By Matt Bruner, DDS, MS
It’s often the difficult Class III malocclusions that challenge orthodontists to think creatively and progressively. These cases are made even more difficult today with patient demands trending more and more toward nonextraction and nonsurgical treatment. The good news is that for some of these Class III cases, which historically would have taken more than ?24 months to treat, we are now able to utilize passive self-ligating appliances with light-force, low-friction orthodontics to achieve excellent results in 18 months.
In the following two cases, I will share recommended treatment protocols for skeletal Class III cases. While each patient requires a custom treatment plan, we’ve found the mechanics utilized below to be beneficial in successfully treating many Class III patients.
Damon Diva—Skeletal Class III Malocclusion
In 2012, Ormco™ Corp, Orange, Calif, launched a national consumer awareness program offering orthodontic treatment with the Damon™ System to a few select influencers in the family blogging space. The mommy bloggers were coined “Damon Divas” and started undergoing treatment. I was honored to work with Damon Diva Louise Bishop, who shared her adult treatment journey with readers of her popular “Mom Start” blog (momstart.com). When Damon Diva Louise came in for her exam, we quickly identified a skeletal Class III malocclusion, with an anterior crossbite and an anterior open bite (Figure 1).
Having worked with the Damon System for more than 10 years, I have grown confident in its ability to achieve excellent results in cases that were previously thought to be untreatable without extractions or jaw surgery. Even before our comprehensive orthodontic evaluation, a quick review of her records indicated it was going to be a difficult case to correct. I explained that my job was to educate her about our findings and motivate her to comply with our treatment recommendations.
In the same conversation, I stressed that great results come from patients with great cooperation. I further explained how the light forces and no friction forces with the Damon System allow for amazing results, especially when paired with light early elastic wear. It should be noted that elastic wear works most efficaciously when coupled with disarticulation that temporarily opens the bite. This frees teeth to move without intercuspal interferences, and effectively renders the masseter muscles ineffective in their effort to paralyze tooth movement.
We placed her braces on all 28 teeth, and Louise was set up to wear early, light, short Class III elastics from day one. Her anterior open bite was being exacerbated by her low anterior tongue position. To correct this, we bonded tongue tamers (habit reminders) behind her lower incisors to help keep her tongue back. Perhaps most significantly, we wanted to control and counteract the protrusive forces as crowding unraveled, so we chose a low-torque upper and lower incisor prescription.
To fully take advantage of the low-torque incisor brackets, we modified our archwire sequence to engage the torque control earlier in treatment. We used .018″ x .018″, .020″ x .020″, and 019″ x .025″ Copper NiTi archwires as our second, third, and fourth wires instead of .018″, .014″ x .025″, and .018″ x .025″.
As you can see from her progress photos (Figure 2), her crowding began to unravel and teeth began to align quickly. Her occlusion, though, was slightly more open. She continued to wear Class III elastics, and we added upper molar bite pads with squeezing exercises for her masseters and temporalis muscles. Putting vertical forces on the molar pads intruded her molars and closed her open bite.
We achieved great results with regard to our goals of improved function, stability, and esthetics (Figure 3). Ideally, I would have tinkered for a few more appointments for the absolute perfect finish, but she was ready to get her braces off. In this case, we took the patient from a Class III to Class I, improved her alignment, prevented protrusion, corrected the crossbite, closed the open bite, and improved her smile display—all in 14 months total treatment time.
25-Year-Old Female—Skeletal Class III Case
This second Class III skeletal case demonstrates another treatment approach for a patient who was requesting a perfect smile without extractions or surgery (Figure 4). The patient was a 25-year-old female with the common request of, “I want to fix my teeth.” There were a unique and robust set of challenges found at the initial diagnosis: Class III skeletal and dental relationships, apertognathia, anterior crossbite, moderate upper to lower arch length discrepancies, and a large tongue with anterior tongue posture. Additionally, she presented with crowded and slightly proclined upper and lower incisors, and a reverse smile arc with minimal incisal display, even in a fully animated smile.
From the start, the patient expressed a desire to complete treatment without orthognathic surgery and without any teeth being extracted. Although challenging, our treatment plan and goal was to provide her with comprehensive nonextraction orthodontic treatment to alleviate crowding, upright the incisors, reduce her protrusion, establish a functional overbite and overjet, increase incisal display, and improve her smile arc.
Traditional fixed orthodontic appliances alleviate crowding but often end up with incisor protrusion. The Damon System’s passive self-ligation allowed us to achieve our goals of arch development without protrusion. Early light short elastics were utilized to help correct the Class III bite, improving her overbite and overjet. To control the protrusion early and throughout treatment, we used early, large rectangular archwires and low-torque incisor prescriptions. This allowed for archwire bracket slot engagement earlier in treatment, which resulted in excellent control of incisor protrusion.
Beginning at the initial bonding, we placed tongue reminders behind the lower incisors to aid in establishing a more posterior tongue position. With the tongue less of an issue, we added posterior bite pads and prescribed squeezing exercises for the patient to complete morning and night. All of these tactics worked together to add vertical control and helped us achieve anterior open bite closure.
After approximately 17 months of treatment, the patient was ecstatic about her results (Figure 5). The passive self-ligation treatment approach, paired with early light elastics and tongue tamers, resulted in a Class I occlusion with improved smile esthetics, and more tooth display at rest and in animation. The light gentle forces applied with good torque control allowed all of this to be achieved while maintaining or improving the incisor position.
In all cases, and especially in difficult Class III cases, patient education is of paramount importance to obtain a high degree of patient compliance with intraoral elastic wear, oral hygiene, and bite squeezing exercises—which all work together to correct multiple issues simultaneously. We’ve found passive self-ligating bracket technology key in achieving results that were previously not thought possible. OP
Matt Bruner, DDS, MS, is a board-certified orthodontist who trained at the University of Louisville and honed his skills serving as the chief of orthodontics at Tripler Army Medical Center in Hawaii. After serving 9 years in the US Army Dental Corps, he returned to his hometown of Redmond, Wash, buying the practice where he had braces as a teenager. He has another practice in Duvall, Wash. Bruner teaches at the University of the Pacific.