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Notes: Abstract  – The effect of temperature of various storage media and at varying storage periods upon periodontal ligament (PDL) and pulpal healing after tooth replantation was examined in green vervet monkeys (Cercopithecus aethiops). Mandibular lateral incisors with mature root formation were extracted and kept in dry storage at 22, 4 and −18 °C; in saline at 37, 22, 4 and −18 °C; or in saliva (i.e. in the buccal vestibule) at 37 °C for either 60 or 120 min prior to replantation. The animals were sacrificed 8 weeks after replantation and the replanted teeth examined histometrically. The following histological parameters were registered for each tooth: normal PDL, surface resorption, inflammatory resorption, replacement resorption (ankylosis), downgrowth of pocket epithelium, periapical inflammatory changes, and the extent of vital pulp. A total of 125 replanted teeth were examined. Storage in saliva at 37 °C showed a similar amount of normal PDL compared to saline storage for both 60 and 120 min. Saline storage for 60 or 120 min showed no difference in the extent of normal PDL when storage was compared at 37, 22 and 4 °C. However, storage at −18 °C resulted in significantly less normal PDL than storage at other temperatures. Dry storage for 60 min showed significantly less root resorption at 4 °C compared to 22 °C. Furthermore, dry storage at −18 °C showed significantly less normal PDL than storage at 4 °C. When the dry storage period was extended to 120 min, no difference was found between 22, 4 and −18 °C. It is concluded that the temperature (above 0 °C) of the storage medium is of importance only for dry storage and in such a situation only for shorter extra-alveolar periods, i.e. for 60-min storage and not for 120 min, where extensive destruction of the PDL always takes place. It is suggested that the temperature effect of 4 °C could be related to less evaporation from the PDL and thereby less damage to the PDL cells or a strict temperature effect upon cell metabolism. Pulp healing in all the cases was limited to the entrance of the pulp canal, and no significant pattern was found between storage media, time and temperature.

Notes: Abstract A material of 322 patients with 400 avulsed and replanted permanent teeth were followed prospectively in the period from 1965 to 1988 (mean observation period=5.1 yrs). The age of the patients at the time of replantation ranged from 5 to 52 yrs (mean =13.7 yrs and median =11.0 yrs). Standardized patient records were used through the entire period in order to obtain valid data concerning the extent of injury and treatment provided. At the follow–up period, pulpal and periodontal healing were monitored by clinical examination, mobility testing and standardized radio–graphic controls. Thirty–two of the replanted teeth (8%) showed pulpal healing. When related to teeth with incomplete root formation, where pulpal revascularization was anticipated (n = 94) the frequency of pulpal healing was 34%. Periodontal ligament healing (i.e. with no evidence of external root resorption) was found in 96 teeth (24%). Gingival healing was found in 371 teeth (93%). During the observation period, 119 teeth (30%) were extracted. Tooth loss was slightly more frequent in teeth with incomplete root formation at the time of replantation than in teeth with completed root formation.

Notes: Abstract – The objective of this in vitro study was to investigate the impact strength of anterior teeth that have been fractured and restored by bonding with a dentin-bonding agent and a composite resin. Twenty sheep central incisors were divided into two groups, 10 in each. One group (intact teeth) served as the control and the teeth in the other group were fractured and then bonded with a bonding agent and a low-viscous composite resin. The specimens were tested in a modified impact-testing machine (pendulum type). The mean impact strength of the intact teeth was 30.6±2.16 KJ/m2 and of the bonded teeth was 30.2±1.86 KJ/m2. Statistics revealed that the two means were not significantly different. The results related well with the fracture strength obtained by loading intact and bonded teeth at constant but low speed until fracture. It was concluded that bonding fragments to the remaining tooth structure may restore the tooth to its original strength, measured at modest velocities of the applied force. In other words, reattaching the original coronal fragment of traumatised fractured anterior teeth restored with One-Step dentin bonding system and Æliteflo composite resin would withstand a second trauma to the same extent as intact teeth.

Notes: Abstract— The extent of infraposition of replanted and subsequently ankylosed permanent incisors was examined in a longitudinal study of 52 patients. Study cast models were made during the follow-up period. Infraposition was evaluated on frontal photos of the study cast models taken parallel with the occlusal plane. The extent of infraposition was defined as the difference between the position of the incisal edge of the replanted incisor and the adjacent non-injured incisor in apicocoronal direction, measured with a digital caliper at 50 X magnification of the negatives. The precision of this measuring procedure was 2.9% and the accuracy 2.0%. Marked infraposition was identified if the tooth was traumatized before the age of 16 in boys and before the age of 14 in girls. In addition, infraposition was observed when ankylosis developed in patients aged 20–30 years, with a yearly mean infraposition rate of 0.07 mm/year (range: 0.02–0.21 mmlyear) in males and 0.07 mm/year (range: 0.00–0.12 mmlyear) in females. The latter findings supported the concept of slow continuous eruption of the teeth. This phenomenon may have implications not only for the treatment of traumatized teeth but also for the treatment of tooth loss by osseointegrated implants, which represent an analogue to the ankylosed replanted tooth.

Notes: Abstract— This in vitro study investigated the fracture strengths of fractured incisors after reattachment to the remaining tooth structure, using either Gluma dentin-bonding agent together with 1 of 13 different experimental resins or 1 of the following dentin-bonding agents: Gluma+ (experimental modification of Gluma), Panavia 21, ScotchBondl (SingleBond), All-Bondz, Dentastic, Super-Bond, Prime & Bond 2.1. No siwcant differences were found in the experiments with various experimental resins. The fracture strength of teeth rebonded with Gluma, All-Bondz, Dentastic, SuperBond or Prime & Bond 2.1 showed mean fracture strengths in the range of 8.7–11.2 MPa, which were significantly different in all cases from that of intact teeth (16.3 MPa). Teeth bonded with Gluma+, Panavia 21 or ScotchBondl (SingleBond) showed mean fracture strengths of 15.5, 14.6, and 14.2 MPa, respectively. These fracture strengths were not significantly different from that of intact teeth.

Notes: Abstract This study examined histologically the effect of three sealers used with gutta-percha as root-end fillings placed in a replantation model. A total of 14 molar teeth were used in seven monkeys. Alter extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared, and fillings of gutta-percha and sealer placed prior to replantation. After 8 weeks the teeth and surrounding Jaw were removed and prepared for histological examination. Six roots filled with gutta-percha plus a fortified zinc oxide-eugenol cement (IRM). 13 With gutta-percha plus zinc oxide-eugenol (EP), and eight with gutta-percha pins Kloropercha. were available for examination. The tissue response to gutta-percha with either Zinc oxide material was characterized by little or no inflammation of limited extent. In contrast, more severe inflammation was observed against root ends filled with gutta-percha and Kloropercha. Gutta-percha plus IRM or Zinc oxide-eugenol had a much more favourable response than that to amalgam reported previously in a similar experiment.

Notes: Abstract Four hundred avulsed and replanted permanent teeth were examined for pulpal healing. In 110 teeth, the apical foramen was either open or half-open. In 16 teeth, the pulps were extirpated prophylactically. Thus, pulpal revascularization was considered possible in 94 teeth. Revascularization occurred in 32 teeth (34%). Pulp necrosis could usually be demonstrated after 3 weeks. Positive pulpal sensibility and radiographis signs of pulp canal obliteration were usually observed after 6 months. The effect of various clinical factors was examined, such as sex, age, type of tooth replanted, stage of root formation, type and length of extra-alveolar storage, clinical contamination of the root surface, type of cleansing procedure of the root surface, type and length of splinting and the use of antibiotics. Finally, the width of the apical foramen and the length of the root canal were measured on radiographs taken at the time of injury. A multivariate statistical analysis revealed that pulpal revascularization was more frequent in teeth with shorter distances from the apical foramen to the pulp horns. Furthermore, that wet storage (saliva and/or saline) for more than 5 min decreased the chance of pulpal revascularization; whereas dry extraalveolar storage had a monotonous effect on pulpal revascularization, i. e. decreasing chance of revascularization with increasing length of the extraalveolar dry storage. Based on these findings, immediate replantation after brief cleansing in either tap water or saline is recommended.

Notes: Abstract –  According to treatment type, root-fractured teeth with pulp necrosis or exposed pulps were divided into five groups, group 1: 17 teeth in which the root canal of the coronal fragment only was filled with gutta-percha (GP); group 2: seven teeth in which the root canals of the coronal and apical fragments were both filled with GP; group 3: 19 teeth in which the coronal fragment was filled with GP and the apical fragment was surgically removed; group 4: 68 teeth where the root canal of the coronal fragment was treated with calcium hydroxide and subsequently filled with GP; and group 5: five vital teeth with root and concomitant crown fractures in which the exposed pulps were treated by partial pulpotomy. The frequency of periodontal healing was 76% in group 1, zero in group 2, 68% in group 3 and 86% in group 4. Compared with groups 1 and 2 combined, healing in group 4 was significantly more frequent. In groups 1, 2 and 4, failures occurred significantly more often in teeth showing overfilling, i.e. protrusion of GP into the space between the fragments, compared with teeth without overfilling. All five teeth in group 5 showed healing. It was concluded that root canal filling with GP of the coronal fragment only, with or without surgical removal of the apical fragment, can be successful in selected cases. Treatment of the root canal with calcium hydroxide followed by GP filling appears to be the treatment of choice in root-fractured non-vital teeth. Partial pulpotomy of exposed pulps in five teeth showed results similar to root-unfractured teeth with pulp exposure treated with this technique.

Notes: Abstract –  This is the second part of a retrospective study of 400 root-fractured permanent incisors. In this article, the effect of various treatment procedures is analyzed. Treatment delay, i.e. treatment later than 24 h after injury, did not change the root fracture healing pattern, healing with hard tissue between fragments (HH1), interposition of bone and/or periodontal ligament (PDL) or pulp necrosis (NEC). When initial displacement did not exceed 1 mm, optimal repositioning appeared to significantly enhance both the likelihood of pulpal healing and hard tissue repair (HH1). Significant differences in healing were found among the different splinting techniques. The lowest frequency of healing was found with cap splints and the highest with fiberglass or Kevlar® splints. The latter splinting procedure showed almost the same healing result as non-splinting. Comparison between non-splinting and splinting for non-displaced teeth was found to reveal no benefit from splinting. With respect to root fractures with displacement, too few cases were available for analysis. No beneficial effect of splinting periods greater than 4 weeks could be demonstrated. The administration of antibiotics had the paradoxical effect of promoting both HH1 and NEC. No explanation could be found. It was concluded that, optimal repositioning seems to favor healing. Furthermore, the chosen splinting method appears to be related to healing of root fractures, with a preference to pulp healing and healing fusion of fragments to a certain flexibility of the splint and possibly also non-traumatogenic splint application. Splinting for more than 4 weeks was not found to influence the healing pattern. A certain treatment delay (a few days) appears not to result in inferior healing. The role of antibiotics upon fracture healing is questionable.