Peri-implant conditions in periodontally compromised patients following maxillary sinus augmentation. A long-term post-therapy trial

Maxillary sinus augmentation using biphasic calcium phosphate: dimensional stability results after 3-6 years

Purpose

This study was designed to observe the resorption pattern of biphasic calcium phosphate (BCP) used for maxillary sinus augmentation over a 3- to 6-year healing period, and to investigate factors affecting the resorption of BCP.

Methods

A total of 47 implants placed in 27 sinuses of 22 patients were investigated. All patients had residual bone height less than 5 mm at baseline. The modified Caldwell-Luc approach was used to elevate the maxillary sinus membrane, and the sinus cavity was filled with BCP (70% hydroxyapatite and 30% β-tricalcium phosphate). Implant placement was done simultaneously or in a staged manner. Serial radiographic analysis was performed up to 6 years postoperatively.

Results

During the follow-up period, no implant loss was reported. The mean reduced height of the augmented sinus (RHO) was 0.27±1.08 mm at 36 months, and 0.89±1.39 mm at 72 months postoperatively. Large amounts of graft material (P=0.021) and a long healing period (P=0.035) significantly influenced the amount of RHO. In particular, there was a significant relationship between a healing period longer than 40 months and RHO.

Conclusions

BCP can achieve proper dimensional stability with minimal reduction of the graft height in a 3- to 6-year healing period after maxillary sinus augmentation. The healing period and the amount of graft material influenced the resorption of BCP.

Use of sintered xenograft over allograft for ridge augmentation: technique note

Patients often present with tooth or implant complications with loss of significant bone width and the need for bone volume for implant placement and maintenance of ridge contour for esthetics. The technique described is a low-morbidity, highly predictable method to restore these sites. A case series of 12 patients followed for 2 years is presented.

The Incidence of Maxillary Sinus Membrane Perforation During Endoscopically Assessed Crestal Sinus Floor Elevation: A Pilot Study

Transcrestal sinus membrane elevation is a surgical procedure performed to increase the bone volume in the maxillary sinus cavity. Because of visual limitations, the potential for maxillary sinus membrane perforations may be greater than with the lateral approach technique. The aim of this study was to macroscopically investigate ex vivo the occurrence of sinus membrane perforation during surgery using 3 transcrestal sinus floor elevation methods. Twenty fresh human cadaver heads, with 40 intact sinuses, were used for simultaneous sinus membrane elevation, placement of graft material, and dental implants. Real-time sinus endoscopy, periapical digital radiographs, and cone-beam computerized tomography (CBCT) images were subsequently used to evaluate the outcome of each surgical procedure. Perforation rates for each of the 3 techniques were then compared using a significance level of P < .05. No statistically significant differences in the perforation rate (P = .79) were found among the 3 surgical techniques. Although the sinus endoscope noted a higher frequency of perforations at the time of implant placement as compared with instrumentation or graft insertion, the difference was not statistically significant (P = .04). The CBCT readings were judged to be more accurate for identifying evidence of sinus perforations than the periapical radiographs when compared with the direct visualization with the endoscope. This pilot study demonstrated that a sinus membrane perforation can occur at any time during the sinus lift procedure, independent of the surgical method used.

Lateral and crestal bone planing antrostomy: a simplified surgical procedure to reduce the incidence of membrane perforation during maxillary sinus augmentation procedures

This clinical report presents a simplified surgical procedure for accessing the maxillary sinus antrum via lateral and crestal approaches, which reduces the potential for sinus membrane perforation and subsequent complications when graft materials and dental implants are placed into the sinus. Due to visual limitations, perforations and associated complications can jeopardize the success rate of the graft and the implants. While there is a lack of clinical data, clinical observations suggest that the procedure, described by the authors as lateral/crestal bone planing antrostomy, can reduce the possibility of perforation of the maxillary sinus membrane during the lateral and crestal approaches to the grafting of the maxillary sinus floor. The technique involves the use of specially designed rotary instruments that plane away the bone in thinner layers, with less chance of excess bone removal and membrane perforation.

A wide-body implant as an alternative for sinus lift or bone grafting

PURPOSE

The aim was to evaluate the outcome of a short wide-body implant in the atrophic posterior jaw without a grafting procedure.

MATERIALS AND METHODS

Patients treated with a tapered wide-body implant measuring 8 to 9 mm in width and 7 to 9 mm in length (Max implant; Southern Implants, Irene, South Africa) were recalled to scrutinize implant survival. Preoperative cone beam computed tomography images were analyzed to measure bone height in reference to the mandibular canal and sinus floor.

RESULTS

There were 57 implants inserted in 18 men and 24 women after a 2-stage procedure and delayed loading. The mean follow-up was 15 months (SD, 10; range, 1-32 months), with 63.2% of the implants having at least 1 year of follow-up and 26.3% having at least 2 years' follow-up. Forty-six implants were inserted in the posterior maxilla and eleven in the mandible. Fifteen were placed in an extraction socket and forty-two in healed bone. Thirteen implants were supporting a single crown. Two implants failed, resulting in a survival rate of 96.5%, with rates of 90.9% and 97.8% for mandible and maxilla, respectively. This was not affected by gender, jaw, immediate or delayed placement, implant diameter and length, or the use of a bone substitute. The mean preoperative bone height was 7.21 mm in maxilla and 8.76 mm in mandible. In 41 cases implant length surpassed available bone height.

CONCLUSIONS

Despite the compromised bone condition and height, the survival rate of 96.5% is comparable to normal implants and, therefore, placing a wide-body implant may be an alternative to avoid grafting procedures. This is probably related to the enlarged implant surface area and the good primary stability.

Comparative radiopacity of bone graft materials

The aim of this study was to investigate the radiopacity of bone graft materials (BGMs) in comparison with bovine mandibular cortical bone and human dentine. Eight samples of each material (8 mm in diameter and 3 mm in thickness) were prepared from Dexabone(®) (DB), Bio - Oss(®) (BO), 4BONE SBS (4B), KASIOS(®) TCP (KA), S.C. PONETI (PO), and Apatite-Wollastonite (AW). The optical densities of each material, along with one tooth section (human canine tooth 1 mm slice), bovine mandibular cortical bone (BC) samples, and an aluminum step wedge, were measured from radiographic images using a transmission densitometer. The data were analyzed by nonparametric one-way ANOVA (Kruskal-Wallis) and Duncan's multiple range tests for post hoc comparison (α = 0.05). BC and AW had statistically lower optical density values than BO, 4B and human dentine (p < 0.05). Among BGMs, AW (3.681 ± 0.409 mm eq Al) had the highest radiopacity values whereas BO (1.925 ± 0.176 mm eq Al) had the lowest one. The radiopacity values of DB and KA did not reveal a statistically significant difference when compared with other materials (p > 0.05). The radiopacity of all BGMs investigated seemed to be too low to be detected radiographically when placed in the mandibular cortical bone.

A 10-year longitudinal study of 160 implants simultaneously installed in severely atrophic posterior maxillas grafted with autogenous bone and a synthetic bioactive resorbable graft

PURPOSE

This study intended to evaluate by clinical and imaging parameters the long-term predictability of osseointegrated implants inserted with specific simultaneous sinus lift approach in very atrophic posterior maxillas using a synthetic bioactive resorbable graft and autogenous bone graft.

PATIENTS AND METHODS

A total of 160 implants were inserted in 57 maxillary sinus of 45 consecutive patients (16 men, 29 women) presenting 4 mm or less of residual subsinus bone in a simultaneous approach with the sinus lift procedure. All patients were surgically treated by the same surgeon and received the same modified technical and biomaterial protocol with a composite graft made of autogenous bone and a synthetic bioactive resorbable graft (OsteoGen, Impladent, Holliswood, NY) in a 1:1 rate. Among the inclusions criteria was a minimum loading time of 6 months to assure bone response activity. All patients were followed up for a mean period of 61.7 months (range, 20-132 months) with clinical, digital pictures, and radiographic aspects. Specific cases were followed up with computerized tomography scans (27.2%) with the consent form signed.

RESULTS

Survival and success rates were 98.05% and 94.85%, respectively.

CONCLUSION

Advanced posterior maxillary resorption with extensive expanded sinus (SA-4 condition) can be safely treated by a simultaneous sinus lift approach and implant insertion using the technical protocol and biomaterials studied.

Bone-added osteotome sinus floor elevation with simultaneous placement of non-submerged sand blasted with large grit and acid etched implants: a 5-year radiographic evaluation

PURPOSE

Implant survival rates using a bone-added osteotome sinus floor elevation (BAOSFE) procedure with simultaneous placement of a non-submerged sand blasted with large grit and acid etched (SLA) implant are well documented at sites where native bone height is less than 5 mm. This study evaluated the clinical results of non-submerged SLA Straumann implants placed at the time of the BAOSFE procedure at sites where native bone height was less than 4 mm. Changes in graft height after the BAOSFE procedure were also assessed using radiographs for 5 years after the implant procedure.

METHODS

The BAOSFE procedure was performed on 4 patients with atrophic posterior maxillas with simultaneous placement of 7 non-submerged SLA implants. At least 7 standardized radiographs were obtained from each patient as follows: before surgery, immediately after implant placement, 6 months after surgery, every year for the next 3 years, and after more than 5 years had passed. Clinical and radiographic examinations were performed at every visit. Radiographic changes in graft height were calculated with respect to the implant's known length and the original sinus height.

RESULTS

All implants were stable functionally, as well as clinically and radiographically, during the follow-up. Most of the radiographic reduction in the grafted bone height occurred in the first 2 years; reduction after 2 years was slight.

CONCLUSIONS

The simultaneous placement of non-submerged SLA implants using the BAOSFE procedure is a feasible treatment option for patients with severe atrophic posterior maxillas. However, the grafted bone height is reduced during the healing period, and patients must be selected with care.

A radiographical study on the changes in height of grafting materials after sinus lift: a comparison between two types of xenogenic materials

Purpose

The performance of implant surgery in the posterior maxilla often poses a challenge due to insufficient available bone. Sinus floor elevation was developed to increase the needed vertical height to overcome this problem. However, grafting materials used for the sinus lift technique eventually show resorption. The present study radiographically compared and evaluated the changes in height of the grafting materials after carrying out maxillary sinus elevation with a window opening procedure. This study also evaluated the difference between two xenogenic bone materials when being used for the sinus lifting procedure.

Methods

Twenty-one patients were recruited for this study and underwent a sinus lift procedure. All sites were treated with either bovine bone (Bio-Oss®) with platelet-rich plasma (PRP) or bovine bone (OCS-B®)/PRP. A total of 69 implants were placed equally 6-8 months after the sinus lift. All sites were clinically and radiographically evaluated right after the implant surgery, 7-12 months, 13-24 months, and 25-48 months after their prosthetic loading.

Results

Changes of implant length/bone length with time showed a statistically significant decreasing tendency (P < 0.05). There was no significant change in the Bio-Oss® group (P > 0.05). In contrast, the OCS-B® group showed a significant decrease with time (P < 0.05). However, no significant difference was observed between the two groups (P > 0.05).

Conclusions

The results showed that there was significant reduction in comparison with data right after placement, after 7 to 12 months, 13 to 24 months, and over 25 months; however, reduction rates between each period have shown to be without significance. No significant difference in height change was observed between the Bio-Oss® and the OCS-B® groups.

Sinus floor elevation from a maxillary molar tooth extraction socket in a patient with chronic inflammation

BACKGROUND

The compromised nature of the residual interradicular bone after extraction of periodontally hopeless maxillary molars often requires a sinus elevation procedure to ideally place the implants to accept future prosthesis. Maxillary sinus elevation surgery is a procedure used to increase the volume of bone mass so that dental implants can be placed. This article documents a sinus floor elevation technique through an extraction socket in a 65-year-old white male with chronic inflammation to increase the bone mass after the extraction of a periodontally involved maxillary molar tooth.

METHODS

Computerized tomography revealed an increased thickness of the sinus membrane, which was attributed to possible chronic sinus inflammation and periodontal inflammation. After consultation with the Department of Otolaryngology, it was diagnosed as chronic inflammation without any contraindication for sinus elevation surgery or implant placement. One month after the extraction, the sinus floor elevation surgery was performed through the extraction socket, and implants were placed 4 months later.

RESULTS

An uneventful healing was noted after 6 months of osseointegration; two porcelain-fused-to-metal crowns were fabricated. Clinical follow-up took place every 3 months for 3 years, and successful healing was achieved. The patient was satisfied with the esthetic and functional results of the oral rehabilitation.

CONCLUSION

Sinus floor elevation through an extraction socket without any residual bone, followed by dental implant placement, provided successful functional results and acceptable stability.

Implant failure predictors in the posterior maxilla: a retrospective study of 273 consecutive implants

BACKGROUND

The goal of this study was to retrospectively analyze a cohort of 136 patients who underwent dental implant placement in the posterior maxilla at the University of Connecticut Health Center to assess and identify predictors for implant failure in the posterior maxilla.

METHODS

Data were retrieved from patient charts to identify subjects older than 21 years of age who received dental implant(s) in the posterior maxilla. Patients without a postoperative baseline radiograph were excluded. A recall radiograph was taken 3 to 6 months after implant placement. If there was no recall radiograph, the subject was contacted for a recall visit that included a clinical evaluation and radiographs to determine the implant status. Based on a univariate screening, variables considered potential implant failure predictors included gender, diabetes, smoking, implant length, implant diameter, membrane use, sinus-elevation technique, and surgical complications. These parameters were further assessed, and a multivariable logistic regression was performed with implant failure as a dependant variable. All tests of significance were evaluated at the 0.05 error level.

RESULTS

Two hundred seventy-three implants were placed in the posterior maxilla. Fourteen implants failed (early and late failures combined), resulting in a 94.9% overall survival rate. The survival rates for the sinus-elevation group and native bone group were 92.2% and 96.7%, respectively (P = 0.090). Based on the multivariable analysis, sinus floor-elevation procedures were not associated with increased risk for implant failure (P = 0.702). In contrast, smoking and surgical complications had a statistically significant effect on implant failure; the odds ratios for implant failure were 6.4 (P = 0.025) and 8.2 (P = 0.004), respectively.

CONCLUSION

Sinus-elevation procedures with simultaneous or staged implant placement do not increase the risk for implant failure, whereas smoking and surgical complications markedly increase the risk for implant failure.

Implant survival rates after maxillary sinus augmentation

Implant therapy in the atrophic posterior maxilla becomes challenging in the presence of reduced maxillary bone height. Sinus augmentation can be performed for resolving this condition prior to implant placement. The aim of this article was therefore to evaluate implant survival rates in the grafted sinus taking into account the influence of the implant surface, graft material, and implant placement timing. A systematic review of the literature was performed. Articles retrieved from electronic databases were screened using specific inclusion criteria, and data extracted were divided according to: graft material (autogenous, non-autogenous, composite graft), implant surface (machined or textured), and implant placement (simultaneous with grafting or delayed). Fifty-nine articles were included. Survival rates for implants placed in grafts made of bone substitutes alone and grafts of composite material were slightly better than the survival rates for implants placed in 100% autogenous grafts. Over 90% of implants associated with non-autogenous grafts had a textured surface. Textured surfaces achieved better outcomes compared with machined surfaces, and this was independent of the graft material. Simultaneous and delayed procedures had similar outcomes. It may be concluded that bone substitutes can be successfully used for sinus augmentation, reducing donor-site morbidity. Long-term studies are needed to confirm the performance of non-autogenous grafts. The use of implants with a textured surface may improve the outcome in any graft type.

A systematic review of the success of sinus floor elevation and survival of implants inserted in combination with sinus floor elevation

OBJECTIVES

The objectives of this systematic review were to assess the survival rate of grafts and implants placed with sinus floor elevation.

MATERIAL AND METHODS

An electronic search was conducted to identify studies on sinus floor elevation, with a mean follow-up time of at least 1 year after functional loading.

RESULTS

The search provided 839 titles. Full-text analysis was performed for 175 articles resulting in 48 studies that met the inclusion criteria, reporting on 12,020 implants. Meta-analysis indicated an estimated annual failure rate of 3.48% [95% confidence interval (CI): 2.48%-4.88%] translating into a 3-year implant survival of 90.1% (95% CI: 86.4%-92.8%). However, when failure rates was analyzed on the subject level, the estimated annual failure was 6.04% (95% CI: 3.87%-9.43%) translating into 16.6% (95% CI: 10.9%-24.6%) of the subjects experiencing implant loss over 3 years.

CONCLUSION

The insertion of dental implants in combination with maxillary sinus floor elevation is a predictable treatment method showing high implant survival rates and low incidences of surgical complications. The best results (98.3% implant survival after 3 years) were obtained using rough surface implants with membrane coverage of the lateral window.

Xenograft versus extraction alone for ridge preservation after tooth removal: a clinical and histomorphometric study

BACKGROUND

The preservation of bone volume immediately after tooth removal might be necessary to optimize the success of implant placement in terms of esthetics and function. The objectives of this randomized clinical trial were two-fold: 1) to compare the bone dimensional changes following tooth extraction with extraction plus ridge preservation using corticocancellous porcine bone and a collagen membrane; and 2) to analyze and compare histologic and histomorphometric aspects of the extraction-alone sites to the grafted sites.

METHODS

Forty subjects who required tooth extraction and implant placement were enrolled in this study. Using a computer-generated randomization list, the subjects were randomly assigned to the control group (EXT; extraction alone) or to the test group (RP; ridge-preservation procedure with corticocancellous porcine bone and collagen membrane). The following parameters were assessed immediately after extraction and 7 months prior to implant placement: plaque index, gingival index, bleeding on probing, horizontal ridge width, and vertical ridge changes. A bone biopsy was taken from the control and test sites 7 months after the surgical treatment. Histologic and histomorphometric analyses were also performed.

RESULTS

A significantly greater horizontal reabsorption was observed at EXT sites (4.3+/-0.8 mm) compared to RP sites (2.5+/-1.2 mm). The ridge height reduction at the buccal side was 3.6+/-1.5 mm for the extraction-alone group, whereas it was 0.7+/-1.4 mm for the ridge-preservation group. Moreover, the vertical change at the lingual sites was 0.4 mm in the ridge-preservation group and 3 mm in the extraction-alone group. Forty biopsies were harvested from the experimental sites (test and control sites). The biopsies harvested from the grafted sites revealed the presence of trabecular bone, which was highly mineralized and well structured. Particles of the grafted material could be identified in all samples. The bone formed in the control sites was also well structured with a minor percentage of mineralized bone. The amount of connective tissue was significantly higher in the extraction-alone group than in the ridge-preservation group.

CONCLUSIONS

The ridge-preservation approach using porcine bone in combination with collagen membrane significantly limited the resorption of hard tissue ridge after tooth extraction compared to extraction alone. Furthermore, the histologic analysis showed a significantly higher percentage of trabecular bone and total mineralized tissue in ridge-preservation sites compared to extraction-alone sites 7 months after tooth removal.

A comprehensive and critical review of dental implant prognosis in periodontally compromised partially edentulous patients

OBJECTIVES

The outcome of implant treatment in periodontally compromised partially edentulous patients has not been completely clarified. Therefore, the aim of the present study was to perform, applying a systematic methodology, a comprehensive and critical review of the prospective studies published in English up to and including August 2006, regarding the short-term (<5 years) and long-term (>or=5 years) prognosis of osseointegrated implants placed in periodontally compromised partially edentulous patients.

MATERIAL AND METHODS

Using The National Library Of Medicine and Cochrane Oral Health Group databases, a literature search for articles published up to and including August 2006 was performed. At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently and in duplicate by the three reviewers (I. K. K., S. K., I. F.).

RESULTS

The search provided 2987 potentially relevant titles and abstracts. At the first phase of evaluation, 2956 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 31 publications was retrieved for more detailed evaluation. Finally, 15 prospective studies were selected, including seven short-term and eight long-term studies. Because of considerable discrepancies among these studies, meta-analysis was not performed.

CONCLUSIONS

No statistically significant differences in both short-term and long-term implant survival exist between patients with a history of chronic periodontitis and periodontally healthy individuals. Patients with a history of chronic periodontitis may exhibit significantly greater long-term probing pocket depth, peri-implant marginal bone loss and incidence of peri-implantitis compared with periodontally healthy subjects. Even though the short-term implant prognosis for patients treated for aggressive periodontitis is acceptable, on a long-term basis the matter is open to question. Alterations in clinical parameters around implants and teeth in aggressive periodontitis patients may not follow the same pattern, in contrast to what has been reported for chronic periodontitis patients. However, as only three studies comprising patients treated for aggressive periodontitis were selected, more studies, specially designed, are required to evaluate implant prognosis in this subtype of periodontitis. As the selected publications exhibited considerable discrepancies, more studies, uniformly designed, preferably longitudinal, prospective and controlled, would be important.

Outcome of implant therapy in patients with previous tooth loss due to periodontitis

BACKGROUND

It is frequently debated whether implant treatment in individuals with previous tooth loss due to periodontitis is characterized by an increased incidence of implant loss and peri-implantitis.

OBJECTIVE

The objective of the present systematic review was to assess whether individuals with previous tooth loss due to periodontitis have an increased risk of loss of suprastructures, loss of implants, peri-implantitis, and peri-implant marginal bone loss as compared with individuals with previous tooth loss due to reasons other than periodontitis.

SEARCH STRATEGY

Studies considered for inclusion were searched in MEDLINE (PubMed) and relevant journals were hand searched. Moreover, reference lists of articles selected for full-text screening as well as previously published reviews relevant for the present systematic review were searched. The search was performed by one reviewer and was restricted to human studies published from January 1, 1980 to January 1, 2006. No language restrictions were applied.

SELECTION CRITERIA

Prospective and retrospective cohort studies with at least a 5-year follow-up comparing the outcome of implant treatment in individuals with periodontitis-associated and non-periodontitis-associated tooth loss, respectively, were included. The outcome measures were survival of suprastructures, survival of implants, occurrence of peri-implantitis, and peri-implant marginal bone loss. The 5- and 10-year time points were evaluated.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, methodological quality assessment, and data extraction were conducted in duplicate and independently by two of the authors. The authors were contacted for missing information. Results were expressed as random effect models using weighted mean differences for continuous outcomes and relative risk for dichotomous outcomes with 95% confidence intervals (CIs).

MAIN RESULTS

Two studies with a 5- and 10-year follow-up, respectively, were identified including a total of 33 patients with tooth loss due to periodontitis and 70 patients with non-periodontitis-associated tooth loss. There was no significant difference in the survival of the suprastructures after 5 years. Furthermore, there were no significant differences in the survival of the implants after 5 and 10 years. However, there were significantly more patients affected by peri-implantitis in the group with periodontitis-associated tooth loss during the 10-year follow-up period, risk ratio (RR) 9 (95% CI 3.94-20.57). Moreover, significantly increased peri-implant marginal bone loss was observed in patients with periodontitis-associated tooth loss after 5 years, mean difference 0.5 mm (95% CI 0.06-0.94).

CONCLUSIONS

The survival of the suprastructures and the implants was not significantly different in individuals with periodontitis-associated and non-periodontitis-associated tooth loss. However, significantly increased incidence of peri-implantitis and significantly increased peri-implant marginal bone loss were revealed in individuals with periodontitis-associated tooth loss. The small sample size and the methodological quality assessment of the two studies suggest that the results should be interpreted with caution. Consequently, further long-term studies focusing particularly on the outcome of implant treatment in young adults with aggressive periodontitis are needed before final conclusions can be drawn about the outcome of implant treatment in patients with a history of periodontitis.

Non-grafted sinus implants in periodontally compromised patients: a time-to-event analysis

This study reports the results of implant therapy involving a sinus membrane lift and of conventional implant therapy in 68 periodontally compromised patients treated between June 1990 and June 2002. Patients had at least two implants inserted, one of which was placed in the maxillary sinus region following fenestration of the lateral sinus wall and lifting of the sinus membrane. Two implant systems were used: a two-stage system (Astra) and a one-stage system (ITI). Annual follow-up visits included recording of plaque, probing pocket depth and measurement of the radiographic distance in millimeter from the implant shoulder to the alveolar crest. Survival analysis showed that the proportion of implants that had not been explanted after 5 years ranged between 88.7% for ITI sinus implants and 97% for ASTRA conventional implants. After 10 years, the proportion of implants remaining in situ ranged between 59% for ITI conventional implants and 97% for ASTRA conventional implants. Cox regression analyses showed that the factors influential for implant explantation were implant type (HR(ITI) = 2.8), implant length (HR(< or = 10 mm) = 3.1), patient being a smoker (HR(smoking) = 2.2) and patient having at least 20 natural teeth (HR(> or = 20 teeth) = 3.8). Our results demonstrate that sinus implants may be inserted with the same success as conventional implants in periodontally compromised patients.

Prevalence of maxillary sinus disease and abnormalities in patients scheduled for sinus lift procedures

BACKGROUND

The purpose of the present study was to determine the prevalence of sinus disease and abnormalities among patients scheduled to undergo direct sinus augmentation.

METHODS

Forty-five patients attending a private periodontal practice and consecutively treatment planned for sinus augmentation were referred for otorhinolaryngologic evaluation, which included a medical history and radiographic (computed tomography), clinical, and endoscopic examinations. Pathological findings were recorded and otorhinolaryngologic treatment was provided. Six months later the sinus augmentation procedure was performed and followed by postoperative evaluations for 4 to 6 months.

RESULTS

Of the 45 subjects, 98% (44) were diagnosed with chronic periodontitis, 51% were smokers, and 27% reported a history of symptoms indicative of sinus disease. Eighteen subjects were diagnosed with sinus disease and/or abnormalities. The diagnosed conditions included chronic sinusitis, sinus cysts, nasal septum deviation, and ostium stenosis. No significant differences in age, gender, or smoking status between patients with and without sinus conditions were found (P >0.05). There was a significant association between history of symptoms and diagnosis of sinus conditions (P <0.0001). Three subjects (one treated for preoperative sinus conditions) experienced notable intra- or postoperative complications related to the sinus augmentation procedure.

CONCLUSIONS

The results indicate that, in a population of patients with chronic periodontitis, presence of sinus conditions is strongly associated with a history of indicative symptoms and is independent of age, gender, and smoking status. The results reinforce the importance of careful detailed history taking and thorough clinical and radiographic evaluation prior to performing sinus augmentation.

Comparison of implant survival following sinus floor augmentation procedures with implants placed in pristine posterior maxillary bone: a systematic review

Sinus augmentation is a commonly used procedure in implant dentistry. However, a general consensus on implant survival after this procedure is still lacking. The objective of this study was to systematically review implant survival following sinus augmentation procedures compared with conventional implant placement in the posterior maxilla. Following the production of a detailed protocol, screening and quality assessments of clinical trials were conducted in duplicate and independently. The search yielded 579 abstracts and 93 were selected for full-text screening. Six publications (five studies) fulfilled all the inclusion criteria and were relevant to the study. Heterogeneity of the selected papers prevented meta-analysis. Implant survival ranged from 73% to 100% for non-augmented sinuses and from 36% to 100% for augmented sinuses in patient-based data. From implant-based data, survival varied between 75% and 100% for both non-augmented and augmented areas. Implant survival appears to show greater variability in grafted sinuses than in the posterior maxilla. However, prospective studies with larger patient numbers and control of confounding factors are urgently needed to provide definitive data on this important procedure.

A clinical long-term radiographic evaluation of graft height changes after maxillary sinus floor augmentation with a 2 : 1 autogenous bone/xenograft mixture and simultaneous placement of dental implants

The aim of the present study was to assess long-term changes in sinus-graft height after maxillary sinus floor augmentation and simultaneous placement of implants. A total of 191 patients who underwent maxillary sinus floor augmentation were radiographically followed for up to about 10 years. A 2 : 1 mixture of autogenous bone and bovine xenograft (Bio-Oss) was used as the graft material. Sinus-graft height was measured using 294 panoramic images immediately after augmentation and up to 108 months subsequently. Changes in sinus-graft height were calculated with respect to implant length and original sinus height. Patients were divided into three groups based on the height of the grafted sinus floor relative to the implant apex: Group I, in which the grafted sinus floor was above the implant apex; Group II, in which the implant apex was level with the grafted sinus floor; and Group III, in which the grafted sinus floor was below the implant apex. After augmentation, the grafted sinus floor was consistently located above the implant apex. After 2-3 years, the grafted sinus floor was level with or slightly below the implant apex. This relationship was maintained over the long term. Sinus-graft height decreased significantly and approached original sinus height. The proportion of patients classified as belonging to Group III reached a maximum from year 3 onwards. The clinical survival rate of implants was 94.2%. All implant losses occurred within 3 years after augmentation. We conclude that progressive sinus pneumatization occurs after augmentation with a 2 : 1 autogenous bone/xenograft mixture, and long-term stability of sinus-graft height represents an important factor for implant success.

[Sinus floor elevation and augmentation. Evidence-based analysis of prognosis and risk factors]

AIM

It was the aim of this investigation to analyze evidence of prognosis, predictors, and risk factors concerning sinus floor elevation and augmentation (SFEA).

MATERIALS AND METHODS

A MEDLINE search was performed to analyze the literature published between 1990 and 2002, limited to keywords ("sinus floor elevation and dental implants", "complications", "success"), study type (randomized as well as clinical prospective studies, retrospective studies, reviews), and language (German or English).

RESULTS

Of 229 publications identified, 72 met the inclusion criteria (22 prospective and 47 retrospective studies, 3 reviews). Considering the augmentation material [autogenous bone (AB), bone substitution materials (BSM), and combinations of AB and BSM], the frequency of implant loss was not significantly different (AB 8%, BSM 9%, AB + BSM 5%, p>0.09) after an observation period of 2-4 years. The average duration of the healing period was 6 months (AB) and 8 months (BSM) with simultaneous SFEA and implantation and 6-7 months (AB and BSM) for the staged approach after an average healing period of 6 months for the augmentation materials. Frequency of implant loss was not different between simultaneous and staged approaches (7-8%). Postoperative sinusitis occurred in 3-8% of the cases. Smoking, positive sinusitis history, obstructive pathoses of the nose and ostium, allergic rhino-pathoses, use of short implants (<13 mm), treatment of edentulous maxilla compared to partially edentulous maxilla, bruxism, and uncontrolled early loading of implants were identified as predictors for complications.

CONCLUSIONS

Presupposing proper consideration of indications, SFEA should be considered as an evidence-based and clinically established method for implant prosthetic rehabilitation of the atrophic posterior maxilla with an overall cumulative survival rate of 90% within an average observation period of 4 years.

Surgical therapy of peri-implant disease: a 3-year follow-up study of cases treated with 3 different techniques of bone regeneration

BACKGROUND

Advanced peri-implant intrabony defects require comprehensive surgical treatment regimens different from periodontal therapy strategies. The purpose of this longitudinal trial was to evaluate the peri-implant outcomes following guided bone regeneration with 3 treatment protocols.

METHODS

In 25 patients, 41 peri-implant defects with supporting bone loss >50% of the implant length were treated with flap surgery plus autogenous bone grafts alone (FG) (controls, n = 12) plus non-resorbable (FGM) (test 1, n = 20) or bioabsorbable barriers (FGRM) (test 2, n = 9) and supportive antimicrobial therapy. Following submerged healing, the membranes were removed (FGM), and the peri-implant probing depths (PD), probing bone levels (BL), mobility scores (PT), and intrabony defect height (DH) were radiographically evaluated at baseline, 6 months, and 1 and 3 years post-therapy.

RESULTS

Non-surgical/anti-infective therapy resulted in a limited improvement of PD scores after 6 months. At the 3-year visit, surgical treatment revealed significant changes from baseline for the controls and both of the test groups for PD: 5.1 +/- 2.7 mm (FG), 5.4 +/- 3.0 mm (FGM), and 2.6 +/- 1.6 mm (FGRM), and for BL: 3.2 +/- 2.4 mm (FG), 3.4 +/- 2.4 mm (FGM), and 2.3 +/- 1.6 mm (FGRM), Mann-Whitney test, P < or = 0.05. The changes for DH and PT were significant only for FG- and FGM-treated subjects. The overall improvement for FGRM-treated patients during the 3-year observation was less marked. However, the differences between the 3 surgical treatment protocols did not affect the treatment outcomes after 3 years.

CONCLUSIONS

Autogenous bone grafting is an appropriate treatment regimen to augment open crater-formed peri-implant defects. Although certain clinical situations require an additional fixation of barrier membranes, their routine application should be approached with caution.