The Smile Agency
Registered legal name: Karen Guinn DDS
1290 S Sunset Ave, West Covina, CA 91790
The registry record
- NPI
- 1548481211
- Registered as
- Type-2 organization (not an individual dentist's personal NPI)
- Dental categories
- Orthodontics, General, Oral surgery, Endodontics
- Taxonomy codes
- 122300000X (Dentist); 1223E0200X (Endodontics); 1223S0112X (Oral and maxillofacial surgery); 1223X0400X (Orthodontics and dentofacial orthopedics)
- Non-dental codes
- 302F00000X
- Practice location
- 1290 S Sunset Ave, West Covina, CA 91790
- Telephone
- (626) 856-1956
- NPI issued
- 1 May 2007 (19 years ago)
- Record updated
- 22 August 2016 (10 years ago)
- NPI status
- NPI active as reported by CMS 2026-08
- Metro area
- Los Angeles-Long Beach-Anaheim, CA (metropolitan area, Los Angeles County)
- State
- California (18,604 registered practices)
- Operator size
- 2 addresses registered under this organization name nationally
- Same address
- Katherine Forbes DDS, INC
- Map position
- Census address match at street level
- Snapshot
- NPPES data dissemination file, 10 August 2026
What the record tells you
The Smile Agency, the trading name of Karen Guinn DDS, is an NPI registry record for a dental organization at 1290 S Sunset Ave in West Covina, California 91790. CMS issued NPI 1548481211 on 1 May 2007, and the practice last updated its own entry on 22 August 2016. That was 10 years ago, so treat the phone number and the suite number as unconfirmed until someone answers.
It is registered under 4 dental taxonomy codes: Dentist (122300000X), Endodontics (1223E0200X), Oral and maxillofacial surgery (1223S0112X), Orthodontics and dentofacial orthopedics (1223X0400X). That puts it in 4 categories on this site, led by orthodontics. A practice that registers more than one category is telling CMS it does more than one kind of dental work at this address, which is why it has a page here rather than a row. The same registered name appears at 2 distinct addresses nationally. That is either a group practice or a name common enough that unrelated offices share it, so ask whether pricing is set locally or by a parent company. One other dental record shares the street address: Katherine Forbes DDS, INC.
West Covina holds 99 registered dental practices inside the Los Angeles-Long Beach-Anaheim, CA area, which has 8,403 in total on the California side and ranks 1st in the state. 9 of the West Covina records also register orthodontics, so this is one of several local options in that category. Across the metro the mix runs general dentistry 65.8%, dental clinic or center 21.5%, orthodontics 6.5%. The closest other registered practices are Katherine Forbes DDS, INC (0 miles, West Covina), Lin Ma DDS INC (0.1 miles, West Covina) and Nelly A. Parayno, D.M.D., INC. (0.1 miles, West Covina), with 2 more inside 0.1 miles.
On our figures a routine adult cleaning in California runs $130 to $200 cash and scaling and root planing $200 to $330 per quadrant, against a US average of $125. This practice's own prices are not in the registry and never will be: NPPES holds identifiers, not fees. Call (626) 856-1956 and ask for the cash price on code D1110, whether the exam and X-rays are included, and whether they run a membership plan if you have no insurance.
Nearest alternatives
The 5 closest registered dental practices to 1290 S Sunset Ave, straight-line distance. Rows without a link are listed on their metro page rather than having one of their own.
| Practice | City | Distance | Categories | Phone on the record |
|---|---|---|---|---|
| Katherine Forbes DDS, INC | West Covina, CA | 0 mi | General | (626) 939-0639 |
| Lin Ma DDS INC | West Covina, CA | 0.1 mi | General | (626) 966-4514 |
| Nelly A. Parayno, D.M.D., INC. | West Covina, CA | 0.1 mi | General | (626) 480-1598 |
| Friendly Endodontics INC | West Covina, CA | 0.1 mi | Endodontics | (626) 918-8700 |
| Eddie Kao DDS Family Dentistry | West Covina, CA | 0.1 mi | Dental clinic | (626) 962-5415 |
The benchmark to hold a quote from The Smile Agency against. California cost guide.
What to ask when you call
- The cash price for D1110, a routine adult cleaning, and whether the exam (D0120) and X-rays (D0274) are inside or outside that number.
- Whether you need scaling and root planing before a routine clean, and the per-quadrant price for D4341 or D4342 if so.
- Whether they run an in-house membership plan, and what it covers against what it costs a year.
- Whether they are taking new patients and how far out the next hygiene appointment is.
- The practice license, with your state dental board. An NPI is a billing identifier and proves nothing about licensing.
CMS NPPES NPI data file, August 2026, snapshot 10 August 2026. US federal public data (FOIA-disclosable, no charge). CMS NPI files. NPI registry records, status as reported by CMS in the August 2026 data dissemination file. NPPES is an identifier registry, not a license register: an NPI does not validate that a practice is licensed, accredited or currently open. Practices maintain their own NPPES entries. Every page shows the date the record was last updated; addresses and phone numbers are as self-reported and are not verified by us. This page describes a registry record. It is not a review, an endorsement or a check on The Smile Agency.
Price figures are our own, last verified April 2026. State averages are our estimates compiled from FAIR Health regional cost data and CMS Medicare fee schedules; the ADA discontinued its national Survey of Dental Fees in 2023, so no national fee survey exists. Treat them as a starting point and call two or three offices for an actual quote.