Posterior Maxillary Ridge Research Articles

Trans-crestal dental implants in the rehabilitation of a severely atrophic maxilla: A retrospective case series.

To evaluate the mid-term clinical and radiographic results of immediate fixed full-arch prosthesis supported by two anterior axial and two posterior trans-crestally placed tilted implants in patients with severely atrophic posterior maxilla. Patients with posterior maxillary ridge less than 4 mm high and 3 mm wide were rehabilitated with an immediate fixed provisional prosthesis supported by two anterior axially placed and two trans-crestal posterior tilted implants within 3 h after implant surgery. The final prosthesis, consisting of a CAD-CAM titanium framework and composite teeth was delivered 6 months later. Patients were scheduled for follow-up visits every 6 months to assess clinical and radiological parameters. Patients' satisfaction was assessed by a questionnaire up to 5 years. From April 2008 to May 2017, 56 implants (28 axial and 28 tilted) were inserted in 14 subjects (eight female and six male). The average bone loss for the anterior axial implants was 0.99 ± 0.19 mm at 1 year (n = 28 implants), 1.37 ± 0.31 mm at 5 years (n = 28), and 2.05 ± 0.32 mm at 10 years (n = 14). Only for three implants in two subjects the marginal bone loss was higher than 2 mm after 60 months. No implant was lost, and no prosthetic failure occurred after a mean follow-up of 125 months (range 79-186 months), leading to 100% implant and prosthesis survival rates. The upper 95% confidence limit of the failure rate was 23% and 6% at patient and implant level, respectively. High level of satisfaction was reported at 5-year follow-up. Wider sample sizes will be required to determine whether the presented technique is a reliable treatment option for the immediate rehabilitation of the atrophic maxilla.

Closed sinus lift and fixed prostheses versus implant-assisted overdentures in management of atrophied distal extension maxillary ridges: A one-year randomized clinical trial

Rehabilitation of elderly or medically compromised patients with an atrophied unilateral posterior maxillary ridge by an implant-supported prosthesis may be complicated by maxillary sinus pneumatization with insufficient bone for implant placement. This short-term clinical trial assessed clinical results of closed sinus lift and fixed prosthesis versus implant-assisted overdentures in the management of participants with atrophied distal extension maxillary ridges. Forty participants with unilateral atrophying distal extension maxillary ridges were randomly assigned into 2 groups. The CSL group (n=20) participants received fixed prostheses supported by 3 implants following a closed sinus lift. The IOD group (n=20) participants received removable partial overdentures assisted by a single implant that was positioned mesially to the maxillary sinus. The modified plaque index (MPI), modified gingival index (MGI), pocket depth (PD), implant stability (IS), and vertical bone loss (VBL) were measured at prosthesis delivery (T0), and 6 (T6) and 12 months (T12) after delivery. The oral health impact profile (OHIP-14) questionnaire was used to assess oral health-related quality of life (OHRQoL) at T12. Significant differences between observation times were performed using Friedman and Wilcoxon signed-rank tests for MPI and MGI and using repeated measures ANOVA with Bonferroni correction of P values for PD, IS, VBL, and OHIP. Between-group comparison of MPI and MGI the Mann-Whitney test was used, while for PD, IS, VBL, and OHIP comparison was made using independent samples t test (α=.05 for all tests). The implant survival rates were 100% for both groups. MPI and PD significantly increased with time for both groups. MGI significantly increased with time for the CSL group only (P=.049). The IS significantly decreased with time for the IOD group. VBL increased significantly from T6 to T12 for the CSL (P=.042) and the IOD (P=.002) groups. The CSL group recorded higher MPI, MGI, PD, and IS values than the IOD group (P<.05). The IOD group recorded higher VBL than the CSL group (P<.001). The CSL group scored significantly lower OHIP-14 values (better OHRQoL) than the IOD group for all values (P<.05). In comparison with implant-assisted partial overdentures, closed sinus lift with fixed prostheses had higher implant stability, reduced bone loss, and higher participant OHRQoL. However, peri-implant soft tissue health was found to be better with implant overdentures.

Evaluation of Surgical Outcomes of Zygomatic Implant-Supported Rehabilitation of Atrophic Maxillary Arches - A Prospective Study.

Prosthetic rehabilitation with implants in the atrophic edentulous maxilla often requires a bone augmentation procedure to enable implant placement and integration. However, rigid anchorage can also be achieved using long zygomatic implants. The aim of this study was to evaluate the surgical outcomes of rehabilitation of atrophic posterior maxillary ridges with zygomatic implants using the zygomatic success code (ZSC) and derive the success grade for the procedure based on the observed results. A total of eight implants were placed in an extrasinus technique based on the zygomatic anatomy-guided approach. The following were evaluated postoperatively - primary stability, maxillary sinus pathology, soft-tissue healing and prosthetic offset. The ZSC score was calculated, and success grading was given with ZSC based on Aparacio et al.,'s guidelines. One implant had Grade 1 mobility and partial maxillary sinus opacification, 25% (n = 2) revealed a mild recession exposing the implant head and 12.5% (n = 1) showed significant recession up to 7 mm. The prosthetic offset of zygomatic implants was scored -1 for all eight implants. Five implants were given a success code of 1/1/1/1 and a success grade of Grade I, two implants were given code 1/1/2/1 with Grade II and one implant 2/2/3/1 and grade III. The results imply that zygomatic implants can be a successful option in maxillary rehabilitation. The zygomatic implants, as a graft less and promising solution to the rehabilitation of atrophied maxillary arches, have excellent surgical outcomes with varied advantages.

Bicortical stability of implants placed in severely atrophic posterior maxilla: A case report

Maxillary sinus lift is a common procedure to achieve adequate alveolar bone height in patients with sinus hyper-pneumatization. Simultaneous implant placement with sinus floor augmentations is possible when appropriate primary stability could be achieved. In severe atrophic posterior maxillary ridge, vertical bone height is sometimes less than 4mm, which may hinder simultaneous implant placements and necessitate two stage procedure. In current study, a novel technique is described to perform a single stage implant placement with bicortical stability in severe atrophic maxilla that can shorten the treatment time of an edentulous patient. During the procedure, to achieve an adequate access a conventional lateral window osteotomy is performed. After elevating the Schneiderian membrane using conventional instruments, an autologous ramus block is harvested from the mandible and then the block will be fixed in correct location in the sinus using screws with appropriate length to build sufficient stability as superior cortex for simultaneous implant insertion.

Efficacy of simultaneous placement of dental implants in osteotome-mediated sinus floor elevation with and without bone augmentation: A systematic review and meta-analysis.

The aim of the present systematic review was to assess the effectiveness of simultaneous placement of implant in osteotome-mediated sinus floor elevation (OMSFE) procedure with and without bone augmentation. An exploration of randomized clinical trials (RCTs) was systematically done in three databases comprising PubMed, Cochrane, and Google Scholar complemented by a thorough manual search of periodontology/implantology-related journals. A final inclusion of 6 RCTs (2010-2020) was done to investigate the efficiency of simultaneous implant placement with OMSFE in conjunction with bone augmentation. A meta-analysis was further conducted with comparable studies which assisted in attaining a final conclusion regarding the survival rate, endosinus bone gain (ESBG), and marginal bone loss (MBL). Data synthesis was performed on the basis of 6 trials and further meta-analysis was performed to statistically validate the clinical and radiographic outcomes. Meta-analysis on the parameters indicated greater ESBG (mean difference [MD]: 0.82; [95% confidence interval [CI]: 0.72-0.91, P ≤ 0.0001]), which was also associated with minimal MBL (MD: -1.11; [95% CI: -1.53-0.68, P ≤ 0.0001)] in the bone augmentation group. However, the parameter of implant survival rate (risk ratio: 1.04; [95% CI: 0.83-1.31, P = 0.6849)] failed to reveal significant difference between the two groups. In the restoration of masticatory apparatus, simultaneous placement of implant in OMSFE with bone augmentation can be considered as successful and predictable treatment approach in deficient posterior maxillary ridges. It contributes toward bone neoformation resulting in greater ESBG as well as a substantial decrease in MBL.

Two-Step Progressive Transcrestal Sinus Augmentation Using a 4.5 mm Unloaded Implant as a "Temporary Implant" in Highly Atrophic Ridge: Case Report.

Severe atrophic posterior maxillary ridge (residual bone height < 3 mm) could be a challenging situation to place dental implants. Several treatment options have been proposed, but some of them may require advanced surgical skills to achieve best results. In this article, we present a novel and easier technique to allow implant placing in localized areas of severe atrophy. In a first step, a 4.5-length extra-short (unloaded) implant is placed after a transcrestal maxillary sinus floor augmentation (MSFA). After the gained apical bone consolidation, this "temporary implant" is atraumatically removed and a longer and wider definitive implant is placed to support the definitive single restoration. The case of a 45-year-old female treated with this approach is also presented. The patient suffered a severe resorption in the upper right molar area after a tooth extraction. Four months after the "temporary implant" placement and MSFA grafting with plasma rich in growth factors and autologous bone, 3 mm of dense apical bone gain could be observed. In a second surgical time, the 4.5 mm-length "temporary implant" was removed, and a 5.5 mm-length "definitive implant" was placed. This second implant was placed in a denser type 1 (1,000 Hounsfield Unit) new formed apical bone. Four months later, the implant was loaded with a screw-retained crown over a transepithelial (intermediate abutment). After 1-year follow-up, the implant was in health and no mechanical or biological complications were noticed. The satisfactory results of this case encourage the realization of new studies to elucidate its reproducibility.

Efficacy of platelet-rich fibrin in maxillary sinus augmentation and simultaneous implant placement in deficient maxillary ridges: A pilot comparative study

BackgroundRehabilitation with dental implants has become the most widely accepted treatment protocol for rehabilitation of lost natural teeth. Direct sinus lift is one of the most predictable procedures for augmenting the deficient posterior maxillary ridges. MethodsThe study was designed in patients with insufficient bone for implants in the maxillary posterior ridges. The test group received platelet-rich fibrin alone as filler, and the control group received a bone allograft. The residual bone height (RBH), implant mobility, and soft tissue characteristics between and within the groups were compared and analyzed. ResultsBoth the groups had considerable gain in RBH, and the intragroup analysis revealed clinical gain in bone height in both the groups, with the test group exhibiting statistically significant gain which kept on improving from 6 months with z= -3.477 and a p value of 0.001 to 9 months with z=-3.531 and a p value of 0.027. ConclusionThe results suggest that the use of platelet-rich fibrin alone improves the bone regeneration, thereby achieving predictable and stable augmentation of the sinus floor required for the success of implant therapy.

A three-in-one alveolar process reconstruction protocol for maxillary molar sites with severe residual bone height deficiency: A proof-of-concept pilot study.

Implant placement in maxillary molar sites with severe height deficiency often requires multiple surgeries, which was time-consuming, invasive, and subject to serious postoperative complications. To introduce and assess a three-in-one technique (extraction, alveolar ridge preservation [ARP], and sinus elevation) for augmenting deficiency maxillary molar alveolar ridges. Fourteen patients with severe posterior maxillary ridge height deficiency underwent extraction, sinus elevation via an intrasocket window and ARP using sticky bone and then covered with acellular dermal matrix (ADM). Primary closure was intentionally not obtained. Cone-beam computed tomography and periapical radiography were used to measure dimensional ridge changes over time. Bone biopsies were taken at implant placement 7-21 months after surgery, which proceeded without additional grafting. Peri-implant soft tissue was assessed after 8-12 months of functional loading. Maxillary molar sites (13 first molars, 1 second molar) with a mean sinus floor height of 1.73 ± 0.86 mm and mean buccal plate thickness of 1.62 ± 1.15 mm were elevated and grafted. Immediately after surgery, the mean sinus floor height was 14.03 ± 1.97 mm and the alveolar thickness at virtual implant platform level was 12.99 ± 1.88 mm. After 5-9 months healing, those measurements decreased by 2.45 ± 1.73 mm (p= 0.000) and 3.88 ± 3.95 mm (p= 0.006), respectively. Healed ridges were composed of 18.74% ± 4.34% mean vital bone and 19.08% ± 9.10% mean residual graft. After 8-12 months of functional loading, the peri-implant tissue appeared healthy, and there was a mean marginal bone loss of 0.12 ± 0.11 mm. For maxillary first molar sites with severe sinus floor height deficiency, this minimally invasive three-in-one treatment allows for uncomplicated implant placement and short-term functional stability.

Posterior maxillary ridge augmentation with sinus lift using Mineralized Plasmatic Matrix versus Autogenous Bone Graft

The purpose of this study was to investigate the effect of posterior maxillary ridge augmentation using mineralized plasmatic matrix versus autogenous bone graft on implant body stability in a randomized clinical trial. Twenty implants were placed in eight sinuses with a defective edentulous posterior maxillary ridge. After diagnosis of each case clinically and radio graphically, patients were randomly assigned into two equal groups of 3 patients each. After implant placement, the ridges assigned to the study group received MPM – prepared by centrifugation of patient’s blood- mixed with autogenous bone graft; while ridges in the control group received the gold standard of particulate autogenous bone graft. Implant stability was assessed in ISQ unit by Osstell, and Vertical bone height was assessed by CBCT at 4, 9 months. All demographic data and ISQ scores and CBCT measurements were collected and statistically analyzed. Results showed that, there was a statistically significant increase in implant stability, and vertical bone height after 4 months in both groups (P 0.05). The mean Osstell gain, bone height in the study group was significantly higher than those in the control group (P < 0.05).

Bone Formation After Maxillary Sinus Floor Elevation Using Titanium Mesh Versus Titanium Screws Without Any Graft Material: A Preliminary Study

Aim: The purpose of the present study is to evaluate the bone volume and quality formed following graftless maxillary sinus lifting through lateral window approach to compare the efficiency of the use of titanium screws versus the use of titanium mesh in preserving the space below the uplifted maxillary sinus membrane allowing for stable blood clot formation in severly atrophied posterior maxillary ridge. Subjects and Methods: The current study include 10 maxillary sinuses, The study patients were partially or completely edentulous in the posterior maxilla and required unilateral or bilateral maxillary sinus augmentation. All patients were selected from the out-patient clinic of Oral and Maxillofacial Surgery Department, faculty of oral and dental medicine, Cairo University. Results: The sinuses were divided into two equal groups (study and control groups), both groups underwent maxillary sinus lift procedures using either space-maintaining titanium screws for the study group or space-maintaining titanium mesh for the control group. The study was a double blind one (participants and outcome assessors were blinded throughout the study). Conclusion: application of titanium mish with micro screws to support the sinus membrane was easier clinically than using long titanium screws alone, as the accessibility and direction of drilling was more difficult when long titanium screws were used

THE EFFECT OF OSSEODENSIFICATION TECHNIQUE ON IMPLANT STABILITY (CLINICAL TRIAL)

Introduction: Dental implants primary or initial stability originates from the engagement with the cortical bone mechanically, whereas the secondary stability signifies the stability biologically by means of osseointegration through the bone formation and remodeling from the cancellous bone. Osseodensification is an innovative biomechanical technique to prepare the site. It uses Densifying Burs to produce low plastic deformation owing to its non-removal densifying method of site preparation, which preserves the bone enhancing the host site. Objectives: To evaluate the osseodensification (OD) technique used in implant site preparation by using the newly designed burs (Densah burs), and its effect on enhancing implant primary and secondary stability. Material and Methods: Twenty dental implants were placed in ten patients; each patient received one implant using the new Osseodensification drilling technique and one implant using the conventional drilling technique in the posterior maxillary ridge. Osstell was used in measuring resonance frequency (ISQ-scale) which is used to determine the amount of implant stability. Results: The results showed a significant improvement in both primary and secondary stability using densah burs. Conclusions: Densah burs produce better bone quality around the implant than conventional drills, and therefore, there is an improvement in the primary and secondary stability.

Classification of Sinus Membrane Perforations Occurring During Transcrestal Sinus Floor Elevation and Related Treatment.

The predictability of transcrestal sinus floor elevation (tSFE) in elevating the sinus membrane following posterior maxillary ridge resorption has been widely demonstrated. To minimize complications and increase success, a literature search was conducted to validate procedures used for tSFE. A decision tree based upon timing of perforations was then developed to improve membrane-perforation management during the procedure. At each surgical procedure, the clinician is encouraged to use size of the perforation, time during the procedure in which the perforation occurred, and resulting symptoms to determine the best treatment approach. This article discusses all possible sinus membrane perforations based on timing of that surgical procedure, allowing the clinician to recognize and successfully rectify this clinical complication while successfully completing the surgery. With this aim, a classification of sinus membrane perforations occurring during tSFE is proposed, simultaneously providing guidelines to effectively manage these complications.

Maxillary Ridge Vertical Augmentation Based on a Mixture of Xenogenic and Allogenic Bone Supported by Resorbable Membrane: One Case Report

One 60 years-old patient was scheduled for left posterior maxillary ridge augmentation due to failure of standard implants, followed by successful maxillary dental implants. We used an unproved technique consisting in a mixture of 50% allogenic and 50% xenogenic bone supported by reabsorbable membrane. No complications were found at the different stages of the treatment, and at the ending the patient showed a good level of satisfactory outcomes. Radiological evaluation demonstrated ridge augmentation able to support implant, and within the graft islands of connective and bone-like tissue was found. Within these tissues osteoclasts and osteoblast putative cells were found. Results demonstrate that the used method in addition to support implants has osteogenic and bone remodeling activity.

Five-year Radiographic Changes of Residual Ridges under Maxillary Complete Denture and its Opposing Mandibular Two Implant-Retained Overdenture with Different Resilient Attachments

Aim: This study aimed to radiographically compare the effect of different resilient attachments on maxillary and mandibular residual ridge changes after 5 years of using mandibular 2-implant retained overdentures. Materials and methods: Eighteen completely edentulous male patients, with age ranging from 45 to 60 years, were included in the study. Maxillary complete dentures were constructed opposed to 2-implant retained mandibular overdentures. Patients were divided randomly into three equal groups according to type of attachment into; ball/socket (BOD) group, Locator attachment (LOD) group, and positioner attachment (POD) group. Maxillary and mandibular ridge resorption were determined by using the proportional area index method on the panoramic radiograph taken at time of overdenture insertion and at five years later.Results: The minimal rate of ridge resorption was recorded for posterior maxillary ridges (Max-PRRR) followed by that of posterior mandibular ones (Mand-PRRR), while the highest resorption rate was recorded for anterior maxillary ridges (Max-ARRR). The study did not reveal significant difference in ridge resorpion between the resilient attachment systems.Conclusion: Mandibular overdentures retained by two implants with the described attachment systems provide a similar and acceptable range of residual ridge resorption (RRR) after 5years of function. The reduced RRR with Locator attachments proved its ability to provide an equitable load on the implants and tissue bearing areas during function.

Antral Balloon Sinus Elevation and Grafting Prior to Dental Implant Placement: Review of 34 Cases

The objective of this study was to assess the antral balloon technique for sinus elevation followed by bone graft and implant placement. A total of 34 patients with atrophic edentulous posterior maxillary ridges underwent antral balloon sinus elevation followed by bone grafting (autogenous bone retrieved from the chin mixed with platelet-rich plasma) and implant placement. The population consisted of 26 male and 8 female patients with a mean age of 42 years (range, 33 to 56 years). Successful sinus membrane balloon elevation was performed in all 34 patients, and 62 implants were placed. A membrane tear in one patient was managed intraoperatively by placement of a collagen membrane. Two implants failed within 6 months, and the survival rate of the other 60 implants was 100% after 3 years of follow-up. The mean inflated balloon volume was 1.96 mL and the mean elevated sinus height by balloon was 11.6 mm. An average bone gain of 7.5 mm (range, 5.2 to 10.5 mm) was observed. This case series demonstrates the feasibility of antral balloon sinus membrane elevation followed by bone augmentation and implant placement. This technique offers optimal assurance for membrane safety, and it is less invasive than the routine lateral window technique, safe, and associated with less postoperative bleeding and discomfort. This method is predictable, easy to learn, and associated with low complication rates. However, large comparative studies with other techniques are required.

Simultaneous management of unfavorable posterior intermaxillary space and vertical ridge deficiency

After extraction of posterior mandibular teeth the posterior dentoalveolar maxillary extrusion is common finding in edentulous patients, in this conditions if the posterior maxillary teeth were lost the initial decrease in bone width is due to the resorption of the buccal bone plate. As the edentulous area continues to atrophy, there is a continuing loss of bone height and density and an increase in antral pneumatization. According to the type of ridge deficiency, various techniques can be used for correction of this condition. A particulate and block autogenous bone has been used for correction of alveolar ridge deficiency. This article presents an innovative technique that can be used to correct moderate to severe localized defects of the alveolar process prior to implant placement in posterior maxillary ridge.

Resonance frequency analysis of stability on ITI implants with osteotome sinus floor elevation technique without grafting: a 5‐month prospective study

The aim of the present study was to (1) monitor the stability changes of ITI implants placed in atrophic posterior maxillary ridges with osteotome sinus floor elevation (OSFE) without grafting during the first 5 months of healing utilizing resonance frequency analysis (RFA) and (2) determine the factors that affect the implant stability quotient (ISQ) at placement and healings. Forty-two ITI implants were placed in the posterior maxilla in 32 patients with OSFE without bone grafting. The residual vertical bone height ranged from 4 to 8 mm (average 6.36 mm). Bone type was classified into one to four groups according to the Lekholm and Zarb index. ISQ was tested on the day of surgery and consecutively at 2, 4, 6, 8, 12, 16, and 20 weeks by RFA. The 40 osseointegrated implants represented a survival rate of 95.2%. All the 40 implants achieved good primary stability and reached a comparably high stability at 16 weeks postoperation with a dip between 2 and 6 weeks in the stability curve. There was no significant difference of ISQ between type3 and type4 bone at implant placement and follow-up. The mean ISQ and its changing pattern did not demonstrate a statistically significant difference according to the pretreatment vertical bone height and implant length. The findings of this study indicated that uneventful osseointegration may be predictable applying OSFE alone with no grafting in atrophic posterior maxilla. Residual bone height (RBH), implant length, and bone type did not seem to affect the implant stability in this clinical situation.

Maxillary bone resorption in patients with mandibular implant-supported overdentures or fixed prostheses

For several years, implant-supported overdentures have been used with excellent results in rehabilitation of the edentulous mandible. The effect on the antagonistic jaw bone resorption however, has not yet been evaluated. The aim of this study was to examine on orthopantomograms the anterior and posterior maxillary ridge resorption in three groups of patients with different mandibular prosthetic reconstructions: (1) overdentures supported by two implants, (2) fixed prostheses supported by four to six implants, and (3) complete dentures. The results indicated a more pronounced annual bone resorption in complete denture wearers compared to patients with implant-supported overdentures. A limited but continuing bone resorption was observed for the patients with implant-supported overdentures, and a slightly higher annual bone resorption occurred in the implant-supported fixed prosthesis group.

Extraosseous Chondrosarcoma of the Maxilla

STATED succinctly, cartilaginous neoplasms of the maxilla are uncommon, chondrosarcoma is rare, and an extraosseous chondrosarcoma in this location is apparently unique. Report of a Case A 37-year-old white man was admitted to the Cedars of Lebanon Hospital on Jan 17, 1967. He had been in satisfactory health until three months prior to admission when he noted the presence of a painless gingival swelling along the lingual aspect of the posterior maxillary ridge adjacent to the second molar tooth. Gradual asymptomatic enlargement occurred and two weeks prior to admission extraction of the second molar tooth and biopsy of the lesion were done; a diagnosis of chondrosarcoma was rendered. Roentgenologic examination disclosed no abnormalities of the bony maxilla. Physical examination revealed an elevated, ovoid, firm, nontender mass, 1 cm in diameter, on the lingual aspect of the left maxillary alveolus adjacent to the socket of the recently extracted tooth. The tumor