Do implant-supported dentures facilitate efficacy of eating more healthily?

Exploring the attitudes of general dental practitioners to providing dietary advice alongside oral rehabilitation for older adults

OBJECTIVE

We aimed to capture General Dental Practitioners' (GDPs) views on delivering dietary advice to older adults in combination with treatment to replace missing teeth and identify solutions to help inform the development and implementation of future dietary interventions within primary dental care.

BACKGROUND

As natural teeth are lost, older adults may need to choose softer, more manageable foods which might be of lower nutrient density. Previous research has indicated that prosthodontic rehabilitation can improve masticatory function but not the intake of nutrients, highlighting a potential need for a combined approach of oral rehabilitation and dietary counselling.

MATERIALS AND METHODS

Semi-structured telephone interviews were conducted with a purposive sampling strategy of 12 GDPs. Interviews were digitally recorded and transcribed verbatim. An iterative coding process using theme-analytic methods was used.

RESULTS

Twelve interviews were conducted with GDPs in the United Kingdom. The themes that emerged from the interviews included: the awareness of the importance of dietary advice among GDPs; the concerns GDPs had on patients' adherence to dietary advice; uncertainty over roles and responsibilities in the provision of dietary advice; and the limited time and remuneration for dietary advice in dental practice. A minor theme identified was the motivation of GDPs to implement dietary advice alongside oral rehabilitation. All reported that they were already providing dietary advice to their patients but that this was limited to caries prevention.

CONCLUSION

The GDPs interviewed expressed positive attitudes towards providing dietary advice alongside oral rehabilitation for older adults. However, a lack of confidence, awareness, time and remuneration are barriers to its provision in primary dental care. To facilitate the implementation of dietary advice alongside oral rehabilitation, clear guidance on and training in delivering dietary advice and multidisciplinary cooperation are required.

The effect of prosthetic rehabilitation with or without dietary advice on nutritional status in elderly patients: a systematic review

BACKGROUND

Elderly people frequently report tooth loss, affecting their nutritional status. There is a gap in the scientific evidence about the influence of prosthodontic rehabilitation on nutritional status.

OBJECTIVE

To investigate the influence of prosthodontic rehabilitation combinates or not with dietary advice on nutritional status in elderly patients.

METHODS

A systematic literature search was conducted in three electronic databases to identify randomized clinical trials that evaluated the effect of prosthetic rehabilitation on nutritional status in subjects aged 60 years or older, with a follow-up of at least 1 month after prosthesis rehabilitation.

RESULTS

Of the 1517 articles identified in the initial search, 12 were selected for the final review. No significant difference between the types of prosthesis were found regarding the chewing by the elderly population. Although patients who received prosthetic treatment had significant improvement in chewing ability, a consistent pattern of improvement in nutritional status was not observed when they did not receive dietary advice. In addition, the association between the condition of the dentition, the masticatory performance and nutritional change of elderly patients has been found. Studies that evaluated simultaneous complete denture treatment and simple dietary advice showed an improvement of nutrient intake in elderly patients.

CONCLUSIONS

Isolated prosthetic rehabilitation may not have the effect of exerting a change in nutritional status of edentulous elderly patients. In general, simultaneous dietary consulting and prosthetic treatment in combination may improve dietary habits, since masticatory capacity and efficiency are not the only factors that influence the nutritional status of a patient.

Development of patient-centric eating advice for complete denture wearers

BACKGROUND

Edentulous people eat less healthily, and wearing dentures impairs eating function and enjoyment.

OBJECTIVE

To apply a sequential approach to integrate scientific evidence, and patient and professional experience to co-develop intervention to support better eating with dentures.

METHODS

Focus groups, two with purposive samples of patients and two with dental professionals, explored experiences and opinions about advice on eating with complete dentures. Findings were distilled with evidence from the literature to underpinned concepts for eating interventions. User engagement informed prioritisation of ideas and led to the development of a leaflet on eating with dentures.

RESULTS

Patients receive no advice on what they can realistically expect when eating with dentures, and professionals lacked confidence to provide eating advice. Patients did not think dentists a credible provider of eating advice, feeling peer support more appropriate and offering numerous strategies for eating with dentures. Concepts for eating intervention included a patient leaflet, Web-based eating interventions, patient support blogs, waiting room videos and improved nutrition training for dental professionals. User feedback informed prioritisation of ideas, leading to the development of a leaflet on eating with dentures. Justified by the data, the leaflet focused on patient-generated tips for overcoming the functional limitations of eating with dentures, and unobtrusive healthier eating advice. Face validity with users confirmed acceptability.

CONCLUSION

A systematic and rigorous integration of scientific evidence, expert experience and patient input has developed a patient-centric, evidence-based approach to a patent leaflet on eating with dentures that, based on initial face validity, is likely to be well received.

The impact of implant-retained overdentures on type-2 diabetic and non-diabetic edentulous patients: Satisfaction and quality of life in a prospective cohort study

OBJECTIVES

To evaluate the benefits of implant therapy for patients with diabetes, we compared (i) healthy, (ii) well controlled T2DM and (iii) poorly controlled T2DM patients, in terms of oral health-related quality of life (OHRQoL) and satisfaction with mandibular 2-implant overdentures over 12 months following restoration.

MATERIALS AND METHODS

This single-center, prospective, cohort study recruited 165 edentulous adults (HbA1c<12%) to receive two endosseous implants in the anterior mandible to support mandibular overdentures. Participants were enrolled as having T2DM or not, with T2DM participants divided according to HbA1c into well-controlled (<8.1%) and poorly controlled (≥ 8.1%) groups. Participants provided responses to the OHIP-20 (OHRQoL) and the McGill Denture Satisfaction Questionnaire, before implant therapy and 6 and 12 months after overdenture insertion using Locator attachments. HbA1c was measured at the same time points. The effect of groups and time was verified using generalized estimating equations (α=0.025).

RESULTS

At 12 months, 137 participants provided responses. The two diabetes groups showed improvements in OHRQoL to the same extent as the non-diabetic control group at both 6 and 12 months. Patient satisfaction showed similar improvements with no between-group differences and similar increases identified at 6 and 12 months. HbA1c was not affected by time or groups.

CONCLUSIONS

Dental implant therapy provided significant improvements in patient-perceived benefits of mandibular two-implant overdentures for T2DM individuals, which are similar to those found for healthy edentulous individuals. Importantly, those benefits extend to those individuals with poorly controlled glycaemia. The addition of 2-implant supported mandibular overdentures did not affect glycaemic status over 12 months following insertion.

CLINICAL SIGNIFICANCE

As risks for implant therapy relative to glycaemic status are better understood, this study documents that implant therapy may offer important benefits in QoL for T2DM patients independent of glycaemic status.

Eating Advice for People Who Wear Dentures: A Scoping Review

Objective: A scoping review of available advice to address eating problems experienced by people who wear dentures was conducted in accordance with the PRISMA statement. The objective was to identify and map type, volume, and content of the available eating advice. Methods: Medline, CINAHL, and grey literature databases and Google were searched. Relevant content pertaining to study type, peer-review vs. grey literature, country of origin, advice content, and methods to evaluate effectiveness was mapped. Results: Of the 4591 records identified from peer-reviewed literature, 56 full papers underwent duplicate screening, resulting in 26 papers (from Germany (n = 1), Europe (n = 1), India (n = 2), Japan (n = 7), UK (n = 6), USA (n = 6), or other (n = 3)) being included in the review. These yielded 18 different items of relevant eating advice. Of the 258 screened websites, 63 were included, yielding 30 different items of eating advice. The most-cited advice was to eat soft food and avoid hard and sticky food, cut food into bite-sized pieces, and chew on both sides of the mouth and chew slowly and thoroughly. The identified advice was not supported by reference to peer-reviewed evidence. Advice included some conflicting messages and some advice was non-compliant with authoritative nutritional advice (e.g., avoid red meat, take a vitamin supplement). Conclusion: There is support for providing eating advice at the time of denture provision. A broad range of advice based on clinical experience to support people who wear dentures to overcome the functional limitations exists. However, the efficacy of this advice in improving diet and eating experience has not been tested.

Do implant-supported prostheses affect bioavailability of nutrients of complete and partially edentulous patients? A systematic review with meta-analysis

BACKGROUND & AIMS

Debate still exists about the impact of dental implant-supported prostheses on nutritional status of partially and complete edentulous patients. This review aims to answer the focused question: "Do complete and partial edentulous patients, using implant-supported prostheses, present better nutritional and masticatory functions when compared to those using conventional rehabilitations?". A possible cause-effect relationship between masticatory improvements and nutritional gain was also evaluated.

METHODS

Literature search included 6 databases (PubMed/Medline, Embase, LILACS, Scopus, Web of Science, and The Cochrane Library - CENTRAL), grey literature (Google Scholar, Proquest Dissertations and Thesis and Open Grey databases) and manual search (last update June 2020), without language, publication time and follow-up restrictions. We included only studies evaluating both masticatory and nutritional outcomes. The PICO question comprised complete and partial edentulous patients (Population), submitted to implant-supported prostheses (Intervention), in comparison to conventional dental prosthetic rehabilitation, evaluating masticatory function and nutrition parameters (outcomes). Risk of bias was assessed by using Cochrane Collaboration's tool (randomized clinical trials), Joanna Briggs Institute critical appraisal checklist (paired clinical trials), and Meta-Analysis of Statistics Assessment and Review Instrument" (JBI - MAStARI) critical appraisal tools (cohort studies). All meta-analyses were conducted at 5% level of significance. This report followed the PRISMA guidelines. (Review registration PROSPERO - CRD42019135744).

RESULTS

We identified 1199 articles while searching databases. Fourteen articles met eligibility criteria, including 817 prostheses installed in 660 patients (mean age = 66.8 years-old). Patients wearing implant overdentures (IOD) presented better masticatory function in comparison to conventional complete denture (CD) wearers (p < 0.05). However, bioavailability of several nutrients remained within the same range, except for serum folate that was lower in IOD patients after 6 (mean difference 3.51 nmol/L; p = 0.01) and 12 months of rehabilitation (mean difference 3.69 nmol/L; p = 0.003). When comparing the effects of CD and IOD rehabilitations along time (for the same patient), serum albumin and vitamin B12 levels also decreased for both groups after 12 months-follow-up, but still within the reference range. The additional retention of the implants did not interfere in body weight, but reduced the risk of malnutrition (using the Mini Nutritional Assessment). Implant-supported partial prostheses also improved mastication in comparison to the conventional ones, increasing short-term daily intake of carbohydrates, protein, calcium, fiber, and iron, whereas decreasing the consumption of cholesterol. However, no long-term changes on bioavailability of most nutrients were observed, expect for a slight increase in ferritin and cholinesterase, and a small reduction in folate and Vitamin A.

CONCLUSION

Current evidence indicates significant masticatory improvements for dental fixed implant-supported prostheses in comparison to conventional removable prostheses. However, bioavailability remained stable for most of the nutrients, especially for complete edentulous patients. These results indicate the importance of a multidisciplinary approach during oral rehabilitation (nutrient specialist), in order to enhance food choices and promote health benefits to the patients.

Semi-powered exoskeleton that regulates the muscular activity of jaw movement for oral functional rehabilitation/training

The sequential oral functions of mastication and swallowing are well tuned in humans. To prevent oral hypofunction as a risk factor for systemic frailty by oral motor training, semi-powered exoskeleton was developed and evaluated its loading/assist effects by monitoring electromyography signals and saliva secretion in healthy persons. The actuator of the driving unit combined mechanical and powered mechanics and was driven alternatively by an unpowered stainless-steel spring system for jaw-opening training by loading and a powered shape-memory alloy spring system to assist jaw closing. Sequential device movement was controlled by two electronic circuits with two magnetic switching systems to match human jaw movement. This exoskeleton realized a 25% increase of jaw-opening muscular activity for training, 15% saving of jaw-closing muscular activity for assistance, and 15% enhancement of saliva secretion, which could contribute to the prevention of oral frailty by maintenance and strengthening of oral function in the upcoming super-aging society.

Clinical and academic recommendations for primary dental care prosthodontics

Prosthodontic practice includes a large proportion of dental care provision, mostly undertaken in primary dental care (PDC) in the UK. However, there is limited research evidence in prosthodontic practice, necessary to tackle key questions to improve oral and dental health. In addition, many overarching challenges exist within the NHS system relevant to prosthodontics. For example, demands on healthcare services from increasing patient expectations, the ever-ageing and growing population, risks of litigation, availability of appropriate care, difficulties with access to care, rapidly emerging treatments and technologies, and ongoing needs for education. This article develops clinical and academic recommendations to improve oral health improvements in PDC prosthodontics, further to recommendations determined by the James Lind Alliance, a non-profit making initiative to tackle treatment 'uncertainties' (http://www.jla.nihr.ac.uk/), and the overarching challenges, which are mentioned above. Considerable clinical and academic author experiences from primary, secondary and tertiary care as well as education and research in prosthodontics are employed. We consider management of networks involving patients, carers, healthcare professionals, industry and academics, in order to increase access to improve oral and general health and help drive dental research, education and communication. We investigate how to manage dental disease and intervene to improve the longevity of restorations and the dentition. Finally, we review how rapidly developing digital technologies can best be utilised, in conjunction with industry, in order to improve oral health.

Sensorial Ability, Mastication and Nutrition of Single-Implant Overdentures Wearers

Abstract The use of two-implant overdentures improves mastication of edentulous elderly patients. However, little is known about the effects of single-implant overdentures (SIO) on oral perception and masticatory function in such elders. This study compared the effects of conventional complete dentures (CD) and SIO on the oral sensorimotor ability (OSA), masticatory function, and nutritional intake of elderly people with residual alveolar mandibular height classified as Class III or IV according to the American College of Prosthodontics. Twelve elders first received new conventional CD, which were later converted to SIO. All variables were evaluated after use of each prosthesis for 2 months. To evaluate OSA, elders closed their eyes and orally identified test pieces prepared from raw carrots. A kinesiographic device was used to measure chewing movements during mastication of a test material (Optocal). Masticatory performance (MP) was determined with the sieving method, and a 3-day food diary verified nutrient intake based on a standard Brazilian Food Composition Table. Data were analyzed using the Wilcoxon signed rank test and Student’s paired t test (P < 0.05). OSA results did not differ according to prosthesis type. However, opening and closing velocities during chewing and MP increased after SIO insertion (P < 0.05). Although no difference was observed in the intake of most nutrients, sodium ingestion decreased after SIO insertion (P < 0.05). SIO use had no effect on OSA, but significantly improved mastication and sodium intake of elders with decreased residual ridges height (Brazilian Registry of Clinical Trials #RBR-3kgttj).

Effect of implant-supported mandibular overdentures versus reline on masticatory performance and salivary flow rates in very old adults-A randomized clinical trial

PURPOSE

To compare the masticatory efficiency (ME), maximum voluntary bite force (MBF), masseter muscle thickness (MMT), and salivary flow rates (SFR) in completely edentulous dependent elders treated either with a conversion of their existing mandibular complete removable dental prostheses (CRDPs) into a two-implant overdenture (IOD) or a conventional reline of the CRDP.

MATERIAL AND METHODS

Participants were randomly allocated into intervention (IG) and control (CG) groups. The IG received two implants in the mandibular canine regions, and their CRDPs were transformed into IODs. The CG received a conventional reline of their mandibular CRDPs. Outcomes were recorded at each recall visit (baseline, immediately, 3 months, 12 months after intervention, and subsequently on an annual basis). Statistical analyses used mixed linear regression models (level of significance: p < 0.05).

RESULTS

The IG comprised 16 participants (age = 85.0 ± 6.2 years), while the CG comprised 16 (age = 84.8 ± 5.4 years), with a mean follow-up of 2.7 ± 2.2 years (range: 3 months-7 years). A significant increase of MBF in the IG was observed with an overall gain of 80 N (p < 0.001) compared with the reline group. There were no significant long-term changes in SFR, MMT, or ME within/between groups.

CONCLUSION

Since dependent elders with mandibular IODs present a significant gain in MBF, but no relative increase in SFR, MMT, and ME, it seems that this increased capacity of MBF is not exploited by the elders during their habitual chewing.

The Association of Poor Oral Health Parameters with Malnutrition in Older Adults: A Review Considering the Potential Implications for Cognitive Impairment

Poor dental status and chewing deficiencies have been associated with cognitive decline. Altered dietary habits and malnutrition have been suggested as linking mechanisms. The aim of the present review was thus to investigate if poor oral health, and in particular tooth loss and impaired masticatory function, may affect dietary selection and nutritional intake in older adults, and moreover, to assess if prosthodontic dental care may improve nutritional status. Extensive tooth loss may impair masticatory function. Several studies in older populations have shown that severe tooth loss and masticatory impairment are associated with limited consumption of various food types (especially fruits and vegetables), increased consumption of sugary and easy-to-chew foods, and lower dietary intake of fibre and vitamins. However, these findings are not consistently reported, due to methodological variation among studies, potential adverse causalities, and the multifactorial nature of food choices. On the other hand, a few interventional studies revealed that prosthetic rehabilitation of missing teeth, when accompanied by dietary counselling, may improve dietary habits and nutritional intake. Further research is required to improve current knowledge of these associations. Under the limitations of the current study, a functional dental arch of natural or artificial teeth is important for maintaining adequate chewing efficiency and ability, but this only partly contributes to food choices and nutritional status. The multifactorial nature of food choices necessitates the interprofessional collaboration of dental professionals, dietetics practitioners, and primary care providers to improve dietary habits and nutritional intake.

Combined effects of new complete denture fabrication and simplified dietary advice on nutrient intake in edentulous elderly patients for 6 months

OBJECTIVE

The aim was to evaluate the combined effects of a new complete denture fabrication and simple dietary advice (using unique pamphlets) by dentists on nutrient intake in edentulous elderly patients.

MATERIALS AND METHODS

A randomized controlled trial was performed on edentulous elderly patients who were randomly allocated to either an intervention or a control group. The intervention group received a new complete denture and simple dietary advice, whereas the control group received a new complete denture and denture care advice. The outcomes of this trial (nutrient intakes) were calculated using a brief-type self-administered diet history questionnaire (BDHQ) and assessed at three time points (pretreatment and 3 and 6 months post-treatment).

RESULTS

At 3 months post-treatment, the intake of several nutrients such as proteins (p = 0.004), magnesium (p < 0.001), and vitamin B1 (p = 0.014) was significantly higher in the intervention group than the control group, whereas at 6 months post-treatment, plant protein (p = 0.028) intake was significantly higher in the intervention group than the control group. On the contrary, animal protein (p = 0.049) and vitamin B12 (p = 0.028) intakes were significantly higher in the control group.

CONCLUSIONS

New complete denture fabrication with simple dietary advice might improve nutrient intake in elderly edentulous patients; however, the effect is probably short term.

CLINICAL SIGNIFICANCE

New complete denture fabrication along with simple dietary advice by dentists might improve nutrient intake in edentulous elderly patients. Therefore, regular use of these interventions in the dental setting might have long-term effects on nutrient intake in elderly edentulous patients.

TRIAL REGISTRATION

UMIN-CTR Clinical Trial, unique trial number: UMIN000017879.

Relationship between masticatory function and frailty in community-dwelling Japanese elderly

BACKGROUND

Frailty likely results in impaired functioning, and frail individuals requiring long-term care have recently attracted the attention of researchers. In the oral health field, the number of elderly individuals who require intervention for retaining occlusion has been increasing, as has the number of remaining teeth and required prosthetic treatment. Additionally, the number of elderly with reduced masticatory function has also been increasing, and frailty is a suspected factor.

AIMS

The aim of this study is to clarify the relationship between frailty and masticatory function decline.

DESIGN

A cross-sectional study.

METHODS

A total of 747 participants (total mean age 73.6 ± 5.8 years old) underwent a comprehensive examination at the Tokyo Metropolitan Institute of Gerontology. Three masticatory functions were evaluated: maximum occlusal force, mixing ability, and self-reported chewing ability. Frailty was determined using all 25 questions of the Basic checklist developed by the Japanese Ministry of Health, Labour and Welfare, following the method reported by Satake et al. RESULTS: Binomial logistic analysis clarified the relationship between frailty and evaluation of each of the three masticatory functions. Significant correlations of pre-frailty or frailty with maximum occlusal force, mixing ability, and subjective chewing ability were observed.

CONCLUSION

All three masticatory functions (maximum occlusal force, mixing ability, and self-reported chewing ability) were associated with pre-frailty or frailty in community-dwelling Japanese elderly.

Are UK graduates equipped with the skill set required to meet the demands of the UK's edentulous population?

As the UK witnesses a decline in the number of edentulous adults, there is a simultaneous reduction in the number of cases available to undergraduate dental students for the teaching of complete dentures. When edentulous adults are unable to function with conventional complete dentures, particularly pertaining to the mandibular denture, an implant-supported mandibular overdenture has been evidenced as the gold standard for edentulous patients. The evidence in favour of mandibular implant-supported overdentures is one of the most robust evidence bases for any clinical treatment and similarly it has been shown that undergraduate students are equally as capable in the provision of implant-supported overdentures as experienced prosthodontists. Yet there appears to be a disparity in the General Dental Council's undergraduate learning outcomes pertaining to care for edentulous adults. Furthermore, the UK seems to be falling behind in this respect in comparison to our European, American and Australian colleagues. This review looks at the evidence for the provision of implant-supported overdentures in the setting of the undergraduate dental curriculum, the potential barriers within this teaching forum and how well prepared UK undergraduates are for the clinical management of edentulous patients in the future.

Combined effect of new complete dentures and simple dietary advice on nutritional status in edentulous patients: study protocol for a randomized controlled trial

Background

Individuals who are edentulous have a lower intake of fruit, vegetables, fiber, and protein compared with their dentate counterparts because tooth loss is accompanied by a decrease in ability to chew. Whether or not a combination of prosthetic rehabilitation and simple dietary advice produces improvement in dietary intake among edentulous persons is unclear. We aim to investigate the effect of a simultaneous combination of simple dietary advice delivered by dentists and provision of new complete dentures on dietary intake in edentulous individuals who request new dentures.

Methods/design

Through a double-blinded, parallel, randomized controlled trial in which 70 edentate persons who request new complete dentures will be enrolled, eligible study participants will be randomly allocated to either a dietary intervention group receiving dietary advice or to a control group receiving only advice on the care and maintenance of dentures. Outcome measures include daily intake of nutrients and food items, assessed using a brief self-administered diet history questionnaire; antioxidant capacity, determined using blood and urine samples; nutritional status, assessed with the Mini-Nutritional Assessment-Short Form; oral health-related quality of life, assessed with the Japanese version of the Oral Health Impact Profile-EDENT and the Geriatric Oral Health Assessment Index; subjective chewing ability; masticatory performance, assessed using a color-changeable chewing gum and a gummy jelly; patient self-assessment of dentures; mild cognitive impairment, assessed with the Japanese version of the Montreal Cognitive Assessment; and functional capacity, assessed with the Japan Science and Technology Agency Index of Competence. Outcome measures, except for antioxidant capacity, are to be implemented at three time points: at baseline and at 3 and 6 months following intervention. Antioxidant capacity data are to be collected twice: at baseline and at 3 months following intervention. Differences between the groups at 3 and 6 months and within-group changes are to be compared using the paired t test.

Discussion

Simple dietary advice that can be implemented by a dentist would be more practical in clinical practice than tailored dietary counseling. The results of this study will provide beneficial information on dietary intake changes for both edentulous individuals requesting new complete dentures and dentists.

Trial registration

University Hospital Medical Information Network Center Unique Trial Number: UMIN000017879. Registered on 12 June 2015.

Pilot Study on the Influence of Nutritional Counselling and Implant Therapy on the Nutritional Status in Dentally Compromised Patients

Objectives

To investigate the impact of implant-prosthetic rehabilitation combined with nutritional counseling on the nutritional status of patients with severely reduced dentitions.

Design

An explorative intervention study including an intra-individual comparison of 20 patients with severely reduced dentitions in terms of nutrition- and quality of life-related parameters recorded at baseline and at six and twelve months after implant-prosthetic rehabilitation.

Participants

Twenty patients from the Department of Prosthetic Dentistry of Justus-Liebig University of Giessen, with an mean age of 63 years, who had fewer than ten pairs of antagonists.

Measurements

The baseline data collection included dental status, a chewing ability test, laboratory parameters, anthropometric data (body mass index), energy supply, a 3-day dietary record, an analysis of the oral health-related quality of life (OHRQoL) with the OHIP-G14, the Mini-Mental Status (MMS) and Mini Nutritional Assessment (MNA). Six months after implantation and prosthetic rehabilitation, individual nutritional counseling was performed by a dietician. Data were again collected and analyzed. A final follow-up was conducted 12 months after prosthetic rehabilitation.

Results

Despite the highly significant improvement in masticatory ability and OHRQoL after implant-prosthetic rehabilitation, no significant changes were observed regarding MNA, anthropometric data or energy supply. Except for cholinesterase (p = 0.012), ferritin (p = 0.003), folic acid (p = 0.019) and vitamin A (p = 0.004), no laboratory parameter changed significantly during the investigation period. In addition, no general significant differences were observed for nutrient intake or food choice.

Conclusion

The present study does not confirm the assumption that the implant-prosthetic rehabilitation of patients with severely reduced residual dentitions with or without an individual nutritional counseling influences nutritional status.

Prevention of distal extension cantilever fracture in mandibular overdentures

OBJECTIVES

Fractures of distal bar extensions, supporting a mandibular overdenture, do occur with significant functional and economic consequences for the patient. This study therefore aims to evaluate the effect of different bar cross-sectional shapes and surfaces, bar extension lengths and the placement of a support rib under the distal bar extension on fracture resistance.

MATERIALS AND METHODS

The 2nd moment area and static strength were calculated for 11 frequently used bar designs using finite element analysis (FEA). For two specific designs (Ackermann round Ø 1.8mm and Dolder-Y macro, the former with and without a support rib) additional physical static and fatigue strength tests were included.

RESULTS

The FEA static strength data corresponded well to the 2nd moment area (a similar ranking when maximum allowed force was considered). The application of a rib support (Ackermann Ø 1.8mm) and limitations of the bar extension length (6mm for the Ackermann Ø 1.8mm, 8mm for the Dolder-Y macro) allowed the bars to exceed 5 × 10(6) cycles of 120 and 250N, respectively, before fracture. The region of highest stresses in FEA corresponded well with the locations of the fractures observed in static- and fatigue-testing.

CONCLUSIONS

With some simple guidelines/modifications, the number of bar extension fractures can be reduced significantly.

CLINICAL SIGNIFICANCE

This study focusses on distal bar extensions which improve the positioning of an implant supported overdenture. By combining laboratory testing and finite element simulations we aim to: (1) explain why fractures occur (dependent on physical characteristics of the bar), and (2) give clinical guidelines on how to prevent such fractures.

Small-diameter titanium Grade IV and titanium-zirconium implants in edentulous mandibles: three-year results from a double-blind, randomized controlled trial

OBJECTIVE

The aim of this study was to compare crestal bone-level changes, soft tissue parameters and implant success and survival between small-diameter implants made of titanium/zirconium (TiZr) alloy or of Grade IV titanium (Ti) in edentulous mandibles restored with removable overdentures.

MATERIALS AND METHODS

This was a randomized, controlled, double-blind, split-mouth multicenter clinical trial. Patients with edentulous mandibles received two Straumann bone-level implants (diameter 3.3 mm), one of Ti Grade IV (control) and one of TiZr (test), in the interforaminal region. Implants were loaded after 6-8 weeks and removable Locator-retained overdentures were placed within 2 weeks of loading. Modified plaque and sulcus bleeding indices, radiographic bone level, and implant survival and success were evaluated up to 36 months.

RESULTS

Of 91 treated patients, 75 completed the three-year follow-up. Three implants were lost (two control and one test implant). The survival rates were 98.7% and 97.3%, and the mean marginal bone level change was -0.78 ± 0.75 and -0.60 ± 0.71 mm for TiZr and Ti Grade IV implants. Most patients had a plaque score of 0 or 1 (54% for test and 51.7% for control), and a sulcus bleeding score of 0 (46.1% for test and 44.9% for control). No significant differences were found between the two implant types for bone-level change, soft tissue parameters, survival and success.

CONCLUSIONS

After 36 months, similar outcomes were found between Ti Grade IV and TiZr implants. The results confirm that the results seen at 12 months continue over time.

Do implant overdentures improve dietary intake? A randomized clinical trial

People wearing mandibular two-implant overdentures (IOD) chew food with less difficulty than those wearing conventional complete dentures (CD). However, there is still controversy over whether or not this results in better dietary intake. In this randomized clinical trials (RCT), the amounts of total dietary fiber (TDF), macronutrients, 9 micronutrients, and energy in diets consumed by persons with IOD and CD were compared. Male and female edentate patients ≥ 65 yrs (n = 255) were randomly divided into 2 groups and assigned to receive a maxillary CD and either a mandibular IOD or a CD. One year following prosthesis delivery, 217 participants (CD = 114, IOD = 103) reported the food and quantities they consumed to a registered dietician through a standard 24-hour dietary recall method. The mean and median values of TDF, macro- and micronutrients, and energy consumed by both groups were calculated and compared analytically. No significant between-group differences were found (ps > .05). Despite quality-of-life benefits from IODs, this adequately powered study reveals no evidence of nutritional advantages for independently living medically healthy edentate elders wearing two-implant mandibular overdentures over those wearing conventional complete dentures in their dietary intake at one year following prosthesis delivery.

Human gingival fibroblast functions are stimulated by oxidized nano-structured titanium surfaces

OBJECTIVES

The aim of this study was to analyze the features of an oxidized titanium implant surface and to evaluate its effects on the response of human gingival fibroblasts.

METHODS

10mm×10mm×1mm turned (control) and oxidized (test) titanium samples (P.H.I. s.r.l., Italy) were examined by scanning electron microscopy and atomic force microscopy and characterized by height, spatial and hybrid roughness parameters. Primary cultures of human gingival fibroblasts were seeded on titanium samples, and cell morphology, adhesion, proliferation and extracellular matrix deposition, in terms of type I collagen synthesis, were evaluated.

RESULTS

Control and test surfaces appeared considerably different at the microscopic analyses: turned samples were grooved, whereas oxidized surfaces showed a more complex micro- and nano-scaled texture, as evidenced by roughness parameters. Cell adhesion and proliferation rate, as well as collagen synthesis, were greater on oxidized vs turned surfaces.

CONCLUSIONS

Although both control and test samples were in the range of average roughness proper of smooth surfaces, they exhibited significantly different topographic properties in terms of height and, mostly, hybrid parameters. Furthermore, oxidized surfaces enhanced human gingival fibroblast adhesion, proliferation and extracellular matrix deposition, and this could be due to the different structure at micro- and nano-scale levels.

CLINICAL SIGNIFICANCE

Oxidized nanostructured titanium surfaces could have a significant clinical utilization in virtue of their affinity for soft tissue attachment at the implant neck and/or at the transmucosal portion of the prosthetic abutment.