Air powder waterjet technology using erythritol or glycine powders in periodontal or peri-implant prophylaxis and therapy: A consensus report of an expert meeting

OBJECTIVES

To attain a collective expert opinion on the use of air powder waterjet technology (APWT) with erythritol and glycine powders in the prophylaxis and therapy of periodontal and peri-implant diseases.

MATERIAL AND METHODS

In the first step, a modified one-round online Delphi survey including 44 five-point Likert scale questions was conducted among a group of 10 expert clinicians and researchers with thorough knowledge and experience in this topic. In the second step, the single questions and the survey results were discussed during a meeting, and consensus statements were formulated, respectively.

RESULTS

An agreement was reached on most items, especially opinions supporting glycine and erythritol powders as favorable with respect to efficiency, safety, and comfort. More scientific evidence is needed to support the improvement in clinical attachment on teeth and implants, especially when APWT with erythritol is used. In addition, APWT needs more long-term evaluation and studies in terms of microbiome/microbiological effects as well as effects on the inflammatory response on natural teeth and implants, also in light of a guided biofilm therapy concept.

CONCLUSIONS

In line with the expert opinions and supported by the evidence, it was concluded that the use of APWT with erythritol and glycine powders in nonsurgical periodontal and peri-implant therapy and prophylaxis is patient compliant and efficient.

Effect of Low-Level Laser Irradiation (810 nm) on the Proliferation and Differentiation of Osteoblast-Like Cells Cultured on SLA Titanium Discs Exposed to a Peri-implantitis Environment

Introduction: Elimination of inflammation and re-osseointegration are the major objectives of peri-implantitis therapy. Existing data, however, do not support any decontamination approach. Thus, the present in vitro study aims to assess whether the air-debriding decontamination method with erythritol powder restores the biocompatibility of infected titanium discs and to investigate the potent biomodulatory ability of diode laser (810 nm) irradiation to promote cell proliferation and differentiation of premature osteoblast-like cells (MG63) towards osteocytes. Methods: The experimental groups consisted of cells seeded on titanium discs exposed or not in a peri-implantitis environment with or without biomodulation. Infected discs were cleaned with airflow with erythritol powder. Cell cultures seeded on tricalcium phosphate (TCP) surfaces with or without biomodulation with a laser (810 nm) were used as controls. The study evaluated cell viability, proliferation, adhesion (SEM) at 24, 48 and 72 hours, and surface roughness changes (profilometry), as well as the effects of low-level laser therapy (LLLT) on ALP, OSC, TGF-b1, Runx2, and BMP-7 expression in MG63 cells' genetic profile on days 7, 14, and 21. Results: The MTT assay as well as the FDA/PI method revealed that cell proliferation did not show significant differences between sterile and decontaminated discs at any timepoint. SEM photographs on day 7 showed that osteoblast-like cells adhered to both sterile and disinfected surfaces, while surface roughness did not change based on amplitude parameters. The combination of airflow and LLLT revealed a biomodulated effect on the differentiation of osteoblast-like cells with regard to the impact of laser irradiation on the genetic profile of the MG63 cells. Conclusion: In all groups tested, osteoblast-like cells were able to colonize, proliferate, and differentiate, suggesting a restoration of biocompatibility of infected discs using airflow. Furthermore, photomodulation may promote the differentiation of osteoblast-like cells cultured on both sterile and disinfected titanium surfaces.

Systemic inflammatory markers following adjunctive Nd:YAG (1064 nm) laser irradiation to step 2 of periodontal therapy: a 12-month, randomized, controlled trial

OBJECTIVES

The aim of this study was to investigate whether the use of adjunctive Nd:YAG (1064 nm) laser irradiation to full-mouth scaling and root planing (FM-SRP) may offer additional benefit in the systemic inflammatory status of the patient, as depicted in a variety of systemic biomarkers over FM-SRP alone, up to 12 months after treatment.

MATERIALS AND METHODS

A total of 60 otherwise healthy stage III/IV periodontal patients were equally distributed in 3 groups. The control group received FM-SRP. In laser A group, 1 week after FM-SRP, Nd:YAG laser irradiation was delivered in periodontal pockets with PD ≥ 4 mm using specific settings (3 W, 150 mJ, 20 Hz, 100 μs). In laser B group Nd:YAG laser irradiation was delivered twice, 1 week after FM-SRP and 1 week later with different settings compared to laser A (2 W, 200 mJ, 10 Hz, 100 μs).

RESULTS

A significant reduction (p = 0.038) of IL-1β serum levels at the 6-month time point was observed for laser A group. IL-6 was found statistically significantly increased (p = 0.011) in the control group at the 6-week time point, whereas no difference was reported for the laser-treated groups (laser A, laser B).

CONCLUSIONS

The adjunctive use of Nd:YAG laser irradiation, prevented from IL-6 increase after FM-SRP, 6 weeks after treatment. Similarly, Nd:YAG laser irradiation (3 W, 150 mJ, 20 Hz,100 μs) was associated with significantly lower IL-1β levels, 6 months post-operatively.

CLINICAL RELEVANCE

Additional Nd:YAG laser application to FM-SRP may provide a potential beneficial effect on systemic inflammation.

TRIAL REGISTRATION NUMBER

ISRCTN26692900.

REGISTRATION DATE

09/06/2022.

Free titanium particles and P. gingivalis lipopolysaccharide create a potentially synergistical effect in a periimplantitis model

OBJECTIVE

Our aim was to examine the effect of titanium particles and lipopolysaccharide (LPS) from P. gingivalis on the inflammatory profile expression of human gingival fibroblasts (hGFs), cultured on rough titanium discs, in an in vitro peri-implantitis simulation.

DESIGN

Human gingival fibroblasts cultured on SLA and TCP surfaces were challenged with LPS, titanium particles or both. At 24, 48 and 72 h after treatment, MTT assay was performed to assess cell proliferation. FDA/PI staining was performed for the same time periods, in order to evaluate cell viability/apoptosis. At 5 and 7 days after the treatment, qPCR was performed to assess gene expressions of IL-6, IL-8 and COL1A1, as well as SEM on titanium discs.

RESULTS

All groups presented a significant increase of their population between the time periods of examination. Regarding the interleukin gene expression, the combination of LPS and particles significantly increased the levels of Interleukin-8. Treatment with LPS and particles also induced a significant increase of Interleukin-6 and collagen. FDA/PI microscopy has revealed several apoptotic cells in the treatment groups. SEM micrographs have shown the difficulty of hGFs to adhere on rough surfaces.

CONCLUSIONS

The combination of titanium particles and LPS significantly upregulated the expression of IL-6, IL-8 and Col-1a. It appears that particles may arouse similar reactions to the endotoxin, while synergistically intensifying it.

The necessity of administrating antibiotic prophylaxis to patients with diabetes mellitus prior to oral surgical procedures-a systematic review

BACKGROUND AND AIMS

Μany studies suggest the use of antibiotic prophylaxis (AP) as an appropriate preventive measure for patients with diabetes mellitus (DM) due to the increased possibility of an impaired wound healing and infections after surgical procedures in the oral cavity. Existing recommendations regarding antibiotic prophylaxis before surgical procedures are not definitive and are based on expert opinions. The purpose of this study was to review the available scientific data about the necessity of administrating AP as a preventive measure prior to oral surgical procedures.

METHOD

PubMed®, Scopus® και Cochrane Central Register of Controlled Trials (CENTRAL) were used as databases to search for published research. All articles were initially identified and classified based on the title and subsequently on their abstract. For the next level the full scientific paper was read and evaluated.

RESULTS

Overall, 22 articles were included in the study, of which 2 were systematic reviews, 2 cohort studies, 2 case-control studies, 1 case series, 8 case reports and 7 professional association publications.

CONCLUSIONS

In the scientific literature, there is a wide range of recommendations and inconsistency regarding the need to administer AP prior to surgical dental operations in patients with DM, while there is no scientific evidence demonstrating its' effectiveness as a precautionary measure. Both blood glucose level measurements and recent HbA1c measurement should be evaluated before any dental procedure. Poor regulation may result to life-threatening infections after tooth extraction. AP is recommended prior to the placement of dental implant. Randomized, controlled, clinical trials with large number of participants and greater variety of surgical dental procedures are needed.

The ever-changing landscape in modern dentistry therapeutics - Enhancing the emptying quiver of the periodontist

Introduction/Objectives

Periodontitis comprises of a wide range of inflammatory conditions of the gums leading to soft tissue damage and attachment loss. The initiation of periodontitis constitutes a rather complex disease pathogenesis which is based on pathogenic shifts of the oral microbiota combined with the host-microbiome interactions. The severity of the periodontitis is multifactorial depending on genetic, environmental, as well as host immunity factors.

Data and sources

To make an inclusive analysis on the periodontitis therapeutics, reading of the recent relevant literature was carried out using the MEDLINE/PubMed database, Google Scholar and the NIH public online database for clinical trials (http://www.clinicaltrials.gov).

Conclusions

Tackling the inflammation associated periodontal defects can be succeeded with conventional therapy or resective and regenerative treatment. To date, the mechanical removal of the supragingival and subgingival biofilm is considered the “gold standard” of periodontal therapy in combination with the use of antibacterial compounds. The antimicrobial resistance phenomenon tends to turn all the currently applied antibacterials into “endangered species”. Ongoing efforts through the conduct of clinical trials should be focused on understanding the advantages of modern approaches in comparison to traditional therapies.

Low Level Laser Therapy With an 810-nm Diode Laser Affects the Proliferation and Differentiation of Premature Osteoblasts and Human Gingival Fibroblasts In Vitro

Introduction: Photomodulation is a promising strategy for optimizing tissue healing, but its photomodulatory effects on the synergistic cellular metabolism of gingival and bony tissues remain largely unknown. The aim of the present study was to evaluate the photomodulatory effects of a diode laser (810 nm) on osteoblasts, HGFs and their co-cultures in vitro. Methods: Primary cultures of HGFs, cultures of immature osteoblastic cells (MG63) and their co-cultures were irradiated with a diode laser (810 nm), 15 J/cm². Cell cultures were examined for cellular proliferation (MTT assay), viability (FDA/PI staining) after 24, 48 and 72 hours and cell differentiation (qPCR of collagen type 1a - COL1a and alkaline phosphatase expressions - ALP) after 7 days. Results: Photomodulation with an 810-nm diode laser increased cell proliferation at all time points. COL1a gene expression increased both in HGF and co-cultures. ALP expression was up-regulated in osteoblastic cultures, but co-cultures with fibroblasts negated this response. Conclusion: The 810-nm diode laser positively affected cell proliferation and viability in all experimental groups. The statistically significant increased COL1a gene expression at 7 days after irradiation both in the irradiated HGF and co-cultures suggests that low-level laser therapy (LLLT) stimulated extracellular matrix (ECM) formation signaling in both cell types.

Dosage Effects of an 810 nm Diode Laser on the Proliferation and Growth Factor Expression of Human Gingival Fibroblasts

Introduction: A substantial amount of evidence supports the positive effect of photobiomodulation on the proliferation and differentiation of various cell types. Several laser wavelengths have been used for wound healing improvement, and their actual outcome depends on the settings utilized during irradiation. However, the heterogeneous wavelengths and laser settings applied in the existing literature make it difficult to draw solid conclusions and comparison of different studies. The aim of the present study is to evaluate and compare the effects of various doses of laser energy, provided by an 810 nm diode, on human gingival fibroblasts in terms of proliferation and expression of growth factors with a pivotal role in wound healing. Methods: Human gingival fibroblasts were cultured on plastic tissue culture and irradiated with 2, 4, 6 or 12 J/cm². The effects of the low-level laser therapy (LLLT) using an 810 nm diode laser on growth factor expression (EGF, TGF and VEGF) were evaluated by qPCR at 72 hours and 7 days after irradiation. Cell proliferation was evaluated at 24, 48 and 72 hours after LLLT using MTT assay. Results: Energy density of 12 J/cm² provoked irradiated gingival fibroblasts to demonstrate significantly higher proliferation as well as higher gene expression of Col1, VEGF and EGF. LLLT positive effects were obvious up to 7 days post-irradiation. Conclusion: LLLT with 810 nm presents beneficial effects on proliferation, collagen production and growth factor expression in human gingival fibroblast cells. The application of 12 J/cm² can be suggested as the optimal energy density for the enhancement of the wound healing process.

Mechanical Enhancement of Cytocompatible 3D Scaffolds, Consisting of Hydroxyapatite Nanocrystals and Natural Biomolecules, Through Physical Cross-Linking

Bioinspired scaffolds mimicking natural bone-tissue properties holds great promise in tissue engineering applications towards bone regeneration. Within this work, a way to reinforce mechanical behavior of bioinspired bone scaffolds was examined by applying a physical crosslinking method. Scaffolds consisted of hydroxyapatite nanocrystals, biomimetically synthesized in the presence of collagen and l-arginine. Scaffolds were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), microcomputed tomography, and nanoindentation. Results revealed scaffolds with bone-like nanostructure and composition, thus an inherent enhanced cytocompatibility. Evaluation of porosity proved the development of interconnected porous network with bimodal pore size distribution. Mechanical reinforcement was achieved through physical crosslinking with riboflavin irradiation, and nanoindentation tests indicated that within the experimental conditions of 45% humidity and 37 °C, photo-crosslinking led to an increase in the scaffold’s mechanical properties. Elastic modulus and hardness were augmented, and specifically elastic modulus values were doubled, approaching equivalent values of trabecular bone. Cytocompatibility of the scaffolds was assessed using MG63 human osteosarcoma cells. Cell viability was evaluated by double staining and MTT assay, while attachment and morphology were investigated by SEM. The results suggested that scaffolds provided a cell friendly environment with high levels of viability, thus supporting cell attachment, spreading and proliferation.

Determinants of corrosion resistance of Ti-6Al-4V alloy dental implants in an In Vitro model of peri-implant inflammation

Background

Titanium (Ti) and its alloys possess high biocompatibility and corrosion resistance due to Ti ability to form a passive oxide film, i.e. TiO₂, immediately after contact with oxygen. This passive layer is considered stable during function in the oral cavity, however, emerging information associate inflammatory peri-implantitis to vast increases in Ti corrosion products around diseased implants as compared to healthy ones. Thus, it is imperative to identify which factors in the peri-implant micro-environment may reduce Ti corrosion resistance.

Methods

The aim of this work is to simulate peri-implant inflammatory conditions in vitro to determine which factors affect corrosion susceptibility of Ti-6Al-4V dental implants. The effects of hydrogen peroxide (surrogate for reactive oxygen species, ROS, found during inflammation), albumin (a protein typical of physiological fluids), deaeration (to simulate reduced pO₂ conditions during inflammation), in an acidic environment (pH 3), which is typical of inflammation condition, were investigated. Corrosion resistance of Ti-6Al-4V clinically-relevant acid etched surfaces was investigated by electrochemical techniques: Open Circuit Potential; Electrochemical Impedance Spectroscopy; and Anodic Polarization.

Results

Electrochemical tests confirmed that most aggressive conditions to the Ti-6Al-4V alloy were those typical of occluded cells, i.e. oxidizing conditions (H₂O₂), in the presence of protein and deaeration of the physiological medium.

Conclusions

Our results provide evidence that titanium’s corrosion resistance can be reduced by intense inflammatory conditions. This observation indicates that the micro-environment to which the implant is exposed during peri-implant inflammation is highly aggressive and may lead to TiO₂ passive layer attack. Further investigation of the effect of these aggressive conditions on titanium dissolution is warranted.

A randomized controlled clinical trial on the effectiveness of three different mouthrinses (chlorhexidine with or without alcohol and C31G), adjunct to periodontal surgery, in early wound healing

OBJECTIVES

The use of chlorhexidine (CHX) with or without alcohol has been recommended for a number of clinical applications. On the other hand, there is a plethora of widely subscribed antiseptics, such as agent C31G (alkyl dimethyl glycine/alkyl dimethyl amine oxide), which has not yet been evaluated postsurgically. The effectiveness of three different mouthrinses (CHX with and without alcohol, C31G) in plaque control and early wound healing was compared postoperatively.

MATERIALS AND METHODS

In this, randomized, double-blind, controlled clinical trial 42 patients were allocated to three groups assigned to 2 weeks rinsing after non-regenerative periodontal flap surgery with or without osseous surgery with C31G (group A), alcohol-free CHX 0.12% (group B) or alcohol-based CHX 0.12% (group C). At days 7 and 14, plaque and early wound healing indices were recorded. At day 14, total bacterial counts were estimated utilizing real-time quantitative polymerase chain reaction (qPCR). Statistics included linear and generalized linear mixed models.

RESULTS

At day 7, healing response was not significantly different among groups. At day 14, group A revealed the highest while group C demonstrated the lowest plaque index values (B vs A, odds ratio-OR = 0.18, p = 0.012; C vs A, OR = 0.01, p < 0.001; C vs B, OR = 0.06, p < 0.001). Group C demonstrated the lowest bacterial counts levels at day 14 (38.470 × 10⁶, 48.190 × 10⁶, and 3.020 × 10⁶ for groups A, B, and C, respectively). At day 14, healing was significantly better in group C compared to B (p = 0.007). Group A showed no significant differences compared to other groups.

CONCLUSIONS

(1) The presence of alcohol may increase the effectiveness of CHX in early wound healing, (2) C31G might be an alternative solution prescribed during early postoperative period after non-regenerative periodontal flap surgery.

CLINICAL RELEVANCE

The present study found that active agent C31G displayed no significant differences to CHX formulations regarding periodontal wound healing improvement and might be used alternatively after non-regenerative periodontal flap surgery. In addition, an alcohol based 0.12% CHX mouthwash was more effective than an alcohol-free 0.12% CHX and C31G mouthrinse on plaque control in the absence of mechanical oral hygiene.

Osseointegration of Dental Implants in a Patient with Hajdu-cheney Syndrome

Background:

Hajdu-Cheney Syndrome (HCS) is a rare hereditary bone metabolism disorder characterized by acro-osteolysis, short stature, craniofacial changes, periodontitis and premature tooth loss. Extensive search of the current literature revealed no reports of implant placement in patients with HCS.

Case Report:

A 22-year old woman with osteoporosis, generalized advanced chronic periodontitis and premature tooth loss was referred to the Postgraduate Clinic of Periodontology, University of Athens-Greece. The patient was diagnosed in 2001 with HCS. The patient received non-surgical periodontal treatment and several teeth were extracted due to extensive alveolar bone loss.

After careful consideration of the possible implications deriving from the patient’s condition and having taken her young age into account, initially, a dental implant was placed in the upper right first premolar region. Specific protocols such as longer healing periods were implemented, so five years after placement and successful osseointegration of this implant, four additional dental implants were placed in the posterior regions of the maxilla and the mandible. Prosthetic rehabilitation followed 6 months after implant placement. Upon completion of periodontal treatment, the patient was enrolled in a periodontal maintenance program.

Results:

Clinical and radiographic examination of the patient during the periodontal maintenance program after implant placement revealed no abnormalities in the implant region.

Conclusion:

Patients with HCS suffer from periodontitis, bone destruction and premature tooth loss. This case indicates the successful osseointegration of dental implants in patients with HCS. However, further research is required in order to determine the predictability of dental implant placement in those patients.

Effect of rhTGF-β1 combined with bone grafts on human periodontal cell differentiation

Various techniques and materials have been proposed for the treatment of periodontal defects. In periodontal regeneration, periodontal ligament (PDL) cell differentiation as well as certain growth factors and their delivery system applied are critical. The purpose of this study was to evaluate the in vitro effect of recombinant human transforming growth factor-beta 1 (rhTGF-β1) combined with two different bone grafts on human PDL (hPDL) cell differentiation. The hPDL cells were treated with TGF-β1 alone or in combination with a calcified freeze-dried bone allograft (FDBA) and a porous biphasic calcium phosphate (BC) bone graft. Cell differentiation effect was estimated by measuring alkaline phosphatase (ALPase) activity and osteocalcin secretion. Results demonstrated that rhTGF-β1 alone or in combination with FDBA and BC provoked a significant (p<0.05) increase in ALPase activity as compared with controls. The findings of this study confirmed the beneficial role of rhTGF-β1 combined with FDBA and BC as carriers in periodontal regeneration.

A comprehensive and critical review of dental implant prognosis in periodontally compromised partially edentulous patients

OBJECTIVES

The outcome of implant treatment in periodontally compromised partially edentulous patients has not been completely clarified. Therefore, the aim of the present study was to perform, applying a systematic methodology, a comprehensive and critical review of the prospective studies published in English up to and including August 2006, regarding the short-term (<5 years) and long-term (>or=5 years) prognosis of osseointegrated implants placed in periodontally compromised partially edentulous patients.

MATERIAL AND METHODS

Using The National Library Of Medicine and Cochrane Oral Health Group databases, a literature search for articles published up to and including August 2006 was performed. At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently and in duplicate by the three reviewers (I. K. K., S. K., I. F.).

RESULTS

The search provided 2987 potentially relevant titles and abstracts. At the first phase of evaluation, 2956 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 31 publications was retrieved for more detailed evaluation. Finally, 15 prospective studies were selected, including seven short-term and eight long-term studies. Because of considerable discrepancies among these studies, meta-analysis was not performed.

CONCLUSIONS

No statistically significant differences in both short-term and long-term implant survival exist between patients with a history of chronic periodontitis and periodontally healthy individuals. Patients with a history of chronic periodontitis may exhibit significantly greater long-term probing pocket depth, peri-implant marginal bone loss and incidence of peri-implantitis compared with periodontally healthy subjects. Even though the short-term implant prognosis for patients treated for aggressive periodontitis is acceptable, on a long-term basis the matter is open to question. Alterations in clinical parameters around implants and teeth in aggressive periodontitis patients may not follow the same pattern, in contrast to what has been reported for chronic periodontitis patients. However, as only three studies comprising patients treated for aggressive periodontitis were selected, more studies, specially designed, are required to evaluate implant prognosis in this subtype of periodontitis. As the selected publications exhibited considerable discrepancies, more studies, uniformly designed, preferably longitudinal, prospective and controlled, would be important.

A comprehensive and critical review of dental implant placement in diabetic animals and patients

OBJECTIVES

A thorough and exhaustive analysis of the available studies concerning placement of endosseous dental implants in diabetic subjects has not been previously published. The aim of the present study was to perform a comprehensive and critical review of experimental and clinical studies published in the international peer-reviewed literature in the English language regarding endosseous implant installation in diabetic subjects and to draw evidence-based conclusions on the effectiveness and predictability of dental implant therapy in diabetic patients.

MATERIAL AND METHODS

Literature search for articles published up to and including March 2005 in the English language was performed with a personal computer (PC) using The National Library Of Medicine (http://www.ncbi.nlm.nih.gov/PubMed) and Cochrane Oral Health Group databases. Search strategy included a specific series of terms and key words. The reference lists of identified publications, relevant texts and previous workshops were also scanned. Data sources also included several hand-searched journals and contact with experts, when it was considered appropriate. Search was conducted independently by the three reviewers (S. K., I. K. K., I. F.). At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently by the three reviewers. Disagreement regarding inclusion of full papers was resolved by discussion among the reviewers.

RESULTS

The search provided 227 potentially relevant titles and abstracts. At the first phase of evaluation, 199 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 28 publications was retrieved for more detailed evaluation. These publications included 11 experimental studies and 16 clinical studies (one clinical study corresponded to two publications). Finally, 11 experimental and eight clinical studies were accepted. Clinical studies included four prospective and four retrospective studies. Because of the limited number of available studies and their heterogeneity, focusing on a specific predefined question to be answered by a systematic review was not feasible and therefore no meta-analysis was planned.

CONCLUSION

Within the limits of the existing investigations, experimental studies seem to reveal an impaired bone healing response to implant placement in diabetic animals compared with non-diabetic controls, both quantitatively and qualitatively. The majority of clinical studies tend to indicate that diabetes is no contraindication for implant placement, on condition that it remains under metabolic control. However, definitive guidelines with objective criteria, such as type and duration of diabetes and glucosylated hemoglobin levels, need to be established in the future.

Effect of implant design on survival and success rates of titanium oral implants: a 10-year prospective cohort study of the ITI Dental Implant System

AIM

The aim of this 10-year study (observation time 8-12 years, mean: 10 years) was to compare the survival rates, success rates and incidences of biological complications using three different implant designs of the ITI Dental Implant System.

MATERIAL AND METHODS

In 89 dental patients treated comprehensively, a total of 112 hollow screw (HS), 49 hollow cylinder (HC) and 18 angulated hollow cylinder (AHC) implants were installed depending on the available bone volume and according to prosthetic needs. One and 10 years after surgical placement, clinical and radiographic parameters were assessed. The incidences of peri-implantitis according to various thresholds were registered over 10 years of maintenance.

RESULTS

Success criteria at 10 years were set at: pocket probing depth (PPD)< or =5 mm, bleeding on probing (BoP)-, bone loss < 0.2 mm annually. The survival rate for HS was 95.4%, for HC 85.7% and for AHC 91.7%. Ninety percent of all the HS, 71% of the HC and 88% of the AHC did not present with an incidence of peri-implantitis over the 10 years, HC having significantly higher incidence of peri-implantitis than HS (P< 0.004). With the success criteria set above, a success rate for HS of 74%, for HC of 63% and for AHC of 61% was identified at 10 years. However, including a definition of PPD< or =6 mm, BoP - and bone loss < 0.2 mm annually for success, the rates for HS were 78%, for HC 65% and for AHC 67%, respectively. Basing success criteria purely on clinical parameters (without radiographic analysis), such as: PPD< or =5 mm and BoP-, the success rates increased to 90%, 76% and 89%, respectively. With PPD< or =6 mm and BoP - as success criteria chosen, the respective rates were 94%, 82% and 94% for HS, HC and AHC implants, respectively.

CONCLUSIONS

A significantly higher survival rate as well as a significantly lower incidence of peri-implantitis was identified for hollow screw design ITI Dental Implants after 10 years of service when compared to hollow cylinder design ITI Dental Implants (95.4% vs. 85.7%; 10% vs. 29%). Depending on the setting of the threshold criteria for success, success rates are highly variable and hence, reporting of success rates with elaboration on the criteria set appears crucial for comparison of different studies.

Association between periodontal and peri-implant conditions: a 10-year prospective study

OBJECTIVES

The aims of this study were to (1) compare prospectively the clinical and radiographic changes in periodontal and peri-implant conditions, (2) investigate the association of changes in periodontal parameters and peri-implant conditions over a mean observation period of 10 years (8-12 years) after implant installation, and (3) evaluate patient risk factors known to aggravate the periodontal conditions for their potential influence on the peri-implant tissue status.

MATERIALS AND METHODS

Eighty-nine partially edentulous patients with a mean age of 58.9 years (28-88 years) were examined at 1 and 10 years after implant placement. The patients contributed with 179 implants that were placed after comprehensive periodontal treatment and restored with crowns or fixed partial dentures. One hundred and seventy-nine matching control teeth were chosen as controls. Also, the remaining teeth (n=1770) in the dentitions were evaluated. Data on smoking habits and general health aspects were collected at 1 and 10 years as well.

RESULTS

At 10 years, statistically significant differences existed between implants and matching control teeth with regard to most of the clinical and radiographic parameters (P<0.01) with the exception of plaque index (PII) and recession. Multiple regression analyses were performed to associate combinations of periodontal diagnostic parameters to the peri-implant conditions: probing attachment level (PAL) at implants at 10 years was associated with implant location, full-mouth probing pocket depth (PPD) and full-mouth PAL (P=0.0001, r2=0.36). PPD at implants at 10 years correlated to implant location, full-mouth PPD and full-mouth PAL (P<0.001, r2=0.47). Marginal bone level at implants at 10 years was significantly associated to smoking, general health condition, implant location, full-mouth PAL and change over time in full-mouth PPD (P<0.001, r2=0.39).

CONCLUSIONS

These results present evidence for the association between periodontal and peri-implant conditions and the changes in these tissues over 10 years in partially edentulous patients.

Effect of GBR in combination with deproteinized bovine bone mineral and/or enamel matrix proteins on the healing of critical-size defects

OBJECTIVES

To evaluate the effect of guided bone regeneration (GBR) in combination with or without deproteinized bovine bone mineral (DBBM) and/or an enamel matrix derivative (EMD) on the healing of critical-size calvarial defects.

MATERIAL AND METHODS

Forty rats were used. In all animals, a standardized critical-size calvarial defect was created surgically. The animals were randomly allocated into 4 groups of 10 animals each. Group A: One calvarial defect was left untreated, while the galeal and the cerebral aspect of the contralateral defect were covered with a bioresorbable membrane (GBR). Group B: One calvarial defect was filled with EMD, while the contralateral defect was treated with GBR and EMD. Group C: One defect was filled with DBBM, while the contralateral defect was treated with combination of GBR and DBBM. Group D: One defect was filled with DBBM combined with EMD, while the contralateral defect was treated with combination of GBR, DBBM and EMD. The healing period was 4 months. Five specimens from each group were macerated and the length, the width and the vertical dimension (thickness) of the remaining defect were evaluated by a stereomicroscope. The remaining specimens in each group were analyzed histologically.

RESULTS

The defects of the macerated specimens that were left untreated or were treated only by EMD, DBBM and combination of EMD and DBBM did not present predictably complete healing of the defects. All the defects where GBR was applied alone or combined with DBBM and/or EMD presented always complete healing (P<0.05). The combined use of GBR with EMD and/or DBBM did not offer any significant advantage above GBR alone in terms of healing of the length and the width of the defect. However, the vertical dimension of the defect was significantly higher (P<0.05) in the GBR-treated specimens of Groups C and D. The histological analysis supported these findings.

CONCLUSION

The predictability of bone formation in critical-size defects depends mainly on the presence or absence of barrier membranes (GBR). The combined use with deproteinized bovine bone mineral and/or enamel matrix proteins did not significantly enhance the potential for complete healing provided by the GBR procedure.

Effect of GBR in combination with deproteinized bovine bone mineral and/or enamel matrix proteins on the healing of critical-size defects

OBJECTIVES

To evaluate the effect of guided bone regeneration (GBR) in combination with or without deproteinized bovine bone mineral (DBBM) and/or an enamel matrix derivative (EMD) on the healing of critical-size calvarial defects.

MATERIAL AND METHODS

Forty rats were used. In all animals, a standardized critical-size calvarial defect was created surgically. The animals were randomly allocated into 4 groups of 10 animals each. Group A: One calvarial defect was left untreated, while the galeal and the cerebral aspect of the contralateral defect were covered with a bioresorbable membrane (GBR). Group B: One calvarial defect was filled with EMD, while the contralateral defect was treated with GBR and EMD. Group C: One defect was filled with DBBM, while the contralateral defect was treated with combination of GBR and DBBM. Group D: One defect was filled with DBBM combined with EMD, while the contralateral defect was treated with combination of GBR, DBBM and EMD. The healing period was 4 months. Five specimens from each group were macerated and the length, the width and the vertical dimension (thickness) of the remaining defect were evaluated by a stereomicroscope. The remaining specimens in each group were analyzed histologically.

RESULTS

The defects of the macerated specimens that were left untreated or were treated only by EMD, DBBM and combination of EMD and DBBM did not present predictably complete healing of the defects. All the defects where GBR was applied alone or combined with DBBM and/or EMD presented always complete healing (P<0.05). The combined use of GBR with EMD and/or DBBM did not offer any significant advantage above GBR alone in terms of healing of the length and the width of the defect. However, the vertical dimension of the defect was significantly higher (P<0.05) in the GBR-treated specimens of Groups C and D. The histological analysis supported these findings.

CONCLUSION

The predictability of bone formation in critical-size defects depends mainly on the presence or absence of barrier membranes (GBR). The combined use with deproteinized bovine bone mineral and/or enamel matrix proteins did not significantly enhance the potential for complete healing provided by the GBR procedure.

Simultaneous or staged installation with guided bone augmentation of transmucosal titanium implants

A prospective cohort study of 45 nonsmoking consecutively admitted patients was studied for the treatment outcomes following jaw bone augmentation in conjunction with installment of oral implants. Twenty-eight patients were treated for both bone augmentation and implant treatment simultaneously, while 17 patients were treated with a staged approach with the bone augmentation being performed 6-8 months prior to implant installation. Three months following this, prosthetic reconstructions were incorporated. One year thereafter, baseline data and 3 years after reconstruction, follow-up data were obtained. Moderately low mean scores for the bleeding on probing percentage were found at baseline (24%) and after 3 years of function (17%), while the corresponding values at the implant sites were 40.6% and 52.4%, respectively. However, the modified gingival index (mGI) = 2 was found in only 4.8%, and 6.9% at the baseline and 3-year examinations. Peri-implant Probing depth (PPD) and level of attachment mean values did not vary between baseline and follow-up examinations. Only a small proportion of 1.8% yielded PPD = 6.0 mm after 3 years of function. Radiographic bone level measurements showed that 18.2% of the implants lost 0.5 mm during the observation period. Seventy percent of the sites were considered completely stable. It was concluded that predictable treatment outcomes resulted for oral implant installation combined with or staged after jawbone augmentation. Only 6.5% of the sites had lost 1.5% crestal bone with the staged approach while 14% of the sites had lost 1.5 mm, when the implants were placed simultaneously. This suggests that the staged approach may have a lower risk for greater amounts of crestal bone loss as the simultaneous approach. In general, crestal bone loss encountered in the present study corresponded very well with that reported following placement of the same implant system into nonaugmented bone.

Long-term implant prognosis in patients with and without a history of chronic periodontitis: a 10-year prospective cohort study of the ITI Dental Implant System

AIM

The aim of this 10-year study was to compare the failure, success and complication rates between patients having lost their teeth due to periodontitis or other reasons.

MATERIAL AND METHODS

Fifty-three patients who received 112 hollow screw implants (HS) of the ITI Dental Implant System were divided into two groups: group A - eight patients with 21 implants having lost their teeth due to chronic periodontitis; group B - forty five patients with 91 implants without a history of periodontitis. One and 10 years after surgical placement, clinical and radiographic parameters were assessed. The incidences of peri-implantitis were noticed over the 10 years of regular supportive periodontal therapy.

RESULTS

Success criteria at 10 years were set at: pocket probing depth (PPD) <or=5 mm, bleeding on probing (BoP-, bone loss <0.2 mm annually. The survival rate for the group with a past history of chronic periodontitis (group A) was 90.5%, while for the group with no past history of periodontitis (group B) it was 96.5%. Group A had a significantly higher incidence of peri-implantitis than group B (28.6% vs. 5.8%). With the success criteria set, 52.4% in group A and 79.1% of the implants in group B were successful. With a threshold set at PPD <or=6 mm, BoP- and bone loss <0.2 mm annually, the success rates were elevated to 62% and 81.3% for groups A and B, respectively. Relying purely on clinical parameters of PPD <or=5 mm and BoP-, the success rates were at 71.4% and 94.5%, and with a threshold set at PPD <or=6 mm and BoP-, these proportions were elevated to 81% and 96.7% for groups A and B, respectively.

CONCLUSIONS

Patients with implants replacing teeth lost due to chronic periodontitis demonstrated lower survival rates and more biological complications than patients with implants replacing teeth lost due to reasons other than periodontitis during a 10-year maintenance period. Furthermore, setting of thresholds for success criteria is crucial to the reporting of success rates.