|Year : 2014 | Volume
| Issue : 3 | Page : 124-126
Orthodontic-restorative treatment of maxillary midline diastema
Mahboobe Dehghani1, Farzin Heravi2
1 Dental Research Center, Department of Orthodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
2 Dental Materials Research Center, Department of Orthodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
|Date of Web Publication||15-Jul-2014|
Assistant Professor of Orthodontics, Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad
Source of Support: Mashhad University of Medical Sciences, Mashhad, Iran, Conflict of Interest: None
Introduction: Maxillary midline diastema in adults is an esthetic problem that alters the appearance of smile. This paper describes treatment of a large diastema in a middle-aged patient. Case Report: The case was a 52-year-old woman with a large median diastema and congenitally missing maxillary lateral incisors. A combined orthodontic and prosthetic approach was used to close the diastema and open up space for substitution of missing laterals by implants. Discussion: Despite the slow rate of tooth movement in adults, a large diastema was closed. This interdisciplinary approach improved the esthetic aspect greatly. The patient was satisfied even after four-years of follow-up period.
Keywords: Case report, diastema treatment, midline diastema, missing laterals
|How to cite this article:|
Dehghani M, Heravi F. Orthodontic-restorative treatment of maxillary midline diastema. Dent Hypotheses 2014;5:124-6
| Introduction|| |
Maxillary midline diastema was described by Keene as anterior midline spacing greater than 0.5 mm between adjacent teeth which can be an esthetic problem.  Incidence of midline diastema varies with age. Taylor reported that about 97% of five-year-old children have midline diastema which decreased with age.  Weyman and Gardiner reported that the incidence of midline diastema in children between six to eight years of age is nearly 50% which decreased to approximately 6% by age 15. , After complete eruption of permanent dentition continued presence of diastema is considered a problem. It has an unwanted effect on appearance and patients usually complain of their appearance with a desire to close the diastema. 
There are some major etiologic factors for median diastema such as high frenum attachment, midline bony clefts, microdontia, and pegged or missed lateral incisors.  Management of midline diastema due to missing lateral incisors often needs a multidisciplinary approach. Management of each patient depends on a number of factors such as skeletal pattern, tooth size space analysis, and available anchorage. 
The case presented describes an old age, partially edentulous woman who had complained about the appearance of her maxillary anterior teeth because of a large midline diastema and missing lateral incisors. This case report demonstrates an interdisciplinary approach including orthodontic and prosthodontic treatment for the rehabilitation of large maxillary diastema.
| Case Report|| |
Our patient was a 52-year-old woman admitted to the Department of Orthodontics, School of Dentistry, Mashhad University of Medical sciences, Iran, to address her congenitally missing lateral incisors and closing the large gap between the anterior teeth. She was embarrassed during smile and speech. She had a symmetric face, harmonious profile, and competent lips. During posed smile, less than full length of her incisors were shown [Figure 1]. All procedure was described, and informed consent was written by subject.
Mandibular and maxillary right first molars were lost. Maxillary lateral incisors were missed congenitally and maxillary left first molar and both maxillary second premolars had porcelain fused to metal (PFM) crown restorations. Rotation of maxillary canines and first premolars along with a 6 mm diastema with right class I and left half cusp class II molar relationship could be mentioned as her other dental characteristics.
Treatment objectives and treatment alternatives
There are two major options for treatment of patients with maxillary missing lateral incisors: 1. Space closure by mesial movement of canines and posterior teeth; 2. Opening space for prosthetic replacement of teeth. Large spaces in the arch made the first choice unlikely. Therefore, we decided to close the diastema and make an appropriate space for the implant of missing lateral incisors.
Treatment design and progress
Standard edge-wise steel brackets with 0.018 inch slot (Dentaurum, Ispringen, Germany) were placed on the teeth and a self-fabricated transpalatal arch (TPA) were inserted to reinforce anchorage. Order of arch wires was 0.014 NiTi, 0.016 NiTi and 0.016 stainless steel (Ortho Technology Inc, Florida, USA).
Chain elastics (Ortho Technology Inc, Florida, USA) were used to bring central incisors in contact. In sequence, open coil springs (Ortho Technology Inc, Florida, USA) were placed between central incisors and canines. We had a two-months delay before initial movement, then, after three months, adequate space of about 7 mm each side was produced [Figure 2].
At this time, patient was referred to a periodontist for implant fixture placement. At the same time circumferential supracrestal fibrotomy (CSF) around the upper central incisors was done for more retention. We made a permanent retainer by 0.017 multi-stranded wire (Dentaurum, Ispringen, Germany) on the palatal surface of the central incisors with an advice to wear a Hawley retainer till six months after debonding. After completion of implants, the esthetic aspect of the mouth was enhanced greatly [Figure 3]. A four-year follow-up showed good smile esthetics with negligible relapse.
| Discussion|| |
Adjunctive orthodontic treatment for adults is usually carried out to facilitate other dental procedures such as restorations.  The described patient was an adjunctive treatment case. She exhibited a median diastema and congenitally missing lateral incisors. By interdisciplinary treatment diastema was closed and missing lateral incisors were replaced by implants.
The presented case was partially edentulous since maxillary right molars were lost. In addition some teeth had PFM restorations so anchorage was impaired. Furthermore, correction of rotated teeth requires enough anchorage. In order to reinforce anchorage, a TPA was inserted so that premolar on one side was connected to other side molar.
Moreover, the diastema was large and patient was relatively old. There is debate and controversy about rate of orthodontic tooth movement in adults. According to Nanda, tooth movement in adults is with some delay in comparison with younger patients.  This was true for the patient presented in this article; two-months delay prior to starting teeth movement but after that the rate was nearly normal.
In cases with congenitally missing lateral incisors, two main approaches commonly taken are space opening or space closure.  Decision depends on some factors like: Arch-length deficiency, and facial profile. With space opening various replacement options are available. Since the advent of osseointegrated implants, the resin-bonded bridges are no longer the treatment of choice for such patients. Missing lateral incisors of our patient were replaced by implants and after four-year follow-up, implants and adjacent teeth did not show any complication.
Orthodontic treatment for adults has more difficulties in comparison to adolescents. Doubt about rate of tooth movement, compromised periodontal condition and anchorage, multiple porcelain restorations, reduced adaptation, relapse, and interactions with other specialists are some concerns in treatment of adults. Orthodontists are not inclined to adjunctive orthodontics. With current progresses on bonding to porcelain restorations, adults orthodontics has been facilitated.  Contrary to common belief that in olders occlusal function is important and esthetic has little effect on quality of life, it is important for adults too.  Our patient was very happy and satisfied with esthetic results of the treatment. She could smile with confidence after nearly 50 years and said "I smile and speak easily and don't cover mouth by hand".
Finally, it should be noted that stability of closure of diastema is suspected and permanent retention with bonded retainer has been suggested. ,, Zachrisson recommended multi-stranded wire retainers in difficult retention situations.  Considering the above we chose multi-stranded wire as permanent bonded retainer to the central incisors.
| References|| |
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[Figure 1], [Figure 2], [Figure 3]