摘要:

SummaryThe number of teeth needed to maintain adequate dental function in older adults is unknown. The purpose of this study was to examine the relationship between oral function and the number of opposing pairs of posterior teeth. We identified 338 subjects with complete anterior dentitions from an interview and examination survey of Ontario adults aged 50 and over; 261 had no partial denture and 77 had removable partial dentures (RPD). Oral function was measured using questions assessing chewing ability, mandibular function and socio‐psychological impact.Subjects with no partial dentures were further allocated to five groups, based on their dental status: complete dental arch (n= 69); 5–7 functional units‐pairs of opposing posterior teeth (n= 109); 3 or 4 functional units (n= 48) and 0–2 functional units (n= 35). Oral function problems increased with decreasing functional units being markedly more prevalent among the groups with 0–2 functional units. 34% of subjects in the 0–2 group reported one or more problems with chewing ability compared to 6–17% in the other groups (χ2P= 0.001 d.f. = 3).The 77 subjects who wore removable partial dentures, reported social and dental function at levels comparable to those with no dentures.From these results, there appears to be little socio‐functional need to replace lost posterior teeth with a partial denture until the person has fewer than, 3 posterior functional units. The low number of partial denture wearers limited our ability to detect a lasting benefit fr

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01119.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Summary127 Tübingen (Frialit®) implants have been clinically evaluated for a 10 year period. The implants were placed in the anterior region of the maxillae of 101 patients to replace lost incisors, cuspids and premolars. Seventy‐seven implants were placed within 3 months after loss of a natural anterior tooth, resulting in the preservation of the volume of the alveolar ridge and the contour of the surrounding soft tissues. This preservation of the volume of the alveolar ridge was due to the fact that the Tübingen implants have conical shapes and sizes, equal to those of the roots of natural teeth.The dentine‐like colour and the biological properties of the bio‐inert Al2O3implant‐material, in most of the cases was an advantage to the aesthetics of the prosthetic restorations and to the condition of the soft tissues in the permucosal area. The Tübingen implant is placed with a one‐phase technique implying special care for the temporary restorations to avoid premature loading. Also prevention of overloading the ceramic material by the fixed restoration needs special attention in the construction of posts, cores and crowns. The overall survival‐rate in this study with a mean follow‐up of 4–5 years was 87%. Patient and dentist sa

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01120.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThis case study describes the use of oxidized cellulose mesh to improve healing of periodontal defects of poor regenerative capacity. Circumferential defects with horizontal bone loss were treated by surgical exposure of the root surface followed by scaling and root planing. Prior to flap replacement, oxidized cellulose mesh was positioned in incremental layers over the defects so as to replace the lost alveolar bone. It was to act also as a barrier to the ingress of epithlial cells and gingival fibroblasts into the healing wound using the principles vof guided tissue regeneration. Healing was good, with minimal post‐operative recession. Whether regeneration of alveolar bone and periodontal ligament occurred as a result of using this technique could not be determined in this clinical case stud

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01121.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe effects of fatigue induced by 30 min of intense chewing before and after 4 weeks of 1 h daily chewing training on masticatory muscles were studied in 15 healthy subjects while eight subjects served as controls. EMG measurements in the postural position and during maximal clenching in the intercuspal position and clinical examination of the stomatognathic system were performed. Marked clinical signs of dysfunction were recorded after the first fatigue test. The severity of dysfunction diminished during the 4‐week training period and was back at the baseline level at the end of it. In the second fatigue test, after the training period, the subjects developed less dysfunction. In the control group, a mainly stable pattern was found during the observation period. There was a great variation in EMG activity during the experimental period and there were no statistically significant changes observed between any of the recordings in any of the group

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01122.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe location and the number of implants to support an overdenture is of major importance for the superstructure design. Sometimes, jaw bone anatomy or posteriorly placed implants enforce the use of an angular bar to achieve a position above the alveolar ridge. Loads on such a bar may introduce a moment on the implants which can result in high bone stresses and eventually the loss of the implants.This study on stress distribution in the bone around the implants in an edentulous mandible was performed using a three‐dimensional finite element model. One model with two implants placed just anteriorly of the mental foramen and connected with an anteriorly placed bar, following the curvature of the alveolar ridge, was compared with two other designs. First with a similar model but now without a bar and secondly with a model with four implants connected with straight bars.It is concluded that loading a bar, which is placed anteriorly of the interconnecting line between two implants, causes extremely large compressive and tensile stress concentrations in the bone around the implants. Therefore, in those cases, it is advised not to connect the implants or, in case a bar‐clip attachment is preferred, to place additional implants in the frontal reg

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01123.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThirteen dual cure luting composites were compared in function of film thickness, consistency, and working time by using the American National Standard/American Dental Association (ANS/ADA) specifications for zinc phosphate cement and direct filling resins. The effect of temperature and setting reaction on the film thickness was also evaluated for some representative products.All three clinically related properties varied widely among the products investigated. A strong linear correlation was found between film thickness and consistency. This relation is supported by the temperature dependence of film thickness of dual cure luting composites. Cooling of the material increased the consistency, resulting in a larger film thickness, while heating reduced the film thickness because of the lower consistency. However, one product with a rather short working time at room temperature occasionally exhibited a dramatically enlarged film thickness after heating, probably caused by accelerated chemical polymerization. No correlation emerged between film thickness and maximum filler size or between consistency and filler weight content. Maximum filler size and filler weight content had been measured previously in Part I of this study. Scanning electron microscope (SEM) analysis of the cured film thickness samples revealed that the largest filler particles had been crushed under the heavy load pressure during film thickness measurement. The lack of correlation between consistency and filler weight content can be explained by the multifactorial determination of the consistency.It is concluded that the great diversity in the currently available luting composites makes clear specifications with regard to the optimum composition of luting composites urgently needed. Furthermore, more adequate methods for testing the film thickness of luting composites are also required.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01124.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe electromyographic (EMG) activity of the masseter and the anterior temporalis muscles were compared between 60 healthy controls and 61 myogenous craniomandibular disorder (CMD) patients. Subjects were asked to clench at 10% and at 50% of their maximum voluntary clenching level. The effects of CMD, age and gender were statistically analysed with the use of the analysis of covariance. The correlations between EMG asymmetries and the lateral slide from the retruded contact position to the intercuspal position and the asymmetry in the number of post‐canine tooth contacts between the left and the right side were investigated.The CMD patients showed lower masseter EMG activities than the controls, whereas the anterior temporalis EMG activity was not different between the two groups. The activity index, relating the anterior temporalis EMG activity to the activity of the masseter muscles, confirmed the presence of a relatively high temporalis activity in the CMD group. No significant differences were found in the EMG asymmetries between the controls and the CMD patients. Males showed higher masticatory EMG activities than females. These gender effects were significant for the anterior temporalis at the 10% and 50% level and for the masseter muscle at the 10% level. The anterior temporalis EMG activity declined with age. No age related effects were observed in the masseter EMG. The lateral slide was larger and more prevalent in the CMD group. A significant correlation between the lateral slide and the anterior temporalis EMG was found for the CMD group at the 10% level. No correlation was found between the EMG asymmetry and the asymmetries in post‐canine tooth contacts.In conclusion: significant CMD, age and gender effects were observed in the masticatory EMG activities of a group of myogenous CMD patients and a control gr

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01125.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe aims of the study were to determine the periodontal status of the teeth in contact with removable partial dentures (RPDs) and to compare them with other teeth in the opposing arch not related to any prothesis. The periodontal status was also assessed in relation to the age of the dentures. Four hundred and twenty‐seven patients treated with RPDs from 1981 to 1986 were recalled for examination. Prior to prosthetic treatment they were given periodontal treatment and fillings when required. Initially all were given oral hygiene instructions and motivation. They were reviewed regularly only on a short‐term basis. Eighteen patients were suitable for the present study comprising of eight males and 10 females whose mean age was 41 years. The RPDs were in use from 1.5 to 8 years (mean 4.6 years). The following parameters were assessed: Plaque index (PlI), Gingival index (GI), loss of attachment (LA) and tooth mobility. The wearing of RPDs resulted in higher PlI, GI and LA compared to the controls and these differences were statistically significant. There was an increased frequency of higher PlI, GI and LA with the increase in denture age. Minor changes in tooth mobility were observed. It was concluded that the wearing of RPDs was detrimental to periodontal health in patients whose oral hygiene was less than adequ

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01126.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThis study evaluated the surface texture of three different glass ionomer restorative materials and a composite resin, polished by a new method using poly (acrylic acid) gel. Conventional polishing methods and finishing agents were compared to the proposed new procedure. Evaluations were carried out employing three techniques: profilometry, scanning electron microscopy and microhardness testing. The use of a poly(acrylic acid) gel with polishing discs gave significantly better results, and is therefore recommended for clinical applications.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01127.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryPatients with temporomandibular joint dysfunctional activity (TM dysfunction) present with a diverse spectrum of clinical signs and symptoms. The multifactorial aetiology of such disorders has been noted. Diagnostic and therapeutic problems arise due to the inadequacy of quantifying the dysfunction. TM dysfunction can affect the muscles of mastication which are responsible for mandibular movement. A pantographic reproducibility index (PRI) is available to quantitatively and qualitatively measure a subjects ability to reproduce mandibular border movements. Physical therapy modalities are used in the management of TM dysfunction. Electrogalvanic stimulation (EGS) is such an example. The effect of electrogalvanic stimulation on subjects with and without TM dysfunction was assessed by Pantronic PRI appraisal in 20 subjects. No statistically significant differences were noted. At the individual level, some changes were observed in susceptible subjects.

ISSN:0305-182X    

DOI:10.1111/j.1365-2842.1994.tb01128.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY