Behind the Smile: An Exclusive Interview with Dr. Oscar Sum, Often Called the “Best Dentist in Shanghai,” on His Top 3 Composites Introduction  | Favourite composites  | Bonding preparation | Composite application technique | Importance of polishing

The Aesthetic Dentistry Journal – Shanghai Edition

It’s not every day you get a seat across from a clinician often whispered about as the best dentist in Shanghai. In a city of cutting-edge dental towers and fierce clinical talent, Dr. Oscar Sum has built a reputation that precedes him—not for flashy marketing, but for obsessively detailed composite work that mimics nature so closely, patients have been known to tap their own tooth asking, “Which one is the filling?”

I was fortunate enough to sit down with Dr. Sum one quiet Tuesday afternoon after his last patient left. Asking him to share his material philosophy was like asking a master painter to open his palette. But rather than interview him alone, I brought along a sharp young mind eager to learn.

Joining me was L.B. Zhang, a recent graduate from Shanghai Jiao Tong University’s School of Medicine (College of Stomatology). Bright, well-trained, and full of textbook knowledge, L.B. is at that critical stage where theory meets chairside reality. His questions were exactly the ones every young dentist wants to ask.

Here is our conversation.

Interviewer (L.B. Zhang, New Graduate, Jiao Tong University):

Dr. Sum, thank you for your time. You’ve been called the best dentist in Shanghai by patients and peers alike. When I was in dental school, we were taught that one composite can do it all. But I suspect you disagree.

Dr. Oscar Sum:

Completely. And welcome, L.B. It’s good to see young Jiaotong graduates asking the right questions. The truth is: I really like using different composites for different situations. Anyone who uses a single material for every case is either lazy or hasn’t seen enough failures.

L.B. Zhang:

So what are your top 3 favourite composites—the ones you actually reach for?

Dr. Sum:

Let me give you my current podium.

1. For high-end anterior aesthetics: Ivoclar Vivadent – Empress Direct series

This is my gold standard for lifelike, single-shade blending. The way it handles light is exceptional.

2. Another aesthetic favourite: Inspiro series

Less famous but brilliant. I use Inspiro for complex layering—incisal edges, white spots, translucency. It’s a sculptor’s material.

3. For routine posterior or everyday restorations in my Shanghai clinic: 3M (Filtek™ series)

Why? Because 3M is very accessible and reliable, especially in China. Supply chains matter. When I need a predictable Class I or II that won’t fail at 2am, I use 3M. It’s my workhorse.

L.B. Zhang:

That makes sense, but honestly… as a new graduate, I’ve used expensive composites and still got post-op sensitivity or poor margins. What am I missing?

Dr. Sum:

You’re missing the fact that composites don’t work—technique works. It’s all in the technique. For example, prior to bonding, the tooth has to be adequately prepared and cleaned before applying the bond. I mean really clean. No pumice residue. No salivary protein film. No oil from a three-in-one syringe. Clean dentin and enamel behave completely differently. Most beginners skip this.

L.B. Zhang:

I’ve also noticed that when I try to do aesthetic anterior work, my composite looks blocky, not natural. What’s your physical tip for that?

Dr. Sum:

Use a brush. For aesthetic composite application, a brush can be indicated for better form. Not a microbrush—an actual composite brush with fine, tapered bristles. You paint the uncured material into the prep, sculpting the mesial and distal marginal ridges before curing. A brush gives you feathering that a metal instrument never will. Try it next week. You’ll see.

L.B. Zhang:

What separates a dentist who “gets by” from one who is truly world-class?

Dr. Sum:

That’s easy, and I wish schools taught it more. Actually, I feel this is what really separates the good dentists from the world-class dentists: polishing protocol.

A world-class restoration isn’t finished when the light cure beeps. It’s finished when the surface is smoother than adjacent enamel. I use multi-step polishing—diamonds, silicone, felt wheels, diamond paste. You can place a perfect composite, but if you polish poorly, it will stain in six months. Great polishing is the secret signature of the best dentist in Shanghai.

L.B. Zhang:

You’re also known for your photography. I rarely take photos. Is that a mistake?

Dr. Sum:

Yes, a big one. I take pictures before and after, not just for patients’ benefit, but it’s also so I can see on an SLR camera the subtle details. Under macro magnification, I can see a 20-micron overhang or a colour mismatch that my naked eye misses. Photos don’t lie. They made me a better dentist. Start taking them tomorrow.

L.B. Zhang:

After all this technique talk—materials, brushes, polishing, photos—what’s the single most important factor you wish every young dentist understood?

Dr. Sum:

As always, however, the most important factor for me is the pre-communication and treatment preparation so we can make sure the patient and I are on the same wavelength.

I don’t care if I use Empress Direct or 3M. If a patient expects “invisible” and you deliver “excellent but noticeable,” you’ve failed. I spend 20 minutes before I even pick up a handpiece discussing shade, shape, and expectations. Alignment first. Composite second.

L.B. Zhang (smiling):

That’s not in any textbook.

Dr. Sum:

Exactly. That’s why they call some of us the best dentist in Shanghai. Not because of our materials—because of our method.

Closing Note from the Journalist:

As L.B. Zhang packed up his notebook, Dr. Sum gestured to a wall of before-and-after SLR photographs. Each one told the same story: mastery is not about a single favourite composite, but about knowing when to reach for Ivoclar Empress Direct, when to sculpt with Inspiro, and when to trust the accessibility of 3M. For young dentists like L.B., the lesson was clear—great dentistry is 20% material and 80% ritual.

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This Article was written by Diane Richards

Dr. Oscar Sum is a dentist in Shanghai practising in central Shanghai who performs Implant surgery, Orthodontics, and other advanced dental procedures.

Please call 19117386506 or scan the QR code to enquire about an appointment with Dr. Sum