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1.
Niger J Clin Pract ; 23(2): 258-265, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32031103

RESUMO

BACKGROUND: The Cone Beam Computed Tomography (CBCT) is currently being used as the most common diagnostic method to evaluate the bone density of the maxilla and the mandible for planning dental implant. Aim: The aim of the study is to check the quantitative alveolar bone density in complete or partial edentulous and dentulous male and female patients among Riyadh sample population in Saudi Arabia. MATERIALS AND METHODS: The study involved a cross-sectional analysis of 231 consecutive CBCT images of 231 different patients (115 males and 116 females). The scans were of Saudi National patients who were partially or completely edentulous without any bone infections in the maxilla and the mandible. The findings are presented as descriptive statistics and inferential statistics: student -t-test for two group means, ANOVA for three groups, Post-hoc LSD test for multiple comparisons, Levene statistics for testing the homogeneity of variances and a statistical significance at 5% level. RESULTS: Comparison of mean alveolar bone density in maxillae of dentulous male smokers showed a statistically significant difference for bucco-cortical plate and cancellous bone among different regions. In dentulous male nonsmokers, no significant difference was observed for maxillary regions, while in mandibular areas, a statistically significant difference was seen for buccal cortex, palatal cortex, and cancellous bone among different regions. While studying the scans of female dentulous patients, a statistically significant difference was observed in alveolar bone density for all the areas. CONCLUSION: Evaluation of bone density is an important step in treatment planning and this study was aimed to provide insight into bone density patterns of population in Riyadh, Saudi Arabia. Further similar studies in different populations can help in planning for more efficient treatment outcomes.


Assuntos
Densidade Óssea/fisiologia , Tomografia Computadorizada de Feixe Cônico/métodos , Arcada Parcialmente Edêntula/diagnóstico por imagem , Arcada Edêntula/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Adulto , Estudos Transversais , Implantes Dentários , Feminino , Humanos , Arcada Edêntula/fisiopatologia , Arcada Parcialmente Edêntula/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radiografia Panorâmica/métodos , Arábia Saudita
2.
Comput Math Methods Med ; 2019: 6839517, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31089390

RESUMO

Two-implant-retained mandibular overdentures with magnetic attachments can provide an effective treatment modality for edentulous patients. In this study, a three-dimensional finite element analysis was used to compare the biomechanical characteristics of three different types of magnetic attachments in two-implant-retained mandibular overdentures. Flat-type, dome-type, and cushion-type of the magnetic attachments were designed to retain the overdenture. Four types of load were applied to the overdenture in each model: 100 N vertical and oblique loads on the right first molar and a 100 N vertical load on the right canine and the lower incisors. The biomechanical behaviors of peri-implant bone, abutment, and mucosa were recorded. In vertical incisors, vertical right canine, and oblique molar loading condition, the flat-type group exhibited the highest levels of maximum equivalent strain/stress in the peri-implant bone. The total deformation of mucosa and the maximum equivalent strain/stress in the oblique molar loading condition are about two times as the vertical molar loading condition. These results suggested that both cushion-type and dome-type of the magnetic attachments are better choices in two-implant-retained mandibular overdentures, and oblique loading is more harmful than vertical loading.


Assuntos
Implantes Dentários/estatística & dados numéricos , Análise do Estresse Dentário/estatística & dados numéricos , Revestimento de Dentadura , Arcada Edêntula/fisiopatologia , Arcada Edêntula/cirurgia , Modelos Dentários , Fenômenos Biomecânicos , Biologia Computacional , Revestimento de Dentadura/estatística & dados numéricos , Análise de Elementos Finitos , Humanos , Imageamento Tridimensional , Magnetismo , Mandíbula/fisiopatologia , Mandíbula/cirurgia , Computação Matemática , Suporte de Carga
3.
Acta Bioeng Biomech ; 20(2): 89-100, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30220709

RESUMO

INTRODUCTION: Multifactorial aetiologies of painful temporomandibular disorders (TMD) have an impact on correct diagnosis and consequently prevent proper treatment. AIM OF THE STUDY: The aim of the study was to evaluate the effect of magnetic stimulation on electromyographic activity in temporal muscles and masseters in patients using occlusal splints. MATERIALS AND METHODS: The examined group consisted of 40 edentulous patients with TMD. The patients were examined based on Helkimo Index. Next, electromyographic activity of the temporal muscle and masseter were investigated using 8-channel surface electromyography. All patients received acrylic occlusal splints for 12 weeks. The group qualified for the study included 20 randomized patients, whose therapy was additionally carried out by extremely low-frequency magnetic fields for a period of 21 days. Following examinations were conducted after 3, 6 and 12 weeks with surface electromyography recording of the examined muscles. Patients received occlusal splint corrections using the T-Scan III system. The clinical evaluation of TMD was analysed using Helkimo index and VAS scale before and after the treatment. All the data were analysed using Statistica 12.5 PL. RESULTS: Patients with combination therapy had lower asymmetry of temporal muscle activity. CONCLUSIONS: Combination therapy using magnetic stimulation reduced intensity of pain in patients with TMD and decreased values of the Helkimo indices.


Assuntos
Arcada Edêntula/complicações , Arcada Edêntula/fisiopatologia , Magnetismo , Músculo Masseter/fisiopatologia , Dor/fisiopatologia , Músculo Temporal/fisiopatologia , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Adv Clin Exp Med ; 27(9): 1247-1252, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30024660

RESUMO

BACKGROUND: Patients with xerostomia have difficulties using dentures. Application of denture adhesives (DAs) can improve the stabilization of prostheses. OBJECTIVES: The aim of the study was to determine the retention capability of complete maxillary dentures in patients with xerostomia, determined with and without the use of prosthetic DAs. MATERIAL AND METHODS: This study evaluated the retention force of prostheses in a group of 60 patients diagnosed with xerostomia. Completely edentulous patients were classified into groups and all used the same kind of DAs during the study. The evaluation was performed 1, 3 and 6 h after application. RESULTS: All patients had poor retention of maxillary dentures without DAs. Maxillary denture retention was much better when DAs were used. The majority of the DAs used were most effective in terms of retention after 1 h. Denture adhesives in the form of glue had the best retention in this study of patients with xerostomia. CONCLUSIONS: The results of the present study revealed the impact of DAs on average retention forces in complete maxillary denture patients with xerostomia. Patients affected by a reduced secretion of saliva have difficulties using prosthetics. In some cases, such use becomes impossible because of a complete lack of retention. The application of DAs could be a solution in these cases. Denture adhesives in glue form had the best retention during the study for patients with xerostomia.


Assuntos
Adesivos/química , Retenção de Dentadura/métodos , Prótese Total Superior , Saliva/metabolismo , Glândulas Salivares Menores/fisiopatologia , Taxa Secretória/fisiologia , Xerostomia/complicações , Humanos , Arcada Edêntula/fisiopatologia , Satisfação do Paciente , Xerostomia/fisiopatologia
5.
J Contemp Dent Pract ; 19(12): 1480-1486, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30713177

RESUMO

AIM: To evaluate the satisfaction of completely edentulous patients with a different number of implants to retain removable and support the fixed prosthesis. MATERIALS AND METHODS: Fifty patients with the single edentulous ridge (maxilla or mandible) were selected for this study and divided equally into five groups. Each group contained 10 patients. Group 1: conventional complete denture (negative control group), group 2: two implants retained overdenture, group 3: three implants retained overdenture, group 4: four implants retained overdenture, group 5: fixed detachable prosthesis with five implants placed between the mental foramen. After one year from completing the treatment, the patients were requested to fill a specially designed questionnaire to assess their overall quality of life and level of satisfaction, both estheti-cally and functionally. Comparison of data between groups was performed using the Chi-square tests. The level of statistical significance was considered at p < 0.05. RESULTS: Patients treated with conventional complete denture were all unsatisfied in their masticatory function, and 80% were also unsatisfied in phonetics, while only 50% of patients were satisfied aesthetically and mentally and 70% were satisfied in social life. The addition of two or more dental implants resulted in 100% satisfaction in the variables tested. There was no statistical difference between the number of implants and supra-structure design regarding patients' satisfaction. Furthermore, implants retained overdenture and fixed detachable prosthesis design scored the same satisfactory level. CONCLUSION: The satisfaction level of the conventional complete denture in the treatment of an edentulous arch can be dramatically improved by adding dental implants and changing the design to an overdenture. Two implants with an overdenture design is a valid treatment option for the edentulous arch as well as three and four implants. Fixed detachable prosthesis did not add any further patient satisfaction when compared to implant retained overdenture. CLINICAL SIGNIFICANCE: Two implants with overdenture to treat edentulous jaw is effective as five implant fixed prosthesis.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Prótese Total , Revestimento de Dentadura , Arcada Edêntula/psicologia , Arcada Edêntula/reabilitação , Satisfação do Paciente , Humanos , Arcada Edêntula/fisiopatologia , Mastigação , Qualidade de Vida
6.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 123(5): e153-e159, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28407990

RESUMO

OBJECTIVE: The aim of this study was to compare the mandibular movements in older people with and without temporomandibular disorder (TMD) associated with rheumatoid arthritis (RA). STUDY DESIGN: Thirty partially or completely edentulous older adults (65.33 ± 4.7 years) were assigned to 2 groups: (1) with RA and TMD and (2) without RA and TMD. Chewing movements of the jaws during mastication of the test material (Optocal) and the range of mandibular movements were evaluated by using the JT-3-D kinesiographic device before and after new removable prosthesis insertion. Multiple comparisons were made with analysis of variance (ANOVA) and the Tukey-Kramer test. RESULTS: Comparisons between the 2 groups before and after new prosthesis insertion revealed that the RA and TMD group had reduced opening angles (P < .05) during chewing. After insertion of new prostheses, both groups showed increased opening and closing angles during chewing (P < .05). The mandibular range of motion results showed that patients with RA and TMD exhibited lower aperture and laterality movements (P < .05) compared with controls before and after new prosthesis insertion. However, there was an increase in aperture, lefty laterality, and protrusion values after new prosthesis insertion in both groups. CONCLUSIONS: TMD associated with RA may impair mandibular movements. Well-fitted prostheses may improve mandibular movements in older adults, especially those with RA.


Assuntos
Artrite Reumatoide/fisiopatologia , Mandíbula/fisiopatologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Idoso , Brasil , Estudos Transversais , Feminino , Humanos , Arcada Edêntula/fisiopatologia , Arcada Parcialmente Edêntula/fisiopatologia , Masculino , Mastigação/fisiologia , Amplitude de Movimento Articular/fisiologia
7.
J Forensic Sci ; 62(6): 1586-1591, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28251665

RESUMO

While changes in mandibular shape over time are not widely recognized by skeletal biologists, mandibular remodeling and associated changes in gross morphology may result from a number of causes related to mechanical stress such as antemortem tooth loss, changes in bite force, or alterations of masticatory performance. This study investigated the relationship between age-related changes and antemortem tooth loss in adult humans via dry bone measurements. This study examined 10 standard mandibular measurements as well as individual antemortem tooth loss scores using the Eichner Index from a total of 319 female and male individuals with ages ranging from 16 to 99 years. Results indicate that few mandibular measurements exhibited age-related changes, and most were affected by antemortem tooth loss.


Assuntos
Envelhecimento/fisiologia , Mandíbula/anatomia & histologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Arcada Edêntula/fisiopatologia , Masculino , Mandíbula/fisiologia , Pessoa de Meia-Idade , Perda de Dente/fisiopatologia , Adulto Jovem
8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(11): 672-677, 2017 Nov 09.
Artigo em Chinês | MEDLINE | ID: mdl-29972946

RESUMO

Objective: To evaluate the effect of different placement of mesial implants in edentulous jaws on the stress of the implant and the surrounding bone tissue by three-dimensional (3D)finite element analysis. Methods: Cone-beam CT data of mandibular edentulous patients was transferred into Mimics 17.0 and UG NX8.5 software, and three groups of 3D solid model were established: two mesial implants were implanted in the anterior region of the mandible (bilateral central incisor, lateral incisor, canine), and two distal oblique implant with 30° were implanted in the mandibular second premolar area(5 mm near the mental foramen). Set mandible 3D model with 4 implant by using UG NX8.5 software, produced 3 groups (mandible Ⅰ-Ⅲ). We took dynamic loading on models with help of software Abaqus 6.12, working side posterior teeth loading was set to 150 N and the simulation cycle was 0.875 s. The first stage: 0.000 s to 0.130 s, the lower jaw moves outward (moving toward the side of the work), with no contact between the upper and lower teeth; the second stage: 0.130 s to 0.150 s, mandibular upward, the same tooth tip of the working side were relative, the loading position were the posterior buccal tip, tongue tip; the third stage: 0.150 s to 0.260 s, the buccal slopes of buccal tips of mandibular posterior teeth glide along the lingual slopes of buccal tips of maxillary posterior teeth, the loading force was from the buccal side to the lingual side, the long axis of the tooth was 45°, loaded on the buccal slopes of buccal tips of posterior teeth; the fourth stage: 0.260 s to 0.300 s, the lingual slopes of buccal tips of mandibular posterior teeth glide along the buccal slopes of the tongue tips of maxillary posterior teeth, separate from the tip of the tooth at half the length, the loading force was from the lingual side to the buccal side, the long axis of the tooth was 45°, loaded on the lingual slopes of buccal tips of posterior teeth; the fifth stage: 0.300 s to 0.875 s, at the unloading stage, mandibular posterior teeth were separated from the maxillary teeth and returned to the intercuspal position. The loading position varied according to the mastication cycle. The stress distribution of implant and surrounding bone tissue at different stages of each model were observed. Results: From the early stage to chew occlusal contact to the end of the mastication cycle, three groups of models were displayed: the stress of distal implants was greater than that of mesial implants and the neck stress reached the maximum and gradually decreased to the root tip. The stress of distal implant bone was greater than that of mesial implant bone and the stress of distal bone of distal implant was greater than that of mesial bone of distal implant. All the stress peak showed a gradual increase, and the stress reach the maximum at the fourth stage. In the 3 models, the bone stress around the distal implant of model of the anterior implant located in the lateral incisor region was the lowest. The peak stress of cortical bone of the distal position of implant was 58.7 MPa. The bone stress around the distal implant of model of the anterior implant located in the canine region reached the maximum, and the peak stress of cortical bone of the distal position of implant was 135.6 MPa. Conclusions: When mesial implants of edentulous jaws located in the lateral incisor region, it is good for stress dispersion.


Assuntos
Implantes Dentários , Análise do Estresse Dentário/métodos , Arcada Edêntula/diagnóstico por imagem , Dente Pré-Molar , Tomografia Computadorizada de Feixe Cônico , Oclusão Dentária , Prótese Dentária Fixada por Implante , Análise de Elementos Finitos , Humanos , Incisivo , Arcada Edêntula/fisiopatologia , Mandíbula/diagnóstico por imagem , Mandíbula/fisiopatologia , Mastigação/fisiologia , Software
9.
J Oral Rehabil ; 44(3): 213-219, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27973690

RESUMO

To investigate whether there are differences in patients' denture satisfaction when an implant placed in the midline of the edentulous mandible is loaded either immediately or three months later, after second-stage surgery. One hundred and fifty-eight edentulous patients received a single implant in the midline of the mandible. After randomisation, it was loaded either immediately after implant placement (N = 81, group A) or three months later, after a submerged healing phase and a second-stage surgery (N = 77, group B). Patients' denture satisfaction aspects were assessed, using visual analogue scales (VAS), before treatment, one month after implant placement during the submerged healing phase (only group B) and one and four months after implant loading. The statistical analysis was performed using the Wilcoxon signed-rank and rank-sum tests. One month after loading, a significant improvement in comfort, function and stability of the mandibular denture could be observed in both groups (P ≤ 0·05). A slight but not significant improvement was found between one and four months after loading. Patients with second-stage surgery and delayed loading rated the stability and fit of the mandibular denture as significantly better than patients who had immediate loading. A single implant in the edentulous mandible significantly increased patients' denture satisfaction. After four months, stability and fit of the mandibular denture were considered better when a delayed loading protocol had been followed. A single mandibular implant in the edentulous mandible significantly increases patients' denture satisfaction, regardless of the loading protocol.


Assuntos
Carga Imediata em Implante Dentário/métodos , Arcada Edêntula/cirurgia , Mandíbula/cirurgia , Satisfação do Paciente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Prótese Dentária Fixada por Implante , Revestimento de Dentadura , Feminino , Alemanha , Humanos , Arcada Edêntula/fisiopatologia , Arcada Edêntula/reabilitação , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento
10.
Clin Oral Investig ; 21(2): 573-578, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27473718

RESUMO

OBJECTIVES: This study investigated chewing function in elderly individuals with Alzheimer's disease (AD) and correlated chewing function with cognitive status. MATERIALS AND METHODS: Sixteen elderly individuals with mild AD (mean age 76.7 ± 6.3 years; 8 men, 8 women) and 16 age and gender-matched healthy controls (mean age 75.23 ± 4.4 years; 8 men, 8 women) were included in this study. All volunteers wore removable prostheses: 11 were totally edentulous and five were partially edentulous in each group. Chewing function was evaluated via masticatory performance (MP) using Optocal chewable test material and a sieve fractionation method. Cognitive functioning was assessed by the Mini Mental State Exam (MMSE), administered by a trained examiner. Data were analyzed by non-paired t test and Pearson's correlation with α = 0.05. RESULTS: Compared to controls, mild AD patients had decreased MP (P < 0.01) and MMSE (P = 0.01). MP showed a moderate negative correlation with MMSE (r = -0.69). CONCLUSIONS: Mild AD was associated with impaired chewing function. CLINICAL RELEVANCE: Knowledge that mild AD has an impact on chewing is important for dental professionals in decision-making related to prosthetics and general dental treatment.


Assuntos
Doença de Alzheimer/fisiopatologia , Mastigação/fisiologia , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Arcada Edêntula/fisiopatologia , Arcada Parcialmente Edêntula/fisiopatologia , Masculino
11.
J Prosthodont Res ; 61(3): 315-323, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27989397

RESUMO

PURPOSE: This cross-sectional study analyzes how bone resorption affects the masticatory function and investigates the relation between perceived and measured masticatory function. METHODS: Thirty complete dentures wearers were divided in two groups according to mandible bone atrophy based on the classification criteria from Cawood & Howell. Retention and stability of the mandibular complete denture, masticatory performance (MP) indexes (X_50 and B) and masticatory efficiency (ME, sieves 4 and 2.8) were evaluated. Geriatric Oral Health Assessment Index (GOHAI) and Dental Impact on Daily Living (DIDL) questionnaires were completed by the patients. RESULTS: A strong correlation between bone atrophy and poor retention was found (P=0.0132). Neither masticatory performance indexes nor GOHAI and DIDL domains showed statistical differences (P>0.05) when patients were compared according to the atrophy criteria. Mandibular length showed a negative correlation with ME4, showing a positive association (R2=0.17, ß=-0.67, P=0.029). Mandibular denture retention was significantly correlated with MPB (P=0.01) and ME2.8 (P=0.01). GOHAI showed a positive association between the physical and the functional domains and ME2.8 (R2=0.17; ß=1.22; P=0.02). DIDL showed a negative association between ME4 and oral comfort domain (R2=0.16; ß=-2.94; P=0.02). CONCLUSION: Mandibular bone height does not directly affect the masticatory function and is inversely correlated with the self-perceived masticatory ability.


Assuntos
Reabsorção Óssea/fisiopatologia , Doenças Mandibulares/fisiopatologia , Mastigação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Atrofia , Reabsorção Óssea/diagnóstico por imagem , Reabsorção Óssea/patologia , Reabsorção Óssea/psicologia , Estudos Transversais , Retenção de Dentadura , Prótese Total , Feminino , Humanos , Arcada Edêntula/fisiopatologia , Arcada Edêntula/psicologia , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Doenças Mandibulares/psicologia , Pessoa de Meia-Idade , Autoimagem , Índice de Gravidade de Doença , Inquéritos e Questionários
12.
J Oral Rehabil ; 43(7): 528-33, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27084494

RESUMO

Wearing dentures has been believed to decrease the instability of the postural sway using the total length of centre of pressure (CoP) trajectory or the magnitude of its variability. However, the physical aspects of the postural sway have not been taken into account while evaluating the CoP in patients who wear dentures. The CoP fluctuations are found to show a random walk process. Therefore, changes in the random movement of CoP caused by wearing dentures should be examined by nonlinear dynamics that enables analysis of the characteristics found in the random movement. We evaluated the effect of complete denture installation on CoP sway for twenty-six edentulous patients by performing the following steps. First, we excluded subjects who did not show crossover in spectral analyses. Then, we evaluated the spectral characteristics and phase shifts of the velocities of CoP sway for the subjects who showed crossover. We found that wearing complete dentures decreased the fluctuations in the high-frequency part of the power spectral density (PSD) and the phase shift in the mediolateral direction. On the other hand, we also found that the use of complete dentures decreased the fluctuations of PSD amplitude in the anteroposterior direction. From the point of view of the kinetic energy of the musculoskeletal system, we suggested that the use of complete dentures could reduce the energy consumption for the standing posture.


Assuntos
Implantação Dentária , Arcada Edêntula/cirurgia , Acidentes por Quedas , Adaptação Fisiológica , Idoso , Fenômenos Biomecânicos , Implantação Dentária/efeitos adversos , Implantação Dentária/psicologia , Prótese Total , Feminino , Humanos , Japão , Arcada Edêntula/fisiopatologia , Arcada Edêntula/psicologia , Masculino , Equilíbrio Postural/fisiologia , Análise de Componente Principal , Dimensão Vertical
13.
Clin Implant Dent Relat Res ; 18(4): 639-48, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25891301

RESUMO

BACKGROUND: Prostheses in the edentulous maxilla affect the mucosa. PURPOSE: To evaluate mucosal alterations with implant supported fixed prostheses (FDP) and overdentures (IOD). MATERIAL AND METHODS: Patients receiving prostheses during a time period of 10 years were recruited. Maxillary mucosal conditions in relation to FDPs, IODs were analyzed. Peri-implant parameters were measured and the Oral Health Impact Profile (OHIP) was administered. RESULTS: One hundred seven patients wearing 74 IODs and 33 FDPs were identified with a total of 519 implants, the mean observation time was 6.5 ± 2.7. Cumulative implant survival was 93%. Erythema and hyperplastic tissue were identified in 71% of the IOD wearers, but were mostly absent with FDPs. The peri-implant parameters demonstrated healthy peri-implant mucosa. Medication and smoking had no effect on mucosal alteration (OR = 1.065 and 1.568). The average OHIP value was 3.73 ± 4.12. A lower value (p < 0.0048) was found for FDPs and one type of IOD. CONCLUSIONS: A rigorous maintenance program did not prevent IOD mucosal alterations in IOD wearers, but the health of the peri-implant mucosa was maintained and was comparable for all types of prostheses.


Assuntos
Prótese Dentária Fixada por Implante/efeitos adversos , Revestimento de Dentadura/efeitos adversos , Arcada Edêntula/patologia , Mucosa Bucal/patologia , Estudos de Coortes , Humanos , Arcada Edêntula/fisiopatologia , Tábuas de Vida , Maxila , Mucosa Bucal/fisiologia
14.
Int J Oral Maxillofac Implants ; 30(6): 1327-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26478980

RESUMO

PURPOSE: The purpose of this study was to examine the influence of reinforcement of an embedded cast on the strains within maxillary implant overdentures. MATERIALS AND METHODS: A maxillary edentulous model with implants placed bilaterally in the canine positions, dome-shaped copings, and experimental overdentures was fabricated. Rosette-type strain gauges were attached in the canine positions and at three points along the midline of the polished surface of the denture and connected to the sensor interface controlled by a personal computer. Experimental dentures with five different reinforcements were tested: without reinforcement; with a cast cobalt-chrome reinforcement over the residual ridge and the tops of the copings; with the same reinforcement from first molar to first molar, over the residual ridge and the tops of the copings; with the same reinforcement over the residual ridge and the sides of the copings; and with the same reinforcement from first molar to first molar, over the residual ridge and the sides of the copings. A vertical occlusal load of 49 N was applied to the first premolar and then to the first molar, and the strains were measured and compared by analysis of variance. RESULTS: In both loading situations, significantly less strain was recorded in dentures with reinforcement than in those without reinforcement. When the first premolar was loaded on dentures with and without palatal reinforcement at the first premolars, the strains on the denture with reinforcement over the tops of the copings were significantly lower than on the denture with reinforcement over the sides of the copings at the canine position. CONCLUSION: Cast reinforcement over the residual ridge and the top of copings embedded in an acrylic base reduced the strain from occlusal stress on maxillary implant overdentures.


Assuntos
Prótese Dentária Fixada por Implante , Planejamento de Dentadura , Prótese Total Superior , Revestimento de Dentadura , Resinas Acrílicas/química , Algoritmos , Força de Mordida , Ligas de Cromo/química , Dente Suporte , Implantação Dentária Endóssea/instrumentação , Implantes Dentários , Materiais Dentários/química , Bases de Dentadura , Humanos , Arcada Edêntula/fisiopatologia , Maxila/fisiopatologia , Estresse Mecânico , Propriedades de Superfície
15.
Adv Gerontol ; 28(1): 132-9, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26390624

RESUMO

This study was aimed to evaluate the functional state of statokinetic system and cervical spine in edentulous patients with concomitant somatic pathology before and three months after prosthetic dental treatment. Thirty seven edentulous patients underwent comprehensive examination including computer-assisted stabilometry. Stabilometric recordings were performed using stabilometric platform "Stabilan-01" (manufactured by special design office "Ritm", Taganrog) by means of special tests. According to the data of computer-assisted stabilometry prosthetic dental treatment leads to improvement of the functional state of statokinetic system and cervical spine in patients with concomitant somatic pathology.


Assuntos
Envelhecimento/fisiologia , Vértebras Cervicais/fisiopatologia , Arcada Edêntula/fisiopatologia , Equilíbrio Postural/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Teste da Mesa Inclinada
16.
J Craniomaxillofac Surg ; 43(5): 616-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25865491

RESUMO

OBJECTIVES: Fractures of the atrophic edentulous mandible are a rare complication that can become severe after the insertion of dental implants. This in vitro study investigated the effects of different implant settings varying in number, diameter, and length. and the influence of a fixed bar. MATERIALS AND METHODS: In biomechanical experiments on artificial mandibles, an unmodified reference group, four implant settings with two different implants, and the effect of adding a fixed bar to these settings were tested. All specimens were loaded with incisal biting forces until failure due to fracture. RESULTS: Implants weakened all specimens significantly compared with those in the reference group. Without a fixed bar, four short and thick implants showed the best results, with high significance. With a fixed bar, four long and thin implants withstood the highest loads. The addition of fixed bars reduced the differences between the implant settings. Fixed bars did not show increased stability for all groups; however, these groups showed a higher mean strength. CONCLUSIONS: Four implants with a short and thick design should be the first choice when implants are placed without a fixed bar in an atrophic mandible. With a fixed bar, four long and thin implants should be used.


Assuntos
Implantes Dentários , Planejamento de Prótese Dentária , Arcada Edêntula/fisiopatologia , Mandíbula/fisiopatologia , Atrofia , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Força de Mordida , Ligas de Cromo/química , Projeto do Implante Dentário-Pivô , Análise do Estresse Dentário/instrumentação , Humanos , Arcada Edêntula/patologia , Mandíbula/patologia , Fraturas Mandibulares/fisiopatologia , Modelos Anatômicos , Poliuretanos/química , Estresse Mecânico
18.
J Oral Maxillofac Surg ; 73(4): 683-91, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25577458

RESUMO

PURPOSE: Maxillofacial trauma resulting from falls in elderly patients is a major social and health care concern. Most of these traumatic events involve mandibular fractures. The aim of this study was to analyze stress distributions from traumatic loads applied on the symphyseal, parasymphyseal, and mandibular body regions in the elderly edentulous mandible using finite-element analysis (FEA). MATERIALS AND METHODS: Computerized tomographic analysis of an edentulous macerated human mandible of a patient approximately 65 years old was performed. The bone structure was converted into a 3-dimensional stereolithographic model, which was used to construct the computer-aided design (CAD) geometry for FEA. The mechanical properties of cortical and cancellous bone were characterized as isotropic and elastic structures, respectively, in the CAD model. The condyles were constrained to prevent free movement in the x-, y-, and z-axes during simulation. This enabled the simulation to include the presence of masticatory muscles during trauma. Three different simulations were performed. Loads of 700 N were applied perpendicular to the surface of the cortical bone in the symphyseal, parasymphyseal, and mandibular body regions. The simulation results were evaluated according to equivalent von Mises stress distributions. RESULTS: Traumatic load at the symphyseal region generated low stress levels in the mental region and high stress levels in the mandibular neck. Traumatic load at the parasymphyseal region concentrated the resulting stress close to the mental foramen. Traumatic load in the mandibular body generated extensive stress in the mandibular body, angle, and ramus. CONCLUSIONS: FEA enabled precise mapping of the stress distribution in a human elderly edentulous mandible (neck and mandibular angle) in response to 3 different traumatic load conditions. This knowledge can help guide emergency responders as they evaluate patients after a traumatic event.


Assuntos
Análise de Elementos Finitos , Arcada Edêntula/fisiopatologia , Mandíbula/fisiopatologia , Fraturas Mandibulares/fisiopatologia , Idoso , Fenômenos Biomecânicos , Simulação por Computador , Desenho Assistido por Computador , Módulo de Elasticidade , Humanos , Imageamento Tridimensional/métodos , Côndilo Mandibular/fisiopatologia , Músculos da Mastigação/fisiopatologia , Modelos Anatômicos , Modelos Biológicos , Estresse Mecânico , Tomografia Computadorizada por Raios X/métodos
19.
Comput Math Methods Med ; 2015: 943839, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26798405

RESUMO

Prosthetic rehabilitation of total edentulous jaws patients is today a common technique that clinicians approach in their daily practice. The use of dental implants for replacing missing teeth is going to be a safe technique and the implant-prosthetic materials give the possibility of having long-term clinical success. Aim of this work is to evaluate the mechanical features of three different prosthetic retention systems. By applying engineering systems of investigations like FEM and von Mises analyses, how the dental implant material holds out against the masticatory strength during the chewing cycles has been investigated. Three common dental implant overdenture retention systems have been investigated. The ball attachment system, the locator system, and the common dental abutment have been processed by Ansys Workbench 15.0 and underwent FEM and von Mises investigations. The elastic features of the materials used in the study have been taken from recent literature data. Results revealed different response for both types of device, although locator system showed better results for all conditions of loading. The data of this virtual model show all the features of different prosthetic retention systems under the masticatory load. Clinicians should find the better prosthetic solution related to the patients clinical condition in order to obtain long-term results.


Assuntos
Implantes Dentários , Revestimento de Dentadura , Arcada Edêntula/cirurgia , Fenômenos Biomecânicos , Força de Mordida , Biologia Computacional , Simulação por Computador , Planejamento de Prótese Dentária , Análise de Elementos Finitos , Humanos , Imageamento Tridimensional , Arcada Edêntula/fisiopatologia , Arcada Edêntula/reabilitação , Mandíbula/cirurgia , Teste de Materiais , Modelos Dentários
20.
J Clin Densitom ; 18(1): 50-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25439457

RESUMO

Studies have reported that masticatory function and occlusal force are low in edentulous patients, which brings about a change in the density, thickness, and alignment of bony trabeculae. However, studies that have quantitatively measured the differential cortical and medullary bone densities of the mandibular condyle in vivo remain rare. This study determined and compared the cortical and medullary bone density of the mandibular condyle in dentulous and edentulous jaws, using multidetector computed tomography (CT). Forty mandibular condyles with no clinical signs of temporomandibular disorders were investigated in 2 groups with 10 subjects (aged 50-80 yr) in each group (group I: dentulous subjects with maintained occlusion; group II: completely edentulous patients) with multidetector CT. The density of condylar cortical and medullary bone was determined by using bone density analysis algorithms available within the proprietary software. Data were analyzed statistically with the 1-way analysis of variance test (p<0.05). The mean cortical bone density of the right and left condyles of group I was 686.11±102.78 Hounsfield unit (HU) and 775.91±89.62 HU, respectively and that of group II was 531.33±289.73 HU and 648.53±294.39 HU, respectively. The mean medullary bone density of the right and left condyles was maximum in group I subjects (429.69±102.62 HU and 486.62±108.60 HU, respectively) than in group II subjects (214.89±104.37 HU and 205.36±90.91 HU, respectively) with a statistically significant decrease in the mean scores (p<0.001). Within the limitations of this study, it can be concluded that the cortical and medullary densities of the mandibular condyle are more in dentulous than the edentulous jaws.


Assuntos
Densidade Óssea , Arcada Edêntula , Côndilo Mandibular , Articulação Temporomandibular , Idoso , Dentição , Feminino , Humanos , Imageamento Tridimensional , Arcada Edêntula/diagnóstico por imagem , Arcada Edêntula/fisiopatologia , Masculino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Estatística como Assunto , Articulação Temporomandibular/diagnóstico por imagem , Articulação Temporomandibular/fisiopatologia
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