The Socket Shield Technique: Stability of the Buccal Peri-implant Bone after Partial Root Removal - A Prospective Case Series of 20 patients, with 18 Months Follow-up.

OBJECTIVE: This study aims to collect data on implant survival, bone volume maintenance, and complications associated with the socket shield technique. BACKGROUND DATA: The socket shield technique was introduced in 2010. Since then, several systematic reviews have been published, showing good clinical outcomes. The behaviour of the buccal bone plate is so far not completely understood. METHODS: The study involved the placement of 23 implants using the socket shield technique in 20 patients. AstraTech EV implants were used, and no bone substitutes or connective tissue grafts were applied. Patients were monitored for 18 months, recording implant survival, volumetric bone analysis on CBCT scans, interproximal bone levels, bone sounding, pink esthetic scores, and complications. Prosthetic procedures were also described, including temporary and final restorations. RESULTS: A 95.7% cumulative 18-month implant survival rate was obtained using the socket shield technique, with a significant but limited reduction in buccal bone thickness (BBT) after implant placement. One implant did not integrate and two shields were partially exposed. The mean pink esthetic score, 1 year after loading was 12.93 ± 1.22. CONCLUSION: The study suggests that the socket shield technique can result in limited reduction of the buccal bone volume, with a high implant survival rate. Re-entry studies are recommended to investigate the causes of bone resorption.

Do autologous platelet concentrates (APCs) have a role in intra-oral bone regeneration? A critical review of clinical guidelines on decision-making process.

In the past decades, personalized regenerative medicine has gained increased attention. Autologous platelet concentrates (APCs) such as PRP, PRGF, and L-PRF, all serving as a source of a large variety of cells and growth factors that participate in hard and soft tissue healing and regeneration, could play a significant role in regenerative periodontal procedures. This narrative review evaluated the relative impact of APCs in alveolar ridge preservation, sinus floor augmentation, and the regeneration of bony craters around teeth, both as a single substitute or in combination with a xenograft. L-PRF has a significant beneficial effect on alveolar ridge preservation (bone quality). The data for PRGF are less convincing, and PRP is controversial. L-PRF can successfully be used as a single substitute during transcrestal (≥3.5 mm bone gain) as well as 1-stage lateral window sinus floor elevation (>5 mm bone gain). For PRGF and especially PRP the data are very scarce. In the treatment of bony craters around teeth, during open flap debridement, L-PRF as a single substitute showed significant adjunctive benefits (e.g., >PPD reduction, >CAL gain, >crater depth reduction). The data for PRP and PRGF were non-conclusive. Adding PRP or L-PRF to a xenograft during OFD resulted in additional improvements (>PPD reduction, >CAL gain, >bone fill), for PRGF no data were found. Autologous platelet concentrates demonstrated to enhance bone and soft tissue healing in periodontal regenerative procedures. The data for L-PRF were most convincing. L-PRF also has the advantage of a greater simplicity of production, and its 100% autologous character.

Pre-operative, chair-side Zn-containing surgical stents affect morbidity and wound healing after free gingival graft harvesting: a randomized clinical trial.

OBJECTIVE: To compare a pre-operatively, chair-side made, zinc-containing surgical stent (ZN) and suturing of a gelatin-based hemostatic agent (HA) on palatal wound healing and patient morbidity after free gingival graft surgery (FGG). MATERIALS AND METHODS: Sixty patients requiring FGG were randomly divided into two groups to receive either a ZN or a sterile HA sutured on the surgical area. Patients were evaluated at 1st, 3rd, 7th, 14th, 28th, and 56th days following surgery. Overall surgical time, donor site surgical time, postoperative pain (PP), delayed bleeding (DB), changes in dietary habits (DH), burning sensation (BS), completion of re-epithelialization (CE), and patients' discomfort (PD) were evaluated. RESULTS: Donor site surgical time, PP, DB, DH, BS were statistically significantly lower in the ZN group together with faster completion of re-epithelialization compared to the HA group. CONCLUSION: Pre-operatively, chair-side made, zinc-containing surgical stents provided significant benefits for wound healing parameters and patients' postoperative morbidity after FGG harvesting. CLINICAL RELEVANCE: The results show that using Zn-containing palatal stent after free gingival graft surgery significantly reduces pain and patient morbidity during the postoperative period.

Adjunctive locally and systemically delivered antimicrobials during surgical treatment of peri-implantitis: A systematic review.

AIM: To answer the following PICOS question: "In patients with peri-implantitis, what is the efficacy of surgical therapy with adjunctive systemic or local antimicrobials, in comparison with surgical therapy alone, in terms of pocket probing depth reduction, as assessed in randomized controlled trials (RCTs) with at least 6 months of follow-up?" MATERIALS AND METHODS: A systematic literature search was conducted. Reduction in mean probing pocket depth (PPD) was the primary outcome. Secondary clinical outcomes were changes in suppuration (%), changes in bleeding on probing (BOP) (%), marginal bone level changes (mm), disease resolution (%), and implant/prosthesis loss (%). Patient-reported outcome measures, possible adverse effects, and oral-health-related quality of life were also extracted if such data were available. RESULTS: Four RCTs assessing the use of locally (two RCTs) and systemically (two RCTs) administered antimicrobial adjuncts to surgical treatment of peri-implantitis, with 6-36-month follow-up, were included. Because of the substantial heterogeneity of interventions between the studies, meta-analysis could not be performed. A reduction in the mean PPD was observed following all the involved surgical treatments, irrespective of the addition of antimicrobials. Except for the effect of systemic antimicrobials on marginal bone level changes and local antimicrobials on BOP, the effect of systemic and local antimicrobials was equivocal for all secondary outcome measures. CONCLUSIONS: Based on the limited available evidence, the adjunctive use of the currently tested systemic or local antimicrobials during surgical therapy, in comparison with surgical therapy alone, in patients with peri-implantitis does not seem to improve the clinical efficacy. With regard the use of systemic antimicrobials, only 50% of the cases showed disease resolution after 1 year. There is a lack of studies that consider the sole use of local antimicrobials. Therefore, their true effect remains unclear.

Individual "alveolar phenotype" limits dimensions of lateral bone augmentation.

AIM: Alveolar ridge resorption following tooth extraction often renders a lateral bone augmentation inevitable. Some patients, however, suffer from severe early (during graft healing, Eres ) and/or late (during follow-up, Lres ) graft resorption. We explored the hypothesis that the "individual phenotypic dimensions" may partially explain the degree of such resorptions. MATERIALS AND METHODS: Patients who underwent a guided bone regeneration (GBR) procedure were screened for inclusion according to the following criteria: (1) a relatively symmetrical maxillary arch; (2) an intact contra-lateral alveolar bone dimension; (3) the availability of a pre-operative cone-beam CT (CBCT); (4) a CBCT taken immediately after GBR, and (5) at least one CBCT scan ≥6 months after surgery. CBCT scans from different timepoints were registered and imported into the Mimics software (Materialise, Leuven, Belgium). Bone dimensions of the contra-lateral site of the augmentation, representing the "individual phenotypical dimension (IPD) of the alveolar crest", were superimposed on the augmented site and registered accordingly. As such, Eres and Lres could be measured over time, in relation to the IPD (in two dimensions; per millimetre apically from the alveolar crest, in the centre of the GBR), as well as in three dimensions (the entire GBR, 2 mm away from the mesial, distal, and apical border for standardization). RESULTS: A total of 17 patients (23 augmented sites) were included. After Eres , the outline of the augmentation was in general located ±1 mm outside the IPD, but ≥1.5 years after GBR, it further moved towards the IPD (85% within 0.5 mm distance). CONCLUSIONS: Within the limitations of this study, the results indicate that the dimensions of a lateral bone augmentation are defined by the "individual phenotypic bone boundaries" of the patient.

The accuracy of probing, ultrasound and cone-beam CT scans for determining the buccal bone plate dimensions around oral implants - A systematic review.

OBJECTIVE: The objective of this review was to assess the accuracy of available means of determining the BBT (buccal bone thickness) and/or BBL (buccal bone level). This was translated into the following research question: What is the accuracy of the available means of visualizing the BBP (buccal bone plate) to establish the BBT and/or the BBL, when compared to control measurements? As control measurements histomorphometric measurements, direct measurements and cone-beam computed tomography (CBCT) measurements in the absence of metal are accepted. BACKGROUND DATA: METHODS: The literary search was performed by searching the databases of MEDLINE, Embase, and Web of Science, up to July 13, 2021. Types of studies included were clinical, in vitro and animal trials, specifically looking into the bone level and/or bone thickness of the buccal bone plate at oral implants. Reference lists were hand searched for relevant articles. Two reviewers performed the data extraction and analysis. Only studies using reliable control measurements to evaluate the accuracy of the tested means of visualizing BBT and/or BBL were included for analysis. The QUADAS-2 tool was used to perform bias analysis on the relevant studies. Extracted data was tabulated to show the differences between test and control measurements for BBT and BBL. For in vitro studies on CBCT measurements of BBT meta-analysis could be performed. RESULTS: A total of 1176 papers were identified in the search. Twenty-two articles were used for data extraction and qualitative analysis. Of these studies nine were animal studies, 9 were in vitro studies and four were human studies. Six animal studies and three human studies provided data on probing. CBCT and sonography as techniques for visualizing the buccal bone plate. Probing at implant sites seems to provide data that correlates with a consistent distance from the BBP. Meta-analysis for probing studies could not be performed due to heterogeneity in the setups of these studies. Eleven studies on CBCT were eligible for inclusion. Of these three were animal studies, the remaining 8 studies were all in vitro studies. Meta-analysis was performed on the accuracy of CBCT for in vitro studies, finding a significant underestimation of the BBT when compared to control measurements by a mean difference of -0.15 mm with 95%CI [-0.26,-0.03]. Three studies were identified on measurement of BBT and/or BBL by sonography. This included one human study and two in vitro studies. The identified studies show a low error when determining the buccal bone level or thickness using sonography. All included studies possess a high risk of bias according to risk of bias analysis, mostly due to selection of the patient. CONCLUSION: A strong limitation of this systematic review is the inclusion of different studies with heterogeneous designs. Within the limits of this analysis it cannot be concluded that probing is an accurate way of visualizing the BBP. CBCT cannot yet be recommended as a standard diagnostic tool for follow-up of the BBP at oral implants. The application of sonography as a diagnostic tool to visualize the BBP needs further scientific validation.

The Evaluation of Different Osteotomy Drilling Speed Protocols on Cortical Bone Temperature, Implant Stability and Bone Healing: An Experimental Study in an Animal Model.

The aim of this study was to measure the effect of drilling speed on heat generation in the cortical bone, on primary and secondary implant stability of implants and on early and late bone healing with micro-computerized tomography (micro-CT). Sixty implants were placed in the iliac crest of 6 sheep in order to form 5 different drilling protocols: 50 rpm without saline cooling, and 400, 800, 1200, and 2000 rpm with saline cooling. Simultaneous cortical bone temperature and primary stability at the time of placement; secondary stability and the ratio between relative bone and tissue volume (BV/TV) in 2D and 3D in micro-CT analysis were evaluated after 4 and 8 weeks. The 50-rpm group had the highest cortical bone temperature and the longest operation duration with the highest primary stability. Slightly higher values of secondary stability (T2) and subsequent 2D and 3D BV/TV values were found in 1200 rpm with irrigation at 8 weeks. All groups had sufficient ISQ values at 8 weeks for loading although the micro-CT analysis showed varying percentages of bone tissue around implants. The influence of drill speed for implant osteotomy and its irrigation is minimal when it comes to changes in temperature of the cortical bone, primary and secondary implant stability, and BV/TV.

Effect of different platelet-rich fibrin matrices for ridge preservation in multiple tooth extractions: A split-mouth randomized controlled clinical trial.

AIM: To evaluate dimensional changes in the alveolar ridge and bone structure after tooth extraction when L-PRF or A-PRF+ was used in comparison to unassisted socket healing. MATERIALS AND METHODS: Twenty patients in need of at least three tooth extractions in the aesthetic zone were included. L-PRF, A-PRF+ or control was randomly assigned, leaving one empty socket/edentulous site between conditions. CBCT scans were obtained immediately after tooth extraction and after 3 months of healing. Horizontal and vertical dimensional changes of the ridge and socket fill were calculated. Histological and micro-CT analysis of bone biopsies were used to evaluate post-surgical bone structural healing. RESULTS: Mean horizontal and vertical changes at 1-mm below the crest (buccal and palatal side) were similar for the three sites (p > 0.05). For the socket fill, L-PRF (85.2%) and A-PRF+ (83.8%) showed superior values than the control (67.9%). The histological and radiological analysis reported more newly formed bone for the PRF groups, without any significant differences between both. CONCLUSIONS: PRF matrices failed to reduce the dimensional changes after multiple tooth extractions in the premaxilla. After 3-month healing, both PRF matrices showed radiographically a significant superiority for the socket fill. Histologically, they seemed to accelerate new bone formation.

The Effects of Photobiomodulation on Leukocyte and Platelet-Rich Fibrin as Barrier Membrane on Bone Regeneration: An Experimental Animal Study.

Objective: To compare the effects of leukocyte and platelet-rich fibrin (L-PRF) and photobiomodulation therapy (PBMT)-applied L-PRF (PBMT/L-PRF) as barrier membranes on new bone formation (BV/TV) for the treatment of critical-sized bone defects. Materials and methods: The right iliac crests of five sheep were used in this experimental animal study. Eight critical-sized defects were surgically created in each sheep and a total of 40 defects were obtained. A deproteinized bovine bone graft was placed in all defects, and the defects were divided into four groups to be covered with L-PRF membrane, PBMT/L-PRF membrane, collagen membrane, or left uncovered as controls. Animals were sacrificed at 1 month. The sections obtained were histomorphometrically analyzed. Results: The results showed that the collagen group presented significantly higher values for main bone healing parameters (BV/TV, bone volume, and bone surface; p < 0.05). The PBMT/L-PRF group presented higher values than the L-PRF group and controls for these parameters though not statistically significant (p > 0.05). Conclusions: The findings show that PBMT may provide additional regenerative properties to L-PRF when used as barrier membranes. However, these results did not reach the collagen membranes, which warrants further studies for adapting the laser parameters to increase regenerative capacity of L-PRF.

Bovine-derived xenograft in combination with autogenous bone chips versus xenograft alone for the augmentation of bony dehiscences around oral implants: A randomized, controlled, split-mouth clinical trial.

AIM: The aim of the study was to evaluate whether the use of a xenograft is not inferior to the use of xenograft and autogenous bone chips in treating dehiscences at implant placement. MATERIALS AND METHODS: After implant placement, leaving a dehiscence, control sites were treated using a composite graft (autogenous bone chips and xenograft) and at the test sites 100% xenograft was used. Both sites were covered with a resorbable collagen membrane. Dehiscences were measured clinically at implant placement and at re-entry. CBCT was taken immediately after implant placement and after 4 months. RESULTS: In total, 28 GBR procedures were performed in 14 patients. On average, the change in vertical defect height was 2.07 mm (46.7%-test group) and 2.28 mm (50.9%-control group) (p > .05). The horizontal defect width at the implant shoulder change on average 1.85 mm (40.5%-test group) and 1.75 mm (40.9%-control group) (p > .05). On average, a loss in augmentation thickness of 0.45 mm (68.9%-test group) and 0.64 mm (55.5% control group) between implant placement and augmentation and abutment surgery was obtained at the implant shoulder. CONCLUSION: Both treatment modalities seem to work to a certain extent. At implant shoulder level, the augmentation thickness seems to be disappeared after the healing phase. (NCT03946020).

Characterization of the Leukocyte- and Platelet-Rich Fibrin Block: Release of Growth Factors, Cellular Content, and Structure.

PURPOSE: The leukocyte- and platelet-rich fibrin block (L-PRF block) is a composite graft that combines a xenograft that is acting as a scaffold with L-PRF membranes that serve as a bioactive nodule with osteoinductive capacity. This study evaluated the properties of the L-PRF block and its components in terms of release of growth factors, cellular content, and structure. MATERIALS AND METHODS: The concentration of transforming growth factor-ß1 (TGF-ß1), vascular endothelial growth factor (VEGF), platelet-derived growth factor-AB (PDGF-AB) and bone morphogenetic protein-1 (BMP-1) released by a L-PRF membrane (mb) and a L-PRF block were examined with ELISA for five time intervals (0 to 4 hours, 4 hours to 1 day, 1 to 3 days, 3 to 7 days, 7 to 14 days). Those levels in L-PRF exudate and liquid fibrinogen were also evaluated. The cellular content of the liquid fibrinogen, L-PRF membrane and exudate was calculated. The L-PRF block was also analyzed by means of a microCT scan and scanning electron microscopy (SEM). RESULTS: TGF-ß1 was the most released growth factor after 14 days, followed by PDGF-AB, VEGF, and BMP-1. All L-PRF blocks constantly released the four growth factors up to 14 days. L-PRF membrane and liquid fibrinogen presented high concentration of leukocytes and platelets. The microCT and SEM images revealed the bone substitute particles surrounded by platelets and leukocytes, embedded in a dens fibrin network. CONCLUSION: The L-PRF block consists of deproteinized bovine bone mineral particles surrounded by platelets and leukocytes, embedded in a fibrin network that releases growth factors up to 14 days.

Leucocyte- and platelet-rich fibrin block for bone augmentation procedure: A proof-of-concept study.

AIM: The objective of this proof-of-concept study was to investigate the effects of a new guided bone regeneration technique with a tissue engineering approach. MATERIALS AND METHODS: This single cohort observational study evaluated the outcome of the leucocyte- and platelet-rich fibrin (L-PRF) Block for horizontal bone augmentation in the maxilla. The L-PRF Block is prepared by mixing a particulated biomaterial with chopped L-PRF membranes at a 50:50 ratio and adding liquid fibrinogen to glue all together. Horizontal augmentation was assessed linearly and volumetrically immediately after surgery and 5-8 months later by matching consecutive cone beam computed tomography (CBCTs). RESULTS: Ten patients (mean age of 50.7 years [±17.2]) representing 15 sites with horizontal alveolar deficiencies were included. Superimposition of pre-operative and posthealing CBCT scans showed an average linear horizontal bone gain of 4.6 mm (±2.3), 5.3 mm (±1.2) and 4.4 mm (±2.3), measured at 2, 6 and 10 mm from the alveolar crest, respectively. The volumetric gain was 1.05 cm3 (±0.7) on average. The resorption rate after 5-8 months was 15.6% (±6.7) on average. CONCLUSIONS: L-PRF Block may be a suitable technique to augment deficient alveolar ridges.

Volumetric changes of grafted volumes and the Schneiderian membrane after transcrestal and lateral sinus floor elevation procedures: A clinical, pilot study.

AIM: To investigate the influence of various surgical techniques for sinus augmentation on the volumetric changes of graft, membrane and the post-operative discomfort. MATERIALS AND METHODS: Eighteen patients in need of bilateral sinus floor elevation (SFE) were assigned to lateral SFE, transcrestal SFE and intralift procedures. CBCT images taken at baseline, 1 week and 6 weeks were analysed for volumetric changes in graft and Schneiderian membrane. Questionnaires were used to analyse post-op discomfort. RESULTS: The overall average graft volume obtained after 1 week was 1.87 cm3 (range 0.12-4.72 cm3 ). Volumes decreased after 6 weeks to an overall mean volume of 1.33 cm3 (range 0.10-4.29 cm3 - average decrease of 27.6%). After 6 weeks, the amount of graft volume decreased in every treatment option, ranging from -23.13% for the tSFE, over -24.55% for the lSFE, to -33.71% for the IL. Although all treatment options correspond in an increase in Schneiderian membrane volume, no statistically significant correlation between this increase and loss of graft volume could be obtained for all treatments (p = 0.97). CONCLUSION: All SFE techniques provided sufficient graft volume for implant treatment. All techniques provoke a partially transient swelling of the Schneiderian membrane. All techniques resulted in a decrease in graft volume after 6 weeks; however, no significant differences were obtained between treatments. Furthermore, no statistical significant correlation between the post-operative swelling of the Schneiderian membrane and reduction in graft volume at 6 weeks could be obtained.

An open, prospective, non-randomized, controlled, multicentre study to evaluate the clinical outcome of implant treatment in women over 60 years of age with osteoporosis/osteopenia: 1-year results.

BACKGROUND: Osteoporosis has been called a potential risk factor for bone healing around implants. AIM: The aim of this multicentre study was to verify the clinical performance of fluoridated implants in the maxilla of subjects with diagnosed systemic primary osteoporosis/osteopenia. MATERIAL AND METHODS: Postmenopausal women in need of 2-8 splinted implants in maxilla underwent bone mineral density measurements in the hip and spine, using dual-energy X-ray absorptiometry scans. Based on their T-scores, they were divided into two study groups: Group O (osteoporosis/osteopenia group) subjects had a T-score ≤-2, Group C (control group) had a T-score of ≥-1, and subjects with a T-score <-1 but >-2 were excluded. Implants were placed with a two-stage procedure and loaded 4-8 weeks after abutment surgery. At 6 months and 1 year after functional loading, clinical parameters (including peri-apical radiographs) were assessed. RESULTS: One hundred and forty-eight implants were placed in 48 subjects (mean age: 67 years (range [59-83]). Sixty-three implants were placed in 20 osteoporosis subjects (Group O, mean age: 69 years; range [59-83]), and 85 were placed in control subjects (Group C, mean age: 65 years; range [60-74]). The cumulative survival rate, on an implant level, was 99.3% (Group O: 98.4%; Group C: 100.0%). The cumulative survival rate, on a subject level, was 97.9% (Group O: 94.7%; Group C: 100.0%). Marginal bone level (MBL) alterations from functional loading to the 1-year follow-up visit were measured on an implant level and a subject level. The overall MBL alteration on an implant level was -0.01 ± 0.51 mm (Group O: -0.11 ± 0.49 mm; Group C: 0.05 ± 0.52 mm). The overall MBL alteration on a subject level was -0.04 ± 0.27 mm (Group O: -0.17 ± 0.30 mm; Group C: 0.04 ± 0.23 mm). CONCLUSION: Within the limitations of this prospective, non-randomized, controlled, multicentre study, it can be concluded that oral implant therapy in patients suffering from osteoporosis/osteopenia is a reliable treatment option with comparable integration rates as in healthy patients. Long-term follow of the study groups is necessary to compare marginal bone alterations and treatment outcomes.

Regenerative potential of leucocyte- and platelet-rich fibrin. Part A: intra-bony defects, furcation defects and periodontal plastic surgery. A systematic review and meta-analysis.

AIM: To analyse the regenerative potential of leucocyte- and platelet-rich fibrin (L-PRF) during periodontal surgery. MATERIALS AND METHODS: An electronic and hand search were conducted in three databases. Only randomized clinical trials were selected and no follow-up limitation was applied. Pocket depth (PD), clinical attachment level (CAL), bone fill, keratinized tissue width (KTW), recession reduction and root coverage (%) were considered as outcome. When possible, meta-analysis was performed. RESULTS: Twenty-four articles fulfilled the inclusion and exclusion criteria. Three subgroups were created: intra-bony defects (IBDs), furcation defects and periodontal plastic surgery. Meta-analysis was performed in all the subgroups. Significant PD reduction (1.1 ± 0.5 mm, p < 0.001), CAL gain (1.2 ± 0.6 mm, p < 0.001) and bone fill (1.7 ± 0.7 mm, p < 0.001) were found when comparing L-PRF to open flap debridement (OFD) in IBDs. For furcation defects, significant PD reduction (1.9 ± 1.5 mm, p = 0.01), CAL gain (1.3 ± 0.4 mm, p < 0.001) and bone fill (1.5 ± 0.3 mm, p < 0.001) were reported when comparing L-PRF to OFD. When L-PRF was compared to a connective tissue graft, similar outcomes were recorded for PD reduction (0.2 ± 0.3 mm, p > 0.05), CAL gain (0.2 ± 0.5 mm, p > 0.05), KTW (0.3 ± 0.4 mm, p > 0.05) and recession reduction (0.2 ± 0.3 mm, p > 0.05). CONCLUSIONS: L-PRF enhances periodontal wound healing.

Regenerative potential of leucocyte- and platelet-rich fibrin. Part B: sinus floor elevation, alveolar ridge preservation and implant therapy. A systematic review.

AIM: To analyse the effect of leucocyte- and platelet-rich fibrin (L-PRF) on bone regeneration procedures and osseointegration. MATERIALS AND METHODS: An electronic and hand search was conducted in three databases (MEDLINE, EMBASE and Cochrane). Only randomized clinical trials, written in English where L-PRF was applied in bone regeneration and implant procedures, were selected. No follow-up restrictions were applied. RESULTS: A total of 14 articles were included and processed. Three subgroups were created depending on the application: sinus floor elevation (SFE), alveolar ridge preservation and implant therapy. In SFE, for a lateral window as well as for the trans-alveolar technique, histologically faster bone healing was reported when L-PRF was added to most common xenografts. L-PRF alone improved the preservation of the alveolar width, resulting in less buccal bone resorption compared to natural healing. In implant therapy, better implant stability over time and less marginal bone loss were observed when L-PRF was applied. Meta-analyses could not be performed due to the heterogeneity of the data. CONCLUSIONS: Despite the lack of strong evidence found in this systematic review, L-PRF might have a positive effect on bone regeneration and osseointegration.

The use of leucocyte and platelet-rich fibrin in socket management and ridge preservation: a split-mouth, randomized, controlled clinical trial.

AIM: To investigate the influence of the use L-PRF as a socket filling material and its ridge preservation properties. MATERIALS AND METHODS: Twenty-two patients in need of single bilateral and closely symmetrical tooth extractions in the maxilla or mandible were included in a split-mouth RCT. Treatments were randomly assigned (L-PRF socket filling versus natural healing). CBCT scans were obtained after tooth extraction and three months. Scans were evaluated by superimposition using the original DICOM data. Mean ridge width differences between timepoints were measured at three levels below the crest on both the buccal and lingual sides (crest -1 mm (primary outcome variable), -3 mm and -5 mm). RESULTS: Mean vertical height changes at the buccal were -1.5 mm (±1.3) for control sites and 0.5 mm (±2.3) for test sites (p < 0.005). At the buccal side, control sites values were, respectively, -2.1 (±2.5), -0.3 mm (±0.3) (p < 0.005) and -0.1 mm (±0.0), and test sites values were, respectively, -0.6 mm (±2.2) (p < 0.005), -0.1 mm (±0.3) and 0.0 mm (±0.1). Significant differences (p < 0.005) were found for total width reduction between test (-22.84%) and control sites (-51.92%) at 1 mm below crest level. Significant differences were found for socket fill (visible mineralized bone) between test (94.7%) and control sites (63.3%). CONCLUSION: The use of L-PRF as a socket filling material to achieve preservation of horizontal and vertical ridge dimension at three  months after tooth extraction is beneficial.

Influence of Skeletal and Local Bone Density on Dental Implant Stability in Patients with Osteoporosis.

BACKGROUND AND PURPOSE: Osteoporosis is a major skeletal disease affecting millions of people worldwide. Recent studies claim that patients with osteoporosis do not have a higher risk of early implant failure compared to non-osteoporotic patients. The aim of this study was to assess the effect of skeletal osteoporosis and local bone density on initial dental implant stability. MATERIALS AND METHODS: Seventy-three patients were recruited and were assigned (based on a Dual-energy X-ray Absorptiometry scan) to either the osteoporosis (Opr), osteopenia (Opn), or control (C) group. Forty nine of the 73 patients received dental implants and had implant stability measured by means of resonance frequency analysis (RFA) at implant placement and at prosthetic abutment placement. On the computerized tomography scans, the cortical thickness and the bone density (Hounsfield Units) at the sites of implant placement were measured. RESULTS: At implant placement, primary stability was on average lower in group Opr (63.3 ± 10.3 ISQ) than in group Opn (65.3 ± 7.5 implant stability qutient (ISQ)), and group C (66.7 ± 8.7 ISQ). At abutment placement, a similar trend was observed: group Opr (66.4 ± 9.5 ISQ) scored lower than group Opn (70.7 ± 7.8 ISQ), while the highest average was for group C (72.2 ± 7.2 ISQ). The difference between groups Opr and C was significant. Implant length and diameter did not have a significant effect on implant stability as measured with RFA. A significant correlation was found between local bone density and implant stability for all regions of interest. CONCLUSIONS: Implant stability seems to be influenced by both local and skeletal bone densities. The lower stability scores in patient with skeletal osteoporosis reinforce the recommendations that safe protocols and longer healing times could be recommended when treating those patients with dental implants.

The outcome of oral implants placed in bone with limited bucco-oral dimensions: a 3-year follow-up study.

AIM: The dimension of the alveolar bone reduces significantly after tooth loss. Clinicians consider a 1-2 mm buccal and lingual bone width mandatory around the implant at placement. This prospective study analysed the outcome of implants inserted in jaws with narrow (≤4.5 mm) buccal bone dimensions. MATERIAL AND METHODS: Twenty-eight patients (mean age 63, 89% female) with a narrow alveolar crest (≤4.5 mm in width on CBCT) received 100 implants (3.5 mm) via a two-stage procedure. Intra-oral radiographs were taken at placement, functional loading and after 1, 2 and 3-years of follow-up. Peri-implant bone level alterations were recorded by two calibrated, periodontologists. RESULTS: All implants integrated and the cumulative survival rate after 3 years was 100%. The implants were inserted 0.81 mm ± 0.83 subcrestal. At functional loading the bone was located 0.65 mm ± 0.6 apical of the implant shoulder. During 3 years of loading the amount of annual marginal bone loss was 0.17 ± 0.4, 0.05 ± 0.4 and - 0.06 ± 0.1 mm, respectively. CONCLUSION: Based on these data and within the limitations of this study it became clear that implants, placed in sites with limited dimensions (≤4.5 mm width), showed minimal amounts of marginal bone loss during the first 3 years of functional loading.

The accuracy of guided surgery via mucosa-supported stereolithographic surgical templates in the hands of surgeons with little experience.

OBJECTIVES: This prospective study analyzed the accuracy of implant placement with mucosa-supported stereolithographic guides, executed by inexperienced surgeons supervised by an experienced colleague. MATERIAL AND METHODS: For the accuracy analysis, 75 OsseoSpeed implants™, placed in 17 fully edentulous jaws (16 patients) using a mucosa-supported stereolithographic guide (IMPLANT SAFE Guide, DENTSPLY Implants) and the Facilitate™ protocol, were included. DICOM images of the pre-surgical planning and the post-surgical CBCT were matched using the Mimics(®) software (Materialise Dental). These data were compared with the data (12 jaws, 52 implants) of an experienced surgeon (Vercruyssen et al. Journal of Clinical Periodontology 2014; doi:10.1111/jcpe.12231). RESULTS: The global deviation at the coronal and apical point was 0.9 mm (SD 0.5) and 1.1 mm (SD 0.5), respectively. Depth deviations were 0.5 mm (SD 0.5) and 1.1 mm (SD 0.5), respectively, and the angular deviation was 2.8° (SD 1.5°). These deviations were statistically not inferior to the deviations of the experienced surgeon and also within the range of deviations reported by several systematic reviews. CONCLUSION: Within the limitations of this study and for the above-mentioned surgical protocol, inexperience of the surgeon had no influence on the accuracy of implant placement in fully edentulous jaws, when all steps needed for the procedure are supervised by experienced dentists.