Filling Cost by Number of Surfaces: 1, 2, 3, and 4+ Surface Pricing
The number of tooth surfaces involved is the primary driver of filling cost. Each additional surface means more material, more time, and a higher ADA code. Understanding surfaces helps you read your treatment plan and verify your dentist's quote.
What "Surfaces" Means
Every tooth has five surfaces. When your dentist examines a cavity, they identify which surfaces are affected. The number of surfaces determines the ADA CDT code used for billing, which directly determines the price.
Mesial (M)
The side of the tooth facing the front of the mouth
Distal (D)
The side facing the back of the mouth
Occlusal (O)
The biting/chewing surface on top of the tooth
Buccal (B)
The side facing the cheek
Lingual (L)
The side facing the tongue
A "1-surface filling" affects only one of these areas. A "MOD filling" affects three surfaces: mesial, occlusal, and distal. More surfaces = larger cavity = more material = higher cost.
Amalgam Filling Prices by Surface
| ADA Code | Surfaces | Price Range | Example |
|---|---|---|---|
| D2140 | 1 surface | $75-$150 | Small cavity on the biting surface (O) |
| D2150 | 2 surfaces | $100-$200 | Cavity between two teeth (MO or DO) |
| D2160 | 3 surfaces | $125-$250 | Larger cavity spanning three sides (MOD) |
| D2161 | 4+ surfaces | $150-$300 | Extensive decay covering most of the tooth |
Composite Prices: Front Teeth (Anterior)
ADA codes D2330-D2335 apply to composite fillings on incisors and canines.
| ADA Code | Surfaces | Price Range |
|---|---|---|
| D2330 | 1 surface | $150-$250 |
| D2331 | 2 surfaces | $200-$350 |
| D2332 | 3 surfaces | $250-$400 |
| D2335 | 4+ surfaces | $300-$450 |
Composite Prices: Back Teeth (Posterior)
ADA codes D2391-D2394 apply to composite fillings on premolars and molars. Back-tooth composites typically cost $20-$25 more than anterior composites.
| ADA Code | Surfaces | Price Range |
|---|---|---|
| D2391 | 1 surface | $170-$275 |
| D2392 | 2 surfaces | $220-$375 |
| D2393 | 3 surfaces | $275-$425 |
| D2394 | 4+ surfaces | $325-$475 |
Front Teeth vs Back Teeth
Front Teeth (Incisors, Canines)
Easier access for the dentist, which can mean slightly lower fees. Front-tooth composites use materials optimised for colour matching and polishability. Insurance classifies anterior composites differently and covers them without the composite downgrade clause.
Back Teeth (Premolars, Molars)
Harder to access, requiring more time and effort. Back-tooth composites use stronger materials designed to withstand chewing forces. Posterior composite codes (D2391-D2394) typically cost $20 to $25 more than anterior codes. Insurance plans may apply the composite downgrade clause here.
How to Read Your Treatment Plan
Your dentist writes a code like D2392 on your treatment plan. Here is what it means:
If the charge on your treatment plan is significantly above the range shown, consider asking your dentist about the pricing or getting a second opinion. Regional variation can add 20-30% in high-cost areas like the Northeast or West Coast.
When Surface Count Changes the Restoration
1-2 Surfaces
Standard filling territory. Most small to medium cavities fall here. Cost: $75 to $375 depending on material.
3 Surfaces
Large filling. May need a build-up for structural support. Your dentist may suggest an inlay ($500-$1,200) for better long-term durability.
4+ Surfaces or Cusp Involvement
Inlay/onlay territory ($500-$1,500). If more than 60% of tooth structure is gone, a crown ($800-$3,000) is the better option.