Effect of different cone beam computed tomography settings on artifact production in titanium and zirconia dental implants: An in vitro study.

BACKGROUND: The use of dental implants in the treatment of edentulous patients is increasing. Zirconia implants are an alternative to titanium implants, offering advantages in terms of aesthetics and biological compatibility. However, the number of artifacts observed on radiographic images with zirconia implants compared to titanium implants is yet to be determined. OBJECTIVES: The purpose of this study was to evaluate the impact of different cone-beam computed tomography (CBCT) parameters on the production of artifacts in zirconia and titanium implants. MATERIAL AND METHODS: A dry human mandible was coated with wax to simulate human soft tissues and examined. Subsequently, titanium and zirconia implants were placed at the same points in the posterior region of the mandible. The production of artifacts on CBCT scans was evaluated using 2 parameters. The first parameter, the standard deviation within the region of interest (SDROI), is based on a comparison of the gray levels at implant and control areas. The second parameter was the contrast-to-noise ratio (CNR), which was evaluated for different protocols created by various combinations of the field of view (FOV) area, milliampere [mA] intensity and metal artifact reduction (MAR) programs. RESULTS: The study found that zirconia implants produced more artifacts than titanium implants. However, the production of artifacts in zirconia implants could be significantly reduced by increasing the mA values, performing CBCT scans with smaller FOV areas, and enabling MAR programs. CONCLUSIONS: The production of artifacts is a disadvantage of zirconia implants, but this drawback can be mitigated by selecting appropriate protocols for the CBCT device.

Effect of systemic atorvastatin on bone regeneration in critical-sized defects in hyperlipidemia: an experimental study.

PURPOSE: Hypocholesterolemic medications similar to atorvastatin are efficient in lowering blood lipid levels; however, compared to other medications in the statin family, their impact on bone metabolism is claimed to be insufficient. The impact of atorvastatin on bone regeneration in dental implantology in individuals with hyperlipidemia who received atorvastatin in the clinic is doubtful. METHODS: In the study, 16 male New Zealand rabbits of 6 months were used. All rabbits were fed a high-cholesterol diet for 8 weeks, and hyperlipidemia was created. It was confirmed that the total cholesterol level in rabbits was above 105 mg/dl. A critical-sized defect was created in the mandible. The defect was closed with xenograft and membrane. Oral 10 mg/kg atorvastatin was started in the experimental group, and no drug was administered in the control group. At 16th week, animals were sacrificed. For histomorphological examination, the new bone area, osteoclast, and osteoblast activities were evaluated. RESULTS: While new bone area (45,924 µm2, p < 0.001) and AP intensities (105.645 ± 16.727, p = 0.006) were higher in the atorvastatin group than in the control group, TRAP intensities in the control group (82.192 ± 5.346, p = 0.021) were higher than that in the atorvastatin group. CONCLUSIONS: It has been found that high blood lipid levels will adversely affect bone graft healing and the use of systemic atorvastatin contributes to bone healing. Clinicians should pay attention to the selection of surgical materials, considering the importance of questioning drug use in their patients and the risks in cases of non-use.

The effect of different treatment protocols with diode laser on regeneration in axonetmesis injuries of the inferior alveolar nerve: an animal study.

The inferior alveolar nerve can be damaged during dental procedures, leading to symptoms, such as tingling, numbness, and reduced quality of life. Recovery depends on factors such as medications, surgery, and photobiomodulation therapy. Photobiomodulation therapy has shown the potential to improve nerve function and reduce regeneration time; however, there is no standard treatment protocol yet. This study aimed to examine the effect of diode lasers on nerve regeneration in patients with axonetmesis injuries. In this experiment on animals, Wistar rats' damaged sensory systems were treated with lasers to restore them. Animals were randomly divided into six groups: a sham group, a control group, and four laser treatment groups(1st group: performed every day, 10 sessions; 2nd group: performed every 2 days, 10 sessions; 3rd group: performed every day, 20 sessions; and 4th group: performed every 2 days, 20 sessions). Sensory function was determined using the Semmes-Weinstein monofilament test, which was repeated after the surgical procedure. The results showed that the 20-session group had the best improvement, most closely resembling the group without sensory test damage. The histomorphometric results showed that the number of axons was significantly lower in the group that received 10 daily sessions and in the control group than in the undamaged nerve. Axon diameter was lower in all groups than in the sham group. In conclusion, the remarkable aspect of this study is that consecutive-day 20-session laser treatment showed better improvement than the over-the-day 20-session treatment protocol.

Anti-inflammatory and pro-regenerative effects of a monoterpene glycoside on experimental periodontitis in a rat model of diabetes.

OBJECTIVE: Paeoniflorin (Pae) is a monoterpene glycoside with immune-regulatory effects. Several studies have already demonstrated the impact of Pae on periodontitis, but its effect on diabetic periodontitis is unclear. In this study, our aim was to test the hypothesis that Pae had a strong anti-inflammatory effect that prevented bone loss in diabetic periodontitis. METHODS: Thirty male Wistar albino rats were randomly divided into control (healthy, n = 10), periodontitis (PD) + diabetes (DM; n = 10), and PD + DM + Pae (n = 10) groups. Ligature-induced periodontitis was created by placing 4-0 silk ligatures around the lower first molars on both sides of the mandibulae. Experimental DM was created via an injection of 50 mg/kg and streptozotocin (STZ). Hyperglycemia was confirmed by the blood glucose levels of rats (>300 mg/dL). The bone mineral density (BMD), trabecular number, trabecular thickness, and bone loss were measured by micro-CT. The expression levels of IL-1ß, IL-6, and TNF-α were measured in tissue homogenates by ELISA. RESULTS: The PD + DM + Pae group had significantly less alveolar crest resorption when compared to the PD + DM group. There was also a significant difference between the PD + DM + Pae group compared to PD + DM group in trabecular thickness, BMD, and the number of trabeculae. Pae application led to a statistically significant decrease in IL-1ß, IL-6, and TNF-α levels in diabetic periodontitis. CONCLUSION: Systemic application of Pae suppressed inflammation caused by PD and DM, leading to reduced bone loss and enhanced bone quality.

Effect of Photobiomodulation Therapy on Peri-Implant Bone Healing in Extra-Short Implants in a Rabbit Model: A Pilot Study.

Objective: To evaluate the effects of photobiomodulation therapy (PBMT) at distinct energy levels on peri-implant bone healing in extra-short implants in a experimental rabbit model. Background: The effect of PBMT on peri-implant bone healing in short implants remains unclear. This explored the effect of PBMT on extra-short implants in terms of bone-implant contact (BIC) length and rate, and implant stability quotient (ISQ). Methods: Fifteen white New Zealand rabbits were randomly divided into five groups. In all groups, extra-short implants (3.5 × 4 mm; Nucleoss T6, Izmir/Turkey) were placed in both tibias of the rabbits. PBMT was performed in four groups (group 1, 5 J/cm2; group 2, 10 J/cm2; group 3, 20 J/cm2; and group 4, 25 J/cm2); no PBMT was performed in the control group. On the 30th day, the rabbits were sacrificed and peri-implant tissue samples were obtained to determine the BIC length and BIC rate. Implant stability levels were measured by resonance frequency analysis using the Osstell penguin device and were determined as ISQ values on the 1st and 30th days of the study. Results: PBMT significantly increased the BIC length and BIC rate in groups 3 and 4 (p < 0.001). For the ISQ values, there were significant differences between the 1st and 30th day (p < 0.001). On the 30th day, the ISQ values were significantly higher in groups 3 and 4 compared with the remaining groups (p < 0.001). Conclusions: In this study, PBMT improved peri-implant bone healing through increase in BIC length, BIC rate, and ISQ parameter values in extra-short implants.