Orthodontic treatment, commonly known as braces, is a structured biological process designed to correct misaligned teeth and improper bites (malocclusions). While the standard course of care involves three overarching stages—planning, active movement, and post-treatment maintenance—the term “phases” often refers to a specific, two-stage clinical approach used primarily for children. The general progression of care for most patients follows these three distinct stages, beginning before any appliance is placed and continuing long after it is removed.
Initial Assessment and Planning
The treatment journey begins with a comprehensive initial consultation focused on diagnosis and preparation. The orthodontist evaluates the patient’s oral health, including tooth alignment, gum condition, and the relationship between the upper and lower jaws. This foundational step determines the complexity and estimated duration of the subsequent treatment.
Diagnostic records are collected, typically involving digital X-rays, 3D scans, and impressions to create study models. Panoramic and cephalometric X-rays provide detailed views of the dental structure and jaw relationships. The orthodontist uses these records to identify the malocclusion and formulate a precise, personalized treatment plan.
This initial stage also includes necessary pre-treatment procedures, such as placing orthodontic spacers or coordinating tooth extractions. The planning stage is complete once the specific appliance—traditional braces or clear aligners—is selected and the timeline is finalized.
The Active Treatment Phase
This is the lengthiest and most visible stage, where appliances move the teeth into their desired positions. The mechanism involves applying continuous, gentle force using brackets and wires. This pressure stimulates a biological response in the bone, causing it to resorb on one side and deposit new bone on the other, allowing the tooth to gradually shift.
Patients visit the orthodontist regularly, typically every four to eight weeks, for adjustment appointments. During these visits, archwires are tightened, replaced, or bent to maintain the necessary pressure. The archwire progresses from flexible, lighter wires for initial alignment to stiffer, thicker wires for root alignment and bite correction.
Elastics (rubber bands) play a significant role in the later part of the active phase, correcting the bite relationship between the upper and lower jaws. They are worn between the arches to ensure the teeth interlock correctly, achieving proper occlusion. The duration of this phase generally ranges from 18 to 30 months, depending on the severity of the alignment problem and patient compliance.
The Retention Phase
Once active appliances are removed, the patient transitions into the retention phase. This stage is essential because the bone and gum tissues surrounding the newly moved teeth require time to stabilize around the new root positions. Without retention, the teeth have a strong tendency toward relapse, shifting back toward their original misalignment.
Retention involves the mandatory use of a custom-made retainer designed to hold the teeth in their corrected position. Retainers are divided into two main categories: fixed and removable. Fixed retainers are thin wires permanently bonded to the backside of the front teeth, providing constant stability.
Removable retainers include the Hawley retainer (metal wires and acrylic) and the Essix retainer (a clear, vacuum-formed plastic shell). Patients wear removable retainers full-time initially, transitioning to nightly wear indefinitely. Orthodontic consensus recommends long-term or lifetime retention to counteract the natural tendency for teeth to shift over time.
The Concept of Two-Phase Treatment
The term “two-phase treatment” is reserved for a minority of patients, usually children aged six to ten, who have significant skeletal or dental issues benefiting from early intervention. This approach uses two distinct active treatment periods separated by a resting period, unlike the standard three-stage process.
Phase I, or interceptive treatment, focuses on correcting jaw discrepancies or severe crowding while the child is still growing. Appliances like palatal expanders are used to guide jaw growth, correct crossbites, or create space for permanent teeth. This early phase typically lasts 9 to 12 months and improves the foundational environment of the mouth.
After Phase I, a resting period follows while the remaining permanent teeth erupt and the orthodontist monitors growth. Phase II, or comprehensive treatment, begins later in adolescence once most permanent teeth are present. This final phase involves placing full braces or aligners to achieve precise alignment and fine-tune the bite relationship, leading directly into retention.