Application of cryopreservation to tooth germ transplantation for root development and tooth eruption.

We cryopreserved mouse tooth germs with widely open cervical margins of the enamel organ to overcome difficulties in cryoprotectant permeation and tested their efficacy by transplanting them into recipient mice. The upper right first molar germs of 8-day-old donor mice were extracted and categorized into the following four groups according to cryopreservation time: no cryopreservation, 1 week, 1 month, and 3 months. The donor tooth germs were transplanted into the upper right first molar germ sockets of the 8-day-old recipient mice. The upper left first molars of the recipient mice were used as controls. The outcome of the transplantation was assessed at 1, 2, and 3 weeks after transplantation. Stereomicroscopic evaluation revealed that most of the transplanted teeth erupted by 3 weeks after transplantation. Micro-computed tomography analysis revealed root elongation in the transplanted groups as well as in the controls. There was no significant difference between the cryopreserved and non-cryopreserved transplanted teeth, but the roots of the cryopreserved teeth were significantly shorter than those of the control teeth. Histological examination revealed root and periodontal ligament formations in all the transplanted groups. These results suggest that the transplantation of cryopreserved tooth germs facilitates subsequent root elongation and tooth eruption.

A prospective longitudinal study of postnatal dentoalveolar and palatal growth: The anatomical basis for CAD/CAM-assisted production of cleft-lip-palate feeding plates.

This study describes the dentoalveolar and palatal growth during the first months of life. Knowledge concerning this development is essential to avoid unwanted events such as mucosal ulcerations or restriction of growth when cleft-lip and palate (CLP) patients are treated. The results involve the generation of CAD/CAM CLP-feeding plates. Intraoral impressions from 32 healthy newborns were taken monthly for 5 months, supplemented by measurements of body weight, length, and occipital-frontal head circumference. The casts were digitalized, and two observers manually selected defined anatomical landmarks on virtual 3-D models. The distances between these landmarks were evaluted. Statistical analysis included an inter-rater agreement analysis and the determination of growth. In total, 213 casts were analyzed, with 65 models excluded because of inaccuracies in impression-taking or cast production. Overall longitudinal growth was 20.3%, whereas transversal growth reached a maximum of 21.1%. Vertical growth was 32.4% at the tuberal level. On the basis of these results, a semiautomated series of feeding plates allowing for monthly expansion could be generated. The acquired data serve as a useful reference for other pediatric and orthofacial investigations and treatments. One such application is the automated, fully virtual manufacture of CLP-feeding plates based on only one impression-taking. Our data reveal when caution is needed to prevent ulceration. The series of plates generated can minimize the time-consuming impression-taking and the production of further plaster models. The method of measurement is suitable for documentary purposes. Clin. Anat. 30:846-854, 2017. © 2017 Wiley Periodicals, Inc.

[Histomorphometric evaluation of ridge preservation after molar tooth extraction].

OBJECTIVE: To evaluate bone formation in human extraction sockets with absorbed surrounding walls augmented with Bio-Oss and Bio-Gide after a 6-month healing period by histologic and histomorphometric analyses. METHODS: Six fresh molar tooth extraction sockets in 6 patients who required periodontally compromised moral tooth extraction were included in this study. The six fresh extraction sockets were grafted with Bio-Oss particle covered with Bio-Gide. The 2.8 mm×6.0 mm cylindric bone specimens were taken from the graft sites with aid of stent 6 months after the surgery. Histologic and histomorphometric analyses were performed. RESULTS: The histological results showed Bio-Oss particles were easily distinguished from the newly formed bone, small amounts of new bone were formed among the Bio-Oss particles, large amounts of connective tissue were found. Intimate contact between the newly formed bone and the small part of Bio-Oss particles was present. All the biopsy cylinders measurement demonstrated a high inter-individual variability in the percentage of the bone, connective tissues and Bio-Oss particles. The new bone occupied 11.54% (0-28.40%) of the total area; the connective tissues were 53.42% (34.08%-74.59%) and the Bio-Oss particles were 35.04% (13.92%-50.87%). The percentage of the particles, which were in contact with bone tissues, amounted to 20.13% (0-48.50%). CONCLUSION: Sites grafted with Bio-Oss particles covered with Bio-Gide were comprised of connective tissues and small amounts of newly formed bone surrounding the graft particles.

Chondral ossification centers next to dental primordia in the human mandible: A study of the prenatal development ranging between 68 to 270mm CRL.

The human mandible is said to arise from desmal ossification, which, however, is not true for the entire body of the mandible: Meckel's cartilage itself is prone to ossification, at least its anterior part in the canine and incisor region. Also, within the coronoid and in the condylar processes there are cartilaginous cores, which eventually undergo ossification. Furthermore, there are a number of additional single cartilaginous islets arising in fetuses of 95mm CRL and more. They are located predominantly within the bone at the buccal sides of the brims of the dental compartments, mostly in the gussets between the dental primordia. They become wedge-shaped or elongated with a diameter of around 150-500µm and were also found in older stages up to 225mm CRL, which was the oldest specimen used in this study. This report is intended to visualize these single cartilaginous islets histologically and in 3-D reconstructions in stereoscopic images. Although some singular cartilaginous tissue within the mandible may be remains of the decaying Meckel's cartilage, our 3-D reconstructions clearly show that the aforementioned cartilaginous islets are independent thereof, as can be derived from their separate locations within the mandibular bone. The reasons that lead to these cartilaginous formations have remained unknown so far.

The remodeling pattern of human mandibular alveolar bone during prenatal formation from 19 to 270mm CRL.

The underlying mechanisms of human bone morphogenesis leading to a topologically specific shape remain unknown, despite increasing knowledge of the basic molecular aspects of bone formation and its regulation. The formation of the alveolar bone, which houses the dental primordia, and later the dental roots, may serve as a model to approach general questions of bone formation. Twenty-five heads of human embryos and fetuses (Radlanski-Collection, Berlin) ranging from 19mm to 270mm (crown-rump-length) CRL were prepared as histological serial sections. For each stage, virtual 3D-reconstructions were made in order to study the morphogenesis of the mandibular molar primordia with their surrounding bone. Special focus was given to recording the bone-remodeling pattern, as diagnosed from the histological sections. In early stages (19-31mm CRL) developing bone was characterized by appositional only. At 41, in the canine region, mm CRL bony extensions were found forming on the bottom of the trough. Besides general apposition, regions with resting surfaces were also found. At a fetal size of 53mm CRL, septa have developed and led to a compartment for canine development. Furthermore, one shared compartment for the incisor primordia and another shared compartment for the molars also developed. Moreover, the inner surfaces of the dental crypts showed resorption of bone. From this stage on, a general pattern became established such that the compartmentalizing ridges and septa between all of the dental primordia and the brims of the crypts were noted, and were due to appositional growth of bone, while the crypts enlarged on their inner surfaces by resorption. By 160mm CRL, the dental primordia were larger, and all of the bony septa had become reduced in size. The primordia for the permanent teeth became visible at 225mm CRL and shared the crypts of their corresponding deciduous primordia.

High-Frequency, Low-Intensity Pulsed Ultrasound Enhances Alveolar Bone Healing of Extraction Sockets in Rats: A Pilot Study.

Most studies of the beneficial effects of low-intensity pulsed ultrasound (LIPUS) on bone healing have used frequencies between 1.0 and 1.5 MHz. However, after consideration of ultrasound wave characteristics and depth of target tissue, higher-frequency LIPUS may have been more effective on superficially positioned alveolar bone. We investigated this hypothesis by applying LIPUS (frequency, 3.0 MHz; intensity, 30 mW/cm(2)) on shaved right cheeks over alveolar bones of tooth extraction sockets in rats for 10 min/d for 2 wk after tooth extraction; the control group (left cheek of the same rats) did not receive LIPUS treatment. Compared with the control group, the LIPUS group manifested more new bone growth inside the sockets on histomorphometric analysis (maximal difference = 2.5-fold on the seventh day after extraction) and higher expressions of osteogenesis-related mRNAs and proteins than the control group did. These findings indicate that 3.0-MHz LIPUS could enhance alveolar bone formation and calcification in rats.

Bone recontouring in fresh sockets with buccal bone loss: a cone beam computed tomography study.

PURPOSE: The aim of this study was to assess buccal bone plate recontouring in maxillary fresh extraction sockets with buccal bone loss using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Healthy patients who required the extraction of one tooth with buccal bone loss in the maxilla were included in this study. CBCT examinations were made before extractions and after 3 months. The alveolar bone levels were assessed from the most coronal, buccal, and palatal bone in which the crest was identified. Buccolingual width at the apical and coronal level was also measured. RESULTS: Fifty healthy patients underwent 50 extractions. Mean bone levels for both single-rooted and multiple-rooted teeth, from a buccopalatal perspective, showed no statistically significant difference between preextraction status and 3 months later. However, in both groups, mean bone levels of the buccal bone plate showed statistically significant differences between extraction and 3 months later. In single-rooted teeth, a mean bone gain of 5.36 ± 2.65 mm was seen after 3 months, and for multiple-rooted teeth, a mean bone gain of 5.89 ± 2.88 mm was seen. Growth in buccolingual width was seen; nevertheless, volume dimensional changes were reported after tooth extraction. CONCLUSIONS: In the first months after extraction, it is possible to observe the formation of buccal bone in sockets with previous buccal bone loss.

Evaluation of simvastatin grafting around immediate dental implants in dogs.

INTRODUCTION: Simvastatin (Zocor; MSD), a cholesterol-lowering drug, is used systemically in treatment of osteoporosis due to its bone-forming potential. The present study was conducted to evaluate the regenerative potential of an optimized simvastatin formulation as a grafting material around immediate dental implants in experimental animals. MATERIALS AND METHODS: The drug was formulated as granules in cellulosic polymeric matrix. Surgical extractions of left and right mandibular third premolars were performed in 10 dogs. The left side of the mandible was the study group, where Microdent (Implant Microdent System S.L-Comapedrosa, Barcelona, Spain) implants were immediately seated and simvastatin granules were packed. The right side constituted the control group where only implants were placed. Five dogs were killed at 1 month and 5 at 3 months. The implants were removed and specimens were processed and stained with hematoxylin and eosin and trichrome stains. RESULTS: Healing occurred in both groups, with better findings in simvastatin-filled defects, as evidenced by bone regeneration, with neovascularization. CONCLUSIONS: Simvastatin granules allowed for osteogenesis around immediate implants, resulting in their osseointegration.

De novo bone regeneration in human extraction sites using recombinant human bone morphogenetic protein-2/ACS: a clinical, histomorphometric, densitometric, and 3-dimensional cone-beam computerized tomographic scan evaluation.

INTRODUCTION: To preserve alveolar bone after extractions, it is important to graft socket sites to prevent bone loss from repair and remodeling. OBJECTIVE: The objective of this case series was to assess the clinical, densitometric, and histomorphometric results from extraction sockets treated with recombinant human bone morphogenetic protein (rhBMP-2/ACS). STUDY DESIGN: After extraction and socket debridement, INFUSE (rhBMP-2) on absorbable sponges was placed over each socket. After 4 months, 3-dimensional cone-beam computerized tomographic (CT) scans were taken. Trephined bone cores were taken as the first step in the implant site osteotomy and submitted for histomorphometric analysis. RESULTS: Histomorphometric analysis showed a mean of 49.6% vital bone with a SD of 10.8%. CT scans showed mean density of 510.6 Hounsfield units. CONCLUSIONS: Use of INFUSE in socket preservation surgery results in adequate de novo bone formation to support ideal implant placement after 4 months.

Creating labial bone for immediate implant placement: a minimally invasive approach by using orthodontic therapy in the esthetic zone.

Orthodontic extrusion of nonrestorable teeth has been used for almost 20 years as an alternative to bone grafting in preparation for implant placement. Although this technique predictably creates bone and soft tissue, and improves the socket diameter and depth, most of the bone apposition occurs in the marginal alveolar and periapical areas of the extruded tooth. To create more labial bone, the standard orthodontic extrusion technique was modified to apply pressure on the hopeless tooth both coronally and palatally, which allowed bone at the site to develop apically and labially. Gingival thickness on the labial aspect was also increased, and the tissue biotype was improved. A clinical treatment is presented that illustrates the use of this technique.

A morphological analysis on the osteocytic lacunar canalicular system in bone surrounding dental implants.

Osseointegration is the most preferable interface of dental implants and newly formed bone. However, the cavity preparation for dental implants often gives rise to empty lacunae or pyknotic osteocytes in bone surrounding the dental implant. This study aimed to examine the chronological alternation of osteocytes in the bone surrounding the titanium implants using a rat model. The distribution of the osteocytic lacunar canalicular system (OLCS) in bone around the titanium implants was examined by silver impregnation according to Bodian's staining. We also performed double staining for alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP), as well as immunohistochemistry for fibroblast growth factor (FGF) 23--a regulator for the serum concentration of phosphorus--and sclerostin, which has been shown to inhibit osteoblastic activities. Newly formed bone and the injured bone at the early stage exhibited an irregularly distributed OLCS and a few osteocytes positive for sclerostin or FGF23, therefore indicating immature bone. Osteocytes in the surrounding bone from Day 20 to Month 2 came to reveal an intense immunoreactivity for sclerostin. Later on, the physiological bone remodeling gradually replaced such immature bone into a compact profile bearing a regularly arranged OLCS. As the bone was remodeled, FGF23 immunoreactivity became more intense, but sclerostin became less so in the well-arranged OLCS. In summary, it seems likely that OLCS in the bone surrounding the dental implants is damaged by cavity formation, but later gradually recovers as bone remodeling takes place, ultimately inducing mature bone.

Histological evaluation of bone regeneration means freeze dried bone allograft (FDBA) in post exodontia sockets / Evaluación histológica de la regeneración ósea en alvéolos post exodoncia mediante uso de freeze dried bone allograft (FDBA)

Within oral rehabilitation alveolar ridge preservation following extraction is important. This research study shows a histological, histochemical and histomorphometrical evaluation in two cases of post extraction ridge-socket preservation performed with FDBA. In two patients dental extraction procedures were performed and sockets were immediately filled with FDBA. Six months later a biopsy of grafted area was obtained and rehabilitated through dental implant. Grafted bone samples were treated for histological and histochemical analysis. Bone tissue area was measured. Laboratory analysis of three samples showed inactive bone surfaces, neither osteoblasts nor osteoclasts were found, only osteocyte and osteogenous cells were observed. These findings do not mean that tissue is metabolically inactive, rather bone genesis develop from a tissue matrix with the potential to generate undifferentiated osteocytes, and a micro environment with proteins such as bone morphogenetic proteins (BPM). Inactive biomaterial particles were not observed. Samples showed 0 percent and 30 percent bone tissue respectively. Considering histological differences between this and other research studies, it is necessary to develop further investigation to increase knowledge of processes involved in bone regeneration as well as bone quality, considering the variability that could be seen in each patient.

Dentro de la rehabilitación oral, es importante preservar el reborde alveolar post exodoncia. Se expone un análisis histológico, histoquímico e histomorfométrico de dos casos clínicos de terapias de regeneración ósea de alvéolos post extracción mediante FDBA. En dos pacientes se extrajeron piezas dentarias destruidas y se indujo regeneración ósea mediante FDBA. Seis meses después, se obtuvo una biopsia del injerto y mediante un implante de titanio fue rehabilitado. Para el análisis Histológico e Histomorfométrico, las muestras fueron tratadas con las técnicas Hematoxilina-Eosina, Azul de Alcián, Masson, Von Kossa y colorante Picrosirius de Junqueira.Se midió el área total de tejido, así como el área de tejido óseo. Las superficies de hueso de las muestras se observaron inactivas, no fueron encontrados osteoblastos ni osteoclastos, sólo osteocitos y células osteógenas, lo que no significa que el hueso esté en estado quiescente, sino mas bien a que su génesis ocurre a partir de la matriz de tejido donde se encuentran células con potencialidad de formar osteocitos indiferenciados y un microambiente con proteinas de la familia de factor de crecimiento transformante beta. No fueron encontradas partículas de biomaterial inactivo. En las muestras se cuantificó 0 por ciento y 30 por ciento de hueso mineralizado. Dadas las diferencias histológicas encontradas con otros estudios, es necesario profundizar el conocimiento en los procesos involucrados en la regeneración ósea dependiendo del biomaterial utilizado, y la calidad ósea resultante en cada procedimiento en particular sin perder de vista la variabilidad que puede presentarse dependiendo de cada caso clínico.

Alveolar bone changes in autogenous tooth transplantation.

OBJECTIVE: To assess the alveolar bone formation after autogenous tooth transplantation by conventional radiographic method and digital subtraction radiography. STUDY DESIGN: This retrospective study was done in 54 of 136 patients who received the third molar tooth transplantation and attended the first week, as well as the 1-, 3-, 6-, 9-, and 12-month follow-up. Postoperative periapical radiographs were subsequently evaluated by direct visual interpretation and digital subtraction radiography. The data were analyzed by using McNemar test and 1-way repeated-measure analysis of variance as well as Bonferroni multiple comparison. RESULTS: Fifty-four cases of transplantation were studied. Most of them had normal wound healing. The direct radiographic interpretation and digital subtraction radiography found significant alveolar bone formation in the first-and the third-month follow-ups (P < .05). Lamina dura appeared in the third month and kept increasing until the sixth month. CONCLUSIONS: Postoperative radiographs revealed the distinctive bone formation up to the third month. The clinical and radiographic assessment found that the third molar transplants could bear a normal chewing load within 3 months.

[Effects of lactational dioxin exposure to development of alveolar bone in SD rat offspring].

OBJECTIVE: To study the influence of lactational dioxin exposure (2, 3, 7, 8-tetrachlorodibenzo-p-dixon, TCDD) on development of alveolar bone in SD rat offspring. METHODS: The rats of TCDD exposure group and control group were sacrificed and the alveolar bone with molars of PD60 rats in the two groups were embedded in resin. The sections were observed by fluorescent microscope. The alveolar bone formation was evaluated by histological examination, tetracycline fluorescence marker and quantitative histomorphometry. The indices of quantitative histomorphometry were compared. RESULTS: The trabecular structure of alveolar bone was looser in TCDD exposure group than in the control group. The tetracycline fluorescence markers were more disorganized in TCDD group. The indices of quantitative histomorphometry of alveolar bone between two groups showed significantly different. CONCLUSIONS: Lactational 2,3,7,8-TCDD exposure decreased the quality and quantity of alveolar bone in SD rat offspring. It is suggested that dioxins exposure may interrupt the spatial configuration.

Growth and the modeling/remodeling of the alveolar bone of the rat incisor.

The modeling and remodeling of the rat incisor alveolar bone was followed as the animals grew. The weight of the hemimandible, the length of the socket, and the width of the lower incisor were measured. Osteoclasts and resorption areas were identified by tartrate-resistant acid phosphatase staining. Fluorochrome markers were used to detect and measure osteogenic activities. In the socket related to the periodontal ligament, osteoclasts appeared in scattered sites as well as isolated sites of osteogenic activity, apparently without any variation related to the age of the animals. At the socket facing the dental follicle of young rats, the inner surface was lined with osteoclasts. The number of osteoclasts decreased steadily as the rats grew. In 1-year-old rats, in addition to a few scattered osteoclasts, the internal aspect of the labial wall showed some sites lined with osteoblasts and cement lines indicative of prior bone formation. In young rats, there was a continuous osteogenic activity at the external surface of this wall. The thickness of the labial wall of the socket remained apparently constant; therefore, bone resorption must have occurred at the internal side of the wall. Such osteogenic activity was not observed in old rats. The main forces acting on rat incisors, biting and eruption, are continuous through the life of the animals. Thus, these results indicate that the modeling of the alveolar bone related to the dental follicle, in young rats, can only be associated with another force, specifically, the growth of the incisor.

Immunolocalization of fibroblast growth factor-2 (FGF-2) in the developing root and supporting structures of the murine tooth.

Epithelio-mesenchymal interactions are active during the development of the root of the tooth and are regulated by a variety of growth factors, such as fibroblast growth factors. FGF-2, 3, 4, and 8 have all been shown to play a role in the development of the crown of the tooth, but less is known about the factors that govern root formation, particularly FGF-2. The aim of this study was thus to elucidate the spatial and temporal expression of FGF-2 in the root of the developing tooth, as this growth factor is believed to be a mediator of epithelio-mesenchymal interactions. Parasagittal sections of the maxillary and mandibular arches of post-natal mice were utilized and the roots of the molar teeth were studied. Immunocytochemistry utilizing an antibody to FGF-2 was performed on sections of teeth at various stages of development. Intense immunostaining for FGF-2 was observed in differentiating odontoblasts at the apical end of the tooth and in the furcation zone of the developing root at all the stages examined. FGF-2 localization was also observed in cementoblasts on post-natal days 16, 20 and 24. The pattern of localization of FGF-2 in the developing root suggests that this growth factor may participate in the signaling network associated with root development.

Acute effects of ovariectomy on wound healing of alveolar bone after maxillary molar extraction in aged rats.

Acute effects of ovariectomy on the bone wound healing processes after maxillary molar extraction in aged rats were examined by means of quantitative scanning electron microscopy (SEM), backscattered electron image (BSE) analysis and energy-dispersive X-ray (EDX) microanalysis. Six-month-old female rats underwent either sham operation or bilateral ovariectomy, and 7 days postoperatively, the maxillary first molars were extracted. On post-extraction days 7, 30 and 60, the dissected maxillary bone surfaces were examined by SEM to reveal the bone formative and resorptive areas around the extracted alveolar sockets. In addition, the resin-embedded maxillae were micromilled in the transverse direction through the extracted alveolar sockets, and the newly-formed bone mass on the buccal bone surfaces and within the extracted sockets was examined by BSE analysis. Compared with sham-operated controls, the extent of newly-formed bone mass on the buccal bone surfaces in OVX rats was significantly decreased, due to increased bone resorption. On the other hand, new bone formation within the extracted sockets was similar in the experimental groups. In EDX microanalysis of these newly-formed bone matrices, both Ca and P weight % and Ca/P molar ratio were similar in the experimental groups. Our results suggest that 1) acute estrogen deficiency induced by ovariectomy stimulates sustained bone resorption, but has less effect on bone formation, and 2) bone wound healing after maxillary molar extraction within extracted alveolar sockets is not significantly delayed by ovariectomy, but bony support by newly-formed bone mass on the maxillary bone surfaces at the buccal side of the extracted sockets is significantly decreased, due to increased bone resorption.

Transplantation of labeled periodontal ligament cells promotes regeneration of alveolar bone.

Regeneration of damaged periodontal tissues is mediated by periodontal cells, but a major sub-population comprises highly differentiated cells that do not renew. To overcome the loss of specialized cell types caused by disease, various therapeutic approaches including cell transplants have been developed to promote cell re-population in periodontal tissues. As previous transplantation studies used unlabeled cells, that are indistinguishable from host cells, it has been difficult to assess the contributions of transplanted cells to the healing processes. To track the fate and differentiation of rat periodontal cells transplanted into periodontal wounds, we used collagen-coated fluorescent beads as a permanent endocytosed marker, or cells constitutively expressing beta-galactosidase. We assessed osteogenic cell differentiation with immunohistochemical staining for osteopontin and bone sialoprotein. Cells were transplanted into periodontal wounds created in Sprague--Dawley male rats that are null for beta-galactosidase. Defects were allowed to heal spontaneously (controls), or were closed with collagen implants mixed with beta-galactosidase-positive (Lac-Z) periodontal cells, or closed with collagen implants mixed with periodontal cells loaded with fluorescent beads. Animals were killed at 1 and 2 weeks after surgery and tissues were prepared for morphometric assessment and immunostaining for osteopontin (OPN) and bone sialoprotein (BSP). Transplanted cells were easily distinguished by fluorescent beads or by beta-galactosidase-positive expression and were distributed throughout the regenerating periodontal ligament (PL) and alveolar bone. At 1 week after wounding, animals treated with beta-galactosidase-positive cells exhibited a slightly higher percentage of labeled cells in the PL compared with the fluorescent bead-labeled cell implant group (2% vs. 1% respectively; P > 0.2). At Week 2 percentages of labeled cells were slightly increased in the regenerating PL (approximately 3% for both groups, P > 0.2). In regenerating alveolar bone at 1 week, animals that were treated with beta-galactosidase-positive cells and fluorescent bead-loaded cells exhibited approximately 30% and 25% of labeled cells respectively. At 2 weeks after wounding there was an increase in the percentage of transplanted beta-galactosidase-positive cells (approximately 39% at week 2; P < 0.05), but not of transplanted cells with fluorescent beads (approximately 25% at week 2). In sites with transplanted cells there were higher percentages of OPN positive and BSP positive cells in nascent bone and more newly formed bone than in controls (>40%; P < 0.05). Transplantation of beta-galactosidase-positive cells or cells loaded with fluorescent beads is a useful method for assessing the fate and differentiation of periodontal cells in vivo. Fluorescent beads, however, are diluted at mitosis and this method underestimates the percentage of transplanted cells. As transplanted periodontal cells in both groups promoted regeneration of alveolar bone, cell transplantation could improve the restoration of periodontium destroyed by periodontitis.