Vertical Guided Bone Regeneration for a Single Missing Tooth Span with Titanium-Reinforced d-PTFE Membranes: Clinical Considerations and Observations of 10 Consecutive Cases with up to 36 Months Follow-up.

Vertical guided bone regeneration (GBR) using titanium-reinforced polytetrafluoroethylene (PTFE) membranes is a well-established technique and is considered technique sensitive. When using PTFE membranes, complications usually arise in the crestal incision or next to the neighboring tooth of the treated span. Most studies available describe either distal free end or multiple missing teeth span situations. Treating a single missing tooth span combines the challenge of two neighboring teeth and a smaller flap, which is more difficult to adapt to the augmented environment. This article describes 10 single span cases treated with vertical GBR using high-density PTFE membranes, highlighting clinical guidelines for preoperative care, flap design, and suturing.

Deproteinized bovine bone in association with guided tissue regeneration or enamel matrix derivatives procedures in aggressive periodontitis patients: a 1-year retrospective study.

OBJECTIVES: To retrospectively evaluate and compare two regenerative periodontal procedures in young individuals with aggressive periodontitis (AgP). METHODS: Thirty-two patients aged 14-25 years (mean ± SD 19.3 ± 5.7) were diagnosed as having AgP with multiple intra-bony defects (IBDs) and treated by one of two regenerative modalities of periodontal therapy: guided tissue regeneration (GTR) using deproteinized bone xenograft (DBX) particles and a resorbable membrane (the GTR group), or an application of enamel matrix derivatives (EMD) combined with DBX (the EMD/DBX group). Periodic monitoring of treated sites included recording of probing depth (PD), clinical attachment level (CAL) and gingival recession. Pre-treatment and 1-year post-operative findings were statistically analysed within and between groups. RESULTS: The PD and CAL values decreased significantly with time, but not those between study groups. The mean pre-treatment and 1-year post-treatment PDs of the IBDs of the GTR group (n = 16; sites = 67) were 8.93 ± 1.14 mm and 3.58 ± 0.50 mm, respectively, and the mean CALs were 9.03 ± 1.03 mm and 4.16 ± 0.53 mm respectively. The mean PDs of the EMD/DBX group (n = 16; sites = 73) were 8.77 ± 1.04 mm and 3.61 ± 0.36 mm, respectively, and the mean CALS were 8.79 ± 1.04 mm and 3.77 ± 0.22 mm respectively (p < 0.001 for all). CONCLUSION: Surgical treatment of AgP patients by either GTR or by application of EMD/DBX yielded similarly successful clinical results at 1-year post-treatment.

Factors affecting changes in sinus graft height between and above the placed implants.

OBJECTIVE: The aim of this study was to compare the radiographic dimensional changes of sinus graft height above and between placed implants, and evaluate the factors effecting these changes with 2 different grafting materials and both combination. STUDY DESIGN: The study group comprised 42 patients (50 sinus augmentation procedures). Four consecutive panoramic radiographs were evaluated for changes in sinus graft height between and above the placed implants. Factors that may influence graft height reduction were evaluated. RESULTS: The mean percentage of autogenous bone height reduction was 23% between implants and 13% above the implants. Bovine xenograft showed a mean of 6.5% graft height reduction between implants and 0% above implants. The only 2 parameters that correlated with reduction of graft height above and between the implants were time elapsed from surgery and the type of bone graft. Autogenous bone graft presented significantly more reduction (P = .022), whereas anorganic bovine bone graft had only minor or no changes in height. CONCLUSION: The most important factor influencing reduction in vertical bone height on the time axis, following sinus augmentation is the grafting material, followed by the presence of a functional implant. Anorganic bovine bone was found superior in graft height maintenance in an up to 10 years of follow-up.

Implant marginal bone loss in maxillary sinus grafts.

PURPOSE: The marginal bone loss (MBL) around implants placed in maxillary sinus grafts was evaluated. MATERIALS AND METHODS: The study consisted of 70 patients who had undergone 81 sinus-graft procedures (total 212 screw-type implants). Complete radiographic records were available for 160 implants, which were used to calculate MBL (follow-up 6 to 56.5 months). Habits (smoking, bruxism), surgical phase parameters (preoperative residual bone, grafting material, implant characteristics, and complications), and prosthetic parameters (crown-implant ratio, marginal fit, and opposite-arch restoration) were recorded for each patient and statistically analyzed regarding MBL. RESULTS: Cumulative survival and overall radiographic success rates were 95.5% and 83.7% for 4.5 years, respectively. Smoking, small implant surface area, and a delayed implantation approach were related to enhanced MBL, with mean MBL values of 0.24 mm/y (P < .011), 0.21 mm/y (P < .031), and 0.31 mm/y (P = .052), respectively. In residual bone of < or =4 mm, the relation to enhanced MBL was stronger (P < .018) for delayed implantation. DISCUSSION: Survival and radiographic success rates compare well with other reports. However, most studies modify success criteria regarding MBL. Smoking may be a primary risk factor regarding implant success. Implants with greater surface area values could compensate for problematic bone characteristics (e.g., in grafted maxillary sinuses). The effect of delayed implantation on MBL was surprising and may prompt simultaneous implantation whenever primary stability can be achieved. CONCLUSIONS: Smoking and implant surface area affected MBL in this patient population. Criteria for long-term implant success should be revised to a standard.

Evaluation of long-term implant success.

Implant success criteria, regarding marginal bone loss and other parameters, were first suggested in 1986 and today are still frequently referred to as the gold standard for implant success. However, according to the recent abundance of data on marginal bone loss and a better understanding of bone and soft tissue behavior around the implant neck and body, these criteria are inaccurate for the wide variety of implant systems. The purpose of this article is to review some of the relevant literature regarding marginal bone loss and to propose guidelines for a novel approach to evaluate the long-term success of implants regarding marginal bone loss. Four hypothetical patterns of implant marginal bone loss after the first year are suggested: a low-rate marginal bone loss over the years (Albrektsson's pattern); low-rate marginal bone loss in the first few years followed by a rapid loss of bone support; high-rate marginal bone loss in the first few years followed by almost no bone loss; and continuous high-rate marginal bone loss leading to a complete loss of bone support.

Smoking and complications of onlay bone grafts and sinus lift operations.

PURPOSE: To compare the incidence of complications related to onlay bone grafts (OBGs) and sinus lift operations (SLOs) among smokers and nonsmokers. MATERIALS AND METHODS: Data from 143 operations performed during the years 1995 to 2003 were analyzed. There were 64 OBGs and 79 SLOs. Patients were divided into 3 groups: nonsmokers, mild smokers (up to 10 cigarettes per day), and heavy smokers (more than 10 cigarettes per day). Duration of smoking (less or more than 10 years) was recorded. OBG complications were classified as minor (hematoma, swelling, inflammation, or temporary paresthesia) or major (graft exposure or mobility). For the SLO, perforations of the schneiderian membrane were the main intraoperative complication; postoperative complications mostly consisted of swelling, acute or chronic sinus infection, or bleeding. RESULTS: Of smokers having OBG, 50% experienced complications, compared to 23.1% of nonsmokers. Major complications were observed in one third of the smokers, compared to only 7.7% in nonsmokers. There was also a tendency toward complications in former smokers, although this relationship was not statistically significant. There was no relationship between SLO complications and smoking or a past smoking habit. DISCUSSION: In the present study, smokers demonstrated significantly higher postoperative complications following OBG operations. Smoking did not influence the results in the SLO group. There was no statistically significant difference between complications and past smoking. This finding indicates that the risk of complications can be reduced up to the normal nonsmoker complication rate when smoking ceases. CONCLUSIONS: This study established a relationship between OBG complications and smoking in this patient population. A higher incidence of complications was found in the smoking group. There was no significant influence of smoking on SLO complications.

The prevalence of surgical complications of the sinus graft procedure and their impact on implant survival.

BACKGROUND: Grafting of the maxillary sinus floor has been performed successfully over the last decade. The ultimate goal of this procedure is to allow surviving implants to support a functional prosthesis. Surgical complications of the procedure are rarely reported and their impact on implant survival has been investigated even to a lesser extent. The purpose of this study was to evaluate the prevalence of surgical complications of the sinus graft procedure and their impact on implant survival. METHODS: The study consisted of 70 patients who underwent 81 sinus graft procedures using the lateral wall approach from 1995 to 2000. A total of 212 screw-shaped implants were placed in the grafted sinuses and were restored by fixed prosthesis. Mean follow-up period for the implants was 43.6 months. Intra- and postoperative complications were thoroughly documented regarding clinical signs, times of occurrence, and treatment regimens. RESULTS: Perforation of the Schneiderian membrane was the major intraoperative complication, observed in 36 of the 81 sinuses (44%). Of the 70 patients, seven (10%) suffered from postoperative complications, specifically related to the sinus graft procedure, which included an uncommon cyst formation and an infection. Membrane perforations were strongly associated with the appearance of postoperative complications (specific and non-specific to the procedure) (P < 0.001). However, no association was found between membrane perforations or postoperative complications and implant survival. CONCLUSIONS: Intraoperative complications may lead to postoperative complications. Surgical complications did not significantly influence implant survival.