Dr. Kosta's Dental Office, Konstantinos Proussaefs, DDS, Inc

Fantastic experience: Dr. Kosta, and staff are always friendly and professional. Shirley was fantastic.

Fantastic experience: Dr. Kosta was very gentle and all office staff were very professional and kind!

Fantastic experience: Great experience. Very professional office and staff. Thank you !

Negative experience: BEWARE, they dont back up their work. i had a few chipped teeth repaired and 5 months later the corner broke off one while eating doritos. i reached out and notified them but was told that even if it happened the day after the repair, i would have to pay the full amount to fix the tooth again. i understand i was eating doritos but they are not tough chips to eat. she didn’t stop to ask anyone, or take a beat and say, “let me see what we can do for you”. just a hard no. in the past i had a similar issue with a different tooth from eating and that dentist repaired it at no additional cost and has been solid for years. which is very disappointing because in the past i came here for two+ years before returning as a patient last year. i was asked to make an appointment to have it fixed and pay again but no thank you. ill be taking my business elsewhere.

Fantastic experience: Had a great visit was taken care by Dr Kosta very satisfied

Fantastic experience: Best Dentist in California. I drive 30 minutes just to see him. The staff is kind and responsive. No sales pressure at all. I would recommend him to everyone I know

Fantastic experience: Dr. Kosta is an excellent and highly skilled dentist, that genuinely cares about his patients dental health. I am a doctor myself and I know good quality care when I experience it. He is the only dentist I would let work on my wife and I. His office is clean and his staff is very professional.

Fantastic experience: Dr. Kosta is the best I always have a good experience coming here!!

Positive experience: The lady at the front desk needs to smile more, she always looks mad, other than that everyone is amazing!

Fantastic experience: Awesome dentist! Dental hygienist very gentle and personable!! Always a good experience!

Fantastic experience: If you’re looking for a dentist, I highly recommend Dr Kosta. He and his staff are great! Talia did a great job. Excellent service and very professional.

Fantastic experience: ALWAYS DO AMAZING WORK AND GREAT CUSTOMER SERVICE Dr. Kosta is so kind and knowledgeable. He keeps my smile nice and white Stacy at the front desk helped me schedule and when I was sick she also helped me get rescheduled

Fantastic experience: The staff is very friendly and professional. I never have to wait with my appointment, always timely. Dr. Kostas is the best dentist I've ever gone to see. He is so nice and cares about his patients very much!

Fantastic experience: very nice office with a very caring dr and kind and professional staff

Fantastic experience: Thank you for the nice vibe. Looking forward to coming in tomorrow.

Fantastic experience: The office is great ! Very friendly . Dr. Kosta does great work practically painless . Highly recommend.

Fantastic experience: I have been going to Dr. Kosta for many years, and he does an excellent job. Very happy with their service.

Negative experience: The dental hygienist was fair at best. At times was on autopilot and painfully poked me with a very sharp instrument. Her requests were unclear and not specific. She did not introduce herself by name. She did not rinse even once during scaling and only rinsed by request on polishing.

Fantastic experience: Dr Kosta is a very kind Dr and his office personnel are very polite and kind also.

Fantastic experience: Dr. Kosta and his staff are always welcoming. They provide professional, gentle treatment and make the dental experience comfortable.

Fantastic experience: After losing a crown in the evening, I called Dr. Kosta's office the following morning at 7am and they fit me in. How nice it is to have a dentist that goes out of his way to accommodate his patients

Fantastic experience: The staff is always friendly and Dr. Kostas is amazing.

Fantastic experience: Dr. Kosta is not only the nicest and most professional dentist I’ve been to, but the best. He removed my wisdom teeth quickly and painlessly, and because I told him I’m squeamish about that kind of stuff he made sure to keep me distracted. Wonderful dentist and staff!

Fantastic experience: I was referred here from friends, and I can tell why they raved! Everyone in the office is so kind and efficient. Happy to have a new dental care team that really listens and have great energy. Definitely makes the dentist less of a pain (pun intended!).

Fantastic experience: Dr. Kosta ans his staff consistently provide amazing service. I highly recommend Dr Kosta for all your dental needs.

Fantastic experience: Dr Kosta is always so gentle and kind. He also explains what he is doing before he does it, which is a huge help for me because I am a total chicken I highly recommend him!

Fantastic experience: Great office, friendly and knowledgeable. Dr. K is a total professional, very nice, good listener and willing to give options on treatments. I highly recommend this dentist and his office staff.

Fantastic experience: Dr. kosta and staff are amazing. He is a true G. Took care my chipped tooth the next day first thing in the morning. I was able to make it to work with no issues.

Fantastic experience: Dr. Kosta’s office always leaves me heading out the door with a smile. His assistant Sofia was so kind and gentle during all of my X-Rays. Dr. Kosta always has such great attention to detail. Every experience I've had here has been far above the typical standard! Thank you Dr. Kosta and Staff!!

Fantastic experience: By far barnun the best. I have ever been to in my life. He does a great job highly recommend him. Oh, and by the way, his staff very professional, everyone in the. Office does a great job.

Fantastic experience: Dr Kosta and his team are amazing. He has been caring for my kids since they were little and they are in the best hands. It is obvious that he truly cares for his patients.

Fantastic experience: Dr Kosta is the only dentist I trust. I’ve been seeing him since 2010.

Fantastic experience: I’ve been a patient here for 16 years, Dr Kosta and his staff are the best!

Fantastic experience: I’ve been going here for 10 years and Dr. Kosta is very thorough and kind. I had my wisdom teeth removed by him and my recovery was flawless. I would recommend him to anyone looking for a new dentist

Fantastic experience: The staff are all amazing. No wait time. My daughter who originally recommended Dr. Kosta to me raves about him and the amazing job he did to restore her daughters front tooth.

Fantastic experience: Dr. Kosta saved me from First Street dental. First Street consists of mostly people from LosAngeles and are part of a subsidiary there. They charged me thousands right before Xmas and broke the crown without telling me so I went home to find the damage. Dr. Kosta not only made a perfect crown but fixed their damage to the original tooth and I was in and out. Go here if you want the best.

Fantastic experience: Dr Kosta and staff are excellent. Dr Kosta makes the process very easy and he is so sweet.

Fantastic experience: Got the second half of my crown done today, it looks great! Basically painless. Dr. Kosta is the best. Great team too!

Fantastic experience: Dr. Kosta and his entire staff are excellent. I hated going to the dentist before I was referred to him. I had waited years because of dental PTSD and was never judged, they were gentle, and I was made to feel comfortable being there. That was 3 years ago and I will never use another dentist. They also listen to your individual financial needs and will help you stick to your budget while still maintaining proper dental care. Go see him you won’t regret it!

Fantastic experience: I love this place. I first came here a few years ago completely nervous and apprehensive. Dr. Kosta and his staff are so caring and wonderful. I love how each room has nature shows on the monitor. Definitely recommend to anyone. Just had another 6 month appointment today and everyone was fantastic, as usual.

Negative experience: Im very disappointed with the way I was treated by the receptionist today. I called to let the office know I was running late to my appointment, and instead of being understanding or offering solutions, she was extremely rude. She flat-out said “no,” refused to reschedule me, and never took the time to go over any other options. What made this worse is the attitude she showed when it came to my military insurance. As a service member, I felt disrespected and dismissed—something I’ve never experienced at other dental offices. Professionalism and basic courtesy were completely lacking. I truly value good dental care and respect the providers, but the way patients are treated at the front desk sets the tone for the entire office. Unfortunately, today’s experience left me feeling unwelcome and undervalued.

Fantastic experience: The best dentist I’ve ever had. The dental hygienist is extremely gentle and thorough. No poking or prodding. The staff is incredibly friendly and helpful. Dr Kosta is fantastic. Couldn’t recommend them enough.

Fantastic experience: Dr Kosta is Amazing. He is so nice ,super gentle kind. He is a Gem.Thank you for bringing back my smile. I am a 12 year cancer survivor. The treatment killed my teeth from being sick. I am.blessed to be alive and so.happy I did.it ! Before and after photos attached . I highly recommend Dr Kosta for your dental care. He truly cares.

Fantastic experience: Staff and Dr. Kosta are always very nice and friendly. I have never had to wait more than 2-3 minutes before being called into the treatment room! It’s a wonderful feeling to look forward to going to the dentist after decades of being a panican!

Fantastic experience: From the moment you walk in, the front desk team sets the tone with kindness, efficiency, and genuine care. The hygienists are thorough, gentle, and always take the time to explain what they’re doing, which makes every visit feel reassuring. And Dr. Kostas is exceptional—skilled, attentive, and clearly committed to patient comfort and long-term dental health. I couldn’t ask for a better experience. Highly recommend!

Fantastic experience: Dr. Kosta, his assistants and office help are wonderful! They are welcoming, efficient and made my 103 year old dad comfortable and at ease. Dr. Kosta did a tooth extraction on dad’s first visit, after taking X-rays, without making us come back for the procedure another day considering our situation. They went beyond the call of duty! So thankful!

Positive experience: The staff over all is great. I have been going to this office for years. This was the first time I have felt like had a hygenist who abreviated my teeth care. Bounced around when scraping my teeth and then felt like the floss and polish was abbreviated.

Fantastic experience: Such a swift and easy appt. 10/10 recommend Dr Kosta and his staff.

Fantastic experience: Great staff! Doctor Kosta is sweet and takes his time. Everyone there is a pleasure :)

Fantastic experience: Friendly, gentle, quick, and answered all my questions thoroughly. Haven't heard of a better dentistry than this.

Fantastic experience: Had a great fist visit and cleaning with Dr. Kosta. Very pleasant staff and good atmosphere all around. Dr. Kosta has a very reassuring manner that conveys high trust and confidence. Second visit was even better than the first. Dental hygienist Nicole is so good I didn't even realize I was getting a cleaning, but when she was finished my teeth felt the cleanest they've ever been. Dr. Kosta gave me a thorough exam and we discussed the possibility of using a night guard to prevent me from biting my inner cheek at night. I can't enough about how great this office is. Now the third or fourth time confirming great experience, and none of my teeth have fallen out! LOL. Nicole is the best! Dr Kosta is our favorite family dentist!

Fantastic experience: Dr Kosta’s Office staff are so professional, honest, and kind. I really enjoy seeing them. My husband has been going to them since he was younger. Dr. Kosta is very friendly, professional and knowledgeable about dentistry. He’s never pressed any treatment and always lets us decide what’s best for our family. So thankful my husband recommended him as our new dentist after we married.

Fantastic experience: As always super professional and attentive. Team is gracious and pleasant to talk to, always checking in on your comfort. Quick in and out thorough cleaning visit.

Fantastic experience: Excellent dentist and staff. Everyone is super friendly and efficient. Dr. Kosta is the best dentist I have ever been to. He is honest and doesn't recommend treatments unless you need them. The office is well run and organized. They don't overbook so you know you will get in at your appointment time.

Fantastic experience: Everyone is very professional and friendly. They make you feel very comfortable. The hygienists clean your teeth with no discomfort or pain. The girls at the front desk are very accommodating and friendly, and Dr. Kostas is very knowledgeable, kind and thorough. Its a great office all around.

Fantastic experience: Dr. Kosta and his whole office are THE BEST not only in Simi Valley, they are the best anywhere! Everyone is professional, friendly and gentle. We're so happy we found them!

Fantastic experience: Another great cleaning! I was very pleased with the service, the personnel was very pleasant. Everything went right on time, no waiting. Very happy for over 10 years

Fantastic experience: I appreciate the honesty Dr. Kosta and his staff possess. If there is an issue they will you know. If there isn’t they don’t make up a bunch of nonsense like so many other practices do.

Fantastic experience: Dr. Kosta is the best!! I just switched my plan so I could go back to having him as our dentist. I wish he was also my primary care Dr.! He is so nice, professional, funny and I actually enjoy going to the dentist now !! The office staff is always friendly and nice.

Fantastic experience: Chris was my hygienist today. He did a great job! Was gentle and explained and answered all my questions thoroughly

Fantastic experience: The staff were friendly, the person taken the x ray were patient and very positive. Dr was excellent in explaining what I have and what need to be done Overall, an excellent experience

Fantastic experience: The office staff was very helpful and kind. Dr. Kosta gave me the best cleaning I’ve had in years. He was thorough in his examination and extremely pleasant. He will continue to be my dentist.

Fantastic experience: Dr Kosta and his staff are all kind and courteous. Probably the most gentle dentist I have ever been to. My family has been seeing them for over 10 years. I hope he never retires!

Fantastic experience: Drove up from San Diego to see Dr Kosta as I used to go to him previously before moving. He always exceeds expectations! His whole office is full of the best, most kind and knowledgeable staff. 10000/10 recommend everytime!

Fantastic experience: Dr. Kosta is wonderful and so is his staff. (Nicole is my favorite. ❤️) They are friendly, caring, gentle, and HONEST! I am constantly referring friends and coworkers to this office and they all thank me. You cannot find a better dentist.

Fantastic experience: I cannot recommend Dr. Kosta and his team enough! From the moment I walked into his office, I was greeted with warmth and professionalism. The office is clean, modern, and well-organized, creating a comfortable atmosphere that instantly put me at ease.

Fantastic experience: Dr Kosta is the best. I am the biggest chicken and he handles it so well. He is kind, considerate, and very concerned about my comfort. He tells me whats happening as it is about to happen. I could and would never go anywhere else. The assistants are also very comforting.

Fantastic experience: Nice dentist locally here in Simi valley. Great personality, his staff is efficient and kind! Enjoyed my time with him! He’s gentle and easy to work with. Happy I found a good dentist locally! He didn’t push me about a tooth that had been pulled many moons ago. Great experience! Thanks Doc! See you soon!

Fantastic experience: Excellent staff!!!! Not to mention how they always accommodate to our needs and schedule. Love this dentist never hurts me and never pressures me for anything extra. Previous dentists always found something every 6 months & it was hundreds of dollars they wanted to charge and pressure pressure for additional services not covered by insurance. Thank you Dr Kosta and your staff and Happy Holidays

Fantastic experience: Absolutely love Dr Kosta and his entire staff. Nicole has been cleaning my teeth for years and I would cry if I had to go anywhere else. They treat us like family and never force unnecessary procedures. My seven year old even looks forward to his check ups.

Fantastic experience: I highly recommend Dr. Kosta’s Dental Office and his staff. For anyone that has had bad or traumatic experiences with past dentists, you will be happy to know that Dr.Kosta’s Dentistry will give you a new outlook on dentists all together. He is patient, he listens to you, and suggests the best treatment for you and you never have to wait. He has a wonderful team that work well with each other. And, best of all - when he gives the shots of Novocaine - There was NO pain! You can trust their work and professionalism . I thought I would never say this, but, I look forward to going to the dentist again!

Fantastic experience: Such an amazing Doctor. I’ve never really liked dentists since I was a kid but the moment you walk in you feel peace and once you’re in his chair he brings security and professionalism. Always does great dental work. Thank you Dr. Kosta!

Fantastic experience: The hygienist who took care of me was wonderful i hope to see her again in my next appointment. Thanks Dr Kosta!

Fantastic experience: Dr Kosta office is very clean! I have been coming here for over 2 years and Dr Kosta is the best dentist I have ever had. They always leave my teeth clean clean. I love it and the staff is so friendly!

Fantastic experience: Dr. Kosta’s office is amazing! Staff are very efficient, friendly, and caring. I had made a couple appointments after years of not going to the dentist, and I am so glad I picked this dentist office! I usually have pretty extreme anxiety going to the dentist, but they made it a much more relaxing experience. He always throughly explained what was happening, what needed to happen, and shows/explains the results of a procedure. He frequently checked to see if I was doing okay. I had to get some cavities cleaned up and filled for my last appointment and I was probably in and out within 25 minutes. Such a smooth experience! This is my go-to dentist from now on!

Fantastic experience: This is a great dental office. They are very kind, gentle and their hours are amazing. I was not a fan of the dentist until I came to Dr Kosta’s office. Now I look forward to my visits with the dentist. Thank you Dr Kosta and Team!

Fantastic experience: Been going to Dr. Kosta for about a year. Friendly, well run, front office. Had a wonderful dental hygienist today - previously I’ve had root canals and other work by Dr Kosta- he is one of the kindest dentists I have ever met. Dental problems are fully explained as well as pricing and insurance coverage. A great office overall - highly competent and professional but not pretentious.

Fantastic experience: It is such a pleasure to have Dr. Kosta’s as my dentist for more than 10 years! Along with an outstanding work he personally does, his hygienists and all office workers are extremely professional, kind and helpful. I believe Dr. Kosta truly loves his profession, he sincerely cares for his patients.

Fantastic experience: Dr. Kosta and staff are amazing. They make the whole dental cleaning experience a breeze (even if you have procrastinated on the recommended cleanings for a few years!).

Fantastic experience: First time at Dr Kosta’s office today for my wife and myself. Professional, friendly staff, hygienists did a wonderful job with cleanings, Dr Kosta was very personable, explained everything and gentle!

Fantastic experience: I love Dr. Kosta & his staff. Best dental experience I have ever had! Highly recommend!!!

Fantastic experience: Excellent Care!!! I broke a tooth at lunchtime, My wife called them to see how long it would be before I could see Dr.Kosta, they had me in his chair an hour and a half later!!! Wow great service, thank you Dr. Kosta

Fantastic experience: I have been going here a very long time. I love the service at Dr. Kosta office. They get you in right away, no long wait time. Dr. Kosta is amazing as well as his staff.

Fantastic experience: Not sure I can put into words how much I depend upon Dr. Kosta and his incredible staff. My family and I have been patients for 15 years. Professionals of the highest order is where they start. The entire practice is just like Dr. Kosta; empathetic, kind, easy to work with and all around great people. I’m so happy to be his patient and so will you.

Fantastic experience: Very happy with Dr Kosta and his friendly and professional staff. Dr Jonathan as well is very knowledgeable and professional. Thank you Dr Jonathan. Whatever you might need for your dental Health, you can trust Dr Kosta and his staff. Thank you Dr Kosta!

Fantastic experience: Doctor Kosta office is warm and welcoming. His team is kind, patient and gentle. Doctor Kosta is a kind, knowledgeable, nice doctor and he won’t overcharge like other places. I enjoy going to this office. Today I had a cleaning and the lady was sweet, patient and gentle. Didn’t felt rushed and it was a good experience. Thank you!

Fantastic experience: Everyone is just wonderful at this office. From the front receptionists, to the dental hygienist, to the doctor, they are calm, gentle and completely professional. If you are at all worried about going to a dentist, check out this practice.

Fantastic experience: Great care, nice and helpful staff, Dr. Kosta is terrific, always a great experience. Highly recommend if you're looking for a dentist.

Fantastic experience: From the front desk associate who remembered my name to the exam room with great views, this place is perfect. Dr. Kosta is quick and straight forward. I had a pleasant experience at the dentist! Who knew?

Fantastic experience: My first visit with Dr , Kosta was pleasant . Staff were friendly and he was very informative and took his time with me . He was also gentle and friendly. Coming back for my next cleaning . It’s been a long time since I’ve seen a great dentist . I found one finally.

Fantastic experience: Top tier service! Phenomenal crew who welcomes and treats you like family! Gentle and thorough cleaning, and Dr. Kosta is THE best dentist ever! Makes me look forward to go to the dentist!

Fantastic experience: Been with Dr Kosta for many years. He is a gentle man with awesome dental skills. Cannot recommend him highly enough! I do not trust anyone else with my teeth and I have had had a lot of dental work over the years. Experience, expertise and a gentle manner go a long way

Fantastic experience: Excellent care and outstanding staff! Dr. Kosta has been outstanding in tackling care of his clients. Very passionate and caring dental professional.

Fantastic experience: Want to start out by saying I’m not a very outspoken person. All I can say is I feel very welcome, comfortable and safe going to Dr. Costa’s office with my wife and two boys. I can’t recommend this practice enough. From business to dental care you are in good hands. Thank you for taking such good care of my family and I.

Positive experience: Clean waiting room, video screens playing kids friendly movies, friendly staff and gentle cleaning. I was able to get in and out in less than an hour. It is affordable for the average family.

Fantastic experience: Thank You Doctor Kosta! Dr. Kosta knows what he's doing, I think I have actually fallen asleep during s root canal. His staff and nurses are great! If you're looking for a good Dentist definitely this is the place!!

Fantastic experience: Had a filling break while visiting family. Dr. Kosta's office was able to get me in and get it replaced within a couple hours. The staff were all extremely kind and competent, and Dr. Kosta himself was great at explaining what he was doing and why.

Fantastic experience: There is no better place than Dr Kosta!!! He is sooo kind and gentle and always makes me feel safe. Like most people I had several bad experiences at the dentist and dr Kosta is the only dentist I’ll see now. I’ve been going to him for over 9 years and I don’t trust anyone else with me and my kiddos. I cannot recommend them enough. Also support staff is kind and well trained. A very smooth experience all the way around.

Fantastic experience: I came to Dr.Kosta for the first time today and are very satisfied. He is pointing out to you what is wrong and could be done but is not pushy at all. Today I got x-rays, an exam and teeth cleaning. Very happy :)

Positive experience: Love Dr. Kosta, love all the dental assistants. I was disappointed to be charged $50 for canceling an appointment the morning of a fees prior. I’d woken up sick and didn’t want risk making the staff sick. Aside from that, I’m very happy at this office.