogenesis.

Antibiotic prescribing habits of the clinicians dealing with dental implant surgery in Turkey: a questionnaire study

PURPOSE

Although various prophylactic and/or postoperative systemic antibiotic regimens have been suggested to minimize failure after dental implant placement and postoperative infection, the role of antibiotics in implant dentistry is still controversial. The purposes of this questionnaire study were to determine the current antibiotic prescribing habits of clinicians in conjunction with dental implant placement and to understand whether any consensus has been reached among implant surgery performing clinicians.

METHODS

An electronic questionnaire was sent by electronic mail to all members of the Turkish Dental Society. The questions were related to whether antibiotics were routinely prescribed either pre- or/and postoperatively during routine dental implant placement. The respondents were also asked to specify their workplace and education. The results were analyzed using SPSS software. Descriptive and chi-square analyses were used to compare categorical data; Kruskal-Wallis test was used to compare the quantitative data by category.

RESULTS

A total of 429 members responded to the questionnaire. The clinicians having more experience had a greater tendency to prescribe preoperative antibiotics (p < 0.001), but there was no statistically significant difference between the postoperative antibiotic prescription choice of the clinician according to the clinicians' experience (p > 0.05). A total of 175 of the clinicians preferred to prescribe preoperative antibiotics when there was systemic comorbidity; 99 of the clinicians preferred to prescribe antibiotics before every implant surgery. The aminopenicillins were the most commonly prescribed antibiotics by the clinicians. A total of 38.58% of the respondents (n = 130) who were prescribing preoperative antibiotics, 2000 mg aminopenicillin was given 1 h before the surgical procedure. Dentists and solo private practitioners were prescribing more preoperative antibiotics (p < 0,05).

CONCLUSIONS

There was no consensus among clinicians regarding the use of antibiotics in association with routine dental implant placement. Aminopenicillins were the most commonly prescribed antibiotics for both pre- and postoperatively. Furthermore, most of the antibiotic regimens being used are not in accordance with the current published data.

Is there any predictive bone parameter for implant stability in 2-dimensional and 3-dimensional radiologic images?

OBJECTIVES

This ex vivo study aimed to compare radiomorphometric parameters between 2-dimensional (2-D) and 3-dimensional (3-D) radiographs and evaluate the influence of preoperative radiologic bone parameters on the clinical outcomes of implant stability.

STUDY DESIGN

Implant recipient sites in fresh bovine blocks were evaluated on panoramic radiographs for gray value (GV), fractal dimension (FD), number of connected trabeculae (Co), and density of connected trabeculae (CoD). Cone beam computed tomography (CBCT) scans were evaluated for trabecular thickness (TbTh), cortical thickness (CTh), degree of anisotropy (DA), FD, and Co. Insertion torque (IT) and implant stability quotient (ISQ) were measured.

RESULTS

GV was significantly correlated with all parameters in 2-D and 3-D images except FD in 2-D and Co in 3-D, and with all surgical parameters (P ≤ .029). Co and CoD values on panoramic radiographs had significant correlation with TbTh, CTh, and DA values on CBCT images (P < .001). All 2-D parameters and TbTh and CTh in the CBCT data were significantly correlated with IT only (P ≤ .047). Only GV was correlated with ISQ measurements (P ≤ .029).

CONCLUSIONS

GV, Co, and CoD values on panoramic radiographs reflect the architecture of trabecular bone and the thickness of cortical bone, and might help predict implant stability in clinical situations.