Polyetheretherketone (PEEK) material is a polycyclic, aromatic, thermoplastic polymer that is semi-crystalline and has a linear structure. PEEK has good mechanical and electrical properties such as resistance to high temperature and resistance to hydrolysis. In addition, because of the property of high biocompatibility, use of PEEK has increased in orthopaedic and trauma cases. The most characteristic property of PEEK material is that it has a low elasticity modulus, close to that of bone. It has been suggested that stress-based problems could be reduced with this material due to the low elasticity modulus. In the light of this information, PEEK material could be considered as an alternative to conventional materials in the field of dentistry.

Aims: The purpose of this study is to compare the stresses occurring in the peri-implant bones, implants, crowns, abutments, and screws after loading through finite element analysis by using the poly-ether-ether-ketone (PEEK) materials, which are alternative to titanium abutment and metal supported restorations and to try to reduce the level of neck resorption. Materials and Methods: In our study, three-dimensional modeling of 2 PEEK and titanium abutments, metal-ceramic, and monolithic PEEK upper central dental restorations were made on four titanium implants (Biohorizons^® Implant Systems Ins., Birmingham, AL, USA) with diameters of 3.8 mm and 10.5 mm and four groups were obtained. Then, a stress analysis of the finite element was performed by applying a 178 N oblique force of 45° to the long axis of the tooth 2 mm below the incisal edge of the model's palatal surface. Results: It has been observed that the PEEK material reduces the stresses caused by the force applied on itself during all tests. In all groups, PEEK abutments and PEEK crowns have reduced stress on the abutment. The most significant difference is observed in the stresses on the crowns and screws. When the stresses on the crown are examined, the use of PEEK crown reduces the stresses on itself and the use of PEEK abutment increases the stresses on the crown. Conclusions: The stress on the implant system can be changed through the usage of different prosthetic materials.

This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

This in vivo study evaluated the effect of graphene oxide and graphite coatings, coupled with the micro-arc oxidation (MAO) surface roughening technique, known for their mechanical strength, chemical stability, and antibacterial properties. The main objective was to assess the degree of improvement in osseointegration of titanium implants resulting from these interventions. In this study, 32 female rats were utilized and randomly allocated into four groups (n = 8 each): machined surface titanium implants (control), those roughened by the MAO method, those coated with graphene oxide-doped MAO, and those with a graphite-doped MAO coating. Titanium implants were surgically placed in the right tibia of the rats. Rats undergoing no additional procedures during the 4-week experimental period were sacrificed at the end. Then, the implants and surrounding bone tissues were separated and embedded in acrylic blocks for reverse torque analysis. Using a digital torque device, the rotational force was applied to all samples using a hex driver and racquet until implant separation from the bone occurred, with the corresponding values recorded on the digital display. Then, statistical analysis was performed to analyze the data. No statistically significant difference between the groups was observed in the biomechanical bone–implant connection levels (N/cm) (P = 0.268). Post-hoc tests were not required because no discernible differences were identified between the groups. Within the scope of this study, implants treated with the MAO method, along with those coated with graphene oxide- and graphite-doped MAO method, did not exhibit significant superiority in terms of osseointegration compared to machined surface titanium implants.

This study examined the effects of different levels of chronic restraint stress on bone–titanium implant contact in rats. This study included 32 adult female Sprague–Dawley rats. The machined surface titanium implants were surgically placed into the metaphyseal region of the rat tibias. Next, the rats were divided randomly into 4 groups, namely, control (CNT) (n = 8), low-restraint stress (LRS) (n = 8), medium-restraint stress (MRS) (n = 8), and high-restraint stress (HRS) (n = 8) groups. The rats in the CNT group received only the titanium implants surgically but did not receive any further treatment during the experimental period of 30 days. The rats in the LRS, MRS, and HRS groups were applied restraint stress for 1, 2, and 4 hours, respectively, daily for 28 days starting from day 2 after the surgery. At the end of the study period, the rats were sacrificed and their implants and the surrounding bone tissues were harvested for performing nondecalcified histological analysis. Moreover, blood samples were collected from the rats and were centrifuged for analyzing serum cortisol levels. Serum cortisol levels of the rats in the LRS, MRS, and HRS groups were higher than those of the rats in the CNT group (P < 0.05). Moreover, serum cortisol levels of the rats in the HRS group were higher than those of the rats in the MRS and LRS groups (P < 0.05). The extent of bone–implant contact was lower in the rats in the HRS group than in the rats in the CNT and LRS groups (P < 0.05). These data suggest that the application of 4-hour chronic restraint stress during the 28-day experimental period impaired the bone–implant contact.

Background: This study aimed to investigate the effects of systemic omeprazole treatment on the osseointegration of titanium implants. Material and methods: After surgical insertion of titanium implants into the metaphyseal part of rats’ both right and left tibial bones, the animals were randomly divided into three equal groups: control (n = 8), omeprazole dosage-1 (n = 8) (OME-1), and omeprazole dosage-2 (n = 8) (OME-2) and totally 48 implants were surgically integrated. The rats in the control group received no treatment during the four-week postoperative experimental period. In the OME-1 and OME-2 groups, the rats received omeprazole in doses of 5 and 10 mg/kg, respectively, every 3 days for 4 weeks. After the experimental period, the rats were euthanized. One rat died in each group and the study was completed with seven rats in each group. Blood serum was collected for biochemical analysis, and the implants and surrounding bone tissue were used for biomechanical reverse-torque analysis. In the biomechanical analysis, implants that were not properly placed and were not osseointegrated were excluded from the evaluation. Results: One-way analysis of variance and Tukey’s honestly significant difference test and Student’s t test were used for statistical analysis. The reverse-torque test (control (n = 9), OME-1 (N = 7), and OME-2 (n = 7)) analysis of biochemical parameters (alkaline phosphatase, calcium, phosphorus, aspartate aminotransferase, alanine amino transferase, urea, and creatinine) revealed no significant differences between the groups (control (n = 7), OME-1 (N = 7), and OME-2 (n = 7)) (P > 0.05). Conclusions: Omeprazole had no biomechanical or biochemical effects on the osseointegration process of titanium implants.