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BioMed Research International 2017Hypodontia, or tooth agenesis, is the most prevalent craniofacial malformation in humans. It may occur as part of a recognised genetic syndrome or as a nonsyndromic... (Review)
Review
Hypodontia, or tooth agenesis, is the most prevalent craniofacial malformation in humans. It may occur as part of a recognised genetic syndrome or as a nonsyndromic isolated trait. Excluding third molars, the reported prevalence of hypodontia ranges from 1.6 to 6.9%, depending on the population studied. Most affected individuals lack only one or two teeth, with permanent second premolars and upper lateral incisors the most likely to be missing. Both environmental and genetic factors are involved in the aetiology of hypodontia, with the latter playing a more significant role. Hypodontia individuals often present a significant clinical challenge for orthodontists because, in a number of cases, the treatment time is prolonged and the treatment outcome may be compromised. Hence, the identification of genetic and environmental factors may be particularly useful in the early prediction of this condition and the development of prevention strategies and novel treatments in the future.
Topics: Anodontia; Bicuspid; Humans; Incisor; Mandible; Maxilla
PubMed: 28401166
DOI: 10.1155/2017/9378325 -
Progress in Orthodontics Jan 2023The present study was designed to define: (1) which are the less predictable OTM with Invisalign aligners when the treatment plan is designed by expert operators, (2) if...
BACKGROUNDS
The present study was designed to define: (1) which are the less predictable OTM with Invisalign aligners when the treatment plan is designed by expert operators, (2) if the presence and shape of attachments influence the predictability of OTM and (3) if patients' demographics influence OTM predictability. The sample comprises 79 prospectively recruited patients (mean age 30.8 years; SD 12.0; 23 M, 56 F), treated by expert operators with an average of 27 aligners (SD 15) in the maxillary arch and 25 aligners (SD 11) in the mandibular arch. Post-treatment digital models and final virtual treatment plan models were exported from ClinCheck software as STL files and subsequently imported into Geomagic Qualify software, to compare final teeth positions. The differences were calculated and tested for statistical significance for each tooth in the mesial-distal, vestibular-lingual and occlusal-gingival directions, as well as for angulation, inclination and rotation. In addition, the statistical significance of categorical variables was tested.
RESULTS
The lack of correction was significant for all movements and in all group of teeth (P < 0.01) except for the rotation of maxillary first molar. The prescribed OTM, the group of teeth and movement, the frequency of aligner change and the use of attachment influence the outcome. The greatest discrepancies in predicted and achieved tooth position were found for angular movements and rotation of teeth characterized by round-shaped crowns, for a ratio of approximately 0.4° per 1° prescribed. Optimized attachments for upper canines and lower premolar rotation seem not working properly. Second molar movements are mostly unexpressed. Furthermore, changing the aligner every 14 days will reduce the lack of correction of the 12% with respect to 7 days aligner change.
CONCLUSIONS
Predictability of orthodontic movement with aligners still has limitations related to the biomechanics of the system: the shape of some attachments and the characteristics of aligner material need to be redefined. However, the results of this study allow to properly design the virtual treatment plan, revealing how much overcorrection is needed and which attachments are most effective.
Topics: Tooth Movement Techniques; Software; Orthodontic Appliances, Removable; Molar; Bicuspid
PubMed: 36642743
DOI: 10.1186/s40510-022-00453-0 -
Dental Press Journal of Orthodontics Aug 2019Tooth crowding and protrusions demand rigorous attention during orthodontic planning that includes the extraction of first and second premolars. Some characteristics,...
Tooth crowding and protrusions demand rigorous attention during orthodontic planning that includes the extraction of first and second premolars. Some characteristics, such as dentoalveolar bone discrepancies, maxillomandibular relations, facial profile, skeletal maturation, dental asymmetries and patient cooperation, are important elements of an orthodontic diagnosis. This study discusses the options of treatments with extractions and describes the correction of a Class I malocclusion, bimaxillary protrusion, severe anterior crowding in both dental arches and tooth-size discrepancy, using first premolar extractions.
Topics: Bicuspid; Cephalometry; Humans; Malocclusion, Angle Class I; Orthodontics; Orthodontics, Corrective; Tooth Extraction
PubMed: 31390455
DOI: 10.1590/2177-6709.24.3.088-098.bbo -
Australian Dental Journal Dec 2019The extraction of permanent molar teeth was first introduced in 1976 as a substitution for premolar extraction in cases with mild crowding. Since then, a number of... (Review)
Review
The extraction of permanent molar teeth was first introduced in 1976 as a substitution for premolar extraction in cases with mild crowding. Since then, a number of studies have investigated the effect of permanent molar extraction on dentofacial harmony. Undertaking the procedure of molar extraction is most commonly recommended in response to factors such as: gross caries, large restorations and root-filled teeth, along with its application in the management of anterior open bite and reduction in crowding in facial regions. It has been indicated, however, that before undertaking the extraction of molar teeth it is important to investigate the potential influence of the procedure on other molars, with particular consideration of their eruption path. This is due to the doubt as to the effect of the exact molar teeth extraction and their consequences. In light of this, This review was undertaken to investigate and compare the effect of first, second and the third molar teeth extraction and their subsequent dentofacial complex changes.
Topics: Bicuspid; Humans; Molar; Molar, Third; Tooth Eruption; Tooth Extraction
PubMed: 31465537
DOI: 10.1111/adj.12716 -
Head & Face Medicine Mar 2018Primary failure of eruption (PFE) is a rare disease defined as incomplete tooth eruption despite the presence of a clear eruption pathway. Orthodontic extrusion is not...
BACKGROUND
Primary failure of eruption (PFE) is a rare disease defined as incomplete tooth eruption despite the presence of a clear eruption pathway. Orthodontic extrusion is not feasible in this case because it results in ankylosis of teeth. To the best of our knowledge, besides the study of Ahmad et al. (Eur J Orthod 28:535-540, 2006), no study has systematically analysed the clinical features of and factors associated with PFE. Therefore, the aim of this study was to systematically evaluate the current literature (from 2006 to 2017) for new insights and developments on the aetiology, diagnosis, genetics, and treatment options of PFE.
METHODS
Following the PRISMA guidelines, a systematic search was performed using the PubMed/Medline database for studies reporting on PFE. The following terms were used: "primary failure of tooth eruption", "primary failure of eruption", "tooth eruption failure", and "PFE".
RESULTS
Overall, 17 articles reporting clinical data of 314 patients were identified. In all patients, the molars were affected. In 81 reported cases, both the molars and the premolars were affected by PFE. Further, 38 patients' primary teeth were also affected. In 27 patients, no family members were affected. Additional dental anomalies were observed in 39 patients. A total of 51 different variants of the PTH1R gene associated with PFE were recorded.
CONCLUSIONS
Infraocclusion of the posterior teeth, especially if both sides are affected, is the hallmark of PFE. If a patient is affected by PFE, all teeth distal to the most mesial tooth are also affected by PFE. Primary teeth can also be impacted; however, this may not necessarily occur. If a patient is suspected of having PFE, a genetic test for mutation in the PTH1R gene should be recommended prior to any orthodontic treatment to avoid ankylosis. Treatment options depend on the patient's age and the clinical situation, and they must be evaluated individually.
Topics: Age Factors; Bicuspid; Child, Preschool; Female; Follow-Up Studies; Humans; Infant; Male; Molar; Orthodontic Extrusion; Radiography, Panoramic; Sex Factors; Tooth Ankylosis; Tooth Eruption; Tooth, Deciduous; Tooth, Unerupted
PubMed: 29544499
DOI: 10.1186/s13005-018-0163-7 -
BMC Oral Health Jun 2021The present study aimed to investigate the effects of low-level laser therapy (LLLT) on orthodontic tooth movement and its correlation with the levels of interleukin-1β... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The present study aimed to investigate the effects of low-level laser therapy (LLLT) on orthodontic tooth movement and its correlation with the levels of interleukin-1β (IL-1β), receptor activator of nuclear factor kappa B ligand (RANKL) and osteoprotegerin (OPG) in gingival crevicular fluid (GCF).
METHODS
This split-mouth design study included 12 patients scheduled for the extraction of both upper first premolars. Patients were randomly selected for experimental group that received left- or right-side radiation with a diode laser (810 nm wavelength, 100 mW power output, 6.29 J/cm energy density). Laser treatment was applied on days 0, 7, 14, and 21, after loading the canine retraction forces. GCF concentrations of IL-1β, RANKL, and OPG were analyzed. The upper arch of each patient was scanned with an intraoral scanner to assess tooth movement.
RESULTS
The cumulative tooth movement over 28 days was significantly higher in the laser group than in the control group. We observed significant reductions in OPG levels and increases in IL-1β and RANKL levels in GCF samples on the experimental sides.
CONCLUSION
With the parameter settings used in this study, LLLT could, to some extent, lead to changes in bone metabolism, which could accelerate orthodontic tooth movement.
TRIAL REGISTRATION
Chinese Clinical Trial Registry, ChiCTR2000039594. Registered 2 November 2020-Retrospectively registered, www.chictr.org.cn/edit.aspx?pid=62465&htm=4 .
Topics: Bicuspid; Gingival Crevicular Fluid; Humans; Lasers, Semiconductor; Low-Level Light Therapy; Tooth Movement Techniques
PubMed: 34182967
DOI: 10.1186/s12903-021-01684-z -
Progress in Orthodontics Dec 2022The purpose was to determine the predictability of tooth movements through clear aligner among premolar extraction patients and to explore the effects of various factors...
BACKGROUND
The purpose was to determine the predictability of tooth movements through clear aligner among premolar extraction patients and to explore the effects of various factors on tooth movements.
METHODS
A total of 31 extraction patients (10 males and 20 females; age 14-44) receiving clear aligner treatment (Invisalign) were enrolled in this study. The actual post-treatment models and pre-treatment models were superimposed using the palatal area as a reference and registered with virtual post-treatment models. A paired t test was used to compare the differences between actual and designed tooth movements of maxillary first molars, canines, and central incisors. A multivariate linear mixed model was performed to examine the influence of variables on actual tooth movements.
RESULTS
Compared to the designed tooth movements, the following undesirable tooth movements occurred: mesial movement (2.2 mm), mesial tipping (5.4°), and intrusion (0.45 mm) of first molars; distal tipping (11.0°), lingual tipping (4.4°), and distal rotation of canines (4.9°); lingual tipping (10.6°) and extrusion (1.5 mm) of incisors. Age, crowding, mini-implant, overbite, and attachments have differential effects on actual tooth movements. Moreover, vertical rectangular attachments on canines are beneficial in achieving more predictable canine and incisor tooth movements over optimized attachments. Lingual tipping and extrusion of incisors were significantly influenced by the interaction effects between incisor power ridge and different canine attachments (p < 0.05).
CONCLUSIONS
Incisors, canines, and first molars are subject to unwanted tooth movements with clear aligners among premolar extraction patients. Age, crowding, mini-implant, overbite, and attachments influence actual tooth movements. Moreover, vertical rectangular attachments on canines are beneficial in achieving more predictable incisor tooth movements over optimized canine attachments.
Topics: Male; Female; Humans; Bicuspid; Overbite; Tooth Movement Techniques; Malocclusion; Orthodontic Appliances, Removable; Malocclusion, Angle Class II; Multivariate Analysis
PubMed: 36581703
DOI: 10.1186/s40510-022-00447-y -
The Journal of Thoracic and... Jul 2019
Topics: Aorta; Aortic Valve; Bicuspid; Humans; Replantation; Tricuspid Valve
PubMed: 31248515
DOI: 10.1016/j.jtcvs.2018.10.158 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Feb 2024To provide references, this study investigated the clinical characteristics of patients with nonsyndromic oligodontia.
OBJECTIVES
To provide references, this study investigated the clinical characteristics of patients with nonsyndromic oligodontia.
METHODS
The information of 178 patients with oligodontia was collected, including histories, oral examinations, and panoramic radiographs. Tooth agenesis characteristics were calculated and evaluated. All the data were statistically analyzed with SPSS 24.0 software.
RESULTS
No significant difference in the number of missing teeth was found between sexes nor between the right and left sides, and congenitally missing teeth affected the maxillary arch (<0.05). The highest prevalence of tooth agenesis was observed in the mandibular second premolars. In the maxillary arch, the most common pattern of tooth agenesis was agenesis of the bilateral first and second premolars. The agenesis of the bilateral second premolars was observed in the mandibular arch. The prevalence of a symmetric pattern between the right and left quadrants was significantly higher than that of matched patterns between the maxillary and mandibular antagonistic quadrants. Approximately 16.85% of patients with nonsyndromic oligodontia were affected by other tooth-related anomalies
CONCLUSIONS
The common patterns of tooth agenesis were successfully identified in patients with nonsyndromic oligodontia. Dentists need to provide multidisciplinary treatments for patients with nonsyndromic oligodontia because of variations in occluding and full-mouth tooth agenesis patterns.
Topics: Humans; Anodontia; Tooth Abnormalities; Bicuspid; Maxilla; Phenotype; Prevalence
PubMed: 38475956
DOI: 10.7518/hxkq.2024.2023203 -
American Journal of Orthodontics and... Oct 2022Orthodontists, surgeons, and patients have taken an interest in using clear aligners in combination with orthognathic surgery. This study aimed to evaluate the accuracy...
INTRODUCTION
Orthodontists, surgeons, and patients have taken an interest in using clear aligners in combination with orthognathic surgery. This study aimed to evaluate the accuracy of tooth movements with clear aligners during presurgical orthodontics using novel 3-dimensional superimposition techniques.
METHODS
The study sample consisted of 20 patients who have completed presurgical orthodontics using Invisalign clear aligners. Initial (pretreatment) digital dental models, presurgical digital dental models, and ClinCheck prediction models were obtained. Presurgical models were superimposed onto initial ones using stable anatomic landmarks; ClinCheck models were superimposed onto presurgical models using surface best-fit superimposition. Five hundred forty-five teeth were measured for 3 angular movements (buccolingual torque, mesiodistal tip, and rotation) and 4 linear movements (buccolingual, mesiodistal, vertical, and total scalar displacement). The predicted tooth movement was compared with the achieved amount for each movement and tooth, using both percentage accuracy and numerical difference.
RESULTS
Average percentage accuracy (63.4% ± 11.5%) was higher than in previously reported literature. The most accurate tooth movements were buccal torque and mesial displacement compared with lingual torque and distal displacement, particularly for mandibular posterior teeth. Clinically significant inaccuracies were found for the buccal displacement of maxillary second molars, lingual displacement of all molars, intrusion of mandibular second molars, the distal tip of molars, second premolars, and mandibular first premolars, buccal torque of maxillary central and lateral incisors, and lingual torque of premolars and molars.
CONCLUSIONS
Superimposition techniques used in this study lay the groundwork for future studies to analyze advanced clear aligner patients. Invisalign is a treatment modality that can be considered for presurgical orthodontics-tooth movements involved in arch leveling and decompensation are highly accurate when comparing the simulated and the clinically achieved movements.
Topics: Bicuspid; Humans; Incisor; Maxilla; Orthodontic Appliances, Removable; Tooth Movement Techniques
PubMed: 36182208
DOI: 10.1016/j.ajodo.2021.12.019