Alveolar Preservation Research Articles

Volumetric Evaluation of Alveolar Ridge Preservation Using Dense PTFE (d-PTFE) Membranes Intentionally Exposed to the Oral Cavity After Immediate Implant Placement—A Retrospective Study

Background: Tooth loss causes alveolar bone resorption, which may hinder the ability of implant placement. Socket preservation with immediate implant placement is one of the methods used to reduce bone resorption. In this retrospective study, we evaluated the influence of the use of dense polytetrafluoroethylene (d-PTFE) membranes on alveolar preservation after tooth extraction and with the installation of immediate dental implants. Methods: In this retrospective study, one hundred and four patients were divided into two groups: immediate implant and gap filling with heterogenous bone graft (control group, 52 patients) or immediate implant, gap filling with heterogenous bone graft, and covering with a d-PTFE membrane with dimensions of 12 × 24 mm, which was intentionally left exposed to the oral cavity (test group, 52 patients). Tomographic data were obtained before and 12 months after the surgical procedures. Results: The membranes exposed in the oral cavity showed no infection. Volumetric analyses revealed a statistically significant difference in alveolar ridge resorption for the control and d-PTFE groups, 16.75% and 4.55%, respectively. Conclusions: Intentionally exposed d-PTFE membranes showed minimal complications. Based on the volumetric results, alveolar ridge preservation with d-PTFE membranes was superior to the bone graft alone in immediate implant placement.

Impact of photobiomodulation in alveolar ridge preservation and implant stability after a dental extraction: a systematic review.

The bone volume preservation after dental extraction is challenging in case of implant rehabilitation for functional and aesthetics results. Photobiomodulation (or LLLT) is used in medicine for its properties of accelerating the healing process. The aim of the systematic review was to determine if the use of photobiomodulation had an impact on implant stability and on alveolar bone healing, either in quality or in quantity. A systematic review following the PRISMA guidelines was conducted on the databases PubMed, Science Direct, Scopus and Google Scholar. The review was registered on Prospero under the number CRD42023467581. 414 articles were screened, of which 12 were selected for the review. In 10 of the 12 articles, LLLT seemed to show a positive impact on bone healing and implant stability. Regarding alveolar preservation, 6 out of 8 studies found statistically significant results. Regarding implant stability, 3 out of the 4 articles found a statistically significant impact of photobiomodulation versus control group. Despite the great heterogeneity of the studies, some LLLT protocols seemed consensual: the use of a Ga-Al-As laser with an emission over 800nm with a continuous emission consisting of 3 to 4 sessions each with a duration of 4 to 5min, on a sole application point. The use of photobiomodulation seemed to inhance the alveolar bone healing after a dental extraction, and the implant stability in case of immediate extraction-implantation. Further randomized controlled trials with a placebo group seem mandatory to corroborate the results.

Tomographic and Electron Microscopy Description of Two Bone-Substitute Xenografts for the Preservation of Dental Alveoli.

After tooth extraction, bone levels in the alveoli decrease. Using a bone substitute can help minimize this bone loss. The substitute can be sourced from a human or animal donor or synthetically prepared. In this study, we aimed to address the following PICOS question: In patients needing dental alveolar preservation for implant placement, how does alveolar preservation using a bovine hydroxyapatite bone xenograft with collagen compare to a xenograft without collagen in terms of changes in alveolar height and width, bone density, and the characteristics of the bone tissue observed in biopsies taken at 6 months? We evaluated two xenograft-type bone substitutes for preserving post-extraction dental sockets using tomography and microscopy to answer that question. A total of 18 dental alveoli were studied: 11 preserved with a xenograft composed of apatite (InterOss) and 7 with a xenograft composed of apatite-collagen (InterOss Collagen). Tomographic controls were performed at 1 and 6 months, and microscopic studies were performed on 13 samples. The biopsies were examined with scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). A Multivariate Analysis of Variance (MANOVA) was conducted in the statistical analysis, revealing a significant increase in bone density over time (p = 0.04). Specifically, bone density increased from an average of 526.14 HU at 30 days to 721.96 HU at 60 days in collagen-free samples. However, no statistically significant differences in height or width were found between groups. The MANOVA results indicated that the overall model had a low predictive ability for height, width, and density variables (R-squared values were low), likely due to sample size limitations and the complexity of bone tissue dynamics. On the other hand, FTIR analysis revealed the presence of phosphate groups, carbonates, and amides I, II, and III, indicative of inorganic (hydroxyapatite) and organic (type I collagen) materials in the xenografts. TGA and DSC showed high thermal stability, with minimal mass loss below 150 °C. Finally, both xenografts were influential in alveolar bone regeneration after extraction without significant differences. The trend of increasing collagen density suggests an effect that requires further investigation. However, it is recommended that the sample size be increased to enhance the validity of the results.

Use of autologous tooth-derived material as a graft in the post-extraction socket. Split-mouth study with radiological and histological analysis

BackgroundThe healing process after tooth removal involves bone remodelling which implies some loss of alveolar bone volume. Among materials proposed for minimising this remodelling and preserving the bone, autologous dental tissue is a promising option, but more data are needed. In this context, we evaluated size and density changes using cone beam computed tomography in autologous dental material (ADM)-preserved sockets compared to controls, and assessed biological responses by histological analysis.MethodsA split-mouth study was conducted including 22 patients, who underwent removal of ≥ 2 single-rooted teeth with intact sockets, assigning one socket to the experimental group which received ADM for alveolar preservation and another to the control group, which only underwent blood clot stabilisation. Cone beam computed tomography was performed postoperatively (week 0) and at weeks 8 and 16 to assess socket size and bone density. Histological analysis was carried out on trephine biopsies taken (Ø4 × 4.5 mm) from the experimental group.ResultsLess horizontal shrinkage was observed in the ADM group, especially at week 16 considering the group-by-time interaction for the following variables: difference in height between the lingual and buccal alveolar crests (-1.00; p < .01; 95% CI: -0.28 – -1.73), and half-widths, measured as the distance from the long axis of the missing tooth to the buccal alveolar crest at 1 mm (-0.61; p < .01; 95% CI: -0.18 – -1.04) and at 3 mm (-0.56; p < .01; 95% CI: -0.15 – -0.97) below the crest, with mean decreases of 1.07 and 2.14 mm in height difference, 0.66 and 1.32 mm in half-width at 1 mm and 0.43 and 1.02 mm in half-width at 3 mm in ADM and control groups respectively. Densitometry analysis showed higher bone densities in Hounsfield units in the ADM group considering all factors analysed regardless of time point and socket third (coronal, middle, or apical). Histologically, there were no signs of inflammation or foreign body reaction, and dentin particles were surrounded by and in close contact with bone tissue.ConclusionThese results add to the evidence that dentin can be used successfully as a material for alveolar socket preservation, given its desirable mechanical and biological properties, and warrant larger studies.

Guided Bone Regeneration for the Treatment of Peri-Implantitis: Clinical Case Report

Periodontal disease is characterized as an inflammatory process that damages the periodontal lining and/or support tissues. Peri-implantitis is among the periodontal alterations, being caused by bacterial biofilm causing loss of underlying bone insertion, leading to modifications in its architecture that form intraosseous defects of various types. For the treatment of peri-implantitis there are non-surgical, surgical, resective, regenerative, combined techniques and the decision-making will depend on the degree of the bone defect. Therefore, guided bone regeneration (GBR) is an efficient and simple technique for bone augmentation, which is widely used to restructure bone defects that occur in the alveolar ridge and in the peri-implant region. Biomaterials are alternatives to be used in guided bone regeneration due to their excellent biocompatibility, osteoinductive properties, low degradation rate and their hydrophilicity, which collaborates with the absorption of blood cells and proteins that will help in osseointegration. Female, 58-year-old normosistemic patient, attended a private dental office complaining of pain, bad smell, bleeding and bad taste in the peri-implant region referring to element 25, on its distal face to the mesial face of the element tooth 26. After imaging exams, periodontal probing and the patient's past history, extraction of element 26 was performed, decontamination protocol of the implant surface of 25 through mechanical, chemical and physical means performing antimicrobial photodynamic therapy and finally, a guided bone regeneration was performed, using the allogeneic bone grafting technique associated with a polytetrafluoroethylene membrane in its expanded form (e-PTFE) for recovery of the bone defect and alveolar preservation. Thus, guided bone regeneration has shown high success rates and greater predictability when well indicated and performed, making it important for the maintenance of periodontal and peri-implant health.

Changes of the Alveolar Bone Ridge Using Bone Mineral Grafts and Collagen Membranes after Tooth Extraction: A Systematic Review and Meta-Analysis.

Alveolar preservation techniques for esthetic or functional purposes, or both, are a frequently used alternative for the treatment of post-extraction sockets, the aim of which is the regeneration of the lesion and the preservation of the alveolar bone crest. Studies published in PubMed (Medline), Web of Science, Embase, and Cochrane Library databases up to January 2024 were consulted. Inclusion criteria were established as intervention studies, according to the PICOs strategy: adult subjects undergoing dental extractions (participants), with alveoli treated with bone mineral grafts and collagen membranes (intervention), compared to spontaneous healing (comparison), and observing the response to treatment in clinical and radiological measures of the alveolar bone crest (outcomes). We obtained 561 results and selected 12 studies. Risk of bias was assessed using the Cochrane Risk of Bias Tool, and methodological quality was assessed using the Joanna Briggs Institute. Due to the high heterogeneity of the studies (I2 > 75%), a random-effects meta-analysis was used. Despite the trend, no statistical significance (p > 0.05) was found in the experimental groups. The use of bone mineral grafts in combination with resorbable collagen barriers provides greater preservation of the alveolar ridge, although more clinical studies are needed.

Aplikimi i plazmës së pasur me fibrinë të gjeneratës së dytë (PRF) tek ekstraksionet multiple

Tooth extraction is a common oral surgical procedure in dental practice. Indications for this procedure include extensive caries, trauma, inflammatory processes, cystic and tumorous formations, as well as orthodontic and pros- thetic needs of the patient. The development of implant technology and aesthetic dentistry has necessitated the preservation or creation of a biological base after tooth ex- traction. Alveolar preservation has been recommended as an effective, economical, and simple method to maintain the contours of the bone base. For this purpose, a variety of materials and techniques are used, including autografts, allografts, xenografts, and alloplastic materials, which offer osteogenic, osteoinductive, and osteoconductive abilities. An improved method of obtaining platelet-rich fibrin (PRF) was presented by Dr. Choukroun in 2001, offering a simple and more effective alternative compared to previous tech- niques. In this case report, a 42-year-old patient underwent multiple tooth extractions with alveolar preservation using PRF. After the application of the PRF protocol, the clinical width of the alveolus was evaluated, and clinical parame- ters were monitored for 3 months. The results indicate that the use of PRF for alveolar preservation provides an effec- tive and safe method for promoting wound healing and bone regeneration after tooth extraction. Furthermore, the study’s conclusions confirm that PRF is a valuable therapeu- tic material for alveolar preservation after tooth extraction and suggest that this method may yield optimal clinical outcomes for patients.

Comprehensive clinical and histological evaluation of bovine hydroxyapatite bone graft with polypropylene membrane versus leukocyte- and platelet-rich fibrin for alveolar preservation after tooth extraction.

Osseointegrated implant placement in the ideal prosthetic position necessitates a sufficient residual alveolar ridge. Tooth extraction and the subsequent healing process often lead to bony deformities, characterized by a reduction in alveolar ridge height and width, resulting in unfavorable ridge architecture for dental implant placement. Several materials, including allografts, alloplastics, xenografts, and autogenous bone, are commonly used to address these concerns. In this context, leucocyte- and platelet-rich fibrin (L-PRF) emerges as a promising solution. This case report aims to compare the clinical and histological efficacy of bovine hydroxyapatite bone graft covered with polypropylene membrane (BHAG-PM) and leucocyte- and platelet-rich fibrin (L-PRF) in preserving dental alveoli following tooth extraction. Extraction, graft placement in the alveoli, and the anterior border between extracted elements were performed for both treatment groups. Up to 24 months of follow-up revealed satisfactory and comparable clinical and histological outcomes. These results suggest that both BHAG-PM and L-PRF effectively promote alveolar preservation, paving the way for ideal implant placement. In general, bone-substitute materials are effective in reducing alveolar changes after tooth extraction. Xenograft materials should be considered as among the best of the available grafting materials for alveolar preservation after tooth extraction. Both techniques effectively preserve the alveolar bone and facilitate the placement of osseointegrated implants in ideal positions, paving the way for successful oral rehabilitation.

Histomorphometric Evaluation of New Bone Formation, Dimensional Changes, and Residual Particles in Alveolar Ridge Preservation Techniques Using InterOss® Anorganic Cancellous Bone Graft: A Longitudinal Study.

We worked on 14 single-root or premolar teeth with fused roots with an indication for the preservation of the alveolar ridge and the subsequent placement of a dental implant. The techniques performed in the study were the Bartee technique for the preservation of the alveolar crest in seven teeth that presented a good amount of the remaining bone tissue (minimum 4 mm in the apical-coronal direction) or that had a buccal or lingual/palatine wall defect (group A) and the Bio-Col alveolar preservation technique (group B), in seven teeth that presented an intact alveolus (four remaining walls). Xenograft was used in both groups. Results: Morphometric evaluation of group A (Bartee technique) and group B (Bio-Col technique) showed 11.48% and 13.24% of reabsorption in the vertical direction (p=0.482) and 21.95% and 20.55% in the horizontal direction, respectively (p=0.949). At 6 months of healing, the histomorphometric evaluation showed 31.10% new bone formation and 28.09% residual particles in group A, 13.24% new bone formation (p=0.744), and 20.55% residual particles for group B (p=0.302). There were no statistically significant differences in dimensional changes between both groups. The Bartee and Bio-Col alveolar ridge preservation technique combined with a xenograft provides dimensional stability, counteracting the physiological resorption process and ensuring the stability of the surrounding tissues. Therefore, both techniques represent a predictable option for dental implant placement at 6 months of healing.

Preservation of Socket for Immediate Dental Implants in Aesthetic Zone from Upper Jaw: Aesthetic Approach-Case Report

Ensuring optimal aesthetic outcomes in dental implant cases within the maxillary anterior area requires careful consideration of socket preservation and atraumatic tooth extraction. These factors play a crucial role in achieving successful and aesthetically pleasing treatments. The objective of this study is to present a series of clinical cases involving dental extractions of anterior maxillary teeth with a poor prognosis. This study highlights the importance of socket preservation and atraumatic tooth extraction in ensuring optimal aesthetic results in dental implant cases within the maxillary anterior area. In these cases, a two-armed lever technique was planned for atraumatic alveolar preservation during the extraction process.Following the tooth extraction, the fresh socket was reclassified, and dental implants were subsequently placed using a modified drilling technique in certain cases. The authors assessed the primary stability of the implants, while in other cases, bone regeneration procedures were performed. The presented clinical cases demonstrate the successful implementation of the two-armed lever technique for atraumatic alveolar preservation, leading to favorable outcomes in terms of primary implant stability and bone preservation. Techniques for bone preservation after tooth extraction aim to minimize post-extraction bone resorption. By implementing appropriate protocols, such as the concept of the dual zone and the two-armed lever technique, successful outcomes can be achieved in terms of both aesthetics and preservation of the alveolar bone.

Comparison between immediate implant techniques and delayed implants using different Alveolar Preservation techniques on functional and aesthetic aspects: Literature review

Comparison between immediate implant techniques and delayed implants using different Alveolar Preservation techniques on functional and aesthetic aspects: Literature review

Comparative analysis of alveolar preservation using leukocyte-platelet rich fibrin during maxillary canine distalization: A retrospective study

Objective: This study evaluated alveolar preservation using leukocyte-platelet rich fibrin (L-PRF) in adult patients, comparing it to control alveoli. Methods: Conducted from 2016 to 2018, the study included 17 adult patients, aged between 20 and 45 years, diagnosed with either Class I or Angle Class II-1 malocclusion. Participants underwent first premolar extractions, with L-PRF treatment applied to one side of their mouth, while the other side served as a control. This retrospective study compared tomography data from these patients, who also underwent maxillary canine retraction. One side of the mouth was treated as an experimental alveolus, preserved with L-PRF, and the other as a control. Data normality was assessed using the Shapiro-Wilk test. The Wilcoxon test was used for group comparisons, and the McNemar test was applied to fenestrations. Results: No statistically significant differences were observed in root length changes and surrounding bone tissue between the two sides (P &gt; 0.05). Conclusion: The study found no significant differences in root length reduction and changes in supporting bone tissue between the experimental and control sides. This suggests that alveolar preservation with L-PRF does not alleviate the deleterious effects observed during maxillary canine distalization.

Efficacy of autologous platelet concentrate products for alveolar preservation: A meta-analysis.

The purpose of the study was to systematically evaluate the efficacy of autologous platelet concentrate products in the preservation of the alveolar ridge after tooth extraction through meta-analysis and provide a theoretical basis for the clinical application of autologous platelet concentrates to reduce alveolar bone resorption. This study conducted a meta-analysis of clinical trials between 2013 and 2023, focusing on autologous platelet concentrate products (e.g., PRP, PRF, CGF, and PRCF) used for alveolar ridge preservation after tooth extraction. The analysis included 122 articles and 371 extraction sockets. All statistical analyses were performed using Review Manager version 5.4. Results indicate that these platelet concentrates effectively reduced changes in horizontal width 1 mm below the alveolar crest and vertical socket height. They also promoted a higher percentage of new bone formation in extraction sockets compared with control groups. However, they did not significantly prevent horizontal bone resorption at 3 and 5 mm below the alveolar crest. In conclusion, autologous platelet concentrates are useful for alveolar ridge preservation, but larger clinical studies are needed to confirm these findings due to the relatively small sample size in this study.

Terapias de extração parcial (TEP): uma revisão da literatura

ABSTRACT One of the most common dental procedures is tooth extraction; however, the bone defect resulting from the process is only partially restored, leading to considerable bone loss. To rehabilitate a fully or partially edentulous patient, we must handle these sites with delicate surgical procedures. There is a large literature presenting attempts to overcome the negative effects of a dental extraction, with the aim of reducing tissue volume loss or restoring the alveolar architecture. In this context, Partial Extraction Therapy (PET) represents a subgroup of interventions to prevent bone loss after extraction using the tooth itself to prevent alveolar bone loss. This literature review aims to make a survey of the published articles on PET, with an emphasis on socket shield technique, and to explain the other techniques such as root burial, pontic-shield and proximal socket-shield, their indications and counter indications in order to deepen the knowledge of these techniques. To identify the included or considered studies, we adopted a detailed search strategy for MEDLINE and Cochrane Library focused in the last 31 years, whose language was English, Spanish or Portuguese. This text presents an analysis of current data regarding the alternatives for alveolar preservation and the installation of immediate implants in these areas, presenting the possibility of a different surgical technique. However, due to the immaturity and lack of conclusive scientific evidence regarding the predictability of the procedures, it is considered that the use of the socket shield technique must be done in an extremely cautious way.

Alveolar ridge preservation for further rehabilitation with implants: case report

SUB-HEADING: Alveolar ridge preservation is done when immediate or early implant placement is not indicated. PURPOSE: Report a case of extraction of the maxillary premolar, followed by alveolar preservation and later rehabilitation with implants. CASE REPORT: A 52-year-old male patient sought care for the rehabilitation of upper left second premolar tooth, which had a longitudinal fracture. The radiographic examination revealed the proximity of the root apex to the floor of the maxillary sinus and alveolar preservation was chosen. CONCLUSION: The clinical decision-making process for preservation starts before extraction.

Efficacy of the application of leukocyte and platelet-rich fibrin (L-PRF) on alveolar ridge preservation. A randomized controlled clinical trial.

Alveolar ridge preservation (ARP) is a well-defined treatment performed to reduce bone dimensional changes occurring during the healing of post-extraction sockets to allow for adequate implant placement. Leukocyte and platelet-rich fibrin (L-PRF) has been showing to potentially promote bone and tissue regeneration during wound healing. Therefore, the aim of this study is to evaluate its efficacy for ARP when applied to fresh extraction sockets, in comparison with spontaneous healing. Twenty-seven patients with hopeless non-molar teeth were treated. After randomization, fresh extraction sockets were either filled with L-PRF or allowed to heal spontaneously. CBCTs and intraoral scans were obtained immediately after extraction and at 4 months. Through superimposition of the obtained images, changes in the horizontal ridge width, height, buccal volume, and ridge contour changes were measured, as well as patient-reported outcome measures (PROM's). The ridge dimensions changed similarly in both groups. Although less reduction occurred in the test group at 1 mm from the bone crest, differences were not statistically significant (p > 0.05). Application of L-PRF did not prevent reductions of ridge contours, neither in the linear vertical aspect nor in volumetric changes. There were no differences between groups in the need for bone regeneration when placing implants. Patients in both groups reported similar outcomes in terms of bleeding, pain, inflammation, and function at 1 and 4 weeks postoperatively. Alveolar preservation with L-PRF neither minimized bone resorption occurring after tooth extraction in non-molar sites nor reduced the need for bone regeneration when placing implants. Furthermore, its use did not improve PROM's.

Randomized clinical study of injectable dextrin-based hydrogel as a carrier of a synthetic bone substitute

ObjectivesThis study aimed to improve the performance and mode of administration of a glass-reinforced hydroxyapatite synthetic bone substitute, Bonelike by Biosckin® (BL®), by association with a dextrin-based hydrogel, DEXGEL, to achieve an injectable and moldable device named DEXGEL Bone.MethodsTwelve participants requiring pre-molar tooth extraction and implant placement were enrolled in this study. BL® granules (250–500 µm) were administered to 6 randomized participants whereas the other 6 received DEXGEL Bone. After 6 months, a bone biopsy of the grafted area was collected for histological and histomorphometric evaluation, prior to implant placement. The performance of DEXGEL Bone and BL® treatments on alveolar preservation were further analyzed by computed tomography and Hounsfield density analysis. Primary implant stability was analyzed by implant stability coefficient technique.ResultsThe healing of defects was free of any local or systemic complications. Both treatments showed good osseointegration with no signs of adverse reaction. DEXGEL Bone exhibited increased granule resorption (p = 0.029) accompanied by a tendency for more new bone ingrowth (although not statistically significant) compared to the BL® group. The addition of DEXGEL to BL® granules did not compromise bone volume or density, being even beneficial for implant primary stability (p = 0.017).ConclusionsThe hydrogel-reinforced biomaterial exhibited an easier handling, a better defect filling, and benefits in implant stability.Clinical relevanceThis study validates DEXGEL Bone safety and performance as an injectable carrier of granular bone substitutes for alveolar ridge preservation.Trial registrationEuropean Databank on Medical Devices (EUDAMED) No. CIV-PT-18–01-02,705; Registo Nacional de Estudos Clínicos, RNEC, No. 30122.

Changes in Alveolar Bone Width Following Immediate Implant and Fresh Socket Preservation with Xenogeneic Gap-Filling Material Versus Guided Tissue Healing with Anatomical Tooth-Shaped Caps: A 3-Year Retrospective Case-Control Study.

This study aimed to calculate the 3-year dimensional change in crestal bone width when dental implants placed in postextraction sockets underwent two alternative techniques for alveolar preservation. Fresh sockets that had undergone immediate implant placement were categorized into one of two groups depending on the procedure type. For the xenogeneic biomaterial grafted (BG) group, the gaps between the metallic implant surfaces and the bony walls were filled with corticocancellous porcine bone; in the anatomical cap group, in which patients were treated with guided tissue healing (GTH), cross-linkable acrylic resin caps were immediately screwed on the implants. Absolute measurements of the alveolar width were performed on 3D images acquired before tooth extraction (thereby ensuring correct surgical treatment) and 3 years after surgery. Nonparametric statistics were performed, with the level of significance set at 1%. The results of 46 implants (placed in 36 patients) were analyzed, and 100% survival rates were reported for both groups at 3 years postsurgery. Minor swelling of treated areas was observed the first few days of healing, but neither mucositides, dehiscence events, nor suppurations occurred. At 3 years postsurgery, loss in alveolar ridge width was higher for the BG group (-1.1 ± 0.6 mm) than for the GTH group (0.0 ± 0.3 mm); moreover, these changes were significantly different (P < .0001). This clinical and radiographic data analysis suggests that the implant sites that received a xenogeneic filling material were less effective in maintaining the preoperative alveolar bone width than sites that underwent GTH with immediate implants and anatomical tooth-shaped caps.

Comparative Effects of Different Materials on Alveolar Preservation

The purpose of this study was to compare different materials' effects on alveolar ridge preservation of postextraction sockets in anterior maxilla. In this prospective, single center, randomized, controlled clinical trial, healthy patients who needed one single anterior maxillary tooth extraction (including bicuspids) were selected. After a minimally traumatic extraction without complications, 44 patients were randomly allocated into 4 groups: 1) natural socket healing (blood clot), 2) xenograft and gingival free graft, 3) dense polytetrafluoroethylene membrane, and 4) platelet rich fibrin plugs. Alveolar ridge height and width loss were evaluated in cone beam computed tomography (CBCT) and in dental casts at 3 moments: 1) preoperative (T1), 2) 7days postoperative (T2), and 3) 120days postoperative (T3). Height and width alveolar ridge loss detected in CBCT and in dental casts were compared among the groups (two-way analysis of variance [ANOVA]; P<.05). Forty patients (24 women and 16 men) ranging from 25 to 70years old (mean of 42years old) participated in this study. Group 2 showed the least alveolar ridge height loss results in CBCT (9.8±1.9% at T3) and dental cast analysis (1.0±0.2mm). Groups 2 (12.7±4.7% at T3) and 3 (15.4±2.7% at T3) showed the least alveolar ridge width loss measured in CBCT compared with groups 1 and 4, but the difference between groups 2 and 3 were not statistically significant (P=.968). Group 3 (0.9±0.2mm) and group 2 (1.0±0.2mm) showed the least width loss compared with groups 1 and 4 in dental cast analysis. Again, the difference between groups 3 and 2 was not statistically significant (P=1.000). In postextraction sockets of the anterior maxilla and bicuspid region, group 2 (xenogenous bone graft with free gingival graft) and group 3 (dense polytetrafluoroethylene) obtained the best results in alveolar preservation, with group 2 being more indicated when the vertical alveolar ridge preservation is mandatory.

EVALUATION OF VOLUMETRIC MAINTENANCE AFTER SINGLE AND MULTIPLE DENTAL EXTRACTION USING LAMINATED TITTANIUM SHEET -

The post-extraction border preservation is a fundamental procedure to the maintenance of alveolar volume prioritizing an aesthetical and functional improvement in the im- plant’s positioning. This thesis’s objective was to evaluate the titanium membrane (Sur- gitime Titânio Seal® – Bionnovation, Brasil) covered post extraction alveolar bone di- mensional alterations, while comparing areas to unitary and multiple exodontias. 20 pre and post-operation tomographical exams were evaluated, from areas where unitary den- tal extractions (G1) and multiple dental extractions (G2) occurred. In every case, using the Titanium Seal post extraction alveolar preservation treatment, with no alveolus fil- ling. Measurements were obtained from the central region of the axial and area sections previous to the proceadure at the most cervical zones of bone peaks, plus two more me- asurements from 2 and 4 mm under the first point. Following, those measurements were transfered from the previously obtained absolute refurbishment length. Measurements were taken from the new total border length – at the central virtually representative re- gion of the extracted dental element. In both groups, differences among baseline and 6 months in height: -0,95mm ±0,89 (G1) and -1,95mm ±1,04 (G2) and 2mm volume: -1,10mm ±0,48 (G1) and -2,48mm ±1,08 (G2) were statistically representative. In any cases, the 4mm volume presented differences. Statistically, the bone loss was higher in Group 2. The present study have shown that the titanium-laminated sheet was effective when it comes to post-extraction alveolar preservation, in both unitary and multiple ex- tractions.