Comparative evaluation of fracture resistance using two rehydration protocols for fragment reattachment in uncomplicated crown fractures

Abstract

Background/Aims Uncomplicated crown fracture is the most common traumatic dental injury. The International Association of Dental Traumatology has recommended fragment reattachment as the best method for restoring uncomplicated crown fractures of permanent teeth. Dehydration can affect fracture resistance after reattachment. However, a standard protocol for rehydration is still lacking. Hence, the aim of this study was to design a humidification chamber and assess its efficacy for improving the rehydration of tooth fragments and increasing fracture resistance after reattachment. Materials and Methods Sixty mandibular bovine incisors with similar dimensions and free of any structural deformities were fractured and randomized into five groups: Group I, Control Group (sound teeth); Group II (dehydrated for 24 hours); Group III (rehydrated in distilled water for 15 minutes); Group IV (rehydrated in a humidification chamber for 15 minutes); and Group V (restored with composite). A humidification chamber was designed and used for rehydration for 15 minutes in Group IV. Fragments in Group III were immersed in distilled water for 15 minutes. Reattachment procedures and materials remained the same in all groups. Fracture resistance was tested in a universal testing machine, and statistical analysis was done by Stata‐14. Results The Control Group with sound teeth (Group I) exhibited a maximum value of 282 ± 10.32 N, while Group II (fragment reattached without rehydration) had the least fracture resistance, 49.75 ± 5.2 N. Rehydration by means of the humidification chamber protocol (Group IV) resulted in significantly higher fracture resistance (150.54 ± 6.49 N) than in Group III (rehydration by means of immersion). Conclusions Fracture resistance after fragment reattachment was significantly affected by the rehydration of fragments for 15 minutes in the humidification chamber. Fragment reattachment after rehydration showed better fracture resistance than the composite restorations.

Comparison of three protocols for the management of re‐fracture of teeth with uncomplicated crown fractures

“…5,9 Although the treatment of choice for the management of uncomplicated crown fractures is fragment reattachment, the reattached fragments may also be dislodged due to repeated trauma episodes or abnormal occlusal forces. 5,6 Since there is a paucity of literature addressing this clinical paradigm, dentists are faced with a dilemma when a patient with a crown fracture managed by fragment reattachment reports with its dislodgement. The two conservative treatment options available in such situations involve performing a Several researchers have utilized bovine teeth in order to assess the efficacy of various protocols for fragment reattachment.…”

“…The sample preparation, until fragment reattachment, was carried out as per the protocol described by Madhubala et al (Figure 1). 6 Briefly, an ultrasonic scaler was used to clean the bovine teeth individually, the crown fracture was simulated by making a 5-mm fracture line on the labial surface by means of a diamond disc used parallel to the incisal edge and fracturing the tooth by applying a force perpendicular to the fracture line labiolingually. This was done by one operator who had prior experience with such experiments.…”

“…In a self-designed humidification chamber, which could result in 80 ± 2% humidity levels after an operational period of 10 minutes, the fragments were rehydrated for 15 minutes. 6 All of the fragments were dried by using a cotton roll, etching was performed by applying acid etchant (Scotch Bond Multipurpose etchant, 32% phosphoric acid, 3 M/ESPE, São Paulo, Brazil) for 30 seconds and washing with distilled water administered by a three-way syringe and air-dried for 10 seconds. A bonding agent (Adper Single Bond 2, 3 M/ESPE, São Paulo, Brazil) was applied to the etched surfaces using a micro-brush and light-cured for 10 seconds.…”

“…5 Madhubala et al evaluated the efficacy of two different rehydration protocols before bonding of the fractured fragment and highlighted that humidification for 15 minutes could result in significantly higher forces required to fracture compared with rehydration by immersion in distilled water. 6 It has been stated that injured teeth are more susceptible to further injury. [7][8] This along with aberrant occlusal forces, premature contacts and parafunctional habits can also result in fragment detachment or dislodgement.…”

Fragment reattachment after complicated crown‐root fractures of anterior teeth: A systematic review

“…[33][34][35][36][37][38] Most of the studies recommend rehydration for 15 to 30 minutes in a storage medium such as saline, distilled water or milk prior to bonding. 33,34,[36][37][38] A longer rehydration time of 24 hours prior to bonding was suggested by Farik et.al. 33 The current IADT guidelines suggest rehydration of a tooth fragment in water or saline for 20 minutes for uncomplicated crown fractures.…”