Orthodontic Appliances


Headgear | Hyrax | Lower Lingual Arch | Nance Appliance | Sagittal Appliance | Schwartz Appliance | Three-Way Appliance | Thumb/Finger Appliance | Tongue Thrusting Appliance | Twin Block

At the orthodontic practice of Dr. Radha Krishnan, we proudly provide exceptional orthodontic care to patients of all ages using a wide assortment of orthodontic treatment methods to ensure we can meet each patient's individual needs and desires. As a leading Calvert & St. Mary's County orthodontist, Dr. Krishnan utilizes all the latest technological advances in orthodontics to ensure each patient receives the best possible treatment and optimal outcome which is a healthy, straight and beautiful smile!

Dr. Krishnan uses many different orthodontic appliances when providing his patients with the treatment they need. He may recommend one or more of the following appliances to help you get that great new smile. Which type of orthodontic appliances you will wear will depend upon the orthodontic problems being addressed. Each case is treated uniquely, based on each patient's individual needs. We are always available to answer any questions you may have about your treatment or the appliances we use.

Below are the various appliances Dr. Krishnan may recommend for your orthodontic treatment.


headgear.jpgHeadgear is often used to correct an excessive overbite. This type of appliances puts pressure against the upper teeth and jaw to hold the teeth in position or to help move them into more optimal positions. How long headgear must be worn depends upon the severity of the problem being addressed. In order for treatment with headgear to succeed, it is imperative that the headgear be worn as directed. If the appliance is not worn for the specific number of hours we recommend, the lost time wearing it can be made up the following day. Headgear should never be worn while playing sports and it needs to be removed when eating and brushing and flossing.


hyrax.jpgThe Hyrax appliance is either removable or bonded. This appliance expands the upper jaw to avoid crowding or cross bites from occurring. Bonded Hyrax appliances are commonly used by younger patients who still have their primary molars, while the removable Hyrax is used by patients whose permanent molars have come in. The Hyrax appliance is designed to widen the upper jaw one-fourth millimeter per turn and it takes approximately six weeks to attain the desired width. After this period, we will use plastic to stabilize the appliance for up to three months at which time a retainer is used to hold the jaws in the new position.

Lower Lingual Arch

lingualarch.jpgA Lower Lingual Arch is used to keep the molars from drifting forward and to prevent them from blocking the space where permanent teeth will eventually erupt. This appliance is commonly used when a patient has prematurely lost primary teeth or when a young child's lower teeth are somewhat crowded.

Because some soreness can be experienced when first wearing this appliance, it may be uncomfortable to chew food. Therefore, we recommend eating only soft foods for the first few days. Advil or Tylenol can be taken to relieve any discomfort you feel. It is important to steer clear of sticky and hard foods and to watch how many snacks you eat which are high in sugar.

It is important to do a good job of brushing and flossing when wearing a Lower Lingual Arch appliance. Be sure to clean around the bands that are connected to the molars and the wire on the tongue side to help you avoid tooth decay and gum problems. How long this appliance must be worn is determined on a case-by-case basis. We will monitor the eruption of new teeth and make any necessary adjustments. Generally, the Lower Lingual Arch is removed once all the permanent teeth have come in.

Nance Appliance

nance.jpgThe Nance Appliance prevents the upper molars from rotating or moving forward after wearing a headgear or any appliance used to move the molars back. Some patients wear this appliance while waiting for their bicuspids to come in. This is a fixed appliance made of two bands that are cemented onto the first molars with a wire spanning the roof of the mouth. A piece of acrylic that fits against the roof of the mouth sits in the center of the wire.

Patients wearing this appliance can brush their teeth as they normally do while being sure to brush well around the bands. Sticky and chewy foods should be avoided as they can stick to the appliance.

Sagittal Appliance

sagittal.jpgUsed to expand the upper jaw, the Sagittal appliance is an appliance made of acrylic and metal and is designed to fit comfortably in the roof of the mouth. There is a small screw built into this appliance, which is turned slightly over a period of time to activate the expansion of the jaw. It is important to follow the directions you're given about how and when this screw should be turned.

Schwartz Appliance

schwartz.jpgPrimarily used on the maxillary or upper arch to expand the arch and create needed additional space for the permanent teeth, the Schwartz Appliance is a removable expansion appliance. While the exact time spent wearing the Schwartz Appliance varies case by case, most patients experience a treatment time of about nine months to one year.

Three-Way Appliance

cropped-3-way.jpgThe Three-Way Appliance is used to expand the upper arch in three directions: The front forward (length-wise) and the back transversely (both directions width-wise) in one combined appliance. This appliance expands the arch to eliminate crowding and to establish an optimal relationship to the lower jaw by using a special 3-way expansion screw or three individual screws.

Thumb/Finger Appliance

thumbfinger.jpgWhile most children cease sucking their thumbs between the ages of 2 and 4, some children continue this habit. When a child sucks their thumb after the primary teeth have come in, it can lead to improper growth of the mouth and misaligned teeth. A Fixed Palatal Crib appliance is an appliance that's place behind the child's upper teeth to stop the thumb sucking habit. This appliance consists of semicircular stainless steel wires that are attached to molars with steel bands. Because the wires are behind the upper front teeth, they are virtually undetectable. This appliance is very effective at quickly stopping a thumb sucking habit.

Tongue Thrusting Appliance

thumbfinger.jpgTongue thrusting takes place when the patient presses his or her tongue against the front teeth when swallowing, speaking or resting the tongue. Ongoing tongue thrusting can cause the teeth to become misaligned wherein they will need correction. A tongue thrusting appliance is similar to a mouth guard and it is usually worn at night. Other times, we prescribe a more permanent appliance that can only be adjusted by our office.

Twin Block

photos-for-appliance-page-.jpgThe Twin Block functional appliance is used to correct jaw positioning so the bite is properly aligned. The Twin Block consists of an upper and lower plate, which work together to pull the lower jaw forward. This appliance can be used by patients of all ages but it is most often during Phase 1 orthodontic treatment in children who have underdeveloped jaws.

The Twin Block appliance must be worn as directed and only removed when brushing and flossing and when playing sports. We will provide instructions on how to activate the screw. It is not uncommon to experience some temporary discomfort and difficulty speaking the first few days of wear. It is imperative to follow the instructions you are given so you can achieve the optimal results within the least amount of time.

Contact Your Calvert & St. Mary's County Orthodontist

Dr. Krishnan and his team are always happy to speak with you! If you have any questions about the appliances we use, please don't hesitate to contact us. Our orthodontic office is centrally located in Prince Frederick, Maryland for the convenience of our patients. We offer excellent orthodontic care to patients of all ages living in the four Southern Maryland Counties of Calvert, St. Mary's, Charles and Anne Arundel.