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JNMA; Journal of the Nepal Medical... Mar 2021Molar and incisor hypomineralization is a developmental defect that is systemic in origin that affects one or more than one permanent first molars, and is often... (Review)
Review
Molar and incisor hypomineralization is a developmental defect that is systemic in origin that affects one or more than one permanent first molars, and is often associated with permanent incisors. It is usually characterized by well demarcated opacities and qualitative enamel defects caused by decreased inorganic enamel components, and reduced mineralization. It can cause esthetic, functional, psychological, and behavioral problems in children. Its reported prevalence varies widely, from 2.5% to 40.2%. Multiple aspects of dental treatment for it are challenging, such as behavior management, difficulty in achieving adequate local anesthesia, tooth hypersensitivity, and retention of restorations. This review discusses the most important considerations pertaining to its prevalence, severity, etiology, differential diagnosis, and some of the challenges and treatment modalities applicable in young patients. Data is collected from PubMed, Medline, and Embase databases.
Topics: Child; Diagnosis, Differential; Humans; Incisor; Molar; Prevalence
PubMed: 34506432
DOI: 10.31729/jnma.6343 -
Medicina Oral, Patologia Oral Y Cirugia... Jan 2022The main objective of this systematic review was to collect the pre-existing scales for assessing the difficulty of third molar extraction. The secondary objective was...
BACKGROUND
The main objective of this systematic review was to collect the pre-existing scales for assessing the difficulty of third molar extraction. The secondary objective was to design a proposal for a preoperative evaluation protocol for the difficulty of third molar extraction.
MATERIAL AND METHODS
Two independent researchers conducted an electronic search in Pubmed (MEDLINE), Cochrane, and Scopus databases during March 2021. Included studies evaluated the prediction of the difficulty of surgical removal of impacted upper or lower third molars using new indices/scales or pre-existing scales with or without modifications. Articles referring to coronectomies or assessing pre-surgical difficulty using other tools were excluded. Neither language nor publication date restrictions were applied.
RESULTS
Out of 242 articles, 13 prospective cohort studies were finally selected. Seven developed new indices/scales, and 6 assessed the predictive ability of some pre-existing scales. Most of the indices/scales contained radiological variables and few added any patient-related variables. We proposed a preoperative assessment protocol of the difficulty of third molar extraction to facilitate treatment planning and/or considerate referral in cases of high difficulty. This proposal used patient-related, radiological and surgical variables.
CONCLUSIONS
Using a preoperative protocol to evaluate the surgical difficulty, including different patient-specific, radiological and surgical variables, could facilitate treatment planning, help clinicians prevent complications and assess the possibility of referral.
Topics: Humans; Molar, Third; Prospective Studies; Tooth Extraction; Tooth, Impacted
PubMed: 34874928
DOI: 10.4317/medoral.24951 -
PloS One 2021Molar incisor hypomineralization (MIH) is an enamel condition characterized by lesions ranging in color from white to brown which present rapid caries progression, and... (Clinical Trial)
Clinical Trial
Molar incisor hypomineralization (MIH) is an enamel condition characterized by lesions ranging in color from white to brown which present rapid caries progression, and mainly affects permanent first molars and incisors. These enamel defects usually occur when there are disturbances during the mineralization or maturation stage of amelogenesis. Both genetic and environmental factors have been suggested to play roles in MIH's development, but no conclusive risk factors have shown the source of the disease. During head and neck development, the interferon regulatory factor 6 (IRF6) gene is involved in the structure formation of the oral and maxillofacial regions, and the transforming growth factor alpha (TGFA) is an essential cell regulator, acting during proliferation, differentiation, migration and apoptosis. In this present study, it was hypothesized that these genes interact and contribute to predisposition of MIH. Environmental factors affecting children that were 3 years of age or older were also hypothesized to play a role in the disease etiology. Those factors included respiratory issues, malnutrition, food intolerance, infection of any sort and medication intake. A total of 1,065 salivary samples from four different cohorts were obtained, and DNA was extracted from each sample and genotyped for nine different single nucleotide polymorphisms. Association tests and logistic regression implemented in PLINK were used for analyses. A potential interaction between TGFA rs930655 with all markers tested in the cohort from Turkey was identified. These interactions were not identified in the remaining cohorts. Associations (p<0.05) between the use of medication after three years of age and MIH were also found, suggesting that conditions acquired at the age children start to socialize might contribute to the development of MIH.
Topics: Adolescent; Amelogenesis; Child; Dental Enamel Hypoplasia; Female; Gene-Environment Interaction; Genotype; Humans; Incisor; Male; Molar; Polymorphism, Single Nucleotide; Transforming Growth Factor alpha
PubMed: 33406080
DOI: 10.1371/journal.pone.0241898 -
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 -
Science Progress 2021To evaluate the associations of impaction patterns of mandibular third molars (M3Ms) with pathologies caused by them. In this study, 262 patients with 432 impacted M3Ms...
To evaluate the associations of impaction patterns of mandibular third molars (M3Ms) with pathologies caused by them. In this study, 262 patients with 432 impacted M3Ms who referred in Shanghai Xuhui District Center were reviewed. The pathologies include pericoronitis, mandibular second molar (M2M) caries, and M2M distal periodontal pathology. The impaction patterns of M3Ms and the pathologies were examined, while the M2M outcomes after surgeries were evaluated. A χ test was used to analyze the data, with a value of <0.05 being considered statistically significant. Pericoronitis was the major symptom in all patients, whereas the propensities of M2M distal caries and periodontal pathologies increased in older patients. Soft tissue impacted and vertically angulated teeth were more associated with pericoronitis ( < 0.05); mesio-angular impacted teeth in less deep positions had greater risks of M2Ms distal caries ( < 0.05); mesio-angular and horizontal impacted teeth in relative deep positions were more likely to cause M2Ms distal periodontal pathologies ( < 0.05). Extractions of soft tissue impacted teeth in vertical angulations should be considered, while removals of mesially and horizontally angulated or bony impacted teeth could be delayed.
Topics: Aged; China; Humans; Mandible; Molar, Third; Pericoronitis; Tooth, Impacted
PubMed: 33913399
DOI: 10.1177/00368504211013247 -
Zhong Nan Da Xue Xue Bao. Yi Xue Ban =... Oct 2021At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to...
OBJECTIVES
At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to evaluate the therapeutic effect of mandibular molars distalization with clear aligner via cone beam CT (CBCT) and Dolphin software.
METHODS
Twenty cases of mandibular molars with clear aligner were included according to the inclusion and exclusion criteria. CBCT was taken before treatment (T0) and when the first molar was moved in place (T1). Dolphin software was used to measure the effectiveness of molar distalization. Three-dimensional changes in direction and the impact on the incisors and facial soft and hard tissues were evaluated.
RESULTS
The effective rates of crown and root distalization of the second and first mandibular molars were 74%, 49%, and 71%, 47%, respectively. The second and first molars were both the distal buccal cusp with the largest distalization [(2.15 ± 0.91) mm and (1.85±1.09) mm], respectively, with significant difference between the T0 and T1 (<0.05). The second and first molars were accompanied by depression, distal tilt, and buccal tilt with 1.06 mm, 2.10°, 2.27°, and 0.91 mm, 1.62°, and 1.91°, respectively, with significant differences between the T0 and T1 (all <0.05). There was no obvious difference between men and women. The mandibular central incisor showed a lip-side movement of 1.02 mm, a depression of 0.82 mm, a mesial incline of 0.66°, and a crown-lip torque of 1.51° after molar distalization, with significant differences between the T0 and T1 (all <0.001). Only the lower lip thickness increased by 0.1 cm, the length of the lower lip increased by 0.1 cm, and the ANS-ME (distance from anterior nasal spine to submental point) decreased by 0.13 cm, with significant differences between the T0 and T1 (all <0.05).
CONCLUSIONS
Clear aligner can effectively move mandibular molars farther, the crown is more effective than the root, and it is tilted. The second mandibular molar is more effective than the first mandibular molar in its distant displacement and three-dimensional changes. Molar distalization causes minor changes in mandibular incisors and facial soft and hard tissues.
Topics: Cephalometry; Maxilla; Molar; Orthodontic Appliances, Removable; Tooth Movement Techniques
PubMed: 34911842
DOI: 10.11817/j.issn.1672-7347.2021.200391 -
Journal of Dentistry Aug 2020To compare the survival of restorations placed in deep caries lesions after selective caries removal to soft dentin (SCRSD) over a 5-year period. A secondary aim was to... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To compare the survival of restorations placed in deep caries lesions after selective caries removal to soft dentin (SCRSD) over a 5-year period. A secondary aim was to investigate whether the material (amalgam or resin composite) affected the survival of restorations.
METHODS
This study used data derived from a multicenter randomized controlled clinical trial (Clinical trials registration NCT00887952). Inclusion criteria were: patients with permanent molars presenting occlusal or proximal deep caries lesions (≥1/2 of the dentin thickness on radiographic examination), positive response to a cold test, absence of spontaneous pain, negative sensitivity to percussion, and absence of periapical lesions. The teeth were randomized into SCRSD and restoration in a single visit or stepwise excavation (SW). Each of these groups was divided according to the filling material: amalgam (AM) or resin composite (RC). Survival analyses were performed to estimate therapy success rates over 5 years (adjusted Weibull regression model).
RESULTS
172 restorations were evaluated, 95 from SCRSD group and 77 from SW group, being 61 AMG and 111 RC. The 5-year survival analysis showed similar success rates for SW (76 %) and SCRSD (79 %) as well as for AM and RC (p > 0.05).
CONCLUSION
This study showed that, after a 5-year follow-up period, the presence of decayed tissue beneath restorations in deep caries lesions did not seem to affect restoration survival. Amalgam and resin composite restorations had similar survival rates, irrespective of the caries removal technique used - SCRSD or SW.
CLINICAL SIGNIFICANCE
Selective caries removal to soft dentin can be used in the management of deep caries to avoid pulp exposure and preserve tooth structure without affecting restoration longevity.
Topics: Composite Resins; Dental Caries; Dental Restoration Failure; Dental Restoration, Permanent; Dentin; Humans; Molar
PubMed: 32585263
DOI: 10.1016/j.jdent.2020.103416 -
BMC Oral Health Dec 2022The effects of upper-molar distalization using clear aligners in combination with Class II elastics for anchorage reinforcement have not been fully investigated yet. The...
INTRODUCTION
The effects of upper-molar distalization using clear aligners in combination with Class II elastics for anchorage reinforcement have not been fully investigated yet. The objective of this study is to analyze the movement and stress of the whole dentition and further explore guidelines for the selection of traction methods.
METHODS
Three-dimensional (3D) finite element models are established to simulate the sequential molar distalization process, including the initial distalization of the 2 molar (Set I) and the initial distalization of the 1 molar (Set II). Each group set features three models: a control model without Class II elastics (model A), Class II elastics attached to the tooth by buttons (model B), and Class II elastics attached to the aligner by precision cutting (model C). The 3D displacements, proclination angles, periodontal ligament (PDL) hydrostatic stress and alveolar bone von Mises stress in the anterior area are recorded.
RESULTS
In all of the models, the maxillary anterior teeth are labial and mesial proclined, whereas the distal moving molars exhibit distal buccal inclination with an extrusion tendency. With the combination of Class II elastics, the anchorage was effectively reinforced; model C demonstrates superior anchorage reinforcement with lower stress distribution in comparison with model B. The upper canines in model B present an extrusion tendency. Meanwhile, the mandibular dentition in models B and C experience undesired movement tendencies with little discrepancy from each other.
CONCLUSIONS
Class II elastics are generally effective for anchorage reinforcement as the upper-molar distalization is performed with clear aligners. Class II elastics attached to an aligner by precision cutting is a superior alternative for maxillary anchorage control in cases that the proclination of upper incisors and extrusion of upper canines are unwanted.
Topics: Finite Element Analysis; Molar; Incisor; Periodontal Ligament; Orthodontic Appliances, Removable
PubMed: 36456944
DOI: 10.1186/s12903-022-02526-2 -
Dental Materials : Official Publication... Nov 2021The study aimed to evaluate survival and failure behavior of Direct Composite Restorations (DRC) and Indirect Composite Restorations (ICR) on molars and anterior teeth,... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
The study aimed to evaluate survival and failure behavior of Direct Composite Restorations (DRC) and Indirect Composite Restorations (ICR) on molars and anterior teeth, in a Randomized Controlled Trial (RCT).
METHODS
Patients with generalized severe tooth wear were included, and randomly assigned to one of 2 protocols: (1) DCR: All teeth were restored with directly applied micro-hybrid composite restorations (Clearfil AP-X, Kuraray) for load bearing areas and nano-hybrid composite restorations (IPS Empress Direct, Ivoclar Vivadent) for buccal veneers; (2) ICR: First molars were restored with indirect composite 'tabletop' restorations and maxillary anterior teeth were restored with indirect palatal veneer restorations (Clearfil Estenia C&B, cemented with Panavia F, Kuraray). Remaining teeth were restored directly. Restorations were evaluated after 3 years, focusing on clinical acceptability. Statistical analysis was performed using Kaplan Meier curves, Annual Failure Rates (AFRs), and univariate Cox regression analyses (p < 0.05).
RESULTS
41 patients (age: 36.6 ± 6.6y) were evaluated after 3 years (40.0 ± 2.2 m). 408 restorations on first molars and palatal veneers on maxillary anterior teeth were part of this RCT, with 220 DCRs and 188 ICRs. No differences in survival between treatment modality for palatal veneers for any failure criteria were found. Tabletop restorations on first molars showed a considerable higher failure rate for ICR compared to DCR (p = 0.026, HR: 3.37, 95%CI = 1.16-9.81).
SIGNIFICANCE
In this RCT, directly applied composite restorations showed superior behavior compared to the indirect composite restorations, when used in the molar region.
Topics: Adult; Dental Materials; Dental Restoration Failure; Dental Veneers; Humans; Molar; Tooth Wear
PubMed: 34497023
DOI: 10.1016/j.dental.2021.08.018 -
Progress in Orthodontics Sep 2020The aim of this systematic review and meta-analysis is to assess the degree of stability of anterior open bite (AOB) treatment performed through the molar intrusion... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
The aim of this systematic review and meta-analysis is to assess the degree of stability of anterior open bite (AOB) treatment performed through the molar intrusion supported with skeletal anchorage at least 1 year posttreatment.
METHODS
This study was registered in PROSPERO (CRD42016037513). A literature search was conducted to identify randomized (RCT) or non-randomized clinical trials based including those considering before and after design. Data sources were electronic databases including PubMed, Cochrane Library, Science Direct, Google Scholar, Scopus, Lilacs, OpenGrey, Web of Science, and ClinicalTrials.gov . The quality of evidence was assessed through the JBI tool and certainty of evidence was evaluated through the GRADE tool. Random effects meta-analysis was conducted when appropriate.
RESULTS
Six hundred twenty-four articles met the initial inclusion criteria. From these, only 6 remained. The mean posttreatment follow-up time was 2.5 years (SD = 1.04). The overbite showed a standardized mean relapse of - 1.23 mm (95% CI - 1.64, - 0.81, p < 0.0001). Maxillary and mandibular incisors presented a non-significant mean relapse, U1-PP - 0.04 mm (95% CI - 0.55, 0.48) and L1-MP - 0.10 mm (95% CI - 0.57, 0.37). Molar intrusion showed a relapse rate around 12% for the maxillary molars and a 27.2% for mandibular molars.
CONCLUSION
The stability of AOB through molar intrusion using TADs can be considered relatively similar to that reported to surgical approaches, since 10 to 30% of relapse occurs both in maxillary and mandibular molars. The level of certainty ranged between very low and low. RCTs reporting dropout during the follow-up are in dire need.
Topics: Cephalometry; Humans; Maxilla; Molar; Open Bite; Orthodontic Anchorage Procedures; Tooth Movement Techniques
PubMed: 32888097
DOI: 10.1186/s40510-020-00328-2