Category of functional tooth units in relation to the number of teeth and masticatory ability in Japanese adults

The purposes of this study were (1) to examine differences in dental status among various age groups, particularly, focusing on whether subjects retained 20 or more natural teeth, and (2) to investigate the relationship among dental status, the number and categories of functional tooth units (FTUs), and masticatory ability. A dental examination and self-administered questionnaire were conducted in a total of 2,164 residents aged 40 to 75 years who dwelt in Japan. The percentage of subjects with 20 and more natural teeth and their number of posterior teeth decreased with age. There was not much difference in the mean number of FTUs in subjects with and without 20 or more natural teeth, but those with 20 natural teeth had fewer numbers of FTUs than those with more than 20 natural teeth. The categories of the FTUs were extremely different. Subjects with 20 or more natural teeth had FTUs consisting mostly of natural to natural teeth. Subjects with 19 or fewer natural teeth had many FTUs consisting of removable prosthetic teeth. The subjective chewing ability test was significantly correlated with the number of natural teeth. Subjects could chew the higher number of test foods as the number of natural teeth increased. Not only the number of natural teeth but the categories of FTUs appear to be key factors of chewing ability. It is important to keep as many natural teeth as possible so that the person’s categories of FTUs are mainly composed of natural to natural teeth to maintain better oral function.     

老年人自觉咀嚼效能影响因素的问卷调查及分析

目的评估老年人口腔内健康存留牙的数量和位置以及患者的性别、受教育程度与自觉咀嚼效能的关系。方法 303例受试者,年龄为（67.3±5.2）岁,男性136名,女性167名。由受过培训的口腔医生对其进行口腔情况采集。对所有受试者进行自评咀嚼效能的调查问卷后计算分数。分析性别、受教育程度、口腔存留牙状况和咀嚼效能的关系。结果随着年龄的增长,咀嚼效能明显下降。无咀嚼困难的患者,口腔内至少存留有19.7颗有功能的天然牙,其中后牙区有12.8颗有功能的天然牙,至少有6.9个天然牙功能牙单位或者8.3个固定桥功能牙单位。性别和咀嚼效能无明显关系（P〉0.05）。受教育年限不超过9年的受试者比受教育年限长的受试者咀嚼效能差。结论健康存留牙的数量是影响咀嚼效级的重要因素。性别与老年人的自觉咀嚼效能无关,受教育程度与老年人的自觉咀嚼效能有关。     

The relationship between oral function and body mass index among independently living older Japanese people

PURPOSE: This study aimed to clarify the relationship between oral function and Body Mass Index (BMI) using data from independently living, relatively healthy older people. The hypothesis was that oral function is more important than dental status for healthy body weight. MATERIALS AND METHODS: The subjects were community-dwelling, independently living elderly people over 60 years of age (N = 807, 408 men and 399 women). An oral health examination, an oral and general health interview, and measurement of oral function, such as masticatory performance and occlusal force, were carried out. BMI (kg/m2) was used to measure body fat. A multiple logistic regression analysis was used for 2 outcome variables of underweight and overweight. RESULTS: Overall, 70.1% of the subjects were in the normal category of BMI (20 to 25), 13.4% were in the underweight category (< 20), and 16.5% were in the overweight category (> 25). Neither occlusal force nor masticatory performance was significantly correlated with BMI. However, when the lowest 20% of occlusal force and masticatory performance values were used as explanatory variables, multiple logistic regression analyses showed that being underweight was significantly associated with having lower masticatory performance (odds ratio = 2.0, P= .015). In addition, being overweight was significantly associated with lower occlusal force (odds ratio = 1.8, P = .013). There was no statistical difference in the underweight or overweight proportions as a function of either number of teeth or type of dentition. CONCLUSION: Based on the results of this study, occlusal force and masticatory performance, rather than number of teeth or type of dentition, may play an important role in maintaining a normal BMI in independently living older Japanese people.     

Effect of Molar Occlusal Balance on Cognitive Function in the Elderly

BackgroundElderly people with dementia, who are increasing at a rate comparable to the rate at which theelderly population is growing, are becoming a serious social problem in Korea. Therefore, the purpose of this study was to investigate the association between molar occlusal balance and cognitive function among Koreans aged 65 years and older.MethodsA total of 308 participants aged 65 years and older who attended a senior center were recruited for the study with their consent. The Korean version of the Mini-Mental State Examination (MMSE-DS) was used to assess cognitive function, and masticatory ability was measured according to the ability to chew food, the number of remaining teeth, and the self-perceived perceived masticatory function. Relative molar occlusal balance was measured using the T-scan Ⅲ system. All collected data were analysed using SPSS version 23.0.ResultsThere was a significant association between cognitive function and molar masticatory ability (P < .05). The participants with relative molar occlusal balance had a higher MMSE-DS score when compared to those with relative incision occlusal balance, adjusted for sociodemographic factors and number of remaining teeth, subjective masticatory ability, chewing ability, occlusion time, and denture use. Cognitive function was higher when relative molar occlusion was greater compared to anterior occlusion in anterior-posterior teeth balance.ConclusionsCognitive function in elderly people was higher when the relative molar occlusal balance was greater. Mastication with posterior teeth may have a more important effect on stimulation of cognitive function. Therefore, oral health care focusing on maintenance of molar teeth may be crucial for elderly persons.     

Masticatory ability and functional tooth units in Japanese adults

Summary  The purposes of this study were (i) to examine the relationship between the number of natural teeth and the number of functional tooth units in Japanese adults, (ii) to evaluate how functional tooth units relate to subjective masticatory ability and (iii) to determine the minimum number of natural teeth and functional tooth units needed to maintain adequate self-assessed chewing function. A self-administered questionnaire was given and dental examination was conducted for 2164 residents aged 40 to 75 years. Counts were made on the number of functional tooth units of natural teeth (n-functional tooth units), the sum of natural teeth and artificial teeth on implant-supported and fixed prostheses (nif-functional tooth units) and the sum of natural teeth and artificial teeth on implant-supported, fixed and removable prostheses (total-functional tooth units). The average number of natural teeth, n-functional tooth units and nif-functional tooth units decreased with age, but these were often replaced by functional tooth units from artificial teeth on removable prostheses. Total-functional tooth units in 50–59 year old people were slightly lower compared with those in other age groups. Subjects who reported that they could chew every food item on an average had 23·4 total natural teeth, 12·6 posterior natural teeth, 7·6 n-functional tooth units, 8·6 nif-functional tooth units and 10·4 total-functional tooth units, and subjects without chewing difficulties had fewer functional tooth units from removable prostheses. Maintaining 20 and more natural teeth and at least eight nif-functional tooth units is important in reducing the likelihood of self-assessed chewing difficulties.     

Validity of self‐reported tooth counts and masticatory status study of a Japanese adult population

Self‐reported measures of oral health are often used to assess oral health in populations or groups, but their validity or reliability needs repeated confirmation. The objective of this cross‐sectional study was to evaluate the validity of self‐reported tooth counts and masticatory status, using data obtained from a sample of Japanese adults. A total of 2356 adults aged 40 to 75 years participated in a questionnaire survey and a clinical oral examination from 2013 through 2016. Self‐reported measures were compared with clinically measured values. For tooth counts, mean clinical and self‐reported tooth counts in all participants were 23.68 and 23.78 teeth, and no significant difference was detected. Spearman's, Pearson's and intra‐class correlation coefficients between clinical and self‐reported tooth counts were 0.771, 0.845 and 0.843, respectively. According to the Bland‐Altman analysis, the mean difference between clinical and self‐reported tooth counts was ?0.098 (95% CI : ?0.242, 0.047). The upper limit of agreement was 6.919 (95% CI : 6.669, 7.169), and the lower limit of agreement was ?7.115 (95% CI : ?7.365, ?6.865). No significant fixed or proportional bias was observed. For masticatory status, the crude or age‐ and gender‐adjusted mean numbers of total teeth, posterior teeth and 3 kinds of functional tooth units significantly decreased with the deterioration of masticatory status. This study indicated that self‐reports were within an acceptable range of clinical measures. Therefore, self‐reports were considered valid alternatives to clinical measures to estimate tooth counts and masticatory status in a current Japanese adult population.     

后牙种植单冠修复后局部咬合变化的四年前瞻性临床研究

目的定量分析后牙种植单冠修复后4年患者口内局部力分布与咬合时间的变化规律,为种植修复体的咬合设计、调整和长期维护提供参考。方法前瞻性收集2012年12月至2013年12月于北京大学口腔医学院·口腔医院修复科行后牙种植单冠修复的患者,分别于修复后2周和3、6个月以及1、2、3、4年复查,采用咬合纸和数字化咬合分析系统检查咬合,记录种植单冠、近中邻牙和对照牙(种植单冠同颌对侧同名牙)的力百分率以及种植单冠咬合时间比(种植单冠咬合时间与牙列咬合时间的比值)。同时,通过牙线和金属邻接触检查片检查种植单冠邻接触情况,并记录种植修复相关机械并发症。采用患者自身前后对照,选取同时具备相邻随访时间点结果的患者数据,分析种植单冠、近中邻牙、对照牙力百分率以及种植单冠咬合时间比的相邻随访时间点差异;统计所有数据,比较相同时间点种植单冠与对照牙力百分率的差异。应用“对数-补对数”模型,以性别、年龄、修复时间为控制变量,分析修复体饰面瓷材料破损与否与种植单冠力百分率的相关关系。结果共纳入33例患者,其中男性16例,女性17例,年龄(42.8±12.9)岁(23.9~70.0岁);共纳入37件种植单冠,随访(38.3±15.2)个月。修复后2周至3个月种植单冠力百分率从(7.0±4.2)%显著增加至(9.9±6.8)%(P<0.05),对照牙力百分率则从(13.1±6.1)%显著减少至(11.4±5.5)%(P<0.05);修复后1、2、3年种植单冠力百分率均显著大于前一时间点(P<0.05)。修复后3和6个月种植单冠咬合时间比分别显著大于前一时间点(P<0.05),其余各时间点与前一时间点的咬合时间比差异均无统计学意义(P>0.05)。相同时间点的比较中,修复后2周种植单冠力百分率[(7.5±4.2)%]显著小于对照牙[(13.8±6.0)%](P<0.01),修复后4年种植单冠力百分率[16.7%(8.6%,32.4%)]显著大于对照牙[9.5%(4.9%,18.0%)](P<0.05);其余各时间点种植单冠与对照牙力百分率的差异均无统计学意义(P>0.05)。修复后4年37件种植单冠68个邻接触位点的邻接触丧失累计发生率为32%(22/68),修复体松动发生率为8%(3/37),饰面材料破损发生率为16%(6/37),且饰面材料破损与否与种植单冠力百分率呈弱相关关系(r=0.26,P<0.05)。结论后牙种植单冠修复后4年内,局部牙列咬合接触随时间发生变化,表现为种植单冠力的增加和咬合时间的提前。     

Influence of occlusal factors on treatment outcome: a study of 109 consecutive patients with mandibular implant-supported fixed prostheses opposing maxillary complete dentures

PURPOSE: This study was undertaken to investigate the relationship between occlusal variables and clinical and radiologic findings as well as patient response to treatment outcome in patients with mandibular implant-supported fixed prostheses opposing maxillary complete dentures. MATERIALS AND METHODS: The study group consisted of 109 consecutive patients attending for annual control. They had received their mandibular implant-supported prostheses according to the Br?nemark system on average 8 years previously (range 1 to 27 years). All patients were interviewed with standardized questions by one examiner, who also performed the clinical examination. The questions focused on the patients' opinion on masticatory and prosthetic function and problems. The clinical examination comprised occlusal and prosthetic factors and the health of the oral mucosa. RESULTS: The great majority of the patients were very satisfied with their present dental situation and masticatory function. Two thirds reported no problems with their maxillary complete dentures at all. Balanced occlusion was found bilaterally in 61%, and a further 4% had balanced function on one side. More than one third thus lacked balanced occlusion. Only about 60% had optimal occlusion, and 8% had poor occlusion according to common prosthodontic criteria. This was interpreted as a continuing impairment of the occlusion with time. The mean bone loss was 0.5 mm, according to available radiographs, for a mean observation period of 54 months. There were no or only weak correlations between the variables examined. CONCLUSION: The occlusal factors registered were of limited importance for patient satisfaction and treatment outcome recorded clinically and radiographically at follow-up examination of the actual prosthodontic rehabilitation.     

Association of masticatory performance with age, gender, number of teeth, occlusal force and salivary flow in Japanese older adults: is ageing a risk factor for masticatory dysfunction?

Objective

In general, ageing is a risk factor for sensory and motor deterioration, with the rate of decline varying amongst individuals. Concerning masticatory function, missing teeth along with oral disease seem to accelerate the dysfunction. Here, we aimed to confirm whether masticatory dysfunction by ageing is inevitable. This study investigated the effect of age, gender, number of natural teeth, occlusal force and salivary flow on the masticatory performance in a large sample of elderly adults.

Design

The study sample consisted of 1288 independently living people aged 60–84 years. Masticatory performance was determined by the comminuted particles of test food. Bilateral maximal occlusal force in the intercuspal position was measured with pressure sensitive sheets. Stimulated whole saliva was collected.

Results

Masticatory performance was significantly correlated to age, number of residual teeth, occlusal force and stimulated salivary flow rate by Pearson's correlation test. The multiple linear regression analysis showed that, with other variables controlled, masticatory performance was significantly associated with the number of residual teeth (β = 0.456, P < 0.001), occlusal force (β = 0.244, P < 0.001) and stimulated salivary flow rate (β = 0.069, P = 0.003). Age was not related to masticatory performance (β = −0.007, P = 0.753).

Conclusions

Declines in the number of residual teeth, occlusal force and salivary flow were associated with a reduction of masticatory performance in older adults. If tooth loss is not considered as an attribute of physiological ageing, then ageing by itself may not be a risk factor for masticatory dysfunction.     

Masticatory efficiency in individuals with natural dentition.

51 healthy dentate subjects aged between 20 and 60 years were evaluated with regard to their masticatory efficiency using a sieving test. A subjective evaluation of difficulty in chewing different kinds of food was also obtained by means of a questionnaire. The occlusal and restorative status were assessed using specific indices. The masticatory efficiency was shown to be lower with increasing age 20-39 years, mean = 39.8 and 40-60 years, mean = 27.1, respectively (p < 0.05). Males had a statistically significantly higher masticatory efficiency index than females. Multiple regression analysis showed that age, sex, the number of occluding teeth and the orthodontic treatment need index can predict half the variance in masticatory efficiency. It is concluded that it is more appropriate to describe masticatory efficiency with an average value for different age groups.     

The influence of occlusal surface material on peak masticatory forces using osseointegrated implant-supported prostheses.

Masticatory forces associated with porcelain and acrylic resin occlusal surfaces on osseointegrated implant-supported prostheses opposing natural teeth were studied in five healthy subjects. A three-channel electronic force transducer carrying a fixed prosthesis with either acrylic resin or porcelain occlusal surfaces and balanced articulation was used to record masticatory forces while the subjects chewed various foods. It was found that mean peak masticatory forces varied considerably from subject to subject but were consistent within each subject. No differences related to tooth material could be detected in the load rates. Forces directed away from the implants were noted in all subjects.     

Impact of masticatory performance on oral health-related quality of life for elderly Japanese

PURPOSE: This study aimed to investigate the association of masticatory performance with oral health-related quality of life in independently living elderly Japanese subjects. MATERIALS AND METHODS: The study sample consisted of 1028 independently living people over the age of 60 years. Masticatory performance was determined by the concentration of dissolved glucose obtained from test gummy jellies, which are the standardized food developed for measuring masticatory performance. The short-form Oral Health Impact Profile (OHIP-14) and Geriatric Oral Health Assessment Index (GOHAI) were used to measure the impact of oral conditions on oral health-related quality of life. RESULTS: Subjects with lower masticatory performance had significantly higher total OHIP-14 and GOHAI scores (15.0 +/- 9.0 and 14.5 +/- 9.2, respectively) than their counterparts (10.0 +/- 7.5 and 11.3 +/- 7.1, respectively) (P < .01). Logistic regression analyses showed that after controlling for age, gender, self-perceived general health, satisfaction with financial status, and number of teeth, a higher GOHAI score was significantly related to lower masticatory performance (P = .001; odds ratio: 0.56; 95% CI: 0.40 to 0.79). A higher OHIP-14 score was associated with lower masticatory performance but at a level below statistical significance (P = .096; odds ratio: 0.75; 95% CI: 0.53 to 1.05). CONCLUSION: It is suggested that masticatory performance is an important factor influencing the quality of life in independently living, relatively healthy elderly Japanese subjects.     

Effect of osseointegrated implants on the coordination of masticatory muscles: a pilot study

STATEMENT OF PROBLEM: The neuromuscular network of masticatory function is, in part, coordinated with afferent information provided by the periodontal ligament (PDL). Osseointegrated implant-supported prostheses lack this PDL-derived proprioceptive feedback mechanism. PURPOSE: This pilot study was designed to address the hypothesis that implant patients acquire different patterns of functional coordination. Patients with implant-supported prostheses were characterized in regard to masticatory muscle tenderness and fatigue as well as changes in the coordinated activities of masticatory muscles during chewing and maximal occluding force. Results were compared with those of patients with natural teeth and interpreted to assess the functional outcome of implant therapy. MATERIAL AND METHODS: Fifty-seven volunteers (25 partially edentulous patients restored with implantsupported fixed prostheses; 32 control patients) were evaluated. A comprehensive set of clinical examinations was performed, including occlusal analysis and examination of masticatory muscle and TMJ. EMG recordings of 5 volunteers from each group were further evaluated. EMG activities of the masseter and anterior temporalis were recorded during habitual chewing and voluntary maximal occluding force. RESULTS: There were essentially no differences in the clinical evaluations between volunteers in the implant and control groups and no significant alterations in the masticatory muscle coordination for habitual chewing. During the maximal occluding force measurement, EMG recordings revealed a unique masticatory muscle coordination pattern in the implant group with a tendency to activate the working and nonworking side muscles simultaneously. CONCLUSION: Patients with implant-supported prostheses appeared to be well adapted to perform habitual masticatory functions. However, during a nonhabitual function such as maximal occluding force, our pilot data revealed a less coordinated masticatory muscle activity in the implant patients.     

The Association between health-related quality of life and prosthetic status and prosthetic needs in Taiwanese adults

Summary  The objective of this study was to describe aspects of prosthetic statuses and needs and to evaluate their relationship with health-related quality of life in Taiwan. The study participants, aged 18 years and above, were recruited from a community survey, and each of the total 2469 participants received a dental examination and completed a questionnaire. Multivariable analysis was used to assess the adjusted means of health-related quality of life (SF-36) in both prosthetic status and need. The results showed that 12·6% of those aged 65 years and above were edentulous. The proportion of prosthetic need increased as age increased (39·7% to 61·3%). Multivariate analysis revealed that participants with 'removable prosthesis' had higher physical health scores than those with 'non-removable prosthesis'. The scores of mental health measurement decreased in people with need for full prostheses in relation to people without need for any prosthesis. Therefore, fulfilling prosthetic needs is not only about recovering oral masticatory function, but also concerns improvement of both physical and mental health-related quality of life.     

Occlusal force predicted cognitive decline among 70- and 80-year-old Japanese: A 3-year prospective cohort study

PurposeDementia is a growing health problem for countries with aging populations, but few effective dementia treatments are available. However, there is increasing interest in oral health as a modifiable risk factor in interventions to prevent cognitive decline. This study aimed to investigate the impact of oral health on the decline of cognitive function over 3 years among Japanese people aged 70 and 80 years.MethodsParticipants (n = 860) were community-dwelling older adults who participated in baseline and follow-up surveys (at baseline: 69–71 years n = 423; 79–81 years, n = 437). Registered dentists examined the number of teeth, number of functional teeth, number of periodontal teeth, and occlusal force. The Japanese version of the Montreal Cognitive Assessment was used to evaluate cognitive function. We also evaluated socioeconomic factors, medical history, drinking and smoking habits, physical performance, genetic factors, and C-reactive protein concentration in blood. A generalized estimating equation (GEE) was used to examine how oral health at baseline influenced cognitive decline over 3 years.ResultsThe GEE showed that the number of teeth (non-standardized coefficient: B = 0.031, p = 0.022) and occlusal force (B = 0.103, p = 0.004) at baseline were associated with cognitive function at follow-up, even after adjusting for other risk factors. Furthermore, maintaining more teeth (B = 0.009, p = 0.004) and a stronger occlusal force (B = 0.020, p = 0.040) buffered cognitive decline.ConclusionsNumber of teeth and occlusal force predict cognitive decline over 3 subsequent years in Japanese older adults aged 70 and 80 years.     

Masticatory performance in postmaxillectomy patients with edentulous maxillae fitted with obturator prostheses

PURPOSE: Oral cancer develops frequently in older populations. In Japan, the incidence of oral and pharyngeal cancer is 9,201 per year, with such tumors accounting for 1.74% of all cancers. Although obturator prostheses play an important role in the rehabilitation of postmaxillectomy patients, clinicians sometimes experience difficulty in placing obturator prostheses in edentulous maxillae, and criteria for the objective evaluation of treatment outcome have yet to be established. The present study aimed to investigate postsurgical factors influencing the masticatory performance of postmaxillectomy patients with edentulous maxillae fitted with obturator prostheses. MATERIALS AND METHODS: The extent of the hard palate defect, status of the mandibular dentition, mouth-opening distance, and maximum occlusal force were investigated, and masticatory performance was measured using a testing gummy jelly in 27 postmaxillectomy patients with edentulous maxillae fitted with obturator prostheses. The influence of these items was evaluated quantitatively, and theoretical masticatory performance for each subject was calculated using multiple-regression analysis (quantification method type 1). RESULTS: Although average masticatory performance was almost equivalent to that of healthy, independent older patients with occlusal support classified as Eichner C, considerable individual variation was noted among subjects. The order of strength of influence on masticatory performance was identified by category weight: extent of hard palate defect > status of posterior mandibular teeth > maximum occlusal force > mouth-opening distance. A relatively high correlation (R2 = 0.78, P < .01, Pearson correlation coefficient) was evident between theoretical and actual values. CONCLUSION: Masticatory performance could be predicted by evaluating postsurgical factors in patients with edentulous maxillae fitted with obturator prostheses.     

Neuromuscular coordination of masticatory muscles in subjects with two types of implant-supported prostheses

OBJECTIVES: To compare the electromyographic (EMG) characteristics of masticatory muscles in patients with fixed implant-supported prostheses and implant overdentures. MATERIAL AND METHODS: Nineteen subjects aged 45-79 years were examined. Fourteen were edentulous and had been successfully rehabilitated with (a) maxillary and mandibular implant-supported fixed prostheses (seven patients); (b) mandibular implant overdentures and maxillary complete dentures (seven patients). Five control subjects had natural dentition or single/partial (no more than two teeth) tooth or implant fixed dentures. Surface EMG of the masseter and temporal muscles was performed during unilateral gum chewing and during maximum teeth clenching. To reduce biological and instrumental noise, all values were standardized as percentage of a maximum clenching on cotton rolls. RESULTS: During clenching, temporal muscle symmetry was larger in control subjects and fixed implant-supported prosthesis patients than in overdenture patients (analysis of variance, P=0.005). No differences were found in masseter muscle symmetry or in muscular torque. Muscle activities (integrated areas of the EMG potentials over time) were significantly larger in control subjects than in implant-supported prosthesis patients (P=0.014). In both patient groups, a poor neuromuscular coordination during chewing, with altered muscular patterns, and a smaller left-right symmetry than in control subjects were found (P=0.05). No differences in masticatory frequency were found. CONCLUSION: Surface EMG analysis of clenching and chewing showed that fixed implant-supported prostheses and implant overdentures were functionally equivalent. Neuromuscular coordination during chewing was inferior to that found in subjects with natural dentition.     

Wear of resin denture teeth in partial removable dental prostheses

PurposeTo investigate occlusal wear of resin denture teeth in partial removable dental prostheses worn by partially edentulous patients.MethodsThirty patients with partial removable dental prostheses were included in the study. Thirty-two patients with complete dentures served as a reference group. Occlusal wear after two years was evaluated indirectly using gypsum casts and a three-dimensional laser-scanner device. Overall wear of complete occlusal surfaces and maximum wear of occlusal contact areas were measured. Patient and prosthesis data were analyzed using univariate and multiple linear mixed models.ResultsOverall wear of denture teeth in partial removable dental prostheses was 91 (SD 85) μm, and maximum wear of occlusal contact areas was 329 (SD 204) μm (means and standard deviations). Average and maximum wear values for teeth in complete dentures were both lower than those for teeth in partial removable dental prostheses. However, differences between wear of different types of denture did not reach statistical significance after adjustment for gender, type of tooth, dental status of the opposing jaw, and antagonist material. Statistical analysis revealed that wear was greater for denture teeth occluding with ceramic crowns and/or fixed partial dentures as antagonists.ConclusionsResin denture teeth in partial removable and complete dental prostheses are subjected to clinically important occlusal wear that might destabilize occlusion and cause further problems. Patient-related factors and dental status affect wear behavior and should be taken into consideration when treating patients with removable dentures.     

The relation between teeth loss and cognitive decline among Saudi population in the city of Riyadh: A pilot study

BackgroundTeeth are necessary for sensory input to the brain during the chewing process, but how the decrease in this sensory input, due to loss of teeth, may cause weak memory and lead to cognitive decline is not well understood. This pilot public survey aiming to assess the correlation between the number of missing teeth, periodontal disease, and cognitive skill in the city of Riyadh.Material& MethodsA multicenter cross-sectional survey, targeting geriatric population aged ≥60 years, was performed in Riyadh City, Saudi Arabia. The Montreal Cognitive Assessment (MoCA) was conducted to all participants to assess their cognitive function. Assessment of oral health status was carried out, including the number of present dentation and their periodontal status. Community periodontal-index (CPI) was used to assess the periodontal condition. The primary variables were number of missing teeth, periodontal disease and MoCA test scores. Chi-square test and Pearson’s correlation coefficients were computed and the significant P- value was set at <0.05.ResultsOf 95 participants, overall, 57 (60%) and 38 (40%) were male and female, respectively, with a mean age of 65.67 ± 6.32 years. Females showed more significant cognitive decline than males (P < 0.001). Cognitive decline was significantly high in participants with low educational level 19 (95%), unemployment 41 (79%), and lower income people 26 (79%), while being cognitive intact was significantly higher in highly educated 13 (87%), retired 21 (62%), and higher income people 28 (74%) at (P < 0.001). An advanced age and greater number of missing teeth are associated with lower MoCA test scores. No statistical significant correlation with regard to periodontal disease and MoCA test scores.ConclusionBased on the preliminary data, positive correlation was confirmed when the number of missing teeth and cognitive skill were assessed. Therefore, larger, multi-center regional surveys are needed to investigate further this relationship.     

Sense of coherence and oral health status in an adult Swedish population

Abstract

Objective . To investigate sense of coherence in relation to oral health status in an adult Swedish population in order to better understand the determinants of positive oral health-promoting behavior and differences in oral health. Material and methods . A stratified random sample of 910 individuals from Jönköping, Sweden aged 20, 30, 40, 50, 60, 70 and 80 years was obtained. The investigation used the Swedish short version of the Sense of Coherence (SOC) questionnaire comprising 13 items and a self-report questionnaire to elicit demographic information. In addition, a clinical and radiographic oral examination was performed. Results. A total of 525 individuals, 261 men and 264 women, consented to participate in the study. Bivariate analysis revealed that higher mean SOC scores were statistically significantly associated with more decayed and filled surfaces (DFS) and filled surfaces (FS), fewer decayed surfaces (DS), fewer teeth with calculus and periodontal health. Multivariate analysis showed that higher SOC scores represented a predictor of fewer occurrences of a periodontal probing pocket depth of ≥4 mm and a lower risk of plaque in different regression models. Conclusions. Higher SOC scores may be a protective determinant of plaque and periodontal disease, indicating an association between SOC and oral health.