Returning a Child’s Smile:Adhesive Reattachment of a Tooth Fragment

Coronal fractures of the anterior teeth are a common form of dental trauma that mainly affects children and adolescents [1,2]. Approximately, one out of every four persons under the age of 18 sustain a traumatic anterior crown fracture [3,4]. Studies reveal that the most common injury to tooth is an uncomplicated crown fracture (fracture of the enamel and dentin without pulpal exposure). Majority of the fractures involved the maxillary central incisors, with boys outnumbering girls almost two to one [3,5,6]. During the last century, clinicians utilized a variety of procedures (e.g, pin-retained resin, orthodontic bands, modified three-quarter crowns, full-coverage gold with bonded porcelain, porcelain jacket crowns, porcelain bonded crowns, porcelain inlays) for the restoration of the fractured crown [7]. These earlier restorative procedures provided function only. Adolescents, maybe more so than adults, are prone to social and psychological implications as a result of the appearance from metal in the mouth, which can compromise aesthetics [8]. Recent developments in restorative materials, placement techniques, preparation design, and adhesive protocols facilitate restoration of fractured maxillary incisors. Early restorative materials (eg, silicates, acrylics) have been replaced by hybrid, microfill, and microhybrid composites. Traditional hybrid and microfill composites required the use of feather-edge, chamfer, shoulder, or long bevel preparation designs to facilitate the strength, sculptability, polishability, and durability provided by these materials. The feather-edge preparation required an overlay of composite resin that increased the volume of the composite on the labial and lingual enamel, which resulted in incisal breakdown, staining, and loss of retention [9]. The chamfer, shoulder, and long bevel preparation design provided a finish line and an increased volume of restorative material at the restorative margin, while maintaining the original contours of the tooth [10]. The concept of reattachment began in 1964 when Chosak and Eidleman used a cast post and conventional cement to attach an anterior crown segment on a 12 year old boy [11]. Anterior tooth fragments have since been reattached using composite, interlocking mini-pins , and light cure resins [12]. In the following years, various techniques have been described for reattachment of original tooth fragment using acid etch bonding various tooth preparation techniques, and a light and chemically cured composite resin [13]. No significant difference has been noted. However, in the fracture resistance of tooth prepared with a 45 degree external circumferential bevel, with no mechanical preparation for creation of “biological restoration” [14,15]. Tooth fragment reattachment offers a conservative, esthetic, and cost effective restorative option that has been shown to be an acceptable alternative to the restoration of the fractured tooth with resin-based composite or full-coverage crown [16, 17,18]. Reattachment of a fragment to the fractured tooth can provide good and long-lasting esthetics (because the tooth’s original anatomic form, color, and surface texture are maintained), [19] can restore function, can result in a positive psychological response, and is a reasonably simple procedure [20]. In addition, tooth fragment reattachment allows restoration of the tooth with minimal sacrifice of the remaining tooth structure. Furthermore, this technique is less time-consuming and provides a more predictable long-term wear than when direct composite is used [21]. Clinical trials and long-term follow-up have reported that reattachment using modern dentin bonding agents or adhesive luting systems may achieve functional and esthetic success [16, 22]. Several aspects may govern the choice of a reattachment technique. Studies have reported that the primary cause of fragment loss is new dental trauma or the non-physiological use of the restored tooth [6]. Therefore, most concerns about reattachment techniques have been directed toward the fracture strength of the restored tooth [23]. Clinicians have employed an assortment of bevel designs, chamfers, dentinal and enamel grooves, and choices of resin composite materials and techniques for the reattachment of tooth fragments. Reis and colleagues [5] have shown that a simple reattachment with no further preparation of the fragment or tooth was able to restore only 37.1% of the intact tooth’s fracture resistance, whereas a buccal chamfer recovered 60.6% of that fracture resistance; bonding with an over contour and placement of an internal groove nearly restored the intact tooth fracture strength, recovering 97.2 and 90.5% of it, respectively. In cases of complicated fractures, when endodontic therapy is required, the space provided by the pulp chamber can be used as an inner reinforcement, thus avoiding further preparation of the fractured tooth [24, 25].However, in such cases, esthetics may become an important issue as pulpless teeth lose part of their translucency and brightness. This article reports on two coronal tooth fracture cases that were successfully treated using tooth fragment reattachment.

Case: 1 A 9 year old girl reported to the Department of Pedodontics and Preventive Dentistry with the chief complaint of trauma in upper front tooth region due to fall from bed 1 week prior to presentation. The extra-oral examination revealed no significant findings. The clinical and radiographic maxillofacial examination indicated that the maxilla, mandible and other facial bones were intact. Intraorally, the maxillary left central incisor revealed complicated oblique crown fracture. The fracture line was oblique extending in apical direction from buccal to palatal surface. The margin on palatal surface was located about 2 mm from the free gingival margin and can be probed easily with a periodontal probe. In the periapical radiograph, apex was found to be open (Figure 2).

The crown fragment was brought by the patient. The apical fragment had no pathologic mobility. Other adjacent teeth had no sign of trauma and were vital. A detailed explanation about the treatment plan was given to the parent and patient and consent was taken. Local anesthesia was administered, and the fractured coronal fragment was immediately soaked in saline solution to prevent  further dehydration (Figure 3) . A decision was made to do MTA apexification followed  by  placement of a fiber-reinforced polymer post (Ribbond, Ribbond Inc. Seattle Washington, USA) into the root canal for retention. Following extirpation of the pulp tissue, MTA was plugged in open apex 3.5 mm (Figure 4) and sectional obturation  with gutta-percha and resin sealer was done. sealer (Sealapex®, Kerr Corporation, Orange California, USA).The day after the root canal treatment, Before reattachment, the fractured margins were checked to ensure an accurate fit. A small hole was created in the middle of the crown fragment in which to lay the polyethylene fiber. Isolation with respect to crevicular fluid seepage was achieved with cotton rolls and gauzes. Dual cure resin was used to secure fiber post (Figure 5).