Residual Alveolar Bone Height Research Articles

The safety of maxillary sinus floor elevation and the accuracy of implant placement using dynamic navigation.

To date, it remains a challenge to conduct maxillary sinus floor elevation (MSFE) owing to heterogeneity of anatomical structures and limited operative visibility of the maxillary sinus. The aim of this study is to investigate the safety of MSFE and the accuracy of implant placement using dynamic navigation. Forty-two implants were placed in thirty-five patients requiring implantation in posterior maxilla with dynamic navigation. They were assigned to either lateral window sinus floor elevation (LWSFE) group (n = 22) or transcrestal sinus floor elevation (TSFE) group (n = 20) according to the residual alveolar bone height (RBH). Platform deviation, apex deviation and angular deviation between actual and planned implant placement were measured in precision evaluation software. Three deviations of two groups were compared via SPSS 22.0 software. Neither accidental bleeding nor perforation of Schneiderian membrane occurred in any patients. The actual window position of LWSFE was consistent with the preoperative design. There were no significant differences in platform, apex and angular deviations between the two groups (P > 0.05). In this study the dynamic navigation harvested clinically acceptable safety of MSFE and accuracy for implant placement in posterior maxillary region. The dynamic navigation would provide the clinician with assistance in achieving precise preoperative planning and reducing complications in surgical procedures. The granular bone grafts used in the LWSFE did not significantly affection on the accuracy of the simultaneous implant placement under the guidance of dynamic navigation.

Morphometric Assessment of Alveolar Antral Artery Using Medical Computed Tomography.

This study aimed to investigate the prevalence, diameter, and position of the alveolar antral artery (AAA) in paranasal sinus computed tomography (CT) images and to correlate the location of the AAA with tooth position, the presence of teeth, and residual alveolar bone height (ABH). A retrospective study was conducted at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, from November 2016 to October 2021. CT images of 100 maxillary sinuses from 50 patients managed for modified endoscopic sinus surgery and sinus lifting by a single surgeon were selected and obtained from the Infinitt picture archiving and communication system radiology system (Infinitt Healthcare Co., Seoul, Korea). The location of the AAA in the lateral wall of the maxillary sinus was evaluated in correlation with the area of the first and second molars (M1 and M2), the presence of teeth, and the residual ABH. In this study, we found that the intraosseous type is the most common type of AAA. Furthermore, the location and distance of the AAA are significantly affected by tooth position, an edentulous state in the case of the first molar, and residual ABH. Pre-evaluation of the diameter, position, and distance to the AAA using CT images is essential to help prevent hemorrhage. The existence and wide range of the AAA distances based on the tooth position, edentulous state, and residual ABH should be considered even if CT imaging cannot locate the AAA.

Effect of Sinus Membrane Thickness on Membrane Perforation and Bone Augmentation in Transcrestal Sinus Floor Elevation: A Retrospective Study.

Sinus membrane thickening is a common maxillary sinus disease. However, a consensus has not been reached on the effect of sinus membrane thickness on the transcrestal sinus floor elevation. This retrospective study evaluated the perforation and bone formation at transcrestal sinus floor elevation sites with different sinus membrane thicknesses. A total of 117 sites in 87 patients treated with transcrestal sinus floor elevation were included in this study. The surgical sites were divided into four groups according to the baseline sinus membrane thickness: Group A (0 to 1 mm), Group B (1 to 2 mm), Group C (2 to 4 mm), and Group D (> 4 mm). CBCT scans were taken before surgery, immediately after surgery, and 6 months after surgery. The mean baseline sinus membrane thickness was 2.16 ± 2.54 mm, and the mean residual alveolar bone height was 6.58 ± 1.85 mm. The mean endosinus new bone height was 3.76 ± 1.95 mm. The perforation rate and endosinus new bone height showed no significant difference among the groups (P > .05). The incidence rates of membrane thickening and perforation were significantly higher in smoking patients (P < .05). Membrane thickening without ostium obstruction may have little impact on transcrestal sinus floor elevation surgery in regards to perforation rate and bone formation. In addition, smoking may be a risk factor for membrane thickening, and the sinus membrane is more likely to perforate during transcrestal surgery when the patient has a history of smoking.

Sinus floor augmentation using mineralized freeze-dried bone allograft combined with recombinant human bone morphogenetic protein-2 (rhBMP-2): A long-term retrospective study

Background/purposeThe combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a carrier material has not been extensively studied. This study aimed to evaluate the clinical, radiological, and histomorphometric outcomes of sinus floor augmentation using a 3:7 mixture of cancellous and cortical freeze-dried bone allografts (mixed AG) combined with rhBMP-2. Materials and methodsMixed AG was used for sinus floor augmentation in a total of 21 patients with a residual alveolar bone height <5 mm. Among the total 47 sites, augmentation with and without rhBMP-2 was performed in 26 and 21 sites, respectively. Radiographic parameters were assessed using cone-beam computed tomography. After a six-month healing period, core biopsies were harvested for histomorphometric analysis. ResultsThe bone gain after healing was 13.36 ± 3.9 mm and 12.07 ± 3.8 mm in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively. The survival rate of implants in both groups was 100% during the follow-up period. The proportion of newly formed bone was 24.6 ± 10.2% and 39.7 ± 18.3% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Moreover, the percentage of residual graft material was 21.0 ± 12.2% and 9.6 ± 10.0% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). ConclusionMixed AG combined with rhBMP-2 could be a suitable material for sinus floor augmentation. This combination may reduce the treatment time and improve the predictability of implant placement.

Minimally invasive maxillary sinus augmentation for single dental implant restoration: a case report

This clinical case aims to report a minimally invasive approach for maxillary sinus augmentation for first-molar replacement with a dental implant. A 61-year-old male presented to dental clinic with missing upper right first molar. Panoramic x-ray (OPG) showed insufficient posterior maxillary bone with a residual alveolar bone height&lt;4 mm. The patient underwent a minimally invasive sinus floor elevation and augmentation. Three months postoperatively, and a dental implant (⌀ 4.1×12 mm, bone level, straumann) was placed successfully. Thereafter, at 3-months post-implantation, the final restoration was accomplished. A 12-months follow-up demonstrated satisfactory clinical outcome. In conclusion, the present case-report demonstrates the advantages of the presented technique for sinus augmentation and dental implant restoration with high precision and promising result, in similar cases with a residual alveolar bone height &lt;5 mm.

Risk factors contributing to early implant failure following sinus augmentation: A study of a challenging cohort.

Sinus augmentation has become a more predictable and successful procedure as the knowledge of its indications and complications increased. However, knowledge of risk factors leading to early implant failure (EIF) among challenging systemic and local conditions is insufficient. The present study aims to assess risk factors for EIF following sinus augmentation in a challenging cohort. A retrospective cohort study conducted during a period of 8 years in a tertiary referral centre providing surgical and dental health care. Implant and patient variables including age, ASA (American Society of Anesthesiology) physical status classification, smoking, residual alveolar bone, type of anaesthesia and EIF were collected. Cohort was comprised of 751 implants placed in 271 individuals. EIF rates at the implant and patient level were 6.3% and 12.5%, respectively. EIF was found to be higher among smokers (patient level: χ2 (1) = 8.74, p = .003), ASA 2 physical classification patients (patient level: χ2 (2) = 6.75, p = .03), sinuses augmented under general anaesthesia (patient level: χ2 (1)=8.97, p = .003), higher bone gain (implant level: W = 12 350, p = .004), lower residual alveolar bone height (implant level: W = 13 837, p = .001) and multiple implantations (patient level: W = 3016.5, p = 0.01). However, other variables such as age, gender, collagen membrane and implant's dimensions did not reach significance. Within the limits of the study, we can conclude that smoking, ASA 2 physical status classification, general anaesthesia, low residual alveolar bone height and numerous implants are risk factors for EIF following sinus augmentation in challenging cohorts.

Application of Implant Healing Abutment Supporting Vertical Bone Augments in the Posterior Mandibular Area.

To address the problem of insufficient bone mass in the implant area, we focused on the vertical increment of the posterior mandibular area to increase bone mass with the aid of a healing abutment. Data of patients with insufficient vertical bone height in the posterior mandibular area were collected, and vertical increment of alveolar bone operations was performed with the aid of a healing abutment. Preoperative residual alveolar bone height, immediate postoperative alveolar bone height, and 6-month postoperative alveolar bone height were recorded, with peri-implant soft tissue results 6 months after surgery using the modified plaque index and sulcus bleeding index. Twelve patients, aged 42-73 years, with an average age of 55.91 ± 11.58 years, received vertical bone augmentation in the posterior mandibular region supported by implant healing abutments. Fifteen SLA TSIII OSSTEM implants were utilized in the 12 patients; one patient failed in vertical bone augmentation at one site (H0 = 0 mm). The vertical bone augmentation effect of two patients at two sites was 0 mm < H0 < 1 mm, and the vertical bone augmentation effect of 12 sites in nine patients was H0 ≥ 1 mm. The implant success rate was 93.3%, and the mean vertical bone gain was 2.91 mm. Peri-implant soft tissue parameters are as follows: mean modified plaque index, 1.92; mean modified sulcus bleeding index, 1.21; and mean probing depth, 3.18. No clinically observable complications occurred. Bone augmentation supported by the implant healing abutment showed the characteristics of "platform transfer", with good formation of the implant-bone interface. The bone augmentation surgery was completed at the same time as the implant placement, which reduced the pain of multiple operations and shortened waiting times. We provide a novel idea to solve the problem of insufficient vertical bone height in the posterior mandibular region.

Using Platelet-Rich Fibrin in Combination With Allograft Bone Particles Can Induce Bone Formation in Maxillary Sinus Augmentation

Sinus pneumatization secondary to posterior maxillary tooth extraction can hinder proper implant installation. Maxillary sinus floor augmentation is a surgical procedure that has been proposed to overcome this issue. The aim of this study was to evaluate and compare the histomorphometric outcomes of sinus floor elevation using allograft bone particles with or without platelet-rich fibrin (PRF). This randomized clinical trial included patients scheduled for maxillary sinus floor elevation in the Implant Department of Mashhad Dental School. Healthy adults with an edentulous maxilla and residual alveolar bone height of 3mm or less were eligible to participate and were randomly allocated to intervention (A) or control (B) groups. Bone biopsies were obtained 6months postoperatively. The predictor variable was using a PRF membrane for maxillary sinus augmentation. In group A, sinus floor elevation was performed using PRF combined with bone allografts, while in group B only allograft particles were used. The primary outcome variables were the recorded postoperative histologic parameters, as in the area of newly formed bone, new bone marrow, and residual graft particles (μm2). The secondary outcome variables were the radiographically measured postoperative bone height and width at the graft site. Age and sex. Independent sample t-test was employed to compare the postoperative histomorphometric parameters between groups A and B. P value ≤ .05 was considered statistically significant. A total of 20 patients (10 per group) completed the study. The mean rate of new bone formation was 43.25±5.22% in group A and 38.25±7.01% in group B. This difference was statistically insignificant (P=.087). The mean amount of newly formed bone marrow was significantly more in group A compared to group B (6.81±2.19% vs 10.23±4.49%; P=.044). The average amount of remaining particles was also significantly less in group A patients (9.35±3.43% vs 13.18±3.67%; P=.027). Incorporating PRF as an adjunctive grafting material results in fewer residual particles of allograft and in more bone marrow formation and may serve as a treatment option for developing the atrophic posterior maxilla.

Radiological Evaluation and Biomechanical Stability of Implants Simultaneously Placed at the Sites with Sole Advanced Platelet-Rich Fibrin (A-PRF) Grafted Sinus Floor.

In this retrospective study stabilities of 24 implants simultaneously placed at posterior maxillae with sinuses grafted by advanced platelet rich fibrin (A-PRF) and newly formed bone around them were evaluated. Fourteen augmented maxillary sinuses of 11 patients with a mean residual alveolar bone height of 4.55mm were involved in this study. Maxillary sinus lifting via lateral window approach and implant site osteotomy were performed, and prepared A-PRF clots were used as sole graft material. Each of the implants was immediately placed with a good primary stability. Postoperative sixth month tomography images were compared with preoperative ones in order to calculate the gained bone height and implant stability quotient (ISQ) values were recorded. The new vertical mean bone height of 24 implant sites was 12.21mm with an implant survival rate of 100%. ISQ values of the implants were ranging from 62 to 75 with a mean value of 68. Statistically the diameter of implant did not have any effect on new bone formation and the ISQ values, however the length of them did. A-PRF as a graft material for sinus lifting with simultaneous implant placement is a reliable technique with its low cost and lack of immunogenic reaction risk.

Radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning: one-year results of a randomized controlled trial

The objective of this study was to perform a comparative evaluation of the radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning (BLSFE and LSFE, respectively) when applied concomitantly with implant placement. A randomized controlled clinical trial was conducted between February 1, 2016 and May 1, 2017 including 26 individuals with at least one missing tooth. Participants were randomized 1:1 to undergo BLSFE (10 participants, 16 implants) or LSFE (13 participants, 19 implants). Bovine-derived xenograft was used in both groups and the implants were inserted concomitantly. In the BLSFE group, the antrostomy was covered with a repositioned bone window and then with a concentrated growth factors (CGF) membrane. In the LSFE group, the antrostomy was covered with a CGF membrane. Panoramic radiographs were taken before surgery (T0), immediately postoperative (T1), and at 12 months postoperative (6 months after loading) (T2). Marginal bone loss (MBL), apical bone gain, augmented alveolar bone height, and intra-sinus bone augmentation were evaluated on panoramic radiographs at T2. A linear regression analysis with generalized estimating equation models was performed. The implant survival rate was 100% at 1 year after implant surgery. The residual alveolar bone height at T0 was comparable in the BLSFE and LSFE groups (3.58 ± 1.49 mm vs 4.12 ± 1.61, P = 0.32), as was the alveolar bone height at T1 (13.61 ± 1.82 mm vs 12.38 ± 1.82 mm, P = 0.06). At T2, significantly higher alveolar bone height, intra-sinus bone augmentation, and apical bone gain, and lower distal MBL were observed in the BLSFE group when compared to the LSFE group, with adjusting for covariates (β = 2.44, 95% CI 1.42–3.46, P < 0.0001; β = 2.38, 95% CI 1.35–3.41, P < 0.0001; β = 2.33, 95% CI 1.23–3.42, P < 0.0001; and β = −0.43, 95% CI −0.83 to −0.02, P = 0.038, respectively). No significant difference was observed for mesial MBL or apical bone resorption at T2. Lateral sinus floor elevation with bone window repositioning may result in higher bone augmentation after 1 year than the traditional approach. Further research is needed to elucidate the effect of lateral sinus floor elevation with bone window repositioning.

Is There a Correlation Between Benign Paroxysmal Positional Vertigo and Indirect Sinus Lifting?

Objective: The aim of this study is to inform surgeons regarding benign paroxysmal positional vertigo (BPPV) after indirect sinus liftingprocedures and to assess its relationship with age, gender, residual alveolar bone height (RAB), and cortical thickness of the sinus floor.Methods: This study included 138 patients presenting for evaluation and management of BPPV after indirect sinus lifting. Patients withRAB lengths of 5–8 mm had been taken for indirect sinus lifting. Preoperative RAB length and cortical thickness of the sinus floor had beendetermined by cone beam computed tomography (CBCT) in each patient. The patients diagnosed with BPPV were promptly treated by anotolaryngologist. Data were assessed by descriptive statistical methods (mean ± standard deviation). Results were evaluated at the p&amp;lt;0.05significance level, in 95% confidence interval (95% CI).Results: Totally 4 out of 138 of the patients showed BPPV. There was no statistically significant difference between the mean ages and genderratio between the patients with BPPV [BPPV(+)] and without BPPV [BPPV(-)] groups. It was found that BPPV is 2.48 times more prevalent inpatients with RAB criterion values &amp;lt;5.9 mm than in patients with criterion values &amp;gt;5.9 mm. BPPV is 4.54 times more prevalent in patients witha criterion cortical thickness value &amp;gt;0.8 mm than in patients with a criterion value &amp;lt;0.8 mm.Conclusion: Based on the results of this study, patients with cortical thickness values &amp;gt;0.8 mm should be informed before undergoing surgery,and patients exhibiting postoperative symptoms associated with vertigo should be treated promptly.

Rehabilitation of Maxillary Posterior Edentulism with Direct Antroplasty and Dental Implants: A comparative analysis of two different types of bone grafts

Aims - To determine the difference in the amount of bone generated from two different sites for bilateral maxillary sinus augmentation. Introduction-Rehabilitation of the edentulous posterior maxilla with an implant supported prosthesis is a commonly occurring challenge in dental practice. Objectives - Achieving adequate height of alveolar bone for placing dental implants requires uplifting of the sinus lining in many such cases. This is generally done by harvesting bone grafts from various sites and placing it in the defect created after raising the sinus lining thus restoring the height and width of residual alveolar bone. Objectives - To determine if regional sites of bone graft harvest are equally effective when compared with distant site. Material &amp; Methods - In this series, out of 3 of our patients, two received autologous chin grafts and one patient received PCBM graft from the iliac crest. In all 3 patients, implants were placed in the second stage. Results -Acomparative analysis of the feasibility of the two techniques which involves bone grafts from two sites which have different quality of bone available over the end outcome was done and it was found that the quality of bone available for implant placement was almost the same irrespective of the graft harvest site. Conclusion - It can be safely concluded chin graft is a viable alternative to cortico-cancellous bone graft in cases of direct sinus lift procedures with minimal issues of donor site morbidity.

Prediction of Residual Alveolar Bone Height in the Posterior Maxilla After Dental Extractions

After tooth extraction in the posterior maxilla, bone resorption often limits implant placement unless additional grafting procedures are performed. However, it is difficult to predict the amount of bone that will remain after extraction based on current evidence. The purpose of this study was to develop a method for predicting the postextraction alveolar bone height in the posterior maxilla. The authors conducted a retrospective cohort study that included all patients who were treated for the extraction and replacement of a maxillary first molar with a dental implant from 2008 to 2019. Potential predictor variables included thirteen pre-extraction radiographic measurements obtained via cone-beam computed tomography. The outcome variable was having more than 6mm of bone height from the alveolar crest to the sinus floor after extraction. Decision tree analyses were used to search for the best predictors of this outcome using random forest analysis with a maximum of 3 randomly chosen covariates in each candidate tree. A total of 63 patients were included in the study; 55.6% were women, and the mean age was 57.6±14.5years. In this study population, having a bone height from the furcation to the maxillary sinus floor of <6.7mm had a 7.1% chance of having >6mm of bone height postoperatively, whereas those patients with ≥6.7mm at the same position preoperatively had a 61.9% chance of having >6mm of bone height postoperatively (P<.001). This study suggests that patients with <6.7mm of bone from the furcation to the sinus are at increased risk of having insufficient bone to support a dental implant without additional grafting at the maxillary first molar position. When treating these patients, the surgeon should consider performing a procedure at the time of extraction to increase bone height or explain additional bone grafting is expected for ideal implant placement.

Crestal approach for the repair of the Schneiderian membrane perforated during transalveolar sinus elevation

Aim The most common complication during maxillary sinus floor elevation is perforation of the Schneiderian membrane. Most of studies presented repair procedures via a lateral approach, which can induce additional complications. Therefore, in the present study the procedure was performed via crestal approach. Case report This study included three patients who showed a low residual alveolar bone height in the maxillary posterior edentulous region and in whom the placement of implants with sinus floor elevation was planned via a transalveolar approach. Perforation of the sinus membrane occurred during the procedure, and so collagen dressing material was inserted through the drilling hole to cover the perforated membrane. Xenogeneic bone was grafted under the elevated sinus membrane, and implants were placed simultaneously. The final prostheses were delivered at 6 to 8 months after the surgery. There were no complications in any of the patients. Results All implants showed successful stability, and no specific clinical or radiographic complication was observed during follow-ups lasting 2 to 3 years. Conclusion A crestal approach can be a reliable option when repairing a sinus membrane that is perforated during transalveolar sinus floor elevation.

Association between periodontal status and degree of maxillary sinus mucosal thickening: a retrospective CBCT study

BackgroundIt is well known that periodontitis can stimulate thickening of the maxillary sinus mucosa, but the association between periodontitis status and the degree of maxillary sinus mucosal thickening (maxMT) has not been reported. The objectives of this study were to investigate the effect of periodontal status of maxillary molars on the degree of maxMT.MethodsRetrospective analysis of cone-beam computed tomographic (CBCT) images of 203 periodontitis cases with maxMT. Parameters related to periodontitis in maxillary molars were measured and recorded on CBCT images. The dimension and length of the maxMT were also recorded. Multiple linear regression analysis was used to identify periodontal factors influencing the severity of maxMT, and multivariate logistic regression analysis was used to identify the odds ratio of these factors.ResultsThe factors affecting the degree of maxMT were mainly the amount of alveolar bone loss (ABL) and the minimum residual alveolar bone height (miniRABH). Compared to mild ABL, severe and moderate ABL were more likely to display severe maxMT. And the lower the miniRABH, the more severe the maxMT.ConclusionsThe severity of periodontal status of maxillary molars can influence the degree of maxMT.

Clinical Outcome of Dental Implants after Maxillary Sinus Augmentation with and without Bone Grafting: A Retrospective Evaluation.

(1) Background: The purpose of the present study was to retrospectively evaluate and compare the outcome of two sinus augmentation grafting protocols using a xenograft or blood clot alone over a 72-month follow-up. (2) Methods: Patients who received simultaneous lateral sinus floor augmentation and implant placement were included. Subjects were divided into two groups according to the grafting material, namely xenograft or blood clot, and into sub-groups based on the residual alveolar bone height (RABH) below the maxillary sinus, namely 4 to 6 mm or >6 mm. Kaplan–Meier survival estimates were calculated for each material group and for each sub-group at 1, 3, and 6 years. (3) Results: In total, 289 implants inserted in 136 patients with a one-stage procedure were considered. A total of 35 failures were registered. Overall survival rates were 94.2% for xenograft and 85.9% for blood clot alone at 1 year, 91.1% and 81.6% at 3 years, and 91.1% and 78.7% at 6 years. (4) Conclusions: In patients with 4–6 mm RABH, graftless interventions exploiting blood clot alone were not as successful as those using xenograft. When the RABH is low, sinus floor augmentation associated with grafting materials should be preferred whenever possible.

Mandibular bone height changes in two different design concepts of four implant assisted overdenture

Purpose: This comparative study was conducted to compare between two different design concepts of four implant assisted complete mandibular overdenture regarding the residual alveolar bone height changes.Materials and Methods: Ten healthy completely edentulous male patients were selected for this study. For each patient, a conventional complete denture was constructed. Each mandibular denture was duplicated to be used as a radiographic stent, then the CBCT surgical guide template was printed according to each design concept of 4-implant overdenture. The CBCT surgical guide templates were used for installing the implants according to flapless surgical technique followed by delayed loading. According to the two design concepts of the 4-implant overdenture used in this study, the patients were randomly classified into two equal groups: group [A]had two vertical canine implants with two axial 1st molar short implants (short design concept), and group [B]had two vertical canine implants with two distally inclined premolar implants (inclined design concept). Radiographic evaluations were performed immediately (T0), 6 months (T6), and 12 months (T12) respectively after picking up of the ball attachments.

Factors influencing the sinus membrane thickness in edentulous regions: a cone-beam computed tomography study

BackgroundDuring implant treatment in the maxillary molar area, maxillary sinus floor augmentation is often performed to ameliorate the reduced alveolar bone height attributable to bone remodeling and pneumatization-induced expansion of the maxillary sinus. However, this augmentation may cause complications such as misplaced implants, artery damage, and maxillary sinus mucosal perforation; infections like maxillary sinusitis; and postsurgical complications such as bone graft leakage and postoperative nasal hemorrhaging. To reduce the complications during maxillary sinus floor augmentation and postoperative infections, we performed retrospective investigations of various systemic and local factors that influence pre-operative sinus mucosal thickness (SMT) by using cone-beam computed tomography (CBCT). Subjects included patients who underwent maxillary sinus floor augmentation in an edentulous maxillary molar area with a lateral approach. Pre-operative SMT, existing bone mass, and nasal septum deviation were measured using CBCT images. Relationships between SMT and the following influencing factors were investigated: (1) age, (2) sex, (3) systemic disease, (4) smoking, (5) period after tooth extraction, (6) reason for tooth extraction, (7) residual alveolar bone height (RBH), (8) sinus septa, and (9) nasal septum deviation. Correlations were also investigated for age and RBH (p < 0.05).ResultsWe assessed 35 patients (40 sinuses; 11 male, 24 female). The average patient age was 58.90 ± 9.0 years (males, 57.9 ± 7.7 years; females, 59.9 ± 9.4 years; age range, 41–79 years). The average SMT was 1.09 ± 1.30 mm, incidence of SMT > 2 mm was 25.0%, incidence of SMT < 0.8 mm was 50.0%, and the average RBH was 2.14 ± 1.02 mm. The factors that influenced SMT included sex (p = 0.0078), period after tooth extraction (p = 0.0075), reason for tooth extraction (p = 0.020), sinus septa (p = 0.0076), and nasal septum deviation (p = 0.038).ConclusionsFactors associated with higher SMT included male sex, interval following tooth extraction < 6 months, periapical lesions, sinus septa, and nasal septum deviation. Factors associated with SMT > 2 mm were sex and reason for tooth extraction, while factors associated with SMT < 0.8 mm were time following tooth extraction and nasal septum deviation. Despite the limitations of this study, these preoperative evaluations may be of utmost importance for safely conducting maxillary sinus floor augmentation.

Comparison of 4 sinus augmentation techniques for implant placement with residual alveolar bone height ≤3 mm.

This study compared implant outcomes following maxillary sinus floor augmentation (MSFA) in edentulous patients with a residual alveolar bone height ≤3 mm. Four techniques were evaluated: 1-stage bone-added osteotome sinus floor elevation procedure (BAOSFE) with simultaneous implant placement; 2-stage BAOSFE with delayed implant placement; 1-stage lateral window sinus floor elevation with simultaneous implant placement; and 2-stage lateral window sinus floor elevation with delayed implant placement. Patients were followed for 18 to 72 months (mean: 52.5 months) after prosthesis placement. Data were analyzed with cone-beam computed tomography. A total of 96 implants from 71 patients were analyzed; pretreatment, there were no significant differences between patients. Total implant survival was 98.9%. The mean residual bone height was significantly higher in the 1-stage BAOSFE group than the other groups (P < .01); 1 implant in this group failed at 3 months. There was no significant difference in total bone height gain between groups. However, the bone height gain of 1st sinus lifting with 2-stage BAOSFE was significantly lower than the 2-stage lateral window procedure (P < .01). There was no prosthesis failure. The favorable implant outcomes suggest these 1-stage and 2-stage MSFA procedures should be considered as alternative treatment options for patients with extremely atrophic posterior maxilla.

The Influence of Residual Alveolar Bone Height on Graft Composition after Maxillary Sinus Augmentation Using Two Different Xenografts: A Histomorphometric Comparative Study.

Aim: To evaluate the hypothesis of a correlation between the preoperative residual alveolar bone height (RBH) and graft maturation after maxillary sinus floor augmentation procedures using two different bone substitutes. Methods: A total of 20 patients who underwent unilateral maxillary sinus floor augmentation with either mineralized deproteinized bovine bone (DBBM) or a xenograft enriched with polymer and gelatin (NBS) were included in this prospective study. Six months after sinus surgery, bone biopsies were harvested with a 3.2 mm diameter trephine bur, prior to dental implant placement. Histomorphometric analysis was performed, and the results were correlated with the individual RBH. Implants were loaded after 5 months of insertion, and 1-year implant success and marginal bone level change were assessed. Results: RBH was 2.17 ± 1.11 mm (range 0.5–3.5 mm) and 2.14 ± 0.72 mm (range 0.5–3.0 mm) in the NBS and DBBM group, respectively. The biopsy analyses for the DBBM group showed woven bone increases by 5.08% per 1-mm increment of RBH; medullary spaces decreased by 9.02%, osteoid decreased by 4.4%, residual biomaterial decreased by 0.34%, and lamellar bone increased by 5.68% per 1-mm increase of RBH. In the NBS group, samples showed woven bone increases by 8.08% per 1-mm increase of RBH; medullary spaces decreased by 0.38%; osteoid increased by 1.34%, residual biomaterial decreased by 0.58%, and lamellar bone decreased by 5.50% per 1-mm increase of RBH. There was no statistically significant difference in the correlation between RBH and lamellar bone, woven bone, and osteoid, independently of the material used. Implant success was 100% in both groups, and marginal bone loss was 1.02 ± 0.42 mm in DBBM and 0.95 ± 0.31 mm in the NBS group after the 1-year follow-up. Conclusion: In spite of the absence of significance, the observed trend for woven bone to increase and medullary spaces to decrease when RBH increases deserves attention. Residual bone dimension might be a determinant in the bone graft maturation after maxillary sinus augmentation.