Peri-implantitis induction and resolution around zirconia versus titanium implants.

BACKGROUND: This study compared titanium and zirconia implant ligature-induced peri-implant defect progression and response to regenerative surgical intervention. METHODS: Eight tissue-level endosseous implants were placed in 6 mixed-breed foxhounds, with 2 zirconia and 2 titanium alternating in each hemimandible. Cotton ligatures were placed subgingivally for 16 weeks followed by 8 weeks of spontaneous progression. Standardized radiographs were captured every 2 weeks to evaluate the rate of bone loss. Regenerative surgery was performed utilizing water-jet decontamination, enamel matrix derivative, and locally harvested autogenous bone. After 16 weeks of healing, final radiographic bone levels as well as probing depths, recession, and clinical attachment levels were assessed. RESULTS: All 48 implants integrated successfully. The final average post-ligature radiographic defects were 2.88 and 3.05 mm for titanium and zirconia implants, respectively. There was no significant difference between materials in the rate of radiographic bone loss (p = 0.09). Following regenerative surgery, the total average amount of radiographic bone gain was 1.41 and 1.20 mm for titanium and zirconia, respectively. The percentage of defect fill was 51.56% and 37.98% (p = 0.03) for titanium and zirconia, respectively. Inter-group differences were minimal for clinical parameters at the time of sacrifice including periodontal pocket depths (p = 0.81), recession (p = 0.98), or clinical attachment levels (p = 0.51). CONCLUSIONS: No significant difference was found in the rate of peri-implant defect development between titanium and zirconia implants. Both materials gained significant radiographic bone following regenerative surgery with significantly greater defect percentage fill in titanium implants. The final clinical parameters were similar in both groups.

Donor site wound healing following free gingival graft surgery using platelet rich fibrin: A randomized controlled trial.

BACKGROUND: The primary purpose of this two-arm, parallel design, randomized controlled study is to compare healing of the palatal tissue donor site when platelet-rich fibrin (PRF) is used as a wound dressing compared to the use of a hemostatic agent. Secondary outcomes of patient pain perception and analgesic intake were also evaluated. METHODS: Seventy-four patients receiving free gingival grafts were randomized to receive either PRF (test) or hemostatic agent (control) as a palatal wound dressing by patients selecting a sealed envelope containing their group assignment (initially 37 envelopes for PRF group and 37 for hemostatic agent group). Patient pain assessment and analgesic consumption were documented using a 21-point numerical scale (NMRS-21) at 24, 48, and 72 hours post-surgery. At 1-, 2-, 3-, and 4-week follow-up appointments palatal early healing index (PEHI) scores including wound color, epithelialization, presence or absence of swelling, granulation tissue, and bleeding on gentle palpation were generated by direct intraoral examination by a blinded examiner unaware of the patients' treatment group. RESULTS: NMRS-21 pain scores showed a significant reduction in pain over time in both groups, with no significant difference between groups at any time point. No significant between-group difference was found in the amount of analgesics taken by patients at 24, 48, and 72 hours. There was significant improvement in PEHI scores over the 4-week time period in both groups, but there was no significant difference in PEHI score at each time point (1, 2, 3, 4 weeks) between groups.  CONCLUSIONS: Study findings suggest that there is no difference in early palatal wound healing, patient pain perception, or analgesic consumption between use of PRF or a hemostatic agent as donor-site wound dressings.

Assessment of titanium release following non-surgical peri-implantitis treatment: A randomized clinical trial.

BACKGROUND: Peri-implantitis is a frequent finding. Initial treatment involves non-surgical debridement of the implant surface. Recent studies have found a correlation between titanium (Ti) particle release and peri-implantitis, yet there is a dearth of information regarding the effect of various non-surgical instrumentation on particle release or peri-implantitis resolution. METHODS: Patients with peri-implantitis were recruited for a randomized, blinded, parallel-group clinical trial. The implants were randomized to treatment composed of Ti curettes ("Mech" group) or implant-specific treatment composed of rotary polymer microbrushes ("Imp" group). Ti release in submucosal peri-implant plaque pre- and 8 weeks posttreatment was assessed as the primary outcome. Peri-implant probing depth, bleeding on probing, and suppuration on probing were evaluated and compared between groups. RESULTS: Thirty-four participants completed treatment; 18 were randomized to the Mech group and 16 to the Imp group. The groups were comparable for Ti levels and probing depths at baseline. A trend was noted for 10-fold greater Ti dissolution in the Mech group posttreatment compared to the Imp group (p = 0.069). The Imp group had a significant reduction in probing depth posttreatment (p = 0.006), while the Mech group reduction was not significant. CONCLUSION: Peri-implantitis treated non-surgically with implant-specific instruments (Imp group) had a significantly greater decrease in probing depth versus the Mech treatment group. This improvement was linked with a trend for less Ti release to the peri-implant plaque by the non-abrasive treatment.

A randomized controlled trial evaluating the effect of epithelial removal on free soft tissue autograft healing.

BACKGROUND: The purpose of this study is to determine if there is a difference in dimensional change of a free soft tissue autograft (FSTA) with epithelium compared to without epithelium. The secondary aim is to determine the patient and professional evaluation of color match and graft texture between the two groups. METHODS: Patients with ≤2 mm keratinized tissue indicated for a FSTA were randomly assigned to control group (FSTA with epithelium) or test group (de-epithelialized FSTA). The vertical and horizontal measurements of the grafts were taken at surgery, and 1, 3, and 6 months postoperatively. Patients were asked to evaluate the color match at each postoperative time point on a 21-step Numeric Rating Scale (NRS-21). Professional assessment of color match and graft texture were evaluated on images at the same time points. RESULTS: Forty-six patients and 55 grafts were included in the study. For change in graft height, width, and area, there were no significant differences between the treatment groups at any time point. Graft height and area in both groups decreased significantly from baseline to month 1 (p < .001), but no other difference was significant over time. When patients and professionals used the NRS-21 for evaluation of color match between the graft site and the surrounding soft tissue, there was no significant difference between the treatment groups. Similarly, evaluation of texture match on color images and black-and-white images revealed no significant differences between or within groups. CONCLUSION: De-epithelialized FSTA showed no difference in dimensional change or color and texture match compared to FSTA with epithelium.

Autologous blood products: Usage and preparation protocols.

FOCUSED CLINICAL QUESTION: What are the appropriate preparation protocols for autologous blood products to support their clinical utilization? SUMMARY: Autologous blood products provide a unique clinical benefit. Their popularity among the professions is growing. However, as this is a rapidly evolving field, multiple modalities are presented within the literature. Frequently there is no demonstrated superiority to previous iterations. This brief review attempts to offer a concise chronology on their evolution, preparation, and where possible, evidence to support their clinical utilization. CONCLUSIONS: The field of autologous blood products is expanding rapidly. These products appear to yield variable clinical benefits in specific indications. However, evidence supporting their universal application is scant, and the superiority of one formulation versus another is yet to be demonstrated.

Comparing the histological assessment following ridge preservation using a composite bovine-derived xenograft versus an alloplast hydroxyapatite-sugar cross-linked collagen matrix.

BACKGROUND: This randomized controlled trial was designed to evaluate the histological wound healing and alveolar ridge dimensional changes following ridge preservation using two different xenograft/collagen matrices. METHODS: Fifty-four patients each with non-molar teeth that required extraction and replacement with dental implants were enrolled. Teeth extractions were completed with minimal flap reflection and were randomized to receive ridge preservation with either 90% bovine-derived xenograft granules in a 10% porcine collagen matrix (Group A) or a sponge-like matrix of 80% microparticulate hydroxyapatite alloplast graft with 20% sugar cross-linked porcine type 1 collagen (Group B). After 16 weeks of healing and at the time of implant placement, a bone core biopsy was harvested followed by dental implant placement. The primary histological outcome evaluated were percentage of vital bone formation and connective tissue/other (fibrous tissue and marrow space). Secondary outcomes included the change in alveolar ridge width and the buccal and lingual ridge height. Statistical analysis was completed with two-sample t-test and Fisher exact test. RESULTS: Forty-four patients completed the study, 23 in group A and 21 in group B. Group B presented with statistically significantly (p = 0.02) more percentage of vital bone (39.3 ± 17.8) than group A (26.8 ± 15.8). No statistically significant difference was observed for changes in alveolar ridge dimensions. CONCLUSIONS: Group B, when used for ridge preservation, yields statistically significantly more vital bone over a 4-month healing period. Ridge dimension changes were similar between the two groups and were adequate for implant placement.

One-year implant survival following lateral window sinus augmentation using plasma rich in growth factors (PRGF): a retrospective study

BACKGROUND: The aim of this study was to assess one-year implant survival after lateral window sinus augmentation using PRGF combined with various bone grafting materials. MATERIAL AND METHODS: This was a retrospective chart review and radiographic analysis of patients that had under-gone lateral window sinus augmentation with PRGF and had dental implants placed at least 6 months post augmentation. All implants included were followed up for at least one year after placement. Demographic, sinus and implant related characteristics (residual ridge height, sinus membrane perforation, type of graft material, implant length and width and ISQ at placement) were analyzed. RESULTS: A total of 31 patients with 39 sinus augmentations and 48 implants were included. The mean follow up was 22.8 ± 9.9 months. Implant survival was 95.8%, with 2 implants overall failing. Among all the variables assessed, the only one found to be associated with an increased risk for implant failure was the use of xenograft as bone grafting material in the sinus. CONCLUSIONS: Within the limitations of this study, dental implants placed in maxillary sinuses grafted with PRGF in combination with bone grafting materials, exhibit high implant survival rates after at least one year follow up

No disponible

Dentist-Patient Communication of Treatment Outcomes in Periodontal Practice: A Need for Dental Patient-Reported Outcomes.

Periodontal practice has made tremendous progress toward evidence-based treatment over the past decade. Importantly, a new classification scheme for periodontal and peri-implant treatments has recently been devised that is incorporating current evidence and enabling patient-specific periodontal care. However, this important progress can be further accelerated with the availability of patient-perceived outcomes of periodontal and implant interventions. The majority of existing clinical studies assess treatment effects based on clinician-measured surrogate outcomes, such as probing depth and attachment levels which are easily communicated to or perceived by dental patients. As dental patient-reported outcomes (dPROs) gain momentum in dental practice, our understanding of the true outcome of dental therapies is vastly increasing. In periodontal research in particular, the utilization of dPROs has clearly demonstrated that periodontal disease contributes to an individual's burden of disease in a substantial manner. Correspondingly, disease treatment interventions seem to lead to varying levels of patient-perceived improvements. The present editorial aims to highlight the importance of patient communication of treatment outcomes in periodontal and implant research and to review the information on available measures for capturing dPROs.

Effect of different concentrations of commercially available mouthwashes on wound healing following periodontal surgery: a randomized controlled clinical trial.

OBJECTIVES: The purpose of this study was to evaluate the effect of chlorhexidine and essential oils containing mouth rinses on oral wound healing after periodontal flap surgery. MATERIALS AND METHODS: Eighty subjects participated in the study and were randomly assigned to use water, 0.12% chlorhexidine (CHX), essential oils (EO), 5% CHX, and 10% EO. Subjects were examined at 1, 2, and 3 weeks postoperatively. Plaque index (PI) and the modified gingival index (GI) were recorded, while wound epithelialization was measured to evaluate the healing process. Numerical data were analyzed with parametric test for multiple comparisons (ANOVA) with Bonferroni correction. Categorical data were analyzed using Chi-square test/fisher exact test. RESULTS: All groups demonstrated a gradual GI reduction from first to third visit. Patients in the CHX group presented statistically significant lower PI scores than patients in the water group at the all-time points of the study. Wound epithelialization analysis demonstrated that 100% of the sites in the CHX group were healing by secondary intention at visit 1. This finding was statistically significant. CONCLUSION: Full strength concentrations of CHX and EO did not show any detrimental effects on healing after traditional periodontal surgery at the end of the observation period. CLINICAL RELEVANCE: The use of chlorhexidine and EO containing mouthwashes does not appear to delay wound healing. Diluting these commercial mouthwashes may present an approach that could possibly reduce the adverse effects (such as tooth staining) associated with their use, while maintaining their antibacterial properties.

Retrospective study to identify associations between clinician training and dental implant outcome and to compare the use of MATLAB with SAS.

BACKGROUND: The aim of this study was to identify any associations between predictor variables, mainly clinician training and dental implant outcome, among the residents in different departments and to compare statistical analysis with the use of MATLAB R2017a™ to SAS version 9.4. METHODS: Dental records were reviewed from January 1, 2011, to December 31, 2015. Two thousand forty-eight dental implants were placed on 471 patients seen by residents from the departments of Periodontics, Prosthodontics, and Oral and Maxillofacial Surgery (OMFS) at Louisiana State University Health Sciences Center School of Dentistry. The following parameters were investigated by means of multilevel logistic regression analysis: demographics, implant parameters, department, and residents' year of training. RESULTS: A total of 1449 implants were included in the study. Overall, within a 1-5-year time period, 1343 (92.6%) implants had survived and 106 (7.4%) implants failed. Discipline (p = 0.0004), residents' year of training (p < 0.0001), and implant systems (p = 0.0024) showed significant associations with implant outcome. Periodontics had a survival rate of 94.14% followed by Prosthodontics (91.48%) and OMFS (89.64%). The survival rates of implants by year of training were as follows: third-year Periodontics and OMFS (94.20%), second-year (89.38%), and first-year (88.6%). CONCLUSION: The level and type of clinician training had an impact on implant outcome in different residency programs. Further studies will be necessary to identify the reasons for the differences in implant failure rates.

Plasma rich in growth factors (PRGF) in intraoral bone grafting procedures: A systematic review.

PURPOSE: This systematic review aimed at assessing the effects of PRGF in new bone formation, soft tissue healing and post-operative pain and swelling in sites that underwent ridge preservation, ridge augmentation and maxillary sinus augmentation procedures. MATERIALS AND METHODS: A comprehensive literature search employing seven databases was conducted by two independent reviewers. Only randomized and non-randomized controlled clinical trials using PRGF alone or in combination with bone grafting materials were selected. RESULTS: Overall, 919 studies were identified, of which a total of 8 articles were included in the qualitative analysis. Two of the selected studies reported on ridge preservation, one on ridge augmentation and five on maxillary sinus augmentation. Positive results were recorded for soft tissue healing and post-operative pain and swelling following these procedures. However, outcomes of PRGF on new bone formation post extraction and on maxillary sinus augmentation when combined with other biomaterials were conflicting. Meta-analysis could not be conducted for any variables due to the heterogeneity of selected studies. CONCLUSION: Limited evidence exists on the effects of PRGF in different intraoral bone grafting procedures, with some benefit reported on soft tissue healing and post-operative symptomatology. As this platelet concentrate is commonly used in clinical practice, further research is needed to fully assess its clinical indications and effectiveness.

Immediate and Early Loading of Hydrothermally Treated, Hydroxyapatite-Coated Dental Implants: 2-Year Results from a Prospective Clinical Study.

This investigation was undertaken to determine if multithreaded implants partially coated with plasma-sprayed hydroxyapatite (HA) could be effectively loaded earlier than 3-6 months after placement. Forty-eight patients (22 men, 26 women) were enrolled in the study and received 48 implants. The population was divided into 2 groups: A implants (n = 23) were loaded immediately on the day of surgery and group B implants (n = 19) were loaded 3 weeks after surgery. Cone beam computerized tomography (CBCT) scans were taken preoperatively to aid in treatment planning. Bone density was evaluated by tactile feedback during surgery. Insertion torque was recorded at time of implant placement. Resonance frequency analysis, performed on the day of surgery, at the time of loading, and at 6, 12, and 24 months, was used to record implant stability according to the unit's implant stability quotient (Osstell ISQ). Standardized radiographs were taken at time of implant placement and at 6, 12, and 24 months to measure crestal bone stability. Bone level changes were measured by software (Image J). Bone quality was judged as either type 1 (n = 1), 2 (n = 31), 3 (n = 15), or 4 (n = 1). There were no failures in the group A (survival = 100%, n = 23/23) and 1 failure in group B (survival = 94.7%, n = 18/19). After 2 years in function, cumulative mean radiographic bone loss was 0.75 ± 0.50mm (maxillae: 0.92 ± 0.49 mm, n = 14; mandibles: 0.67 ± 0.49 mm, n = 28). No differences in bone levels were noted between implants placed in previously augmented and nonaugmented sites, and there were no periodontal or soft tissue complications. After 2 years in function, implants partially coated with plasma-sprayed and hydrothermally treated HA were clinically predictable when restored in occlusion immediately after or within 3 weeks of implant placement.

Reliability of implant surgical guides based on soft-tissue models.

The purpose of this study was to determine the accuracy of implant surgical guides fabricated on diagnostic casts. Guides were fabricated with radiopaque rods representing implant positions. Cone beam computerized tomograms were taken with guides in place. Accuracy was evaluated using software to simulate implant placement. Twenty-two sites (47%) were considered accurate (13 of 24 maxillary and 9 of 23 mandibular sites). Soft-tissue models do not always provide sufficient accuracy for fabricating implant surgical guides.

Altered cell motility and attachment with titanium surface modifications.

BACKGROUND: Titanium implants are widely used in dentistry to replace lost teeth. Various surface modifications have been used to improve implant retention and osseointegration. This study is designed to compare the ability of three titanium surfaces to promote cell attachment and cell motility of cells relevant to periodontal tissues. METHODS: Three clinically relevant surfaces were tested: 1) machined titanium; 2) a titanium surface roughened through acid etching (dual thermal-etched titanium [DTET]); and 3) a titanium surface roughened with nanometer-scale calcium phosphate deposition (nanoscale calcium phosphate-impregnated titanium [NCPIT]). Cell attachment and migration were examined for four cell types: rat osteosarcoma cells, human osteoblasts, and gingival and periodontal ligament (PDL) fibroblasts. RESULTS: All four cell types attached to each of the three titanium surfaces equally by 2 hours, and the PDL and gingival fibroblasts generally displayed less attachment than the osteosarcoma cells and osteoblasts. The cells displayed differential motility and long-term attachment to each of the titanium surfaces. Osteosarcoma cells displayed preferential motility on NCPIT, whereas PDL fibroblasts were more motile on machined titanium, and gingival fibroblasts moved more rapidly on both DTET and NCPIT. Osteoblasts displayed little motility on any of the titanium surfaces and lost viability on NCPIT after 24 hours. Gingival fibroblasts lost attachment to machined titanium. CONCLUSIONS: Periodontal cells displayed differential motility and long-term attachment to titanium surfaces. Selective modification of titanium surface properties in various regions of an implant may be useful in guiding specific cell populations to specific locations where they might best aid in osseointegration and soft tissue remodeling.

The putative collagen-binding peptide P-15 promotes fibroblast attachment to root shavings but not hydroxyapatite.

BACKGROUND: Regenerative periodontal treatment aims to restore the attachment of the periodontal ligament and gingival collagen fibers to both the cementum of the root surface and alveolar bone. Fibroblasts are the predominant cells of the periodontal ligament and gingiva and have important roles in the function and regeneration of the tooth-supporting apparatus. This study investigated whether a putative collagen-based cell-binding peptide (P-15) increases gingival fibroblast attachment to root shavings and bone replacement graft (BRG) materials. METHODS: Gingival and dermal fibroblast attachment to root shavings and BRG materials, and cell proliferation on root shavings and sections were measured fluorometrically. Root shavings and root sections obtained from periodontally healthy teeth were treated with P-15 at 2 concentrations (200 ng/g or 400 ng/g). Citric acid (CA)-treated root materials were also compared to untreated root shavings and root sections that served as negative control groups. RESULTS: Attachment of all cells to bone fragments (whether freeze-dried or demineralized) was significantly greater than to hydroxyapatite (HA)-based BRG materials. The addition of P-15 to HA did not significantly increase gingival or dermal fibroblast attachment. At a concentration of 400 ng/g, P-15 significantly increased gingival and dermal fibroblast attachment to root shavings as compared to untreated shavings. Bone fragments, HA-based BRG materials, and untreated root shavings inhibited gingival fibroblast proliferation. Treatment of root sections with P-15 did not have any effect on gingival fibroblast proliferation. CONCLUSIONS: P-15 is a potential alternative to CA for promoting fibroblast attachment to root surfaces. However, P-15 did not enhance fibroblast proliferation on root sections.