Dr. Martinsen, Dr. Patterson & Dr. Seelbach

Brent Patterson, D.D.S.

I am the founding owner of Texas City Family Dentistry and League City Family Dentistry. I was born and raised in Texas City and graduated from TCHS in 1989. My road to a dental education passed through a little town called College Station where I attended Texas A&M University GIG’EM. After a well-earned Biomedical Science Degree, I attended one of the top-rated dental schools in the country, UT Health Science Center Dental School in San Antonio. In 1997 I received my Doctor of Dental Surgery degree and headed back to the Bay Area.

The Texas City office opened for patients in August of 1999 and moved to it’s new much larger location in 2016. We opened our second office in League City in 2005 and moved to our own building in 2013 whosed design was inspired by my family’s travels in Italy. Lately I’ve devoted most of my time learning about Sleep Dentistry. It’s a new and exciting world where dental meets medical and our office is one of the few around who can help those patients unable or unwilling to use a CPAP machine for their sleep apnea.

Outside of dentistry, I enjoy working with the community via service organizations – TC/LM Jaycees, Texas City Foundation for the Future and the 9th District Dental Society and spending time with my family. My wife Michele is also a TC native who graduated from TCHS (’88) and Texas A&M (’92). She is a CPA and is the Manager of our Family Dentistry organization. Our oldest Samantha Is currently at Texs A&M Galveston working on her Bachelors in Marine Biology with a Minor in Diving and our boy Tucker is also at TAMUG working on his General Studies.

You will not find me on the golf course – I have enough frustrations during the week!!! I spend my ever-shrinking free time with the kids and or tinkering with new technology integration into dentistry.

Mark Martinsen, DDS

I was raised in Friendswood where I graduated from Friendswood High School in 1997. I then attended Texas A&M University where I received my Bachelors of Science degree in Biomedical Science with honors. After graduation, I studied at Texas A&M University-Baylor College of Dentistry where I received my degree of Doctor of Dental Surgery.

Since then, I have completed hundreds of hours of postdoctoral continuing education. I am dedicated to the newest advancements in cosmetic and general dentistry and keep up-to-date with the latest technologies and state of the art dental procedures.

After practicing for a number of years in Dallas, my wife, Stacey and I decided to move back to the Houston area to be closer to family. When I am not practicing my passion for dentistry, I spend most of my time with my two daughters, my son, and my wife. In my free time, I enjoy all sports and anything involving the water.


  • Bachelor of Science – Texas A&M University
  • Doctor of Dental Surgery – Texas A&M University Baylor College of Dentistry

Professional Memberships/Awards

  • American Dental Association
  • Academy of General Dentistry
  • American Academy of Cosmetic Dentistry
  • Texas Dental Association
  • Greater Houston Dental Society
  • American Academy of Esthetic Dentistry Award-AAED
  • Community Leadership Award-TAMBCD
  • Community Dentistry and Dental Public Health Award-AAPHD

Dr. Ann Seelbach

Dr. Seelbach is a native Texan who grew up in West Texas and has lived on the Gulf Coast for the past decade. She completed her Bachelor of Science at Texas A&M University and her Doctor of Dental Surgery at The University of Texas School of Dentistry. If Dr. Seelbach seems familiar to you, it might be from the four years she practiced as a dental hygienist at our office before leaving to pursue her dream of becoming a dentist.

When Dr. Seelbach is away from the office, she enjoys spending time with her husband, Andy, as well as sewing, reading, gardening, and traveling to new places. On beautiful Clear Lake sunsets you might find her walking her Great Dane, Stella.

League City Crew:

League City Assistants:

Joann, Inger, Sofia, Tiffany and Daniela

League City Front Office:

Syerice, Adriana, & Chatnie

League City Hygienists:

Alissa, Blaire & Ashley

Blaire Oney

Hello! My name is Blaire Oney. I grew up in Texas City, graduating from Texas City High School, and now live in League City. I attended college at Texas State University, graduating with a major in Biology and a minor in Chemistry. I studied Dental Hygiene at Blinn College and became a registered dental hygienist in 2011. I am married with 2 children and a chihuahua. I spend my free time with my family and friends. I love getting to know my patients and providing them with the best care possible!

Alissa Coatney

Hi! My name is Alissa. I’ve been practicing as a hygienist for the past 3 years. When I’m not working, I enjoy spending my time outside, traveling, and hanging out with close family and friends. I’m a proud wife, mama to a little boy, and dog mama to a sweet boxer. I love getting the opportunity to meet new people daily and look forward to seeing you and your family in the future!

Texas City Crew:

Texas City Assistants:

Nonnie, Jannet and Liliana

Texas City Front Office:

Shauna, Dioni and Stephanie

Texas City Hygienists:

Jessica, & Casey

Jessica Vastbinder

Hi, I’m Jessica. I’ve been a hygienist for 20 years. I’m so blessed that I have spent 17 years here with Texas City Family Dentistry. I truly love my work family and my patients. They are like a part of my extended family. When I’m not at work, I enjoy spending quality time with my family. I enjoy kayaking, biking, working out, motorcycle rides with my husband, and reading. I’m a proud mom of three boys, and a grandson. Can’t wait to see you !!!

Casey Rimmell

As a dental hygienist, my focus is on providing high-quality care to my patients and educating them on how to maintain good oral health. I am committed to making hygiene appointments a comfortable and positive experience. I am here to learn your dental history, listen to your concerns, and plan for a healthy future. Together, with the dental team, I will formulate patient
centered hygiene care plans that meet all of your dental needs.

During hygiene visits, I encourage patients to ask as many questions as possible. This allows me to personalize treatment and enable patients to be involved in their treatment.

I graduated from Lamar Institute of Technology with an Associate of Science Degree in Dental Hygiene in 2009. When I’m not working I enjoy spending time with my husband outdoors fishing, boating, or riding the Harley.