Effect of minocycline on healing of replanted dog teeth after extended dry times

Abstract  – Minocycline is available as a locally administered tetracycline derivative antibiotic (Arestin™, OraPharma, Inc., Warminster, PA, USA) which demonstrated antibacterial activity and anti-inflammatory action that may slow down resorptive processes after severe traumatic injuries to the dentition. A total of 48 premolar roots of six mongrel dogs were instrumented in an aseptic fashion with rotary nickel-titanium files and obturated with vertically condensed warm gutta percha. All accesses were sealed with glass ionomer, the roots extracted and then allowed to bench dry for 60 min. Group 1 consisted of 15 roots that were coated with minocycline and replanted and nine roots that were replanted without minocycline. Group 2 consisted of 24 roots, all of which were prepared with a uniform cemental defect down to sound dentin along the lateral aspect of the root, with a high-speed bur following the 60-min dry time. Half of the roots ( 12 ) were then coated with minocycline and replanted, and the other 12 roots were replanted without minocycline. After 4 months, the dogs were killed and the roots prepared for histological evaluation. About 5-µm thick cross-sections of the root and surrounding tissue taken every 90 µm were evaluated for healing. In addition, residual root mass was also measured in the roots of group 1 to determine the extent of root structure loss for each treatment method. The roots with and without minocycline treatment showed no significant differences between the remaining root mass or the percentage of favorably healed root surfaces. The use of minocycline is not currently recommended for prevention or attenuation of external root resorption following avulsion in a dog trauma model.     

Effect of systemic tetracycline and amoxicillin on inflammatory root resorption of replanted dogs' teeth

Abstract— The use of systemic penicillin after an avulsion injury has been recommended as a way to decrease the occurrence of resorption complications. Our previous study has shown systemic tetracycline to possess anti-resorptive properties independent of potential anti-bacterial actions. The purpose of this study was to compare histologically the effectiveness of tetracycline and amoxicillin in limiting inflammatory root resorption (IR) secondary to pulpal infection, in replanted dogs' teeth. Thirty root canals in five dogs were infected with plaque. The roots were extracted, the lingual mid-roots were shaved with a fissure bur ensuring cemental damage and immediately replanted. Dogs were given either tetracycline hydro-chloride or amoxicillin, administered orally, on the day of extraction and replantation and for the following 6 days. The control group was teeth in these animals treated in the same manner but where no antibiotics were given. After approximately 6 months, the dogs were sacrificed and the teeth prepared for histologic evaluation. The shaved root surface was identified in cross-sections and eight equidistant points along the cut root surface were evaluated for healing (H) or IR in eight sections per tooth. For the tetracycline group, H averaged 67.22% and IR 32.!8%, which was not statistically different from the amoxicillin group with H averaging 56.88% and IR 43.12%. The tetracycline group was superior to the control group with H= 27.86% and IR=72.14%. Since tetracycline has been shown to have anti-resorptive properties in addition to the antibacterial properties demonstrated here, it could be considered as an alternative to amoxicillin after avulsion injuries.     

The effect of systemic tetracycline on resorption of dried replanted dogs' teeth

Abstract— The use of systemic penicillin after an avulsion injury has been recommended to decrease the occurrence of resorption complications. Tetracycline antibiotics have been reported to possess anti-resorptive propemes in addition to their anti-microbial actions. The purpose of this study was to evaluate histologically the effect of systemically administered tetracycline and amoxicillin on the inhibition of resorption due to attachment damage after replantation of dogs' teeth. Thuty-one roots from the teeth of four beagle dogs were endodontically treated to inhibit subsequent inflammatory root resorption of pulpal origin. They were then extracted and left to bench dry for 1 h to ensure severe periodontal ligament damage before replantation. For the teeth in the experimental groups, two dogs were given tetracycline hydrochloride and the other two dogs were given amoxicillin, administered orally, on the day of extraction/replantation and for the following 6 days.
The control group were teeth in these animals treated in the same manner but where no antibiotics had been given. After 12–16 weeks, the dogs were sacrificed and histological sections were prepared and evaluated for complete healing, inflammatory and replacement root resorption, and the groups were compared. It was shown that healing in the amoxicillin and the control groups was poor (10.90% and 11.28%, respectively), while for the tetracycline group, 35.45% showed complete healing. Individual teeth with over 50% complete healing sites were considered as having good healing, and sigdicantly more of these teeth were found in the tetracycline group (5 of 11 teeth) compared to the amoxicillin (1 of 11 teeth) or control group (1 of 8 teeth).     

Effect of immediate intracanal placement of Ledermix Paste® on healing of replanted dog teeth after extended dry times

Abstract  – Ledermix Paste^® is a paste containing triamcinolone and demeclocycline with demonstrated anti-inflammatory activity that may slow down resorptive processes after severe traumatic injuries to the dentition. A total of 29 premolar roots of six mongrel dogs were extracted and instrumented with rotary nickel titanium files. Fifteen of these roots were then filled with a calcium hydroxide (Ca(OH)₂) slurry and 14 roots were filled with Ledermix Paste^® paste. All accesses were sealed with glass ionomer and the roots replanted after an extraoral dry time of 60 min. After 4 months, the dogs were killed and the roots prepared for histological evaluation. Five-micrometer thick cross-sections of the root and surrounding tissue taken every 90 µm were evaluated for healing. In addition, residual root mass was also measured to determine the extent of root structure loss for each treatment method. The Ledermix Paste^®-treated roots had statistically significantly more healing and less resorption than the roots treated with Ca(OH)₂. Root filling with Ledermix Paste^® also resulted in significantly less loss in root mass due to resorption compared to those roots filled with Ca(OH)₂. Immediate intracanal placement of Ledermix Paste^® at the emergency visit after an avulsion injury appears to decrease resorption and increase favorable healing.     

Long‐term retention of avulsed maxillary permanent incisors replanted after prolonged non‐physiological storage

Ankylosis and external replacement resorption (ERR) are two typical biological responses to delayed replantation of avulsed teeth in cases where adequate root canal treatment is performed. The patient's growth stage affects the progression of root resorption and the long‐term outcome of the affected teeth. This case report describes the long‐term outcome of an 18.5‐year‐old patient following an accident in which both of his maxillary central incisors were avulsed and replanted after four hours of non‐physiological storage. ERR and ankylosis of teeth 11 and 21 were detected clinically and radiographically during the second year of follow‐up. Sixteen years after replantation, replacement resorption was progressing very slowly, enabling functional tooth retention with favorable esthetics. Young adults, with delayed replantation of avulsed teeth, may benefit from tooth retention with slow ERR.     

Effect of enamel matrix derivative (EMDOGAIN®) upon periodontal healing after replantation of permanent incisors in Beagle dogs

Abstract – This study histologically assessed the effect of enamel matrix derivative (EMDOGAIN^®) on periodontal healing in re-implanted teeth in nine Beagle dogs. Incisors in dogs were re-implanted after 15, 30 and 60 min of dry storage with and without the application of EMDOGAIN. The pulps were removed in all teeth. In groups 1 and 2, dog teeth were splinted and the dogs sacrificed after 8 and 12 weeks, respectively. In group 3, dog teeth were not splinted and sacrifice took place after 12 weeks. The histological parameters studied were healed PDL, surface, inflammatory and replacement resorption. Univariable and multivariable analysis of data was performed. Increased incidence of healed PDL was inversely proportional to extraalveolar time. No significant differences were noticed between splinted and non-splinted teeth. The EMDOGAIN group showed a higher incidence of healed PDL, while controls showed a higher incidence of ankylosis. The effect of EMDOGAIN was more pronounced at the 12-week interval.     

Effect of topical alendronate on root resorption of dried replanted dog teeth

Abstract – Alendronate (ALN) is a third generation bisphosphonate with demonstrated osteoclast inhibitory activity that may slow down the resorptive process after severe traumatic injuries. Eighty-two premolar roots of five mongrel dogs were endodontically treated and restored, extracted and treated as follows: 70 roots were bench dried for either 40 or 60 min. Thirty-eight of these roots were then soaked for 5 min in a 1 mM solution of ALN in Hanks' Balanced Salt Solution (HBSS) and replanted. Thirty-two roots were soaked for 5 min in HBSS and replanted. In the remaining 12 roots which were not exposed to the bench drying procedure, a 0.5 mM deep lingual mid-root cemental defect was made. Six of these roots were soaked in a 1 mM solution of ALN in HBSS for 5 min and replanted. The other six roots were soaked for 5 min in HBSS and replanted. Historical negative and positive controls were used from similarly treated teeth in our previous studies. After 4 months the dogs were killed and the roots prepared for histological evaluation. Five-μm-thick cross-sections of the root and surrounding tissue taken every 70 μm were evaluated for healing according to the criteria of Andreasen. In the 12 roots with cemental defects, healing with cementum of the damaged root surface was evaluated. In addition, residual root mass was also measured to determine the extent of root structure loss for each soaking method. Cemental healing took place in all 12 artificially damaged roots, indicating that these soaking media did not inhibit cementogenesis. The alendronate-soaked roots had statistically significantly more healing than the roots soaked in HBSS without alendronate. This improvement in healing was seen in all dogs except one and in all teeth except the first premolar. Soaking in alendronate also resulted in significantly less loss in root mass due to resorption compared to those teeth soaked in HBSS without alendronate.     

Periodontal healing of extracted dogs' teeth air-dried for extended periods and soaked in various media

Abstract The aim of this study was to determine the periodontal healing of replanted dogs’ teeth which, after extended extra-oral dry times, had been soaked in various media before replantation. Incisors and premolars of beagle dogs were root canal treated, extracted and bench dried. The teeth were grouped according to dry times of 30, 45 and 60 minutes. Each group of teeth was soaked in one of three media, Hank's balanced salt solution, Via Span (Belzer UW-CSS, Dupont Pharmaceuticals), or Conditioned Medium (supernatant of confluent culture of human gingival fibroblasts) for 30 minutes before replantation. Controls consisted of teeth extracted and replanted without drying or soaking (negative control), and bench-dried teeth replanted without soaking in the media (positive control). The dogs were killed 6 months after replantation of the teeth, which were prepared for histologic evaluation. Five um cross-sections (every 70 Jim) of the root and surrounding tissue were evaluated for healing/resorption according to Andreasen's criteria. The best healing occurred for the roots which had been immediately replanted. Healing in the positive control groups decreased with increased dry time. For the 30–minute dry time groups, soaking in media had no beneficial effect on periodontal healing compared with the controls. Soaking in ViaSpan resulted in an increased healing incidence for both the 45- and 60- minute bench-dried groups while soaking in the other media had no consistent beneficial effect. It appears from this study that an avulsed tooth that has been left dry for 30 minutes should be replanted immediately without soaking. However, teeth that have been dry for 45 or 60 minutes would benefit from soaking for 30 minutes in ViaSpan.     

Replacement of severely traumatized teeth with immediate implants and immediate loading: literature review and case reports

One of the options for management of severely traumatized dentitions is to provide immediate implant placement with immediate loading. Three representative cases out of 15 patients with 23 traumatized teeth treated to date in our clinic are presented. None had labial bone fractures. The teeth were replaced with NobelReplace Groovy implants (Nobel Biocare, Gothenburg, Sweden) in the fresh sockets immediately after extraction. They were placed toward the palatal areas in the sockets and 3 mm below the gingival margins. If there were gaps between implants and sockets wider than 1 mm, particulate deproteinized bovine bone was grafted in the gaps. Immediately after placement, the implants were loaded with provisional prostheses. The final restorations were installed 3–4 months later. The patients were reevaluated clinically and radiographically 1–3 years after the final restorations had been placed. In all 15 patients, excellent functional and esthetic results were achieved. No implants showed radiolucency, peri‐implant suppuration, or mobility. The patients were satisfied with the results. Immediate implant placement with immediate loading is an option that provides good treatment outcomes and allows good functional and esthetic results, as well as addressing the social/psychological aspects of dental trauma.     

Relationship between clinical–radiographic evaluation and outcome of teeth replantation

Abstract –  The aim of this retrospective study was to evaluate clinical and radiographic results related to avulsed and replanted teeth in patients who sought treatment at the Dental Trauma Center of the Dental School of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil. One hundred replanted teeth were studied from 48 individuals (18 females and 30 males, with a mean age of 15 years and 9 months). Post-replantation factors (clinical and radiographic) were observed. The clinical aspects evaluated were crown discoloration, pulp necrosis, mobility changes, presence of fistulae and tooth infra-position. Radiographic examination aimed to identify replacement and inflammatory root resorptions, pulp canal obliteration and the presence of radiolucent areas. Depending on clinical and radiographic findings, results were classified as: complete success, acceptable success, uncertain success or failure. During anamnesis, other factors such as stage of root formation, period extra-alveolar, storage medium, type of splintation, and period after replantation time were recorded. The data obtained were statistically analyzed in order to determine the relationship between the post-replantation factors and outcome of teeth replantation. Linear logistic regression revealed that the majority of replanted teeth were associated with root resorptions and its occurrence duplicated proportionally as the time after replantation increased. Based on these findings, replantation procedures must be submitted to an accurate follow-up, as the success of replanted teeth, which already tends to be limited, may be even more jeopardized if cases are not controlled.     

Applications of basic fibroblastic growth factor (FGF‐2, bFGF) in dentistry

Recent developments in research have been based on the maintenance and regeneration of natural organs and tissues; among such developments is the use of growth factors (GFs). The use of basic fibroblastic growth factors (bFGF) may be indicated in different disciplines of dentistry such as periodontics and dental traumatology. These cells' ability to induce proliferation and differentiation of cells may make GFs a useful source for the development of natural structures. This mini‐review will discuss how bFGF can be beneficial to dentistry in relation to 1) re‐implantation/autotransplantation of avulsed teeth and 2) periodontal regeneration.     

Factors affecting the time of onset of resorption in avulsed and replanted incisor teeth in children

Abstract – Resorption is the main reason for loss of replanted teeth. The outcome examined in this study is the timing of the onset of resorption. The effect of dichotomised dry and wet time intervals as well as the presence of additional crown damage and of contamination were determined. Of 84 replanted teeth, 67.5% developed resorptions. Twenty-eight had detectable additional crown damage with a more rapid onset being seen in these cases ( P =0.009). The critical limit for dry time was 15 min ( P =0.038) and significant differences persisted for greater limits also. Serial analysis of the association between the time of onset of root resorption and dichotomised wet time variables failed to yield any significant associations. There was visible contamination detected in 32 teeth and these exhibited a more rapid onset of resorption than the other cases ( P =0.030). Teeth with inflammatory root resorption (12.8%) had a more rapid onset of resorption than those that developed replacement resorption (54.7%) ( P <0.001). It is concluded that the risk of early resorption is increased in teeth that have additional damage or have contamination, or are kept in dry conditions for longer than 15 min.     

Evaluation of the topical effect of alendronate on the root surface of extracted and replanted teeth. Microscopic analysis on rats' teeth

Abstract –  The treatment of choice for tooth avulsion is replantation. The ideal replantation should be realized as quickly as possible, or at least, the avulsed tooth should be kept in an adequate solution to preserve the periodontal ligament attached to the root. If that is not possible, treatment of the radicular surface should be done in order to prevent radicular resorption. The purpose of this study was to test sodium alendronate as a substance for topical treatment of the radicular surface of avulsed teeth in an attempt to prevent the occurrence of dental resorptions. Fifty-four rat maxillary right central incisors were extracted and replanted. Group I – extra-alveolar dry period of 15 min, intracanal dressing with calcium hydroxide (CALEN^®, S.S. White, Artigos Dentários LTDA, Rio de Janeiro, Brazil) and replantation; Groups II and III – extra-alveolar dry periods of 30 and 60 min, respectively, immersion in 1% sodium hypochlorite for 30 min for removal of the periodontal ligament, washing in saline solution for 5 min, and treatment of the radicular surface with 3.2 mg/l sodium alendronate solution for 10 min. Intracanal dressing with calcium hydroxide and replantation followed. At 15, 60, and 90 days post-reimplantation, the animals were killed and the samples obtained and processed for microscopic analysis. The results indicated that sodium alendronate was able to reduce the incidence of radicular resorption, but not of dental ankylosis. No significant differences were observed regarding variations in the extra-alveolar periods among the groups.     

PCNA-expression of cementoblasts and fibroblasts on the root surface after extraoral rinsing for decontamination

Abstract  – Periodontal cells capable of proliferation were studied immunohistochemically on extracted human teeth after 2-min irrigation with saline or ozonized water and marking of Proliferating Cell Nuclear Antigen (PCNA). All specimens expressed PCNA. The labelling index (LI), i.e. the number of positive cells compared to the total number of cells, was 6.6% after irrigation with saline and 7.8% after irrigation with ozone. There was no difference in number and distribution of PCNA-positive cells from the coronal to the apical thirds of the roots. Irrigation with ozonized water showed higher labelling indices in comparison with saline, but this could not be statistically substantiated ( P  = 0.24). Ozonized water, not being isotonic, had no negative effect on periodontal cells remaining on the tooth surface after irrigation for 2 min.     

Effect of immediate calcium hydroxide treatment and permanent root-filling on periodontal healing in contaminated replanted teeth

Abstract – The effect of immediate permanent root-filling and immediate intracanal calcium hydroxide treatment on experimentally contaminated and necrotized periodontal membranes (PDM) in avulsed and subsequently replanted monkey teeth was studied. Almost the entire root surface in the non-endodontically treated control teeth were covered with inflammatory resorp-tion, A significant shift towards ankylosis not associated with root resorption (> 80% of the total root surface area) was noted following calcium hydroxide treatment. About two thirds of the root surfaces from the teeth with permanent root fillings showed surface resorptions or ankylosis preceded by root resorption. The root surface area which would have been covered by inffammatory resorption, unless endodontic treatment had been implemented, were instead predominantly covered by either surface resorption (permanent root filling) or ankylosis (calcium hydroxide treatment), Ankylosis compared with surface resorption may in the long term lead to progressive loss of root substance due to replacement resorption. It was concluded that calcium hydroxide may be an excellent initial intracanal treatment in teeth with healthy PDM, but care should be taken not to risk unnecessary development of ankylosis by prolonged treatment of teeth with compromised PDM.