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Biomedical Journal Apr 2020Patients with cleft lip and palate could develop dentofacial deformity characterized by malocclusion, midface retrusion, midline discrepancy and asymmetry. Cleft...
Patients with cleft lip and palate could develop dentofacial deformity characterized by malocclusion, midface retrusion, midline discrepancy and asymmetry. Cleft orthognathic surgery has evolved from the simple maxillary LeFort I advancement with correction of dental malocclusion to the current model of patient-centered approach focusing on skeletofacial reconstruction using computer-assisted diagnosis and planning. Three-dimensional imaging and surgical simulation have provided valuable information for facial aesthetics and surgical feasibility. Surgery-first approach and two-jaw orthognathic surgery have gradually become prevalent replacing the conventional method. A better dentofacial outcome is achieved with reduction of the burden of care.
Topics: Humans; Cleft Lip; Cleft Palate; Computers; Dental Occlusion; Orthognathic Surgical Procedures; Patient-Centered Care; Plastic Surgery Procedures
PubMed: 32381464
DOI: 10.1016/j.bj.2019.12.008 -
The Angle Orthodontist 1991The relationship between static occlusion and functional occlusion was evaluated in 101 dental and dental hygiene students. The sample was selected from a population of...
The relationship between static occlusion and functional occlusion was evaluated in 101 dental and dental hygiene students. The sample was selected from a population of 467 students who were enrolled at one dental school during the 1987-1988 academic year based upon the following criteria: age range 18 to 32 years; caucasian race; no prior orthodontic treatment; at least 28 natural teeth present; no occlusal adjustments; and no large restorations, crowns or bridges. Fifty-two (52) of the subjects possessed "normal" static occlusion, 26 had a Class I malocclusion, 16 were found to have a Class II malocclusion, and 7 had a Class III malocclusion. The majority (i.e., 75%) of the 101 subjects possessed non-working (balancing) functional contacts. Seventy-five (75) of the subjects possessed balanced occlusion, nine had canine-protected occlusion, nine possessed group function occlusion, and eight had mixed canine-protected/group functional occlusion. This study found no statistically significant relationship between static occlusion and functional occlusion, however, there was a trend for balanced occlusion to be more often associated with "normal" (ideal) static occlusion.
Topics: Adult; Centric Relation; Cuspid; Dental Occlusion; Dental Occlusion, Balanced; Female; Humans; Male; Malocclusion; Reproducibility of Results; Tooth
PubMed: 2012324
DOI: 10.1043/0003-3219(1991)061<0057:TRBSOA>2.0.CO;2 -
IEEE Journal of Biomedical and Health... Jan 2017Partially edentulous dentition presents a challenging problem for the surgical planning of digital dental occlusion in the field of craniomaxillofacial surgery because...
Partially edentulous dentition presents a challenging problem for the surgical planning of digital dental occlusion in the field of craniomaxillofacial surgery because of the incorrect maxillomandibular distance caused by missing teeth. We propose an innovative approach called Dental Reconstruction with Symmetrical Teeth (DRST) to achieve accurate dental occlusion for the partially edentulous cases. In this DRST approach, the rigid transformation between two symmetrical teeth existing on the left and right dental model is estimated through probabilistic point registration by matching the two shapes. With the estimated transformation, the partially edentulous space can be virtually filled with the teeth in its symmetrical position. Dental alignment is performed by digital dental occlusion reestablishment algorithm with the reconstructed complete dental model. Satisfactory reconstruction and occlusion results are demonstrated with the synthetic and real partially edentulous models.
Topics: Dental Occlusion; Dentition; Humans; Imaging, Three-Dimensional; Jaw, Edentulous, Partially; Models, Dental; Orthognathic Surgical Procedures
PubMed: 26584502
DOI: 10.1109/JBHI.2015.2500191 -
IEEE Transactions on Medical Imaging Sep 2010In the field of craniomaxillofacial (CMF) surgery, surgical planning can be performed on composite 3-D models that are generated by merging a computerized tomography...
In the field of craniomaxillofacial (CMF) surgery, surgical planning can be performed on composite 3-D models that are generated by merging a computerized tomography scan with digital dental models. Digital dental models can be generated by scanning the surfaces of plaster dental models or dental impressions with a high-resolution laser scanner. During the planning process, one of the essential steps is to reestablish the dental occlusion. Unfortunately, this task is time-consuming and often inaccurate. This paper presents a new approach to automatically and efficiently reestablish dental occlusion. It includes two steps. The first step is to initially position the models based on dental curves and a point matching technique. The second step is to reposition the models to the final desired occlusion based on iterative surface-based minimum distance mapping with collision constraints. With linearization of rotation matrix, the alignment is modeled by solving quadratic programming. The simulation was completed on 12 sets of digital dental models. Two sets of dental models were partially edentulous, and another two sets have first premolar extractions for orthodontic treatment. Two validation methods were applied to the articulated models. The results show that using our method, the dental models can be successfully articulated with a small degree of deviations from the occlusion achieved with the gold-standard method.
Topics: Algorithms; Computer Simulation; Dental Occlusion; Humans; Imaging, Three-Dimensional; Mandible; Maxilla; Models, Dental; Reproducibility of Results; Tomography, X-Ray Computed; Tooth
PubMed: 20529735
DOI: 10.1109/TMI.2010.2049526 -
Medical Principles and Practice :... 2023Satisfactory masticatory function is a significant indicator of improved oral health-related quality of life in older adults, either with or without artificial teeth....
OBJECTIVES
Satisfactory masticatory function is a significant indicator of improved oral health-related quality of life in older adults, either with or without artificial teeth. The purpose of this study was to examine masticatory performance of older adults with different prosthodontic reconstructions and occlusion, as well as to compare subjective and objective assessment of chewing performance.
MATERIAL AND METHODS
This study included 100 participants aged 65 and more. The chewing function questionnaire (CFQ) with answers on the Likert scale 0-4 (0 = no difficulties; 4 = maximum difficulties) was used as an indicator of subjective masticatory assessment. The two-color chewing gum test was used as objective assessment of masticatory function (mixing ability), based on the Z-score values. Dental occlusion was assessed using functional teeth units (FTU).
RESULTS
The results obtained using the CFQ and the clinical mixing ability test are in compliance with each other (r = 0.742). A decrease in the number of natural teeth, especially posterior teeth, progressively reduced chewing ability and increased difficulties in mastication. Participants with less FTUs, or with FTUs that are a part of removable denture, had greater reduction in masticatory function compared to those with FTUs composed of natural teeth or fixed partial dentures.
CONCLUSION
This study revealed a strong positive correlation between the subjective masticatory assessment in older adults using the validated questionnaire and the objective clinical test of the mixing ability of two chewing gums. Our data on influence of the number and the type of FTU on masticatory performance will be valuable when planning prosthodontic therapy.
Topics: Humans; Aged; Quality of Life; Dental Occlusion; Tooth; Chewing Gum; Surveys and Questionnaires; Mastication
PubMed: 36682349
DOI: 10.1159/000529240 -
International Journal of Environmental... Mar 2023This study evaluated the occlusal relationships in students with bruxism, using the T-Scan III system, and their correlation with the activity of the masticatory muscles...
This study evaluated the occlusal relationships in students with bruxism, using the T-Scan III system, and their correlation with the activity of the masticatory muscles assessed through surface electromyography (sEMG). The study group was divided into two subgroups (based on self-reporting): 20 participants with possible bruxism and 20 participants without possible bruxism; all participants underwent the following evaluations: sEMG recordings using the dia-BRUXO device for masticatory muscles assessment, as well as static and dynamic occlusion using the T-SCAN III system. The analysis of the maximum intercuspidal (MI) position revealed a positive moderate association between the values of the occlusal forces in MI distributed along the two hemiarches, and the number of grinding events during daytime, which was statistically significant ( < 0.05). The analysis of protrusion movements reflected statistically significant differences between the non-working interferences and sEMG parameters specific to bruxism ( < 0.05). The analysis of laterotrusion movements indicated that participants with anterolateral guidance presented higher values of awake bruxism indexes and higher values of clenching events during nighttime. For all three mandibular movements, their duration was higher for the study group compared to the control group. Therefore, this study confirmed the utility of sEMG recordings in the bruxism diagnosis process, as well as the association between dental occlusion and bruxism.
Topics: Humans; Bruxism; Cross-Sectional Studies; Dental Occlusion; Romania; Students, Dental; Electromyography
PubMed: 36981784
DOI: 10.3390/ijerph20064877 -
Journal of Oral Rehabilitation May 2015Contacting surfaces of opposing teeth produce friction that, when altered, changes the contact force direction and/or magnitude. As friction can be influenced by several...
Contacting surfaces of opposing teeth produce friction that, when altered, changes the contact force direction and/or magnitude. As friction can be influenced by several factors, including lubrication and the contacting materials, the aim of this study was to measure the occlusal load alterations experienced by teeth with the introduction of different salivas and dental restorative materials. Pairs of molar teeth were set into occlusion with a weighted maxillary tooth mounted onto a vertical sliding assembly and the mandibular tooth supported by a load cell. The load components on the mandibular tooth were measured with three opposing pairs of dental restorative materials (plastic denture, all-ceramic and stainless steel), four (human and three artificial) salivas and 16 occlusal configurations. All lateral force component measurements were significantly different (P < 0·0001) from the dry (control) surface regardless of the crown material or occlusal configuration, while the effects of the artificial salivas compared to each other and to human saliva depended on the crown material.
Topics: Bite Force; Dental Materials; Dental Stress Analysis; Humans; In Vitro Techniques; Saliva
PubMed: 25484034
DOI: 10.1111/joor.12260 -
Journal of Oral and Maxillofacial... May 2020Methods for digital dental alignment are not readily available to automatically articulate the upper and lower jaw models. The purpose of the present study was to assess...
PURPOSE
Methods for digital dental alignment are not readily available to automatically articulate the upper and lower jaw models. The purpose of the present study was to assess the accuracy of our newly developed 3-stage automatic digital articulation approach by comparing it with the reference standard of orthodontist-articulated occlusion.
MATERIALS AND METHODS
Thirty pairs of stone dental models from double-jaw orthognathic surgery patients who had undergone 1-piece Le Fort I osteotomy were used. Two experienced orthodontists manually articulated the models to their perceived final occlusion for surgery. Each pair of models was then scanned twice-while in the orthodontist-determined occlusion and again with the upper and lower models separated and positioned randomly. The separately scanned models were automatically articulated to the final occlusion using our 3-stage algorithm, resulting in an algorithm-articulated occlusion (experimental group). The models scanned together represented the manually articulated occlusion (control group). A qualitative evaluation was completed using a 3-point categorical scale by the same orthodontists, who were unaware of the methods used to articulate the models. A quantitative evaluation was also completed to determine whether any differences were present in the midline, canine, and molar relationships between the algorithm-determined and manually articulated occlusions using repeated measures analysis of variance (ANOVA). Finally, the mean ± standard deviation values were computed to determine the differences between the 2 methods.
RESULTS
The results of the qualitative evaluation revealed that all the algorithm-articulated occlusions were as good as the manually articulated ones. The results of the repeated measures ANOVA found no statistically significant differences between the 2 methods [F(1,28) = 0.03; P = .87]. The mean differences between the 2 methods were all within 0.2 mm.
CONCLUSIONS
The results of our study have demonstrated that dental models can be accurately, reliably, and automatically articulated using our 3-stage algorithm approach, meeting the reference standard of orthodontist-articulated occlusion.
Topics: Algorithms; Dental Occlusion; Humans; Imaging, Three-Dimensional; Mandible; Maxilla; Models, Dental; Orthognathic Surgical Procedures
PubMed: 32006486
DOI: 10.1016/j.joms.2019.12.021 -
Sensors (Basel, Switzerland) Mar 2024Body biomechanics and dental occlusion are related, but this interaction is not fully elucidated. The aim of this study was to investigate the association between body...
Body biomechanics and dental occlusion are related, but this interaction is not fully elucidated. The aim of this study was to investigate the association between body posture and occlusion in patients with and without dental pathology. A cross-sectional study was carried out with 29 patients divided into a control group and a group with pathology (malocclusions). Body posture was evaluated by dynamic baropodometry, analyzing parameters such as the line of gait and the anteroposterior and lateral position of the center of pressure (CoP). Occlusion was classified radiographically according to the sagittal skeletal relationship. Results showed significant differences in mean position phase line between groups ( = 0.01-0.02), with means of 115.85 ± 16.98 mm vs. 95.74 ± 24.47 mm (left side) and 109.03 ± 18.03 mm vs. 91.23 ± 20.80 mm (right side) for controls and pathologies, respectively. The effect size was large (Cohen's d 0.97 and 0.92). There were no differences in the anteroposterior ( = 0.38) or lateral ( = 0.78) position of the CoP. In gait analysis, significant differences were observed in left (548.89 ± 127.50 N vs. 360.15 ± 125.78 N, < 0.001) and right (535.71 ± 131.57 N vs. 342.70 ± 108.40 N, < 0.001) maximum heel strength between groups. The results suggest an association between body posture and occlusion, although further studies are needed to confirm this relationship. An integrated postural and occlusal approach could optimize the diagnosis and treatment of dental patients.
Topics: Humans; Cross-Sectional Studies; Dental Occlusion; Posture; Malocclusion; Gait
PubMed: 38544184
DOI: 10.3390/s24061921 -
Clinics (Sao Paulo, Brazil) Jan 2013Force platforms are widely used to evaluate the relationship between posture and dental occlusion. This study evaluated whether force platforms are able to detect...
OBJECTIVES
Force platforms are widely used to evaluate the relationship between posture and dental occlusion. This study evaluated whether force platforms are able to detect eventual postural modifications resulting from dental occlusion.
METHOD
A total of 44 healthy volunteers who were given no information on the aim of the study underwent six postural stabilometric exams under different mandibular and visual conditions. Four parameters were considered: sway area, sway velocity, X axis displacement of the center of the foot pressure and Y axis displacement of the center of the foot pressure.
RESULTS
An analysis of variance (ANOVA) revealed the relative influence of each factor; specifically, the ocular afference significantly influenced the sway area and sway velocity parameters, and the mandibular position had only a weak influence on the sway area parameter.
CONCLUSIONS
Vision was shown to influence body posture, and a weak correlation was observed between mandibular position and body posture in healthy subjects. However, the force platform is most likely not able to clearly detect this relationship. Gnathologists must use caution when using force platform analysis to modify a therapeutic plan. The sway area seems to be the most sensitive parameter for evaluating the effect of occlusion on body posture.
Topics: Adolescent; Adult; Analysis of Variance; Dental Occlusion; Female; Humans; Male; Posture; Pressure; Reference Values; Reproducibility of Results; Vision, Ocular; Young Adult
PubMed: 23420156
DOI: 10.6061/clinics/2013(01)oa07