The Cortical Shield for Facial Bone Reconstruction of Severely Damaged Sockets with Simultaneous Implant Placement: A Feasibility Clinical Trial.

PURPOSE: To evaluate a novel proof-of-principle technique of simultaneous bone regeneration and implant placement in severely damaged sockets. MATERIALS AND METHODS: This study consisted of patients who required a single implant and presented with severe facial bone loss. Individuals were randomly assigned to either the immediate or delayed implant placement protocol. Socket reconstruction and simultaneous implant placement were performed through periosteal-guided bone regeneration. Implants were encased in a customized shield of autogenous cortical bone harvested from an adjacent site. Re-entry surgery was performed at 12 to 18 weeks. Peri-implant tissues and pink esthetics were assessed following established success criteria. RESULTS: Of the 34 patients treated, 28 patients-consisting of 15 women and 13 men with an average age of 50.8 ± 4.5 years-continued to the final follow-up. All individuals showed new facial cortical bone regeneration at second-stage implant surgery after an average healing time of 14.9 ± 2.2 weeks (range: 12 to 18 weeks). Implants remained stable after loading. Success rates were 100% at 12 months. Mean pink esthetic score (PES) was 7.8 ± 1.2 (range: 6 to 9 on a scale of 0 to 10). Linear regression analysis showed that provisionalization and attachment loss are independent risk factors affecting pink esthetics (P < .01). Mild and moderate/severe attachment loss decrease pink esthetic scores by 0.9 and 1.7 points, respectively (95% CI: 0.2-1.5; P < .01). The use of provisional restorations improves pink esthetic scores by 1.6 points (95% CI: 0.8-2.4; P < .001). A PES > 7 was four and five times more likely to be expected for delay and immediate implants, respectively, if the implant had a provisional restoration delivered post-second-stage (RR = 4 to 5; 95% CI: 1-31; P = .07; P = .02). Cramér's V test showed a strong association between lack of implant provisionals and low pink esthetic scores (≤ 7, value = 0.7; P = .02). Facial implant transparency at follow-up was absent, and all implants had a band of keratinized tissue > 2 mm. CONCLUSION: Facial bone regeneration and simultaneous implant placement is feasible in severely damaged sockets through periosteal-guided bone regeneration after a short healing period following immediate or delayed protocols. The assisted regenerated intrasocket bone allows for functional implant stability. Adjacent tooth attachment loss and lack of implant provisionalization negatively impacts pink esthetics. The proposed approach decreases costs, morbidity, and treatment duration and eliminates the need for multi-stage approaches.

Facial cortical bone regeneration post-extraction in non-grafted sockets allows for early implant placement and long-term functional stability.

OBJECTIVE: To evaluate posterior implant placement feasibility shortly after tooth extraction in non-grafted sockets with and without dehiscence at the time of extraction. DESIGN: Ninety-five patients requiring posterior extractions entered this cross-sectional study. They were divided in three groups after extraction: G1 without dehiscence, G2 with dehiscence ≤5 and G3 > 5 mm. CBCT were taken prior to implant placement at an average of 12-weeks post-extraction to evaluate the need for grafting, cortical bone formation and bucco-lingual width (BLW). Actual BLW (n = 60) were compared to minimum expected BLW in 3 scenarios of BLW thickness averaging 6.4-7.4-8.4 mm. Peri-implant tissues were assessed for pocket formation and inflammation following established success criteria. RESULTS: New cortical bone formation and sufficient BLW made implant placement feasible in sites with and without dehiscence at the time of extraction after an average healing time of 11.9 ± 2.4weeks (range: 8-18). Total average CBCT BLW was 10.1 ± 1.6 mm. All groups had a significantly higher BLW, than scenarios 1-3 (p < 0.0001). Molars were 20 times more likely than premolars to heal with BLW>10 mm (OR = 20; RR = 4.2; CI95 %: 5.3-74.2; p < 0.0001). Dehiscence sockets were 1.5 times more likely than non-dehiscenced sockets to present BLW ≤ 10 mm (OR = 1.5; RR = 0.6; CI95 %:0.9-2.5; p = 0.08). A band of keratinized tissue was present in all implants and success rates were 100 % at an average follow-up of 51.0 ± 23.4 months. CONCLUSION: Implant placement is feasible without socket grafting shortly after tooth extraction. Non-grafted sockets present a significant osteogenic potential. Dehiscence sockets are likely to self-repair by forming a new cortical plate. The unassisted regenerated intra-socket bone allows for functional implant stability long-term.

Marginal and internal fit of CAD/CAM frameworks in multiple implant-supported restorations: Scanning and milling error analysis.

BACKGROUND: Despite computer-aided design and computer-aided manufacturing (CAD/CAM) technology improving prosthesis fit, errors inherent to digital workflow still exist. PURPOSE: To measure scanning/milling errors, and identify factors influencing marginal (MD) and internal discrepancy (ID). MATERIALS AND METHODS: After scanning, 22 conical abutments in 5 master casts, 6 suprastructures with more than 2 implants (3, 4, and 6) were CAD designed. Angular deviation and errors in the vertical/horizontal planes were analyzed using a coordinate measuring machine (CMM). CAD suprastructures were milled and MD/ID evaluated with micro-computed tomography (CT) and optic microscopy (OM) at one screw test (OST) and final fit test (FFT). RESULTS: Mean scanning errors, at the vertical/horizontal planes, and angulation error were 3 µm ± 13, 44 µm ± 34, 0.3° ± 0.2°, respectively. Angulation errors nearly double in structures >3 abutments (0.26°vs 0.4°). OM MD in FFT/OST was 57.7 µm ± 13.9/100.7 µm ± 34.6, respectively. Micro-CT FFT-MD was 38.9 µm ± 12.8. Lineal/perimetral ID was 49.6 µm ± 11.9 and 108.2° ± 41.8, respectively. Structures >3-implants were 2.3 times more likely to present higher MD (CI95%:0.4-13.6). Nearly all the internal horizontal gap was due to scanning errors (44 of 49.6 µm). Horizontal scanning errors were three times more likely to present greater ID (CI95%:0.5-17.4). CONCLUSION: Horizontal plane scanning errors are greater than vertical errors. Scanning angulation/milling errors are higher for suprastructures>3implants. Scanning/milling errors are associated with ID/MD, respectively, leading to micro-gap formation. A CMM reduces scanning errors in >3-implant-frameworks before milling the final piece.

Long-term stable vertical bone regeneration after sinus floor elevation and simultaneous implant placement with and without grafting.

BACKGROUND: Less invasive surgical approaches to regenerate bone intra-sinus and allow long-term functional implant stability are needed. PURPOSE: To evaluate long-term vertical bone regeneration after sinus floor elevation and simultaneous implant placement with and without bone grafting. METHODS: Vertical bone gains (VBG) post-sinus elevation, with and without grafting, were evaluated in thirty individuals presenting an average residual bone height (RBH) of 4.2 mm using a standardized digital technique. Measurements were taken preoperatively, and at an average of 64.6 months follow-up. Clinically, peri-implant tissues were assessed for pocket formation and presence of inflammation to evaluate established success criteria. RESULTS: Overall, RBH averaged 4.2 ± 1.1 mm (range: 1.8-5.8) and VBG 7.7 ± 1.6 mm (range: 6.0-12.9). Mean difference of 7.6 mm between vertical bone heights (VBH) at augmented implants sites and initial RBH, 11.8 versus 4.2 mm, (P < .0001, CI95%: 6.9-8.2) was statistically significant. RBH averaged 4.5 ± 0.8 mm and 3.8 ± 1.2 (P = .07) and VBG 6.8 ± 0.5 and 8.5 ± 1.9 mm (P = .003, CI95%: 0.6-2.7), for nongrafted and grafted individuals, respectively. The grafting group received an average graft volume of 0.35 ± 0.1 cc (range: 0.25-0.5) per implant site. Long-term follow-ups average 64.6 months (range: 36-144) and all implants met the success criteria. VBG ≥ 7 mm were 7.3 times more likely to develop on grafted sites (OR = 7.3, P = 0.02, CI95%: 1.2-46.2). CONCLUSION: None to negligible amounts of grafting material are required to regenerate substantial amounts of autogenous bone into atrophic sinus cavities after simultaneous implant placement. The regenerated VBH seems stable for functional implant stability long-term. Implant success rates were 100% at an average of 64.6 months.

Autogenous bone block grafting provides facial implant tissue stability long-term.

BACKGROUND: Mucosal recession (MR) and bone loss can compromise anterior implant esthetics. PURPOSE: To evaluate tissue stability and clinical outcomes of anterior implants augmented with autogenous block transplants long-term. MATERIALS AND METHODS: This prospective cross-sectional clinical study analyzed facial tissue recession of anterior implants augmented with autogenous bone blocks and compared them to adjacent teeth in forty patients 52 months post-augmentation. Clinical parameters, MR and implant transparency, were assessed at delivery and follow-up. The hypothesis is that the facial mucosa of augmented implant sites is more resistant to trauma than the gingival margins of adjacent teeth. RESULTS: Teeth were seven times more likely to present a facial recession than adjacent augmented implants at 52-month follow-up (RR: 7; P < .001; 95%CI: 2.7-18.0). Augmented implant sites were six times more likely to present "no-tissue-recession" than adjacent teeth (RR: 6.2; P < .001; 95%CI: 2.4-15.7). Mean tooth facial tissue recession was significantly higher than adjacent implants, 1.18 ± 1.05 mm (range: 0-3.5 mm) vs. 0.06 ± 0.2 mm (95%CI: 0.8-1.5; P < .0001). Thick biotype teeth were 2 times more resistant to recession than thin biotype teeth (RR: 2.03; P = .03; 95%CI: 1.2-3.5). Implant success rates were 100%. Lack of transparency and MR at facial implant sites lasted an average of 52 months and up to 144 without signs of inflammation or pocket formation regardless of the individual's biotype. Facial bone thicknesses of 2.2 mm seem optimal for tissue stability. CONCLUSIONS: Autogenous bone block augmentation with staged implant placement seems to be a predictable, short-healing, reconstructive protocol in the esthetic zone maintaining stable peri-implant tissues long-term. Implant augmented sites seem more resistant to develop a recession than adjacent teeth.

Bone Remodeling around Implants Placed in Augmented Sinuses in Patients with and without History of Periodontitis.

BACKGROUND: Susceptible individuals may be more prone to bone loss after augmentation procedures. PURPOSE: Identify plausible clinical and biological factors influencing apical and marginal bone remodeling at implants placed in augmented sinuses, in patients with and without history of periodontitis. MATERIALS AND METHODS: This prospective cross-sectional clinical study analyzed implant bone levels in a group of 104 patients with and without history of periodontitis undergoing 139 sinus augmentation procedures. Marginal and apical bone loss (MBL/ABL) was measured post-loading using a standardized digital technique. Measurements were taken preoperatively, at second stage implant uncovery, one year after loading and at an average of 53-months follow-up. Odds ratios were calculated to evaluate risks factors of contributing variables, such as, smoking, history of periodontitis, membrane perforation, surgical approach, grafting material, use of PRP, and implant design/dimensions. RESULTS: Patients with history of periodontitis were 8.43 times more likely to present more than 2mm of MBL than patients without it (p =.041; CI95%: 1.09-65.12). Smokers were 4.97 times more likely to present over 2 mm of MBL than non-smokers (p =.003; CI95%: 1.70-14.54). Sinus membrane perforations were 11.4 times more likely to present ABL than those without perforation (p = 0.007; CI95%: 1.94-66.93). Mean MBL/ABL after 1-year post-loading and at last control were 0.49/0.56 mm and 0.67/0.46 mm, respectively. The use of a collagen membrane to cover the antrostomy and only xenograft as grafting material decreased ABL by 0.9 mm. The combination of autologous/xenograft bone was 4.04 times more likely to present higher ABL than xenograft alone (p = 0.023; CI95%: 1.21-13.45). Overall implant survival/success rates were 94.39%/91.33%, respectively. CONCLUSIONS: Smoking and previous history of periodontitis negatively affects implant MBL. Sinus membrane perforation was associated with higher ABL. Lack of association between bone remodeling at marginal and apical areas suggests that they are different and independent processes.

Systemic antibiotics and the risk of superinfection in peri-implantitis.

Peri-implantitis has emerged in the last few years as a complication difficult to resolve. The etiopathogenesis consensus is mainly attributed to bacteria. Following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, a PubMed/Medline literature search was performed using the US National Library of Medicine database up to 2015 to analyze available scientific data on the rationale and risk of superinfection associated to systemic antimicrobials in human peri-implant disease. A hand search was also conducted on relevant medical and microbiology journals. The methodological index for non-randomized studies (MINORS) was independently assessed for quality on the selected papers. Proposed combined therapies use broad-spectrum antibiotics to halt the disease progression. A major associated risk, particularly when prescribed empirically without microbiological follow-up, is the undetected development of superinfections and overgrowth of opportunistic pathogens difficult to eradicate. Peri-implant superinfections with opportunistic bacteria, yeast and viruses, are plausible risks associated to the use of systemic antibiotics in immunocompetent individuals. Lack of microbiological follow-up and antibiotic susceptibility testing may lead to ongoing microbial challenges that exacerbate the disease progression. The increased proliferation of antimicrobial resistance, modern implant surface topography and indiscriminative empiric antibiotic regimens may promote the escalation of peri-implant disease in years to come. A personalized 3-month supportive therapy may help prevent risks by sustaining a normal ecological balance, decreasing specific pathogen proportions and maintaining ideal plaque control.

Epstein-Barr virus associated peri-implantitis: a split-mouth study.

OBJECTIVES: Herpesviral-bacterial synergism may play a potential role in periodontitis and peri-implantitis (PI) etiopathogenesis. PI lesions can worsen depending on specific microbial challenge and host susceptibility. This cross-sectional split-mouth study aimed to substantiate herpesviral-bacterial co-infection in PI patients and assess associations with periodontopathogen salivary contamination. METHODS: PCR-based identification was performed on 23 patients presenting PI and contralateral healthy implants, and compared to unstimulated whole saliva. Clinical evaluation included probing depths, bleeding on probing, and suppuration. Radiographs were assessed for the presence of lamina dura and bone loss. Three sample sites per patient were tested: PI lesions, healthy implant sulci, and saliva. Quantitative PCR evaluated Epstein-Barr virus (EBV) and cytomegalovirus (CMV) copy counts. Significance of group comparisons for binary-dependent variables, within-subjects designs, was determined by McNemar's chi-square test. Risk analysis was evaluated through odds ratios (OR). RESULTS: PI lesions were 14.2 (P = 0.001; 95 % confidence interval [CI], 1.6-124.1) and 3 times (P = 0.03; 95 % CI, 0.7-11.9) more likely to harbor EBV than healthy implants and saliva, respectively. EBV positive predictive value was 90 %. PI was associated with absence of lamina dura and higher periodontopathogen proportions. Saliva sampling showed high agreement with PI bacterial detection (89-100 % rate) but not with EBV (44.4 %). The OR of PI lesions harboring Treponema denticola or Tannerella forsythia was 6.79 (P = 0.007; 95 % CI, 1.8-25.0) and 3.3 (P < 0.0001; 95 % CI, 0.3-34.3) times higher than healthy implants, respectively. Saliva of patients with PI was 5.6 times more likely to be contaminated with Prevotella nigrescens than healthy peri-implant sulci (P = 0.002). PI lesions were 1.92 times more likely to harbor Prevotella nigrescens than healthy implants (P = 0.04). CONCLUSIONS: EBV is a potential candidate in peri-implantitis etiopathogenesis. Saliva PCR analysis is useful in predicting peri-implantitis-specific bacterial infection but not EBV or CMV. CLINICAL SIGNIFICANCE: Herpesviral-bacterial synergism may favor ongoing microbial challenge in peri-implant disease and exacerbate its progression. EBV infection may explain non-responsive to treatment PI. Peri-implantitis individuals may benefit from antiviral therapy.

Bone microbial decontamination agents in osseous grafting: an in vitro study with fresh human explants.

BACKGROUND: Establishing a safe prophylactic antimicrobial protocol in bone grafting may enhance osseous volume outcomes. The purpose of this in vitro study is to assess human osteoblast response and safety after explant antimicrobial exposure. METHODS: Fresh human bone explants were exposed to three antimicrobials: povidone-iodine (PovI; 0.05%, 1%, and 5%), chlorhexidine (CHX; 0.2% and 1%), and sodium hypochlorite (NaOCl; 2.5%, 4.5%, and 5.25%) at different times (15, 30, 45, and 60 seconds) and concentrations to assess cellular toxicity. Explants were washed three times with saline after exposure. Controls, explants cultured in the absence of antimicrobials, were performed for all experimental situations tested. Trials were conducted in triplicate. Particle size influence on osteoblast growth was determined between bone fragments with a diameter <2 and ≥2 to 5 mm. Test and control groups were monitored by light microscopy to evaluate cellular growth. Osteoblast differentiation and morphology was assessed by alkaline phosphatase activity and scanning electron microscopy (SEM). RESULTS: Osteoblast growth was similar for particles <2 and ≥2 to 5 mm. Alkaline phosphatase control reference values were not significantly different from test groups (0.35 mU/mL ± 0.004 versus 0.34 mU/mL ± 0.009; P >0.05). Light microscopy showed on average 97% osteoblastic growth for bone particles exposed to PovI 5% and CHX 0.2% for all times and CHX 1% up to 30 seconds. The odds ratio of positive osteoblastic growth after a 30-second 2.5% NaOCl exposure was 2.4 times higher than after 5.25%. On average, one of two replicas yielded positive growth with 2.5% NaOCl and one of three with 5.25%. After 60-second explant exposure, positive osteoblastic growth was 7.7 times more likely to occur with 5% PovI or 0.2% CHX than with 5.25% NaOCl (P <0.05). SEM analysis confirmed light microscopy similar cellular adhesion and osteoblast phenotypic features between test and control groups. CONCLUSIONS: Best osteoblastic growth occurred after bone PovI exposure and CHX 0.2%. Cellular toxicity seems to be influenced by the type of antimicrobial, concentration, and exposure time. SEM analysis confirmed absence of osteoblast phenotypic alterations after exposure. Decontamination agents can safely be used in bone transplantation using up to 5% PovI and 0.2% CHX for 1 minute and CHX 1% for 30 seconds.

Simultaneous oral antral fistula closure and sinus floor augmentation to facilitate dental implant placement or orthodontics.

Several techniques have been used to treat the oroantral fistula with similar rates of success and failure. Some of them frequently present anatomical disadvantages. They can reduce vestibular depth, cause lack of support bone, or cause fusion of the Schneiderian and mucosal membranes. In this report, we present 3 cases of orosinusal fistulas successfully treated with a simultaneous closure of the communication and sinus floor augmentation. At the same time, this technique enables the restoration of the alveolar process with enough bone volume, which facilitates later implant surgery, prosthetic rehabilitation, or even some orthodontic treatments.

Granular cell tumor: report of 8 intraoral cases.

Granular cell tumor (GCT) is an uncommon neoplasm of controversial origin that can appear in any corporal localization, including the orofacial region. Although aggressive and malignant variants of this neoplasm have been described, most of GCTs are benign. In spite of the amount of research, the etiology of this neoplasm remains unclear and its histogenesis and its possible muscular, connective or neural origin has been broadly debated. In this paper 8 oral cases are presented, corresponding to 5 women and 3 men, with a mean age of 36.1 years old and a mean time of evolution of the lesions of 8.3 months. The most common localization was the tongue (75%). In all the cases a resection with safety margins of the lesions was carried out under local anesthesia. The samples were fixed and processed for histopathological study. The main clinicopathologic and diagnostic features of this neoplasm are reviewed and discussed.

Tumor de células granulares: presentación de 8 casoscon localización intraoral / Granular cell tumor: report of 8 intraoral cases

El Tumor de células granulares es una neoplasia de origen controvertido que puede aparecer en múltiples localizaciones corporales, incluyendo la región orofacial. El comportamiento de este infrecuente tumor es benigno en la mayor parte de los casos, aunque en ocasiones puede presentar agresividad local e incluso malignidad con afectación a distancia. Su etiología es actualmente solo parcialmente conocida y ha generado controversia desde sus primeras descripciones teorizando sobre un origen muscular, conectivo,etc o neural. En este trabajo se presentan 8 casos clínicos con localizaciónintraoral, correspondientes a 5 mujeres y 3 hombres, con una edad media de 36,1 años y en los que la localización principal fue la lengua (75%) y el tiempo medio de evolución de las lesiones fue de 8,3 meses. En todos los casos se realizó una exéresis de la lesión bajo anestesia local, con márgenes de seguridad adecuados y las muestras fueron procesadas para su estudio histopatológico. Los principales aspectos clinicopatológicos y diagnósticos en relación con esta patología son revisados y discutidos

Granular cell tumor (GCT) is an uncommon neoplasm of controversial origin that can appear in any corporal localization,including the orofacial region. Although aggressive and malignant variants of this neoplasm have been described, most of GCTs are benign. In spite of the amount of research, the etiology of this neoplasm remains unclear and its histogenesis and its possible muscular, conective or neural origin has been broadly debated. In this paper 8 oral cases are presented, corresponding to 5 women and 3 men, with a mean age of 36.1 years old and a mean time of evolution of the lesions of 8.3 months. The most common localization was the tongue (75%). In all the cases a resection with safety margins of the lesions was carried out under local anesthesia. The samples were fixed and processed for histopathological study. The main clinicopathologic and diagnostic features of this neoplasm are reviewed and discussed