A Simple Lingual Alignment Technique for Mandibular Incisor Crowding

by Bruno L. Vendittelli, DDS, D. Ortho, FRCD(C) and Sarah McKinlay, RDH

Where wrinkles, frown lines and loss of skin tone are evidence of facial aging, aging of the dentition is characterized by generalized recession, loss of alveolar bone height and loss of tooth alignment.1,2 Approximately two thirds of untreated adolescents with normal occlusions will develop incisor irregularity by early adulthood as a result of changes in the mandibular arch.2-4 Mandibular incisor crowding typically occurs into the fifth decade and potentially throughout life.5,6 Mandibular arch changes in an orthodontically treated dentition are dynamic and constantly changing; mandibular incisor crowding may reappear over time particularly in the absence of lifelong retention.7

There is a growing trend in anti-aging techniques. The increased prevalence of elective cosmetic techniques reflects the public’s desire for an appearance of youth and a growing acceptance of the procedures associated with this trend. Since 1997, the prevalence of surgical procedures and non- surgical procedures has increased 114 and 754 percent respectively.8

Dental treatment is arguably the most accepted method of basic cosmetic enhancement. Orthodontic treatment has been a long-standing solution to a compromised dentition. Once reserved mainly for children, more adults continue to seek treatment as they increase their presence in specialty practice.

Various options exist to address mandibular incisor crowding including metal or ceramic fixed labial appliances, spring retainers and other traditional removable appliances, lingual fixed appliances and clear removable aligners such as InvisalignTM. All appliances will yield an acceptable clinical result in spite of the deficiencies inherent to their respective designs. Fixed labial appliances are esthetically unacceptable to many adult patients. Similarly, traditional removable appliances are considered too large and too bulky for everyday use and may result in unpredictable tooth movement. InvisalignTM provides improved esthetics and predictability in comparison to traditional removable appliances, yet requires strict patient compliance for maximal results. InvisalignTM also involves a complex laboratory component generating higher costs to the patient in comparison to alternate treatment modalities.

This article presents a fixed lingual treatment protocol for mandibular incisor crowding that is simple, esthetic and produces minimal side effects with respect to the overall occlusion.

Case Selection
The ideal candidate for mandibular anterior lingual appliances has the following characteristics:
1. Crowding of the mandibular incisors
2. An ideal occlusion or a functional posterior malocclusion with no potential for long-term complication if left untreated.
3. Overall periodontal stability.
4. A desire for an esthetic treatment system.

Appliance System
The SPEED miniature self-ligating bracket used in conjunction with light archwires is the basis for efficacious incisor alignment. 0.018″ slot mandibular labial incisor brackets are bonded indirectly to the lingual surfaces of the six mandibular anterior teeth using a silicone-based transfer tray (Figs. 1a-c).

Initial alignment is achieved through the light force delivery of an 0.016″ or an 0.018″ SupercableTM.9 0.016″ nickel titanium and 0.016″ or 0.018″ titanium molybdenum alloy (TMA) archwires provide for final alignment and detailing respectively. Judicious interproximal reduction of the mandibular incisors creates the space for alignment in the majority of cases. A single mandibular incisor may be extracted in cases with moderate to severe crowding. Treatment duration is six to twelve months, depending on the severity of crowding pre-treatment. At the completion of treatment long-term retention is provided by a fixed lingual wire bonded to each of the six anterior teeth in addition to an Essix-type removable appliance to be worn at night.

Case Presentation
A healthy forty-two year-old male presents for treatment with a chief complaint of crowded mandibular incisors. The labial position of the lower right central incisor was contributing to continued attrition (Figures 2a-h). His treatment objectives include a simple esthetic option to address his incisor crowding and minimize further attrition.

Following a thorough discussion of his treatment options, the SPEED lingual technique was selected. His nine months of active treatment was followed by a fixed mandibular retainer and removable overlay Essix appliance (Figs. 3a&b; 4a-e).

Conclusion
When used in the appropriate malocclusion, desirable results can be achieved using this simplified lingual technique. It is relatively simple, esthetic and eliminates the need for patient compliance. OH

Dr. Bruno L. Vendittelli is a Toronto-based orthodontist; Forest Hill Orthodontics and The Hospital for Sick Children.
www.foresthillortho.com

Footnotes
**Align Technology Inc., 881 Martin Ave, Santa Clara, CA 95050 www.invisalign.com
**SPEED Systems Orthodontics, Strite Industries Ltd., 298 Shepherd Ave., Cambridge, ON N3C 1V1. www.speedsystem.com
References
1. Kassab MM, Cohen RE. The etiology and prevalence of gingival recession. J Am Dent Assoc 2003; 134:20-225.
2. Sinclair P, Little R. Maturation of untreated normal occlusions. Am J Orthod Dentofac Orthop 1983; 83:112-23.
3. Moorees CFA. The dentition in the growing child: a longitudinal study of dental development between 3 and 18 years of age. Cambridge: Harvard University Press; 1959.
4. Sinclair P, Little R. Dentofacial maturation of untreated normals. Am J Orthod Dentofac Orthop 1985; 88:146-56.
5. Bishara SE, Treder JE, Jakobson JR. Facial and dental changes in adulthood. Am J Orthod Dentofacial Orthop 1994; 106:175-86.
6. Richardson ME. A review of changes in lower arch alignment from seven to fifty years. Semin Orthod 1999; 5:151-59
7. Little RM, Wallen T, Riedel R. Stability and relapse of mandibular anterior alignment. First premolar extraction cases treated by traditional edgewise orthodontics. Am J Orthod Dentofac Orthop 1981; 80:349-65.
8. Annual Report: The American Society for Aesthetic Plastic Surgery 2007.
9. Berger J, Byloff FK, Waram T. Supercable and the speed system. J of Clin Orthod. 1998; 32:246-53.

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