A common misconception is that if you have an “overbite” there is something wrong with your teeth or bite. That’s definitely not the case! Like most things in life, moderation is key. The right amount of overbite is actually necessary for a healthy bite.
What is Overbite?
Overbite is the orthodontic term used to describe the amount of vertical overlap between your upper and lower teeth when you bite down. Too little overlap and the bite is described as shallow, edge-to-edge or open. Too much overlap and the overbite is termed deep or excessive.
About 2-3 mm of overlap is just the right amount of overbite for teeth to function properly when chewing, directing biting forces in the proper direction and the right amount. When your orthodontist measures overbite, it can be noted as either a measurement in mm or a measurement in percentage of overlap.
What is a Deep Bite?
When bites are “deep” it’s often because the lower anterior teeth (these are the six front teeth canine to canine) are too far behind the upper anterior teeth. These front teeth keep “growing” past each other because teeth have a tendency to erupt out of bone until they hit an opposing force. When the front teeth “occlude” too close to the gums of the opposing arch, this causes chipping and wear of the tooth enamel over time. Enamel doesn’t grow back once it’s gone, and over decades of chewing and
bruxing (grinding), the teeth can shorten significantly.
Keep in mind that an overbite can be caused by an improper upper and lower tooth relationship, an improper upper and lower jaw relationship, or a combination of both.
Deep overbites often have a pronounced “curve” to their lower biting plane called the “Curve of Spee.” This was named after Ferdinand Graf von Spee, a German scientist who lived from 1855–1937 and he was the first person to describe the anatomic relations of human teeth in this plane of space.
Treatment for Excessive Overbite
People often ask how the overbite will be corrected. Most often, excessive overbite is resolved by leveling this Curve of Spee: extruding the lower posterior teeth and intruding and proclining the lower anterior teeth. Extrusion means moving teeth away from the bony base, intrusion is moving teeth towards or into the bony base. Sometimes the upper front teeth must be intruded to correct a deep bite as well. It’s important not to intrude the upper teeth too much when correcting a deep bite because that can cause the lip to cover more of the upper front teeth in a smile, and that is not a desirable outcome esthetically.
Case Study
In this case, Samantha had her upper incisors (front teeth) covering nearly 100% of her lower incisors (front teeth) when she bit down.
We corrected her deep overbite and crowding with aligner therapy, several attachments, and elastics in approximately 18 months. Her upper teeth were initially excessively retroclined, or tipped back towards her palate, and she had moderate crowding in her lower arch. In order to straighten her lower teeth, her upper teeth had to be proclined, or tipped forward towards her lips. This gave her lower teeth room to procline forward as the crowding, or overlap between the teeth, resolved. It also improved her smiling profile and lip support or fullness in profile.
She also had retained primary second molars and missing permanent second premolars. Whenever possible, we try to keep these primary teeth to avoid or prolong the need for restorations. Despite these missing teeth preventing us from achieving a textbook Class I posterior bite, her final bite is now much healthier and will cause less trauma to her enamel over a lifetime.
Visit High Line Orthodontics
Deep overbites don’t get better on their own, and it’s not something that a child will outgrow. In fact, deep bites get worse over the years as the teeth wear away. Dr. Pompei will create a treatment plan for your unique orthodontic situation that will result in a healthier bite and a beautiful smile! Request a consultation today.
