Why dental instruments are made of stainless steel?
Many types of tools are used to clean and care for teeth, including probes, mirrors, scrapers, dental burnishers and pressors. Mirrors help examine the patient’s mouth, and scrapers scrape to remove plaque and tartar. The polisher gives a final finish to the fill, smoothing out scratches left by other tools. The probe is used to find the cavity and pressure area of the tooth so that the restorative material can be placed. They have a variety of angles and pointed shapes, so the dentist can freely reach all sides of the teeth. A variety of materials are available to manufacture dental instruments, including stainless steel, carbon steel, titanium, and plastics. Important factors to consider when choosing a tool include strength and toughness of the material, weight, balance, ability to maintain sharp edges, and corrosion resistance.
Dental instruments should have enough strength and toughness to prevent their fracture and avoid stabbing accidents. Stainless steel offers the most suitable properties for each class of instrument. The high hardness of surgical stainless steel maximizes tip life and reduces maintenance time. Stainless steel tips have excellent toughness, scrapers and probes require sharp edges to reduce the pressure applied by the dentist, thus avoiding damage to the patient’s teeth or the tool itself. Blunt instruments are difficult to use, reducing the quality and accuracy of the operation and taking up more time for dentists.
As with all medical practices, cleanliness is a key factor to the safety and success of dental practices. Dental appliances need to be disinfected after each use, usually by means of high-temperature steam disinfection in an autoclave using dry heat sterilization or chemical steam pressure sterilization. Stainless steel is resistant to corrosion during any of these sterilized treatments and its inert surfaces are easily cleaned and disinfected. Scrapers are used to remove hardened dental plaque from the surface of teeth.
A widely used grade is AISI 440A, a high-carbon, 0.75% molybdenum hardened stainless steel. A manufacturer in California uses the Model 440A to manufacture high-quality dental and surgical instruments. According to the experience of the company’s metallurgists, this grade offers the best hardness, toughness and wear resistance of any stainless steel. Another top tool manufacturer in the United States uses 440A stainless steel to make durable, reliable, and high-quality instruments that enable dentists and technicians to achieve the best in medical practice and patient care.
A German dental instrument manufacturer manufactures probes using super duplex stainless steel containing 3% molybdenum. The super duplex stainless steel has high strength, good toughness and excellent wear resistance, ensuring that the tip of the instrument remains sharp for a long time. Sandvik, a stainless steel manufacturer, has offered a range of molybdenum-containing grades for medical and dental instruments – molybdenum-containing 4% precipitation hardening (PH) grade. It can be formed at low hardness, then heat-treated to reach final hardness in one step, and has better toughness than the hardened martensite grade, which requires more heat treatment steps.
