Manuel Castillo, DDS
Board Certified Pediatric Dentist


The American Board of Pediatric Dentistry is a specialty organization that administers a very thorough set of exams to qualified specialists. This is the highest accreditation level they can achieve.


You’ll remember Dr. Mani because of his calm personality and his eagerness to make kids smile, be it with a silly joke or even a magic trick —something he learned from his father.

Dr. Manuel Castillo is a Board Certified Pediatric Dentist. He is a 1991 graduate from Marquette University School of Dentistry. In addition to his extensive hands-on experience as a general doctor of dentistry, Dr. Castillo also thrived in academics. He worked as a full time assistant professor at Marquette University School of Dentistry, and held faculty appointments at Northwestern University Dental School in Chicago and at the University of Colorado, School of Dental Medicine.

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After 12 years in private practice and academics, Dr. Castillo was commissioned as dental officer in the U.S. Army in 2000. Major Castillo’s first assignment was in beautiful Monterrey, California, where he met his wife Claudia. At that time he was selected for pediatric specialty training and earned his Pediatric Dentistry Certificate from Baylor University School of Dentistry at Dallas in 2005. In September of 2006 Dr. Castillo became a Diplomate with the American Board of Pediatric Dentistry, and in May 2007 he became a Fellow with the College of Diplomates of the American Board of Pediatric Dentistry.

Lieutenant Colonel Castillo finished his military career with a three-year assignment in Germany as Chief of Pediatric Dentistry in 2008. After proudly serving in the U.S. Army for eight years, Dr. Manuel Castillo decided to establish his roots in Texas where he has served his patients in two private Children’s Dental practices. After almost 24 years of both general and pediatric dental experience, in 2015, Dr. Castillo decided it was time to venture in a solo practice where he could create a close and caring relationship with his young patients and their parents.

Dr. Castillo has his hands full with his three handsome boys, Mikhail, his oldest has already made him a grandfather while making a successful career in sales, Marcos goes to Coppin State University in Baltimore, where he also plays baseball, and Mattías, his youngest sweet boy. Marina is his young ballerina, and Claudia is his beautiful wife and office manager.

Dr. Castillo’s extensive experience and skills continue to earn his patients’ trust. Children and parents love his fun personality and gentle touch.


Andrea Galindo


Andrea is from a small border town called Del Rio. After graduating high school in 2014, she moved to San Marcos, where she attended Texas State University and Graduated from Concorde Career college in 2018 to become a Registered Dental Assistant. Andrea is very outgoing and bubbly. She has a passion for working with kids and loves the energy and joyfulness the kids bring her. Andrea is also the director/ Head coach for Texas Storm Athletics and has won numerous national championships. She enjoys working her cheer teams and building character and a cheer family bond with the kids both in cheerleading and at Happy.

Dr. Cristina Leon-Pineda


Dr. Leon is a caring and gentle mom of a beautiful girl. She is also very smart: her dental degree is from Puerto Rico, where she graduated Cum Laude; and her Dental Pediatric Specialty is from UTHSA, where she is a faculty member. 

Dr. Leon is a very skilled Pediatric Dentist. Before becoming a specialist, she practiced general dentistry for five years. During her specialty training at UTHSA, she excelled in her class and was immediately offered a faculty position at the dental school right after graduation. She has also been a speaker in dental conferences. She works part-time at Happy and the rest of the time as at UTHSA preparing the new generations of pediatric dentists.

Our young patients enjoy her empathy, caring demeanor, and professionalism.

Claudia Decet-Castillo


Claudia Decet-Castillo is Dr. Castillo’s wife, and as a mother, she loves children. She wants to make sure that our young patients have the best possible dental experience. She has worked as an educator, a translator and conference interpreter, also as a corporate trainer and office coordinator. She is fluent in English, Spanish and Italian. Outside the office, Mrs. Castillo enjoys, gardening, doing art projects with her children and even reviving old furniture by painting it with fun-bright colors.

Yamilka Encarnación


You will enjoy Yami’s friendly personality, especially when it comes to explaining your treatment plan in the easiest terms. She offers over 15 years of dental insurance experience. She loves being able to help patients completely understand their treatment plans. She also enjoys the opportunity to educate them on how proper oral health and maintenance can help prevent future health issues. Yami is a proud mother of six beautiful children. In her free time, she really likes being outdoors, working out, cooking and watching her children participate in many activities. She will be happy to help you find answers to any questions or concerns you might have about your insurance and/or treatment plan.

Lourdes Colon


The first thing you’ll notice about Lulu is her big, easy smile. She’s married and has two children. Originally from Puerto Rico, she has been in San Antonio since 2015. She earned her Business Administration degree in Puerto Rico, after which she worked in the dental field starting in the front office, then as a dental assistant and finally as office manager —all adding up over 20 years of experience. Once she arrived in San Antonio, she went back to school and became a Registered Dental Assistant. She loves working in the dental field, and especially with children. For her, children are pure joy, love, and fun. In her free time, she enjoys music, dancing, cooking and doing crafts. Working at Happy suits her well as she expresses her love for the little ones, helps them to trust the dentist, and will do everything possible to make your child’s visit a happy one.

Angelica Avina


Angelica is originally from Mexico. She moved to Laredo, Texas with her family in 2002 when she was just a teenager. After graduating from college, she moved to San Antonio to continue her studies. In 2016, she graduated from the University of Incarnate Word as a Dental Assistant. She loves working with children and watching them smile. In her free time, Angelica enjoys spending time with her family. She is both very knowledgeable when it comes to insurance coverage details and highly skilled as a clinician. You will enjoy her calm and professional demeanor.

Sara Cancel


Mrs. Cancel is the happy mother of a handsome boy. She is originally from Puerto Rico, where she went to Art School and Dental Assisting School. She moved to San Antonio with her husband in 2014. She loves working in dentistry. Her motto is to always give her best. In her free time, Mrs. Sara enjoys painting and singing. At Happy Pediatric Dentistry, we all like her sweet, happy and caring disposition. She is grateful for her parents as they taught her to be respectful towards others and she always wishes the very best for them.

Sirena Segura


Sirena is originally from California and moved to Kerrville, Texas in 2008. Right after high school she moved to San Antonio to attend college, eventually graduating from dental assisting school in 2016. She loves working with children and helping maintain bright, beautiful smiles. In her free time, she enjoys dancing, knitting, and trying exotic foods.


We understand that parents, at times, are unable to take care of their children’s dental needs during regular business hours. That’s why we are happy to offer services on Saturday morning and have an extended day on Wednesday until 7pm.