August, 2011

Creating a new smile and a new life with Orthodontics

AUTHORS:

Dr. Vishal Seth

Post graduate student,

Department of Orthodontics,

Syamala Reddy Dental College

111/1 SGR College, Main Road,

Marathalli, Munekolala

Bangalore- 560037

Karnataka- India

E-mail: drvishal13@rediffmail.com

 

Dr. PRASHANTH KAMATH

BDS, MDS

Professor and Head of Department,

Department of Orthodontics,

Syamala Reddy Dental College

111/1 SGR College, Main Road,

Marathalli, Munekolala

Bangalore- 560037

Karnataka- India

 

Dr. RENU PRASAD

BDS, MDS

Associate  Professor,

Department of Orthodontics,

Syamala Reddy Dental College

111/1 SGR College, Main Road,

Marathalli, Munekolala

Bangalore- 560037

Karnataka- India

Dr. VISHWANATH

BDS, MDS

Senior Lecturer,

Department of Orthodontics,

Syamala Reddy Dental College

111/1 SGR College, Main Road,

Marathalli, Munekolala

Bangalore- 560037

Karnataka- India

 

 

ABSTRACT:

 

Orthodontics is an art and a science. In addition to “straightening” teeth, orthodontists are also artists in creating the smile. Smile analysis is an important stage for the diagnosis, planning, treatment and prognosis of any dental treatment involving esthetic objectives. The evaluation of the intrinsic characteristics of the smile is a necessary procedure to achieve consistent form in orthodontic treatments, which in turn makes it necessary to recognize the components and factors that affect these characteristics. The goal of orthodontic treatment is to properly align the teeth, lips and jaws to create a balanced, pleasing facial appearance and ensure that the teeth and jaws are functioning normally.

 

KEY WORDS: Smile, Orthodontics. Dental esthetics

 

INTRODUCTION:

Aristotle said “Beauty is a greater recommendation than any letter of introduction”. A statement that is true nowadays where attractive people have a much better chance of being successful. Dentists and orthodontists can greatly contribute to enhancing patient’s smile, appearance, and subsequently their self-confidence. Today’s “art of the smile” is being driven by the orthodontist’s ability to clinically examine the patient in 3 dimensions and use the latest technology to document, define, and communicate the treatment strategy to patients and colleagues involved in interdisciplinary care. A smile is defined and described differently by different dental specialists.^1-7 Malposed teeth, damaged by trauma or congenitally malformed teeth are in need of orthodontics and/or esthetic reconstruction. Therefore, it is essential that the clinician has a comprehensive knowledge of the elements and basic principles of esthetics and the specific characteristics of the individual’s teeth. The term esthetics refers to an understanding of beauty. Therefore, it is required to have an understanding of beauty and the artistic tools available to develop a beautiful smile⁸.

 

CONSIDERATIONS FOR THE ESTABLISHMENT OF AN ESTHETIC SMILE:

Orthodontic treatment involves many variables, such as growth patterns, muscular habits, and patient compliance. Certain time-tested requirements for long-term stability should be addressed during treatment planning. The goal is to place the teeth in a particular position that will produce the most functional, esthetic, and stable results possible. Throughout the history of orthodontics, certain truths have been found that set the standard for high-quality results. The challenge is to apply the new technology to create results that meticulous science has already proven possible. Several benchmarks have been established:

 

1. It is important to control the position of the mandibular anterior teeth. Uncontrolled flaring will certainly lead to post-treatment relapse.

2. When the roots are not spread properly, incisors tend to crowd.

3. Expanded mandibular canines typically constrict after the removal of retention.

4. Insufficient torque in the maxillary incisors tends to lead to relapse.

5. In deep bite cases, the mandibular first molars should be uprighted to level the arch and help prevent relapse of the arch.

6. The soft tissue profile should allow the lips to gently touch when relaxed.

 

OBJECTIVES FOR CREATING AN ESTHETIC SMILE:

As the teeth are positioned in basal bone, labiolingually, the clinician should also be considering the way in which the lips frame the teeth. By beginning with the end in mind, the orthodontist can produce a symmetrical smile^9-11 while addressing these objectives. To ensure the creation of the best possible smile, at least 10 objectives should be addressed:

 

1. Facial and dental midlines: The median plane is a line passing longitudinally through

the middle of the body from front to back, dividing it into the right and left halves. The facial midline is a critical reference position for determining multiple design criteria¹²

in orthodontic treatment planning,¹³ as it is an important functional component of occlusion.¹⁴ In a totally symmetrical face, the dental midline and the facial midline should coincide. The midline is observed by relating the facial midline and cupid’s bow

of the upper lip to the maxillary central incisor midline. The mandibular dental midline is then matched with the maxillary midline (Fig 1). Studies have shown that a slight deviation of the midline^9-11,15-18 is not disconcerting to an individual’s appearance. Most midline deviations can be corrected after the finishing archwires are in place.

 

 

2. Tooth Size : Tooth size is important for both dental and facial esthetics. Teeth should be proportionate to each other and proportionate to the face.¹⁸ When the width of a tooth and its neighbor in the anterior segment are considered, the ratio of 1:618 has been judged to be the most esthetically pleasing. This is called the Golden Proportion.¹⁹ Levin²⁰ developed a dental grid for the anterior segment to facilitate dental esthetics.( Fig 2). In orthodontics, the Golden Proportion is helpful when slenderizing and dealing with small or peg-shaped maxillary lateral incisors. When teeth are too small, the profile is affected. The orthodontic patient is offered the opportunity to decide whether spaces should be left to allow future restorative enlargement of the teeth. The Golden Proportion is determined by using the Golden Rule template developed by Dr Tom Dawson.( Fig 3 )

 

 

3. Tooth Angulation: The angulation of the maxillary and mandibular anterior teeth, canine to canine, has a dramatic effect on the patient’s appearance during smiling. Spreading the maxillary and mandibular anterior roots has been common in orthodontics at least since the beginning of the Tweed technique,²¹ when Tweed taught his students to use “artistic positioning bends.” Today these bends are incorporated in the design of the bracket prescription. If this prescription is followed, the teeth are not only more esthetically pleasing, but also found to be more stable . ( Fig 4)

 

 

4. Cant of the Occlusal Plane: Slight deviations in incisal plane symmetry has been shown to be less esthetic.¹⁵ This plane should be parallel to the upper lip and eyes.( Fig 5) The cant of the occlusal plane can be corrected  by the use of continuous symmetrical archwires (not segmented), the application of symmetrical forces (such as a cervical facebow), and the efforts of the patient to squeeze the teeth together to distribute symmetrical occlusal forces.

 

 

5. Smile Line: The smile line is the incisogingival position of the upper lip in relation to the maxillary anterior teeth when an individual is smiling. The stomion-incisor measurement represents the cephalometric position of the upper lip in relation to the incisal edge of the clinical crown.¹⁵ At rest, this distance should be about 4 to 5 mm. When an individual is smiling, the upper lip should be positioned within 2 mm above or below the gingival line. Normally, women have higher smile lines²¹ and men have lower smile lines. This measurement decreases with age. Tjan et al¹⁶ arranged smiles into three categories: low smile, average smile, and high smile (Fig 6). A high smile is one that reveals the total cervicoincisal length of the maxillary anterior teeth and a contiguous band of gingiva. An average smile would be classified as a smile that reveals 75% to 100% of the maxillary anterior teeth and the interproximal gingiva. A low smile displays less than 75% of the anterior teeth. The smile line can be controlled or improved. With good mechanics and favorable growth, impressive changes can be achieved. Attempts to intrude the maxillary anterior teeth in effect “hold” the teeth in place as the maxilla grows. Anterior teeth can also be extruded, tipped, or erupted with stable results.

 

 

 

6. Gingival Line: The gingival line is the relationship of the maxillary anterior teeth to the position of the gingival tissue covering them. The goal is to have the gingival margins of the central incisors and canines at the same level and those of the lateral incisors slightly lower. Realistically, the orthodontist’s goal is to properly position the clinical crowns; usually the gingival line will adapt spontaneously.

 

7. Buccal Corridors: Dark buccal corridors refer to the dark (negative) spaces created

between the corners of the mouth and the buccal surfaces of the maxillary teeth during smiling. Johnson,²¹ Bowman,²² and Mackley²³stated that the size of the buccal corridor showed no correlation to prior premolar extraction. They emphasized that patients with better esthetic scores had a significantly greater frequency of visible maxillary first molars. To control the buccal corridors, three objectives must be achieved. (Fig 7)

 

1. Development of an ovoid maxillary arch form

2. Adequate expansion in the premolar and molar regions

3. Mesiobuccal rotation of the maxillary first molars per prescription to fill the buccal corridors with enamel and eliminate the dark spaces.

 

 

 

8. Smile Arc: The position of the maxillary incisal edges in relation to the smiling lower lip creates the smile arc (Fig 8) The ideal position for incisal edges is the wet-dry line of the lower lip. The smile arc is related to the incisal length and lip musculature. It is initially affected by bracket placement, archwires, and elastics. Ideally, the maxillary incisal edges should follow the curvature of the lower lip, resulting in parallelism.^16,23

At the end of treatment, the smile arc can be adjusted with finishing elastics.²⁴

 

9. Finishing: The finishing touch also includes taking the extra step to polish the enamel with polishing burs and cups after bracket removal. In addition, the incisal edges are leveled with special diamond burs at the time appliances are removed.

 

10. Tooth Color: Tooth color plays a very important role in contemporary dental esthetics. Dunn et al²⁵ found that tooth shade is an important factor in predicting attractiveness. The trend for whiter and brighter teeth has become so popular that cosmetic dentistry has become the mainstay in many of today’s dental practices. Bleaching can be recommended for every adult patient who desires whiter teeth at the end of treatment and these patients can be referred for esthetic dental work if needed.

 

CONCLUSION:

The smile should be analyzed from the frontal view to achieve the goals of symmetrically framing the teeth with the lips and harmonizing the teeth, gingiva, negative space, and lips. The lips are the frame, the teeth are the main subjects, and the gingiva is the background. In the vast majority of growing, cooperative patients, the smile can be greatly improved with orthodontic treatment. The objective is to treat asymmetries by applying symmetrical forces. This includes the use of continuous, tied-back, ideally shaped archwires in each arch, a symmetrically designed facebow, a face mask, and/or a lip bumper. To obtain the desired results, it is important to select the accurate force vector for the orthopedic appliance, to create an accurate arch form, and to place proper curves in the archwires. Elastics are then used to finalize centric relation and centric occlusion, midline, overbite, and posterior occlusion. Following these principles will allow the orthodontist to systematically and consistently deliver high-quality, stable results with beautiful smiles.

 

 

REFERENCES

 

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7. Ackerman JL. The emerging soft tissue paradigm in orthodontic diagnosis and treatment planning. Clin Orthod Res 1999;2:49-52.

 

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Tags: Orthodontics. Dental esthetics, Smile