A misaligned bite, or malocclusion, is a common condition where the upper and lower teeth do not meet correctly when the jaws are closed. This improper alignment stems from issues with the teeth, the relationship between the upper and lower jaws, or both. Malocclusion affects the appearance of a smile, interferes with functions like chewing and speaking, and may contribute to uneven tooth wear and jaw discomfort. Correcting a misaligned bite significantly improves oral health, function, and the longevity of the natural teeth.
Understanding Malocclusion Types
Malocclusion is classified based on the relationship between the upper and lower jaws, particularly the position of the first molars, using Angle’s classification system. This system defines three main classes. Class I malocclusion involves a normal jaw relationship, but the teeth may still exhibit crowding, rotation, or spacing issues. Class II malocclusion occurs when the upper jaw or teeth are positioned significantly forward relative to the lower jaw, often resulting in an overbite or overjet where the upper front teeth protrude horizontally past the lower teeth.
Class III malocclusion is the opposite, characterized by the lower jaw or teeth extending forward past the upper teeth, known as an underbite. Malocclusions are further distinguished by their origin: dental or skeletal. A dental malocclusion involves poor positioning of the teeth within correctly aligned jaws, while a skeletal malocclusion results from a size or growth discrepancy between the upper jaw (maxilla) and the lower jaw (mandible).
Other specific bite issues include a crossbite, where the upper teeth tuck inside the lower teeth on one or both sides. An open bite occurs when the upper and lower front teeth fail to overlap or touch when the back teeth are closed, creating a gap. Identifying the specific type and origin of the misalignment determines the appropriate treatment pathway.
Standard Orthodontic Treatment Methods
For most malocclusions without severe skeletal discrepancies, standard orthodontic appliances are the primary method of correction. These devices apply light, continuous forces to the teeth, gradually moving them into alignment.
Fixed Appliances (Braces)
Traditional fixed appliances, including metal and ceramic braces, are highly effective for complex tooth movements, such as severe rotations and deep bite corrections. Metal brackets are bonded to the teeth and connected by an archwire, which is periodically adjusted to guide movement. Treatment typically lasts between 18 and 36 months.
Ceramic braces function identically but use tooth-colored or clear brackets for a more discreet appearance. While effective, ceramic brackets may create slightly more friction, potentially extending treatment time compared to metal braces. Both types use consistent, controlled force for predictable alignment.
Clear Aligners
Clear aligner therapy uses a series of custom-made, transparent plastic trays worn sequentially. Each tray is engineered for small, incremental movements before the patient switches to the next set, typically every one to two weeks. This method is suitable for mild to moderate crowding, spacing, and minor bite corrections, requiring consistent wear for 20 to 22 hours per day. Clear aligners offer an aesthetic and removable option but may be less efficient than fixed braces for highly complex movements.
Auxiliary Appliances
Other standard appliances are often used before or with braces, particularly in growing patients. A palatal expander is a fixed device cemented to the upper back teeth to widen a constricted upper jaw. The expander gently separates the two halves of the palate, a process most successful before the midpalatal suture fuses in adolescence. This expansion corrects posterior crossbites and creates necessary space, potentially reducing the need for future tooth extractions.
Surgical and Advanced Interventions
When malocclusion results from a significant skeletal discrepancy—where the jawbones are mismatched in size or position—advanced interventions are necessary.
Orthognathic Surgery
Orthognathic surgery, or corrective jaw surgery, repositions the upper jaw, lower jaw, or both, when misalignment is too severe for tooth movement alone. This procedure is typically reserved for adults whose facial growth is complete. It addresses severe Class II or Class III discrepancies, facial asymmetry, or functional issues like sleep apnea.
The treatment is multi-phase, requiring pre-surgical orthodontics to align the teeth within their respective jaws. During surgery, an oral and maxillofacial surgeon makes precise cuts (osteotomies) to move the jawbone into the correct position, stabilizing the new alignment with titanium plates and screws. A final phase of orthodontics fine-tunes the bite afterward.
Specialized Appliances
Specialized appliances provide force vectors that standard braces cannot achieve. Headgear is an extraoral appliance used primarily in growing patients to guide jaw growth and correct significant Class II (overbite) or Class III (underbite) issues. For instance, high-pull headgear restricts the growth of the upper jaw, while a reverse-pull headgear encourages the forward growth of a deficient upper jaw.
Temporary Anchorage Devices (TADs) are miniature titanium screws temporarily placed into the jawbone. TADs act as fixed, non-moving anchor points, providing absolute stability. This allows the orthodontist to move specific teeth with greater precision and in directions previously difficult without surgery. Their use can shorten treatment time, eliminate the need for headgear in some cases, and help close open bites by intruding the back teeth.
Ensuring Long-Term Bite Retention
The successful correction of a misaligned bite requires a crucial phase known as retention to maintain the achieved results. Teeth have a natural tendency to drift back toward their original positions, known as relapse, due to the memory of the periodontal ligaments and pressures from the tongue and lips. Retainers are custom-made devices that stabilize the teeth while the surrounding bone and soft tissues adapt to the new alignment.
There are two main types of retainers: removable and fixed. Removable options include the classic Hawley retainer (metal wire and acrylic plate) or clear plastic retainers, similar to aligners. Fixed, or bonded, retainers consist of a thin wire cemented to the back surface of the front teeth, providing continuous support. Orthodontists typically recommend full-time wear of a removable retainer initially, transitioning to indefinite nighttime use to ensure long-term stability.