Fixed orthodontic appliances are devices used in orthodontics to address dental alignment and bite concerns. They gently reposition teeth over time, improving both the function and appearance of a person’s smile. Designed to remain on teeth throughout treatment, these appliances provide consistent force to correct issues like crowded teeth, gaps, overbites, and underbites.
Understanding Fixed Orthodontic Appliances
Fixed orthodontic appliances encompass several types, each with distinct characteristics regarding materials, visibility, and placement.
Traditional metal braces are a common form, made from high-grade stainless steel. They consist of small metal brackets bonded to the front surface of each tooth, connected by a thin archwire. Metal braces are highly effective and a frequently chosen option.
Ceramic braces offer a less noticeable alternative. They use translucent or tooth-colored ceramic brackets that blend with natural tooth shade. Ceramic brackets can be less durable than metal ones, and their elastic ties may stain between appointments. This option is favored by adults.
Lingual braces are designed for maximum discretion. Unlike other types, lingual brackets are custom-made and bonded to the back (tongue-side) surfaces of the teeth. This placement makes them virtually invisible from the front, but they can be more challenging to clean and may initially affect speech. Lingual braces require specialized training and are not suitable for every case.
How Fixed Appliances Move Teeth
The movement of teeth with fixed orthodontic appliances relies on a precise biological process driven by continuous, gentle forces. Teeth are not rigidly fixed within the jawbone; instead, they are suspended by a flexible network of fibers known as the periodontal ligament. This ligament connects the tooth’s root to the surrounding bone, allowing for slight, controlled movement in response to sustained pressure.
Fixed appliances, composed of brackets, archwires, and sometimes elastics, work together to apply this pressure. Brackets are small components bonded directly to the tooth surface, serving as attachment points. A thin archwire is then threaded through these brackets, acting as the primary force-generating element. As the archwire seeks to return to its original shape, it exerts a pushing or pulling force on the teeth through the brackets, guiding them along a predetermined path.
This applied pressure initiates a process called bone remodeling in the jawbone surrounding the teeth. On the side of the tooth where pressure is applied, the periodontal ligament is compressed, leading to a reduction in blood flow. This compression stimulates specialized cells called osteoclasts to resorb, or break down, the adjacent bone. Simultaneously, on the opposite side of the tooth, the periodontal ligament stretches, prompting osteoblasts to deposit new bone. This coordinated breakdown and buildup of bone allows the tooth to gradually move through the jawbone, typically at a rate of approximately 1 millimeter per month.
The Patient Experience
The journey with fixed orthodontic appliances begins with an initial consultation. The orthodontist evaluates the patient’s bite and alignment, outlines treatment objectives, and discusses the proposed plan, including overall health. Appliance placement involves bonding brackets to each tooth and threading archwires. In some cases, metal bands may be cemented around back molars for additional anchorage.
Throughout treatment, patients attend regular adjustment appointments, typically every four to eight weeks. During these visits, the orthodontist adjusts or replaces archwires to continue applying precise forces to the teeth. Elastics, if prescribed, may also be changed or added to facilitate specific tooth movements or correct bite relationships.
Patients may experience pressure or a dull ache in the teeth and jaw after initial placement and adjustments, which usually subsides within a few days to a week. Brackets and wires may also cause minor irritation to the inner cheeks, lips, or tongue. Orthodontic wax can be applied to cover rough spots and alleviate discomfort.
Living with fixed appliances requires adjustments to dietary habits. Patients should avoid hard, sticky, or chewy foods that could damage brackets or wires, such as nuts, popcorn, hard candies, or chewing gum. Foods like whole apples or corn on the cob should be cut into smaller pieces. Softer foods are often recommended, especially during the initial days after placement or adjustments.
Maintaining meticulous oral hygiene is important with fixed appliances, as food particles can easily become trapped around brackets and wires. Thorough brushing after every meal is necessary, often with specialized orthodontic toothbrushes or interdental brushes. Using floss threaders or water flossers can help clean between teeth and under the archwire. Neglecting oral hygiene can lead to plaque buildup, tooth decalcification, and gum inflammation.