Outcomes of dental implants placed in a surgical training programme

The influence of antineoplastic agents on the peri-implant bone around osseointegrated titanium implants: an in vivo histomorphometric and immunohistochemical study

BACKGROUND AND OBJECTIVE

The interaction between antineoplastic drugs used for treating cancer and non-affected tissues remains poorly assessed and may be critical for maintaining the quality of life for patients during and after treatment. This pre-clinical study evaluated the effects of cisplatin (CIS) and 5-fluorouracil (5-FU) on the peri-implant repair process around osseointegrated titanium implants installed in the tibiae of rats.

MATERIAL AND METHODS

Were used 90 male rats, randomly divided into three groups (n = 30): physiological saline solution (PSS), CIS, and 5-FU. Titanium implants (4.0 × 2.2 mm) were inserted in both tibiae of all animals at day 0. The animals received either PSS, CIS, or 5-FU at 35 and 37 days. Euthanasia was performed at 50, 65, and 95 days after surgery. Histometric (bone/implant contact [BIC]) and bone area fraction occupancy (% BAFO), histological, and immunohistochemical (for bone morphogenetic protein 2/4 [BMP2/4], Runt-related transcription factor 2 [RUNX2], osteocalcin [OCN], and tartrate-resistant acid phosphatase [TRAP]) analyses were performed. Data were statistically analyzed.

RESULTS

Groups CIS and 5-FU presented lower BIC and lower BAFO as compared with PSS in all time points. The imbalance in bone turnover was observed by the lower number of BMP2/4-, RUNX2-, and OCN-positive cells/mm2 and the higher number of TRAP-positive cells/mm in groups CIS and 5-FU as compared with PSS in all time points. Persistent and exacerbated inflammation was observed in groups CIS and 5-FU.

CONCLUSIONS

Both antineoplastic agents interfered negatively in the bone turnover around osseointegrated titanium implants.

CLINICAL RELEVANCE

Closer and more careful follow-up of patients with osseointegrated implants that will undergo chemotherapy with either CIS or 5-FU shall be performed.

The effectiveness of immediate implant placement for single tooth replacement compared to delayed implant placement: A systematic review and meta-analysis

AIM

To compare immediate implant placement (IIP) to delayed single implant placement (DIP, ≥3 months post-extraction) in terms of implant survival (primary outcome), surgical, clinical, aesthetic, radiographic and patient-reported outcomes (secondary outcomes).

MATERIALS AND METHODS

Two reviewers independently performed an electronic search in PubMed, Web of Science, EMBASE and Cochrane and a hand search to identify eligible studies up to May 2018. Only randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs) comparing IIP to DIP with at least 1 year of follow-up were selected for a qualitative analysis and meta-analysis.

RESULTS

The search identified 3 RCTs and 5 NRSs out of 2,589 titles providing data on 473 single implants (IIP: 233, DIP: 240) that had been in function between 12 and 96 months. One RCT showed unclear risk of bias, whereas all other studies demonstrated high risk. Meta-analysis showed significantly lower implant survival for IIP (94.9%) as compared to DIP (98.9%) (RR 0.96, 95% CI [0.93; 0.99], p = 0.02). All were early implant failures. A subgroup meta-analysis demonstrated a trend towards lower implant survival for IIP when postoperative antibiotics had not been administered (RR: 0.93, 95% CI [0.86; 1.00], p = 0.07). This was not observed among studies including the administration of postoperative antibiotics (RR: 0.98, 95% CI [0.94; 1.02], p = 0.35). Meta-analyses showed similar probing depth (WMD 0.43 mm, 95% CI [-0.47; 1.33], p = 0.35) and aesthetic outcomes as assessed by the pink aesthetic score (standardized WMD -0.03, 95% CI [-0.46; 0.39], p = 0.88) for IIP and DIP. Data on marginal bone loss were conflicting and highly biased. Soft tissue recession was underreported and available data were highly biased. Patient-reported outcomes were underreported, yet both IIP and DIP seemed well tolerated.

CONCLUSION

Immediate implant placement demonstrated higher risk for early implant loss than DIP. There is a need for RCTs comparing IIP to DIP with CBCT analyses at different time points and data on midfacial recession with the preoperative status as baseline. In these studies, the need for hard and soft tissue grafting should also be evaluated.

The influence of Cisplatin-based chemotherapy on the osseointegration of dental implants: An in vivo mechanical and histometrical study

OBJECTIVES

To evaluate the effect of Cisplatin on bone repair and mineralization around implants and on the mechanical properties of bone tissue.

MATERIALS AND METHODS

Forty-three Wistar rats were randomly divided into two groups: Cisplatin (CIS, medication) and control (CTL, placebo solution), administered once a week for 4 weeks. After 4 weeks, implants were installed in both tibiae metaphysis. After 30 and 60 days, the animals were sacrificed and their femurs and tibiae were removed. Femurs were subjected to mechanical tests and tibiae for removal torque, arrangement and distribution of collagen fibers, morphometrical analyses (bone tissue in contact with the implant surface [BIC] and areal fraction between implant threads occupied by bone tissue [BAFO]) and scanning electron microscopy to calcium and calcium/phosphorus analysis. Data were analyzed by ANOVA or MANOVA, and Tukey or Games-Howell post hoc tests, respectively (α = 0.05).

RESULTS

The CTL specimens had significantly higher values (0.0001 ≤ p≤0.036) of strength (N), removal torque (N/cm² ), %BIC, and %BAFO than CIS specimens, being their best results at day 60. No significant differences were found among the groups regarding the values of deformation, percentage of calcium, and calcium/phosphorus ratio. In CIS groups, there was a reduction in the organization of collagen at the bone/implant interface, resulting in a trabecular bone with thin trabeculae and birefringent collagen and irregular arrangement.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Cisplatin interfered negatively in the repair and mineralization around dental implants, as well as on the quality of the bone tissue, mainly in the period of 30 days after the implant placement.

Complications of augmentation procedures for dental implants in private practice, Victoria, Australia

PURPOSE

This study audited complications associated with augmentation for dental implants, retrospectively over a 5-year period in a variety of private dental practices in Victoria (Australia).

METHODS

Complications were categorized as surgical or biological and compared to a group not requiring augmentation. Implant factors underwent univariate and multivariate analysis.

RESULTS

The study assessed 8486 implants with 26.9% undergoing augmentation. Augmentation had no effect on implant survival, however, a significant increase in complications for those implants requiring augmentation was found (P = <0.001). The hard tissue augmented group had significantly more cases of insufficient bone/dehiscences at implant placement (P < 0.001), and post-placement bone loss (P = 0.0014). These implants were grafted simultaneously (P < 0.05) with particulate autogenous bone and/or Bio-Oss (P < 0.05) with resorbable xenograft membrane (P < 0.001). There was significantly more bone loss in open sinus lifted cases than implants placed in native bone (1.90% v 0.30%; P = 0.009).

CONCLUSIONS

The study demonstrated no increase in graft complications that could be related to any specific augmentation technique, suggesting that routine grafting procedures used in private practice were safe and appropriate. Previously augmented sites were found to be more likely to require further augmentation at implant placement.

Peri-implant inflammation and marginal bone level changes around dental implants in relation to proximity with and bone level of adjacent teeth

OBJECTIVES

This retrospective study assessed radiographic bone changes and prevalence of inflammation around teeth and neighbouring implants supporting a single-unit fixed dental prosthesis (FDP), in relation to implant- positioning and characteristics.

MATERIAL AND METHODS

Patients with an implant-supported FDP in function for at least 1 year were recruited. The radiographic horizontal and vertical position of the implants were identified. Probing depth (PD), bleeding on probing (BOP) and radiographic bone level around implants and adjacent teeth at the time of placement, prosthesis delivery, and the most recent review were assessed.

RESULTS

98 patients with 195 implants were evaluated for a mean of 37.8 months. Survival rate was 99.6% and success ranged from 31.3% to 91.3% when different success criteria were utilized. Significantly greater interproximal bone loss around teeth and higher prevalence of interproximal peri-implant inflammation occurred when the horizontal distance of BL implants was <1 mm, but not with TL implants. There was no significant impact of the corono-apical positioning of the implants on marginal bone loss.

CONCLUSION

Proximity of implants to adjacent teeth of <1 mm leads to increased prevalence of inflammation and interproximal bone resorption at the teeth adjacent to bone level implants.

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.

Bone augmentation as an adjunct to dental implant rehabilitation in patients with diabetes mellitus: A review of literature

The aim of the present article is to review the success of bone augmentation performed as an adjunct to dental implant rehabilitation in patients with diabetes mellitus. A literature review was conducted in PubMed on this topic, which yielded a total of 102 publications. For inclusion, publications had to be human studies, written in English language and should report on the success of bone augmentation as an adjunct to dental implant rehabilitation in diabetic patients. After screening the titles and abstracts, 11 full texts publications were obtained, of which seven were included in the review. These studies provided data on various bone augmentation techniques such as sinus floor elevation (SFE), guided bone regeneration (GBR), and onlay bone grafting. Even though the current review revealed that there are not many studies reporting data relevant to the analyzed topic, the data obtained suggests that; (1) staged GBR technique should be considered more feasible and predictable for bone augmentation, (2) clinicians must take meticulous care when planning and conducting SFE, and (3) block bone augmentation technique should be avoided.

Survival rates and complication types for single implants provided at the Melbourne Dental School

BACKGROUND

Single implants and implant-supported single crowns (ISSCs) have become popular treatment modalities for single tooth replacement. Studies have identified high implant survival rates, but also many complications. The aim of this five-year retrospective study was to assess the survival rates, complication types and occurrences for single implants and ISSCs at the Melbourne Dental School (MDS) in Victoria, Australia.

METHODS

A search of the Royal Dental Hospital of Melbourne (RDHM) database was conducted for data on all implant treatment and reported complications during the period between 1 January 2005 and 31 December 2009. Complications were categorized into surgical, biological and restorative types.

RESULTS

A total of 622 implant fixtures and 444 ISSCs were inserted into 406 patients. Seventeen implants failed during the mean follow-up time of 2.18 years, yielding a 2.7% failure rate and an estimated one- and five-year survival rate of 98.8% and 93.9%, respectively. The cumulative surgical, biological and restorative complication incidences were 11.9%, 17.6% and 14.1%, respectively.

CONCLUSIONS

This study confirmed that single tooth replacement using implant therapy within a teaching environment had a high survival rate. However, complications frequently occurred. This article only provides a descriptive analysis. Correlation analysis between variables would provide greater insight into the causes of complications.

Implant dentistry in postgraduate university education. Present conditions, potential, limitations and future trends

INTRODUCTION

In recent years, opportunities for postgraduate university education in implant dentistry have increased significantly, with an increase in both the number but also the complexity of available postgraduate programmes. However, there appears to be a lack of standards directing the learning outcomes of such programmes.

METHODS

A scientific literature search was conducted for publications reporting on university programmes within implant dentistry, including description of programmes and evaluation of learning outcomes. A separate Internet search was conducted to collect information on existing university programmes as presented on university websites.

RESULTS

Implant dentistry has reached a critical mass of an independent, multidisciplinary and vibrant domain of science, which combines knowledge and discovery from many clinical and basic sciences. Many university programmes conclude with a master's or equivalent degree, but there appears to be a great diversity with regard to duration and learning objectives, as well as targeted skills and competences. The importance of implant dentistry has also increased within established specialist training programmes. There was little indication, however, that the comprehensive aspects of implant dentistry are present in all specialist training programmes where implants are being covered.

CONCLUSIONS

Although universities should maintain the options of designing academic programmes as they best see fit, it is imperative for them to introduce some form of transparent and comparable criteria, which will allow the profession and the public to relate the degree and academic credentials to the actual skills and competences of the degree holder. With regard to established specialist training programmes, the interdisciplinary and comprehensive nature of implant dentistry needs to be emphasised, covering both surgical and restorative aspects. Finally, implant dentistry is not, at present, a dental specialty. The profession has not reached a consensus as to whether the introduction of a new recognised specialist field is either necessary or desired.

Assessment of the autogenous bone graft for sinus elevation

OBJECTIVES

The posterior maxillary region often provides a limited bone volume for dental implants. Maxillary sinus elevation via inserting a bone graft through a window opened in the lateral sinus wall has become the most common surgical procedure for increasing the alveolar bone height in place of dental implants in the posterior maxillary region. The purpose of this article is to assess the change of bone volume and the clinical effects of dental implant placement in sites with maxillary sinus floor elevation and autogenous bone graft through the lateral window approach.

MATERIALS AND METHODS

In this article, the analysis data were collected from 64 dental implants that were placed in 24 patients with 29 lacks of the bone volume posterior maxillary region from June 2004 to April 2011, at the Department of Oral and Maxillofacial Surgery, Inha University Hospital. Panoramic views were taken before the surgery, after the surgery, 6 months after the surgery, and at the time of the final follow-up. The influence of the factors on the grafted bone material resorption rate was evaluated according to the patient characteristics (age and gender), graft material, implant installation stage, implant size, implant placement region, local infection, surgical complication, and residual alveolar bone height.

RESULTS

The bone graft resorption rate of male patients at the final follow-up was significantly higher than the rate of female patients. The single autogenous bone-grafted site was significantly more resorbed than the autogenous bone combined with the Bio-Oss grafted site. The implant installation stage and residual alveolar height showed a significant correlation with the resorption rate of maxillary sinus bone graft material. The success rate and survival rate of the implant were 92.2% and 100%, respectively.

CONCLUSION

Maxillary sinus elevation procedure with autogenous bone graft or autogenous bone in combination with Bio-Oss is a predictable treatment method for implant rehabilitation.

Systematic review of the survival rate and the incidence of biological, technical, and aesthetic complications of single crowns on implants reported in longitudinal studies with a mean follow-up of 5 years

OBJECTIVE

To assess the 5-year survival of implant-supported single crowns (SCs) and to describe the incidence of biological, technical, and aesthetic complications. The focused question was: What is the survival rate of implants supporting single crowns and implant-supported crowns with a mean follow-up of 5 years and to which extent do biological, technical, and aesthetic complications occur?

METHODS

A Medline search (2006-2011) was performed for clinical studies focusing on implant-supported SCs with a mean follow-up of at least 5 years. The search was complemented by an additional hand search and the inclusion of 24 studies from a previous systematic review (Jung et al. 2008a). Survival and complication rates were analyzed using random-effects Poisson's regression models to obtain summary estimates of 5- and 10-year proportions.

RESULTS

Forty-six studies derived from an initial search count of 1083 titles and the complementary publications from the previous systematic review (Jung et al. 2008a) were selected and the data were extracted. Based on the meta-analysis, survival of implants supporting SCs at 5 years amounted to 97.2% (95% CI: 96.3-97.9%), and at 10 years amounted to 95.2% (95% CI: 91.8-97.2%). The survival of implant-supported SCs was 96.3% (95% CI: 94.2-97.6%) after 5 years and 89.4% (95% CI: 82.8-93.6%) after 10 years. For biological complications, a 5-year cumulative soft tissue complication rate of 7.1% (95% CI: 4.4-11.3%) and a cumulative complication rate for implants with bone loss >2 mm of 5.2% (95% CI: 3.1-8.6%) were calculated. Technical complications reached a cumulative incidence of 8.8% (95% CI: 5.1-15.0%) for screw-loosening, 4.1% (95% CI: 2.2-7.5%) for loss of retention, and 3.5% (95% CI: 2.4-5.2%) for fracture of the veneering material after 5 years. The cumulative 5-year aesthetic complication rate amounted to 7.1% (95% CI: 3.6-13.6%).

CONCLUSIONS

The outcomes of the meta-analysis demonstrated high implant survival rates for both the single tooth implants and the respective single crowns after 5 and 10 years. However, technical, biological, and aesthetic complications were frequent.