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ABSTRACT: The biomechanical character of the periodontal ligament (PDL) is crucial in its response to functional and orthodontic forces. Collagen has been the primary subject of investigations in this field. Several studies, however, indicate that oxytalan fibres, which belong to the elastic fibre family, also contribute to the biomechanical character and behaviour of the PDL. In order to elucidate this, we have evaluated the available literature on the oxytalan fibre network within the PDL and supra-alveolar tissues with respect to development, morphology and distribution, and response to mechanical stimulation. To this end, we have combined the classical histological studies with more recent in vitro studies. Oxytalan fibres develop simultaneously with the root and the vascular system within the PDL. A close association between oxytalan fibres and the vascular system also remains later in life, suggesting a role in vascular support. Mechanical loading of the PDL, through orthodontic force application, appears to induce an increase in the number, size, and length of oxytalan fibres. In line with this, in vitro stretching of PDL fibroblasts (PDLFs) results in an increased production of fibrillin, a major structural component of the microfibrils that make up oxytalan fibres. The available data suggest a mechanical function for oxytalan, but to date experimental data are limited. Further research is required to clarify their exact mechanical function and possible role in orthodontic tooth movement.
Archives of oral biology 07/2012; 57(8):1003-11. · 1.65 Impact Factor
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ABSTRACT: To compare two often used rat models for experimental tooth movement, namely the elastic band, and the coil spring model. They were compared with a silk-ligature-induced periodontitis model.
Thirty six, 6-weeks-old rats were used. In a split mouth design four experimental conditions were allocated by permutation: (1) insertion of an orthodontic elastic band between the maxillary first and the second molar, (2) placement of a silk ligature around the cervix of the upper second molar, (3) a 10cN NiTi coil spring for mesial movement of the three maxillary molars as one block, and (4) Control. After 1, 3, and 5 days, rats were killed and immunohistochemical staining for ED1, cathepsin K, and MMP9 was performed.
A time-dependent increase in the inflammatory infiltration of the interdental papilla was found in the elastic band and the ligature model, but not in the spring model. The disruption of the epithelium of the interdental papilla and the transseptal fibers was less severe in the spring group than in the other two experimental groups. All three experimental groups showed a time-dependent resorption of the interdental bony septum. However, this started faster and was more severe in the elastic band and the ligature than in the spring group. The numbers of cathepsin K+ and MMP9+ cells were higher in the elastic band and the ligature group than in the spring group.
Elastic bands yield similar periodontal effects as ligatures. The spring model is to be preferred for experimental tooth movement studies.
Archives of oral biology 10/2010; 56(2):159-67. · 1.65 Impact Factor
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ABSTRACT: Our aim was to compare the dentoalveolar development in beagle dogs after palatal repair according to the Von Langenbeck technique with and without implantation of a dermal substitute.
Nineteen beagles (age, 12 weeks) were assigned to 2 experimental groups and an untreated control group. Palatal surgery was performed with the Von Langenbeck technique in the 2 experimental groups. The dermal substitute Integra (Plainsboro, NJ, USA) was implanted in 1 experimental group, and the other served as sham group. Dental casts were made before surgery and at several times in all groups to measure dentoalveolar development. Transversal distances, arch depth, tipping, and rotation were determined. Histologic evaluations were performed at 3, 7, and 15 weeks after surgery. The degrees of reepithelialization and tissue organization were evaluated microscopically.
All wounds healed without complications. Scar tissue attached to the bone was found in both experimental groups. Deposition of bone in the Integra occurred after implantation, indicating its osteoconductivity. Transversal dentoalveolar development was similar in both experimental groups, but it was significantly less than in the control group.
Implantation of Integra after the Von Langenbeck procedure for palatal repair does not improve dentoalveolar development.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 07/2010; 138(1):58-66. · 1.33 Impact Factor
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ABSTRACT: Osteoclasts are derived from macrophage-lineage precursors. ED1 is an antibody that can recognize this lineage of cells. Matrix metalloproteinase 9 (MMP9) is essential for the migration of osteoclasts and their precursors during osteoclastogenesis. The aim of this research was to investigate differentiation and recruitment of osteoclasts during the early phase of experimental tooth movement in rats. The upper three molars of Wistar rats at one side were moved mesially, using Ni-Ti coil springs of 10 cN, for 6, 12, 24, 36, 48, 72, 96, and 120 h. The contralateral sides served as controls. Immunohistochemical staining using ED1 and MMP9 antibodies was performed. ED1(+) and MMP9(+) mononuclear and multinuclear cells were counted and statistically analysed. After force application, the number of ED1(+)/MMP9(+) multinuclear cells first increased in the bone marrow. At compressed areas, the number of ED1(+) mononuclear cells decreased; this was followed by an increase in the number of ED1(+/)MMP9(+) mononuclear and multinuclear cells. At tension areas, the number of ED1(+)/MMP9(+) multinuclear cells decreased while the number of ED1(+) mononuclear cells remained stable. It was concluded that force application induces osteoclast differentiation within the bone marrow. These osteoclasts probably migrate subsequently into the compressed PDL. Pre-existing osteoclasts disappear at the tension areas while the number of mononuclear macrophage-lineage cells remains stable.
European Journal Of Oral Sciences 03/2009; 117(1):43-50. · 1.88 Impact Factor
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ABSTRACT: Recently, several reviews have been published on the effects of medications on bone physiology and the clinical side effects in orthodontics. However, the effects of medications on the rate of orthodontic tooth movement have not been evaluated.
A systematic literature review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed by using PubMed (1953-Oct 2007), Web of Science, and Biosis, complemented by a hand search.
Forty-nine articles were included in the review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement, and medication regimens. Therapeutic administration of eicosanoids resulted in increased tooth movement, whereas their blocking led to a decrease. Nonsteroidal anti-inflammatory drugs (NSAIDs) decreased tooth movement, but non-NSAID analgesics, such as paracetamol (acetaminophen), had no effect. Corticosteroid hormones, parathyroid hormone, and thyroxin have all been shown to increase tooth movement. Estrogens probably reduce tooth movement, although no direct evidence is available. Vitamin D3 stimulates tooth movement, and dietary calcium seemed to reduce it. Bisphosphonates had a strong inhibitory effect.
Medications might have an important influence on the rate of tooth movement, and information on their consumption is essential to adequately discuss treatment planning with patients.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 02/2009; 135(1):16-26. · 1.33 Impact Factor
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Journal of cranio-maxillo-facial surgery: official publication of the European Association for Cranio-Maxillo-Facial Surgery 01/2009; 37(3):140-4. · 1.25 Impact Factor
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ABSTRACT: Introduction: Recently, several reviews have been published on the effects of medications on bone physiology and the clinical side effects in orthodontics. However, the effects of medications on the rate of orthodontic tooth movement have not been evaluated. Methods: A systematic literature review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed by using PubMed (1953-Oct 2007), Web of Science, and Biosis, complemented by a hand search. Results: Forty-nine articles were included in the review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement, and medication regimens. Therapeutic administration of eicosanoids resulted in increased tooth movement, whereas their blocking led to a decrease. Nonsteroidal anti-inflammatory drugs (NSAIDs) decreased tooth movement, but non-NSAID analgesics, such as paracetamol (acetaminophen), had no effect. Corticosteroid hormones, parathyroid hormone, and thyroxin have all been shown to increase tooth movement. Estrogens probably reduce tooth movement, although no direct evidence is available. Vitamin D3 stimulates tooth movement, and dietary calcium seemed to reduce it. Bisphosphonates had a strong inhibitory effect. Conclusions: Medications might have an important influence on the rate of tooth movement, and information on their consumption is essential to adequately discuss treatment planning with patients. (Am J Orthod Dentofacial Orthop 2009;135: 16-26) R ecently, several reviews have been published about the biologic processes related to orth-odontic tooth movement (OTM). 1-4 These re-views describe similar reactions of periodontal cells and extracellular matrices to orthodontic force applica-tion. Briefly, the principal trigger for OTM is probably strain of the periodontal ligament cells, bone-related cells, and the extracellular matrix. 3 This strain leads to changes in gene expression in the cells by interactions between the cells and the extracellular matrix, whereby integrins play an important role. 2 Various cell-signaling pathways are activated, which ultimately lead to stim-ulation of periodontal ligament turnover, and localized bone resorption and bone deposition. 2-4 In addition, recent reviews by several authors have been published on the effects of systemic or local application of medications and the intake of dietary supplements, such as vitamins and minerals, during OTM. 5-7 In most cases, these reviews distinguish 2 categories of effects: those related to general bone physiology in terms of bone density, bone mineraliza-tion, bone turnover rate, and osteoclast differentiation; and clinical side effects induced by medications, such as gingival hyperplasia, xerostomia, and external root resorption. 5-7 Most reviews, however, did not report experimental data on the effects of medications or dietary supplements on the rate of OTM. 7-10 Nonetheless, such information is important for clinicians in communications with patients, because many patients use prescription and over-the-counter medications, as well as dietary supplements daily. Consequently, these substances can affect both the rate of OTM and the expected duration of treatment. 6,7,11 Therefore, we performed a systematic literature review based on experimental data on the sequelae of pharmaceutical interventions and the use of dietary supplements on the rate of OTM. Unfortunately, only a few human clinical trials have been published. 12-14 As a result, this review focuses mainly on well-controlled animal studies. Our review is organized around several regulatory systems of which disturbances might lead to pathologic
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ABSTRACT: To investigate the age-dependent morphology of the periodontal ligament (PDL) tissue and changes in its surface area (SA) during force application provided with a standardized orthodontic setup for a period of 12 weeks in young and adult rats.
Two groups of 30 rats, age 6 weeks and 9 to 12 months, were used. Orthodontic appliances were placed to move the maxillary molars mesially with the contralateral sides used as controls. At 1, 2, 4, 8, and 12 weeks, groups of animals were killed. The PDL SA and the PDL SA ratio between pressure and tension regions were determined.
An age-related decrease in the PDL SA was noted at control sides. Significant changes during the experimental period occurred only at experimental sides: The PDL SA was smaller at pressure than at tension regions only at week 1 in young rats; in adult rats, the difference between the two regions was significant at week 8. These changes were confirmed by the morphologic disorganization of the PDL and alterations in the PDL SA ratio.
During force application, the PDL at the pressure regions became disorganized and subsequently was reorganized, as is shown by the histologic changes and SA of the PDL over time. This process occurred earlier and was more prominent in young rats; it occurred later and was more prolonged in adult animals.
The Angle Orthodontist 12/2008; 78(6):1000-5. · 1.21 Impact Factor
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ABSTRACT: In orthodontics, facial esthetics is assumed to be related to golden proportions apparent in the ideal human face. The aim of the study was to analyze the putative relationship between facial esthetics and golden proportions in white adolescents.
Seventy-six adult laypeople evaluated sets of photographs of 64 adolescents on a visual analog scale (VAS) from 0 to 100. The facial esthetic value of each subject was calculated as a mean VAS score. Three observers recorded the position of 13 facial landmarks included in 19 putative golden proportions, based on the golden proportions as defined by Ricketts. The proportions and each proportion's deviation from the golden target (1.618) were calculated. This deviation was then related to the VAS scores.
Only 4 of the 19 proportions had a significant negative correlation with the VAS scores, indicating that beautiful faces showed less deviation from the golden standard than less beautiful faces. Together, these variables explained only 16% of the variance.
Few golden proportions have a significant relationship with facial esthetics in adolescents. The explained variance of these variables is too small to be of clinical importance.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 11/2008; 134(4):480-3. · 1.33 Impact Factor
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ABSTRACT: The aim of the study was to evaluate the influence of the characteristics of panel members, the effects of gender and Angle Class of adolescent patients on their change in facial aesthetics following orthodontic treatment, and to assess the optimal panel size for epidemiological studies on changes in facial aesthetics after orthodontic treatment. A panel of 74 adult laymen (35 males and 39 females) and a panel of 87 orthodontists (37 males and 50 females) evaluated sets of three post-treatment standardized photographs (one frontal, one three-quarter smiling, and one lateral) of 64 adolescent orthodontic patients in relation to the pre-treatment sets of the same patient on a five-point scale. The main effects of professional background, age, gender, and geographic region of the panel members on the aesthetic scores, as well as their first order interactions were evaluated by multilevel models. Professional background, age, gender, and geographical region of panel members have an influence on the evaluation of the change of facial aesthetics following orthodontic treatment. The effect of gender and Angle Class of the patients on the scores was evaluated by two-way analysis of variance. There was no difference in the mean scores for boys and girls. Improvement of facial aesthetics by orthodontic treatment was significant for Class I, Class II division 1, and Class II division 2 patients, but not for Class III patients. Based on the intraclass correlation coefficient, a panel of nine randomly selected orthodontists, a panel of 14 randomly selected laymen, or a mixed panel of 13 individuals is sufficient to obtain reliable results in the aesthetic evaluation of adolescent faces, using photographs and a five-point scale.
The European Journal of Orthodontics 05/2008; 30(2):141-6. · 0.89 Impact Factor
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ABSTRACT: Age effects on orthodontically induced periodontal vascular reactions have not been studied. The aim of the present study was to test the hypothesis that prolonged tooth movement induces age-related increases in periodontal vascularity.
A standardized orthodontic appliance was placed in 2 groups of 30 rats aged 6 weeks and 9 to 12 months. At 1, 2, 4, 8, and 12 weeks, animals were killed. Blood vessels (BV) were identified based on their morphology and by immunohistochemical staining for alpha-smooth muscle actin. At each study region, surface areas (SA) of the periodontal ligament space and each BV were measured; BV mean SA, BV relative SA (the summed BV SA as a percentage of the periodontal ligament SA), and BV numbers were calculated.
Pressure and tension regions showed similar vascular changes. Young rats had lower BV relative SA and BV mean SA in the early phase of force application (< 4 weeks); this increased in the late phase, reaching the same level as adult rats. In the late phase (4-12 weeks), young rats had increases of both small- and large-sized BV that did not affect the BV mean SA; adult rats had an increase of small-sized BV only; this resulted in decreased BV mean SA.
The hypothesis was confirmed that prolonged tooth movement increases periodontal vascularity, which is age related. These results suggest that clinicians should consider age-related difference in tissue reactions during orthodontic tooth movement.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 05/2008; 133(5):752-7. · 1.33 Impact Factor
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ABSTRACT: To investigate the effect of age on root resorption and distribution along different parts of the root during prolonged light force application.
Orthodontic appliances were placed in two groups of 30 rats (one group 6 weeks old, the other 9-12 months old), with contralateral sides as controls. Groups of animals were killed at 1, 2, 4, 8, and 12 weeks. At the study site, incidence was counted as either 1 (with resorption) or 0 (without); severity was measured as the summed length of all resorption lacunae as a percentage of study total root length.
Young and adult rats had the same incidence of root resorption in the early phase (<4 weeks), and both increased in the late phase (4-12 weeks) to the same level. Severity of resorption increased with prolonged tooth movement only in adult rats. However, there was no age-related difference in either the early or the late phase. In both groups, the middle part of the root had the highest incidence of resorption; the most severe resorption occurred exclusively at this part.
Orthodontic intervention even with light forces increased both the incidence and severity of root resorption, the more so in the middle part of the root. Adult rats had increased incidence and severity with prolonged tooth movement.
Acta odontologica Scandinavica 05/2008; 66(2):93-8. · 1.41 Impact Factor
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ABSTRACT: Many guidelines, norms, and ideal ratios and angles for attractive faces have been proposed in the literature. The aim of this study was to test the hypothesis that facial attractiveness in adolescents is related to ideal angles and ratios, as indicated in the literature.
Seventy-six laypeople viewed sets of photographs of 64 adolescents and rated them on a visual analog scale (VAS) from 0 to 100. The facial esthetic value of each subject was calculated as a mean VAS score. Three observers recorded the positions of 61 landmarks, and 45 were found to have acceptable reproducibility. Based on these 45 landmarks, 27 ideal ratios on frontal photographs and 26 ideal angles on lateral photographs were identified in the literature. These ratios and angles were calculated on each photograph, and their deviation from the ideal targets in the literature were determined. Each deviation was related to the VAS score.
Two ratios and 3 angles had a significant negative correlation with the VAS scores, indicating that beautiful faces have less deviation from the ideal target than less beautiful faces. Together, these variables explained 28.7% of the variance.
Few "ideal" ratios and angles have a significant relationship with facial esthetics in adolescents.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 03/2008; 133(2):188.e1-8. · 1.33 Impact Factor
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ABSTRACT: Tissue shortage complicates the surgery of cleft palate (CP) anomalies. The healing of defects on the palate impairs growth of the dento-maxillary complex due to scar tissue formation. Implantation of grafts into the wound area might reduce this adverse effect of surgery. The aim of this study was to evaluate a cultured autologous mucosal substitute, which can be used as a graft material. Two different types of cultured mucosal substitutes composed of skin-derived substrates (unprocessed dermis and AlloDerm) and autologous oral keratinocytes were implanted in palatal wounds in six beagle dogs (1-1.5 years of age). The cultured substitutes were compared with a sham and a control group. The animals were sacrificed in pairs 1, 3, and 12 weeks after surgery. Epithelial regeneration, inflammatory response (leucocyte protein L1), ingrowth of (myo-) fibroblasts, collagen type III, and formation of a basal membrane (JM 403) were evaluated. The results demonstrated that all cultured substitutes possessed a multilayered epithelium, closely resembling normal palatal epithelium. After implantation, however, the epithelium was lost and an inflammatory response was observed in the first week. After 3 and 12 weeks, the implanted substitutes had completely disappeared and epithelial migration occurred from the wound margins. It is possible to culture an autologous epithelium on a skin-derived substrate and implant it as an oral mucosal substitute in palatal wounds. However, these substitutes do not improve the healing of palatal wounds. It is suggested that the revascularization of the wound area is too slow to allow survival and integration of the substitutes.
The European Journal of Orthodontics 03/2008; 30(1):1-9. · 0.89 Impact Factor
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ABSTRACT: The aim of this study was to investigate tooth movement characteristics in relation to root resorption in young and adult rats. Two groups of 30 rats each (aged 6 wk and 9-12 months, respectively) were used. Standardized orthodontic appliances were placed to move the maxillary molars mesially. Animals were killed 1, 2, 4, 8, and 12 wk after the beginning of the experiment and their jaws were processed for histomorphometric analysis. In parasagittal sections of 'pressure zones' the extent of root resorption was measured and expressed as percentage of total root length. Whereas a negative correlation was found between the velocity of tooth movement and the extent of root resorption, a positive correlation was noted between the amount/duration of tooth movement and root resorption, but only in adult rats. The duration of tooth movement showed the highest correlation coefficient and the smallest 95% confidence interval. In younger animals, correlations were weak, and other factors are likely to be involved in the individual susceptibility to root resorption.
European Journal Of Oral Sciences 01/2008; 115(6):449-53. · 1.88 Impact Factor
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ABSTRACT: Tissue shortage complicates surgery of cleft lip and palate. The healing of defects on the palate impairs growth of the dentoalveolar complex because of scar tissue formation. Implantation of a matrix into the wound might overcome this adverse effect. Integra with and without a silicone top layer was implanted into standardized full-thickness wounds (Ø 6 mm) in the palatal mucoperiosteum in beagle dogs. In some wounds, the silicone layer was removed after 14 days. Control wounds did not have an implant. At 2 and 4 weeks post-surgery, the wounds were assessed for epithelialization, inflammation (hematoxylin and eosin, leucocyte protein L1), number of myofibroblasts (alpha smooth muscle actin), and general histological characteristics. Wounds filled with Integra without the silicone layer showed fewer myofibroblasts and inflammatory cells than the sham wounds. Collagen fibers were more randomly orientated in these wounds than in the sham group. Wound closure was found to be retarded, and many inflammatory cells were present when Integra with silicone was implanted. The silicone layer was lost within 4 weeks in these wounds. We conclude that, in the moist oral environment, the silicone of Integra is not required. Re-epithelialization and tissue integration proceed more favorably without it. Further research in the dentoalveolar development with Integra will be conducted in a simulated cleft palate repair in the dog model.
Tissue Engineering 12/2007; 13(11):2689-98. · 4.02 Impact Factor
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ABSTRACT: The margin of a palatal cleft is a unique anatomical site since the palatal mucosa is continuous with the nasal or nasopharyngeal mucosa. The aim of this study was to compare the expression patterns of cytokeratins and basal membrane components of the mucosa in the area of the cleft.
Biopsies from the mucosa of the hard palate and from the cleft margin in the soft palate were obtained from five patients during the primary surgical closure of the cleft. The tissues were processed for haematoxylin-eosin staining and for immunohistochemistry. Antibodies against the cytokeratins (CK) 4, 7, 8, 10, 13, 16 and 18, and the basal membrane components heparan sulphate (HS) and collagen type IV (CIV) were used for immunostaining.
The nasopharyngeal epithelium was thinner than the epithelium of the soft palatal mucosa, and showed less interpapillary ridges. The nasopharyngeal epithelium was stratified but expressed the keratins of a simple epithelium (CK 7, 8 and 18). The expression pattern abruptly changed into that of a typical non-keratinized stratified epithelium (CK 4, 13) at the transition to the soft palatal epithelium. The epithelium of the hard palate was a fully differentiated, keratinized and stratified epithelium (CK 10, 16). The basal membrane was thinner in the nasopharyngeal epithelium, which might be related to the presence of abundant inflammatory cells.
The area around the palatal cleft showed three different types of epithelium. There was an abrupt transition in phenotype of the epithelium from the oral side to the nasopharyngeal side.
Archives of Oral Biology 08/2006; 51(7):573-80. · 1.60 Impact Factor
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ABSTRACT: Orthodontic tooth movement starts slower in adults than in juveniles, but the rate of tooth movement in later phases is the same in both age groups. The hypotheses to be tested are that these phenomena are related to slower osteoclast recruitment in adults than in juveniles, but that in later phases the osteoclast numbers are the same in both age groups.
Standardized orthodontic tooth movement was performed in two groups of 30 rats, aged 6 weeks and 9-12 months, respectively. All maxillary molars at one side were together moved mesially by a continuous force of 10 cN. The other side served as a control. After 1, 2, 4, 8 and 12 weeks, groups of animals were killed. After ED1 staining osteoclast numbers at the mesial and distal sides of selected roots were counted.
At the compression sides osteoclast numbers increased in both age groups. In young rats, a maximum was reached at 2 weeks, in adults at 4 weeks. In later phases of tooth movement, the number of osteoclasts in the adults was approximately twice as high as in the juveniles, while the rate of tooth movement was the same. A positive correlation between the rate of tooth movement and osteoclast numbers was found only in young rats.
Orthodontic forces induce faster osteoclast recruitment in young than in adult rats and more osteoclasts are needed to achieve a certain rate of tooth movement in adult than in young rats.
Archives of Oral Biology 01/2006; 50(12):1032-9. · 1.60 Impact Factor
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ABSTRACT: The concern that a sagittal split osteotomy of the mandibular ramus could compromise the subchondral vascularization and especially the venous outflow in the condylar area, which in turn could influence the structure of the condylar cartilage, prompted this preliminary study on goats.
A sagittal split osteotomy was performed in the mandibular ramus at 1 side in each of 6 young adult goats. The contralateral side served as control. The animals were killed after different postoperative periods, ranging from 1 to 15 days. Histomorphometric analyses were performed after perfusion of the vascular system with India ink.
Based on the observed cartilage thickening, the sagittal split osteotomy may influence the condylar cartilage in the first days postoperatively through a disturbance of the vascular supply.
Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 09/2005; 100(2):138-45; discussion 146. · 1.50 Impact Factor
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ABSTRACT: Wound healing after cleft palate surgery is often associated with impairment of maxillary growth and dento-alveolar development. Wound contraction and scar tissue formation contribute strongly to these effects. In vitro studies have revealed that fibroblasts isolated during different phases of palatal wound healing show phenotypical differences. They change from a quiescent to an activated state and then partly back to a quiescent state. In this study, we evaluated the existence of fibroblast phenotypes at several time-points during palatal wound healing in the rat. Based on cytoskeletal changes (alpha-sma, vimentin, vinculin), integrin expression (alpha1, alpha2, alpha(v) and beta1) and changes in cellularity, we conclude that phenotypically different fibroblast populations are also present during in vivo wound healing. Alpha-sma and the integrin subunits alpha1 and alpha(v) were significantly up-regulated, and vinculin was significantly down-regulated, at early time-points compared to late time-points in wound healing. These changes point to an activated fibroblast state early in wound healing. Later in wound healing, these activated fibroblasts return only partially to the unwounded situation. These results strongly support the idea that different fibroblast populations with specific phenotypes occur in the course of palatal wound healing.
European Journal Of Oral Sciences 05/2005; 113(2):153-8. · 1.88 Impact Factor
