A radiographic and histological study to compare red (650 nm) versus near infrared (810 nm) diode lasers photobiomodulation for alveolar socket preservation.

Previous findings indicated that the laser photobiomodulation is more effective than the control or placebo in preserving the alveolar socket. This study aimed to compare two different lasers regarding their effectiveness in aiding alveolar socket preservation. Twenty extraction sockets were selected then divided into two equal groups. Group A was exposed to 650 nm Diode laser, and Group B to 810 nm Diode laser following the same protocol and parameters after a standard alveolar socket preservation procedure with collagen plug. Radiographic analysis with cone beam computed tomography was done to compare the alveolar bone surface area immediately after extraction and three months post-operatively, while bone samples collected before implant drilling were histologically examined for newly formed bone evaluation and histomorphometric analysis in terms of percentage of new bone surface area, percentage of unmineralized bone and finally, immunohistochemical analysis of Osteocalcin reaction surface area as well as optical density. Radiographically, infrared (810 nm) Diode effect on alveolar bone surface area has significantly exceeded the red laser, while histologically, red (650 nm) Diode has demonstrated statistical significance regarding all parameters; newly formed bone surface area percentage, unmineralized bone area percentage and finally Osteocalcin bone marker reaction surface area percentage and optical density. Under the specified conditions and laser parameters, photobiomodulation using the 810 nm Diode got the upper hand radiographically, yet histologically, the red 650 nm Diode managed to dominate all histological parameters when both employed as an adjunct to alveolar socket preservation procedures.

Astaxanthin Inhibits Diabetes-Triggered Periodontal Destruction, Ameliorates Oxidative Complications in STZ-Injected Mice, and Recovers Nrf2-Dependent Antioxidant System.

Numerous studies highlight that astaxanthin (ASTX) ameliorates hyperglycemic condition and hyperglycemia-associated chronic complications. While periodontitis and periodontic tissue degradation are also triggered under chronic hyperglycemia, the roles of ASTX on diabetes-associated periodontal destruction and the related mechanisms therein are not yet fully understood. Here, we explored the impacts of supplemental ASTX on periodontal destruction and systemic complications in type I diabetic mice. To induce diabetes, C57BL/6 mice received a single intraperitoneal injection of streptozotocin (STZ; 150 mg/kg), and the hyperglycemic mice were orally administered with ASTX (12.5 mg/kg) (STZ+ASTX group) or vehicle only (STZ group) daily for 60 days. Supplemental ASTX did not improve hyperglycemic condition, but ameliorated excessive water and feed consumptions and lethality in STZ-induced diabetic mice. Compared with the non-diabetic and STZ+ASTX groups, the STZ group exhibited severe periodontal destruction. Oral gavage with ASTX inhibited osteoclastic formation and the expression of receptor activator of nuclear factor (NF)-κB ligand, 8-OHdG, γ-H2AX, cyclooxygenase 2, and interleukin-1ß in the periodontium of STZ-injected mice. Supplemental ASTX not only increased the levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and osteogenic transcription factors in the periodontium, but also recovered circulating lymphocytes and endogenous antioxidant enzyme activity in the blood of STZ-injected mice. Furthermore, the addition of ASTX blocked advanced glycation end products-induced oxidative stress and growth inhibition in human-derived periodontal ligament cells by upregulating the Nrf2 pathway. Together, our results suggest that ASTX does not directly improve hyperglycemia, but ameliorates hyperglycemia-triggered periodontal destruction and oxidative systemic complications in type I diabetes.

Impact on patients with oral squamous cell carcinoma in different anatomical subsites: a single-center study in Taiwan.

The incidence of oral cavity squamous cell carcinoma (OSCC) is particularly high in South Asia. According to the National Comprehensive Cancer Network, OSCC can arise in several subsites. We investigated survival rates and the clinical and pathological characteristics of OSCC in different anatomical subsites in the Taiwanese population. We retrospectively analyzed data for 3010 patients with OSCC treated at the Changhua Christian Hospital. Subsequently, we compared clinical and pathological features of OSCC in different subsites. Pathological T4 stage OSCCs occurred in the alveolar ridge and retromolar trigone in 56.4% and 43.7% of cases, respectively. More than 25% of patients with tongue OSCC and 23.4% of those with retromolar OSCC had lymph node metastasis. The prognosis was worst for hard palate OSCC (hazard ratio 1.848; p < 0.001) and alveolar ridge OSCC (hazard ratio 1.220; p = 0.017). Retromolar OSCC recurred most often and tongue OSCC second most often. The risk for cancer-related mortality was highest for hard palate OSCC, followed by alveolar ridge and retromolar OSCC. We found distinct differences in survival among the different subsites of OSCC. Our findings may also help prompt future investigations of OSCC in different subsites in Taiwanese patients.

Impact of Hyperbaric Oxygen on the Healing of Bone Tissues Around Implants.

PURPOSE: The impact of hyperbaric oxygen (HBO) on the healing of bone tissues around implants was studied using an animal model. METHODS: A total of 32 beagle dogs were selected and randomly divided into the HBO group and the blank group. The dogs in the HBO group were subjected to 90 minutes of HBO therapy. X-ray, cone-beam computerized tomography imaging, implant stability quotient (ISQ) values, histological observation, quantitative analysis of bone histomorphometry, and hematoxylin-eosin (HE) and Masson staining were evaluated. RESULTS: In this study, at 4 weeks after the surgery, the mean ISQ value in the HBO group was higher than that in the blank group, and the difference had statistical significance (P < 0.05). At week 4 and 8, the mean values of bone ingrowth fraction (BIC%) and the percentage of bone area (BA%) in the HBO group were both higher than those of the blank group. Decalcified paraffin sections were stained with HE and Masson staining showed that the bone tissue around the implant in the HBO group has more osteoblasts than control group, and many irregular marrow cavities and Haversian bone plates were observed in the new bone tissue. CONCLUSION: This study showed that after implantation, early osteogenesis was better in the HBO group than in the blank group. On one hand, the healing time of the bone tissue around the implants was reduced.

The effect of daily intake of green coffee bean extract as compared to Agiolax® on the alveolar bone of albino rats.

BACKGROUND: Obesity is a worldwide medical problem in which excess body fat is accumulated in the body. The use of weight loss supplements such as green coffee bean extract and Agiolax has become a common trend among people who want to lose weight in a fast and non-tiring way. As a result of their effect on fluid excretion, both of these products may be expected to have a damaging effect on the alveolar bone. OBJECTIVES: The aim of the present study was to evaluate the histopathalogical effect of green coffee bean extract as compared to Agiolax on the alveolar bone of albino rats. MATERIAL AND METHODS: Twenty-seven adult male albino rats were randomly assigned to 3 groups. Nine received distilled water daily for 2 months by oral gavage (the control group); the other 2 groups received 1 mg/100 g body weight green coffee bean extract or Agiolax 8 mg/100 g body weight daily for 2 months by oral gavage (the GC and Ag groups, respectively). The alveolar bones were dissected and examined histologically, histomorphometrically and by western blotting. RESULTS: The bone area percentage and the calcium level in serum were significantly decreased in the GC and Ag groups, while the calcium level in urine was significantly increased in both the experimental groups as compared to the control group. On the other hand, RANKL expression was significantly increased only in the GC group, and the tissue calcium (Ca) level was significantly decreased only in the GC group as compared to the control group. CONCLUSIONS: Long-term oral administration of green coffee bean extract and Agiolax might lead to alveolar bone loss. A greater deleterious effect was caused by green coffee bean extract, as it caused more RANKL expression, significantly reduced Ca level in the tissue and consequently decreased the bone area percentage.

Bone Formed After Maxillary Sinus Floor Augmentation by Bone Autografting With Hydroxyapatite and Low-Level Laser Therapy: A Randomized Controlled Trial With Histomorphometrical and Immunohistochemical Analyses.

PURPOSE: The aim of this study was to evaluate the bone formed after maxillary sinus floor augmentation (MSFA) by bone autografting combined with hydroxyapatite (HA) that had been either treated with low-level laser therapy (LLLT) or not. MATERIALS AND METHODS: Twelve biopsies were obtained from patients 6 months after MSFA using a combination of 50% of autogenous bone (AB) and 50% of HA (AB/HA group, n = 6) followed by LLLT (AB/HA-LLLT group, n = 6). The laser used in this study was gallium-aluminium-arsenide laser with a wavelength of 830 nm (40 mW; 5.32 J/point; 0.57 W/cm). Samples obtained were subjected to histological, histometric, and immunohistochemical analysis for detection of tartrate-resistant acid phosphatase and runt-related transcription factor 2. The data were submitted to statistical analysis (Shapiro-Wilk and Student t tests; α = 5%). RESULTS: Statistical analysis revealed no significant difference in vital bone presence and immunohistochemical analysis between the groups. There was no reduction in bone marrow or fibrous tissue in the AB/HA group and AB/HA-LLLT group. There was a decrease in the amount of remaining biomaterial between the groups (P = 0.0081). CONCLUSION: LLLT did not increase the formation of new bone; instead, it accelerated the bone remodeling process.

Comparative evaluation of various low-level laser therapies on bone healing following tooth extraction: An experimental animal study.

PURPOSE: The aim of this study was to evaluate the effects of helium-neon and gallium-aluminum-arsenide lasers with various doses on bone healing following tooth extraction. MATERIALS AND METHODS: Maxillary right incisor teeth of 30 female albino Wistar rats were extracted. Five groups were established: four groups treated with helium-neon or gallium-aluminum-arsenide lasers and a control group. Both laser groups' rats received energy doses of 6 J/cm2 and 10 J/cm2 for 7 days. At the end of 30 days, all subjects were sacrificed for histological and morphological evaluations. RESULTS: Laser groups showed faster bone healing and gallium-aluminum-arsenide lasers increased vascular immunoreactivity. The most widespread organized bone formation in the extraction socket was observed in the gallium-aluminum-arsenide laser group with the energy dose of 10 J/cm2 (p < 0.05). CONCLUSION: This study demonstrated that low-level laser therapies were effective on alveolar bone healing and that an energy dose of 10 J/cm2 did not have an inhibition effect on bone regeneration.

Morphometric and histopathological evaluation of the effect of grape seed proanthocyanidin on alveolar bone loss in experimental diabetes and periodontitis.

OBJECTIVE: Grape seed proanthocyanidine extract (GSPE) is a strong antioxidant derived from the grape seeds (Vitis vinifera, Terral J.F.) and has a polyphenolic structure with a wide range of biological activity. The aim of the present study was to evaluate the effects of GSPE on alveolar bone loss and histopathological changes in rats with diabetes mellitus and ligature-induced periodontitis. MATERIAL AND METHODS: Forty rats were divided into 6 study groups. Control (C, 6 rats) group, periodontitis (P, 6 rats) group, diabetes (D, 6 rats) group, diabetes and periodontitis (D+P, 6 rats) group, diabetes, periodontitis and 100 mg/kg/day GSPE (GSPE-100, 8 rats), and diabetes, periodontitis and 200 mg/kg/day GSPE (GSPE-200, 8 rats) group. Diabetes mellitus was induced by intraperitoneal injection of a single dose of streptozotocin (60 mg/kg). Periodontitis was induced via ligation method. Silk ligatures were placed at the mandibular right first molars. GSPE was administered by oral gavage. After 30 days, all rats were killed. Alveolar bone loss was measured morphometrically via a stereomicroscope. For histopathological analyses, Alizarin red staining, and matrix metalloproteinase (MMP)-8, vascular endothelial growth factor and hypoxia inducible factor (HIF)-1α immunohistochemistry were performed. Tartrate-resistant acid phosphatase-positive osteoclast cells and relative total inflammatory cells were also determined. RESULTS: The highest alveolar bone loss was observed in the D+P group (P < .05). GSP-200 group decreased alveolar bone loss (P < .05). The D+P group had the highest osteoclast counts, but the difference was not significant compared to the P, GSPE-100 and GSPE-200 groups (P > .05). The inflammation in the D+P group was also higher than the other groups (P < .05). The osteoblast numbers increased in the GSPE-100 and GSPE-200 groups compared to the P and D+P groups (P < .05). MMP-8 and HIF-1α levels were highest in the D+P group and GSPE significantly decreased these levels (P < .05). CONCLUSION: Within the limits of this animal study, it can be suggested that GSPE administration may decrease periodontal inflammation and alveolar bone loss via decreasing MMP-8 and HIF-1α levels and increase osteoblastic activity in diabetic rats with experimental periodontitis.

Micrometer-Sized Magnesium Whitlockite Crystals in Micropetrosis of Bisphosphonate-Exposed Human Alveolar Bone.

Osteocytes are contained within spaces called lacunae and play a central role in bone remodelling. Administered frequently to prevent osteoporotic fractures, antiresorptive agents such as bisphosphonates suppress osteocyte apoptosis and may be localized within osteocyte lacunae. Bisphosphonates also reduce osteoclast viability and thereby hinder the repair of damaged tissue. Osteocyte lacunae contribute to toughening mechanisms. Following osteocyte apoptosis, the lacunar space undergoes mineralization, termed "micropetrosis". Hypermineralized lacunae are believed to increase bone fragility. Using nanoanalytical electron microscopy with complementary spectroscopic and crystallographic experiments, postapoptotic mineralization of osteocyte lacunae in bisphosphonate-exposed human bone was investigated. We report an unprecedented presence of ∼80 nm to ∼3 µm wide, distinctly faceted, magnesium whitlockite [Ca18Mg2(HPO4)2(PO4)12] crystals and consequently altered local nanomechanical properties. These findings have broad implications on the role of therapeutic agents in driving biomineralization and shed new insights into a possible relationship between bisphosphonate exposure, availability of intracellular magnesium, and pathological calcification inside lacunae.

Hyaluronic Acid Versus Ultrasonic Resorbable Pin Fixation for Space Maintenance in Non-Grafted Sinus Lifting.

PURPOSE: An ultrasonic resorbable pin (SonicWeld, KLS Martin, Mühlheim, Germany) was compared with hyaluronic acid (Hyaloss Matrix, Anika Therapeutics, Bedford, MA) for their ability to maintain space in non-grafted sinus lifting. MATERIALS AND METHODS: A comparative split-mouth study was designed and implemented. Six women and 4 men were included (mean age, 56.7 yr). The primary predictors hyaluronic acid (HA) application and ultrasonic resorbable pin fixation (URPF) were coded as binary variables. The primary outcome variables were height of alveolar bone (HAB) and reduction in sinus volume (RSV). Secondary outcomes were bone density and implant survival. RESULTS: The postoperative mean HAB was significantly higher than the preoperative mean HAB on the 2 sides (P < .05). Mean increases in HAB and RSV on the URPF side were significantly greater than those on the HA side (P < .05). In total, patients were treated with 40 implants. No type I bone quality was identified; 14 (35%) implants were inserted in type II bone, 22 (50%) in type III bone, and 6 (15%) in type IV bone. There was no statistically meaningful difference between the 2 sides for implant survival or bone quality. At 6 months, all implants were clinically stable and the definitive prostheses were functional, resulting in a survival rate of 100%. CONCLUSIONS: There was sufficient bone height to eventually place implants on the 2 sides in all patients. The 2 techniques yielded predictable outcomes in implant survival and bone quality. However, HAB and RSV were considerably greater on the URPF side.

Therapeutic effects of systemic vitamin k2 and vitamin d3 on gingival inflammation and alveolar bone in rats with experimentally induced periodontitis.

BACKGROUND: The synergistic effects of vitamin D3 and vitamin K2 on bone loss prevention have been reported. This study evaluates the effects of vitamin D3 and vitamin K2 supplementation in conjunction with conventional periodontal therapy (scaling and root planing [SRP]) on gingival interleukin (IL)-1ß and IL-10, serum bone alkaline phosphatase (B-ALP) and tartrate-resistant acid phosphatase 5b (TRAP-5b), and calcium and alveolar bone levels in rats with experimentally induced periodontitis. METHODS: Seventy-two rats were divided into the following groups: 1) healthy; 2) periodontitis; 3) SRP; 4) SRP + vitamin D3; 5) SRP + vitamin K2; and 6) SRP + vitamins K2 and D3. Periodontitis was induced by ligature placement for 7 days, and vitamin K2 (30 mg/kg) and/or vitamin D3 (2 µg/kg) were administered for 10 days in the SRP + vitamin D3, SRP + vitamin K2, and SRP + vitamins K2 and D3 groups by oral gavage. On day 18, the animals were sacrificed, serum B-ALP, TRAP-5b, and calcium levels were measured, gingiva specimens were extracted for IL-1ß and IL-10 analysis, and distances between the cemento-enamel junction and alveolar bone crest were evaluated. RESULTS: Alveolar bone levels in the periodontitis group were significantly greater than those in the other five groups. No significant differences were found in gingival IL-1ß and IL-10, serum B-ALP and TRAP-5b, and calcium and alveolar bone levels between the groups receiving SRP and vitamins and the group receiving SRP alone. CONCLUSION: Within the limitations of this study, vitamin D3 and K2 alone or in combination did not affect gingival IL-1ß and IL-10, serum B-ALP and TRAP-5b levels, or alveolar bone compared with conventional periodontal therapy alone.

Alveolar bone regeneration in response to local application of calcitriol in vitamin D deficient rats.

AIM: Vitamin D deficiency is considered to diminish bone regeneration. Yet, raising the serum levels takes months. A topic application of the active vitamin D metabolite, calcitriol, may be an effective approach. Thus, it becomes important to know the effect of vitamin D deficiency and local application on alveolar bone regeneration. MATERIAL AND METHODS: Sixty rats were divided into three groups; two vitamin depletion groups and a control group. Identical single defects (2 mm diameter) were created in the maxilla and mandible treated with calcitriol soaked collagen in one deficiency group while in the other two groups not. Histomorphometric analysis and micro CTs were performed after 1 and 3 weeks. Serum levels of 25(OH)D3 and PTH were determined. RESULTS: Bone formation rate significantly increased within the observation period in all groups. Bone regeneration was higher in the maxilla than in the mandible. However, bone regeneration was lower in the control group compared to vitamin depletion groups, with no significant effects by local administration of calcitriol (micro CT mandible p = 0.003, maxilla p < 0.001; histomorphometry maxilla p = 0.035, mandible p = 0.18). CONCLUSION: Vitamin D deficiency not necessarily impairs bone regeneration in the rat jaw and a single local calcitriol application does not enhance healing.

Histological analysis of the periodontal ligament and alveolar bone during dental movement in diabetic rats subjected to low-level laser therapy.

OBJECTIVE: The purpose of this research was to evaluate the histological changes of the periodontal ligament and alveolar bone during dental movement in diabetic rats subjected to low level laser therapy (LLLT). METHODS: The movement of the upper molar was performed in 60 male Wistar rats divided into four groups (n=15): CTR (control), DBT (diabetic), CTR/LT (irradiated control) and DBT/LT (irradiated diabetic). Diabetes was induced with alloxan (150 mg/kg, i.p.). LLLT was applied with GaAlAs laser at 780 nm (35 J/cm(2)). After 7, 13 and 19 days, the periodontal ligament and alveolar bone were histologically analyzed. RESULTS: The mean of osteoblasts (p<0.01) and blood vessels (p<0.05) were significantly decreased in DBT compared with CTR at 7 days, whereas the mean of osteoclasts was lower at 7 (p<0.001) and 13 days (p<0.05). In DBT/LT, only the mean of osteoclasts was lower than in CTR (p<0.05) at 7 days, but no difference was observed at 13 and 19 days (p>0.05). The collagenization of the periodontal ligament was impaired in DBT, whereas DBT/LLT showed density/disposition of the collagen fibers similar to those observed in CTR. CONCLUSIONS: LLLT improved the periodontal ligament and alveolar bone remodeling activity in diabetic rats during dental movement.

Platelet-rich plasma, low-level laser therapy, or their combination promotes periodontal regeneration in fenestration defects: a preliminary in vivo study.

BACKGROUND: This study histomorphometrically analyzes the influence of platelet-rich plasma (PRP), low-level laser therapy (LLLT), or their combination on the healing of periodontal fenestration defects (PFDs) in rats. METHODS: PFDs were surgically created in the mandibles of 80 rats. The animals were randomly divided into four groups: 1) C (control) and 2) PRP, defects were filled with blood clot or PRP, respectively; 3) LLLT and 4) PRP/LLLT, defects received laser irradiation, were filled with blood clot or PRP, respectively, and then irradiated again. Animals were euthanized at either 10 or 30 days post-surgery. Percentage of new bone (NB), density of newly formed bone (DNB), new cementum (NC), and extension of remaining defect (ERD) were histomorphometrically evaluated. Data were statistically analyzed (analysis of variance; Tukey test, P <0.05). RESULTS: At 10 days, group PRP presented ERD significantly lower than group C. At 30 days, group PRP presented NB and DNB significantly greater than group C. Groups LLLT, PRP, and PRP/LLLT showed significant NC formation at 30 days, with collagen fibers inserted obliquely or perpendicularly to the root surface. NC formation was not observed in any group C specimen. CONCLUSIONS: LLLT, PRP, or their combination all promoted NC formation with a functional periodontal ligament. The combination PRP/LLLT did not show additional positive effects compared to the use of either therapy alone.

Alveolar bone regeneration potential of a traditional Chinese medicine, Bu-Shen-Gu-Chi-Wan, in experimental periodontitis.

BACKGROUND AND OBJECTIVE: The aim of this study was to investigate the effect of a traditional Chinese medicine, Bu-Shen-Gu-Chi-Wan, on experimental periodontitis and bone regeneration in rat. MATERIAL AND METHODS: Sixty female Sprague-Dawley rats were divided equally into three groups: a healthy control group (Group N); a periodontitis group (Group P); and the Bu-Shen-Gu-Chi-Wan treatment group (Group T). A 0.2-mm wire was placed around the maxillary first molar and Porphyromonas gingivalis was injected into the gingival sulcus. Rats in different groups were administered 0.9% normal saline or Bu-Shen-Gu-Chi-Wan solution (4 g/kg of body weight, for three alternate days), and the animals were killed after 4 wk. Morphological analysis of alveolar bone rebuilding was performed using micro-computed tomography (micro-CT) and stereomicroscopy, and the variation of inflammation in the periodontium was determined histologically. The serum levels of the proinflammatory cytokines interleukin-1beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) and of the bone-turnover biomarkers pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) and osteocalcin (OC) were determined using radioimmunoassays. RESULTS: After treatment with Bu-Shen-Gu-Chi-Wan, there were significant decreases in the levels of IL-1ß, TNF-α, ICTP and OC and decreased inflammatory infiltration in the periodontal tissues of Group T. significant changes in alveolar bone volume and density were detected by micro-CT, but stereomicroscopy did not detect a significant improvement of alveolar bone height. CONCLUSION: The data of the present study suggest that the traditional Chinese medicine, Bu-Shen-Gu-Chi-Wan, has anti-inflammatory function in experimental periodontitis and may simultaneously improve alveolar bone remodeling.

Oxytocin promotes bone formation during the alveolar healing process in old acyclic female rats.

OBJECTIVE: OT was reported to be a direct regulator of bone mass in young rodents, and this anabolic effect on bone is a peripheral action of OT. The goal of this study was to investigate the peripheral action of oxytocin (OT) in the alveolar healing process in old female rats. MATERIALS AND METHODS: Females Wistar rats (24-month-old) in permanent diestrus phase, received two ip (12h apart) injections of saline (NaCl 0.15M - control group) or OT (45µg/rat - treated group). Seven days later, the right maxillary incisor was extracted and analyses were performed up to 28 days of the alveolar healing process (35 days after saline or OT administration). RESULTS: Calcium and phosphorus plasma concentrations did not differ between the groups. The plasma biochemical bone formations markers, alkaline phosphatase (ALP) and osteocalcin were significantly higher in the treated group. Histomorphometric analyses confirmed bone formation as the treated group presented the highest mean value of post-extraction bone formation. Tartrate-resistant acid phosphatase (TRAP) was significantly reduced in the treated group indicating an anti-resorptive effect of OT. Immunohistochemistry reactions performed in order to identify the presence of osteocalcin and TRAP in the bone cells of the dental socket confirmed these outcomes. CONCLUSIONS: OT was found to promote bone formation and to inhibit bone resorption in old acyclic female rats during the alveolar healing process.

Regenerative wound healing in acute degree III mandibular defects in dogs.

OBJECTIVE: To evaluate the healing events in degree III furcation defects in dogs following the application of the combination of an enamel matrix derivative with a biphasic calcium phosphate (Emdogain Plus). METHOD AND MATERIALS: Seventeen degree III furcation defects, 5 mm high and 4 mm wide, were created in 9 dogs. In both groups, the defects were conditioned with EDTA. One defect was treated with Emdogain Plus (n = 9), while the contralateral defect serving as control remained empty (n = 8). The defects in both groups were fully covered by coronally repositioned flaps. After 5 months of healing, histologic and histometric analysis was preformed. RESULTS: A significant amount of new attachment and bone formation was observed in both control and test specimens. However, in a number of control specimens, ankylosis was also observed. In the control and test groups, respectively, the mean new cementum length was 10.8 ± 2.1 mm and 8.6 ± 3.2 mm; the mean periodontal ligament length was 7.6 ± 3.8 mm and 8.1 ± 4.0 mm. The mean new bone height was 4.4 ± 1.3 mm and 4.3 ± 1.6 mm in the control and test groups, respectively. No statistical differences were found between the two groups in terms of amount of cementum, periodontal ligament, and alveolar bone regeneration. CONCLUSION: The present study failed to show higher amounts of newly formed cementum and bone following treatment of acute degree III mandibular furcation defects following use of Emdogain Plus compared with a coronally advanced flap. Emdogain Plus seems to have a protective role against ankylosis in this type of defect.

Effect of laser phototherapy on the hyalinization following orthodontic tooth movement in rats.

OBJECTIVE: We aimed to assess histologic changes after the use of laser phototherapy (LPT) during induced tooth movement with 40 g/F on young adult male rats. BACKGROUND DATA: Hyalinization is a sterile necrosis at the pressure zone of the periodontal ligament observed during the initial stages of the orthodontic movement, and extensive hyaline areas might cause an important delay in the tooth movement. The use of LPT is considered an enhancement factor for bone repair, as it stimulates microcirculation as well as the cellular metabolism. MATERIALS AND METHODS: Thirty animals were divided into two groups (n=15), named according to the time of animal death (7, 13, and 19 days). Half of the animals in each group were subjected to irradiation with infrared (IR) laser (λ790 nm, round shaped beam, 40 mW, continuous wave (CW), diameter=2 mm (0.0314 cm(2)), 1.273 W/cm(2), time=2×112 sec+1×275 sec (total time 499 sec), 2×142.6/4.48 J+1×350/11 J, 635.2 J/cm(2)/20 J/ session), during orthodontic movement, the other half were used as nonirradiated controls. After animal death, specimens were sectioned, processed, and stained with hematoxylin and eosin (HE) and Sirius Red, and were used for semi-quantitative histologic analysis by light microscopy. Data were statistically analyzed. RESULTS: We demonstrated that LPT positively affected an important aspect of dental movement; the hyalinization. In the present study, we found a significant reduced expression of hyalinization after 19 days. On irradiated subjects, hyalinization was increased at day 7 with significant reduction at day 13. CONCLUSIONS: It is possible to conclude that the use of laser light caused histologic alterations during the orthodontic movement characterized by increased formation of areas of hyalinization at early stages, and late reduction when compared to nonirradiated animals.

A clinical and histomorphometric study of calcium sulfate compared with freeze-dried bone allograft for alveolar ridge preservation.

BACKGROUND: Many materials have been found to be effective in ridge preservation. The purpose of this study is to determine whether calcium sulfate (CS) is as effective as freeze-dried bone allograft (FDBA) in preserving postextraction ridge dimensions and to evaluate the amount of new bone formation and graft clearance through histologic analysis. METHODS: Thirty-one extraction sites were selected. Postextraction clinical measurements were made, and sites were divided randomly into the test group (CS) or the control group (FDBA). After graft placement, all individuals received the same postoperative treatment and instructions. Participants were recalled after 3 months, measurements were made, and sites were re-entered. Bone samples were harvested and analyzed with histologic methodology for new bone formation and remaining residual graft. RESULTS: Thirteen test and 15 control sites were evaluated. There was no significant change in vertical ridge height before or after surgery within the test and control groups (P = 0.57, P = 0.68, respectively). There was a significant decrease in bucco-lingual ridge width for both groups (P = 0.0003, P = 0.0075, respectively), but the difference between groups was not significant (P = 0.11). Histologic analysis revealed an average of 32% new bone formation with 2.5% graft remaining for the test group and 16.7% new bone formation with 21% graft remaining for the control. CONCLUSIONS: Results indicate that CS is as effective as FDBA in preserving postextraction ridge dimensions in non-molar extraction sites. There is greater clearance of CS with more new bone formation after ≈3 months compared with FDBA in these sites. This paper received the Maynard K. Hine Award for Excellence in Dental Research presented by the Indiana Section of the American Association for Dental Research and supported by Procter & Gamble.

Effects of traditional Chinese medicine on bone remodeling during orthodontic tooth movement.

ETHNOPHARMACOLOGICAL RELEVANCE: Dipsacus asper Wall (Dipsacaceae), Salvia miltiorrhiza (Salvia) and Drynaria fortunei (Drynaria) have been traditionally used in Chinese medicine as the main ingredient of many formulations for the treatment of cardiovascular and inflammatory diseases. AIM OF THE STUDY: This study was aimed to evaluate the effect of the traditional Chinese medicine (TCM) Dipsacaceae, Salvia and Drynaria on bone remodeling during orthodontic tooth movement (OTM). SETTING: This study was conducted in School of Stomatology, Shandong University between 2009 and 2010 [Jinan, Shandong, China]. MATERIALS AND METHODS: Ninety-six eight-week-old female SPF Wistar rats 180-200 g were selected and randomly divided into four groups of 24: Dipsacaceae group, Salvia group, Drynaria group and control group. Animal models for orthodontic tooth movement were then established which consisted of a closed coil spring ligated to the upper first molar and incisors, exerting a force of 40 g during the experimental period. Rats in the TCM groups were given Dipsacaceae, Salvia and Drynaria decoction respectively by intragastric administration 6 g/kg/day and the control group were given normal saline 3 ml. The rats were sacrificed in batch on the 7th, 14th, 21st and 28th days after orthodontic treatment. Slices from periodontium of the upper first molar were observed under optical microscope. Neovascularization, new bone formation and osteoclast number were observed. RESULTS: The upper first molars were drawn mesial by the force. Telangiectasia and new bone formation in periodontal tissue were significantly in the TCM groups compared with the control group. Application of orthodontic forces in the experimental teeth showed a significant increase (P<0.05) of osteoclast number in the TCM group when compared with the control group. In addition, the number of osteoclast had no significant differences among the TCM groups (P>0.05). Osteoclast number in the TCM group and the control group were 10.12±0.058, 10.13±0.022, 10.09±0.047 and 9.55±0.045, respectively. CONCLUSIONS: These findings suggest that the TCM decoction are beneficial to the alveolar bone remodeling by promoting osteoclast differentiation during OTM.