The Cutting Edge: Why Sharp Instruments Matter More Than You Think

The Cutting Edge: Why Sharp Instruments Matter More Than You Think 

By Tabitha Acret 

In the ever-evolving field of periodontal therapy, one truth remains constant: sharp instruments are essential for effective care. Yet surprisingly, many clinicians overlook this foundational aspect of treatment. Blunt curettes, over-worn sickles, and poorly maintained universal scalers not only compromise outcomes—they put clinicians and patients at risk. It’s time to revisit the basics of instrument sharpening and redefine it not as a chore, but as a clinical priority. 

Dull Instruments Are Not Just Inefficient—They're Dangerous 

Let’s start with the obvious. A dull curette or scaler cannot remove calculus effectively. It requires increased lateral and apical pressure, more strokes, and more physical exertion. But the downstream effects go far beyond inefficiency. 

Using blunt instruments has been linked to: 

• Incomplete calculus removal 

• Burnishing of subgingival deposits 

• Soft tissue trauma 

• Root surface gouging 

• Patient pain and sensitivity 

• Slipping and operator loss of control 

• Clinician fatigue and repetitive strain injuries 

One study cited in Dimensions of Dental Hygiene describes instrument sharpness as a key factor influencing therapeutic success, operator fatigue, musculoskeletal injury, time management, and stress. In simple terms: if your instruments are dull, your body and your patients pay the price. 

“Burnished calculus becomes difficult to remove because the instrument’s cutting edge tends to slip over the smooth surface.” 
— Gehrig & Willmann, 2019 

The Physical Toll on Clinicians 

Blunt instruments increase gripping force and prolong scaling time—two major contributors to musculoskeletal disorders (MSDs). According to data, 60–93% of dental hygienists experience work-related MSDs, particularly in the hands, wrists, neck, and shoulders. These injuries are often preventable, and instrument sharpness is one of the simplest interventions. 

Repeated forceful strokes increase the risk of: 

• Carpal tunnel syndrome 

• Tendonitis 

• Trigger finger 

• Chronic neck and back pain 

Many of these conditions are career-ending. Investing time into sharpening instruments correctly isn’t just about scaling efficiency—it’s about professional longevity. 

“Blunt instruments increase gripping force, linked to carpal tunnel syndrome and tendinitis.” 
— Dimensions of Dental Hygiene, 2022 

A Matter of Patient Experience 

From the patient’s perspective, a dull curette can feel like a rake on soft tissue. This can lead to: 

• A dragging sensation during instrumentation 

• Prolonged tenderness post-procedure 

• Heightened sensitivity to air, water, or touch 

• Anxiety during future appointments 

Patients may not understand why a scaling appointment is painful—but they’ll often assume it’s the clinician’s technique. One painful visit is sometimes enough to erode trust or trigger non-compliance. 

The Science of Effective Debridement 

Effective periodontal therapy depends on thorough debridement—not just of supragingival plaque but also tenacious, embedded subgingival calculus. According to Carranza (2015), subgingival calculus can attach to cementum via mechanical interlocking, making its removal particularly challenging. 

Research shows that even after careful root debridement, 17–64% of subgingival calculus may remain. Even surgical intervention doesn't guarantee total removal, with 7–24% of deposits still found post-flap. These figures highlight just how precise and sharp our instruments must be. 

Burnished Calculus: The Invisible Enemy 

One of the most insidious consequences of blunt instrumentation is burnished calculus—smoothed-over deposits that remain attached but are nearly impossible to detect. These burnished surfaces resist removal and continue to harbor pathogenic biofilms, delaying healing and contributing to persistent inflammation. 

Burnished calculus is most often found: 

• In furcations 

• Around CEJs 

• In root concavities 

• Deep subgingival pockets 

“Burnishing of calculus may lead to delayed healing of the periodontal tissue and possible periodontal abscesses.” 
— Wilkins & Wyche, 2020 

The Ethical and Legal Imperative 

Blunt instruments don’t just hurt patients—they can get you into trouble. Failing to maintain functional instruments may be seen as clinical negligence, especially if it leads to: 

• Soft tissue trauma 

• Missed calculus contributing to disease progression 

• Instrument fracture or breakage 

• Unreported adverse events 

The Dental Board of Australia’s Code of Conduct reminds us that we have a professional and ethical obligation to provide care that minimises harm. Using a curette with a worn or rounded edge—especially when you know it’s not functioning properly—breaches that standard. 

 

How to Sharpen Smart: Instrument-by-Instrument 

Sickle Scalers 

Sickles have two cutting edges per working end. The terminal shank should be held at 12 o’clock, with the stone angled at 1 o’clock (100–110°). Sharpen both sides from heel to tip, and finish with a downward stroke to remove any wire edge. 

Gracey Curettes (11/12 & 13/14) 

Gracey curettes are area-specific, with only one cutting edge per end—the lower cutting edge. The terminal shank should be at 11 o’clock, and the stone at 1 o’clock. Sharpen only the tip and middle third, avoiding the heel and non-working edge. Sharpening the wrong edge destroys the built-in 70° angulation, rendering the instrument ineffective. 

“Sharpening the wrong side—typically the non-working edge—compromises the instrument’s design. Mistakenly sharpening the upper edge ruins the offset angle.” 
— Gehrig & Willmann, 2019 

Universal Curettes 

Universals have two cutting edges that require symmetrical sharpening. Terminal shank at 12 o’clock, stone at 1 o’clock (right edge) and 11 o’clock (left edge). Avoid over-thinning the toe or flattening the blade—these changes reduce adaptability and cutting power. 

 

Common Sharpening Mistakes to Avoid 

❌ Sharpening the wrong edge on Graceys 
❌ Over-sharpening the heel 
❌ Flattening the rounded toe 
❌ Sharpening past the middle third 
❌ Using excessive force or the wrong stone 
❌ Continuing to sharpen an instrument that should be retired 

 

When to Retire an Instrument 

Even with perfect sharpening, curettes and scalers don’t last forever. If you’re finding that: 

• Your instrument looks shortened 

• The shape is distorted or asymmetrical 

• You’re still struggling to remove deposits 

• You’ve already reshaped the toe… 

…it’s time to replace it. 

“A curette that’s been shortened too far no longer performs its job and may put your patients and your reputation at risk.” 
— Wilkins, 2020 

In high-traffic hygiene departments where kits are used multiple times a day, instruments may need to be replaced every 6–12 months. Build this into your preventative care department’s annual budget. 

 

 

The Financial Argument: Sharpening Saves Money— 

Until It Doesn’t 

Instrument sharpening extends the life of your tools and can delay replacement. But repeated sharpening of an already-compromised instrument wastes time and compromises care. Investing in quality instruments and maintaining them properly is more cost-effective in the long run than struggling through appointments with underperforming tools. 

Consider: 

• Instrument cassettes and  sharpening guides 

• Sharpen-free technologies (e.g. LM DualGraceys XP) 

These options can reduce sharpening frequency while maintaining precision. 

 

A Sharpening Culture in Every Clinic 

Creating a culture of sharpening and instrument maintenance starts with: 

• Routine sharpening protocols (e.g., weekly or post-each-use) 

• Sharpening logs to track instrument condition 

• Clinical audits on blade sharpness and shape 

• In-clinic training on sharpening techniques 

• Team accountability—every clinician is responsible for their tools 

 

Final Thought: Don’t Graduate and Retire With the Same Instruments 

Too many clinicians continue to use the same instruments they had in dental school—10 years later. In reality, sharpness begins to degrade within weeks of regular use. Our patients deserve better. So do our hands, our backs, and our standards of care. 

As dental professionals, we don’t just scale—we diagnose, assess, and intervene in diseases that affect systemic health. If our tools are dull, our message is too. 

It’s time to stay sharp—in every sense of the word. 

 

References 

• Gehrig, J.S., & Willmann, D.E. (2019). Foundations of Periodontics for the Dental Hygienist (5th ed.) 

• Wilkins, E.M., & Wyche, C.J. (2020). Clinical Practice of the Dental Hygienist (13th ed.) 

• Neuman, T. (2022). Instrument Maintenance and Sharpening. Dimensions of Dental Hygiene, 20(9), 34–37 

• American Academy of Periodontology. (2015). Comprehensive Periodontal Therapy Statement, J Periodontol, 86(7), 835–838 

• Chapple, I.L.C., et al. (2015). Primary prevention of periodontitis: managing gingivitis. J Clin Periodontol, 42(Suppl 16): S71–S76 

• Dental Board of Australia. (2020). Code of Conduct for Registered Health Practitioners 

• Carranza’s Clinical Periodontology (12th ed.)