-
Clinical and Experimental Dental... Jun 2023To determine the relationship between different parameters (age, periodontal phenotype, contact point height, and crown shape) and the height of the interproximal...
OBJECTIVES
To determine the relationship between different parameters (age, periodontal phenotype, contact point height, and crown shape) and the height of the interproximal papilla around the teeth of/in the maxillary anterior sector.
MATERIAL AND METHODS
A total of 45 subjects were involved in this study, with 315 interproximal papillae of the maxillary anterior sector. The interproximal papillae were clinically classified according to the Norland and Tarnow classification. The periodontal phenotype was assessed by periodontal probe transparency through the marginal gingiva. The height of the papilla, the height of the contact points, and the width/length ratio of the crown were also measured using the periodontal probe. The relationship between the variables was studied using Pearson's correlation. Statistical significance was set at a value of p < .05.
RESULTS
A positive correlation was found between age and the papilla score. However, a negative correlation was noted between age and papilla height, with statistically significant values. A negative correlation was found between the papilla score and the rest of the studied clinical parameters. However, this correlation was not found with regard to the height of the papilla with the same parameters, except for the height of the contact points.
CONCLUSIONS
A statistically significant relationship was noted between the appearance of the interproximal papillae and all the parameters studied.
Topics: Cross-Sectional Studies; Gingiva; Tooth; Tooth Crown; Crowns
PubMed: 36949730
DOI: 10.1002/cre2.728 -
International Journal of Dentistry 2022The aim of this study was to determine the average and maximum height of the papilla around maxillary anterior implants in respect of neighboring structures and location...
OBJECTIVE
The aim of this study was to determine the average and maximum height of the papilla around maxillary anterior implants in respect of neighboring structures and location of implants.
MATERIALS AND METHODS
92 dental implants from 63 patients were investigated in this study. Those implants were placed in the anterior maxillary region and had been loaded for a minimum of one year. After receiving written consent, clinical data including the height of interproximal papillae adjacent to the tooth/implant/pontic were obtained through clinical observation. The independent -test or ANOVA, the regression modeling, and generalized estimating equation (GEE) models were used for statistical analysis ( < 0.05).
RESULTS
Papilla height was calculated as 2.8 mm (1-5.5 mm) for implant-tooth sites, 2.6 mm (1-4 mm) in implants beside pontics, and 2.5 mm (1-3.5 mm) for implants adjacent to implants. Despite the lack of a significant difference in the mean papilla height in the studied groups, the maximum values of papilla heights were significantly different.
CONCLUSIONS
In this study, no significant differences were found in papilla height mean values in relation to neighboring structures or location of implants in the anterior maxilla. However, the maximum values of papilla heights were observed around implants next to natural teeth.
PubMed: 35186085
DOI: 10.1155/2022/4235946 -
The International Journal of... May 2021SIRT4 is a mitochondrial sirtuin. Owing to its dependance on the cofactor nicotinamide adenine dinucleotide (NAD), SIRT4 can act as a mitochondrial metabolic sensor of...
INTRODUCTION
SIRT4 is a mitochondrial sirtuin. Owing to its dependance on the cofactor nicotinamide adenine dinucleotide (NAD), SIRT4 can act as a mitochondrial metabolic sensor of cellular energy status. We have previously shown that enhancement of mitochondrial functions is vital for the odontogenic diff ;erentiation of dental papilla cells (DPCs) during dentinogenesis. However, whether SIRT4 serves as an effective regulator of DPC diff ;erentiation by affecting mitochondrial functions remains unexplored.
METHODS
Primary DPCs obtained from the first molar dental papilla of neonatal Sprague-Dawley rats were used in this study. The expression pattern of SIRT4 was observed by immunohistochemistry in the first molar of postnatal day 1 (P1) rats. The changes in SIRT4 expression during odontogenic DPC differentiation were evaluated using real-time quantitative polymerase chain reaction (PCR), western blotting, and immunofluorescence. DPCs with loss (small interfering RNA-mediated knockdown) and gain (plasmid transfection-induced overexpression) of SIRT4 function were used to explore the role of SIRT4 in odontogenic differentiation. Mitochondrial function assays were performed using ATP, reactive oxygen species (ROS), and NAD/NADH kits to investigate the potential mechanisms involved in SIRT4-mediated dentinogenesis.
RESULTS
In the present study, we found that SIRT4 expression increased in a time-dependent manner during odontogenic differentiation bothin vivo and in vitro. Sirt4 knockdown resulted in reduced odontogenic differentiation and mineralization, whereas an opposite effect was observed with SIRT4 overexpression. Furthermore, our results verified that in addition to reducing DPC differentiation, Sirt4 knockdown could also significantly reduce ATP levels, elevate the NAD/NADH ratio, and increase ROS levels.
CONCLUSION
SIRT4 regulates mitochondrial functions and the antioxidant capacity of DPCs, thereby influencing dentin formation and tooth development, a phenomenon that may provide a foundation for better understanding the specific molecular mechanisms underlying dentin regeneration.
Topics: Animals; Animals, Newborn; Cell Differentiation; Dental Papilla; Mitochondria; Models, Animal; Odontogenesis; Primary Cell Culture; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Sirtuins
PubMed: 33636397
DOI: 10.1016/j.biocel.2021.105962 -
World Journal of Stem Cells Nov 2021Regenerative endodontics (RE) therapy means physiologically replacing damaged pulp tissue and regaining functional dentin-pulp complex. Current clinical RE procedures... (Review)
Review
Regenerative endodontics (RE) therapy means physiologically replacing damaged pulp tissue and regaining functional dentin-pulp complex. Current clinical RE procedures recruit endogenous stem cells from the apical papilla, periodontal tissue, bone marrow and peripheral blood, with or without application of scaffolds and growth factors in the root canal space, resulting in cementum-like and bone-like tissue formation. Without the involvement of dental pulp stem cells (DPSCs), it is unlikely that functional pulp regeneration can be achieved, even though acceptable repair can be acquired. DPSCs, due to their specific odontogenic potential, high proliferation, neurovascular property, and easy accessibility, are considered as the most eligible cell source for dentin-pulp regeneration. The regenerative potential of DPSCs has been demonstrated by recent clinical progress. DPSC transplantation following pulpectomy has successfully reconstructed neurovascularized pulp that simulates the physiological structure of natural pulp. The self-renewal, proliferation, and odontogenic differentiation of DPSCs are under the control of a cascade of transcription factors. Over recent decades, epigenetic modulations implicating histone modifications, DNA methylation, and noncoding (nc)RNAs have manifested as a new layer of gene regulation. These modulations exhibit a profound effect on the cellular activities of DPSCs. In this review, we offer an overview about epigenetic regulation of the fate of DPSCs; in particular, on the proliferation, odontogenic differentiation, angiogenesis, and neurogenesis. We emphasize recent discoveries of epigenetic molecules that can alter DPSC status and promote pulp regeneration through manipulation over epigenetic profiles.
PubMed: 34909116
DOI: 10.4252/wjsc.v13.i11.1647 -
The Japanese Dental Science Review Nov 2020The establishment of regenerative therapy in endodontics targeting the dentin-pulp complex, cementum, periodontal ligament tissue, and alveolar bone will provide... (Review)
Review
UNLABELLED
The establishment of regenerative therapy in endodontics targeting the dentin-pulp complex, cementum, periodontal ligament tissue, and alveolar bone will provide valuable information to preserve teeth. It is well known that the application of stem cells such as induced pluripotent stem cells, embryonic stem cells, and somatic stem cells is effective in regenerative medicine. There are many somatic stem cells in teeth and periodontal tissues including dental pulp stem cells (DPSCs), stem cells from the apical papilla, and periodontal ligament stem cells. Particularly, several studies have reported the regeneration of clinical pulp tissue and alveolar bone by DPSCs transplantation. However, further scientific issues for practical implementation remain to be addressed. Sphingosine-1-phosphate (S1P) acts as a bioactive signaling molecule that has multiple biological functions including cellular differentiation, and has been shown to be responsible for bone resorption and formation. Here we discuss a strategy for bone regeneration and a possibility for regenerative endodontics targeting S1P signaling pathway as one of approaches for induction of regeneration by improving the regenerative capacity of endogenous cells.
SCIENTIFIC FIELD OF DENTAL SCIENCE
Endodontology.
PubMed: 33088365
DOI: 10.1016/j.jdsr.2020.09.002 -
Theranostics 2020Hertwig's epithelial root sheath (HERS) plays indispensable roles in tooth root development, including controlling the shape and number of roots, dentin formation, and...
Hertwig's epithelial root sheath (HERS) plays indispensable roles in tooth root development, including controlling the shape and number of roots, dentin formation, and helping generate the cementum. Based on these characteristics, HERS cell is a potential seed cell type for tooth-related tissue regeneration. However, the application is severely limited by a lack of appropriate culture methods and small cell numbers. Here, we constructed a 3D culture method to expand functional HERS cells into spheroids, and investigated characteristics and application of dental tissue regeneration of these spheroids. HERS spheroids and HERS cells (2D monolayer culture) were compared in terms of biological characteristics (such as proliferation, self-renewal capacity, and stemness) and functions (including differentiation potential and inductive ability of dentin formation) both and . Further, transcriptome analysis was utilized to reveal the molecular mechanisms of their obvious differences. HERS spheroids showed obvious superiority in biological characteristics and functions compared to 2D monolayers of HERS cells . , HERS spheroids generated more mineralized tissue; when combined with dental papilla cells (DPCs), HERS spheroids contributed to dentin-like tissue formation. Moreover, the generation and expansion of HERS spheroids rely to some degree on the HIF-1 pathway. HERS spheroid generation is beneficial for functional HERS cell expansion and can provide a useful cell source for further tooth regeneration and mechanistic research. Notably, HIF-1 pathway plays a critical role in HERS spheroid formation and function.
Topics: Animals; Cell Differentiation; Cell Proliferation; Cell Self Renewal; Dentin; Epithelial Cells; Female; Hypoxia-Inducible Factor 1; Models, Animal; Odontogenesis; Primary Cell Culture; Rats; Regeneration; Regenerative Endodontics; Spheroids, Cellular; Stem Cells; Tooth Root
PubMed: 32642002
DOI: 10.7150/thno.44782 -
Cureus Nov 2022One of the most popular treatment modalities in routine implantology practice is extraction followed by immediate or delayed implant insertion. Teeth removal alone is... (Review)
Review
One of the most popular treatment modalities in routine implantology practice is extraction followed by immediate or delayed implant insertion. Teeth removal alone is insufficient, particularly in the maxillary anterior region of the jaw. Patients may experience several issues after tooth extractions. Due to trauma and the loss of periodontal ligaments, post-extraction alveolar ridge resorption cannot be prevented. Atraumatic extraction, socket preservation, grafting, and implant placement immediately after the extraction are some of the procedures that are carried out to minimize or prevent the resorption of alveolar bone. Osseointegration is essential for keeping the clinical effectiveness of dental implants. If the supporting tissues at an implant site resorb and are worsened by risk factors for recession, there may be considerable esthetic and functional failure. Implant placement at the retained root structure preserves the buccal bone resulting in an excellent emergence profile. Resorption in the posterior alveolar ridge may result in a decrease in attached keratinized tissue and a decrease in vestibular depth. This might have a negative impact on the stability of the implant and leads to peri-implantitis resulting in the failure of the implant. Without papilla loss or arch collapse, partial extraction therapy has resulted in effective esthetic outcomes. The socket shield technique is a minimally invasive surgical procedure that helps to maintain both soft and hard tissues by preserving a small section of the root. It lessens the necessity for surgeries on bone and mucogingival grafts, cutting the length of the overall recovery process and reducing the treatment time. When soft and hard tissue grafts are used to fill the socket before applying pressure with pontics, it is known as the pontic shield procedure. However, there is no published study that explains partial extraction therapy in a straightforward and clear manner that can guide a practitioner in determining a shield design with a proven track record of success. This review article focuses on the partial extraction procedure which is very helpful for preserving soft and hard tissues in cases involving immediate implant insertion post-extraction. It has long-term therapeutic success with implant and pontic therapy. This review article will also be helpful for clinicians to understand shield design in different case scenarios and help to learn step-wise procedures carried out in partial extraction therapy.
PubMed: 36523724
DOI: 10.7759/cureus.31414 -
Journal of Oral Science Oct 2022Primordial odontogenic tumor (POT) is a rare mixed odontogenic tumor composed of primitive ectomesenchyme similar to the dental papilla. The outer surface consists of...
Primordial odontogenic tumor (POT) is a rare mixed odontogenic tumor composed of primitive ectomesenchyme similar to the dental papilla. The outer surface consists of columnar/cuboidal odontogenic epithelium similar to the inner enamel epithelium, and there is no hard tissue formation. Until now, 27 cases have been reported in the English literature. This article describes the clinicopathological characteristics of one case of POT, representing the oldest patient (aged 26 years) reported to date.
Topics: Adult; Calcinosis; Epithelium; Humans; Jaw Neoplasms; Male; Odontogenic Tumors
PubMed: 36070922
DOI: 10.2334/josnusd.22-0028 -
Frontiers in Physiology 2021circular RNAs (circRNAs) is a broad and diverse endogenous subfamily of non-coding RNAs, regulating the gene expression by acting as a microRNA (miRNA) sponge. However,...
circular RNAs (circRNAs) is a broad and diverse endogenous subfamily of non-coding RNAs, regulating the gene expression by acting as a microRNA (miRNA) sponge. However, the biological functions of circRNAs in odontoblast differentiation remain largely unknown. Our preliminary study identified an unknown mouse circRNA by circRNA sequencing generated from mouse dental papilla and we termed it circKLF4. In this study, quantitative real-time PCR and hybridization were used and demonstrated that circKLF4 was upregulated during odontoblastic differentiation. Gene knockdown and overexpression assays indicated that circKLF4 promoted odontoblastic differentiation of mouse dental papilla cells (mDPCs). Mechanistically, we found that circKLF4 increased the linear KLF4 expression in a microRNA-dependent manner. By mutating the binding sites of microRNA and circKLF4, we further confirmed that circKLF4 acted as sponge of miRNA-1895 and miRNA-5046 to promote the expression of KLF4. We then also found that ENDOGLIN was also up-regulated by circKLF4 by transfection of circKLF4 overexpression plasmids with or without microRNA inhibitor. In conclusion, circKLF4 increases the expression of KLF4 and ENDOGLIN to promote odontoblastic differentiation sponging miRNA-1895 and miRNA-5046.
PubMed: 35222058
DOI: 10.3389/fphys.2021.760223 -
Cureus Mar 2023A patient's ability to maintain a healthy bone-implant interface seems to be a major predictor of implant longevity over the long term. The implant surface is protected...
BACKGROUND
A patient's ability to maintain a healthy bone-implant interface seems to be a major predictor of implant longevity over the long term. The implant surface is protected from the oral environment, the bone, and the implant itself by the peri-implant tissues. Platelet-rich fibrin (PRF) has been shown to help in the regeneration of bone and other connective tissues. Since there has been inadequate information on the role of PRF in maintaining soft tissue integrity and crestal bone changes, the present study aimed to evaluate these challenges clinically and radiographically in human patients who had dental implants placed with PRF.
MATERIALS AND METHODS
There were a total of 15 patients who were recalled for the analysis, and they were split into two groups. PRF was used to complete the implant procedure in the experimental group, but PRF was not used in the control group. Cone beam computed tomography (CBCT) was used to evaluate the amount of alveolar bone prior to dental implant placement and intra-oral periapical radiograph (IOPAR) for postoperative assessment. Gingival index, plaque index, probing depths, papilla bleeding index, and crestal bone changes were used to document clinical limits. IOPAR using a similar approach was used to evaluate the crestal bone level alterations. Patients were evaluated clinically and radiographically for changes in the peri-implant soft tissue and crestal bone during implant placement, six and nine months postoperatively.
RESULTS
From baseline (p=0.02) to six months (p=0.04) and nine months (p=0.04), both groups showed changes in crestal bone loss and soft tissue although the changes in the test group were smaller. Soft tissue changes showed significant differences for probing depth and papilla index score at baseline and at the end of the six and nine months (p<0.05), whereas no significant difference was noted with bleeding index and plaque index score during the follow-up (p>0.05).
CONCLUSION
To conclude, the provided data demonstrated that the local injection of PRF during implant placement has the potential to favorably stimulate bone formation, and may be used as a therapeutic adjuvant in the clinical setting of implant placement.
PubMed: 37128513
DOI: 10.7759/cureus.36908