Autogenous masticatory mucosal grafts in extraction socket seal procedures: a comparison between sockets grafted with demineralized freeze‐dried bone and deproteinized bovine bone mineral

Successful preservation of the edentulous ridge after extractions may eliminate or reduce the need for ridge augmentation procedures. It has been claimed that grafting fresh extraction sockets and sealing them with autogenous soft tissue grafts promote ridge preservation after tooth extraction. In this study, the survival of free autogenous connective tissue grafts sealing extraction sites was evaluated. In 24 healthy patients, 42 maxillary anterior teeth were extracted. After socket debridement, soft tissue margins of the socket orifice were carefully cut to remove epithelial debris, Sockets were filled with either demineralized freeze-dried bone allografts (DFDBA) or deproteinized natural bovine bone mineral xenograft (DBBMX) to the level of the alveolar bone crest. Circular connective tissue grafts, slightly larger in diameter than the soft tissue socket orifice, were obtained and placed on top of the filler graft material sealing the sockets. Grafts were stabilized and secured by sutures and inspected weekly for the first month. The grafts were classified into 3 groups according to clinical parameters: vital, partially vital and non-vital. After 1 week, 18 grafts were vital, 13 partially vital and 11 non-vital. When only 1 sample unit (1 site per patient) was compared between DFDBA and DBBMX grafted sockets, no significant difference in graft vitality was shown (P = 0.34 for vital; P = 0.67 for vital plus partially vital). After 1 month, all socket orifices were sealed with mucosa. Based on the present observations, it seems that connective tissue grafts sealing fresh extraction sites are mainly dependent on underlying tissue vascularization and that sealing grafted fresh extraction sockets filled with bone substitute allograft or xenograft materials may be beneficial but an unpredictable procedure.     

Socket grafting with the use of autologous bone: an experimental study in the dog

Background: Studies in humans and animals have shown that following tooth removal (loss), the alveolar ridge becomes markedly reduced. Attempts made to counteract such ridge diminution by installing implants in the fresh extraction sockets were not successful, while socket grafting with anorganic bovine bone mineral prevented ridge contraction. Aim: To examine whether grafting of the alveolar socket with the use of chips of autologous bone may allow ridge preservation following tooth extraction. Methods: In five beagle dogs, the distal roots of the third and fourth mandibular premolars were removed. The sockets in the right or the left jaw quadrant were grafted with either anorganic bovine bone or with chips of autologous bone harvested from the buccal bone plate. After 3 months of healing, biopsies of the experimental sites were sampled, prepared for buccal–lingual ground sections and examined with respect to size and composition. Results: It was observed that the majority of the autologous bone chips during healing had been resorbed and that the graft apparently did not interfere with socket healing or processes that resulted in ridge resorption. Conclusion: Autologous bone chips placed in the fresh extraction socket will (i) neither stimulate nor retard new bone formation and (ii) not prevent ridge resorption that occurs during healing following tooth extraction. To cite this article:
Araújo MG, Lindhe J. Socket grafting with the use of autologous bone: an experimental study in the dog.
Clin. Oral Impl. Res. 22 , 2011; 9–13.
doi: 10.1111/j.1600‐0501.2010.01937.x     

Alveolar ridge preservation in the esthetic zone

In the esthetic zone, in the case of tooth extraction, the clinician is often confronted with a challenge regarding the optimal decision‐making process for providing a solution using dental implants. This is because, after tooth extraction, alveolar bone loss and structural and compositional changes of the covering soft tissues, as well as morphological alterations, can be expected. Ideally, the therapeutic plan starts before tooth extraction and it offers three options: spontaneous healing of the extraction socket; immediate implant placement; and techniques for preserving the alveolar ridge at the site of tooth removal. The decision‐making process mainly depends on: (i) the chosen time‐point for implant placement and the ability to place a dental implant; (ii) the quality and quantity of soft tissue in the region of the extraction socket; (iii) the remaining height of the buccal bone plate; and (iv) the expected rates of implant survival and success. Based on scientific evidence, three time‐periods for alveolar ridge preservation are described in the literature: (i) soft‐tissue preservation with 6–8 weeks of healing after tooth extraction (for optimization of the soft tissues); (ii) hard‐ and soft‐tissue preservation with 4–6 months of healing after tooth extraction (for optimization of the hard and soft tissues); and (iii) hard‐tissue preservation with > 6 months of healing after tooth extraction (for optimization of the hard tissues).     

Porcine‐Derived Xenograft Combined with a Soft Cortical Membrane versus Extraction Alone for Implant Site Development: A Clinical Study in Humans

Background: An adequate alveolar crest is essential for implant placement in terms of esthetics and function. The objective of this randomized clinical trial was to compare the preservation of the alveolar ridge dimensions following tooth extraction using porcine‐derived xenograft combined with a membrane versus extraction‐alone (EXT) sites. Methods: Fifteen patients who required double extraction of contralateral premolars and delayed implant placement were randomly selected to receive both ridge‐preservation procedure and EXT. The test sites (alveolar ridge preservation [ARP]) included 15 sockets treated using a corticocancellous porcine bone xenograft (OsteoBiol® Gen‐Os; Tecnoss srl, Giaveno, Italy) associated with a soft cortical membrane (OsteoBiol® Lamina; Tecnoss srl), while the corresponding control sites (EXT) were left without grafting for EXT. Horizontal and vertical ridge dimensions were recorded at baseline and 6 months after extractions. Results: After 6 months, the EXT sites showed a significantly greater reabsorption of the buccolingual/palatal dimension of the alveolar ridge (3.7 ± 1.2 mm) compared with the ARP sites (1.8 ± 1.3 mm). The mean vertical ridge height reduction in the control sockets was 3.1 ± 1.3 mm at the buccal sites and 2.4 ± 1.6 mm at the lingual sites compared with 0.6 ± 1.4 and 0.5 ± 1.3 mm, respectively, in the test sockets. The differences between test and control sockets were not significant for the mesial and distal measurements. Conclusions: The placement of a porcine xenograft with a membrane in an extraction socket can be used to reduce the hard tissue reabsorption after tooth extraction compared with EXT.     

Clinical efficacy of autogenous dentin grafts with guided bone regeneration for horizontal ridge augmentation: a prospective observational study

The aim of this study was to evaluate the efficacy of autogenous dentin grafts with guided bone regeneration (GBR) for horizontal ridge augmentation. Nineteen patients with dentition and bone defects in whom tooth/teeth extraction was indicated were recruited. Autogenous teeth were prepared, fixed on the buccal sides of the defects, and covered with bone powder and resorbable membranes before implantation. The horizontal bone mass at 0 mm (W1), 3 mm (W2), and 6 mm (W3) from the alveolar crest was recorded using cone beam computed tomography, before, immediately after, and 6 months after dentin grafting. All adverse effects were recorded. The implant stability quotient (ISQ) was measured 6 months after implantation. Twenty-eight implants were placed 6 months after dentin grafting. At this time point, the bone mass was 4.72 ± 0.72 mm (W1), 7.35 ± 1.57 mm (W2), and 8.96 ± 2.38 mm (W3), which was significantly different from that before the surgery (P < 0.05). The bone gain was 2.50 ± 0.72 mm (W1), 4.10 ± 1.42 mm (W2), and 4.56 ± 2.09 mm (W3). No soft tissue dehiscence or infection was observed. Overall, 26.3% of the patients experienced severe pain after dentin grafting. The ISQ was 78.31 ± 6.64 at 6 months after implantation. Autogenous tooth roots with GBR might be effective for horizontal ridge augmentation. This technique could be an alternative to augmentation using autogenous bone grafts.     

Use of a modified shell technique for three-dimensional bone grafting: description of a technique

Background: Defects of the alveolar crest often lead to three‐dimensional bone loss after tooth extraction. Therefore, hard tissue grafting is required prior to implant placement. Different techniques have been described in the literature. Methods: In this case report three‐dimensional hard tissue grafting was performed with a modified shell technique and autogenous bone harvested from the mandibular ramus. The shells were trimmed to a thickness of 1 mm and placed to recontour the ideal shape of the alveolar ridge. The shells were then fixed with micro titanium screws, and the gap between the shells and the alveolar ridge was filled with autogenous bone chips. Results: Wound healing was uneventful. Consolidation of the bone graft showed almost no resorption and the implant was placed into vital bone. Conclusions: The described shell technique for rebuilding three‐dimensional alveolar defects showed promising results and could be an alternative treatment to other hard tissue grafting techniques.     

上颌单颗前牙位点保存后邻面牙槽嵴高度的早期变化

目的 探讨位点保存术对上颌单颗前牙拔除后邻面牙槽嵴高度早期变化的影响,为种植修复龈乳头美学效果提供参考依据。方法 选择需拔除上颌单颗前牙的30例患者为研究对象,将其随机分为试验组和对照组,每组15例。试验组在拔牙同时进行位点保存术（牙槽窝内植入 Bio-Oss骨粉,表面游离龈移植缝合固定）,对照组拔牙后未行其他处理。术后7 d及术后6个月,佩戴个性化数字化放射导板行锥形束CT检查,测量2组近远中邻面牙槽嵴及唇侧中央牙槽嵴高度的变化。结果 试验组近中、远中邻面及唇侧中点的牙槽嵴吸收高度分别为（0.358±0.151）mm、（0.322±0.180）mm、（0.826±0.307）mm,对照组近远中邻面及唇侧中点的牙槽嵴吸收高度分别为（0.653±0.260）mm、（0.667±0.274）mm、（1.510±0.625） mm。统计分析表明,试验组的牙槽嵴吸收高度小于对照组（P<0.05）,近中、远中邻面牙槽嵴的吸收高度均小于唇侧（P<0.05）。结论 位点保存术可以减少牙拔除后牙槽嵴高度的吸收,提高种植修复龈乳头美学效果。     

上颌单颗前牙位点保存后邻面牙槽嵴高度的早期变化

目的 探讨位点保存术对上颌单颗前牙拔除后邻面牙槽嵴高度早期变化的影响,为种植修复龈乳头美学效果提供参考依据。方法 选择需拔除上颌单颗前牙的30例患者为研究对象,将其随机分为试验组和对照组,每组15例。试验组在拔牙同时进行位点保存术（牙槽窝内植入 Bio-Oss骨粉,表面游离龈移植缝合固定）,对照组拔牙后未行其他处理。术后7 d及术后6个月,佩戴个性化数字化放射导板行锥形束CT检查,测量2组近远中邻面牙槽嵴及唇侧中央牙槽嵴高度的变化。结果 试验组近中、远中邻面及唇侧中点的牙槽嵴吸收高度分别为（0.358±0.151）mm、（0.322±0.180）mm、（0.826±0.307）mm,对照组近远中邻面及唇侧中点的牙槽嵴吸收高度分别为（0.653±0.260）mm、（0.667±0.274）mm、（1.510±0.625） mm。统计分析表明,试验组的牙槽嵴吸收高度小于对照组（P<0.05）,近中、远中邻面牙槽嵴的吸收高度均小于唇侧（P<0.05）。结论 位点保存术可以减少牙拔除后牙槽嵴高度的吸收,提高种植修复龈乳头美学效果。     

Evaluation of alveolar process resorption after tooth extraction using the socket shield technique without immediate installation of implants: a randomised controlled clinical trial

Our aim was to evaluate resorption of the alveolar ridge using the socket shield technique (SST) without immediate placement of dental implants. This randomised controlled clinical trial included 27 patients: 14 maxillary non-molar teeth were partially extracted using the SST (test group) and 13 were extracted using a minimally traumatic extraction approach (control group). Alterations in height and thickness of the alveolar ridge were evaluated by cone beam computed tomograms taken immediately after, and 100 days after, surgery. Minor resorption was observed in the height of the buccal and palatal plates, without intergroup difference (p ≥ 0.10). The test group showed significantly better preservation of the buccal-to-palatal crest dimension (p ≤ 0.05). In the control group, preservation of buccal plate thickness was significantly greater (p ≤ 0.05), but intragroup vertical resorption of the buccal plate and reduction in the buccal-to-palatal crest distance were greater (p ≤ 0.05). The SST without the immediate placement of implants showed greater preservation of the buccal-to-palatal crest dimension and lower preservation of buccal wall thickness compared with minimally traumatic extraction. In addition, it provided superior maintenance of the baseline buccal wall height. The modified SST is a promising approach, but factors that interfere with the results should be investigated.     

Bio-Oss collagen in the buccal gap at immediate implants: a 6-month study in the dog

Background: Following tooth extraction and immediate implant installation, the edentulous site of the alveolar process undergoes substantial bone modeling and the ridge dimensions are reduced. Objective: The objective of the present experiment was to determine whether the process of bone modeling following tooth extraction and immediate implant placement was influenced by the placement of a xenogenic graft in the void that occurred between the implant and the walls of the fresh extraction socket. Material and methods: Five beagle dogs about 1 year old were used. The 4th premolar in both quadrants of the mandible (₄P₄) were selected and used as experimental sites. The premolars were hemi‐sected and the distal roots removed and, subsequently, implants were inserted in the distal sockets. In one side of the jaw, the marginal buccal‐approximal void that consistently occurred between the implant and the socket walls was grafted with Bio‐Oss^® Collagen while no grafting was performed in the contra‐lateral sites. After 6 months of healing, biopsies from each experimental site were obtained and prepared for histological analyses. Results: The outline of the marginal hard tissue of the control sites was markedly different from that of the grafted sites. Thus, while the buccal bone crest in the grafted sites was comparatively thick and located at or close to the SLA border, the corresponding crest at the control sites was thinner and located a varying distance below SLA border. Conclusions: It was demonstrated that the placement of Bio‐Oss^® Collagen in the void between the implant and the buccal‐approximal bone walls of fresh extraction sockets modified the process of hard tissue healing, provided additional amounts of hard tissue at the entrance of the previous socket and improved the level of marginal bone‐to‐implant contact. To cite this article:
Araújo MG, Linder E, Lindhe J. Bio‐Oss^® Collagen in the buccal gap at immediate implants: a 6‐month study in the dog.
Clin. Oral Impl. Res. 22 , 2011; 1–8.
doi: 10.1111/j.1600‐0501.2010.01920.x     

Modeling of the buccal and lingual bone walls of fresh extraction sites following implant installation

OBJECTIVE: To determine whether the reduction of the alveolar ridge that occurs following tooth extraction and implant placement is influenced by the size of the hard tissue walls of the socket. MATERIAL AND METHODS: Six beagle dogs were used. The third premolar and first molar in both quadrants of the mandible were used. Mucoperiostal flaps were elevated and the distal roots were removed. Implants were installed in the fresh extraction socket in one side of the mandible. The flaps were replaced to allow a semi-submerged healing. The procedure was repeated in the contra later side of the mandible after 2 months. The animals were sacrificed 1 month after the final implant installation. The mandibles were dissected, and each implant site was removed and processed for ground sectioning. RESULTS: Marked hard tissue alterations occurred during healing following tooth extraction and implant installation in the socket. The marginal gap that was present between the implant and the walls of the socket at implantation disappeared as a result of bone fill and resorption of the bone crest. The modeling in the marginal defect region was accompanied by marked attenuation of the dimensions of both the delicate buccal and the wider lingual bone wall. Bone loss at molar sites was more pronounced than at the premolar locations. CONCLUSION: Implant placement failed to preserve the hard tissue dimension of the ridge following tooth extraction. The buccal as well as the lingual bone walls were resorbed. At the buccal aspect, this resulted in some marginal loss of osseointegration.     

拔牙窝内植入不同深度骨水平种植体周围软硬组织改建的组织形态变化

目的 比较新鲜拔牙窝内植入不同深度种植体后软、硬组织的变化。方法 6只成年拉布拉多犬的双侧前磨牙拔除后,立即将24颗种植体以不同深度植入拔牙窝内。将Straumann^®骨水平种植体按以下不同深度植入拔牙窝—颊侧牙槽嵴下2 mm,颊侧牙槽嵴下1 mm,与牙槽嵴齐平,以及颊侧牙槽嵴上方1 mm。愈合6个月后采集样本,获得未脱钙切片,进行组织学观察、测量,获得垂直骨吸收和生物学宽度。采用SPSS 19.0软件包对数据进行统计学分析。结果 所有种植体均获得成功骨结合。骨吸收以种植体植入牙槽嵴下2 mm处最显著（P<0.05）。以不同深度植入时,生物学宽度无显著差别。结论 在新鲜拔牙窝内植入种植体时,不同植入深度对骨吸收有影响。当植入深度为骨下2 mm时,骨吸收最多。     

Alveolar ridge preservation of an extraction socket using autogenous tooth bone graft material for implant site development: prospective case series

This case series evaluated the clinical efficacy of autogenous tooth bone graft material (AutoBT) in alveolar ridge preservation of an extraction socket. Thirteen patients who received extraction socket graft using AutoBT followed by delayed implant placements from Nov. 2008 to Aug. 2010 were evaluated. A total of fifteen implants were placed. The primary and secondary stability of the placed implants were an average of 58 ISQ and 77.9 ISQ, respectively. The average amount of crestal bone loss around the implant was 0.05 mm during an average of 22.5 months (from 12 to 34 months) of functional loading. Newly formed tissues were evident from the 3-month specimen. Within the limitations of this case, autogenous tooth bone graft material can be a favorable bone substitute for extraction socket graft due to its good bone remodeling and osteoconductivity.     

Histologic comparison of healing after ridge preservation using human demineralized bone matrix putty with one versus two different-sized bone particles

Background: Ridge preservation can minimize the loss of alveolar bone subsequent to tooth extraction in preparation for implant therapy. The purpose of this study is to histologically and clinically compare human demineralized bone matrix (DBM) putty with one size of bone particles (SPS) to human DBM putty with two different sizes of bone particles (multiple particle sizes [MPS]) in ridge preservation after molar extractions. Methods: Molar tooth extraction and ridge preservation were performed in 20 participants for each treatment group. Approximately 20 weeks after grafting, core biopsies were obtained during implant placement and analyzed under light microscopy. Specimens were analyzed for the percentage area of vital bone, residual graft particles, and non‐mineralized structures (connective tissue/other non‐mineralized tissue [CT]). Changes in alveolar ridge dimensions were also determined. Results: Sixteen participants in the SPS group and 14 in the MPS group completed the study. The SPS group had a mean of 49% vital bone, 8% residual graft, and 43% CT. The MPS group had 53%, 5%, and 42%, respectively. Patients in both groups lost a mean of <1 mm alveolar height on the buccal and lingual aspects and <1.5 mm of total ridge width. There were no statistically significant differences between the two groups for any clinical or histologic parameters. Conclusion: The results of this study suggest that addition of larger bone particles to DBM putty does not offer additional benefit in the preservation of alveolar bone after the extraction of molar teeth.     

Hard tissue alterations after socket preservation with additional buccal overbuilding: a study in the beagle dog

Objectives: The aim of this study was to histometrically assess alterations of the ridge following socket preservation alone and socket preservation with additional buccal overbuilding.
Material and Methods: In five beagle dogs four extraction sites were randomly subjected to one of the following treatments:
Tx 1: The socket was filled with BioOss Collagen^® and covered with a free gingival graft from the palate.
Tx 2: The buccal bone plate was augmented using the GBR-technique, the socket was filled with BioOss Collagen^® and covered with a free gingival graft.
Tx 3: The buccal bone plate was forced into a buccal direction using a manual bone spreader. The socket was filled with BioOss Collagen^® and covered with a free gingival graft from the palate.
Tx 4: The socket was filled with BioOss Collagen^® and a combined free gingival/connective tissue graft was used to cover the socket and for buccal tissue augmentation.
For each experimental site, two histological sections were subjected to histometric analysis and evaluated for (i) vertical bone dimensions and (ii) horizontal bone dimensions.
Results: All treatment groups showed horizontal and vertical bone loss. The mean vertical bone loss of the buccal bone plate was significantly lower in Tx 4 than in the other groups, while no statistical significant differences could be detected among the groups in the horizontal dimension.
Conclusion: Overbuilding the buccal aspect in combination with socket preservation does not seem to be a suitable technique to compensate for the alterations after tooth extraction.     

Autogenous mandibular bone grafts and osseointegrated implants for reconstruction of the severely atrophied maxilla: a preliminary report

The purpose of this study is to present results obtained with a new procedure for reconstruction of the severely atrophied maxillary alveolar ridge that involves the use of intramembranous corticocancellous bone grafts obtained from the mandibular symphysis fixed to the residual bone by endosseous implants. A total of 107 implants were installed in grafted regions in 26 patients. The follow-up period ranged from 6 to 32 months, with a mean of 16 months. In partially edentulous patients the bone grafts were fixed with implants to the residual bone as 1) onlay graft to the alveolar ridge (8 implants in 4 patients); 2) grafts to the nasal and/or sinus floor after a transoral exposure and elevation of the mucosa of the maxillary sinus and/or the nasal mucosa (33 implants in 11 patients); or 3) a combination of these two (5 implants in 2 patients). In totally edentulous patients, implants and grafts were used as a combination of grafting to both the alveolar ridge and nasal and/or sinus floor sites (61 implants in 9 patients). One hundred of 107 implants showed normal clinical and radiologic healing, whereas 7 implants in 4 patients (6.5%) were lost prior to loading. Seventeen patients have had the implants and bone grafts loaded by a prosthodontic reconstruction from 6 to 26 months (mean, 14 months) without loss of any implants. Postoperative marginal resorption of the onlay bone graft of less than 15% was observed. These findings suggest, that the previously observed rapid resorption of endochondral iliac crest onlay bone grafts and the number of lost implants can be significantly reduced if bone from the mandibular symphysis firmly anchored with titanium implants is used.     

牙槽嵴保存术对不同牙槽骨缺损患者延迟种植效果的影响

目的:探讨牙槽嵴保存术对不同牙槽嵴骨缺损患者延迟种植效果的影响。方法:94例行下颌单颗后牙拔除术患者,根据牙拔除术前牙槽嵴骨缺损量不同将患者分为轻度组(n=53)和中重度组(n=41),行拔牙术后再将轻度组和中重度组分别随机分为保存术组和对照组,保存术组对牙槽窝采取牙槽嵴保存术,对照组对牙槽窝不做处理。结果:轻度组和中重度组患者术后6个月保存术组患者宽度减少量和高度减少量均小于对照组(P<0.05);轻度组和中重度组中保存术组和对照组患者术后6月时GRL较拔牙前增加,而PD和AL则较拔牙前减少;轻度组种植体直径4.1 mm和4.8 mm分别占26.4%和73.6%,而中重度组则分别为46.3%和53.7%,两组相比差异具有统计学意义(χ²=4.029,P=0.045);轻度组种植体长度分布与中重度组相比差异具有统计学意义(χ²=21.207,P=0.000)。结论:牙槽嵴保存术可有效减少拔牙术后植骨区牙槽嵴骨量损失,有利于延迟种植操作的开展,尤其对患牙拔除前牙槽嵴骨缺损量>5 mm的患者,效果尤为显著。     

Staged horizontal bone augmentation for dental implants in aesthetic zones: A prospective randomized controlled clinical trial comparing a half-columnar bone block harvested from the ramus versus a rectangular bone block from the symphysis

In this study, the clinical outcomes of horizontal ridge augmentation using half-columnar bone grafts from the ramus (group I: 27 patients, 32 implants) versus rectangular bone grafts from the symphysis (group II: 19 patients, 27 implants) were compared; grafts were combined with organic bovine bone and collagen membrane. Cone beam computed tomography images were obtained preoperatively, immediately after restoration (baseline), and 1 year after loading. Four months after grafting, horizontal bone resorption at the alveolar crest did not differ significantly between the two groups (P = 0.291). At 4 mm apical to the alveolar crest, horizontal bone resorption in group I was significantly less than that in group II (P = 0.041). One year after loading, horizontal bone resorption in group I was lower than that in group II, with no significant difference. The residual thickness of the labial bone at the implant site in group I was significantly higher than that in group II. Horizontal ridge augmentation with either a half-columnar autogenous graft from the ramus or a rectangular autogenous graft from the symphysis can provide acceptable results in aesthetic regions. The half-columnar group demonstrated better graft stability both at 4 months after augmentation and 1 year after loading.     

前牙美学区牙槽嵴保存延期种植的临床研究

目的 探讨前牙美学区即刻拔牙后采用牙槽嵴保存技术对延期种植的美学修复影响.方法 收集选取2016—2018年于南京医科大学附属口腔医院就诊的患者20例,其中男8例、女12例,所有患者美学区无法保留患牙且骨质缺损较严重,需行前牙美学修复,行前牙微创拔牙,拔牙后即刻行植骨术和胶原膜隔离,引导拔牙窝骨再生,实现位点保存.6个...     

Influence of bioactive glass on changes in alveolar process dimensions after exodontia

BACKGROUND: Preservation of the alveolar process after tooth extraction is desirable because it facilitates placement of endosseous implants and minimizes adverse esthetic results associated with fixed partial dentures. The purpose of this study was to evaluate the clinical effectiveness of bioactive glass used as a graft material combined with calcium sulfate used in the form of a mechanical barrier in preserving alveolar ridges after tooth extraction. METHODS: Sixteen patients who required extraction of 2 anterior teeth or bicuspids participated in the study (split mouth design). After tooth extraction and elevation of a buccal full-thickness flap, experimental sockets were filled with bioactive glass, which in turn was covered with a layer of calcium sulfate. Control sites did not receive any graft or calcium sulfate. Titanium pins served as fixed reference points for measurements. No attempt was made to advance the flap to cover the socket areas on control or experimental sites (open socket approach). Reentry surgeries were performed at 6 months. RESULTS: Reentry surgeries showed that experimental sites presented with (1) significantly more internal socket bone fill (6.43 +/- 2.78 mm vs 4.00 +/- 2.33 mm on control sites), (2) less (although not statistically significantly less) resorption of alveolar bone height (0.38 +/- 3.18 mm vs 1.00 +/- 2. 25 mm on control sites), and (3) similar degree of horizontal resorption of the alveolar bony ridge as compared with controls (3. 48 +/- 2.68 mm vs 3.06 +/- 2.41 mm on control sites). CONCLUSIONS: This study suggests that treatment of extraction sockets with a combination of bioactive glass and calcium sulfate is of some benefit in preserving alveolar ridge dimensions after tooth extraction.