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The Angle Orthodontist Nov 2021To analyze the biomechanical system of anterior retraction with clear aligner therapy (CAT) with and without an anterior mini-screw and elastics.
OBJECTIVES
To analyze the biomechanical system of anterior retraction with clear aligner therapy (CAT) with and without an anterior mini-screw and elastics.
MATERIALS AND METHODS
Models including a maxillary dentition (without first premolars), maxilla, periodontal ligaments (PDLs), attachments, and aligners were constructed and imported to finite element software. Three model groups were created: (1) control (CAT alone), (2) labial elastics (CAT with elastics between the anterior mini-screw and buttons on central incisors), and (3) linguoincisal elastics (CAT with elastics between the anterior mini-screw and precision cuts on the lingual sides of the aligner). Elastic forces (0-300 g, in 50 g increments) were applied.
RESULTS
CAT alone caused lingual tipping and extrusion of the incisors. Labial elastics caused palatal root torquing and intrusion and mesial tipping of the central incisors, while linguoincisal elastics produced palatal root torquing and intrusion of both central and lateral incisors. Second premolars were intruded in all three groups, with less intrusion in the linguoincisal elastics group. For the control group, stress was concentrated on both labial and lingual root surfaces, alveolar ridge, and cervical and apical PDLs. Stress was more concentrated in the labial elastics group and less concentrated in the linguoincisal elastics group.
CONCLUSIONS
CAT produced lingual tipping and extrusion of incisors during anterior retraction. Anterior mini-screws and elastics can achieve incisor intrusion and palatal root torquing. Linguoincisal elastics are superior to labial elastics with a lower likelihood of buccal open bite. Root resorption and alveolar defects may occur in CAT, more likely for labial elastics and less likely for linguoincisal elastics.
Topics: Bone Screws; Incisor; Orthodontic Appliances, Removable; Tooth Movement Techniques; Torque
PubMed: 34061964
DOI: 10.2319/120420-982.1 -
The Angle Orthodontist Jan 2022To compare deep overbite treatment using 0.016 × 0.022 nickel-titanium lower reverse curve of Spee archwire (LRCA) or metal anterior bite turbos (ABTs). (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
To compare deep overbite treatment using 0.016 × 0.022 nickel-titanium lower reverse curve of Spee archwire (LRCA) or metal anterior bite turbos (ABTs).
MATERIALS AND METHODS
48 patients with deep overbite malocclusion were randomly allocated into two groups. Group I (age = 18.4 ± 2.8 years, overbite = 5.8 ± 0.6 mm) was treated with LRCA, while Group II (age = 18.2 ± 3.1 years, overbite = 5.2 ± 0.4 mm) was treated with ABTs bonded to the palatal surface of the upper central incisors. Two cephalograms were taken for each patient, at post-alignment stage (T1) and post-leveling stage (T2). The primary outcomes were the anteroposterior and vertical changes of the lower teeth. The secondary outcomes were the effect on upper incisor inclination and the vertical linear changes of upper teeth, to assess the sagittal and vertical skeletal changes, and to compare the duration of overbite correction.
RESULTS
42 of the 48 patients recruited completed the study (21 in each group). At T2, the lower incisors proclined more in Group I (P ≤ .001). Both lower second molars (P ≤ .001) and lower first molars (P = .001) tipped more distally, while the lower first premolar tipped more mesially, in Group I (P < .05). All cusps of both lower molars showed more extrusion in Group II (P < .05) except for the mesial cusp of lower second molars (P = .095). The duration of overbite correction was shorter using the ABTs by 1.7 months (4.85 ± 1.56 and 3.15 ± 0.93 months for Group I and Group II, respectively).
CONCLUSIONS
LRCA causes lower incisor proclination with distal tipping of lower molars, while ABTs result in lower posterior tooth extrusion.
Topics: Adolescent; Adult; Cephalometry; Humans; Incisor; Malocclusion, Angle Class II; Mandible; Overbite; Tooth Movement Techniques; Young Adult
PubMed: 34329389
DOI: 10.2319/020921-117.1 -
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 -
JDR Clinical and Translational Research Jul 2021To compare the oral microbiota of Sjögren's syndrome (SS) with that of healthy subjects (HS).
OBJECTIVE
To compare the oral microbiota of Sjögren's syndrome (SS) with that of healthy subjects (HS).
METHODS
Supragingival and subgingival biofilm samples were collected from the mesial-buccal tooth surfaces of SS patients (n = 57) and age- and sex-matched HS (n = 53). Unstimulated saliva and 8 oral tissue samples were taken using a buccal brush. Caries and periodontal measures were recorded. All supragingival samples and a subgroup of 24 SS and 28 HS subgingival samples, as well as 32 SS and 11 HS saliva and oral tissue samples, were analyzed for their content of 41 bacterial species using checkerboard DNA-DNA hybridization. Mean levels (×10 ± SEM) and percentage of DNA probe counts of each species were determined for each sample site and averaged within subjects in the 2 clinical groups. Kruskal-Wallis tests, adjusting for multiple comparisons and cluster analysis, were used for soft tissue and microbial analysis, and the Mann-Whitney test was used to compare caries and periodontal measures.
RESULTS
Mean (×10 ± SEM) total DNA probe counts in supragingival samples were significantly lower (P < 0.001) in the SS (13.3 ± .7) compared to the HS (44.1 ± 6.8) group. In supragingival samples, Veillonella parvula, Fusobacterium nucleatum ss vincenti, and Propionibacterium acnes were markedly elevated in the SS compared to the HS group in both mean (×10 ± SEM) and mean (± SEM) percentage DNA probe counts (P < 0.001). In subgingival samples of SS, V. parvula was significantly different compared to HS (P < 0.05). SS was characterized by high levels of purple and low levels of orange and red complexes. Cluster analysis of oral tissues and saliva demonstrated that the mean microbial profiles for SS patients and the HS group clustered separately. Active root caries (P < 0.003) and attachment loss were significantly higher (P < 0.029) in the SS group compared to the HS group.
CONCLUSION
These findings indicate that saliva is a major controlling factor of intraoral biofilm. V. parvula may be a unique microbial biomarker for Sjögren's syndrome.
KNOWLEDGE TRANSFER STATEMENT
The microbiome characterized for Sjögren's syndrome in salivary hypofunction is shown to be under stress and reduced. Veillonella parvula can be a possible identification of a biomarker for Sjögren's syndrome.
Topics: Colony Count, Microbial; DNA, Bacterial; Dental Plaque; Humans; Microbiota; Sjogren's Syndrome; Veillonella
PubMed: 32689841
DOI: 10.1177/2380084420940623 -
Dental Press Journal of Orthodontics 2023To measure enamel thickness at the proximal surfaces of the mandibular incisors, using micro-computed tomography (micro-CT) scans.
OBJECTIVE
To measure enamel thickness at the proximal surfaces of the mandibular incisors, using micro-computed tomography (micro-CT) scans.
MATERIAL AND METHODS
Forty-one single-rooted mandibular incisors were selected and analyzed according to anatomical characteristics, to form three groups: Group 1 - central incisors (n = 18); Group 2 - right lateral incisors (n = 10); and Group 3 - left lateral incisors (n = 13). First, enamel thickness at the proximal contact areas of the mandibular incisors was measured. Second, the mesial and distal surfaces of the lateral incisors were compared. Finally, the relationship between the tooth width and the mean enamel thickness was determined. Each tooth was scanned with a micro-CT scanner, and the image was processed with SCANCO micro-CT onboard analysis software.
RESULTS
There were no statistically significant differences in mean enamel thickness between the mesial and distal surfaces for each lateral incisor, or between contralateral lateral incisors. In all surfaces analyzed, the upper zones had statistically significantly thinner enamel (0.52 ± 0.10 mm) when compared to the middle and lower zones (0.60 ± 0.08 mm and 0.59 ± 0.08 mm, respectively). There was no correlation (r =0.07) between enamel thickness of the mandibular incisor and the tooth width.
CONCLUSIONS
The enamel thickness of the mandibular incisors is similar on the mesial and distal surfaces, with the thinnest layer located at the upper zone.
Topics: Incisor; X-Ray Microtomography; Dental Enamel; Tomography Scanners, X-Ray Computed; Mandible
PubMed: 37255131
DOI: 10.1590/2177-6709.28.2.e2321149.oar -
Maedica Jun 2023The early eruption of the first permanent molar (FPM) favors its exposure to the risk factors for dental caries specific to the mixed dentition stage of dental...
The early eruption of the first permanent molar (FPM) favors its exposure to the risk factors for dental caries specific to the mixed dentition stage of dental development. The aim of this study was to assess the prevalence and distribution pattern of FPM dental caries and of the consequences of this pathology - caries with pulp involvement in the FPM and missing FPM (FPM extraction) in a sample of Romanian children during the mixed dentition stage. To evaluate the effect of asanas in Yoga on the IOP of practicing individuals. Eighty-seven children aged between five and 13 years, who attended a private dental clinic, were enrolled in the present study. The investigations were carried out as part of the comprehensive dental examinations. Written informed consent was obtained from one of the subjects' parents prior to his/her child's participation in this research. The collected data were statistically analyzed with STATA/MP13 software using the Chi square test. The level of significance was set at p<0.05. The prevalence of FPM dental caries was 60.9%. There were statistically significant differences (p = 0.004) in the number of FPMs affected by dental caries subject in relation to age. No statistically significant differences regarding the number of FPMs affected by dental caries subject in relation to gender were found. With respect to the distribution pattern of FPM dental caries by location at tooth level, the mesial surface had the highest prevalence (in 36.8% of all investigated subjects), followed by the occlusal surface (33.3%). The prevalence of caries with pulp involvement in the FPM was 19.5% and children in the 10-11-year age group were the most affected (55.5%). There were statistically significant differences regarding the distribution pattern of caries with pulp involvement in the FPM by age (p = 0.0001). The prevalence of FPM extraction was 6.9% and, according to dental history and examination, loss of FPM was due to caries. Among children with missing FPM, five were older than the age recommended for achieving spontaneous space closure, which indicated the need for immediate intervention. Considering the results of the present study, it can be stated that FPM dental caries represents a highly prevalent pathology during the mixed dentition stage. The findings are relevant and useful for the current clinical dental practice, emphasizing the importance of caries detection and diagnosis in developing a comprehensive dental treatment plan tailored to the specific needs of pediatric patients.
PubMed: 37588835
DOI: 10.26574/maedica.2023.18.2.246 -
Epilepsy & Behavior : E&B Nov 2020The objective of the study was to examine the frequency and characteristics of ictal central apnea (ICA) in a selective cohort of patients with mesial or neocortical...
OBJECTIVE
The objective of the study was to examine the frequency and characteristics of ictal central apnea (ICA) in a selective cohort of patients with mesial or neocortical temporal lobe epilepsy (TLE) undergoing surface video-electroencephalography (EEG) and multimodal recording of cardiorespiratory parameters.
METHODS
We retrospectively screened 453 patients who underwent EEG in a single center including nasal airflow measurements, respiratory inductance plethysmography of thoracoabdominal excursions, peripheral capillary oxygen saturation, and electrocardiography. Patients with confirmed TLE subtype, either by magnetic resonance imaging (MRI) lesions limited to the temporal neocortex or mesial structures and concordant neurophysiologic data, or patients who underwent invasive explorations were included.
RESULTS
Ictal central apnea frequency and characteristics were analyzed in 41 patients with 164 seizures that had multimodal respiratory monitoring. The total occurrence of ICA in all seizures in this cohort was 79.9%. No significant difference was seen between mesial and neocortical temporal lobe seizures (79.8% and 80.0%, respectively). Ictal central apnea preceded EEG onset by 13 ± 11 s in 33.3% of seizures and was the first clinical sign by 18 ± 14 s in 48.7%. Longer ICA duration trended towards a more severe degree of hypoxemia.
CONCLUSIONS
In a selective cohort of TLE defined by MRI lesion and/or intracranial recordings, the frequency of ICA was higher than previously reported in the literature. Multimodal respiratory monitoring has localizing value and is generally well tolerated. Ictal central apnea preceded both EEG on scalp recordings as well as clinical seizure onset in a substantial number of patients. Respiratory monitoring and ICA detection is even more paramount during invasive monitoring to confirm that the recorded seizure onset is seen before the first clinical sign.
Topics: Electroencephalography; Epilepsy, Temporal Lobe; Humans; Magnetic Resonance Imaging; Retrospective Studies; Seizures; Sleep Apnea, Central
PubMed: 32916581
DOI: 10.1016/j.yebeh.2020.107434 -
Imaging Science in Dentistry Dec 2021This study introduces a standardized 2-plane approach using 8 landmarks to assess alveolar bone levels in mice using micro-computed tomography.
PURPOSE
This study introduces a standardized 2-plane approach using 8 landmarks to assess alveolar bone levels in mice using micro-computed tomography.
MATERIALS AND METHODS
Bone level differences were described as distance from the cemento-enamel junction (CEJ) to alveolar bone crest (ABC) and as percentages of vertical bone height and vertical bone loss, comparing mice infected with (Pg) to controls. Eight measurements were obtained per tooth: 2 in the sagittal plane (mesial and distal) and 6 in the coronal plane (mesiobuccal, middle-buccal, distobuccal, mesiolingual, middle-lingual, and distolingual).
RESULTS
Significant differences in the CEJ-to-ABC distance between Pg-infected mice and controls were found in the coronal plane (middle-lingual, mesiobuccal, and distolingual for the first molar; and mesiobuccal, middle-buccal, and distolingual for the second molar). In the sagittal plane, the distal measurement of the second molar was different. The middle-buccal, mesiobuccal, and distolingual sites of the first and second molars showed vertical bone loss relative to controls; the second molar middle-lingual site was also different. In the sagittal plane, the mesial sites of the first and second molars and the distal site of the second molar showed loss. Significantly different vertical bone height percentages were found for the mesial and distal sites of the second molar (sagittal plane) and the middle-lingual and distolingual sites of the first molar(coronal plane).
CONCLUSION
A reliable, standardized technique for linear periodontal assessments in mice is described. Alveolar bone loss occurred mostly on the lingual surface of the coronal plane, which is often omitted in studies.
PubMed: 34987999
DOI: 10.5624/isd.20210058 -
Romanian Journal of Morphology and... 2018The article presents aspects of crown and root morphology of the superior wisdom teeth, aiming to several parameters: size, shape crown and occlusal surface, number,...
The article presents aspects of crown and root morphology of the superior wisdom teeth, aiming to several parameters: size, shape crown and occlusal surface, number, topography and orientation of the roots in order to determine which the most common morphological types are. For this purpose, the upper wisdom teeth were collected. According to studies, the dominant form of the dental crown is parallelepipedic, the rectangular or parallelogram shape of the occlusal surface has large mesial and distal-oriented sides. The positive occlusal forms are generally poorly demarcated; cusps are less tall and rarely individualized. In half of the cases, the root is unique, voluminous, straight or with a curved distal tip.
Topics: Humans; Molar, Third
PubMed: 30534828
DOI: No ID Found -
BMC Oral Health Jun 2023This 18-month randomized clinical trial aimed to compare the effectiveness of two topical fluoride applications versus placebo control on preventing development of... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
This 18-month randomized clinical trial aimed to compare the effectiveness of two topical fluoride applications versus placebo control on preventing development of approximal caries in primary teeth.
METHODS
Preschool children were recruited if they had at least one initial approximal carious lesion at the distal surface of the canines, both approximal surfaces of the first molars, or the mesial surface of the second molars assessed from bitewing radiographs. The participants were randomly allocated into 3 intervention groups: Group 1 (placebo control), Group 2 (5% sodium fluoride [NaF] varnish), and Group 3 (38% silver diamine fluoride [SDF]). All agents were applied semiannually. Two calibrated examiners evaluated the caries development from bitewing radiographs. Caries development was recorded when the baseline sound surface or initial approximal carious lesion surface developed dentin caries (beyond the outer one-third of dentine) at the follow-up examination. The intention-to-treat approach was adopted. The Chi-square test was used to analyze the effectiveness of topical fluoride agents in preventing approximal caries development and the effect of other variables. The multi-level logistic regression analysis was performed to assess the relative effectiveness of topical fluoride agents in preventing approximal caries development at the 18-month follow-up.
RESULTS
At baseline, 190 participants with 2,685 sound or initial carries at the approximal surfaces were recruited. No differences in participant demographic backgrounds, oral health related habits, or caries experience were observed among the 3 groups (P > 0.05). After 18 months, 155 (82%) participants remained in the study. The rates of developing approximal caries in Groups 1, 2, and 3 were 24.1%, 17.1%, and 27.2%, respectively (P < 0.001, χ test). After adjusting for confounding factors and clustering effect, the multilevel logistic regression analysis showed no differences in caries development rates between the 3 groups (P > 0.05). Tooth type and the extent of a carious lesion at baseline were the significant factors for caries development.
CONCLUSION
At 18-month follow-up, after adjusting for confounding factors and clustering effect, there were no statistically significant differences in preventing of approximal caries development between the semiannual application of 5%NaF, 38%SDF, or placebo.
TRIAL REGISTRATION
The study was registered in the Thai Clinical Trials Registry under the number TCTR20190315003 on 15/03/2019.
Topics: Humans; Fluorides; Fluorides, Topical; Cariostatic Agents; Dental Caries Susceptibility; Dental Caries; Sodium Fluoride; Tooth, Deciduous
PubMed: 37268914
DOI: 10.1186/s12903-023-03045-4