Question 19

Boiling it in water for 15 minutes is the next most effective method of sterilization.

Boiling a metal probe in water for 15 minutes effectively kills most bacteria, viruses, and other pathogens, making it a reliable method for sterilization when a steam sterilizer is not available.

A) washing it in soap and water

Washing a metal probe in soap and water is primarily a cleaning method rather than a sterilization technique. While it removes debris and some microorganisms, it does not reliably eliminate all pathogens, thus failing to achieve true sterilization.

B) heating it in a hot oven at 160°C for 20 minutes

Heating a metal probe in a hot oven at 160°C for 20 minutes can be effective for sterilization; however, it may not uniformly reach the necessary temperature throughout the instrument and is generally less practical for dental instruments compared to other methods.

C) boiling it in water for 15 minutes

Boiling the probe in water for 15 minutes effectively sterilizes it by killing a wide range of microorganisms, including bacteria and viruses. This method is simple, practical, and readily available, making it the next best option when a steam sterilizer is not accessible.

D) dipping it into a concentrated acid solution

Dipping a metal probe into a concentrated acid solution may damage the instrument and is not a common or accepted method for sterilization. While acids can kill some pathogens, they do not guarantee complete sterilization and pose risks of corrosion and harm to the equipment.

Conclusion

Boiling the metal probe in water for 15 minutes is the most effective alternative sterilization method available when a steam sterilizer is not an option. Other methods, such as washing with soap and water, heating in an oven, or using concentrated acids, either fail to achieve proper sterilization or pose practical challenges. Thus, option C is the best choice for ensuring the probe is adequately sterilized.