In Vitro Comparison of Loss of Torque between Gold and Titanium Alloy Abutment Screws in Dental Implants without Any Cyclic Loads

AIM

To find and compare the amount of screw loosening in gold and titanium alloy abutment screws without any cyclic load, this study was performed.

MATERIALS AND METHODS

A total of 20 implant fixture screw samples with 10 gold abutment screws from Osstem and 10 titanium alloy abutment screws from Genesis. Implant fixtures were placed into the acrylic resin using a surveyor to maintain the same path of insertion. Using a hex driver and calibrated torque wrench, initial torque was given according to the manufacturer's recommendation. One vertical and other horizontal lines were drawn over the head of the hex driver and resin block. Acrylic block position was standardized using a putty index in a fixed table and using a tripod stand a digital single-lens reflex camera (DSLR) camera was positioned with its horizontal arm facing the floor, as well as perpendicular to the acrylic box. Photographs were taken immediately after the application of the initial torque given as per the manufacturer's recommendation and 10 minutes after the initial torque. Re-torque of 30 and 35 N cm was given to gold and titanium alloy abutment screws respectively. Photographs were taken again in that same position immediately after re-torquing and 3 hours after re-torquing. The photographs were uploaded into the Fiji-win64 analysis software and the angulations were measured in each photograph.

RESULTS

Both the gold and titanium alloy abutment screws exhibited screw loosening after initial torquing. There was a significant difference in the amount of screw loosening between gold and titanium alloy abutment screws after initial torquing and no change in the abutment screw position after three hours of re-torquing.

CONCLUSION

Re-torquing of both gold and titanium alloy abutment screws after 10 minutes of initial torquing should be performed routinely for retaining the preload and minimizing the screw loosening even before loading the implant fixture.

CLINICAL SIGNIFICANCE

Gold abutment screws may have the ability to retain the preload better than the titanium alloy abutment screws after initial torquing, re-torquing may be necessary after 10 minutes to reduce the settling effect in a routine clinical procedure.

Systematic analysis of factors that cause loss of preload in dental implants

Screw loosening is the most common factor associated with dental implant failure. One of the major cause for screw loosening is the “loss of preload”. Several factors including screw geometry, material properties particularly stiffness, surface texture and condition of mating surfaces, degree of lubrication, rate of tightening, integrity of joint etc.

Influence of combinations of fenugreek, garlic, and black pepper powder on production traits of the broilers

Aim:

To study the effects of combinations of fenugreek (Trigonella foenum-graecum L.), garlic (Allium sativum), and black pepper (Piper nigrum) powder supplementation on production traits of broiler chickens.

Materials and Methods:

A total of 288 commercial broiler chicks were randomly assigned to 1-9 groups with 4 replicates each. An experiment was conducted in broilers with different feed formulations; control feed, with no added fenugreek, garlic, and black pepper powder; and 8 treatment groups receiving feed supplemented with different combinations of fenugreek, garlic, and black pepper powder. The individual broilers’ body weight and feed consumption were recorded and calculate the body weight gain and feed conversion ratio (FCR).

Results:

Broiler’s weight gain and FCR were significantly higher in groups receiving feed supplemented with garlic and black pepper powder combinations (p<0.01). Cumulative feed consumption was significantly higher in groups receiving feed supplemented with garlic and black pepper powder combinations (p<0.01).

Conclusion:

The combination of garlic and black pepper powder supplemented broiler feed fed groups showed higher production performance. The 5 g/kg garlic powder+1 g/kg black pepper powder and 10 g/kg garlic powder+2 g/kg black pepper powder significantly improved the weight gain and FCR.