The Biomechanical Investigation of Osseointegration Levels in Titanium Implants Simultaniously Placed with Different Bone Grafts

BACKGROUND

Dental implant-supported prostheses have been scientifically accepted and have been a common treatment choice in the case reconstructing of partial or total tooth loss. In additon, bone grafts (alloplast, xsenograft, allograft) are frequently used in implant and sinus lift surgical procedures.

AIM

The aim of this study is to investigate the bone-implant osseointegration levels of titanium implants simultaniously placed with different bone grafts.

MATERIALS AND METHODS

In the study, 32 female S. Dawley rats were divided into four groups. In the control group (n = 8), turned surface implants with a 2.5 mm diameter and a 4 mm length were placed in the tibia of the rats without the use of a graft material. In the experimental groups, bone cavities were opened in the tibias of the rats and a synthetic (alloplast) graft (n = 8), human allograft (n = 8), and bovine xsenograft (n = 8) were placed simultaniously with a 2.5 mm diameter and a 4 mm length turned surface titanium implants. The cavities in the experimental groups were opened with a 4 mm diameter and a 5 mm length. After 8 weeks of recovery, all rats were sacrificed at the end of the experimental period. The implants and surrounding bone tissue were removed. The removed tissue was subjected to biomechanical analysis in order to evaluate bone-implant osseointegration and peri-implant new bone formation. The Kolmogorov-Smirnov test, Kruskal-Wallis test, and Mann-Whitney U-test were used in the study. Significance was evaluated at the P < 0.05 level.

RESULTS

In the biomechanical analyses, it was determined that there was no statistically significant difference between the control group and the other three groups in which different graft materials were applied in terms of bone-implant osseointegration (P > 0.05). In other words, in the biomechanical analyses, no statistical difference was found between any of the groups.

CONCLUSIONS

As a result of this study, it can be thought that different graft materials can be successfully used in peri-implant-guided bone regeneration and may be an alternative to autogenous grafts.

Effects of Systemic Propranolol Application on the New Bone Formation in Periimplant Guided Bone Regeneration

Objectives

The aim of this experimental animal study was to evaluate the effects of systemic propranolol on new bone formation in peri-implant bone defects.

Material and Methods

Implant slots were created 4mm long and 2.5 mm wide. After the titanium implants were placed in the sockets, 2 mm defects were created in the neck of the implants. Bone grafts were placed in these defects. Then the rats were randomly divided into three equal groups: control (n = 8), propranolol dose-1 (PRP-1) (n = 8), and propranolol dose-2 (PRP-2) (n = 8) groups. In the control group, the rats received no further treatment during the eight-week experimental period after the surgery. The rats in the PRP-1 and PRP-2 groups were given 5 mg/kg and 10 mg/kg propranolol, respectively, every three days for the eight-week experimental period after the surgery. At the end of the experimental period, the rats were euthanized. Blood serum was collected for biochemical analysis, and the implants and surrounding bone tissues were used for the histological analysis.

Results

There were no significant differences in the histological analysis results and the biochemical parameters (alkaline phosphatase, calcium, creatinine and phosphorus) of the groups (P > 0.05). Also, in the test groups, there was numerically but not statistically more new bone formation detected compared with the controls.

Conclusions

Within the limitations of this study, propranolol did not affect the new bone formation in peri-implant defects.

Effects of local application of the ankaferd blood stopper on osseointegration in three different surface titanium implants

Objective

Researchs of the effects of ankaferd blood stopper (ABS) on bone healing metabolism have revealed that it affects bone regeneration positively. The exact mechanism by which this positive effect on bone tissue metabolism is not known. The aim of this study is to biomechanic and biochemical analysis of the effects of the local ABS application on osseointegration of 3 different surfaced titanium implants.

Material & Methods

Spraque dawley rats were divided machined surfaced (MS) (n ​= ​10), sandblasted and large acid grid (SLA) (n ​= ​10) and resorbable blast material (RBM) (n ​= ​10) surfaced implants. ABS applied locally during the surgical application of the titanium implant before insertion in bone sockets. After 4 weeks experimental period the rats sacrificed and implants with surrounding bone tissues were removed to reverse torque analysis (Newton), blood samples collected to biochemical analysis (ALP, calcium, P).

Results

Biomechanic bone implant contact ratio detected higher in SLA surfaced implants compared with the RBM and controls (P ​< ​0,05). Phosphor levels detected lower in RBM implant group compared with the controls and SLA (P ​< ​0,05). Additionally; phosphor levels detected highly in controls compared with the RBM implants.

Conclusion

According the biomechanical parameters ABS may be more effective in SLA and RBM surfaced implants when locally applied.

Biomechanical and biochemical evaluation of the effect of systemic application of omeprazole on the osseointegration of titanium implants

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.

Pentoxifylline and electromagnetic field improved bone fracture healing in rats

Background

The aim of this study was to evaluate the effects of a phosphodiesterase inhibitor pentoxifylline (PTX), electromagnetic fields (EMFs), and a mixture of both materials on bone fracture healing in a rat model.

Materials and methods

Eighty male Wistar rats were randomly divided into four groups: Group A, femur fracture model with no treatment; Group B, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection; Group C, femur fracture model treated with EMF 1.5±0.2 Mt/50 Hz/6 hours/day; and Group D, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection and EMF 1.5±0.2 Mt/50 Hz/6 hours/day.

Results

Bone fracture healing was significantly better in Group B and Group C compared to Group A (P<0.05), but Group D did not show better bone fracture healing than Group A (P>0.05).

Conclusion

It can be concluded that both a specific EMF and PTX had a positive effect on bone fracture healing but when used in combination, may not be beneficial.

A comparison of the effects of methylprednisolone and tenoxicam on pain, edema, and trismus after impacted lower third molar extraction

Background

The aim of the present study was to compare the effects of preemptive intravenous tenoxicam and methylprednisolone administrations on extraction of impacted third molars.

Material/Methods

This was a placebo-controlled, randomized, double-blind, clinical trial. A total of 60 adult patients ages 18–40 years with the complaints of impacted third molar teeth were included in the study.

Results

The postoperative swelling ratios (p<0.05) and pain scores (p<0.05) were significantly better in both study groups than in the control group and there was no statistically significant difference between methylprednisolone and tenoxicam groups with regards to the edema and pain relief.

Conclusions

Preoperative administration of 80 mg methylprednisolone achieves better control of trismus than tenoxicam without any significant differences in edema and pain control in impacted third molar teeth extraction.

Effects of ascorbic acid and lighting schedule on tibiotarsus strength and bone characteristics in broilers

Abstract. This study was conducted to determine the effects of two lighting programs (continuous program; 24 h lighting or intermittent; 12 h daylight followed by three cycles of 1 h lighting and 3 h dark program during the night period) and three different ascorbic acid (AA) supplementations (0, 200 and 400 mg/l, added to water) on some serum parameters, ash content and mechanical properties of tibiotarsus. For this purpose one-day-old male commercial (Ross PM3) broiler chicks (n=600) were divided into 6 treatment groups (2×3) with random replicates (4 replicates per treatment). At the end of 6 weeks, intermittent lighting program negatively influenced serum alkaline phosphatase (ALP) and calcium (Ca) levels (P<0.001) while continuous lighting program had positive influence on bone ash, Ca and phosphorus (P) content (P<0.001). The AA addition decreased serum inorganic phosphorus (Pi) level and positively affected bone chemical characteristics (P<0.001). On the mid-section of the bone, although intermittent lighting had positive effect on bone mechanical parameters (P<0.001), no remarkable effect was observed by AA supplementation. The results of the present study suggest that interaction of intermittent lighting and AA supplementation (200 mg/ l) may have positive effect on chemical composition and mechanical characteristics of bone in broilers.

Effects of amylin on bone development and egg production in hens

Amylin is a member of the calcitonin family of hormones cosecreted with insulin from the pancreatic beta-cells that can act as an osteoblast mitogen and as an inhibitor of bone resorption in mice and humans. The aim of this study was to investigate the role of amylin on bone formation and some egg parameters in hens. The study was performed in 60 hens aged 10 wk. Thirty hens constituting the treatment group were s.c. injected with amylin at a 75 microg/kg dose every other day. The remaining hens were used as the control group. Five birds from the treatment and control groups were slaughtered at 14, 16, 18, and 20 wk of age and serum and bone parameters were compared between the treatment and control groups. The remaining 20 hens were fed without any amylin injection until 35 wk. All hens at the end of the 35th week were slaughtered and then serum, bone, and egg parameters were assessed. In the treatment group, bone calcium levels increased, whereas serum calcium levels decreased. This dose of amylin also increased the cortical width of tibiotarsuses in hens. Eggshell thickness was found thicker in the treatment group than in the control group. Overall, the results of this study suggest that amylin may stimulate the bone and eggshell quality by increasing calcium uptake from the bloodstream and may influence the sustainability of yield in hens.

Erythrocyte potassium, sodium and glutathione concentrations and their relationship with reproduction, body weight and fleece weight traits in Awassi sheep

Abstract. Relationship between erythrocyte potassium (Ke), erythrocyte sodium (Nae) and blood glutathione (GSH) concentrations and production/ reproduction traits were investigated in Awassi sheep. Thirty healthy sheep subjected to analyze for phenotypic and gene frequencies of Ke, Nae and GSH concentrations. Correlation between these parameters and production/ reproduction traits such as greasy fleece weight, milk production, birth rate, single and twin birth rate and body weight were calculated. A positive correlation was found between birth rate and mean Ke concentration (r=0.481, P<0.008) and Nae concentration (r=−0.454, P<0.013). Another correlation between GSH concentration and greasy fleece weight (r=−0.368, P<0.049) and milk production (r=0.379, P<0.050) parameters was also evidenced. These suggest that Ke, Nae and GSH concentrations may be included in the metabolic profile testing parameters.