BACKGROUND: Human periodontium contains different cell types that have various potential roles in hard and soft tissue regeneration. However, there is limited knowledge about how these diverse cell populations contribute to the regenerative process. In this study, we investigated the surface marker difference between different periodontal cells (alveolar osteoblasts [AOs], periodontal ligament fibroblasts [PDLFs], and gingival fibroblasts [GFs]) and their differentiation potential toward osteogenic and adipogenic phenotypes. METHODS: Periodontal cells (AOs, PDLFs, and GFs) from 14 subjects were isolated. The surface antigen expression pattern of cells was analyzed by cell flow cytometry, and the molecular and histologic characterizations under osteogenic and adipogenic inductions were monitored by reverse transcription-polymerase chain reaction, Western blot, and immunocytohistology. RESULTS: The cell phenotypes of AOs were verified by the high expressions of CD29 and CD49a, whereas PDLFs showed distinctively low levels of CD63 and CD73. Under adipogenic induction, limited AOs formed cube-shaped adipose-like cells, whereas PDLFs formed spindle-shaped adipose-like cells. All three cell types expressed baseline osteo-related genes. AOs demonstrated the highest osteogenic ability followed by PDLFs and GFs. CONCLUSIONS: Cells in alveolar bone and periodontal ligament contain osteogenic and adipogenic progenitors. These observations indicate a possible application for periodontium cells in hard or soft tissue regeneration.
This paper confines itself to the description of the profile of a general dentist while outlining where the boundary between specialist and generalist may lie. The profile must reflect the need to recognize that oral health is part of general health. The epidemiological trends and disease variation of a country should inform the profile of the dentist. A particular tension between the provision of oral healthcare in publicly funded and private services may result in dentists practicing dentistry in different ways. However, the curriculum should equip the practitioner for either scenario. A dentist should work to standards appropriate to the needs of the individual and the population within the country's legal and ethical framework. He/she should have communication skills appropriate to ascertain the patient's beliefs and values. A dentist should work within the principles of equity and diversity and have the knowledge and clinical competence for independent general practice, including knowledge of health promotion and prevention. He/she should participate in life-long learning, which should result in a reflective practitioner whose clinical skills reflect the current evidence base, scientific breakthroughs and needs of their patients. Within the 4-5 years of a dental degree it is not possible for a student to achieve proficiency in all areas of dentistry. He/she needs to have the ability to know their own limitations and to access appropriate specialist advice for their patients while taking responsibility for the oral healthcare they provide. The dentist has the role of leader of the oral health team and, in this capacity; he/she is responsible for diagnosis, treatment planning and the quality control of the oral treatment. The dental student on graduation must therefore understand the principles and techniques which enable the dentist to act in this role. He/she should have the abilities to communicate, delegate and collaborate both within the dental team and with other health professionals, to the benefit of the patient. The profile of a dentist should encompass the points raised but will also be based upon competency lists which are published by a variety of countries and organizations. It is important that these lists are dynamic so that they are able to change in light of new evidence and technologies.
The filling of bone defects in load-bearing areas requires scaffolds possessing physical properties that are in the range of those of the host bone. In this report, composite scaffolds comprising medical-grade polycaprolactone and tricalcium phosphate (mPCL-TCP) (80:20), which have been designed for load-bearing applications, are characterized and compared with mPCL scaffolds, using in vitro studies. The composite scaffolds exhibited improved hydrophilicity, compressive modulus and strength. Human alveolar osteoblasts (AOs) grown on the composite achieved higher seeding efficiencies and more uniform distribution when compared with mPCL preparations alone. AOs demonstrated better proliferation, denser multilayered cell-sheets and showed earlier expression of bone matrix-related proteins on the composite than on mPCL during 28 days in vitro culture. The calcium content in the media decreased in both scaffold/cell constructs. Alkaline phosphatase activity increased significantly in mPCL matrices after osteogenic induction but no distinct change was observed in the composite. Osteocalcin expression was down-regulated by induction in the composite but was up-regulated in mPCL at both RNA and protein level. Immuno-reactive signals for osteopontin and collagen type 1, in combination with mineral nodules were found to be stronger in mPCL-TCP scaffolds. We conclude that the composite scaffolds were more hydrophilic and had improved mechanical properties over mPCL scaffolds. Moreover, the primary AOs achieved better cell proliferation, and showed earlier and different matrix protein expression patterns on the composite scaffolds than on the mPCL scaffolds. (c) 2006 Society of Chemical Industry.
University Complutense of Madrid, Spain; Cardiff University, UK; Dutch Dental Association, Nieuwegein, Netherlands; University of Medicine and Dentistry of New Jersey, USA; University of Leeds, UK; Palacký University, Olomouc, Czech Republic; Howard University, Washington DC, USA; National University of Singapore; Dental Education Consultant, London UK; University of British Columbia, Vancouver, Canada; University of Detroit Mercy, Michigan USA.
Acidic fibroblast growth factor (aFGF) has been shown to facilitate wound healing by stimulating fibroblast proliferation and angiogenesis. It has also been reported to possess a powerful anti-apoptotic function This study compared the histological pulp responses to aFGF on collagen carrier and Ca(OH)(2) placed on the mechanically exposed dental pulp in monkeys at two observation periods. Thirty-six teeth with pulp exposures were distributed into three groups according to the capping agents used prior to application of the coronal seal: collagen-based matrix carrier (group 1), aFGF on the collagen-based matrix carrier (group 2) and aqueous calcium hydroxide [Ca(OH)(2)] paste (group 3). Specimens were harvested at 6 and 13 weeks postoperatively and prepared for hematoxylin and eosin, and Gram staining. Histological qualitative evaluation of pulp responses were performed under the light microscope following criteria modified from Cox et al. (17) and Hu et al. (18). Semi-quantitative analysis was also carried out using Kruskal-Wallis and Mann-Whitney U-tests. There was neither negligible inflammatory infiltrates with no bacteria present in the three groups at both timings, nor was there any significant difference in the soft tissue organization among the three groups at or between the 6- and 13-week observation periods. At 6 weeks, the hard tissue barrier produced by Ca(OH)(2) group (1.040 +/- 0.089) was significantly more superior than aFGF/collagen carrier group (1.930 +/- 0.825) (P = 0.030) as well as collagen carrier group (3.142 +/- 1.069, P = 0.018). At 13 weeks, both aFGF/collagen carrier group (1.214 +/- 0.485) and the collagen carrier group (1.457 +/- 0.814) produced significantly better hard tissue barrier (P = 0.040 and P = 0.017, respectively) than earlier timing. However, these two groups did not induce significantly improved hard tissue barrier compared to that produced by aqueous Ca(OH)(2) paste which stimulated matrix secretion in a polar tubular dentin-like pattern.
The optimal immediate management of traumatized teeth is known to be important for long-term success. One hundred and sixty-seven school dental therapists with General Certificate of Education 'Ordinary' (GCE 'O') level qualification were surveyed on their knowledge and experience on immediate management of dental trauma. The results showed only 41.2% felt comfortable with their present knowledge on the subject. A high proportion of the respondents (94.6%) indicated a need for more knowledge. All therapists concurred on the need to replant a permanent tooth and most (85.1%) agreed that this should be done within 30 min. More than half (54.8%) were not sure of the optimal storage medium for avulsed teeth. Their attitude towards acquiring knowledge in this aspect was good (80.5%) and all would take immediate action to settle appointments for trauma cases.
This study investigated the human alveolar osteoblasts (AOs) proliferation and extracellular matrix formation at seeding density of 0.05, 0.1, 0.2, 0.4, and 0.8 million (M) per 3x4x4 mm3 on medical grade polycaprolactone-tricalcium phosphate (mPCL-TCP) scaffolds designed for bone regeneration. Over 80-90% of the initial seeded cells were retained in the scaffolds after 24 h. AOs bridged over pores at density of 0.2M/scaffold and below, but formed cell balls at density of 0.4M/scaffold and above. At seeding density of 0.2M and below, cell proliferation increased with time having DNA content peaked to 1600 ng/scaffold at day 21 and 28, respectively, whereas at 0.4 and 0.8M, the corresponding DNA content decreased to 1600 ng in 28 days. At day 7, higher alkaline phosphatase (ALP) activity and higher osteocalcin (OCN) secretion were detected at 0.2M/scaffold and below. After 28 days, multilayered cell-sheet formation and collagen fibers were observed at all densities. ALP and OCN in matrix and mineral nodules were found mainly at the border of AOs-scaffold construct. These findings demonstrated that the density of 0.2M and below per 3 x 4 x 4 mm(3) scaffold resulted in better cell proliferation and extracellular matrix synthesis, potentially resulting in better mineralized tissue formation.
PURPOSE This paper reports on a 2-phase study of a novel membrane-scaffold graft construct, its ability to support periodontal ligament fibroblast (PDLF) and alveolar osteoblast (AO) growth in vitro, and its use for tissue engineering a PDL-AO interface in vivo. MATERIALS AND METHODS Human PDLFs were seeded onto perforated poly(epsilon-caprolactone) membranes (n=30) at 78,000 cells/cm2; human AOs were seeded on poly(epsilon-caprolactone) scaffolds (n=30) with fibrin glue at 625,000 cells/cm3. Cell attachment, morphology, viability, and metabolic activity were monitored for 3 weeks in vitro. Subsequently, cell-seeded membrane-scaffold constructs (experimental group, n=9) and nonseeded constructs (control group, n=4) assembled with fibrin glue were implanted subcutaneously into 7 athymic mice for 4 weeks. RESULTS PDLFs formed confluent layers on membranes, whereas AOs produced mineralized matrices within scaffolds upon osteoinduction in vitro. Well-vascularized tissue formation was observed after implantation. Integration at the membrane-scaffold interface was enhanced in the experimental group. Type I collagen, type III collagen, fibronectin, and vitronectin were found adjacent to membranes and within constructs. Bone sialoprotein expression and bone formation were undetectable. DISCUSSION Membrane perforation and scaffold porosity facilitated tissue integration and vascularization at the construct-recipient site. However, the interaction between PDLF and AO could have interfered with osteogenesis at the interface of soft and mineralizing tissues. CONCLUSIONS Both matrices supported PDLF and AO attachment and proliferation in vitro. The membrane-scaffold construct facilitated tissue growth and vascularization while providing strength and form in vivo.
Collagen modification of scaffolds has been reported to promote matrix mineralization as an effective way to increase osseointegration of implants. The aim of this study was to investigate in vitro proliferation and differentiation of human alveolar osteoblasts (AOs) on medical-grade polycaprolactone–tricalcium phosphate (mPCL-TCP 80:20) scaffolds after collagen modification (mPCL-TCP-c) for 28 days. Collagen modification significantly increased the scaffold’s protein adsorption ability, and improved the initial seeding efficiency and cell attachment at day 1, compared with non-collagen-modified scaffolds. However, the total DNA content of both groups reached similar levels with no significant difference at 28 days’ culture. AOs were observed to spread along the collagen fibres and form extensive collagenous fibres with mineral nodules embedded, while multilayered cell sheets were formed in mPCL-TCP scaffolds. During culture, alkaline phosphatase (ALP) activity increased three- to five-fold in both groups, and collagen modification did not significantly affect either the metabolic rate or ALP activity kinetics of AOs. During osteogenic differentiation, similar gene expression of collagen type-I, osterix, osteopontin, and osteocalcin were detected in both groups. The mPCL-TCP group showed better organized mineralized tissue, but the mPCL-TCP-c showed more scattered and unorganized tissue. These results indicate that collagen modification improved the scaffold’s protein adsorption ability and encouraged initial cell attachment and distribution, but promoted fibrous-like tissue formation rather than mineralized tissue.
Traumatic dental injuries result in tissue damage and risk of infection. Experimental studies have shown various avenues for bacterial invasion following trauma: enamel infractions, dentinal tubules, exposed pulps, damaged periodontal ligament (PDL) and exposed alveolar bone. Hematogenous seeding of bacteria (anachoresis) may also occur during pulpal revascularization after trauma. The implication of these routes of entry differs according to the type of traumatic dental injury. It is known that bacterial colonization in a wound may protract or even arrest healing. Hence, it might be of interest to examine the possibility of protecting the healing events by the use of antibiotics after dental and maxillofacial trauma. A survey of the literature revealed a series of studies using an extraction/replantation model in monkeys and dogs. In periodontal ligament healing, these studies showed that systemically administered antibiotics (penicillin, streptomycin, amoxicillin and tetracycline) or topically applied antibiotics either on the root surface or in the root canal in general had the effect of preventing or reducing the extent of infection‐related resorption. With respect to pulpal healing, systemically administered antibiotics had no effect upon pulp healing whereas topically administered tetracycline (5 min storage in a tetracycline solution or the use of tetracycline powder) doubled the chance of pulp revascularization. To date, there has been only one non‐randomized clinical replantation study which showed that systemically applied penicillin did not reduce root resorption or the chance of pulp revascularization. In experimental studies, the topical use of tetracycline appeared to significantly improve the chance of revascularization of the pulp after replantation. In other dental trauma types, only a few clinical studies were available concerning the role of antibiotics and none of them were randomized. No positive effect of antibiotics has been reported on pulpal healing in cases of luxation injury or root fracture. Regarding PDL healing, a possible negative effect of antibiotics was indicated for lateral luxations; however, confounding factors might exist. In the case of mandibular fractures with communication to the oral cavity, five randomized studies were found, all indicating that antibiotics significantly reduced the risk of fracture line infection. Randomized clinical studies on the effect of systemic and topical use of antibiotics for traumatic dental injuries are very much needed.
AIM To evaluate the in vitro antimicrobial effect of chlorhexidine-impregnated gutta percha points, Roeko activ point (Roeko, Langenau, Germany) on Enterococcus faecalis. METHODOLOGY Human maxillary premolar roots were prepared with.04 rotary ProFile instruments to a master apical file size 40, autoclave-sterilized and then infected with E. faecalis (ATCC 29212) for 3 weeks. Baseline controls were carried out verifying negligible effects of plain gutta percha cones on E. faecalis. Subsequent to intracanal placement of calcium hydroxide, 'activ points' or saline (positive control) and the 2-week incubation in 54 root specimens, dentine sampling at depths of 100 and 250 micro m was carried out using.04 rotary ProFile instruments at sizes 60 and 90 to assess the quantity of bacteria present. Inactivating agents were used prior to sampling and the colony-forming units (CFU) of E. faecalis were then plate-counted after culturing. Statistical analysis was completed using the paired t-test. RESULTS In comparison to the positive control, treatment with calcium hydroxide (P = 0.000 and 0.000) or activ points (P = 0.000 and 0.002) produced significantly lower colony counts of E. faecalis at dentine depths of 100 and 250 micro m, respectively. Calcium hydroxide (2.10 x 102 CFU mL-1) was significantly more effective than activ points (1.58 x 103 CFU mL-1) at 100 micro m (P = 0.013), but not at 250 micro m (P = 0.353). Neither of these two medications was able to eliminate E. faecalis completely. CONCLUSIONS Chlorhexidine-impregnated activ points did not possess an in vitro inhibitory activity strong enough to eliminate E. faecalis completely from infected dentinal tubules.
BACKGROUNDBasic fibroblast growth factor (bFGF; FGF-2) has been reported to facilitate wound healing and periodontal regeneration in experimental alveolar bone defects. The purpose of this study was to evaluate histologically the effect of topically applied bFGF with or without fibrin glue on delayed-replanted monkey teeth prone to replacement resorption.METHODSForty-five roots from five monkeys were endodontically treated aseptically and then extracted as atraumatically as possible. Ten negative control roots were replanted immediately, while 12 positive control roots were allowed to bench dry for 1 hour prior to replantation, both without further treatment. Roots in the two experimental groups were bench dried for 1 hour, rinsed with saline, and then replanted into sockets filled with bFGF with (11 roots) or without (12 roots) fibrin glue. After 12 weeks, histological sections were prepared and evaluated according to morphometric analysis as complete healing or unfavorable healing composed of inflammatory resorption and replacement resorption.RESULTSKruskal-Wallis and Mann-Whitney U tests showed teeth in the negative control group to have significantly higher complete healing (98.88% +/- 2.30%) and significantly lower unfavorable healing (1.12% +/- 2.30%) than the positive control group and the experimental groups. bFGF/fibrin glue group showed higher occurrence of complete healing (39.06% +/- 41.62%) compared to the bFGF group (25.28% +/- 28.85%) and the positive control group (16.58% +/- 19.60%), although the differences were not significant. Comparing the complete and unfavorable healing, there was no significant difference in the bFGF/fibrin glue group (P = 0.47), but the differences were significant in the other groups (P < 0.05).CONCLUSIONTopical application of bFGF with fibrin glue showed an insignificantly higher occurrence of complete healing in delayed-replanted monkey teeth.
Aim To evaluate the in vitro antimicrobial effect of chlorhexidine-impregnated gutta percha points, Roeko activ point (Roeko, Langenau, Germany) on Enterococcus faecalis . Methodology Human maxillary premolar roots were prepared with .04 rotary ProFile instruments to a master apical file size 40, autoclave-sterilized and then infected with E. faecalis (ATCC 29212) for 3 weeks. Baseline controls were carried out verifying negligible effects of plain gutta percha cones on E. faecalis . Subsequent to intracanal placement of calcium hydroxide, ‘activ points’ or saline (positive control) and the 2-week incubation in 54 root specimens, dentine sampling at depths of 100 and 250 µm was carried out using .04 rotary ProFile instruments at sizes 60 and 90 to assess the quantity of bacteria present. Inactivating agents were used prior to sampling and the colony-forming units (CFU) of E. faecalis were then plate-counted after culturing. Statistical analysis was completed using the paired t -test. Results In comparison to the positive control, treatment with calcium hydroxide ( P = 0.000 and 0.000) or activ points ( P = 0.000 and 0.002) produced significantly lower colony counts of E. faecalis at dentine depths of 100 and 250 µm, respectively. Calcium hydroxide (2.10 × 10 2 CFU mL −1 ) was significantly more effective than activ points (1.58 × 10 3 CFU mL −1 ) at 100 µm ( P = 0.013), but not at 250 µm ( P = 0.353). Neither of these two medications was able to eliminate E. faecalis completely. Conclusions Chlorhexidine-impregnated activ points did not possess an in vitro inhibitory activity strong enough to eliminate E. faecalis completely from infected dentinal tubules.
OBJECTIVE:We sought to histologically evaluate the effect of Emdogain gel on periodontal healing in monkeys' teeth undergoing delayed replantation. Study design Mature monkey teeth simulating avulsion were endodontically treated before extraction. Negative control teeth (group N = 10 roots) underwent immediate replantation, whereas the rest were bench-dried for 1 hour and treated in one of the following ways before replantation: the positive control teeth (group P = 12 roots) had no further treatment; group C teeth (4 roots) had the periodontal ligament removed; group D teeth (10 roots) were treated with Emdogain gel; group E teeth (6 roots) had the periodontal ligament removed before the application of Emdogain gel; and group F teeth (7 roots) had the periodontal ligament removed, the root surface conditioned, and Emdogain gel applied. Periodontal healing was evaluated after 16 weeks by undertaking histomorphometric analysis.RESULTS:The Kruskal-Wallis and Mann-Whitney U tests revealed that group N teeth had a statistically higher occurrence of complete healing than did all other groups, whereas group P was not significantly different in any of the healing categories from D, E, and F, the groups in which Emdogain gel was used. Group C teeth had a significantly higher occurrence of replacement root resorption than did the teeth in groups P and F-but were not significantly different from teeth in groups D and E.CONCLUSION:Emdogain gel did not appear to significantly reduce replacement resorption in monkeys' teeth that had undergone delayed replantation.
AIMTo evaluate the effectiveness of Glyde File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation.METHODOLOGYThirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: Glyde File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (x40 and x100) and scanning electron microscope (x1000 and x3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance (anova) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively.RESULTSThe canals treated with EDTA and Glyde File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant.CONCLUSIONSUsed in conjunction with NaOCl irrigation, Glyde File Prep was effective in removing smear layer produced during root canal instrumentation.
The in vitro pH changes in root dentin over a period of 2 weeks was investigated in 48 extracted bicuspids after intracanal placement of either Roeko Calcium Hydroxide Plus Points, aqueous calcium hydroxide paste, or gutta-percha points (control group) after root canal preparation. Microelectrodes were placed in outer and inner root dentin at cervical, middle, and apical thirds of the root to measure the pH at 1 h, 2 h, 3 h, 1 day, 3 days, 7 days, and 14 days. Roeko Calcium Hydroxide Plus Points reached a peak inner dentine pH of 11.67 and a peak outer dentine pH of 10.82 at 3 h. In addition, Roeko Calcium Hydroxide Plus Points maintained an outer dentine pH above 9.5 for approximately 2 days, whereas the aqueous calcium hydroxide paste did not reach this pH. However, the alkalinity in dentin with Roeko Calcium Hydroxide Plus Points was maintained for 7 days only, whereas aqueous calcium hydroxide paste maintained an alkaline environment throughout the 2-week period.
Aim To evaluate the effectiveness of Glyde™ File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation. Methodology Thirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: Glyde™ File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (×40 and ×100) and scanning electron microscope (×1000 and ×3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance ( anova ) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively. Results The canals treated with EDTA and Glyde™ File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant. Conclusions Used in conjunction with NaOCl irrigation, Glyde™ File Prep was effective in removing smear layer produced during root canal instrumentation.
Tetracycline has been reported to possess antiresorptive properties in addition to antimicrobial actions. Systemic administration of tetracycline showed variable results in the control of replacement resorption after replantation with good results in half of the cases, and almost no healing in the rest. The purpose of this study was to evaluate histologically the effect of topically applied minocycline on replacement resorption of replanted monkeys' teeth. Thirty-two roots from seven monkeys were endodontically treated aseptically to prevent inflammatory resorption of pulpal origin, a common sequela after avulsion injury. Teeth were then extracted as atraumatically as possible. Teeth in the negative control group (10 roots) were replanted almost immediately, while teeth in the positive control group (12 roots) were allowed to bench-dry for 1 h prior to replantation, both without further treatment. Teeth in the experimental group (10 roots) were bench-dried for 1 h, rinsed with saline, and then immersed in 1 ml of 50 mg ml(-1) minocycline hydrochloride for 5 min before replantation. No splinting was used. After 12 weeks, the animals were sacrificed and histological sections were prepared and evaluated according to a morphometric analysis modified from that described by Andreasen (1987) as complete healing, inflammatory resorption, and replacement resorption. Kruskal-Wallis test showed significant differences among the three groups in all the three healing categories. Further analysis with Mann-Whitney U-test showed teeth in the negative control group to have significantly higher complete healing and significant lower unfavorable healing, comprising of replacement resorption and inflammatory root resorption than the positive control group and the minocycline group. Topical application of minocycline to the root surface appeared to result in slightly higher occurrence of complete healing (32.46%) compared to the delayed replantation group with no minocycline treatment (positive control) (16.58%), but the difference was not statistically significant (P = 0.09).