Advanced surgery II- Biological aspects, including materials. Histological results. Success/Survival rate of implants in grafted maxilla. Short Implants and Tilted Implants, Implant survival.

  • Biological aspects, including materials. Histological results.
  • Success/Survival rate of implants in grafted maxilla.
  • Short Implants and Tilted Implants, Implant survival

Rapid Search Terms

References

  1. Tarnow DP, Wallace SS, Froum SJ, Rohrer MD, Cho SC. Histologic and clinical comparison of bilateral sinus floor elevations with and without barrier membrane placement in 12 patients: Part 3 of an ongoing prospective study. Int J Periodontics Restorative Dent. 2000 Apr;20(2):117-25.
  2. Corbella S, Taschieri S, Del Fabbro M. Long-Term Outcomes for the Treatment of Atrophic Posterior Maxilla: A Systematic Review of Literature. Clin Implant Dent Relat Res. 2013 May 8.
  3. Schmitt C, Karasholi T, Lutz R, et al. Long-term changes in graft height after maxillary sinus augmentation, onlay bone grafting, and combination of both techniques: a long-term retrospective cohort study. Clin Oral Implants Res. 2012 Oct 17. doi: 10.1111/clr.12045. [Epub ahead of print]
  4. Del Fabbro M, Corbella S, Ceresoli V, Ceci C, Taschieri S. Plasma Rich in Growth Factors Improves Patients’ Postoperative Quality of Life in Maxillary Sinus Floor Augmentation: Preliminary Results of a Randomized Clinical Study. Clin Implant Dent Relat Res. 2013 Nov 12. doi: 10.1111/cid.12171. [Epub ahead of print]
  5. Boyne PJ, Lilly LC, Marx RE, Moy PK, Nevins M, Spagnoli DB, Triplett RG. De novo bone induction by recombinant human bone morphogenetic protein-2 (rhBMP-2) in maxillary sinus floor augmentation. J Oral Maxillofacial Surg 2005; 63(12):1693-1707.
  6. Maiorana C, Sommariva L, Brivio P, Sigurta D, Santoro F. Maxillary sinus augmentation with anorganic bovine bone (Bio-Oss) and autologous platelet-rich plasma: preliminary clinical and histologic evaluations. Int J Periodontics Restorative Dent 2003; 23:227-235.
  7. Schmitt CM, Doering H, et al. Histological results after maxillary sinus augmentation with Straumann® BoneCeramic, Bio-Oss®, Puros®, and autologous bone. A randomized controlled clinical trial. Clin Oral Implants Res. 2013 May;24(5):576-85.
  8. Mardinger O, Chaushu G, et al. Factors affecting changes in sinus graft height between and above the placed implants. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011 Jan;111(1):e6-11.
  9. Cha HS, Kim A, Nowzari H, Chang HS, Ahn KM. Simultaneous Sinus Lift and Implant Installation: Prospective Study of Consecutive Two Hundred Seventeen Sinus Lift and Four Hundred Sixty-Two Implants. Clin Implant Dent Relat Res. 2012 Nov 15. [Epub ahead of print]
  10. Wallace SS, Froum SJ. Effect of maxillary sinus augmentation on the survival of endosseous dental implants. A systematic review. Ann Periodontol 2003; 8:328-343.
  11. Del Fabbro M, etc. Systematic review of survival for implants placed in the grafted maxillary sinus. Int J Periodont Restorative Dent 2004; 24:565-77.
  12. Del Fabbro M, Wallace SS, Testori T. Long-term implant survival in the grafted maxillary sinus: a systematic review. Int J Periodontics Restorative Dent. 2013 Nov-Dec;33(6):773-83.
  13. Felice P, Pistilli R, Piattelli M, Soardi E, Pellegrino G, Corvino V, Esposito M. 1-stage versus 2-stage lateral maxillary sinus lift procedures: 4-month post-loading results of a multicenter randomised controlled trial. Eur J Oral Implantol. 2013 Summer;6(2):153-65.
  14. Nooh N. Effect of Schneiderian Membrane Perforation on Posterior Maxillary Implant Survival. J Int Oral Health 2013; 5(3):28-34
  15. Najm SA, Malis D, Hage ME, Rahban S, Carrel JP, Bernard JP. Potential adverse events of endosseous dental implants penetrating the maxillary sinus: Long-term clinical evaluation. Laryngoscope. 2013 Dec;123(12):2958-61. doi: 10.1002/lary.24189. Epub 2013 Oct 2.
  16. Fugazzotto PA. Shorter implants in clinical practice: rationale and treatment results. Int J Oral Maxillofac Implants. 2008 May-Jun;23(3):487-96.
  17. Pommer B, Frantal S, Willer J, Posch M, Watzek G, Tepper G. Impact of dental implant length on early failure rates: a meta-analysis of observational studies. J Clin Periodontol. 2011 Sep;38(9):856-63.
  18. Maló P, Nobre Md, Lopes A. Immediate loading of ‘All-on-4’ maxillary prostheses using trans-sinus tilted implants without sinus bone grafting: a retrospective study reporting the 3-year outcome. Eur J Oral Implantol. 2013 Autumn;6(3):273-83.
  19. Esposito M, Felice P, Worthington HV. Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus. Cochrane Database Syst Rev. 2014 May 13;5:CD008397.

 

Abstracts:

Topic:sinus floor elevation with/without barrier membrane maxillary sinus augmentation

Authors:Tarnow DP, Wallace SS, Froum SJ, Rohrer MD, Cho SC.

Title:Histologic and clinical comparison of bilateral sinus floor elevations with and without barrier membrane placement in 12 patients: Part 3 of an ongoing prospective study

Source:Int J Periodontics Restorative Dent. 2000 Apr;20(2):117-25.

Type:Prospective study (Abstract ONLY)

Rating: Good

Keywords:Sinus elevation, barrier membrane

Purpose:To evaluatethe effect of barrier membrane placement on the creation of vital bone in the grafted sinus cavity.

Materials and methods:

  • In 1993 the Department of Implant Dentistry at New York University College of Dentistry began a long-term clinical, histologic, histomorphometric, and radiographic study of the sinus elevation procedure
  • 12 patients who underwent bilateral sinus elevation surgery. In each of these 12 patients the same grafting material was used in both sinuses, making the presence or absence of an expanded polytetrafluoroethylene (e-PTFE) barrier membrane the only controlled variable.
  • A histologic and histomorphometric evaluation of healing with and without the placement of an e-PTFE barrier membrane over the lateral window at the time of sinus grafting.

Results:

(1) Placement of the barrier membrane tends to increase vital bone formation

(2) Placement of a barrier membrane has a positive effect on implant survival

(3) Membrane placement should be considered for all sinus elevation procedures.


Topic: Posterior maxilla


Authors:Corbella S, Taschieri S, Del Fabbro M.

Tittle: Long-Term Outcomes for the Treatment of Atrophic Posterior Maxilla: A Systematic Review of Literature.

Source:Clin Implant Dent Relat Res. 2013 May 8.

Type: Systematic review

Rating: Good

Keywords:maxilla, implants

Purpose:to estimate the implant survival rate in different types of techniques for the rehabilitation of posterior atrophic maxilla, after at least 3 years of follow-up.

Methods:MEDLINE database and hand searching of the relevant journals was searched using a combination of specific terms. All retrospective and prospective studies evaluating short implants in posterior maxilla, osteotome sinus floor elevation and lateral approach sinus floor elevation, and having a follow-up of at least 3 years, were included.

Results:Forty-four articles were included in the review. In four studies reporting on a total of 901 short implants (less than 10mm long, mean length around 8mm), the implant survival rate varied from 86.5% to 98.2% with up to 5 years follow-up. For the osteotome technique, 1,208 implants in eight studies were considered, showing a survival rate varying from95.4% to 100%after 3-year follow-up. Twenty-nine studies, accounting for 6,940 implants placed in 2,707 sinuses augmented through lateral techniquewere considered. Implant survival rate varied from 75.57% to 100%. Only three comparative studies were found that showed no significant difference in clinical outcomes between lateral approach and osteotome technique.

Conclusions:Sinus floor elevation with the lateral approach and with the osteotome technique is an effective and well- documented therapeutic option for the rehabilitation of atrophic posterior maxilla. The use of short implants is promising but needs further investigation to be considered as effective as the other techniques in the long term. However, the indication for the three different techniques is not perfectly equivalent and the treatment choice should be based on a careful evaluation of the individual case, in particular on the available residual bone.


Topic:Maxillary sinus augmentation need for KG around implants


Authors: Schmitt C, Karasholi T, Lutz R, Wiltfang J, Neukam F-W, Schlegel KA

Title: Long-term changes in graft height after maxillary sinus augmentation, onlay bone grafting, and combination of both techniques: a long-term retrospective cohort study.

Source: Clin Oral Implants Res. 2012 Oct 17. doi: 10.1111/clr.12045.

Type:Long-term retrospective cohort study

Reviewer:Evan Santiago

Rating:Fair

Keywords:autologous bone, bone augmentation, bone resorption, dental implant, keratinized gingiva, onlay bone grafting, sinus lift

Purpose:To examine long-term changes in graft height, implant survival rate, and peri-implant tissue conditions of dental implants place din alveolar ridges after augmentation procedures with a follow-up of 10 years

Method:25 patients with edentulous severe atrophic maxillary situations who received vertical augmentation procedures with autologous bone prior to implant placement. Patients were divided into groups (sinus elevation, onlay grafting, or a combination of both techniques). Patients were allowed to heal for 4 months and 127 implants were placed and allowed to heal for 6 months before loading. These patients were followed up clinically and radiographically followed up 1, 5, and 10 years later.

Results:Seven implants lost during observation period (94.48% 10 year survival rate). Significant bone loss occurred in the first 12 months and slowed afterwards and stabilized. After 10 years the total vertical bone loss was 27.51% after onlay grafting, 28.14% after sinus elevation, and 30.24% in the combination group (NSSD between groups). Signification positive correlations between PD and the degree of peri-implant inflammation. KG showed a statistically negative correlation to the degree of peri-implant inflammation.

Conclusion:Treatment does not impact vertical bone loss following augmentation using autologous grafts. This approach results in long term stability of dental implants. A sufficient width of keratinized peri-implant mucosa is important to prevent peri-implant bone loss and inflammation.


Topic:Growth Factors PRGF


Authors: Del FabbroM, Corbella S, Ceresoli V, Ceci C, Taschieri S

Title:Plasma Rich in Growth Factors Improves Patients’ Postoperative Quality of Life in Maxillary Sinus Floor Augmentation: Preliminary Results of a Randomized Clinical Study.

Source:Clin Implant Dent Relat Res. 2013 Nov 12. doi: 10.1111/cid.12171

Type:Clinical

Rating: Good

Keywords:growth factors, maxillary sinus augmentation, platelet concentrate, quality of life, sinus grafting

Purpose:The purpose of the present preliminary report was to assess if the use of autologous platelet concentrate during maxillary sinus augmentation may have a favorable impact on pain and other factors related to patient’s quality of life in the first week after surgery.

Method:This is an interim report of a randomized single-blind study. Fifteen patients with atrophic edentulous posterior maxilla underwent maxillary sinus augmentation using deproteinized bovine bone matrix (DBBM) as the grafting material (control group). In other 15 patients (test group), autologous plasma rich in growth factors (P-PRP) was added to DBBM, then a P-PRP clot was applied to covering the graft before suturing and finally P-PRP was placed over the suture in liquid form. During the first week postsurgery, all patients filled in a questionnaire for evaluation of main symptoms and daily activities. The outcomes of the questionnaires of the two groups were statistically compared.

Results:In the first days postsurgery, the group using P-PRP reported significantly less pain, swelling, and hematoma, and improved functional activities with respect to the control group.

Conclusion:The adjunct of P-PRP to the maxillary sinus augmentation procedure produced a beneficial effect to patients’ quality of life in the early postsurgical phase.


Topic:Sinus floor augmentation


Title: De novo bone induction by recombinant human bone morphogenetic protein-2 (rhBMP-2) in maxillary sinus floor augmentation.

Author: Boyne PJ, Lilly LC, Marx RE, Moy PK, Nevins M, Spagnoli DB, Triplett RG.

Source: J Oral Maxillofacial Surg 2005; 63(12):1693-1707.

Type:Clinical trial

Rating:Good

Keywords:sinus lift, bone graft, BMP

Purpose:This phase II study was designed to evaluate 2 concentrations of recombinant human bone morphogenetic protein-2 (rhBMP-2) for safety and efficacy in inducing adequate bone for endosseous dental implant in patients requiring staged maxillary sinus floor augmentation.

Materials and Methods:Patients were treated with rhBMP-2 (via an absorbable collagen sponge [ACS]), at concentrations of 0.75 mg/mL (n = 18), 1.50 mg/mL (n = 17), or with bone graft (n = 13). Bone induction was assessed by alveolar ridge height, width, and density measurements from computed tomography scans obtained before and 4 months after treatment and 6 months post-functional loading of dental implants (density only).

Results:Mean increases in alveolar ridge height at 4 months after treatment were similar among the groups; 11.3 mm, 9.5 mm, and 10.2 mm, respectively, in the bone graft, 0.75 mg/mL, and 1.50 mg/mL rhBMP-2/ACS treatment groups. Mean increases in alveolar ridge width (buccal to lingual) at the crest of the ridge were statistically different among the treatment groups; 4.7 mm, 2.0 mm, and 2.0 mm, respectively, in the bone graft, 0.75 mg/mL, and 1.50 mg/mL treatment groups (P <or= .01 vs 0.75 mg/mL; P < .01 vs 1.50 mg/mL). At 4 months postoperative new bone density was statistically different among the treatment groups; 350 mg/cc, 84 mg/cc, and 134 mg/cc for the bone graft, 0.75 mg/mL, and 1.50 mg/mL rhBMP-2/ACS treatment groups, respectively (P = .003 vs 0.75 mg/mL, P = .0137 vs 1.50 mg/mL, P = .0188; 1.50 mg/mL vs 0.75 mg/mL). Core bone biopsies obtained at the time of dental implant placement confirmed normal bone formation. The proportion of patients who received dental implants that were functionally loaded and remained functional at 36 months post-functional loading was 62%, 67%, and 76% in the bone graft, 0.75 mg/mL, and 1.50 mg/mL rhBMP-2/ACS treatment groups, respectively.

Conclusion:This study is the first randomized controlled trial demonstrating de novo organ tissue growth in humans from a recombinant human protein. rhBMP-2/ACS safely induced adequate bone for the placement and functional loading of endosseous dental implants in patients requiring staged maxillary sinus floor augmentation.


Topic:Maxillary sinus

Title: Maxillary sinus augmentation with anorganic bovine bone (Bio-Oss) and autologous platelet-rich plasma: preliminary clinical and histologic evaluations


Author: Maiorana C et al

Source:Int J Periodontics Restorative Dent 2003; 23:227-235.

Type:Clinical Study

Rating:Good

Keywords:PRP, BioOss, maxillary sinus augmentation

P:To describe clinical and histological evidence derived from the use of bovine bone and autologous PRP in a two stage surgical technique for maxillary sinus augmentation to avoid the use of autologous bone grafting technique.

M&M: 10 pts with posterior max atrophy recruited for bone augmentation. Eleven sinus elevation procedures were procedure according to 2 stage technique. Whole blood drawn and two centrifugation was performed and kept in continuous motion at 20 degrees Celsius until the time of surgery. BioOss and PRP gel mixed together and grafted into the sinus.

R:In all 11 cases, continuity of maxillary lateral wall was restored with tissue macroscopically similar to cortical bone in which some superficial particles of BioOss were identifiable. 3 months later CT scans showed presence and volume of graft. 6 months later, the scan showed graft to be more homogenous with reduce/resolved mucosal hypertrophy. Histomorphometric examination in 2 samples showed 40 % of the specimen composed of BioOss and newly formed bone and ratio between newly formed bone and total bone was in favor of bone regeneration. This results demonstrate osteoconductive properties of BioOss and suggest effective amplification of the bone regeneration and maturation processes evident only at 6 months after grafting procedures. Fibrin network present within PRP provides BioOss with scaffold for osteoblastic migration and platelet GF enhance the regenerative potential.


Topic:sinus lift


Authors: Schmitt CM, Doering H,

Title:Histological results after maxillary sinus augmentation with Straumann® BoneCeramic, Bio-Oss®, Puros®, and autologous bone. A randomized controlled clinical trial.

Source:Clin Oral Implants Res. 2013 May;24(5):576-85. doi: 10.1111/j.1600-0501.2012.02431.

Type:randomized clinical trial

Rating: good

Keywords:biomaterials, bone regeneration, bone substitutes, clinical research, clinical trials, guided tissue regeneration, sinus floor elevation

Purpose:To compare the clinical and histological characteristics of the tissue after sinus floor augmentation with:

  • biphasic calcium phosphate (BCP, Straumann BoneCeramic®)
  • anorganic bovine bone (ABB, Geistlich Bio-Oss®)
  • mineralized cancellous bone allograft (MCBA Zimmer Puros®)
  • autologous bone (AB)

Methods: Thirty patients with a posterior edentulous maxilla and a vertical bone height of ≤4 mm participated (45 sinuses and 94 implants in posterior maxilla). A two-stage procedure was carried out. Mucoperiosteal incision was made and Schneiderian membrane was elevated through lateral bone window. After augmentation of the maxillary sinus with ABB, BCP, MCBA, or AB followed by a healing period of 5 months, biopsies were taken from the future implant sites. Drilling with the trephine bur was performed as apically as possible. Thus, oral mucosa, residual maxillary bone, augmented sinus, and Schneiderian membrane were included in the biopsies. The trephine sites were used for implant placement after definitive treatment of the implant site. All patients received postoperative nose drops for 10 days (Otriven® nose drops 1-1-1; Novartis®) The samples were analyzed microradiographically and histologically.

Results: Course was uneventful. Although patients undergoing retromandibular bone harvesting demonstrated more swelling. Exposition of alveolar nerve occurred in 2 cases of harvesting bone block from mandible. No membrane perforations. Placement of implants was uneventful as well. 53 bone biopsies were generated from the later implant site; 41 samples were lost during removal or implant was peripheral to the augmented sinus. In total there were: 15 ABB, 14 BCP, 12 MCBA, and 12 AB samples.

Microradiography and histomorphometric analysis were carried out. Parameters for the residual bone(ROI1) and augmented sinus (ROI2) for each group were measured. (table 1)

Conclusion:Autologous bone provides the highest rate of de novo bone formation and can be considered to remain the gold standard in sinus floor augmentation. All tested control materials showed comparable results and are suitable for maxillary sinus augmentation.


Topic:Sinus Lift


Author:Mardinger O, Chaushu G.

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

Source:Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011 Jan;111(1):e6-11

Type:Longitudinal Study

Rating: Good

Keywords:Sinus lift; bone grafting; dental implants

Purpose: The aim of this study was to compare the radiographic dimensional changes of sinus graft height above and between placed implants, and to evaluate the factors effecting these changes with 2 different grafting materials and a combination of both.

Methods: The study group included 42 patients (27 F, 15M) who underwent 50 sinus augmentation procedures, with a total of 154 implants placed. Three different grafting materials were used: 1-intraoral autogenous bone alone; 2-anorganic bovine bone (Bio-oss) alone; 3-mixtures of both (20% autogenous, 80% Bio-oss). Lateral wall technique was used for all sinus lifts. Four panoramic radiographs were evaluated: Before surgery (T0); 1 year (T1); 1-5 years (T2); 5-10 years (T3) after implant placement. The following measurements were performed for analysis: 1-Vertical new bone height at the center b/t the 2 most distal implants

2-Vertical height of the grafted bone above implant

3-Residual alveolar ridge height at the center b/t the 2 most distal implants

4-Implant length

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 two 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, whereas anorganic bovine graft only had minor or no changes in height.

Discussion: The most dominant factor influencing long-term vertical stability of the grafted bone after sinus augmentation is the grafting material. Sinus grafting with bovine xenograft yields the best results regarding long-term stability of the graft height and implant survival rates. The second factor those influences stability is the presence of a functional implant. Grafted bone height maintenance was superior above the implant compared with bone height between the implants.

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.


Topic:Sinus lifts


Authors: Cha H, et al.

Title:: Prospective study of consecutive two hundred seventeen sinus lift and four hundred sixty-two implants.

Source:Clin Implant Dent Relat Res. 2012 Nov 15

Type:

Rating: Good

Keywords:Dental implants, perforation, residual alveolar bone, Schneiderian membrane, sinus lifting, smoking, xenogenic bone

Purpose:To evaluate the survival and success rates of implants simultaneously placed into grafted sinus and evaluate whether there are any differences in survival and success rates regarding residual alveolar bone height, smoking status, and membrane perforation.

Method:217 lateral window sinus lifts and 462 implants were performed by the same oral surgeon. Medical and dental histories including smoking habits were reviewed for each patient. Tapered implants (10-12 mm long) with microthreads in the coronal part with sand blasting, large grit, and acid etched surface were used. Grafting was completed with xenogenic bone (Bio-Oss) soaked in gentamycin for 5 minutes. Implants were placed initially with automated handpiece and finalized with hand wrench. Perforated membranes were repaired with porcine membrane and fibrin glue. Implants were divided into 2 groups: Group 1- implants installed in posterior maxilla with <5 mm residual bone height and Group 2- ≥ 5 mm alveolar bone height. Survival rate of each group was evaluated, as well as smoking status and membrane perforation. Uncovery was at 6 months and implants were further evaluated every 6 months for the next three years. Success was defined as absence of pain (1), infection (2), mobility (3), PA radiolucency (4), and <1.5 mm of bone resorption in the first year as well as < 0.2 mm in years following (5). Survival was indicated by the first 4 parameters only.

Results:Cumulative survival rate was 98.91%, and survival was slightly higher in group 2, though not significantly different. Cumulative success rate was 96.54% and slightly (but not significantly) higher in group 1. There was no significant difference in implant survival in perforated membranes versus non perforated membranes. There was a significant difference in smokers versus not smokers in regard to implant failure.

Conclusion: Residual alveolar bone had no significant effect on survival and success rates of implants. Sinus lifting with simultaneous implant placement reduces treatment time and number of surgeries required. Selecting and implant with characteristics that enhance initial stability is crucial for success. Membrane perforation at the time of surgery did not have an impact on implant success/survival however smoking is a possible factor for implant failure.


Topic:Advanced Surgery 2 survival rates for implants placed in the grafted maxillary sinus


Authors: Wallace SS, Froum SJ

Title:Effect of maxillary sinus augmentation on the survival of endosseous dental implants. A systematic review

Source:Annals of Periodontology, December 2003, Vol. 8, No. 1, Pages 328-343

Type:Systematic Review

Rating: Poor

KeywordsN/A

Purpose:To determine the efficacy of the sinus augmentation procedure and compare the results achieved with various surgical techniques, grafting materials and implants.

Methods:MEDLINE, the Cochrane Oral Health Group Specialized Trials Register, and the Database of Abstracts and Reviews of Effectiveness were searched for articles published through April 2003. Hand searches were conducted on Clinical Oral Implants Research, International Journal of Oral and Maxillofacial Implants, and the International Journal of Periodontics and Restorative Dentistry and the bibliographies of all relevant papers and review articles. Also, researchers, journal editors and industry sources were contacted to see if pertinent unpublished data that had been accepted for publication were available. Inclusion Criteria were: Human studies with a minimum of 20 interventions, a minimum follow-up period of1-year loading, an outcome measurement of implant survival, and published in English, regardless of the evidence level, were considered.

Results:43 studies, 3 randomized controlled clinical trials (RCTs), 5 controlled trials (CTs), 12 case series (CS), and 23 retrospective analyses (RA) were identified. 34 were lateral window interventions, 5 were osteotome interventions, 2 were localized management of the sinus floor, and 2 involved the crestal core technique.

Conclusion:

  1. Survival rate of implants placed in sinuses augmented with lateral window technique averaged 91.8% (range 61.7% and 100%)
  2. Implant survival rates compare favorably to survival rates of implants placed in non-grafted posterior maxilla.
  3. Survival rate of rough-surfaced implants is higher than machined-surfaced implants when placed in grafter sinuses.
  4. Higher survival rates of implants placed in particulate graft augmented sinuses than those placed in sinuses augmented with block grafts.
  5. Higher survival rates when a membrane was placed over the lateral window.
  6. 100% autogenous bone grafts or the inclusion of autogenous bone as a component of a composite grafe did not affect implant survival.
  7. No statistical difference between the covariates of simultaneous versus delayed implant placement, type of rough-surfaced implants, length of follow-up, year of publication and the evidence level of the study.
  8. Insufficient data were present to statistically evaluate the effects of smoking, residual crestal bone height, screw versus press-fit implant design or the effect of implant surface micromorphology other than machined versus rough surfaces.
  9. Insufficient evidence exists to recommended the utilization of platelet-rich plasma in sinus graft surgery

Topic:Grafted maxillary sinus


Authors: Del Fabro M, Testori T, Francetti L, Weinstein R.

Title:Systematic review of survival rates for implants placed in the grafted maxillary sinus.

Source:International Journal of Periodontics and Restorative Dentistry 2004; 24: 565-577.

Type:Systematic Review

Rating:Good

Keywords:maxillary sinus, sinus lift, sinus augmentation, sinus elevation, sinus graft, bone grafting, dental implants, endosseous implants

Purpose:To determine the survival rate of root-form dental implants placed in the grafted maxillary sinus. Determine effects of graft material, implant surface characteristics and simultaneous versus delayed placement on survival rate.

Materials and methods: Computer search of electronic databases from 1986 to 2002. The search was limited to human studies. Additionally a hand search was performed. Inclusion criteria: 1) at least 20 sinus elevations performed 2) mean follow up no less than 12 months of implant loading 3) fewer than 5% of patients lost to follow up 4) multiple interventions (likesimultaneous ridge augmentation) were not performed 5) access to the antrum occurred by lateral window procedure 6) grafting material and implant placement timing were clearly reported 7) type of implants used was indicated.

Results:The search yielded 252 articles. Of these, 39 met the criteria.

Within autogenous graft subgroup, the influence of using graft in a block or particulate form was examined. Survival rates of block grafts 82.9%, block plus particulate grafts 89.4%, particulate grafts alone 92.5%. This suggests that the addition of particulate grafts or use of them alone, would improve survival rates.

Conclusion:Sinus grafting is considered a safe and well-documented procedure to prepare an environment in which dental implants may have an excellent prognosis. The choice of the type of graft material and the implant micromorphology may significantly influence the outcome. The performance of rough surface implants is superior to that of smooth surface. Grafts using bone substitutes are as effective as autogenous bone.


Topic: Sinus grafting, long-term survival


Authors:Del Fabbro, Wallace, Testori

Title: Long-term implant survival in the grafted maxillary sinus: a Systematic Review

Source:Int J Perio Rest Dent. 2013 Nov-Dec;33(6):773-86

Type:systematic review

Rating:

Keywords:

Background:Maxillary sinus augmentation has been shown to be the most predictable of the preprosthetic surgical techniques used to enhance bone volume for the placement of dental implants in previously compromised sites.

Purpose:The primary purpose of this systematic review was to investigate implant survival rates based on clinical studies with a follow-up of a minimum 3 years. A further aim was to assess whether implant survival was affected by several of- ten confounding variables. Specifically researched were: type of graft material, implant surface texture, simultaneous or staged implant insertion, residual crestal bone height, use of a biologic barrier membrane, timing of implant failure, duration of follow-up, publication date, and level of evidence (study design) of included studies

Materials and Methods:The inclusion criteria of this review extended the minimum postloading evaluation to 3 years to determine if the previously reported short-term survival rates are maintained. An electronic search of the literature was performed and retrieved articles were screened using specific inclusion criteria, paramount of which was a minimum of 3 years of follow-up. The search revealed 18 articles for the lateral window approach (6,500 implants in 2,149 patients) and 7 for the transalveolar approach (1,257 implants in 704 patients).In summary, 1 RCT (4%), 3 con- trolled trials (12%), 5 case series reports (20%), and 15 retrospective studies (64%) were included.

Results:Overall, implant survival after a minimum of 3 years loading was 93.7% and 97.2% for the lateral window and transalveolar approaches, respectively. Of importance is the fact that 80% of failures occurred within the first year and 93.1% of the failures occurred within 3 years. The risk of implant failure after 3 years can now be directly calculated as the overall risk of failure after 3 years (6.3%)×the incidence of late failures (6.9%), thus equaling 0.43%.The overall implant survival using 100% autogenous bone was significantly lower than that using 100% bone substitute (P< .001; OR, 4.42; 95% CI, 3.78 to 5.06)

Conclusions:This review discredits the theory that studies of a lower level of evidence report inflated results when compared with prospective randomized controlled clinical trials.

Critique: Distinguished authors (+); confounding variables make it hard to compare (-)

One of the major problems encountered in reviews of this type is the presence of confounding variables, ie, situations in which more than one variable may affect the outcome of a procedure. It is sometimes difficult to surmount this problem because of factors such as inadequate data reporting, changes in surgical techniques over time, lack of prospective trials with only one variable, or the reality that eliminating studies with only one variable would result in a very small database.

It is quite likely that failures occurring after 3 years are the result of factors unrelated to the placement of implants into grafted sinuses. Certainly one can speculate on the possibility of implant fracture in the heavy load-bearing area of the posterior maxilla and failures resulting from peri-implantitis.


Topic:Lateral maxillary sinus lift


Authors:Felice P, Pistilli R, Piattelli M, Soardi E, Pellegrino G, Corvino V, Esposito M

Title:1-stage versus 2-stage lateral maxillary sinus lift procedures: 4-month post-loading results of a multicenter randomised controlled trial.

Source:Eur J Oral Implantol. 2013 Summer;6(2):153-65.

Type:Prospective study

Rating: Good

Keywords:anorganic bovine bone, dental implant, sinus lift, surgical procedure

Purpose: To compare the efficacy of 1-stage versus 2-stage lateral maxillary sinus lift procedures.

Materials and methods:

  • 60 partially edentulous patients requiring 1 to 3 implants and having 1 to 3mm of residual bone height and at least 5mm of bone width below the maxillary sinus, as measured on CT scans, were randomized into two equal groups to receive:
    • 1-stage lateral window sinus lift with simultaneous implant placement
    • 2-stage procedure with implant placement delayed by 4 months using a bone substitute in 3 different centers.
  • Implants were submerged for 4 months and loaded with reinforced provisional prostheses, which were replaced, after 4 months, by definitive prostheses.
  • Outcome measures were augmentation procedure failures, prosthesis failures, implant failures, complications and marginal peri-implant bone loss assessed by a blinded outcome assessor.
  • Patients were followed up to 4 months after loading. Only data of implants placed in 1 to 3mm of bone height were reported.

Results: 2 patients dropped out from the 1-stage group and none from the 2-stage group.

1 stage (n=30) 2 stage (n=30) P value
Sinus lift procedure failures NSSD (P = 1.00)
Prosthesis failure NSSD (P = 0.51).
Implant failure NSSD (P = 0.28).
Complications NSSD (P = 0.61).
Peri-implant bone loss 0.56 mm (SD: 0.36; 95% CI: -0.70 to -0.42 0.61mm (SD: 0.34; 95% CI: -0.74 to -0.48 P< 0.001

There is NSSD in bone loss between groups at loading (0.05mm).

Conclusions: NSSD were observed between implants placed according to 1- or 2-stage sinus lift procedures. However, this study may suggest that in patients having a residual bone height between 1 and 3 mm below the maxillary sinus there might be a slightly higher risk for implant failures when performing a 1-stage lateral sinus lift procedure.


Topic: Maxillary membrane perforation and implant survival


Authors:Nooh N.

Tittle:Effect of Schneiderian Membrane Perforation on Posterior Maxillary Implant Survival.

Source:J Int Oral Health 2013; 5(3):28-34

Type: Clinical study

Rating: Good

Keywords:Schneiderian membrane, implant, sinus floor, perforated membrane

Background: To assess the survival rate of implants placed in the posterior maxilla by intentionally perforating the Schneiderian membrane and protruding the implant up to 3mm beyond the sinus floor in cases of reduced crestal bone height (CBH).

Methods: 56 patients with reduced CBH received 63 implants in the posterior maxilla. All implants intentionally penetrated the Schneiderian membrane and engaged the sinus floor cortical bone. All patients were followed up and implant survival was assessed at the end of one year post implant restoration.

Results: Out of 63 implants, there was only one failure (98.4% Survival rate) after a follow up period of one year. 7 patients experienced mild epistaxis during the immediate post-operative period with no associated implant loss. One patient developed sinusitis secondary to the surgical procedure, which was treated by antibiotic therapy and the patient improved clinically with no associated implant loss.

Conclusion: An intentional perforation of the Schneiderian membrane using a 2mm twist drill at the time of implant placement and protrusion of the implant up to 3mm beyond the sinus floor does not alter the stability and outcome of dental implants, one year post-restoration. This could be associated with minor complications ranging from epistaxis to sinusitis, which are manageable.


Topic:Dental implants in maxillary sinus


Authors: Najm SA, Malis D, Hage ME, Rahban S, Carrel JP, Bernard JP

Title: Potential adverse events of endosseous dental implants penetrating the maxillary sinus: Long-term clinical evaluation.

Source: Laryngoscope. 2013 Dec;123(12):2958-61. doi: 10.1002/lary.24189

Type:Retrospective cohort study

Rating:

Keywords:Dental implant, sinus membrane perforation, maxillary sinusitis

Purpose:To evaluate the nature and incidence of long-term maxillary sinus adverse events related to endosseous implant placement with protrusion into the maxillary sinus

Method:Patients with dental implant penetrating into the maxillary sinus were included. Minimum 5 year follow-up after implant placement. Sinus assessment was both clinical and radiographic.

Results:70 patients with 83 sinus implants with sinus perforation. Mean age 65.96. 12 patients had multiple implants penetrating the sinus and another 7 had bilateral sinus perforation. Estimated penetration was under 3 mm in all cases. The average follow up was 9.98 years. During follow up there were no signs of sinusitis clinically or radiographically in any patients.

Conclusion:No sinus complications are observed when implants penetrate into the maxillary sinus. This can be attributed to maintenance of successful osseointegraiton. In the presence of an acute or chronic maxillary sinusitis the differential diagnosis must always consider other potential odontogenic and nonodontogenic etiologies.


Topic: Short Implants


Authors:Fugazzotto PA

Title:Shorter implants in clinical practice: rationale and treatment results

Source:Int J Oral Maxillofac Implants. 2008 May-Jun;23(3):487-96.

Type:Retrospective Study

Rating: Good

Keywords:osseointegrated implants, short implants, treatment planning

Purpose:The purpose of this retrospective study was to assess the survival of short implants in various clinical situations in function over time.

Method:A retrospective study was conducted of all patients treated between May 2000 and May 2007 who received endosseous implants that were less than 10 mm in length. Patient age, gender, location of implants, type of prosthesis, time in function, and stability of peri-implant crestal bone were assessed.

Results:The retrospective analysis identified 2,073 implants of 6 mm, 7 mm, 8 mm, or 9 mm in length placed in a variety of clinical situations in 1,774 patients. Cumulative implant survival rates for implants in function in various areas of the mouth supporting single crowns or short-span fixed prostheses ranged from 98.1% to 99.7%. Each indication was examined with regard to individual success and failure rates and mean time in function.

Conclusion:When utilized appropriately, implants of 6 to 9 mm in length demonstrate cumulative survival rates under function comparable to those reported for longer implants.


Topic: Implant dimension and failure


Title: Impact of dental implant length on early failure rates: a meta-analysis of observational studies.

Author: Pommer B, Frantal S, Willer J, Posch M, Watzek G, Tepper G.

Source: J Clin Periodontol. 2011 Sep;38(9):856-63.

Type:Clinical trial

Rating:Good

Keywords:implant length, implant fialure

Purpose: To test the null hypothesis of no difference in failure rates of short (minimum length: 7 mm) and longer dental implants (≥ 10 mm), a meta-analysis was performed.

Materials and Methods:A systematic search was performed to identify eligible studies. Having additional data supplied by the authors, 54 publications were included (19,083 implants).

Results:In case of mandibular implants, the null hypothesis of no impact of reduced implant length on failure within the first year of prosthetic loading could not be rejected. A significant impact of implant length could be substantiated for short machined implants in the anterior [odds ratio (OR) 5.4] and posterior maxilla (OR 3.4), while short rough-surfaced implants demonstrated increased failure rates in the anterior maxillary sites. No influence of implant diameter and denture type on the failure rate of short implants could be revealed.

Conclusion:In areas of reduced alveolar bone height the use of short dental implants may reduce the need for invasive bone augmentation procedures.


Topic:Immediate loading of Implants


Title: Immediate loading of ‘All-on-4’ maxillary prostheses using trans-sinus tilted implants without sinus bone grafting: a retrospective study reporting the 3-year outcome.

Author: Maló P et al

Source:Eur J Oral Implantol. 2013 Autumn;6(3):273-83.

Type:Clinical Study

Rating:Good

Keywords:

P: To report the outcome of trans-sinus tilted implants for the rehabilitation of the complete edentulous atrophic maxilla using the All-on-4 concept with immediate loading.

MM:This retrospective clinical study included 70 patients treated with 280 implants (Nobel Biocare), 83 of which were trans-sinus implants supporting 70 prostheses. The inclusion criteria were need of maxillary complete edentulous rehabilitation without enough bone height posterior to the canines to anchor the implants. The trans-sinus implant head was anchored on the bone available just posterior to the anterior sinus wall and inferior to the sinus floor. The trans-sinus implant body was inside the sinus, and its apex anchored in the bone between the anterior sinus wall and the nasal cortical. The nasal cortical was used, if necessary, to achieve a double bicortical anchorage. Implants were immediately loaded with cross-arch fixed prostheses. Follow-up examinations were performed after 10 days, 2, 4 and 6 months, and 1, 2 and 3 years. Radiographic evaluations were performed after 1 and 3 years of function. Outcome measures were success of the prostheses, success of the implants, complications, peri-implant marginal bone levels, and aesthetic and functional complaints. Survival was calculated at implant level and using the patient as the unit of analysis (first implant failure in any given patient) using life-table analysis.

R: Seven patients dropped out of the study. Three trans-sinus tilted implants were lost in 3 patients, giving a cumulative survival rate of 95.7% and 96.4% at patient and implant level, respectively. One conventional tilted implant was lost in 1 patient (one of the patients that lost a trans-sinus tilted implant), giving a cumulative survival rate of 98.1%. One straight implant was lost in one patient (a second patient that lost a trans-sinus implant), giving a cumulative survival rate of 98.6% and 99.3% at patient and implant level, respectively. The survival rate of prostheses was 100%. Sinusitis occurred in 2 patients (2.9%). The marginal bone resorption was on average (standard deviation) 0.96 mm (0.62 mm) and 1.14 mm (0.74 mm) for the trans-sinus tilted implants, 0.89 mm (0.54 mm) and 1.06 mm (0.71 mm) for the conventional tilted implants, and 0.62 mm (0.35 mm) and 1.15 mm (0.51 mm) for the straight implants after 1 and 3 years of follow-up, respectively.

C: The high survival rate registered at patient and implant level indicates that the outcome of immediately loaded trans-sinus implants for the rehabilitation of edentulous atrophic maxillae to avoid sinus lift procedures is a viable treatment in the short and medium term. Future studies should focus on the long-term outcome of this rehabilitation modality.


Topic:sinus lift


Authors: Esposito M, Felice P

Title:Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus.

Source:Cochrane Database Syst Rev. 2014 May 13;(5):CD008397 doi:10.1002/14651858.CD008397.pub2.

Type:systematic review

Rating: good

Keywords:sinus lift, randomized control trials, systematic review

Purpose:

  1. To assess the effects of bone augmentation vs. no augmentation in a sinus lift procedure.
  2. To compare different maxillary sinus lift techniques for dental implant rehabilitation.

Methods:a literature search was done in Cochrane, MEDLINE and EMBASE for Randomized Controlled Trials up to January 2014.

Results:

18 clinical trials met the inclusion criteria. They compared undertaking a sinus lift with not doing so, and the use of different sinus lift techniques.

Sinus lift versus no sinus lift:

Four trials with 102 participants evaluated short implants (5 to 8.5 mm long) as an alternative to sinus lift (residual height 4-9 mm). One year after loading there was no significant difference between the two procedures for prosthesis failure or implant failure. There was however an increase in complications with the sinus lift.

Different sinus lift techniques:

  • 14 trials (548 patients) compared different sinus lift techniques; bone graft versus no bone graft, autogenous bone versus bone substitute, bone graft with or without platelet-rich plasma (PRP). There was no significant difference.
  • The other comparisons with single studies were rotary versus piezo surgery to open a lateralsinus window, two different bone substitutes, use or not of a membrane, one- versus two-stage lateral sinus lift, two-stage granular bone versus one-stage autogenous bone blocks, and crestal versus lateral sinus lift; two trials compared three different crestalsinus lifting techniques: rotatory versus hand malleting (patients preferred rotatory instruments over hand malleting) and hand versus electric malleting. There was no evidence of a benefit for any sinus lift procedure compared to any other for the primary outcomes prosthesis or implant failure.

Conclusion:

  • The evidence is insufficient to determine whether sinus lift procedures in bone with residual height between 4 and 9 mm are more or less successful than placing short implants (5 to 8.5 mm) in reducing prosthesis or implant failure up to one year after loading.
  • There are more complications at sites treated with sinus lift procedures.
  • Many trials compared different sinus lift procedures and none of these indicated that one procedure reduced prosthetic or implant failures when compared to the other.
  • Patients may prefer rotary instruments over hand malleting for crestal sinus lift.