An observational study of the effects of using an high oral splint on pain control

Increasing occlusal vertical dimension (OVD) by means of oral splints is a practice widely used in the treatment of temporomandibular disorders (TMD), specifically myofascial pain, although the results are still uncertain. Oral splints with a vertical height that significantly exceeds the clinical rest position are considered by some researchers to be a better therapeutic solution in alleviating TMD symptoms than are "low" splints. In our observational study, 21 patients suffering from myofascial pain were examined for the effects of wearing a "high" oral splint while sleeping for 3 months. To ensure proper splint making, a mandibular stretching procedure was used to induce a relaxation of the patients' masticatory muscles and allow the correct alignment of the jaws. Results showed a marked increase of the interocclusal distance or "free space" (hence of OVD; from 0.64±0.53 mm to 1.42±0.76 mm, p<0.0001) measured by a kinesiograph, followed by a substantial reduction of the intensity of pain in oral and extraoral regions after using the splint. These results support the view that increasing OVD beyond the clinical rest position is not detrimental to patients' health. More importantly, high oral splints has been shown to be a promising therapeutic aid for the treatment of TMD and correlated pain syndromes. This clinical trial was registered on clinicaltrials.gov (Identifier: NCT02908568).

Reducing dentine hypersensitivity with nano-hydroxyapatite toothpaste: a double-blind randomized controlled trial.

OBJECTIVES: The present randomized double-blind clinical trial aimed to compare the efficacy in reducing dentin hypersensitivity of a dentifrice formulation containing nano-hydroxyapatite with a fluoride dentifrice and a placebo. METHODS AND MATERIALS: One hundred and five subjects were recruited to participate in the study. A computer-generated random table with blocking to one of the three study treatments was used in order to have 35 subjects per group: (1) nano-hydroxyapatite 2% gel toothpaste fluoride free; (2) fluoride gel toothpaste; (3) placebo. Groups 1, 2, and 3 were instructed to treat their teeth for 10 min twice a day with the provided toothpaste gel. The participant's dentin hypersensitivity was evaluated at baseline and after 2 and 4 weeks using airblast and tactile tests. In addition, a subjective evaluation using a visual analogue scale was used. RESULTS: Significant lower values of cold air sensitivity and tactile sensitivity (p < 0.05) were found for the test group at 2 weeks and 4 weeks. In addition, statistically significant (p < 0.05) lower values of sensitivity were reported for group 1 compared to those for groups 2 and 3 at 2 and 4 weeks, respectively. The VAS scores were significantly lower (p < 0.05) in the test group at 2 and 4 weeks compared to those at baseline and in the control groups. CONCLUSION: The application of nano-hydroxyapatite in gel toothpaste fluoride free is an effective desensitizing agent providing relief from symptoms after 2 and 4 weeks.

A novel CAD/CAM-based surgical template for mandibular osteoplasty and guided implant insertion.

Bone shaping is often a necessary procedure prior to implant insertion in mandibular full-arch rehabilitations. Adopting guided surgery procedures is necessary to use two distinct templates: one for bone shaping, a second for guided implant insertion. The present report describes the case of a 60-year-old patient requiring a full-arch, immediately loaded implant-supported mandibular rehabilitation. A CAD/CAM-bone supported surgical template for osteoplasty was used to develop a template for guided implant during an all-on-six immediate-loaded computer-aided implant surgery. The report describes the feasibility, accuracy and usefulness of this double, CAD/CAM developed, surgical template.

The efficacy of 0.12% chlorhexidine versus 0.12% chlorhexidine plus hyaluronic acid mouthwash on healing of submerged single implant insertion areas: a short-term randomized controlled clinical trial.

OBJECTIVES: The study was performed to evaluate the incidence of post-surgical adverse events at submerged implant sites as well as the antiplaque, antigingivitis and antistaining effects in the entire dentition of patients treated with two mouthwashes. METHODS: The present randomized controlled clinical study considered 40 patients subjected to dental implant treatment. Two 0.12% chlorhexidine mouthwashes were compared for 15 days: one with 0.1% hyaluronic acid (CHX⊗HYL group) and one without it (CHX group). Surgical outcome variables, and plaque, gingival, and staining indexes were recorded. RESULTS: Significant differences were found between the two rinses regarding the presence of oedema within 2 days after surgery (20% for the CHX⊗HYL group and 78% for the CHX group). No other significant differences were recorded between the two mouthwashes. No intergroup differences in plaque, staining and gingivitis indexes were registered. The intragroup analysis revealed that for the plaque and gingival indexes, the differences between the baseline values (before surgery) and those at 15 days were all found to be significant just for CHX⊗HYL rinse, with final values ranging from 0.18 to 0.23 for the plaque index and from 0.06 to 0.07 for the gingival index. The staining index increased for both mouthwash types with significant results (with final value of 0.19 and 0.31 for CHX⊗HYL and CHX groups, respectively). CONCLUSIONS: In the sites of patients subjected to dental implant placement, an additional anti-oedematigenous effect in early healing seemed to be disclosed for 0.12% CHX⊗HYL mouthwash. Regarding antiplaque and antigingivitis activities, HYL seemed to be ineffective.

Tooth bleaching with hydrogen peroxide and nano-hydroxyapatite: a 9-month follow-up randomized clinical trial.

OBJECTIVES: The aim of this study was to compare the amount of tooth colour change, rebound rate and tooth sensitivity in patients submitted to a bleaching technique with 6% hydrogen peroxide (HP) with or without 2% nano-hydroxyapatite (n-HA). METHODS: Sixty subjects were included in this examiner-blinded, randomized clinical trial using a 6% HP gel with or without 2% n-HA. Tooth colour and tooth sensitivity were analysed before and after treatment. All data were analysed statistically. RESULTS: After bleaching, both treatments demonstrated significant improvements in tooth shade (P < 0.05 for both groups). At the 9-month recall, tooth shade remained significantly lighter than at baseline (P < 0.05 for both groups). However, a relapse of the tooth shade was observed compared with the immediate post-bleaching result (P < 0.05). 6% HP with 2% n-HA produced significantly lower sensitivity (P < 0.05) than the bleaching product without n-HA. Colour change evaluation resulted in no difference between the two groups. CONCLUSION: Both treatments demonstrated significant improvements in tooth shade. The bleaching effectiveness of the tested products was comparable. The use of 6% HP with 2% n-HA reduced the incidence of sensitivity during the bleaching treatment compared to a bleaching agent that did not contain n-HA.

Changes in soft tissues around immediate full-arch rehabilitations: a prospective study.

INTRODUCTION: Nowadays, aesthetic appearance is receiving more and more attention from clinicians and patients. Therefore, it is of paramount importance for the surgeon to maintain or to improve the quality and the stability of the soft tissue-implant interface. The scientific literature supports the idea that the immediate placement and provisionalization of endosseus implants and abutments can indeed offer additional clinical control over the peri-implant tissue architecture. On this basis, this prospective study aims to evaluate the changes in soft tissues around immediately loaded dental implants in full-arch rehabilitations, over a period of 3 months. MATERIALS AND METHODS: Fifteen subjects were treated for immediate full-arch rehabilitations. Following implant placement, provisional rehabilitations made of bisphenol-A-glycidyldimethacrylate (BIS-GMA) and resin were placed. All records were made using a periodontal probe. The facial soft-tissue level was measured evaluating the distance between the soft-tissue margin and the incisal edge of the crown. Moreover, papilla levels were measured at the mesial and distal sites from a reference line connecting the occlusal edge of the crowns. RESULTS: The average value at the mesial site was -0.035 mm (±1, median 0 mm), while at the midfacial site, it was 0 mm (±0.76, median 0 mm) and at the distal site, -0.05 mm (±0.92, median 0 mm). The plaque score index showed a reduction during the follow-up period. DISCUSSION: Our data indicate that no differences at the midfacial point were detectable over the observation period. This is in agreement with several studies; it is plausible that these results are linked to a correct position of the implant in the alveolar socket. Moreover, comparing our results with what has been reported by other authors, it is surprising that while other studies highlight that papilla loss at the mesial and distal aspect is an expected consequence of immediate implant restorations, our data do not show any changes. The explanation of these results remains unclear. Further studies are needed to support our data and to clarify what mechanisms are involved in the maintenance of soft tissue.

A 6-month histological analysis on maxillary sinus augmentation with and without use of collagen membranes over the osteotomy window: randomized clinical trial.

INTRODUCTION: Over the years, several modifications have been made to the sinus augmentation technique and to the materials used. However, there is still controversy about the need for using a barrier concurrently with a graft in sinus augmentation procedures. On this basis, the aim of this randomized clinical study was to investigate the effect of resorbable collagen membrane over the osteotomy window on maxillary sinus augmentation healing. MATERIALS AND METHODS: Patients who required maxillary sinus augmentation were evaluated and selected to enter the study. After maxillary sinus grafting, each patient was randomly assigned to control (membrane over the osteotomy window) or test (no membrane) group. After 6 months, one bone biopsy was harvested from the lateral window and sent to the histology laboratory. The Mann-Whitney nonparametric test was used for comparing the two groups. P-value was set at 5%. RESULTS: Eighteen patients entered the study and were randomly allocated in control (nine patients) or test group (nine patients). The histomorphometric measurements revealed that newly formed bone was 30.7% ± 15.5% of the total volume from the membrane group (control). The average percentage of connective tissue was 50.6% ± 18.7% and residual graft percentage was 18.4% ± 20.3%. On the other hand, data regarding the nonmembrane group (test) showed that the percentage of newly formed bone was 28.1% ± 19.4%. The mean percentage of connective tissues was 59.3% ± 15.4% and 12.6% ± 12.4% for the residual graft particles. No significant difference was detected in the histomorphometrical evaluation between the two groups. DISCUSSION: Our results showed that, compared with sites not covered, the use of the membrane did not substantially increase the amount of vital bone over a period of 6 months. On the other hand, the use of membrane seems to reduce the proliferation of the connective tissue and the graft re-absorption rate. It is plausible that blood supply of maxillary sinus can play a role in such a result. Further studies are needed to explore whether the use of membrane could really be advantageous for the sinus augmentation procedure and to evaluate what influence this method can have on the amount and quality of reconstructed bone.

Sub-micrometric liposomes as drug delivery systems in the treatment of periodontitis.

Periodontitis is a complex disease and bacterial infection is one of the most common factors involved in this disease. Current strategies for the local delivery of antibiotics do not allow a complete clearance of bacteria filling dentinal tubules and this limits their therapeutic efficacy. Therefore, there is a strong need for the development of new delivery strategies aimed at improving the efficacy of antibiotic therapy for periodontitis with special reference to their ability to penetrate into the tubules. The aim of the present study is to develop liposome-based delivery systems of sub-micron dimension, able to diffuse into the dentinal tubules. A further aim of the research is to develop a protocol for enhanced diffusion based on the use of magnetic liposomes and magnetic fields. Liposomes were produced by hydration of a pre-liposomal formulation. The vesicles were stabilised with PEG and their re-sizing was achieved by extrusion. Magnetite nanoparticles were synthesized inside the vesicles, i.e., the chemical reaction involving FeCl2, FeCl3 and NH3 occurred within the core of the newly formed liposomes. Dynamic light scattering analysis was performed for size characterization. A mathematical model was implemented to predict the diffusion of the liposomes in dentinal tubules. Ex-vivo validation was performed on extracted human teeth. We produced PEG-ylated liposomes (average size 204.3 nm) and PEG-ylated magnetic liposomes (average size 286 nm) and an iron content of 4.2 µg/ml. Through mathematical modelling, we deduced that sub-micrometer vesicles are able to penetrate into dentinal tubules. This penetration is considerably more effective when the vesicles are magnetized and subjected to an external magnetic field which accelerates their movement within the tubules. The liposome-based delivery systems developed by the present study are able to penetrate deeply into the tubules, sometimes reaching their terminal ends.

Periodontal dressing may influence the clinical outcome of non-surgical periodontal treatment: a split-mouth study.

INTRODUCTION: After scaling and root planning (SRP), healing induces the formation of a junctional long epithelium rather than a new connective attachment. We hypothesize that the placement of a periodontal dressing will be able to prevent detachment of coagulum inducing proper healing and improving periodontal parameters. MATERIALS AND METHODS: This split-mouth study included 30 patients with periodontitis with ages ranging from 35 to 70 years. Probing pocket depth (PD), probing attachment level (PAL), bleeding on probing index (BoP) and plaque index (PI) were assessed before and after therapy. The group of patients received SRP in a span of 24 h. Then, a periodontal dressing was applied on the test side and it was removed after 1 week. CONTROL GROUP: The difference between PD values at baseline and after therapy was 1.6 ± 0.6 mm. The difference in PAL (ΔPAL) measurement was 1.4 ± 0.4. Test group: there was a greater PD reduction, this being 2.4 ± 0.6 mm on average. The difference in PAL was 2.5 ± 0.4 mm. CONCLUSIONS: Our results clearly suggest that the use of a periodontal dressing improves the periodontal parameters after an SRP procedure. This is probably due to clot stabilization and prevention of bacterial colonization during wound healing.

Bone remodelling after regenerative procedures around implants placed in fresh extraction sockets: an experimental study in Beagle dogs.

INTRODUCTION: After a tooth extraction, the height of the buccal wall tends to decrease. The literature indicates that regenerative techniques (guided bone regenerative [GBR] techniques) have succeeded in improving the bone levels. Therefore, this experiment set out to compare the physiological bone remodelling in Beagle dog models after implant placement in a fresh extraction socket, with and without the application of regenerative procedure. MATERIALS AND METHODS: Five dogs were used in this study. Test and control sites were randomly selected. The experimental teeth (fourth pre-molar and first molar) were hemi-sected removing the distal roots and placing implants. Porcine bone was placed to fill the gap around the implant on the test sites and a reabsorbable membrane was used to cover the area. The dogs were put down at different times (2 weeks, 1 month and 3 months). The measurements were taken immediately and at 2, 4, 12 weeks after implant placement. Student's test for paired data was used to compare the means of the clinical measurements. RESULTS: At 2 weeks: On the control sites, few signs of resorption were detected at the first molar only, while at the test sites bone levels were placed at the implant shoulder or above. At 4 weeks: On the control site, slight bone remodelling was observed, while on the test site minor signs of resorption or an increase of bone levels were detected. At 12 weeks: The alveolar crest on the control sites showed various degrees of remodelling. On the test sites stable bone levels or an increase of bone crest was observed. CONCLUSION: With the limits of this study, the findings showed that GBR techniques were able to limit resorption of the alveolar crest after tooth extraction. A pattern of bone remodelling after tooth extraction and implant placement was observed in the control sites (no GBR) as well as in test sites (GBR), and although the exact cause of this is unclear, surgical trauma could play a role. Further studies are necessary to confirm these results and to clarify the precise causes of bone remodelling in fresh extraction sockets.

Analysis of the pattern of the alveolar ridge remodelling following single tooth extraction.

INTRODUCTION: Tooth extraction is followed by marked osseous changes of the residual alveolar ridge including severe bone alterations both in height and in width. However, such remodelling could jeopardize the subsequent implant insertion for two main reasons. Firstly, the absence of adequate bone levels makes implant placement impossible; secondly, aesthetic problems in the fabrication of implanto-supported restoration could be caused by serious bone re-absorption. Thus, it is of crucial importance that the dental surgeon knows how the alveolar crest changes when a single tooth has been removed. The aim of this study was to evaluate the pattern of alveolar crest remodelling observed in a single intercalated area of tooth extraction after at least a period of 6 months of healing, using standardized photos of model casts. MATERIAL AND METHODS: Among the patients who were treated for a single intercalated tooth extraction during the last 2 years at the department of dentistry at Versilia Hospital, Lido di Camaiore (Lucca), Italy, we selected 50 patients. The amount of alveolar crest remodelling was assessed on standardized photos of study models. All measurement were recorded on an Excel sheet (Excel, Windows XP(®)) and each value was multiplied by the enlargement index so that true values of re-absorption could be obtained. Finally, we have calculated the percentage of amount of alveolar crest remodelling and shifting of alveolar crest. RESULTS: We calculated the percentage of buccal remodelling and alveolar crest shift. The buccal re-absorption was 19.4 ± 9.4% at mesial point, 39.1 ± 10.4% at midpoint and 20.3 ± 10.7% at distal level. Moreover, the shift of the alveolar crest was 59.1 ± 11.2% at mesial point, 64.8 ± 10.5% at the midpoint and 56 ± 12.5% at distal point. CONCLUSIONS: This study confirmed that buccal wall tends to re-absorb after the extraction according to a specific pattern. Thus, the re-absorption at the midpoint represent the double of bone loss at the distal and the mesial points. Furthermore, we have observed first how the alveolar crest shifts placing along the more lingual/palatal line which divides the original alveolar crest into three parts.

Alveolar socket remodeling: The tug-of-war model.

Bone change after tooth extraction has been well documented by different studies. Tooth extraction is followed by loss in height and width of the alveolar process. After tooth loss, the natural healing process is governed by the formation of the blood clot, which is stabilized by a fibrin bridge, the starting structure for new bone apposition. The hematoma is then replaced by the granulation tissue which is rich in fibroblasts that synthesize the extra-cellular matrix. The adjoining of wound edges requires further contraction of the healing tissue which is exerted by myofibroblasts. Excessive myofibroblasts contraction at the early stage of healing might explain, in part, the pathophysiology of alveolar bone resorption. The authors advocate the use of collagen right after tooth extraction to sustain the soft tissue and releasing the tension at the most coronal portion of the wound, thus preventing excessive detrimental myofibroblasts contraction.

A short-term study of the effects of ozone irrigation in an orthodontic population with fixed appliances.

AIM: The aim of the present study was to compare the clinical efficacy of chlorhexidine and ozonised water in the oral hygiene maintenance of orthodontic patients. MATERIALS AND METHODS: Study design: This is a prospective clinical study. Thirty patients with orthodontic brackets were selected at the Versilia General Hospital (Lido di Camaiore, Italy). Patients were randomly allocated to one of two groups: standard oral hygiene session followed by prescription of either chlorhexidine mouth-rinse or ozonated water. At each moment of the follow-up, the following parameters were recorded: pocket probing depth (PPD), full-mouth plaque index (FMPI), and full mouth bleeding score (FMBS). STATISTICS: Sample size was computed according to previously published data. Significance level was set at 0.05 for all analyses, and non-parametric Wilcoxon signed rank test was used for comparisons. RESULTS: At baseline, mean PPD was 1.89 ± 0.13 mm for the control group and 1.95 ± 0.10 mm for the test group. Mean FMPI was 63.9 ± 16.5% and 68.7 ± 10.33% respectively. Mean FMBS was 31.5 ± 15.6% and 32.8 ± 8.85 respectively. One month after treatment (T2), both groups showed a significant improvement of FMPI and FMBS. Mean FMPI was 42.8 ± 14.3% and 24.3 ± 6.41% respectively. Mean FMBS was 19.5 ±12.6% and 4.70 ± 3.56% respectively. The test group treated with ozone exhibited a greater improvement of FMPI and FMBS. CONCLUSIONS: Ozone yielded better outcomes than chlorhexidine in the management of gingivitis in orthodontic patients. Ozone should be further investigated in longitudinal studies with larger samples.

Root surface morphological changes after focused versus defocused CO2 laser irradiation: a scanning electron microscopy analysis.

BACKGROUND: Many studies have observed damages to root surfaces treated by CO2 laser in continuous mode with a focused beam. The morphologic changes observed were always associated with temperature increase induced by high energy release. METHODS: The purpose of this study was to analyze by scanning electron microscopy (SEM) the effects of CO2 laser in 2 different modes on root surfaces. Study samples consisted of 30 extracted single-rooted periodontally compromised human teeth. Root specimens were randomly assigned to 3 groups: group A (12) treated with CO2 laser in continuous mode with a focused beam of 0.8 mm; group B (12) treated with CO2 laser in pulsed mode with defocused beam of 4 mm; and group C (6), untreated controls. RESULTS: Group A (continuous mode) showed severe damages to dentin surfaces such as craters and fissures. Group B (defocused mode) did not result in any damages to the root surfaces, showing flat and smooth surfaces with apparent fusion of the smear layer and dentinal tubules almost completely sealed. The untreated control group was characterized by irregular and amorphous surfaces with several shallow depressions. CONCLUSIONS: Although both laser modes resulted in changes to the treated root surface specimens, the changes resulting in a smooth surface from use of defocused pulsed beam may present an advantage in periodontal treatment.

Effects of CO2 laser treatment on fibroblast attachment to root surfaces. A scanning electron microscopy analysis.

BACKGROUND: The aim of this study was to analyze the CO2 laser effects on root surfaces affected by periodontal disease in comparison to scaling and root planing for fibroblast attachment. METHODS: Thirty single-rooted human teeth extracted because of advanced periodontal disease were included in this study. A total of 60 specimens, obtained from all selected teeth, were randomly assigned to 3 groups: 1) control (untreated); 2) hand scaling and root planing (SRP); or 3) laser (CO2 defocused pulsed) and ultrasonic scaling. All the specimens were incubated in Petri dishes with fibroblast suspension, and then observed by scanning electron microscopy (SEM). RESULTS: The control group showed the lowest number of attached cells, with no tightly attached fibroblasts. The laser plus scaling group showed the highest number of attached fibroblasts, with the tightly attached fibroblast prevailing. The laser-treated and scaled root specimens did not show any damage or morphologic alteration of the root surfaces. CONCLUSION: CO2 laser treatment in defocused, pulsed mode with a low power of 2W combined with mechanical instrumentation constitutes a useful tool to condition the root surface and increase fibroblast attachment to root surfaces.

New directions in surgical endodontics; immediate implantation into an extraction site.

Endodontic surgical procedures may reveal compromising factors that indicate a modification of the treatment (e.g. tooth extraction, root amputation, etc.). To take advantage of the osseous height and width, as well as the natural tooth angulation, immediate placement of implants after extraction is a reasonable alternative treatment. In this study, 32 titanium alloy implants were inserted immediately after extraction of teeth diagnosed during endodontic surgery as having root fractures, perforations, or endodontic-periodontal complications. After 4 to 6 months of osseointegration, only one implant failed to integrate, and the remaining implants were prosthetically restored. Sixteen months after occlusal loading, bone loss was approximately 1.5 mm for the 31 implants remaining. It seems that the immediate placement of implants following tooth extraction due to endodontic complications is a reliable procedure.

Simultaneous implant placement and vertical ridge augmentation with a titanium-reinforced membrane: a case report.

The present report demonstrates a clinical approach to achieve vertical ridge augmentation around endosseous implants. Two implants were placed, leaving the threads exposed, in the atrophic mandibular right posterior quadrant of a male patient. Both implants were covered with a titanium-reinforced expanded polytetrafluoroethylene (e-PTFE) membrane. Second-stage surgery was performed 12 months after implant placement. Upon membrane removal, growth of mineralized tissue was observed around both implants, covering areas previously not covered by bone. Implants were then progressively loaded and restored. Titanium-reinforced e-PTFE membranes can be satisfactorily used for vertical augmentation of atrophic ridges.

Immediate one-stage postextraction implant: a human clinical and histologic case report.

The placement of an implant immediately after tooth extraction may have the following advantages: reduction in morbidity, treatment time, and treatment costs; preservation of the residual ridge width and height; optimal esthetic result; and easier definition of implant position. The aim of the present study was the presentation of a human clinical and histologic report involving a nonsubmerged implant placed in a mandibular postextraction site and removed because of persistent pain. At low-power magnification, it was possible to see that newly formed bone with wide osteocyte lacunae was present around the implant. A 1.5-mm sulcular epithelium was visible on one side of the implant, with a 0.5-mm epithelial attachment. The thickness of the supracrestal connective tissue was 3.2 mm. This connective tissue was dense, had few cells, was well vascularized, and showed no evidence of an inflammatory infiltrate. Under polarized light, it was possible to observe that the connective fibers were arranged perpendicular to the implant surface and that these fibers became parallel near the implant. These results show that human immediate postextraction implants can have a high percentage of bone-implant contact.

Bone regeneration with a calcium sulfate barrier.

OBJECTIVES: Bone defects are a challenge for the dental clinician. As widely accepted in guided tissue regeneration, physically halting soft connective tissue proliferation into bone allows for bone regeneration. This concept is the "osteopromotion principle." The aim of this study was to assess the osteopromoting effect of calcium sulfate as a barrier. STUDY DESIGN: Forty male Sprague-Dawley rats were used. Mucoperiosteal flaps were raised bilaterally at buccal and lingual aspects of the mandible to expose the angles. Next, 5 mm through-and-through bony defects were created bilaterally. On the test side, sterile medical grade prehardened calcium sulfate disks were applied both lingually and buccally to cover the defect. The control side defects were left uncovered. All flaps were sutured closed. Observation times were 3, 9, 18, and 22 weeks. RESULTS: Histologic analysis demonstrated that at 3 weeks all test sites showed partial or complete bone healing. Similar findings were reported for all observation times. The control group showed no bone growth at 3 and 9 weeks and partial bone healing at 18 and 22 weeks. CONCLUSIONS: This study indicates that calcium sulfate barriers can exclude connective tissues, allowing bone regeneration during healing.