A systematic review of implant outcomes in treated periodontitis patients

Clinical outcomes and risk factor analysis of dental implants inserted with lateral maxillary sinus floor augmentation: A 3- to 8-year retrospective study

AIM

To evaluate the 3- to 8-year outcomes of dental implants placed with lateral sinus floor augmentation (LSFA) and to identify factors affecting implant survival.

MATERIALS AND METHODS

This retrospective study was performed by screening all implants placed with LSFA procedures, which were conducted between January 2012 and December 2016. Subantral bone gain (SABG) and apical bone height (ABH) were assessed using panoramic radiographs. The cumulative survival rate of implants was analysed using life-table analysis and Kaplan-Meier survival curves. The influential risk factors affecting survival were assessed using univariate log-rank tests and multivariable mixture cure rate model. Implant complications were recorded.

RESULTS

Based on the established criteria, a total of 449 patients (760 implants) were included in this study. In the 3- to 8-year follow-up (mean ± SD, 5.81 ± 1.33 years), 15 implants in 14 patients failed, with a CRS of 96.81% on an implant basis and 95.07% on a patient basis. A history of periodontitis and poor compliance with supportive periodontal treatment was associated with a significantly higher risk of implant failure at both implant and patient levels. Significant decreases in ABH occurred during each yearly interval except for 3 years. A similar trend has been observed for SABG at 1, 2, 6 and 8 years. The total complication rate was 31.84% on implant basis, with peri-implant mucositis (21.58%) being the most frequent biologic complication and porcelain cracking (5.00%) being the most common technical complication.

CONCLUSIONS

Implant with LSFA is a reliable treatment option in atrophic maxilla. A history of periodontitis without regular supportive periodontal treatment was identified as a predictor for implant failure. Slight but significant shrinkage of vertically augmented bone can be observed after implant placement.

Maintenance of peri-implant health in general dental practice

The long-term maintenance or restoration of peri-implant tissues' health depends on the strategic implementation of preventive measures and interventions. These measures should be initiated before implant placement and continued throughout a patient's lifetime, as part of a tailored and comprehensive supportive peri-implant care (SPIC) programme. Central to the clinical efforts of maintaining and rehabilitating peri-implant tissues are several key factors, including the ongoing assessment and frequent monitoring of tissue health and stability, proactive oral health promotion, the control of risk factors and indicators and the provision of professional plaque biofilm removal. It is of paramount importance to underline that SPIC should not limit its scope exclusively to patients already in a state of peri-implant health; in fact, it is imperative that it should extend its protective effect to individuals who have been previously diagnosed and treated for peri-implant diseases, focusing on preventing its recurrence and progression, thereby avoiding further complications, such as implant loss.This narrative review presents an overview of the current literature on the maintenance of peri-implant tissues' health and the steps of SPIC providing insights into the critical factors to be considered when managing dental implant patients in the general dental practice.

Bone regeneration in implant dentistry: Which are the factors affecting the clinical outcome?

The key factors that are needed for bone regeneration to take place include cells (osteoprogenitor and immune-inflammatory cells), a scaffold (blood clot) that facilitates the deposition of the bone matrix, signaling molecules, blood supply, and mechanical stability. However, even when these principles are met, the overall amount of regenerated bone, its stability over time and the incidence of complications may significantly vary. This manuscript provides a critical review on the main local and systemic factors that may have an impact on bone regeneration, trying to focus, whenever possible, on bone regeneration simultaneous to implant placement to treat bone dehiscence/fenestration defects or for bone contouring. In the future, it is likely that bone tissue engineering will change our approach to bone regeneration in implant dentistry by replacing the current biomaterials with osteoinductive scaffolds combined with cells and mechanical/soluble factors and by employing immunomodulatory materials that can both modulate the immune response and control other bone regeneration processes such as osteogenesis, osteoclastogenesis, or inflammation. However, there are currently important knowledge gaps on the biology of osseous formation and on the factors that can influence it that require further investigation. It is recommended that future studies should combine traditional clinical and radiographic assessments with non-invasive imaging and with patient-reported outcome measures. We also envisage that the integration of multi-omics approaches will help uncover the mechanisms responsible for the variability in regenerative outcomes observed in clinical practice.

Peri-implantitis as the consequence of errors in implant therapy

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. It is a highly prevalent disease, as extensively estimated by large-population, cross-sectional studies. As peri-implant diseases represent opportunistic infections, it is reasonable to assume that nonideal conditions, local and/or general, may favor the progression of peri-implant inflammation. Some of these conditions could be a result of poor planning and/or inadequate execution of any step of the entire process treatment. This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term.

Laser-Modified Ti Surface Improves Paracrine Osteogenesis by Modulating the Expression of DKK1 in Osteoblasts

Titanium surface modifications are widely used to modulate cellular behavior by recognition of topographical cues. However, how those modifications affect the expression of mediators that will influence neighboring cells is still elusive. This study aimed to evaluate the effects of conditioned media from osteoblasts cultured on laser-modified titanium surfaces on the differentiation of bone marrow cells in a paracrine manner and to analyze the expression of Wnt pathway inhibitors. Mice calvarial osteoblasts were seeded on polished (P) and Yb:YAG laser-irradiated (L) Ti surfaces. Osteoblast culture media were collected and filtered on alternate days to stimulate mice BMCs. Resazurin assay was performed every other day for 20 days to check BMC viability and proliferation. After 7 and 14 days of BMCs maintained with osteoblasts P and L-conditioned media, alkaline phosphatase activity, Alizarin Red staining, and RT-qPCR were performed. ELISA of conditioned media was conducted to investigate the expression of Wnt inhibitors Dickkopf-1 (DKK1) and Sclerostin (SOST). BMCs showed increased mineralized nodule formation and alkaline phosphatase activity. The L-conditioned media enhanced the BMC mRNA expression of bone-related markers Bglap, Alpl, and Sp7. L-conditioned media decreased the expression of DKK1 compared with P-conditioned media. The contact of osteoblasts with Yb:YAG laser-modified Ti surfaces induces the regulation of the expression of mediators that affect the osteoblastic differentiation of neighboring cells. DKK1 is among these regulated mediators.

Fatigue Resistance of Dissected Lower First Molars Restored with Direct Fiber-Reinforced Bridges—An In Vitro Pilot Study

The aim of this research was to evaluate the mechanical impact of utilizing different fiber-reinforced composite (FRC) systems to reinforce inlay-retained bridges in dissected lower molars with different levels of periodontal support. A total of 24 lower first molars and 24 lower second premolars were included in this study. The distal canal of all molars received endodontic treatment. After root canal treatment, the teeth were dissected, and only the distal halves were kept. Standardized class II occluso-distal (OD) (premolars) and mesio-occlusal (MO) (dissected molars) cavities were prepared in all teeth, and premolar–molar units were created. The units were randomly distributed among four groups (n = six/group). With the aid of a transparent silicone index, direct inlay-retained composite bridges were fabricated. In Groups 1 and 2, both discontinuous (everX Flow) and continuous (everStick C&B) fibers were used for reinforcement, while in Groups 3 and 4, only discontinuous fibers (everX Flow) were used. The restored units were embedded in methacrylate resin, simulating either physiological periodontal conditions or furcation involvement. Subsequently, all units underwent fatigue survival testing in a cyclic loading machine until fracture, or a total of 40,000 cycles. Kaplan–Meyer survival analyses were conducted, followed by pairwise log-rank post hoc comparisons. Fracture patterns were evaluated visually and with scanning electron microscopy. In terms of survival, Group 2 performed significantly better than Groups 3 and 4 (p < 0.05), while there was no significant difference between the other groups. In the case of impaired periodontal support, a combination of both continuous and discontinuous short FRC systems increased the fatigue resistance of direct inlay-retained composite bridges compared to bridges that only contained short fibers. Such a difference was not found in the case of sound periodontal support between the two different bridges.

Risk indicators of long-term outcome of implant therapy in patients with a history of severe periodontitis or no history of periodontitis: A retrospective cohort study

OBJECTIVE

The aim of this retrospective cohort study was to assess factors associated with peri-implant disease in partially edentulous patients with a history of severe periodontitis or no history of periodontitis.

METHODS

Partially edentulous patients with a history of severe periodontitis/without history of periodontitis who received implant surgery within the past 6 to 8 years were recalled. Clinical and radiographic examinations were recorded. Periodontal probing depth, marginal bone loss (MBL) and peri-implantitis were considered as the primary outcome and peri-implant bleeding on probing (BOP) was considered as the secondary outcome. The following criteria were considered as the predictors, as well: history of severe periodontitis, gender, age, smoking, brushing frequency, recall interval, full-mouth plaque score, full-mouth bleeding score, splinted prosthesis, open/tight interproximal contact, width of keratinized mucosa, mucosal thickness, implants placed in the grafted bone and implant type. Univariate and multivariate regression analyses were utilized.

RESULTS

A total of 88 patients (186 implants) fulfilled the study. Forty-seven patients (108 implants) had a history of severe periodontitis and 41 patients (78 implants) had no history of periodontitis. There was a higher chance of peri-implantitis in patients with a history of severe periodontitis (OR = 11.13; p = 0.045), implants with lack of peri-implant KM (<2 mm) and implants placed in the grafted bone (OR = 14.94, p < 0.001; OR = 4.93, p = 0.047). The risk of peri-implant MBL ≥3 mm was higher in patients with greater FMBS (OR = 1.20; p < 0.001). The chance of peri-implant BOP was independently higher in patients who brushed their teeth at most once per day (OR = 3.20; p = 0.04), higher FMBS (OR = 1.16; p < 0.001) and irregular recall visits (OR = 15.34; p = 0.001).

CONCLUSIONS

Partially edentulous patients with the history of severe periodontitis, lack of peri-implant KM and implants placed in bone-grafted sites expressed higher probability of peri-implantitis. In addition, inadequate frequency of brushing (at most once daily) and irregular recall visits were associated with greater chance of peri-implant BOP.

A Randomized Clinical Trial Comparing Implants Placed in Two Different Biomaterials Used for Maxillary Sinus Augmentation

The objective of this study was to compare marginal bone loss, surgical and clinical complications, and dental implant survival rate in bilateral maxillary sinus augmented by autologous or porcine xenograft. A randomized controlled clinical trial using split-mouth design enrolled 12 consent adult patients (59.7 ± 8.7 years), who received bilateral maxillary sinus floor augmentation for oral rehabilitation with implant-supported prosthesis. Each patient received both the autologous bone from the mandible (control) or porcine xenograft (test) during the random bilateral sinus lift surgery. A total of 39 dental implants were placed in the posterior maxilla of the 12 patients after 6 months, being rehabilitated after the respective osseointegration period. Both graft materials demonstrated a high implant survival rate at 12 months: 95% for the xenograft side, only 1 implant without osseointegration, and 100% for the autologous side. Radiographic bone loss was low and similar for both groups: control group with a mean of 0.063 ± 0.126, and test group with a mean of 0.092 ± 0.163. No major surgical-related complications have occurred. Only one patient had several prosthetic complications due to fractures of prosthetic components. The maxillary sinus augmentation procedure, both with autologous bone and porcine xenograft materials, is an excellent clinical option procedure for the prosthetic rehabilitation of atrophic maxillae, with low marginal bone loss after one year follow-up, few clinical complications, and a high implant survival rate.

The efficacy of bone reconstructive therapies in the management of peri-implantitis. A systematic review and meta-analysis

AIM

To evaluate the efficacy of bone reconstructive procedures for the reduction of probing pocket depth (PPD), bleeding on probing (BOP), and suppuration in peri-implantitis-related bone defects at ≥12-month follow-up.

MATERIALS AND METHODS

Three databases were searched for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) that compared bone reconstructive therapies to access flap surgery (AFS) (Focused Question-FQ 1), and RCTs, CCTs, and prospective case series that assessed the efficacy of reconstructive therapies (FQ 2). Meta-analysis was performed for FQ1 when more than three studies were identified, while for FQ2 a network was drawn based on RCTs with common treatment arms.

RESULTS

Seven RCTs were identified for FQ1 while five RCTs and six prospective case series for FQ2. There was no significant difference in PPD change between AFS and reconstructive surgery (-0.387; p = .325) at 12 months. Furthermore, no clear differences in terms of PPD and BOP changes resulted from the different reconstructive therapies included in the network. Only a small percentage of treated cases with any modality achieved peri-implantitis resolution, as defined by different composite outcomes.

CONCLUSIONS

Reconstructive surgery does not offer significant improvements in peri-implant clinical parameters as compared to AFS at 12 months. It was not possible to establish a hierarchy of efficacy among the different biomaterials employed for reconstructive surgery.

Immediate loaded fixed complete dentures supported by implants in patients with a history of periodontitis: A retrospective cohort study of 2 to 7 years

STATEMENT OF PROBLEM

The outcome of implant-supported fixed complete dentures in edentulous patients with a history of periodontitis is unclear.

PURPOSE

The purpose of this retrospective clinical study was to assess the clinical outcomes of immediate loaded fixed complete dentures in individuals with a history of periodontitis and to analyze risk factors related to implant failure.

MATERIAL AND METHODS

A total of 642 implants (146 prostheses) in 119 patients were included. The follow-up period ranged from 2 to 7 years. Implant survival rates, marginal bone loss, mechanical complications, biologic complications, and patient satisfaction were evaluated. The Pearson chi-square test, independent samples t test, and multivariate generalized estimating equation were performed for statistical analysis (α=.05).

RESULTS

Eleven implants in 9 patients failed, leading to overall survival rates of 98.3% at the implant level and 92.4% at the patient level. The mean ±standard deviation marginal bone loss was 0.62 ±0.86 mm, and marginal bone loss did not differ significantly between axial and tilted implants (P>.05). Mechanical complications were detected in 55 (37.7%) definitive prostheses; biologic complications were detected in 318 (49.5%) implants. Smokers had a significantly lower survival rate than nonsmokers (odds ratio: 6.880, P=.013). Bruxers had a significantly higher incidence of mechanical complications than nonbruxers (P<.001).

CONCLUSIONS

The immediate loaded fixed complete denture supported by implants is a suitable treatment option for edentulous patients with a history of periodontitis, with high survival implant rates. Smoking is a risk factor for implant failure. Bruxism may increase the incidence of mechanical complications with implant-supported fixed complete dentures, and the overall biologic complication incidence is comparatively high.

Tooth preservation vs. extraction and implant placement in periodontally compromised patients: A systematic review and analysis of studies

PURPOSE

The aim of this systematic review was to identify studies with a minimum of 5-years follow-up, reporting on the management of periodontally compromised teeth with either extraction and subsequent implant placement or teeth preservation with conventional periodontal treatment and application of regenerative procedures. The outcomes of these two approaches, based on clinical and radiographic data and the incidence of tooth- and implant-loss, were also investigated.

MATERIAL AND METHODS

A systematic search for studies reporting on clinical and radiographic outcomes of periodontal treatment or replacement of periodontally compromised teeth with implants was conducted in 3 electronic databases, followed by a hand-search in 8 journals. Only randomized controlled trials (RCTs), cohort studies, and case series with prospective design were included.

RESULTS

The initial search resulted in 1080 papers. After the first two screenings, 24 publications were selected for inclusion in this systematic review. The treatment protocols for the teeth preservation group contained nonsurgical and/or surgical periodontal treatment with or without regeneration procedures. The implant studies included extraction of periodontally involved teeth and implant placement with or without bone and soft tissue augmentation, followed by restoration with fixed dental prostheses (FDPs). Survival rates ranged between 81.8% and 100% in the tooth retention group, and between 94.8% and 100% in the implant group. In the extraction group, no complications were reported for 76.09% of the implants. Similarly, no complications were reported for 86.83% of the tooth retention group. The lack of standardized comparable studies prohibited conduction of a metaanalysis.

CONCLUSION

Both treatment approaches, treatment of periodontally compromised teeth, or tooth extraction followed by implant placement, present high survival rates. The application of bone regeneration techniques improves the long-term prognosis of periodontally involved teeth. Hence, treatment of periodontally involved teeth with subsequent application of a rigorous maintenance protocol can be a viable alternative for a number of years, before proceeding to extraction and replacement with dental implants. More well-designed randomized controlled trials are needed in order to draw definite conclusions on the subject.

A Retrospective Analysis of Biological Complications of Dental Implants

Methods

A retrospective analysis of patients aged ≥18 years and having dental implants placed at Dubai Health Authority in 2010. Relevant information related to systemic-, patient-, implant-, site-, surgical- and prosthesis-related factors were collected. The strength of association between the prevalence of peri-implant mucositis and peri-implantitis and each variable was measured by chi-square analysis. A binary logistic regression analysis was performed to identify possible risk factors.

Results

A total of 162 patients with 301 implant-supported restorations were included in the study. The age of the patients ranged between 19 and 72 with a mean age of 46.4 ± 11.7 years. The prevalence of peri-implant mucositis at the patient and implant levels were 44.4% and 38.2%, respectively. For peri-implantitis, the prevalence at the patient level was 5.6%, while the prevalence at the implant level was 4.0%. The binary logistic regression identified three risk factors (smoking habits, histories of treated periodontitis and lack of peri-implant maintenance) for peri-implantitis.

Conclusion

Within the limitations of this study, smoking habits, history of treated periodontitis and lack of peri-implant maintenance were significant risk factors for peri-implantitis. Early detection of these factors would ensure appropriate planning and care of patients at high risk of developing peri-implant diseases.

Timing selection for loosened tooth fixation based on degree of alveolar bone resorption: a finite element analysis

Objective

This study aimed to evaluate timing of fixation to retard bone absorption using finite element analysis(FEA).

Methods

Volunteer CT images were used to construct four models of mandibles with varying degrees of alveolar bone resorption. By simulating occlusal force loading, biomechanical analysis was made on the periodontal membrane, tooth root and surrounding bone (both cancellous and cortical) of mandibular dentition.

Results

The von Mises stress value of the periodontal structures was positively related with the degree of alveolar bone resorption, and the von Mises stress at the interface between the periodontal membrane and tooth root was increased significantly in moderate to severe periodontitis models. The von Mises stress at the interface between the periodontal cortical bone and cancellous bone was increased significantly in the severe periodontitis model. And the von Mises stress value with oblique loading showed significantly higher than vertical loading.

Conclusion

Teeth with moderate to severe periodontitis, loosened tooth fixation can be used to retard bone absorption.

A prospective, multicentre study of 6-mm short implants in posterior alveolar bone supporting splinted crowns: A 5-year follow-up study

AIM

To evaluate the clinical and radiographic outcomes of 6-mm short implants, placed in the posterior jaws and supporting splinted crowns, at 5 years after early loading.

MATERIALS AND METHODS

Forty-five patients with 95 implants (diameter: 4 mm; length: 6 mm) were enrolled at three centres. Two to three implants were placed in either the maxillary or the mandibular posterior region in each patient and restored with screw-retained splinted crowns at 6 weeks later. Clinical and radiographic outcomes were evaluated at implant placement, at loading, and at 6, 12, 24, 36, and 60 months after loading. Biological and mechanical complications were recorded. Marginal changes in bone level in relation to clinical parameters were evaluated using a generalized linear mixed model.

RESULTS

During the 5 years of follow-up, the mean change in the marginal bone level (MBL) was 0.04 ± 0.14 mm. Four implants in four patients were lost before loading, one implant in one patient was lost at the 5-year follow-up, and two patients were lost to follow-up. The survival and success rates were 88.4% (38/43) at the patient level. The incidence rates of peri-implant mucositis and peri-implantitis were 29.4% and 7.0%, respectively. The rate of technical complications was 14.0%.

CONCLUSIONS

Over a 5-year period, 6-mm short implants supporting early loaded splinted crowns in maxillary or mandibular posterior regions showed stable MBLs and acceptable technical and biological complication rates.

Microbiota analysis of peri-implant mucositis in patients with periodontitis history

OBJECTIVES

To investigate the bacterial diversity in peri-implant plaques and the effect of periodontitis history on the occurrence of peri-implant mucositis.

MATERIALS AND METHODS

Three groups of subgingival plaques were collected from peri-implant sulci in the first molar area. The three groups included healthy implants in patients without periodontitis (NH implant), healthy implants in patients with periodontitis history (PH implant), and peri-implant mucositis implants in patients with periodontitis history (PM implant). Subgingival plaques in periodontal pockets of contralateral natural first molars were also collected. Bacterial DNA was extracted and the V4 region of the 16S rDNA sequence was amplified and sequenced on an Illumina HiSeq platform. The operational taxonomic units obtained from amplicon sequencing were used to analyze the prevalence and identity of bacteria based on public databases and advanced techniques.

RESULTS

Analysis of similarities indicated a significant difference in bacterial structures between the NH implant and PM implant groups. Additionally, a significantly higher relative abundance of the genera Actinomyces and Streptococcus was found in the samples of the NH implant group. The genera Fusobacterium and Prevotella could be considered as potential biomarkers for peri-implant mucositis. Moreover, more gram-negative anaerobic bacteria (Porphyromonas and Prevotella) were detected in the samples from patients with periodontitis history.

CONCLUSIONS

The increased accumulation of Fusobacterium and Prevotella is associated with a higher risk of peri-implant mucositis. In addition, patients with periodontal history may be more likely to develop peri-implant mucositis.

CLINICAL RELEVANCE

The increase in periodontal pathogens and the decrease in health-associated bacteria in patients with periodontitis history may be more likely to develop peri-implant mucositis. These results provide a bacteriological basis for the prevention and treatment of peri-implant mucositis in patients with periodontitis history.

Systematic review on the association between genetic polymorphisms and dental implant-related biological complications

OBJECTIVES

The aim of this systematic review was to evaluate the association between specific genetic polymorphisms and dental implant-related biological complications in patients having a follow-up period of at least 12-months post-loading.

MATERIAL AND METHODS

A sensitive search strategy was developed to identify implant-related genetic-association studies. This was performed by searching five databases. A three-stage screening (titles, abstract, full text) was carried out in duplicate and independently by two reviewers. Assessment was carried out according to the suggested scale for quality assessment of periodontal genetic-association studies and adapted to genetic analyses of implant-related studies leading to an overall final score 0-20 based on the summation of positive answers.

RESULTS

The initial search resulted in 1838 articles. Sixty-seven full-text articles were assessed for eligibility and four studies met the defined inclusion criteria. IL-6 G174C, TNF-α -308, IL-1A-889 and IL-1B+3954 and CD14-159 C/T polymorphisms were evaluated. The quality assessment scores ranged from 6 to 11 positive answers from out of a maximum score of 20. The great heterogeneity among the studies did not allow a meta-analysis.

CONCLUSIONS

The published evidence on genetic predisposition and implant biologic complications is limited. The small number of identified studies evaluating the association between genetic polymorphisms and peri-implant disease presented methodological and reporting inadequacies. Thus, the potential link between genetic polymorphisms and biological complications should be further investigated and clarified through well-designed clinical studies on adequately powered and appropriately included study populations.

Efficacy and risks of tooth-supported prostheses in the treatment of partially edentulous patients with stage IV periodontitis. A systematic review and meta-analysis

AIM

The aim was to evaluate the efficacy and effectiveness of tooth-supported fixed prostheses in partially edentulous patients with stage IV periodontitis.

MATERIAL AND METHODS

Randomized and controlled clinical trials (RCTs and CCTs) and prospective/retrospective cohort studies or case series were searched in three databases. Survival rate of abutment teeth was considered the primary outcome. Meta-analyses were performed whenever possible.

RESULTS

Twenty-four publications were included. No RCTs or CCTs compared the efficacy of tooth-supported fixed prostheses between patients with severe periodontitis or non-periodontitis patients. Most of the data retrieved were derived from case series. The incidence of abutment-tooth loss after a follow-up period from 2 to 35.4 years was low (n = 17 studies; weighted mean incidence (WMI) = 4.8%; confidence interval (CI) [3.2, 6.5]). The corresponding figure for prostheses failure was WMI = 6.9% (n = 18; 95% CI [4.1, 9.7]). Technical complications seemed to be more frequent than biological complications (caries, endodontic failure, root fracture, etc.). Periodontal outcomes tended to remain stable over time.

CONCLUSION

Tooth-supported fixed prostheses seemed to be a valid treatment approach to restore masticatory function in patients with stage IV periodontitis once periodontal therapy has been accomplished. However, the comparative efficacy of this treatment among periodontitis and non-periodontitis patients is unclear due to the absence of clinical trials.

Efficacy of tooth-supported compared to implant-supported full-arch removable prostheses in patients with terminal dentition. A systematic review

AIMS

To compare tooth- (TSRP) and implant-supported (ISRP) removable prostheses in terms of abutment and prosthesis survival (PICO 1) and estimated cumulative survival of teeth/implants and prostheses (PICO 2) at ≥12-month post-prosthesis delivery in patients with stage IV periodontitis.

MATERIALS AND METHODS

Five databases were searched to identify RCTs, CCTs, single arms, prospective cohort studies, case series and retrospective studies. Duplicate screening was performed, and ranges for abutment and prosthesis survival were calculated.

RESULTS

Twenty-six studies were included in the qualitative assessment. Only one study with critical risk of bias comparing the two treatment modalities reported similar survival rates at 2 years. Overall, prospective studies on ISRPs indicated an implant survival rate ranging from 96.4% to 100% and a prosthesis survival rate of 100% with a follow-up from 12 to 54 months. Prospective studies on TSRPs indicated a tooth survival ranging from 85.71% to 100% at 1- to 10-years follow-up.

CONCLUSIONS

The available evidence is of poor quality, and it does not allow to make robust conclusions on the efficacy of these rehabilitations in stage IV periodontitis patients. Particularly for TSRPs, careful patient selection is crucial and a certain number of biological and prosthetic complications should be expected.

Evaluation of the implant disease risk assessment (IDRA) tool: A retrospective study in patients with treated periodontitis and implant-supported fixed dental prostheses (FDPs)

Aim

To evaluate the Implant Disease Risk Assessment (IDRA) tool for the prediction of peri‐implantitis in treated periodontitis patients with implant‐supported fixed dental prostheses (FDPs) after at least 5 years of function.

Material and methods

From the patient pool of implant patients enrolled in a regular supportive periodontal therapy programme (SPT) for at least 5 years, 239 patients were screened. Eighty patients met the inclusion criteria and underwent evaluation through the criteria of the IDRA tool. Areas under the curve (AUCs) for receiver operating characteristic (ROC) curves including 95% confidence intervals were estimated.

Results

Seventy‐nine patients (43 males and 36 females, 8 smokers), aged on average 59.0 years (range: 40–79 years) at baseline (i.e. FDP delivery) were analysed. The calculated IDRA‐risk was in 34 patients (42.5%) a moderate risk, while 45 patients (56.3%) were considered at high IDRA‐risk. One patient categorized at low IDRA‐risk was excluded from the analysis.

The AUC was 0.613 (95% CI: 0.464–0.762) if the IDRA‐risk was associated with prevalence of peri‐implantitis at the most recent follow‐up. Peri‐implantitis was diagnosed in 4 patients (12%) at moderate and in 12 patients (27%) at high IDRA‐risk, respectively. The calculated odds ratio for developing peri‐implantitis in patients with high IDRA‐risk compared with patients with moderate IDRA‐risk was 2.727 with no statistically significant difference between the two groups (95% CI: 0.793–9.376).

Conclusion

Within the limitations of the present retrospective study, the IDRA algorithm might represent a promising tool to assess patients at moderate or high risk of developing peri‐implantitis.

Association between periodontitis treatment outcomes and peri-implantitis: A long-term retrospective cohort study

OBJECTIVES

Retrospectively evaluate the association of periodontal treatment outcomes and the prevalence of peri-implant diseases around tissue-level implants.

MATERIALS AND METHODS

Eighty-six patients with 260 tissue-level implants attending supporting periodontal and implant therapy for more than 3 years were evaluated. Clinical and radiographic periodontal and implant data were recorded at initial examination (T0), before implant placement (T1) and at final re-examination (T2). Two definitions of peri-implantitis severity, PIBE and PIKA, were used corresponding to the presence of periodontal pocket ≥5 mm or ≥6 mm with bleeding on probing or suppuration and radiographic signs of a bone level ≥2 mm, or ≥3 mm during implant follow-up, respectively. Analyses were performed at patient level.

RESULTS

The mean implant follow-up per patient was 9.4 years and 38.0% of patients had implant for at least 10 years. Two implants were lost due to peri-implantitis. The prevalence of patients with PIKA and PIBE was 15.1% and 12.8%, respectively. Residual periodontal pockets, clinical attachment loss and bone loss/age at T2 were more pronounced in patients with PIKA and PIBE. Cox regression analysis adjusted with the number of implants per patient showed that residual pockets at T1 were independently associated with PIKA and PIBE. Initial diagnosis of severe periodontitis was associated with PIBE incidence.

CONCLUSIONS

The present study showed that periodontal conditions before implant placement are a risk indicator for peri-implantitis incidence. During implant follow-up, the severity of periodontal status appeared to be a reliable indicator of patient susceptibility to peri-implantitis.

Evaluation of Implant Survival by Analysing Dental Panoramic Radiographs: 10-Year Retrospective Study

Background/Aim: Panoramic radiographs have been used widely for pre-implant evaluation and the preparation of treatment protocols. Panoramic radiography is often the first choice method for the implant placements because it gives information on the overall shape of the jaws, the position of the maxillary sinus floor and the nasal cavity floor, and vertical position of the mandibular canal and the mental foramen in relation to dental implants. The specific aim of the present study was to evaluate 10-year survival rate of dental implants by analysis of dental panoramic radiographs.

Material and Methods: This retrospective study was conducted on 507 panoramic radiographs of 156 implant patients. Initial oral health status, proceedings of Restorative/Endodontic treatments before implant placement, missing number of teeth and edentulism types, finalization of implant related prosthetic treatments during controls, implant quality scorings at baseline/ controls and implant fails were analyzed.

Results: The study results reveal statistically significant difference between the performed R/E treatment rates, according to the need for R/E treatments (p= 0.008). During the initial radiograph 96.1% of the implants were successful and 3.9% had satisfactory survival. At last control 86% of the implants were successful, 10.3% had satisfactory survival, 1% had impairment in survival and 2.8% were unsuccessful. The change in the last control compared to the initial radiograph is statistically significant (p= 0.000) regarding satisfactory survival.

Conclusions: Long-term implant survival is not significantly affected by gender, age, type of edentulism, the presence of periodontal disease, R/E treatment needs, implant location, prosthesis type, and the presence of multiple implants.

Evaluation of peri-implant tissues condition after 10-15 years of loading in treated chronic periodontitis patients attending a private practice setting: A retrospective study

OBJECTIVES

To retrospectively evaluate the conditions of the peri-implant tissues in treated patients with chronic periodontitis (CP) and in patients without chronic periodontitis (noCP).

MATERIALS AND METHODS

A chart review was used to evaluate 267 implants, 134 placed in 42 CP treated patients and 133 placed in 46 noCP patients. The primary outcome was to evaluate the condition of the peri-implant tissues (health, peri-mucositis, and peri-implantitis). The secondary outcome was to evaluate the possible association of some variables, such as, Plaque Index (PI), Bleeding Index (BI), probing pocket depth (PD), bleeding on probing (BoP), bone level (BL), loading time, type of implant placement and loading protocol, type of prosthesis, type of bone, implant manufacturer, and implant diameter and length, with the implant health condition.

RESULTS

The analysis of patient files revealed that after 10-15 years of loading (mean loading time 13.4 ± 2.07 years), six noCP patients (13%) experienced implant loss with a total of nine implants (6.7%) lost. The remaining 124 implants were classified: 54 (43.5%) as healthy, 45 (36.3%) with peri-implant mucositis, and 25 (20.2%) with peri-implantitis. Twelve CP subjects (28.5%) experienced implant loss with a total of 19 implants (14.1%) lost. The remaining 115 implants were classified: 34 (29.5%) as healthy, 40 (34.7%) with peri-implant mucositis and 41 (35.6%) with peri-implantitis. Compared with noCP subjects, only treated CP subjects with recurrent periodontal disease (RPD) showed differences statistically significant (p < .05).

CONCLUSIONS

After 10-15 years of loading, in CP patients treated in a private practice setting, most implants (70.1%) were classified with some type of peri-implant inflammation. In patients with RPD, a higher tendency for implant loss and peri-implant biologic complications was found.

Vertical Guided Bone Regeneration in the Rabbit Calvarium Using Porous Nanohydroxyapatite Block Grafts Coated with rhVEGF165 and Cortical Perforation

Introduction

Vertical bone augmentation without osseous walls to support the stability of clots and bone grafts remains a challenge in dental implantology. The objectives of this study were to confirm that cortical perforation of the recipient bed is necessary and to evaluate whether nanohydroxyapatite (nHA) block grafts coated with recombinant human vascular endothelial growth factor₁₆₅ (rhVEGF₁₆₅) and cortical perforation can improve vertical bone regeneration.

Materials and Methods

We prepared nHA blocks coated with or without rhVEGF₁₆₅ on the rabbit calvarium through cortical perforation, and designated the animals as the nonperforated group (N-nHA), rhVEGF₁₆₅ group (NV-nHA), perforated group (P-nHA) and rhVEGF₁₆₅ on perforated group (PV-nHA). Micro-computed tomography (micro-CT) and fluorescence microscopy were selected to evaluate parameters of vertical bone regeneration at 4 and 6 weeks.

Results

The ratio of the newly formed bone volume to the titanium dome volume (BV/TV) and the bone mineral density (BMD) were significantly higher in the PV-nHA group than in the N-nHA group at 4 and 6 weeks, as determined using micro-CT. The fluorescence analysis showed slightly greater increases in new bone regeneration (NB%) and vertical height (VH%) gains in the P-nHA group than in the N-nHA group. Greater increases in NB% and VH% were observed in groups treated with rhVEGF₁₆₅ and perforation than in the blank groups, with significant differences detected at 4 and 6 weeks (N-nHA compared with PV-nHA, p<0.05). A greater VH% that was observed at the midline of the block in the PV-nHA group than in the other three groups at both time points (0.75±0.53% at 4 weeks and 0.83±0.42% at 6 weeks).

Conclusion

According to the present study, cortical perforation is necessary and nHA blocks coated with rhVEGF₁₆₅ and decoration could work synergistically to improve vertical bone regeneration by directly affecting primary osteoblasts and promoting angiogenesis and osteoinduction.

Periodontal regeneration versus extraction and dental implant or prosthetic replacement of teeth severely compromised by attachment loss to the apex: A randomized controlled clinical trial reporting 10-year outcomes, survival analysis and mean cumulative cost of recurrence

Background

Periodontal regeneration can change tooth prognosis and represents an alternative to extraction in teeth compromised by severe intra‐bony defects. The aim of this study was to compare periodontal regeneration (PR) with tooth extraction and replacement (TER) in a population with attachment loss to or beyond the apex of the root in terms of professional, patient‐reported and economic outcomes.

Methods

This was a 10‐year randomized controlled clinical trial. 50 stage III or stage IV periodontitis subjects with a severely compromised tooth with attachment loss to or beyond the apex were randomized to PR or TER with either an implant‐ or a tooth‐supported fixed partial denture. Subjects were kept on a strict periodontal supportive care regimen every 3 months and examined yearly. Survival and recurrence analysis were performed.

Results

88% and 100% survival rates were observed in the PR and TER groups. Complication‐free survival was not significantly different: 6.7–9.1 years for PR and 7.3–9.1 years for TER (p = .788). In PR, the observed 10‐year attachment gain was 7.3 ± 2.3 mm and the residual probing depths were 3.4 ± 0.8 mm. Recurrence analysis showed that the 95% confidence interval of the costs was significantly lower for PR compared with TER throughout the whole 10‐year period. Patient‐reported outcomes and oral health‐related quality‐of‐life measurements improved in both groups.

Conclusions

Periodontal regeneration can change the prognosis of hopeless teeth and is a less costly alternative to tooth extraction and replacement. The complexity of the treatment limits widespread application to the most complex cases but provides powerful proof of principle for the benefits of PR in deep intra‐bony defect.

Changes of clinical parameters at implants: A retrospective comparison of implants versus natural teeth over 5 years of supportive periodontal therapy

OBJECTIVES

To compare clinical parameters of implants versus natural teeth over a period of 5 years during supportive periodontal therapy (SPT).

MATERIAL AND METHODS

A total of 421 SPT patients were screened for implants (I) and corresponding control teeth (C). Data (patient level [_P ]: sex, age, smoking status, systemic diseases, adherence, oral hygiene indices, mean probing depth [PD]_P , bleeding on probing [BOP]_P , periodontal risk profile; implant/control tooth level [_I/C ]: PD_I/C , BOP_I/C ; site level at implants [_SITE ]: position, dental arch, aspect, BOP_SITE ) were assessed at the first SPT session where the implant was probed (T1) and 5 years later (T2). The influence of patient and implant/control-related factors on PD_I/C /BOP_I/C was tested (linear mixed model) as well as the influence of site-specific factors on the PD_SITE change (multilevel regression).

RESULTS

A total of 70 patients (151 implants) were included. Mean PD_I was 2.75 ± 0.85 mm (T1) and 2.87 ± 0.79 mm (T2). Mean PD_C was 2.42 ± 0.66 mm (T1) and 2.49 ± 0.71 mm (T2). BOP_I increased from 8.62 ± 15.01% (T1) to 24.06 ± 26.79% (T2) and BOP_C from 9.97 ± 17.78% (T1) to 15.52 ± 22.69% (T2). The differences between implants and controls were significant for BOP (p = .0032). At T2, BOP_I/C was associated with periodontal risk (p = .0351). The site-specific analysis revealed an association of BOP_SITE at T1 with the progression of PD_SITE (p = .0058).

CONCLUSIONS

Probing depths of implants and controls seem to change similarly during SPT but retention of inflammation-free conditions at implants appears to be more difficult compared to natural teeth. Patients with a high-risk profile appear to have an increased susceptibility for BOP around implants, and BOP at implants seems to be a predictor for further PD increase.

Evaluation of peri-implant marginal tissues around tissue-level and bone-level implants in patients with a history of chronic periodontitis

OBJECTIVE

To evaluate clinical and radiographic characteristics in peri-implant marginal tissues in patients with a history of chronic periodontitis, rehabilitated using tissue-level or bone-level implants.

MATERIAL AND METHODS

Using a split-mouth design, 20 patients with a history of chronic periodontitis were selected and received two different implants, tissue-level group (n = 20) and the bone-level group (n = 20). Peri-implant probing depth, relative peri-implant mucosal margin position, relative peri-implant clinical attachment level, peri-implant plaque index and peri-implant bleeding on probing were evaluated at prosthesis installation, 1, 3, 6, 12 and 24 months after implant loading. Radiographic marginal bone level was evaluated at implant insertion, prosthesis installation, 6 and 24 months after implant loading.

RESULTS

The mean difference of peri-implant marginal bone resorption from implant installation to 24 months in function was 0.75 ± 1.12 mm for the tissue-level group and 0.70 ± 0.72 mm for the bone-level group. No statistically significant difference was found between groups at all assessment periods for clinical and radiographic peri-implant evaluation.

CONCLUSION

Under a rigid supportive therapy, both approaches performed likewise regarding clinical and radiographic parameters for rehabilitation of patients with a history of chronic periodontitis.

Interim tissue changes following connective tissue grafting and two-stage implant placement. A randomized clinical trial

AIM

To determine tissue changes at implants placed either conventionally or in combination with a connective tissue graft (CTG).

MATERIALS AND METHODS

Forty-eight partially edentulous subjects were randomized into two treatment Groups, and 46 completed the study. Group-A (N_A   = 23) received crestal implant placement. In Group-B (N_B   = 23), a CTG harvested from the palate was stabilized over the implant neck. At the time of implant placement (T0), Groups were categorized as having thin mucosa ≤ 2.5 mm at the surgical site (N_{S ubgroup- AI}   = 12, N_{S ubgroup- BI}   = 11) or thick mucosa > 2.5 mm (N_{S ubgroup- AII}   = 11, N_{S ubgroup- BII}   = 12). Mucosa thickness, width of keratinized tissue (WKT), crestal bone levels and relative bone thickness were determined at T0 and at the two-stage surgery (T1).

RESULTS

At T1, on the alveolar crest, mucosa thickness significantly decreased in the thick mucosa Subgroups (-AII/-BII, both p = 0.001), but increased at thin mucosa grafted sites (p = 0.049). No significant changes were noted in the WKT for either group. Thin mucosa grafted Subgroups (-AI/-BI) demonstrated significant decreases in crestal bone levels (both p ≤ 0.008). Crestal relative bone thickness decreased in all Subgroups (p ≤ 0.027 for significant changes).

CONCLUSIONS

Connective tissue grafting resulted in smaller reductions of mucosa thickness on the alveolar crest and appeared to have the greater effects at sites with initially thin mucosa.

Are There Contraindications for Placing Dental Implants?

There are few absolute contraindications to dental implant placement. Relative contraindications include cognitive decline, American Society of Anesthesiology patient status IV or higher categories, or medical conditions that may jeopardize the life or lifespan of the patient. Precautions for placing dental implants should be viewed with respect to the evidence-based exposures that can contribute to risk of failure, including but not limited to local, behavioral, and medical factors. Risk for dental implant failure increases in association with (1) past history of periodontal disease, (2) bruxism, (3) smoking, and (4) radiation therapy.

Predicting peri-implant disease: Chi-square automatic interaction detection (CHAID) decision tree analysis of risk indicators

BACKGROUND

Further validation of the risk indicators / predictors for peri-implant diseases is required to allow clinicians and patients to make informed decisions and optimize dental implant treatment outcomes. The aim of this study was to build prediction models, using Chi-square automatic interaction detection (CHAID) analysis, to determine which systemic-, patient-, implant-, site-, surgical- and prostheses-related risk indicators had more impact on the onset of peri-implant diseases.

METHODS

A retrospective analysis of 200 patients who received implant-supported prostheses between 1998 and 2011 was conducted to evaluate the prevalences and risk indicators for peri-implant mucositis and peri-implantitis. The data were further analyzed using CHAID to produce two predictive models.

RESULTS

The prevalence of peri-implant mucositis was 20.2% and 10.2% for patients and implants, respectively, while the prevalence of peri-implantitis was 10.1% at the patient level and 5.4% at the implant level. CHAID decision tree analysis identified three predictors (history of treated periodontitis, absence of regular supportive peri-implant maintenance, and use of bone graft) for peri-implant mucositis and three predictors (smoking, absence of regular supportive peri-implant maintenance, and placement of ≥2 implants) for peri-implantitis.

CONCLUSIONS

Within the limitations of this study, CHAID decision tree analysis identified the most plausible risk indicators and provided two predictive models for use in a particular university setting that would allow early detection and ensure appropriate care and maintenance of patients at high risk of peri-implant diseases.

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 nomogram prediction of peri-implantitis in treated severe periodontitis patients: A 1-5-year prospective cohort study

BACKGROUND

No nomogram of peri-implantitis was reported before which is valuable for risk-estimating, clinical decision-making, and better-patients-communicating.

PURPOSE

To identify the risk indicators and develop a nomogram prediction model of peri-implantitis in treated severe periodontitis patients.

MATERIALS AND METHODS

A prospective study was conducted on 100 patients with 214 implants. Periodontal and peri-implant parameters were evaluated at implant surgery procedure (T1), and at follow-up (T2). Risk factors were analyzed by logistic regression analyses with generalized estimating equations. Nomogram was developed and the discriminatory ability of the model was analyzed.

RESULTS

The incidence of peri-implantitis at patient-level and implant level were 16% and 11.2% respectively, with no implant lost. The variables associated with peri-implantitis were the PD_T1  ≥ 6 mm (%) > 10%, the implant position, length, and diameter after adjusting for covariates. A nomogram prediction model of peri-implantitis were developed with factors of PD _T1  ≥ 6 mm (%) > 10% and implant placed in posterior. The area under the ROC curves of stepwise model was 0.794.

CONCLUSIONS

The residual pockets and implants position were identified as predictors for the peri-implantitis. The nomogram can be used to estimate the risk of peri-implantitis in treated severe periodontitis patients.

Peri-implantitis: A Comprehensive Overview of Systematic Reviews

The objective of this systematic review was to perform a comprehensive overview of systematic reviews and meta-analyses pertaining to peri-implantitis in humans, including the prevalence and incidence, the diagnostic findings, microbial findings, effects of systemic diseases, and treatment of peri-implantitis. Electronic databases were searched for systematic reviews and meta-analyses of peri-implantitis. In view of the limitations of the included systematic reviews, the outcome of this overview suggested that (1) occurrence of peri-implantitis was higher in patients with periodontitis, in patients who smoke, and after 5 years of implant function; (2) the microbial profile of peri-implantitis was different from periodontitis; (3) risk for peri-implantitis was higher in patients with uncontrolled diabetes and cardiovascular disease; (4) there was no strong evidence to suggest the most effective treatment intervention for peri-implantitis, although most peri-implantitis treatments can produce successful outcomes; and (5) postimplant maintenance may be crucial in patients with a high risk of peri-implantitis.

Should implants be considered for patients with periodontal disease?

Dental implants are seen as a good option for replacing missing teeth. The success and survival rates for implants are very high. Concerns are developing about the problem of peri-implantitis. The reports of its prevalence vary but it is noted that the presence of periodontal disease is a risk factor. The issue of peri-implantitis was raised in the House of Lords in 2014. Complaints relating to implants is on the rise with the General Dental Council. Placement of implants in patients with periodontal disease is not a treatment that should be done without a full periodontal assessment and stabilisation of periodontal disease first. This review considers the risk of placing implants in patients with aggressive and chronic periodontitis.

Scanning Electron Microscope (SEM) Evaluation of the Interface between a Nanostructured Calcium-Incorporated Dental Implant Surface and the Human Bone

Purpose. The aim of this scanning electron microscope (SEM) study was to investigate the interface between the bone and a novel nanostructured calcium-incorporated dental implant surface in humans. Methods. A dental implant (Anyridge^®, Megagen Implant Co., Gyeongbuk, South Korea) with a nanostructured calcium-incorporated surface (Xpeed^®, Megagen Implant Co., Gyeongbuk, South Korea), which had been placed a month earlier in a fully healed site of the posterior maxilla (#14) of a 48-year-old female patient, and which had been subjected to immediate functional loading, was removed after a traumatic injury. Despite the violent trauma that caused mobilization of the fixture, its surface appeared to be covered by a firmly attached, intact tissue; therefore, it was subjected to SEM examination. The implant surface of an unused nanostructured calcium-incorporated implant was also observed under SEM, as control. Results. The surface of the unused implant showed a highly-structured texture, carved by irregular, multi-scale hollows reminiscent of a fractal structure. It appeared perfectly clean and devoid of any contamination. The human specimen showed trabecular bone firmly anchored to the implant surface, bridging the screw threads and filling the spaces among them. Conclusions. Within the limits of this human histological report, the sample analyzed showed that the nanostructured calcium-incorporated surface was covered by new bone, one month after placement in the posterior maxilla, under an immediate functional loading protocol.

Microbiome and Microbial Biofilm Profiles of Peri-Implantitis: A Systematic Review

BACKGROUND

This systematic review assesses microbiologic profiles of peri-implantitis, periodontitis, and healthy implants based on studies that evaluated microbial biofilms and entire microbiomes to establish their similarities and differences.

METHODS

The Medical Literature Analysis and Retrieval System Online via PubMed, Excerpta Medica Database, and Cochrane Central Register of Controlled Trials, were searched without language restrictions through July 30, 2016. Observational studies that evaluated microbial profiles or entire microbiomes of peri-implantitis compared with healthy implants or periodontitis were considered eligible for inclusion. A descriptive summary was created to determine quantity of data and interstudy variations.

RESULTS

Of 126 potentially eligible articles, 26 were included in this study. Twenty-one of these articles evaluated the microbiologic profile of peri-implantitis versus healthy implants or periodontitis using conventional microbiologic techniques. Five articles evaluated the entire microbiome using genomic sequencing. Teeth with periodontitis, healthy implants, or implants with peri-implantitis were colonized by periodontal microorganisms. Porphyromonas gingivalis and especially Prevotella intermedius/nigrescens were often identified at peri-implantitis sites. Peri-implantitis sites were also colonized by uncultivable asaccharolytic anaerobic Gram-positive rods and anaerobic Gram-negative rods, which were not frequently identified in teeth with periodontitis or healthy implants. Opportunistic microorganisms were not found very frequently in peri-implantitis sites.

CONCLUSIONS

Peri-implantitis represents a heterogeneous mixed infection that includes periodontopathic microorganisms, uncultivable asaccharolytic anaerobic Gram-positive rods and other uncultivable Gram-negative rods, and, rarely, opportunistic microorganisms such as enteric rods and Staphylococcus aureus. Sequencing methods that evaluate the entire microbiome improve identification of microorganisms associated with peri-implantitis.

Identification of a discriminative metabolomic fingerprint of potential clinical relevance in saliva of patients with periodontitis using 1H nuclear magnetic resonance (NMR) spectroscopy

Periodontitis is characterized by the loss of the supporting tissues of the teeth in an inflammatory-infectious context. The diagnosis relies on clinical and X-ray examination. Unfortunately, clinical signs of tissue destruction occur late in the disease progression. Therefore, it is mandatory to identify reliable biomarkers to facilitate a better and earlier management of this disease. To this end, saliva represents a promising fluid for identification of biomarkers as metabolomic fingerprints. The present study used high-resolution ¹H-nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistical analysis to identify the metabolic signature of active periodontitis. The metabolome of stimulated saliva of 26 patients with generalized periodontitis (18 chronic and 8 aggressive) was compared to that of 25 healthy controls. Principal Components Analysis (PCA), performed with clinical variables, indicated that the patient population was homogeneous, demonstrating a strong correlation between the clinical and the radiological variables used to assess the loss of periodontal tissues and criteria of active disease. Orthogonal Projection to Latent Structure (OPLS) analysis showed that patients with periodontitis can be discriminated from controls on the basis of metabolite concentrations in saliva with satisfactory explained variance (R2X = 0.81 and R2Y = 0.61) and predictability (Q2Y = 0.49, CV-AUROC = 0.94). Interestingly, this discrimination was irrespective of the type of generalized periodontitis, i.e. chronic or aggressive. Among the main discriminating metabolites were short chain fatty acids as butyrate, observed in higher concentrations, and lactate, γ-amino-butyrate, methanol, and threonine observed in lower concentrations in periodontitis. The association of lactate, GABA, and butyrate to generate an aggregated variable reached the best positive predictive value for diagnosis of periodontitis. In conclusion, this pilot study showed that 1H-NMR spectroscopy analysis of saliva could differentiate patients with periodontitis from controls. Therefore, this simple, robust, non-invasive method, may offer a significant help for early diagnosis and follow-up of periodontitis.

Outcomes of implant therapy in patients with a history of aggressive periodontitis. A systematic review and meta-analysis

OBJECTIVE

To investigate the outcomes of implant therapy in partially dentate patients treated for aggressive periodontitis (GAgP) in comparison to periodontally healthy (HP) and patients treated for chronic periodontitis (CP) utilizing radiographic and clinical parameters.

MATERIAL AND METHODS

An electronic search of databases, supplemented by hand searching, was conducted to identify relevant clinical studies. Sequential screenings at the title, abstract and full-text levels were performed independently and in duplicate. A random effects meta-analysis was conducted and bias corrected bootstrap 95 % confidence intervals were estimated for group comparisons.

RESULTS

The search strategy revealed a total of 899 results. After title screening, abstract scanning, and full-text reading, seven articles fulfilled the inclusion criteria. The 3-year survival rate for CP and HP patients was 100 % while in GAgP subjects, the respective value was 97.98 %; this difference being statistically significant. The 3-year mean marginal bone loss (MBL) was 1.07 mm for the GAgP group, 0.47 mm for the CP group, and 0.69 mm for the HP group. A significant difference between the GAgP and CP groups was identified (p < 0.05). The weighted mean differences of MBL concerning the above groups were also calculated and examined for statistical significance in both 1 and 3 years.

CONCLUSIONS

The 3-year survival rate and peri-implant marginal bone loss was found statistically significantly lower in GAgP subjects (SR 97.98 % vs 100 %) in comparison to HP and CP individuals.

CLINICAL RELEVANCE

The outcome of implant therapy in terms of survival rate and marginal bone loss is considered very important for the clinician in decision making when placing implants in patients with a history of aggressive periodontitis.

Impact of platform switching on inter-proximal bone levels around 8.5 mm implants in the posterior region; 5-year results from a randomized clinical trial

AIM

To assess the medium-term results of 8.5 mm implants supplied with a conventional platform-matched implant-abutment connection or a platform-switched design.

MATERIALS AND METHODS

Eighty patients with one or more missing teeth in the maxillary or mandibular posterior zone were randomly assigned for treatment with implants with a conventional (control group) or platform-switched (test group) implant-abutment connection. Follow-up visits were conducted 1 month, 1 year and 5 years after functional loading. Inter-proximal bone loss, assessed with standardized peri-apical radiographs, clinical parameters, survival of implants and satisfaction of patients were the outcome parameters studied.

RESULTS

After 5 years of loading, five of the 80 patients were lost to follow-up. The inter-proximal bone loss in the test group (0.38 ± 0.61 mm) was comparable to the bone loss in the control group (0.41 ± 0.47 mm; p = 0.201). Remarkably, bone loss has not progressed compared to the 1-year results. Implant survival, clinical parameters and satisfaction of the patients were favourable and comparable for the test and control group.

CONCLUSION

The 5-years results showed that inter-proximal bone resorption was minor and comparable around platform-matched and platform-switched implants, and implant survival, peri-implant health and patients' satisfaction were favourable.