Fernando Verdugo

The Thickness of Facial Alveolar Bone Overlying Healthy Maxillary Anterior Teeth

BACKGROUND A facial bone (<2 mm) overlying maxillary anterior teeth may be prone to resorptive processes after extraction and immediate implant placement. A thin bone contributes to risk of bone fenestration, dehiscence, and soft-tissue recession. This study measures the distance between the cemento-enamel junction (CEJ) and alveolar bone crest and the thickness of facial alveolar bone at points 1 to 5 mm from the bone crest for the six maxillary anterior teeth. METHODS Sixty-six tomographic scans (31 males and 35 females; aged 17 to 69 years; mean age: 39.9 years) of intact anterior maxilla were randomly selected and evaluated by two calibrated and independent examiners (MG and TP). RESULTS A high variation of CEJ-bone crest (0.8 to 7.2 mm) was detected. A significantly larger CEJ-bone crest was measured in smokers (P <0.05) and patients who were ≥50 years old (P <0.05). The average bone thickness at 3 mm from the CEJ for the maxillary right central incisor was 1.41 mm and for the maxillary left central incisor was 1.45 mm. For the maxillary right and left lateral incisors, the crestal bone thickness averaged 1.73 and 1.59 mm, respectively. For the maxillary right and left canines, the crestal bone thickness averaged 1.47 and 1.60 mm, respectively. CONCLUSIONS The present study supports the finding of a predominantly thin facial bone overlying the six maxillary anterior teeth. Therefore, it is essential to make informed treatment decisions based on thorough site evaluation before immediate implant placement.

Quantitation of mandibular ramus volume as a source of bone grafting.

BACKGROUND When alveolar atrophy impairs dental implant placement, ridge augmentation using mandibular ramus graft may be considered. In live patients, however, an accurate calculation of the amount of bone that can be safely harvested from the ramus has not been reported. The use of a software program to perform these calculations can aid in preventing surgical complications. PURPOSE The aim of the present study was to intra-surgically quantify the volume of the ramus bone graft that can be safely harvested in live patients, and compare it to presurgical computerized tomographic calculations. MATERIALS AND METHODS The AutoCAD software program quantified ramus bone graft in 40 consecutive patients from computerized tomographies. Direct intra-surgical measurements were recorded thereafter and compared to software data (n = 10). In these 10 patients, the bone volume was also measured at the recipient sites 6 months post-sinus augmentation. RESULTS The mandibular second and third molar areas provided the thickest cortical graft averaging 2.8 +/- 0.6 mm. The thinnest bone was immediately posterior to the third molar (1.9 +/- 0.3 mm). The volume of ramus bone graft measured by AutoCAD averaged 0.8 mL (standard deviation [SD] 0.2 mL, range: 0.4-1.2 mL). The volume of bone graft measured intra-surgically averaged 2.5 mL (SD 0.4 mL, range: 1.8-3.0 mL). The difference between the two measurement methods was significant (p < 0.001). The bone volume measured 6 months post-sinus augmentation averaged 2.2 mL (SD 0.4 mL, range: 1.6-2.8 mL) with a mean loss of 0.3 mL in volume. CONCLUSION The mandibular second molar area provided the thickest cortical graft. A cortical plate of 2.8 mm in average at combined second and third molar areas provided 2.5 mL particulated volume. The use of a design software program can improve surgical treatment planning prior to ramus bone grafting. The AutoCAD software program did not overestimate the volume of bone that can be safely harvested from the mandibular ramus.

Periodontopathogen and Epstein-Barr virus-associated periapical periodontitis may be the source of retrograde infectious peri-implantitis.

BACKGROUND Herpesviral-bacterial synergism may play a role in periodontitis and peri-implantitis etiopathogenesis. Periapical periodontitis (PP) lesions can predict future apical peri-implantitis complications. PURPOSE This pilot study aimed to substantiate herpesviral-bacterial coinfection in symptomatic (SP) and asymptomatic (AP) PP and assess associations with periodontopathogen salivary contamination in patients receiving implants. MATERIALS AND METHODS Polymerase chain reaction (PCR)-based identification was performed on PP granulation tissue (GT) from 33 SP and AP patients and compared with unstimulated whole saliva. Quantitative PCR evaluated Epstein-Barr virus (EBV) and cytomegalovirus copy counts. RESULTS SP GT had higher proportions of periodontopathogens. Symptomatic patients were 3.7 times more likely to be infected with EBV than AP (p = .07; 95% CI: 0.8-16.2). SP were 2.9, 2.1, 3.6, and 1.6 times more likely to be infected with Treponema denticola, Prevotella intermedia, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis, respectively. The odds ratio of EBV infecting PP lesions was two times higher in those positive for the virus in saliva. Saliva Tannerella forsythia-positive patients were 15 times more likely to present this pathogen in PP lesions (p = .038). Saliva EBV-positive individuals were 7 and 3.5 times more likely to yield GT contamination with T. forsythia and T. denticola, respectively. EBV copy counts were significantly higher in SP (p < .01). CONCLUSIONS A causal association between EBV, specific bacterial anaerobic infection, and symptomatic PP is likely. EBV high prevalence underscores the viral etiological importance. Salivary EBV contamination is likely to be associated with viral and bacterial GT infection. Saliva PCR analysis can be a good predictor of GT specific infection and help establish antimicrobial therapy. If confirmed by prospective longitudinal clinical trials, antiviral therapy could possibly benefit SP and nonresponsive to treatment individuals and help prevent potential peri-implant infectious complications.

Clinical, Tomographic, and Histological Assessment of Periosteal Guided Bone Regeneration with Cortical Perforations in Advanced Human Critical Size Defects

BACKGROUND Large osseous defects that fail to heal spontaneously require ridge augmentation prior to implant placement. The periosteum can act as an effective barrier membrane. Little is known about the influence of bone decortication in enhancing guided bone regeneration outcomes. PURPOSE The aim of the present study was a clinical, tomographic, and histological evaluation of bone healing in large defect sites treated with cortical perforations without the use of other membranes but the periosteum. MATERIAL AND METHODS Ten consecutive patients undergoing ridge augmentation on the pre-maxilla due to severe bone loss were followed for an average of 35 months. Recipient sites were cortico-perforated and augmented using a combination of autogenous particulate and block grafts. The periosteal membrane was preserved and it fully covered the autografts. Histological analysis was performed in four sites from a trephine core taken at the time of implant osteotomy preparation. Tomographic assessment (computed tomography [CT] scan) at baseline and post-augmentation evaluated graft volume maintenance. RESULTS Recipient sites were re-entered for implant placement showing good incorporation of the grafts with minimal volume loss. Biopsy specimens showed viable bone rich in osteoblast-like cells with little or no inflammatory cells. Clinical exam revealed absence of implant transparency, mucosal recession, mobility, bleeding on probing, or suppuration at follow-up. CT scan evaluation showed an average increased bucco-lingual width at the recipient site of 8.1 mm ± 0.9 (2.5 fold) versus a 3.2 ± 0.9 at baseline (p < .0001; CI 95%: 4.04-5.71 mm), maintaining on average 98% of the augmented width at 2.9 years. CONCLUSIONS Periosteal preservation seems to be sufficient as a barrier membrane to protect particulate or block osseous grafts provided that good primary closure is achieved. Bone decortication may enhance clinical and histological outcomes. Graft viability (biopsy specimens) and volume maintenance (CT evaluation) remained stable 35 months post-augmentation.

The Impact of Oral Contraceptives on Women's Periodontal Health and the Subgingival Occurrence of Aggressive Periodontopathogens and Candida Species

BACKGROUND The purpose of this study is to evaluate the influence of oral contraceptive (OC) use on the subgingival occurrence of specific periodontopathogens and the hosts periodontal status. METHODS Ninety-two females aged 19 to 40 years were included in the study. They were divided into two groups, OC users and non-users, and subgrouped according to the most severe periodontal condition and duration of OC usage. A pooled subgingival sample from each subject was cultured to investigate the presence of Candida species, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), and Prevotella intermedia. RESULTS OC users, particularly smokers, show a statistically significant increase in the prevalence of severe periodontitis. OC users had deeper probing depths (>or=5 mm) than non-users. Moreover, OC users had higher gingival index scores and clinical attachment loss, >or=2 and >or=5 mm, respectively, than non-users (P <0.01). Patients taking OCs had significantly higher numbers of cultures positive for Candida. Seven Candida species were isolated. Subgingival Candida was associated with P. gingivalis and P. intermedia in 82.9% and 85.4%, respectively, in patients taking OCs. A. actinomycetemcomitans was isolated in patients with moderate and severe periodontitis and was associated with subgingival P. gingivalis, P. intermedia, and Candida. CONCLUSIONS OC use may increase the risk of severe periodontitis and seems to cause a selection of certain Candida species in periodontal pockets. OC users showed a higher prevalence of P. gingivalis, P. intermedia, and A. actinomycetemcomitans compared to non-users. C. albicans, C. parapsilosis, C. krusei, C. tropicalis, and C. glabrata were the species with the ability to survive in the conditions created by the sex hormones after 3 years.

Periodontal Biotype Influence on the Volume Maintenance of Onlay Grafts

BACKGROUND Autogenous osseous transplants have advantages, including the maintenance of bone density and high concentrations of growth factors. Little is known about the potential long-term influence of periodontal biotype on the volume maintenance of block grafts. METHODS Forty patients who received autogenous block transplants prior to implant placement were included in the study. Digital photographs and periapical radiographs were taken after restoration. Clinical parameters, including bleeding on probing, mobility, suppuration, mucosal recession, and buccal tissue transparency, were recorded at yearly intervals. A computerized tomography (CT) scan was taken at an average of 42 months (n = 20) postaugmentation. RESULTS The clinical examination revealed no implant transparency, mucosal recession, mobility, bleeding on probing, or suppuration (n = 40) at 48 months. CT scans showed varying thicknesses (0.5 to 4 mm) of buccal cortical bone around the implants. The increased width at the recipient site postgraft was 7.6 mm, maintaining, on average, 98% of the augmented width. The buccal osseous thickness at the implant sites averaged 2.0 +/- 0.8 mm compared to 0.7 +/- 0.5 mm for the adjacent teeth (95% confidence interval: 0.85 to 1.65 mm; P <0.0001). Even when adjacent teeth had a thin biotype, the transplanted sites maintained statistically significant thicker buccal cortical plate at all sites (P <0.0001). CONCLUSIONS Grafted site phenotype did not seem to be influenced by the adjacent teeth biotype. Autogenous osseous transplants can predictably reconstruct function and esthetics and seemed to maintain stable bone volume around implants at an average of 3.5 years.

Bone Microbial Contamination Influences Autogenous Grafting in Sinus Augmentation

BACKGROUND The oral occurrence of putative microbial pathogens in humans has been documented in health and disease. The presence of periodontopathogens in patients with a history of periodontal disease may have a negative impact on bone regeneration. This investigation was conducted to confirm the presence of periodontal pathogens in bone particles harvested intraorally for maxillary sinus augmentation and to assess the clinical and radiographic outcomes 6 to 12 months after bone augmentation. METHODS Culture and polymerase chain reaction (PCR)-based identification were performed by paper-point sampling of intraorally harvested bone particles in a group of 12 maintenance patients undergoing maxillary sinus augmentation. Radiographs were taken to assess and compare bone healing and volume gain at baseline and at 6 to 12 months after augmentation. RESULTS The presence of periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans [previously Actinobacillus actinomycetemcomitans], Prevotella intermedia, Tannerella forsythia [previously T. forsythensis], Fusobacterium nucleatum, Parvimonas micra [previously Peptostreptococcus micros or Micromonas micros], Campylobacter rectus, enteric Gram-negative rods, and Dialister pneumosintes) was identified in 10 of 12 patients (83%) by culture, PCR, or both and was associated with greater bone volume loss at 6 months postaugmentation. The PCR-positive triad, P. gingivalis, A. actinomycetemcomitans, and P. intermedia, was associated with pronounced volume loss of the grafted sinus at 6 months. CONCLUSIONS To the best of our knowledge, this is the first study to confirm osseous microbial contamination with major periodontopathogens in individuals undergoing maxillary sinus augmentation with a history of periodontitis. The effect on the grafting outcome translated into bone volume loss in the grafted sinus 6 months postaugmentation. Specific microbial contamination may have an impact on osteogenesis in osseous regeneration.

Quantitation of Mandibular Symphysis Volume as a Source of Bone Grafting: Mandibular Symphysis Volume as a Source of Bone Grafting

BACKGROUND Autogenous intramembranous bone graft present several advantages such as minimal resorption and high concentration of bone morphogenetic proteins. A method for measuring the amount of bone that can be harvested from the symphysis area has not been reported in real patients. PURPOSE The aim of the present study was to intrasurgically quantitate the volume of the symphysis bone graft that can be safely harvested in live patients and compare it with AutoCAD (version 16.0, Autodesk, Inc., San Rafael, CA, USA) tomographic calculations. MATERIALS AND METHODS AutoCAD software program quantitated symphysis bone graft in 40 patients using computerized tomographies. Direct intrasurgical measurements were recorded thereafter and compared with AutoCAD data. The bone volume was measured at the recipient sites of a subgroup of 10 patients, 6 months post sinus augmentation. RESULTS The volume of bone graft measured by AutoCAD averaged 1.4 mL (SD 0.6 mL, range: 0.5-2.7 mL). The volume of bone graft measured intrasurgically averaged 2.3 mL (SD 0.4 mL, range 1.7-2.8 mL). The statistical difference between the two measurement methods was significant. The bone volume measured at the recipient sites 6 months post sinus augmentation averaged 1.9 mL (SD 0.3 mL, range 1.3-2.6 mL) with a mean loss of 0.4 mL. CONCLUSION AutoCAD did not overestimate the volume of bone that can be safely harvested from the mandibular symphysis. The use of the design software program may improve surgical treatment planning prior to sinus augmentation.

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.

Periodontopathogen and Epstein-Barr Virus Contamination Affects Transplanted Bone Volume in Sinus Augmentation

BACKGROUND Bone microbial contamination can impair osteogenesis. Human herpesviruses-associated vasculitis can cause vascular damage within the osseous graft and host. This study is conducted to substantiate specific contamination and assess the impact 6 months after sinus augmentation. METHODS Culture- and polymerase chain reaction (PCR)-based identification were done on harvested bone particles and unstimulated whole saliva in a group of 30 patients undergoing maxillary sinus augmentation. Patients were divided into two groups: those with and those without a history of periodontitis. Radiographic evaluation was done to assess and compare bone healing and volume gain at baseline and 6 months post-transplantation. RESULTS Seventeen patients had a history of periodontitis, and 13 did not. Ten showed culture- and PCR-negative results and belonged to the periodontally healthy group. The 17 patients with periodontitis showed culture- or PCR-positive results for the targeted periodontal pathogens. Patients with periodontitis were 2.3 times more likely to have positive salivary Epstein-Barr virus type 1 (EBV-1) than those with no history of periodontitis. The likelihood of having moderate to pronounced bone volume loss 6 months postaugmentation was 7.5 times greater in those patients presenting contamination with ≥3 specific pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, or Prevotella intermedia) versus those with only one (P <0.05). The odds ratio (OR) of pronounced volume loss was 16.3 times higher in those contaminated with a combination of salivary EBV-1 and ≥3 of the previously mentioned species versus only EBV-1 (P <0.05). Individuals showing positive salivary EBV-1 had bone bacterial contamination associated 57% of the time. The OR of having bone microbial contamination in patients with a history of periodontitis was 37.5 times higher than in individuals without periodontitis. CONCLUSIONS This study confirms contamination of bone, harvested intraorally, with key periodontopathogens in individuals undergoing sinus augmentation. Specific microbial contamination can impair osteogenesis. Saliva may act as a vehicle to transport EBV and other pathogens into the sinus. Increased bone volume loss seems to be associated with the occurrence of specific periodontal anaerobic species, salivary EBV-1, or the combination of both.