Orthodontics, a specialized field of dentistry, focuses on diagnosing, preventing, and treating dental and facial irregularities. One common classification system used by orthodontists to describe the relationship between the upper and lower teeth and jaws is the Angle classification system. This system categorizes malocclusions (misalignments of the teeth) into three main classes: Class I, Class II, and Class III. Among these, Class II malocclusions are particularly significant and often require specialized treatment approaches.
Understanding Malocclusion
Before discussing Class II malocclusion in detail, it is essential to understand the concept of malocclusion itself.
Malocclusion refers to the misalignment of teeth when the jaws are closed. It can result in functional problems, such as difficulty in chewing and speaking, as well as aesthetic concerns. The Angle classification system, developed by Dr. Edward Angle in the late 19th century, remains a widely used framework for categorizing different types of malocclusions.
see also: Is Orthodontic Treatment Just Wearing Braces?
Angle Classification System
The Angle classification system is based on the position of the first molars and the relationship between the upper and lower dental arches. It divides malocclusions into three primary classes:
Class I Malocclusion: This is the most common type, where the bite is normal, but there may be crowding, spacing, or other dental irregularities.
Class II Malocclusion: This type involves a retrusive lower jaw (mandible) or a protrusive upper jaw (maxilla), resulting in an overbite.
Class III Malocclusion: This type is characterized by a protrusive lower jaw or retrusive upper jaw, resulting in an underbite.
What Does Class II Mean in Orthodontics?
Class II malocclusion, also known as distoclusion, occurs when the upper jaw and teeth significantly overlap the lower jaw and teeth. This misalignment can lead to various functional and aesthetic issues, making it a critical area of focus in orthodontic treatment.
Types of Class II Malocclusion
Class II malocclusion is further divided into two main subtypes:
Class II Division 1: This type is characterized by a significant overjet, where the upper front teeth are excessively protruded. Patients with Class II Division 1 often have a convex facial profile and a pronounced overbite.
Class II Division 2: In this type, the upper front teeth are tilted backward (retroclined), causing the lower front teeth to overlap the upper front teeth. Class II Division 2 is associated with a deep bite and a more retrusive upper jaw.
Causes of Class II Malocclusion
Class II malocclusion can result from a combination of genetic, developmental, and environmental factors. Some common causes include:
Genetics: A family history of Class II malocclusion can increase the likelihood of developing this condition. Genetic factors influence the size and shape of the jaws and teeth, contributing to the misalignment.
Jaw Growth Discrepancies: Discrepancies in the growth of the upper and lower jaws can lead to Class II malocclusion. For example, an overdeveloped upper jaw or an underdeveloped lower jaw can result in an overbite.
Thumb Sucking: Prolonged thumb sucking during childhood can affect the development of the jaws and teeth, potentially leading to Class II malocclusion.
Pacifier Use: Extended use of pacifiers beyond infancy can also contribute to the development of Class II malocclusion.
Mouth Breathing: Chronic mouth breathing, often due to nasal obstructions or allergies, can influence the growth and alignment of the jaws, resulting in Class II malocclusion.
Diagnosing Class II Malocclusion
Accurate diagnosis of Class II malocclusion is essential for developing an effective treatment plan. Orthodontists use various diagnostic tools and techniques to assess the severity and type of malocclusion:
Clinical Examination: The orthodontist performs a thorough clinical examination, evaluating the patient’s dental and facial structures. This includes assessing the bite, alignment of the teeth, and facial profile.
Dental Impressions: Dental impressions are taken to create models of the patient’s teeth. These models help in analyzing the occlusion and planning the treatment.
X-Rays: X-rays, such as panoramic and cephalometric radiographs, provide detailed images of the teeth and jaw structures.
Cephalometric analysis is particularly useful in assessing the skeletal relationships and growth patterns.
Photographs: Intraoral and extraoral photographs are taken to document the patient’s dental and facial features. These photographs aid in treatment planning and monitoring progress.
Treatment Options for Class II Malocclusion
Treatment of Class II malocclusion aims to correct the misalignment, improve dental function, and enhance facial aesthetics. The choice of treatment depends on factors such as the patient’s age, severity of the malocclusion, and specific needs. Common treatment options include:
1. Orthodontic Appliances
Orthodontic appliances play a crucial role in correcting Class II malocclusion. These appliances can be fixed or removable, and they work by applying gentle pressure to move the teeth and jaws into their proper positions. Some commonly used orthodontic appliances include:
Braces: Traditional braces consist of brackets, wires, and bands that are attached to the teeth. Braces gradually shift the teeth and jaws to achieve the desired alignment.
Clear Aligners: Clear aligners, such as Invisalign, are removable and virtually invisible. They are custom-made to fit the patient’s teeth and are changed periodically to guide the teeth into their correct positions.
Headgear: Headgear is an external orthodontic appliance that helps guide the growth of the jaws. It is typically used in growing patients to correct Class II malocclusion.
Herbst Appliance: The Herbst appliance is a fixed appliance that helps correct the position of the lower jaw. It is commonly used in growing patients to address Class II malocclusion.
2. Functional Appliances
Functional appliances are designed to influence the growth and development of the jaws, particularly in growing children.
These appliances can help correct Class II malocclusion by encouraging the forward growth of the lower jaw and modifying the position of the upper jaw. Examples of functional appliances include:
Twin Block Appliance: The twin block appliance consists of upper and lower bite blocks that encourage the lower jaw to move forward. It is effective in correcting Class II malocclusion and improving the patient’s profile.
Bionator: The bionator is a removable appliance that promotes forward growth of the lower jaw and improves the alignment of the teeth.
3. Orthognathic Surgery
In severe cases of Class II malocclusion, where orthodontic appliances alone are insufficient, orthognathic surgery may be necessary.
Orthognathic surgery involves repositioning the jaws to achieve proper alignment and function. This surgical procedure is typically performed in conjunction with orthodontic treatment to ensure optimal results.
4. Tooth Extraction
In some cases, tooth extraction may be required to create space for proper alignment of the teeth and jaws. This approach is more common in patients with severe crowding or protrusion. The orthodontist carefully evaluates the need for extractions based on the individual’s specific condition.
5. Retention Phase
After the active phase of orthodontic treatment, a retention phase is necessary to maintain the results. Retainers are used to prevent the teeth from shifting back to their original positions. Retainers can be fixed or removable and are worn as prescribed by the orthodontist.
Conclusion
Class II malocclusion is a common dental condition characterized by the misalignment of the upper and lower jaws.
Understanding the causes, types, and treatment options for Class II malocclusion is essential for achieving optimal dental health and aesthetics. Orthodontic treatment, including braces, functional appliances, and orthognathic surgery, plays a crucial role in correcting this condition and improving the patient’s overall quality of life. By addressing Class II malocclusion, patients can enjoy improved dental function, enhanced aesthetics, and long-term stability of their orthodontic results.