Restoration of incisal half with edge-up technique using ceramic partial crown in turner's hypoplasia: A case report.

This case report describes a rare treatment modality for Turner's hypoplasia done with a very conservative approach for the esthetic and functional problem of the defect. Diagnosis was made as Turner's hypoplasia of upper two central incisors with proximal caries. Treatment planning was done after considering many factors such as conservation of tooth structure, esthetics, occlusion and economy. Tooth preparation was done to receive Edge-up, all ceramic partial crowns for both the upper central incisors,using pressable all ceramic material and cemented with resin cement.

INTRODUCTION

Attractive smile is a prime asset to a person's powerful personality and it can be an important factor in the desirable life experiences of a human being. Dental esthetics, along with enhancing personality, helps in the general improvement of dental health which is founded on a more ethically sound basis. Esthetic dentistry demands attention to the patient's desires and treatment of the patient's individual problems. A practicing dentist must be acquainted with multiple factors associated with the esthetic treatment and must be aware of problems that such treatment may elicit or aggravate in the patient. Therefore, the patient's entire personal, familial, social environment along with the local factors must be considered in relation to esthetics.

Enamel hypoplasia (EH) is a defect in tooth enamel that results in less quantity of enamel than normal.[1] Traumatic injury to an anterior primary tooth that causes its displacement apically can also interfere with matrix formation or calcification of the underlying permanent tooth which is also called Turner's hypoplasia.[2] It usually manifests as a developmental defect of the permanent successor tooth, range from mild alteration in enamel mineralization in form of simple white or yellow brown discoloration to severe defective formation of enamel with loss of a portion of missing or severe pitting and irregularity of tooth crown, generally affecting one or more permanent teeth in the oral cavity.[34] It can cause a severe esthetic problem if it affects anterior teeth.

Treatment planning for patients with hypoplasia is related to many factors: The age and socioeconomic status of the patients, the type and severity of disorder and intraoral situation. Interdisciplinary approach is used to resolve esthetic problems using a combination of orthodontic, prosthodontic, and restorative treatment. Esthetic restoration of anterior teeth has been achieved with complete crowns, porcelain laminate veneers, and acid-etched composite resin restorations.[56]

A new therapeutic method named the edge-up technique developed by Fischer et al.,[7] has long-term experience with the facet technique, which allows treatment of defects in the anterior area with a maximum preservation of enamel. The name edge-up describes the principles and components of the restoration, edge focusing on the location, and set up aiming at the rebuilding of the incisal part of a tooth.

This case report describes a rare treatment modality for Turner's hypoplasia done with a very conservative approach for the esthetic and functional problem of the defect.

CASE REPORT

An 18-year-old female patient reported to conservative dentistry clinic with a chief complaint of mutilated front teeth compromising esthetics [Figure 1]. After taking an elaborate history which revealed that the patient had a trauma to the deciduous teeth when she was 1-year-old. Gingiva was inflamed and patient had edge to edge bite. On clinical intraoral examination, patient's oral hygiene was moderate with generalized gingival inflammation and partially mutilated and discolored upper central incisors. Vitality tests of all the teeth showed positive response for thermal and electric pulp testing indicating the vital status of the pulp. The radiographic examination showed no abnormality of the hard tissue at the periapical area. Diagnosis was made as Turner's hypoplasia of upper two central incisors with proximal caries. Treatment planning was done after considering many factors such as conservation of tooth structure, esthetics, occlusion, and economy.

Figure 1

(a) Pre-operative photograph showing Turner's hypoplasia of 11 and 21. (b) Post-operative photograph showing Ceramic edge-up partial crowns cemented. (c) Composite resin build-up of 11 and 21. (d) Tooth preparation to receive ceramic partial crown. (e) Temporary crowns cemented

During the initial appointment, thorough oral prophylaxis was done. Impressions were made with alginate impression material (Zelgan Plus, Dentsply India Pvt. Ltd, India). Study models were prepared. Proximal caries were removed and composite resin build up with Filtek™ Z250 (3M ESPE, Dental Products, St. Paul. U.S.A) was done to restore the hypoplastic defects and the carious defects. Tooth preparation was done to receive edge-up, all ceramic partial crowns for both the upper central incisors.[7] Deep chamfer finish lines were given using SC850-018, supercoarse, round end taper diamond point (IQ Dental Supply Inc.). Finish lines were kept at the junction of middle third and cervical third of the crown to include all the enamel defects and to also conserve the remaining healthy tooth structure to remain untouched. Tooth reduction was done for about 1 mm all around to accommodate ceramic material. Bite was corrected by occlusal contouring of the lower teeth. Secondary impressions were made using vinyl polysiloxane impression material (Dentsply Caulk, USA) and custom made acrylic temporary crowns were cemented with a zinc oxide eugenol (Dental Products of India, Mumbai, India) temporary luting cement material. Ceramic edge-up partial crowns were prepared using pressable all ceramic material (Cergo Kiss, Dentsply, India). Teeth were polished with pumice and cleaned thoroughly to remove eugenol, if any. Crowns were checked for occlusion and cemented with resin cement Rely X™ Veneer cement (3M ESPE, Puerto Reco). Crown margins were polished with ceramic polishing kit (Shofu, Inc., Japan) [Figure 2]. Six months follow-up showed the crown margins are in satisfactory condition [Figure 3].

Figure 2

Ceramic edge-up partial crowns cemented

Figure 3

6 months follow up photograph

DISCUSSION

The objectives of esthetic rehabilitation must be to provide the maximum improvements in esthetics with the minimum trauma to the dentition. Dentists and patients are fortunate at this particular time of interest in esthetic dentistry, since there are many materials and procedures available to patients and more are being developed all the time.

The treatment of dental problems of patients with EH presents an interesting challenge to dental surgeon. In Turner's hypoplastic types, enamel may be pitted, rough, or glossy.[6] The tooth is undersized and tapered toward incisal or occlusal surface and has open contact points.

Assessment of enamel thinness or absence, through use of dental radiographs, is not only used for diagnosis but also provides clinical information necessary for the development of an optimal treatment approach and to differentiate EH from dentinogenesis imperfecta and dentin dysplasia since clinical and radiographic appearance of these cases are similar. If there are esthetic concerns, with mild pitting or defect in the structure, microabrasion, direct or indirect composite or ceramic veneers, may be bonded to the affected tooth. For permanent anterior teeth, composite or porcelain veneers or porcelain crowns may be used.[8]

Ceramic crowns can correct shape, shade and texture can cause a remarkable change in a patient's self-image. Return of good physiologic form and function may also help prevent further deterioration of the mouth not only by preventing arch collapse, bone loss, and tooth and prepared to receive the full coverage. Moreover, crowns can produce poor gingival tissue response if the gingival contour is bad and if preventive gingival maintenance is not well. With metal-based crowns, the problem of detecting a recurrence of decay under metal is usually an additional problem.[9] Hence, in present case, we selected a conservative modality of edge-up partial crown with all ceramic material. This type of crown not only conserves the remaining healthy tooth structure but also helps to regain the form, function, and esthetics. In addition to the low possibility of pulpal irritation, margin placement is another advantage of enamel replacement restorations. Deep chamfer finish lines were chosen to accommodate ceramic material and to reduce the stress which is attributed to greater thickness. Deep chamfer can bear load better, making it more fracture-resistant. This finish line is recommended to improve the biomechanical performance.[10] The translucent ceramic that makes changing color difficult with these restorations also allows them to have invisible supragingival margins.[1112] Composite resin may not be a better choice in this case since there are severe malformation of incisal half of the affected teeth. Well-fitting crowns along with resin cements with proper shade match used for luting have merged the margins of crown well at the finish lines. We used resin cements for cementation, so we had a strong unity in the margins that provided smooth transition between tooth structure and crown and provided strength against fracture.[13] Polishing of the crown margins not only help to create a smooth transition of restoration to the tooth but also ease of maintenance of gingival tissue. Margins have to be polished well otherwise it may attract stains. Periodical refurbishing of restoration during the recall visit will be done for better prognosis.

However, long-term follow-up is required to evaluate the success of the edge-up crown. Success has to be evaluated after adapting this procedure in the posterior region too.

CONCLUSION

Partial edge-up crown is a conservative treatment modality for teeth with cervical part of the tooth structure is intact. Result obtained in this case with edge-up partial crown is very encouraging. With the advent of newer materials and techniques adapted, this treatment modality has given very good esthetic and functional results. The procedure holds promise for the successful management of partial defects of the teeth in the incisal/occlusal areas.