Implants for the ageing population

Effects of bone type and occlusal loading pattern on bone remodeling in implant-supported single crown: A finite element study

PURPOSE

To assess the influence of bone types and loading patterns on the remodeling process over 12 months according to the variations in stress, strain, strain energy density (SED), and density allocation in the bone of implant-supported single crown.

MATERIALS AND METHODS

A three-dimensional finite element of a single crown implant was modeled in five different bone types (D1-D4, and grafted bone). A 200 N load was applied on an implant crown with three occlusal loading patterns (nonfunctional contact, functional contact at center, and at 2-mm offset loading). During the first 12 months after implant placement, the SED was employed as a mechanical stimulus to simulate cortical and cancellous bone remodeling.

RESULTS

Functional contact at 2-mm offset loading led to a higher bone remodeling rate and stress compared to functional contact at center and nonfunctional contact. Under 2-mm offset loading, the greatest remodeling rate after 12 months was achieved with D3 and D4, D2, grafted, and D1 cortical bone with an average peri-implant density of 1.95, 1.77, 1.56, and 1.50 g/cm3 , respectively. Meanwhile, the highest von Mises stresses were found in D4 (22.2 MPa) and D3 (21.9 MPa) bones.

CONCLUSIONS

A greater stress concentration and remodeling rate were found when an off-axial load was applied on an implant placed in low bone density. Although the fastest remodeling processes resulting in increased bone density and strength were found in D3 and D4 bone types with greater off-axial loading that may provide greater bone engagement, it could increase stress concentrations that are susceptible to inducing implant failure.

Fit and forget: The future of dental implant therapy via nanotechnology

Unlike orthopedic implants, dental implants require the orchestration of both osseointegration at the bone-implant interface and soft-tissue integration at the transmucosal region in a complex oral micro-environment with ubiquitous pathogenic bacteria. This represents a very challenging environment for early acceptance and long-term survival of dental implants, especially in compromised patient conditions, including aged, smoking and diabetic patients. Enabling advanced local therapy from the surface of titanium-based dental implants via novel nano-engineering strategies is emerging. This includes anodized nano-engineered implants eluting growth factors, antibiotics, therapeutic nanoparticles and biopolymers to achieve maximum localized therapeutic action. An important criterion is balancing bioactivity enhancement and therapy (like bactericidal efficacy) without causing cytotoxicity. Critical research gaps still need to be addressed to enable the clinical translation of these therapeutic dental implants. This review informs the latest developments, challenges and future directions in this domain to enable the successful fabrication of clinically-translatable therapeutic dental implants that would allow for long-term success, even in compromised patient conditions.

A comparative evaluation of student experience with artificial teeth used in pre-clinical fixed prosthodontics post-core undergraduate teaching programs

INTRODUCTION

Research is lacking in the use of artificial teeth for post-core techniques in undergraduate fixed prosthodontics pre-clinical education. The aim of this study was to compare the reasons for selection and explore the direct student experiences with artificial teeth used in two pre-clinical fixed prosthodontics post-core technique teaching programs conducted in consecutive years.

MATERIALS AND METHODS

Fourth year undergraduate dental students who had completed the fixed prosthodontics pre-clinical program were invited to complete an anonymous online surveys. Information was requested on the use and direct student experiences with artificial and natural teeth for post-core techniques. Quantitative data was summarised and qualitative data was clustered into topics. The reasons for selection and use of artificial and natural teeth were compared within and between the two programs.

RESULTS

36% of 70 respondents in 2020 chose to use one or more artificial teeth for the post-core exercises in the pre-clinical program compared with 94% of 77 respondents in 2021 (p < .05). The use was driven by difficulty in sourcing appropriate natural teeth. Respondents reported "ease of use" as the dominant positive user experience with the main negatives being "unrealistic simulation of natural teeth" and "different surface texture/feel when cutting."

CONCLUSION

Artificial teeth were reported to provide an appropriate and realistic simulation experience compared with extracted natural teeth and were easier to source. Students focussed on the practicalities of sourcing artificial teeth, associated costs and ease of use ahead of conceivable educational benefits. Cost limited the more widespread use of artificial teeth.

Survival Rates and Clinical Outcomes of Implant Overdentures in Old and Medically Compromised Patients

Studies on the survival rate of implant overdentures in medically compromised patients are limited because most studies exclude patients with systemic diseases affecting implant prognosis. This retrospective study aimed to evaluate the survival rate and clinical outcomes of dental implants used for overdentures in medically compromised patients. A total of 20 patients (9 men, 11 women; mean age: 67.55 ± 6.84 years, range: 53-81 years) were included. Fourteen patients had more than two systemic diseases, and nine patients had more than three systemic diseases. The mean follow-up period was 39.05 months. Of the 60 implants, 2 failed, resulting in an implant survival rate of 96.6%. No statistical differences were found in implant survival rates according to sex, age, implant diameter, restored arch, or opposing dentition (p > 0.05). A significant difference in mean marginal bone loss (MBL) was noted for restoring the arch (p = 0.022) and opposing dentition (p = 0.036). Implants placed in the mandible and with opposing removable partial dentures and complete dentures showed lower mean MBL. No significant differences in implant MBL were observed in terms of age, sex, or implant diameter (p > 0.05). Favorable clinical outcomes can be expected from implant overdentures using two or four implants in edentulous patients with systemic diseases by ensuring that the patients have a sufficient healing period and regular checkups.

Fixed prosthodontics clinical unit completions in an undergraduate curriculum: A 10-year retrospective study

INTRODUCTION

Providing undergraduate dental students with a range of clinical experiences in fixed prosthodontics procedures is an important component of dental education. The aim of this retrospective study was to analyse the types of laboratory-fabricated fixed prosthodontics clinical units completed by undergraduate students over 10 consecutive years and determine any significant trends.

MATERIALS AND METHODS

The fixed prosthodontics treatment registers from 2012 to 2021 were reviewed and the different types of completed fixed prosthodontics units and total number of fixed prosthodontics units were recorded for each year. Completed units were categorised according to the type of restoration and expressed in whole numbers and as a percentage of the total number of units completed in each year. The data were presented in table and graph form. Mann-Kendall tests were performed to statistically analyse for trends in the different restoration types.

RESULTS

Throughout all study years, porcelain bonded to metal (PBM) crowns (48.25%, range 35.70%-59.91%) were the most frequently completed fixed prosthodontics unit followed by full gold crowns (FGC) (20.84%, range 14.89%-27.30%) and all-ceramic crowns (ACC) (12.70%, range 3.67%-24.41%). Collectively, PBM, FGC and ACC comprised 81.80% of all completed fixed prosthodontics units. There were observed trends of increased use of all types of all-ceramic containing restorations, all types of all-gold containing restorations, all types of partial coverage restorations and specifically ceramic onlays and gold onlays. There were observed trends of reduced use of cast gold post-cores and all types of bridges.

CONCLUSION

PBM crowns were the mainstay laboratory-fabricated fixed prosthodontic unit completed over 10 years of undergraduate student fixed prosthodontics clinical practice.

Utilisation of Dental Services of Older People in Australia: An Economic Explanatory Model Based on Cost and Geographic Location

The increased percentage of older people retaining their natural dentition was associated with a burden of poor oral health and increased service demands. This study analyses the dental service utilisation of the ageing population in Australia and develops a modelled cost design that estimates the dental expenditure required to cover dental services for the aged population. Using the Australian Census of Population and Housing, ageing population and socioeconomic data were mapped to geographic boundaries and integrated with dental service provision data to estimate a model for the utilisation of dental services. The estimated financial cost of dental services was calculated based on the mean fees as per the Australian Dental Association's Dental Fees Survey. The utilisation of the services varied considerably across the states and also by type of service, with limited numbers using periodontic services. However, there was an increase in cost for replacement and restorative services (5020 million AUD), most evident in the socioeconomic deprivation areas. In addition, the average dental services utilisation cost increased noticeably in the lower socioeconomic deciles of all regions outside major cities. The geographic maldistribution of older people significantly affects the utilisation of dental services, especially among disadvantaged communities. A predicted cost model of 6385 million AUD would cover the oral health needs of older Australians.

Rehabilitation of extremely atrophic edentulous mandible in elderly patients with associated comorbidities: a case report and proof of concept

Background

Oral rehabilitation of the atrophic mandible is, most of the time, a challenging procedure, especially in elderly patients with associated comorbidities.

Case presentation

This clinical report describes the rehabilitation of an extremely atrophic mandible using an overdenture supported by four splinted implants, two of which are placed in the interforaminal region and the other two bypassing the inferior alveolar nerve at the level of the antegonial notch. A passive-fit bar structure splinting the four inserted implants was designed to compensate for mandibular flexure, to reduce the amount of strain on the implants, and avoid bone resorption and prosthetic failure. The 14-month postoperative cone-beam computed tomography (CBCT) and the clinical follow-up showed the bilateral integrity of the inferior alveolar nerve and the successful restoration of the atrophic edentulous mandible with a significant improvement in the patient’s quality of life.

Conclusions

The applied technique depicts several benefits such as a minimally invasive approach, reduced number of surgical interventions, reduced total treatment time, reduced treatment costs, and higher psychological acceptability.

Comparing factors affecting dental-implant loss between age groups: A retrospective cohort study

BACKGROUND

There is a growing interest in factors leading to implant failure in older people as the population aged 65 years or older continues to expand.

PURPOSE

We sought to identify differences of results in the implant survival rate and the influence of certain factors on implant failure in the older (≥65 years) and younger (<65 years) patients.

MATERIALS AND METHODS

Patients who underwent their first dental-implant surgery between July 2008 and June 2018 were included. Data on age, sex, smoking habits, medical conditions, implant location, implant size, and the presence and type of bone graft and membrane were collected and analyzed according to age group. Moreover, cumulative survival rates of implants (by Kaplan-Meier analysis) and hazard ratios (HR) of each factor (using Cox regression analysis with shared frailty) in each group were assessed and results compared between groups.

RESULTS

A total of 628 implants in 308 patients and 1904 implants in 987 patients in the older and younger groups, respectively, were assessed, with failure rates of 3.9% and 3.4%. Per Kaplan-Meier analysis, the 11-year patient-level cumulative survival rate of implant treatment was 95.3% (95% CI: 0.91-0.97) in the older and 93.9% (95% CI: 0.88-0.97) in the younger group. The HR for implant failure of the variables, except diameter of dental implants, were not statistically significant in both groups.

CONCLUSION

The outcomes of implant treatment were not considerably different between the age groups.

Dental implant care and trouble among dependent patients based on the questionnaire survey among Japanese dental practitioners

Background

Self-care and professional care of implants may prove difficult for elderly people who require nursing care. However, the actual state of care and problems remains unknown. In this study, we investigated the actual state of implant problems in elderly people living in their own home or in a nursing home who received visiting dental treatment.

Methods

We mailed questionnaire survey forms to 2339 representatives or specialists who were members of the Japanese Society of Oral Implantology, the Japanese Society of Gerodontology or the Japan Prosthodontic Society. We narrowed down the respondents to those who provided visiting dental treatment, and analyzed the actual state of implants observed during visiting dental treatment (type, care, problems, countermeasures, etc.).

Results

Of the 924 dentists who responded to the questionnaire survey, 291 (22%) provided visiting dental treatment. While the majority of implant types encountered in the previous 12 months were root-form implants, there were still a certain number of blade and subperiosteal implants. Daily implant care involved mostly cleaning with a toothbrush + auxiliary tools. The most frequent implant problems encountered in the past were difficulty in cleaning and peri-implantitis. Medication and antiphlogistic treatment were most frequently adopted as countermeasures to implant problems, followed by observation. When we classified the results into those for the dentists who provided implant treatment and those for the dentists who did not, we found that many of the dentists who did not provide implant treatment opted for observation or medication, while those who provided implant treatment also implemented removal of superstructure, retightening of screws, repair and so forth.

Conclusions

We found that many of the implant troubles encountered by dentists who provided visiting dental care were difficulty in cleaning or peri-implantitis, and that the actions taken against these troubles varied depending on the experience of the dentist performing the implant treatment. Our study also revealed that dentists who provide visiting dental care need to acquire knowledge and skills of implant treatment, to have actions prepared in case they encounter such cases, or to closely coordinate with dentists who specialize in implants.

"ABCD" Implant Classification: A Comprehensive Philosophy for Treatment Planning in Completely Edentulous Arches

A thorough and precise treatment plan that considers various factors such as age, availability of bone, interarch space for prosthesis design, smile line, lip support, patient desires, and economics is a necessity before implant surgery. Many previous classification systems for treatment planning in edentulous situations tend to focus on only a certain parameter such as esthetics, or available bone volume, or are specifically designed for the maxilla or mandible. The authors have proposed a simplified and universal ABCD classification that uses the 4 vital parameters of age, bone volume, cosmetic display, and degree of resorption to create an algorithm that satisfies the treatment needs of every patient. Various permutations of the 4 parameters can be used to arrive at a solution that streamlines the further phases of the rehabilitative process. The aim of the present article is to provide a science-driven approach to understand a patient's individual needs with careful attention to the interplay of all the aforementioned factors in the decision-making process.

Oral health behaviours of older Australian men: the Concord Health and Ageing in Men Project

BACKGROUND

The Concord Health and Ageing in Men Project (CHAMP) is a cohort study of the health of a representative sample of older Australian men. The aim of this paper is to describe the oral health behaviours and dental service use of CHAMP participants and explore associations between oral health behaviours with and general health status.

METHOD

Information collected related to socio-demographics, general health, oral health service-use and oral health behaviours. Key general health conditions were ascertained from the health questionnaire and included physical capacity and cognitive status.

RESULTS

Fifty-seven percent of the men reported visiting a dental provider at least once or more a year and 56.7% did so for a "dental check-up". Of those with some natural teeth, 59.3% claimed to brush their teeth at least twice or more a day. Most men (96%) used a standard fluoride toothpaste. Few participants used dental floss, tooth picks or mouth-rinses to supplement oral hygiene. Cognitive status and self-rated general health were associated with dental visiting patterns and toothbrushing behaviour.

CONCLUSIONS

Most older men in CHAMP perform favourable oral health behaviours. Smoking behaviour is associated with less favourable dental visiting patterns, and cognitive status with toothbrushing behaviour.

Accuracy of mucosa supported guided dental implant surgery

Implant deviation at platform and apex was comparable to that seen in similar studies, showing that Mucosa Supported Guided Dental Implant Surgery can be a safe implant placement technique. Implant diameter and length, bone density and density deviations showed moderate strong correlation with apical deviation.

A preliminary report on dental implant condition among dependent elderly based on the survey among Japanese dental practitioners

Background

The objective of this study was to ascertain the situation relevant to implants, the status of oral self-care, the status of aftercare provided by the dentist who placed the implant, and the usage status of the implant card, in homebound or institutionalized older adults who are receiving home-visit dental care due to the inability to visit a dental clinic on their own.

Methods

A survey questionnaire was sent by post mail to 2339 people who are representative members or dental specialists belonging to any of the following three academic societies: Japanese Society of Oral Implantology, Japanese Society of Gerodontology, and Japan Prosthodontic Society. The survey questions asked were about provision/no provision of implant treatment, provision/no provision of home-visit dental care, the situation of patients after implant treatment, the situation of implants in the context of home-visit dental care, and the usage status and recognition of the implant card.

Results

No less than 30% of the dentists had patients who were admitted to the hospital or became homebound after receiving implant treatment at their clinic. Twenty-two percent of the dentists had been consulted about the implants. Dentists who continued to provide post-operative implant care through home-visit dental care accounted for approximately 80%. On the other hand, however, 40% of the dentists did not know the post-implantation status of their implant patients. Of the patients receiving home-visit dental care, approximately 3% had implants (identified mainly by visual inspection). It was found that more than 50% of the dentists offering implant treatment did not use the implant card, and even in cases where it was used, most of the cards were not in the standardized format.

Conclusions

Within the limitation of low response rate to the questionnaire in this preliminary study, we concluded that many of practitioners including specialists indicated the need of universal record of implant for dependent elderly cares.

Twenty-year analysis of implant treatment in an Australian public dental clinic

BACKGROUND

This retrospective cohort study reviewed dental implant treatment completed at the Adelaide Dental Hospital over a 20-year period.

METHODS

The database of implant treatment completed between 1996 and 2015 was analysed for patient, implant, prosthesis and operator specifics together with known implant status.

RESULTS

Three hundred and twenty patients (mean age, 51.50 years) were treated with 527 implants. One hundred and eighty-four female patients received 296 implants and 136 males received 231 implants. Three hundred implants were restored with single crowns, 147 implants were restored with 63 mandibular implant overdentures, five implants were restored with two maxillary implant overdentures and 67 implants were restored with 20 full-arch fixed prostheses. The overall known implant survival rate was 87.67%. Mandibular implant overdentures had a risk of implant failure four times that of single implant-retained crowns that was statistically significant (P = 0.0100).

CONCLUSIONS

Implant treatment completed in this public sector clinic using finite resources and a defined system of patient and restorative selection criteria demonstrated a high known implant survival rate. Utilizing a structured and maintained patient recall protocol, it would be ideal to investigate further parameters of interest, particularly those that could improve treatment delivery and longevity.

Oral health of community-dwelling older Australian men: the Concord Health and Ageing in Men Project (CHAMP)

BACKGROUND

The Concord Health and Ageing in Men Project (CHAMP) is a cohort study of the health of a representative sample of Australian men aged 70 years and older. The aim of this report is to describe the oral health of these men.

METHODS

Oral health was assessed when the men were all aged 78 years or older. Two calibrated examiners conducted a standardized intraoral assessment. Descriptive data were analysed by statistical association tests. Participants were excluded from the collection of some periodontal assessments if they had a medical contraindication.

RESULTS

Dental assessments of 614 participants revealed 90 (14.6%) were edentate. Men had a mean of 13.8 missing teeth and 10.3 filled teeth. Dentate participants had a mean of 1.1 teeth with active coronal decay. Those in the low-income group had a higher rate of decayed teeth and lower rate of filled teeth. Thirty-four participants (5.5%) had one or more dental implants, and 66.3% relied on substitute natural teeth for functional occlusion. Of those with full periodontal assessments; 90.9% had sites with pocket depths of 3 mm or more, 96.6% had sites with CAL of 5 mm or more, and 79.7% had three or more sites with GI scores of 2 or more.

CONCLUSIONS

There was a high prevalence of periodontal diseases and restorative burden of dentitions, which suggests that greater attention needs to be given to prevention and health maintenance in older Australian men.

Dental implant loss in older versus younger patients: a systematic review and meta-analysis of prospective studies

The aim of this systematic review was to evaluate implant loss in younger and older patients. An electronic search of four databases (MEDLINE, EMBASE, SCOPUS and the Cochrane Library) was undertaken until May 2016 without time restriction and was supplemented by manual searching. Prospective cohorts were included if they met the following criteria: (i) presence of an exposed group (older subjects) with a minimum age of 60 years; (ii) presence of a control group (younger subjects) with a maximum age of 59 years; and (iii) outcome data considering implant survival or loss. Meta-analyses were performed to evaluate the impact of ageing on implant failure. Of 4152 potentially eligible articles, four were included in the qualitative analysis and quantitative synthesis. The pooled estimates suggest that the risk of implant loss in older patients is not significantly higher (RR = 0·92; 95% CI 0·43-1·96, P = 0·83) when compared to younger subjects. This systematic review suggests that age is not a limiting factor for dental implant therapy.