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International Journal of Molecular... Jan 2021The objective of this review was to analyze the process of wear of implants leading to the shedding of titanium particles into the peri-implant hard and soft tissues.... (Review)
Review
The objective of this review was to analyze the process of wear of implants leading to the shedding of titanium particles into the peri-implant hard and soft tissues. Titanium is considered highly biocompatible with low corrosion and toxicity, but recent studies indicate that this understanding may be misleading as the properties of the material change drastically when titanium nanoparticles (NPs) are shed from implant surfaces. These NPs are immunogenic and are associated with a macrophage-mediated inflammatory response by the host. The literature discussed in this review indicates that titanium NPs may be shed from implant surfaces at the time of implant placement, under loading conditions, and during implant maintenance procedures. We also discuss the significance of the micro-gap at the implant-abutment interface and the effect of size of the titanium particles on their toxicology. These findings are significant as the titanium particles can have adverse effects on local soft and hard tissues surrounding implants, implant health and prognosis, and even the health of systemic tissues and organs.
Topics: Bite Force; Dental Implantation; Dental Implants; Humans; Metal Nanoparticles; Time Factors; Titanium; Tooth Wear; Tooth, Artificial
PubMed: 33494539
DOI: 10.3390/ijms22031067 -
The Journal of Prosthetic Dentistry Jul 2021The application of a virtual dental patient with dynamic occlusion during esthetic restoration in a digital workflow is described. An intraoral scanner, a facial...
The application of a virtual dental patient with dynamic occlusion during esthetic restoration in a digital workflow is described. An intraoral scanner, a facial scanner, a jaw motion analyzer, and cone beam computed tomography were used to transfer patient data and construct the virtual dental patient. With the aid of the virtual dental patient, predictability and accuracy can increase throughout treatment, simplifying the clinical evaluation and prosthesis adjustment with improved esthetic outcomes.
Topics: Computer-Aided Design; Cone-Beam Computed Tomography; Esthetics, Dental; Humans; Imaging, Three-Dimensional; Workflow
PubMed: 33323177
DOI: 10.1016/j.prosdent.2020.08.026 -
Cureus Nov 2023Mandibular advancement devices (MADs) remain a popular non-invasive treatment modality for the management of obstructive sleep apnea (OSA). However, the occlusal side... (Review)
Review
Mandibular advancement devices (MADs) remain a popular non-invasive treatment modality for the management of obstructive sleep apnea (OSA). However, the occlusal side effects from long-term therapy may result in poor patient compliance and patient drop-outs. Hence, knowledge of the possible side effects of these devices on occlusion is necessary. This article attempts to systematically review the evidence available in support of the possible long-term effects of mandibular advancement therapy on occlusion in adult sleep apnea patients. A detailed search was conducted for unpublished and published literature and their references in various electronic databases. A grey literature search was also performed. Studies until June 30, 2022, were selected. Randomized controlled trials, non-randomized trials, and cohort studies investigating the occlusal side effects of MADs for the treatment of snoring or OSA with a follow-up of at least four years were included. Study selection, data extraction, and risk of bias assessment were performed individually and in duplicate. The risk of bias was assessed by Cochrane tools for randomized and non-randomized studies. Fourteen studies were selected for the final qualitative analysis. The side effects reported were upper incisor retroclination, lower incisor proclination, decreased overjet and overbite, and change in the total occlusal contact area. The review concludes that long-term MAD therapy has statistically and clinically significant effects on occlusion.
PubMed: 38090465
DOI: 10.7759/cureus.48682 -
Annals of Anatomy = Anatomischer... Oct 2023Evidence regarding the etiology or effective treatments for chronic orofacial pain, the majority diagnosed as temporomandibular disorder (TMD), is limited. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Evidence regarding the etiology or effective treatments for chronic orofacial pain, the majority diagnosed as temporomandibular disorder (TMD), is limited.
PURPOSE
To investigate whether occlusal equilibration therapy (ET) and decreasing the (higher) angle of the lateral guidance on the nonworking-side leads to a reduction in chronic TMDs intensity.
METHODS
It was conducted a randomized, explanatory, single blind with blinded assessment, placebo-controlled trial with strong protection against bias involving patients with chronic TMDs. Participants were randomly assigned to receive equilibration therapy or sham therapy. ET in this study consisted of minimal invasive occlusal remodeling to obtain balanced occlusion with reduction of the steeper angle of lateral mandibular movement with respect to the Frankfort plane. The primary outcome was a change in the pain intensity score (on a 0-10 point scale, with 0 indicating no pain and 10 the worst possible pain) at month 6. Secondary outcomes include maximum unassisted mouth opening and psychological distress.
RESULTS
A total of 77 participants underwent randomization, 39 of whom received ET and 38 sham therapy. The trial was stopped early for efficacy, according to preestablished rules when 67 participants (n = 34, n = 33, respectively) had completed the analysis. At month 6, the mean unadjusted pain intensity score was 2.1 in the ET and 3.6 in the sham therapy group (adjusted mean difference, -1.54; 95% confidence interval [CI] -0.5 to -2.6; P = 0.004; ANCOVA model). The mean increase in maximum unassisted mouth opening (main secondary outcome) was significantly higher in the real therapy group (adjusted mean difference 3.1 mm, 95% CI 0.5-5.7, p = 0.02).
CONCLUSION
ET significantly reduced the intensity of facial pain associated with chronic TMDs and increased maximum unassisted mouth opening, as compared with sham therapy, over the course of 6 months. There were no serious adverse events. Funded by the Instituto de Salud Carlos III from the Ministry of Science and Innovation of the Government of Spain and European Regional Development Fund, Grant nº PI11/02507; "una manera de hacer Europa".
Topics: Humans; Single-Blind Method; Pain; Temporomandibular Joint Disorders; Treatment Outcome; Mandible
PubMed: 37302432
DOI: 10.1016/j.aanat.2023.152117 -
JPMA. the Journal of the Pakistan... Mar 2021To evaluate the parallelism of natural maxillary occlusal plane with inter-pupillary line and ala-tragus line, and to evaluate the anatomic relationship of natural...
OBJECTIVE
To evaluate the parallelism of natural maxillary occlusal plane with inter-pupillary line and ala-tragus line, and to evaluate the anatomic relationship of natural mandibular occlusal plane with retromolar pad among dentate subjects.
METHODS
The cross-sectional study was conducted from September 2017 to February 2018 at Fatima Jinnah Dental College, Karachi, and comprised front and profile photographs of subjects aged 20-28 years while holding the camper's plane against the maxillary occlusal plane. The photographs were imported in a software and an interpupillary line was drawn and the angle with Camper's plane was measured. On both profile pictures, lines were drawn from base of the ala to the superior, middle and inferior points on the tragus. The angle between ala-tragus line and Camper's plane were measured. Intra-orally, height of the mandibular occlusal plane in relation to the retromolar pad was evaluated using a stainless steel scale. Data was analysed using SPSS 23.
RESULTS
Of the 109 subjects with a mean age of 23.03±1.36 years, 76(69.72%) were females. Horizontal parallelism of occlusal plane with inter-pupillary line was observed with a mean angle of 1.17±1.27 degrees. The angle between the occlusal plane and the inferior ala-tragus line was 4.25 degrees on the right side, and 4.50 degrees on the left. Intraorally, mandibular occlusal plane coincided with the inferior 48(44%) and the middle third 48(44%) of the retromolar pad.
CONCLUSIONS
Inter-pupillary line and retromolar pad area should be used as a guide in the determination of plane of occlusion. The ala-tragus line was not found to be a reliable guide.
Topics: Adult; Cephalometry; Cross-Sectional Studies; Dental Occlusion; Female; Humans; Male; Mandible; Mouth; Young Adult
PubMed: 34057937
DOI: 10.47391/JPMA.1033 -
Journal of Dentistry Feb 2023To give an overview of the evidence on the associations between oral condition factors and masticatory performance of adults, and to evaluate the direction and level of... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To give an overview of the evidence on the associations between oral condition factors and masticatory performance of adults, and to evaluate the direction and level of the associations.
DATA/SOURCES
Medline (PubMed), Embase (Ovid) and CINAHL Plus (EBSCOhost) were searched up to May 2022 for cross-sectional studies on oral conditions and masticatory performance in adults. Methodological quality of the included studies was independently evaluated based on the Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between oral condition factors and masticatory performance were extracted. Meta-analysis was conducted on correlation coefficients.
STUDY SELECTION
Of the 8,035 records identified, 97 articles (88 studies) were included in the qualitative synthesis, and 18 studies were included in the meta-analyses. Among the oral condition factors that had associations with masticatory performance, the number of natural/remaining teeth or functional tooth pairs was reported by the largest number of studies, followed by perioral muscle status, dental prosthetic status, oral moisture status and periodontal status. Results of the meta-analyses showed that the positive association with the number of natural/remaining teeth was the strongest (pooled correlation coefficient: 0.51, 95%CI: 0.48 to 0.54), followed by the number of functional tooth pairs, maximum tongue force/pressure, while the association with the oral moisture status was the weakest.
CONCLUSIONS
Number of natural/remaining teeth and functional tooth pairs, perioral muscle status, oral moisture status, dental prosthetic status and periodontal status are the main oral condition factors influencing masticatory performance. Based on the limited evidence available, among these factors, the number of natural/remaining teeth has the strongest positive association, with a very low quality of evidence.
CLINICAL SIGNIFICANCE
This study provides valuable information on the oral condition factors associated with masticatory performance, which would be important for policymakers and clinical practitioners when deciding on the strategies for improving the masticatory performance of adults. This review highlights the need for standardization of measures and classifications of masticatory performance and oral conditions.
REGISTRATION
PROSPERO (registration number: CRD42021256824).
Topics: Humans; Adult; Bite Force; Mastication; Cross-Sectional Studies; Mouth, Edentulous
PubMed: 36563840
DOI: 10.1016/j.jdent.2022.104395 -
Clinical and Experimental Dental... Dec 2021Ear symptoms coincident with TMD symptoms have been noticed for a long time. The aim was to investigate the relationship between reported ear symptoms in TMD patients...
OBJECTIVES
Ear symptoms coincident with TMD symptoms have been noticed for a long time. The aim was to investigate the relationship between reported ear symptoms in TMD patients and different TMD symptoms, dental occlusion, oral parafunction and habits.
MATERIAL AND METHODS
Consecutive patients, ≥18 years of age and referred to a specialist clinic for orofacial pain and dysfunction during a three-month period, were considered for the study. Patients with poor general or psychiatric health were excluded. One hundred thirty-two patients were included and studied with regard to reported ear symptoms in relation to clinical dysfunction, occlusion, habits and subjective rating of their symptoms. A clinical examination was performed according to RDC/TMD and extended with occlusal factors, parafunctions and habits.
RESULTS
Ear symptoms were reported by 72% of the TMD patients, with ear fullness in 49% as the most frequent symptom. The patients with ear symptoms were significantly older and proportionally more often females. Ear symptoms were significantly correlated to the subjective index, to myalgia (p = 0.003), decreased opening capacity (p = 0.01), TMJ pain (p = 0.02), parafunctions (p = 0.007), and some occlusal factor (p = 0.018-0.003). Muscle pain on palpation was significantly associated with ear fullness, and changed hearing and sensitivity to sound, on the same side (p < 0.005).
CONCLUSIONS
Ear symptoms are frequently reported by TMD patients. Concomitant ear symptoms are associated with oral parafunction and muscle pain on palpation on the same side as the ear symptoms.
Topics: Facial Pain; Female; Habits; Humans; Myalgia; Temporomandibular Joint Disorders
PubMed: 34060246
DOI: 10.1002/cre2.457 -
International Journal of Environmental... Sep 2021Human dentin consists of a primary layer produced during tooth formation in early childhood and a second layer which first forms upon tooth eruption and continues...
Human dentin consists of a primary layer produced during tooth formation in early childhood and a second layer which first forms upon tooth eruption and continues throughout life, termed secondary dentin (SD). The effect of attrition on SD formation was considered to be confined to the area subjacent to attrition facets. However, due to a lack of three-dimensional methodologies to demonstrate the structure of the SD, this association could not be determined. Therefore, in the current study, we aimed to explore the thickening pattern of the SD in relation to the amount of occlusal and interproximal attrition. A total of 30 premolars (50-60 years of age) with varying attrition rates were evaluated using micro-computerized tomography. The results revealed thickening of the SD below the cementoenamel junction (CEJ), mostly in the mesial and distal aspects of the root ( < 0.05). The pattern of thickening under the tooth cervix, rather than in proximity to attrition facets, was consistent regardless of the attrition level. The amount of SD thickening mildly correlated with occlusal attrition ( = 0.577, < 0.05) and not with interproximal attrition. The thickening of the SD below the CEJ coincided with previous finite element models, suggesting that this area is mostly subjected to stress due to occlusal loadings. Therefore, we suggest that the SD formation might serve as a compensatory mechanism aimed to strengthen tooth structure against deflection caused by mechanical loading. Our study suggests that occlusal forces may play a significant role in SD formation.
Topics: Bicuspid; Bite Force; Child, Preschool; Dentin, Secondary; Female; Finite Element Analysis; Humans; Tooth Cervix
PubMed: 34639261
DOI: 10.3390/ijerph18199961 -
BioMed Research International 2021The wide variety of methods for recording occlusal contacts and the contradictory data on the interpretation of the obtained markings provoked us to make a comparative... (Comparative Study)
Comparative Study
INTRODUCTION
The wide variety of methods for recording occlusal contacts and the contradictory data on the interpretation of the obtained markings provoked us to make a comparative laboratory study between different occlusal indicators.
PURPOSE
Evaluation of a qualitative and quantitative method for registration of occlusal contacts in static occlusion in laboratory conditions.
MATERIALS AND METHODS
In completion of the objective, we designed an apparatus for registration of the occlusal contacts (AROC) in static occlusion which is used, corresponding to the MIP in clinical conditions. The occlusal indicators that were included in the study were articulating paper 100 , articulating foil 12 , and T-Scan Novus system with a sensor thickness of 100 . The collected primary statistical information was entered and processed with the statistical package SPSS Statistics 19.0, and the graphs were prepared using Microsoft Office 2019. We performed descriptive statistical analysis in this study. Comparisons were performed using one-way analysis of variance (ANOVA), Student's test, and Pearson coefficient method. For a significance level, < 0.05 was chosen. . With quality occlusal indicators, it is possible only to visually determine the size, number, and intensity of the marked contacts. After the statistical processing of the obtained data on the number of registered contacts, a significant difference is found in the number of contacts of certain teeth (18, 24, 25, 28, 38, 35, 34, 33, 44, 45, and 48) registered with articulating paper and articulating foil. The maximum force that is reported during the study with the T-Scan system is 93.72% and the forces in the right half of the dentition are 51.7% and in the left 48.9%. To visualize the location of the registered occlusal contacts with the system, it is intraoral to use a quality indicator and we recommend the use of articulating foil.
CONCLUSION
Based on findings from the current in vitro simulation, we can conclude that the type of occlusal indicator influences the registration of contacts, and therefore, we propose as a method of choice to achieve a balanced occlusion in clinical practice to combine the use of one conventional and one quantitative method.
Topics: Bite Force; Dental Occlusion; Humans; Image Processing, Computer-Assisted; Qualitative Research
PubMed: 34604379
DOI: 10.1155/2021/1163874 -
The Angle Orthodontist Jul 2023To determine patient perceptions and attitudes regarding posttreatment changes at least 2 years after completion of orthodontic treatment.
OBJECTIVES
To determine patient perceptions and attitudes regarding posttreatment changes at least 2 years after completion of orthodontic treatment.
MATERIALS AND METHODS
A total of 125 patients (75 females, 50 males, aged 22.93 ± 2.98 years) were enrolled at least 2 years after debonding. Participants had either vacuum-formed retainers (VFRs) or bonded retainers (BRs). Posttreatment changes were evaluated digitally by comparing tooth positions at debonding and at least 2 years after debonding. A questionnaire was used to assess patient attitudes. Retainer usage, awareness of relapse, satisfaction with their current occlusion, and whether posttreatment changes were severe enough for them to consider retreatment were investigated.
RESULTS
All patients showed some posttreatment changes in irregularity. Only 74% of patients wearing VFRs and 47.1% of patients wearing BRs were aware of posttreatment changes. Patients were more likely to notice posttreatment changes if there was an increase in mandibular irregularity of 1-3 mm. Awareness of posttreatment changes in the upper arch was higher in both groups. The majority of participants were satisfied with the results even if they noticed some minor posttreatment changes (VFR, 69.4%; BR, 76.5%). Dissatisfaction with posttreatment changes did not necessarily mean that a patient wanted retreatment.
CONCLUSIONS
A total of 26% of patients wearing VFRs and 52.9% of patients wearing BRs were unaware of posttreatment changes. Approximately half of the patients who noticed posttreatment changes were still satisfied with the result 2 years after debonding. Even patients dissatisfied with the effect of posttreatment changes do not necessarily want retreatment.
Topics: Male; Female; Humans; Orthodontic Appliance Design; Dental Occlusion; Mandible; Orthodontic Appliances, Fixed; Orthodontic Retainers; Attitude
PubMed: 36946588
DOI: 10.2319/100222-677.1