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The Chinese Journal of Dental Research Sep 2021Tooth eruption is closely linked to the normal development of dentition and proper establishment of occlusion. Disturbances in tooth eruption may affect oral... (Review)
Review
Tooth eruption is closely linked to the normal development of dentition and proper establishment of occlusion. Disturbances in tooth eruption may affect oral physiological functions, facial contour and aesthetics; it is therefore important to understand the eruption process. This process is a complex biological event involving dynamic changes at the tissue and cellular levels. It is guided by anatomical structures as well as biological and molecular factors that result in the movement of the tooth to its final functional position in the oral cavity. Evidence increasingly suggests that stem cells contribute to tooth development and eruption. Multiple stem cell populations have been discovered in teeth and in their supporting tissues, such as dental follicle precursor cells, orofacial bone-/bone marrow-derived mesenchymal stem cells, periodontal ligament stem cells, stem cells from the apical papilla and dental pulp stem cells. These stem cells exhibit distinct differentiation capacities and are closely linked to alveolar bone remodelling, periodontium development and root formation during the eruption process. The present review summarises the current knowledge of the characteristics and functions of orofacial stem cells in tooth eruption, with a particular focus on recent discoveries concerning their lineage allocation and regulatory mechanisms.
Topics: Cell Differentiation; Periodontal Ligament; Stem Cells; Tooth; Tooth Eruption
PubMed: 34491008
DOI: 10.3290/j.cjdr.b1965049 -
Progress in Orthodontics Sep 2023Clear aligner therapy has become increasingly popular in recent years, although it has encountered several difficulties in premolar extraction treatment. These...
INTRODUCTION
Clear aligner therapy has become increasingly popular in recent years, although it has encountered several difficulties in premolar extraction treatment. These difficulties include anterior dentition, lingual tipping and extrusion. The design of the present clinical scheme usually set a tiny space between the anterior teeth before retraction in order to obtain an ideal outcome. The objective of our research was to analyze the effect of the existing spaces during retraction.
METHODS
Models including maxillary dentition without first premolars, maxilla, periodontal ligaments, gingiva, or aligners were constructed and imported to an ANSYS workbench. Five groups of models were created: without spaces and with 0.25, 0.50, 0.75 and 1.00 mm spaces between the anterior dentition. A 0.20 mm retraction step was applied to all the groups.
RESULTS
As the spaces between the anterior dentition increased, the bowing effect of the aligner caused by the passive forces decreased gradually. Accordingly, the degree of extrusion of the anterior dentition was alleviated significantly, while sagittal movement was reduced. However, the overall movement tended to be a bodily displacement rather than tipping. Meanwhile, maximum Von Mises stress of the periodontal ligaments (PDLs) was markedly decreased.
CONCLUSION
These analyses indicate that spaces between the anterior dentition during anterior retraction are beneficial for decreasing the tendency for extrusion of the anterior dentition and require provision of anchorage. Appropriate spaces can be designed to lest the lingual tipping and extrusion effect of the anterior teeth while simultaneously reducing the maximum stresses on PDLs.
Topics: Humans; Bicuspid; Incisor; Finite Element Analysis; Tooth Movement Techniques; Malocclusion; Orthodontic Appliances, Removable
PubMed: 37747552
DOI: 10.1186/s40510-023-00484-1 -
Progress in Orthodontics Nov 2023To investigate the displacement of dentition and stress distribution on periodontal ligament (PDL) during retraction and intrusion of anterior teeth under different...
The displacement of teeth and stress distribution on periodontal ligament under different upper incisors proclination with clear aligner in cases of extraction: a finite element study.
OBJECTIVES
To investigate the displacement of dentition and stress distribution on periodontal ligament (PDL) during retraction and intrusion of anterior teeth under different proclination of incisors using clear aligner (CA) in cases involving extraction of the first premolars.
METHODS
Models were constructed, consisting of the maxilla, PDLs, CA and maxillary dentition without first premolars. These models were then imported to finite element analysis (FEA) software. The incisor proclination determined the division of the models into three groups: Small torque (ST) with U1-SN = 100°, Middle torque (MT) with U1-SN = 110°, and High torque (HT) with U1-SN = 120°. Following space closure, a 200 g intrusion force was applied at angles of 60°, 70°, 80°, and 90° to the occlusal plane, respectively.
RESULTS
CA therapy caused lingual tipping and extrusion of incisors, mesial tipping and intrusion of canines, and mesial tipping of posterior teeth in each group. As the proclination of incisors increased, the incisors presented more extrusion and minor retraction, and the teeth from the canine to the second molar displayed an increased tendency of intrusion. The peak Von Mises equivalent stress (VMES) value successively decreased from the central incisor to the canine and from the second premolar to the second molar, and the VMES of the second molar was the lowest among the three groups. When the angle between the intrusion force and occlusal plane got larger, the incisors exhibited greater intrusion but minor retraction.
CONCLUSIONS
The "roller coaster effect" usually occurred in cases involving premolar extraction with CA, especially in patients with protruded incisors. The force closer to the vertical direction were more effective in achieving incisor intrusion. The stress on PDLs mainly concentrated on the cervix and apex of incisors during the retraction process, indicating a possibility of root resorption.
Topics: Female; Humans; Periodontal Ligament; Incisor; Finite Element Analysis; Molar; Orthodontic Appliances, Removable
PubMed: 37981597
DOI: 10.1186/s40510-023-00491-2 -
The Journal of Clinical Pediatric... 2019Dentinogenesis Imperfecta type II (DI2), also known as hereditary opalescent dentin, is one of the most common genetic disorders affecting the structure of dentin, not... (Review)
Review
Dentinogenesis Imperfecta type II (DI2), also known as hereditary opalescent dentin, is one of the most common genetic disorders affecting the structure of dentin, not related with osteogenesis imperfecta, which involves both primary and permanent dentitions. The purpose of this article is to perform a scoping review of the published peer-reviewed literature (1986-2017) on DI2 management in children and to outline the most relevant clinical findings extracted from this review. Forty four articles were included in the present scoping review. According to the extracted data, the following are the most important tasks to be performed in clinical pediatric dentistry: to re-establish the oral mastication, esthetics, and speech, and the development of vertical growth of alveolar bone and facial muscles; to reduce the tendency to develop caries, periapical lesions and pain; to preserve vitality, form, and size of the dentition; to avoid interfering with the eruption process of permanent teeth; to decrease the risk of tooth fractures and occlusion disturbances; to return the facial profile to a more normal appearance; and to prevent or treat possible temporomandibular joint problems. Therefore, Pediatric Dentists should bear in mind that early diagnosis and treatment, together a long-term follow-up of DI2 in children, continue to be the best approaches for achieving enhanced patient psychological well-being and, in consequence, their quality of life.
Topics: Child; Child, Preschool; Dental Care for Children; Dentinogenesis Imperfecta; Dentition, Permanent; Esthetics, Dental; Humans; Quality of Life
PubMed: 30964718
DOI: 10.17796/1053-4625-43.3.1 -
Journal of Periodontology Dec 2018The efficacy of Coronally Advance Flap (CAF) has been extensively evaluated and several parameters influencing the results, such as interproximal attachment loss,... (Review)
Review
BACKGROUND
The efficacy of Coronally Advance Flap (CAF) has been extensively evaluated and several parameters influencing the results, such as interproximal attachment loss, recession defect size, papilla dimension, flap thickness, have also been identified. However, the influence of tooth location has not been systematically investigated yet. Therefore, the aim of this systematic review was to evaluate the influence of tooth location on the outcomes of CAF.
METHODS
A literature search on PubMed, EMBASE, Cochrane libraries and hand-searched journal until September 2017 was performed to identify clinical studies reporting the outcome of CAF for localized gingival recessions (GRs) for each single tooth.
RESULTS
Eighteen articles reporting 399 localized GRs treated with CAF were included in the present systematic review. Canines and incisors were related to a higher mRC and CRC than premolars and molars (odds ratio 1.63) (p < 0.05), while the right side showed a higher CRC than the left side (odds ratio 1.60) (p < 0.05). No differences were found between maxillary and mandibular dentition (p > 0.05). The addition of a graft such as Connective Tissue Graft (CTG) with or without Enamel Matrix Derivative (EMD) was shown to enhance the outcomes compared to CAF alone (p < 0.05). CRC was negatively affected by initial clinical attachment level (p < 0.05), but not from the initial recession depth (p > 0.05).
CONCLUSIONS
Tooth location plays an important role on mRC and CRC following CAF. The addition of CTG or substitutes, especially with biological agents (EMD), enhance the clinical outcomes compared to CAF alone.
Topics: Connective Tissue; Dental Enamel Proteins; Gingiva; Gingival Recession; Humans; Surgical Flaps; Tooth Root; Treatment Outcome
PubMed: 29963707
DOI: 10.1002/JPER.18-0201 -
Medicina (Kaunas, Lithuania) Mar 2022The periodontium has important proprioceptive receptors that prevent teeth from using excessive occlusal forces during chewing. There are other receptors from adjacent... (Review)
Review
The periodontium has important proprioceptive receptors that prevent teeth from using excessive occlusal forces during chewing. There are other receptors from adjacent tissues that replace periodontal ones when teeth are extracted and rehabilitated with prosthesis, although they seem to be less effective. Psychophysical studies investigate tactile sensibility thresholds, which are useful to measure this masticatory efficiency in different prosthetic rehabilitations. There are two types of sensibility depending on the receptors that are activated during these studies: active and passive tactile sensibility. The purpose of this study is to obtain active and passive tactile sensibility threshold figures in natural dentition and prosthetic rehabilitations so we can compare them and understand how this sensibility works in different situations. We performed a systematic review of the available literature, following PRISMA guidelines and including articles from 2004 to 2021 in the MEDLINE database. Only 10 articles were included in this investigation as they provided concrete threshold figures. The mean values of active tactile sensibility thresholds in complete dentures, implant prosthesis and natural dentition are 64 µ, 23.3 µ and 16.1 µ, respectively. The mean values of passive tactile sensibility thresholds in implant prosthesis and natural dentition are 6.7 N and 0.8 N, respectively. Implant prosthesis have lower thresholds, that are very close to those present in natural dentition, than complete dentures due to an increased tactile sensibility. Active tactile sensibility thresholds present fewer differences between values than passive tactile ones; as these are only influenced by receptors from periodontal or periimplant tissues.
Topics: Dentition; Denture, Complete; Humans; Mouth, Edentulous; Sensory Thresholds; Touch
PubMed: 35454340
DOI: 10.3390/medicina58040501 -
International Journal of Environmental... Mar 2022This prospective study examined a population of 520 urban and rural children aged 5 to 9 years. Every 2−4 weeks, the clinical symptoms accompanying primary tooth...
This prospective study examined a population of 520 urban and rural children aged 5 to 9 years. Every 2−4 weeks, the clinical symptoms accompanying primary tooth replacement such as a cough, a runny nose, pain, and body temperature were assessed in each child’s medical records. The authors were able to show in a statistically significant manner that the frequency, time, and type of cough were strongly related to the type of erupting teeth (p < 0.001 for each relationship). A cough dependent on the type of erupting teeth was observed in 86% to 92% of the examined children, with a morning bronchial cough being connected with an eruption of the lower teeth, and an eruption of the upper teeth producing an all-day pharyngeal cough caused by mucus secretions dripping down the back of the throat. A statistically significant relationship was also confirmed between the type of erupting teeth and the incidence of a runny nose (p < 0.001), the frequency of a runny nose (p < 0.001), and the time when runny nose symptoms occurred (p < 0.001). This study shows that the period when primary dentition is replaced with permanent teeth in children is characterized by a physiological cough and a runny nose.
Topics: Child; Cough; Dentition, Permanent; Humans; Prospective Studies; Tooth; Tooth Eruption
PubMed: 35328989
DOI: 10.3390/ijerph19063301 -
Head & Face Medicine Mar 2023To determine whether odontometric parameters using cone beam computed tomography (CBCT) would aid in sex estimation by assessing sexual dimorphism of odontometric... (Review)
Review
OBJECTIVE
To determine whether odontometric parameters using cone beam computed tomography (CBCT) would aid in sex estimation by assessing sexual dimorphism of odontometric parameters.
MATERIAL AND METHODS
The focused question was whether there is sexual dimorphism in linear and volumetric odontometric parameters when assessed using CBCT. The preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines were followed to conduct a systematic search until June 2022 in all major databases. Data were extracted regarding the population, size of the sample, age range, teeth analyzed, linear or volumetric measurements, accuracy, and conclusion. The quality of included studies was assessed using (Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.
RESULTS
Out of the 3761 studies identified, twenty-nine full-text articles were assessed for eligibility. Finally, twenty-three articles (4215 participants) that provided data on odontometrics using CBCT were included in this systematic review. The odontological sex estimation were assessed either linear measurements (n = 13) or volumetric measurements (n = 8) or both (n = 2). Canines were analysed in maximum number of reports (n = 14), followed by incisors (n = 11), molars(n = 10) and premolars(n = 6). Most of the reports (n = 18) confirmed the existence of sexual dimorphism in odontometric parameters when assessed using CBCT. No significant differences in odontometrics between the sexes were noted in some reports (n = 5). The accuracy of sex estimation was assessed in eight investigations, which ranged from 47.8 to 92.3%.
CONCLUSIONS
Odontometrics of human permanent dentition using CBCT exhibit a certain degree of sexual dimorphism. Both linear and volumetric measurements of teeth can aid sex estimation.
Topics: Humans; Sex Characteristics; Cone-Beam Computed Tomography; Databases, Factual; Incisor; Molar
PubMed: 36882815
DOI: 10.1186/s13005-023-00352-7 -
The Journal of Clinical Pediatric... Jan 2023A great emphasis is currently given to the early correction of malocclusions to prevent further complications if left untreated. Interceptive orthodontics not only... (Review)
Review
A great emphasis is currently given to the early correction of malocclusions to prevent further complications if left untreated. Interceptive orthodontics not only simplifies but also eliminates the need for later procedures. The 2 × 4 appliance is an orthodontic treatment modality applied during the mixed dentition period, particularly for malpositioned permanent upper incisors. This scoping review was aimed to examine the breadth and depth of the published literature on this clinical topic, as well as knowledge gaps, about this fixed appliance during mixed dentition, for the correction of incipient anterior malocclusions (incisor crowdings, midline diastemas, or crossbites). PubMed, Cochrane Library, Google Scholar, Dentistry & Oral Sciences Source, and two grey literature databases were explored; under a structured PICO question (Patient, Intervention, Comparison, Outcome) and eligibility criteria, for relevant clinical trials, observational studies, and case reports/series (in English or Spanish), using different searching terms. Titles and abstracts were screened. Full-text articles were critically reviewed for bias risk and a data charting table was constructed. 161 references were identified, after which 115 titles remained after removing duplicates. After the abstract screening, 18 potential full-text articles were reviewed. Finally, 16 studies were included, according to the performed critical appraisal. The 2 × 4 appliance is suitable for mixed dentition patients with mild or severe malocclusions, particularly when removable appliance usage is a critical problem.
Topics: Humans; Dentition, Mixed; Malocclusion; Orthodontic Appliances, Fixed; Orthodontics, Interceptive; Incisor
PubMed: 36627214
DOI: 10.22514/jocpd.2022.033 -
International Journal of Environmental... Apr 2022This study examined the migratory status/ethnic inequities in dental caries in school children aged 4-9 years ( = 1388) and the impact of the Children's Oral Health...
This study examined the migratory status/ethnic inequities in dental caries in school children aged 4-9 years ( = 1388) and the impact of the Children's Oral Health Program in the Municipality of Bilbao in the Basque Country Region, Spain. Using the 2017 Children's Oral Health Survey, log binomial regression was used to quantify the association of parental immigration status/ethnicity with tooth decay for (1) the primary and the permanent dentitions, separately, in children 4-9 years old; and (2) for the permanent dentition in children aged 7-9 years. Compared with Spanish children, Spanish Roma and immigrant children had a higher probability of tooth decay in primary and permanent teeth after adjustment. Similarly, Spanish Roma and immigrant children had a higher probability of caries experience in primary and permanent teeth. In children aged 7-9 years, Spanish Roma children had a greater probability of tooth decay and caries experience ( index ≥ 1; PR: 6.20; 95% CI: 3.18, 12.12; and PR: 4.52; 95% CI: 2.46, 8.32; respectively) compared with Spanish Children. These associations were not observed in immigrant children. This study shows that parental immigration status and/or ethnicity affect caries outcomes in immigrant and Roma children in both primary and permanent dentition.
Topics: Child; Child, Preschool; DMF Index; Dental Caries; Dentition, Permanent; Emigrants and Immigrants; Ethnicity; Humans; Prevalence; Spain; Tooth, Deciduous
PubMed: 35457355
DOI: 10.3390/ijerph19084487