Implant Placement after Closure of Oroantral Communication by Sinus Bone Graft Using a Collagen Barrier Membrane in the Shape of a Pouch: A Case Report and Review of the Literature.

Oro-antral communication (OAC) acts as a pathway for bacteria between the maxillary sinus and oral cavity, and is a common complication after the removal of a dental implant or extraction of a tooth from the maxillary posterior area. In the case of an untreated OAC, oro-antral fistula develops and becomes epithelialized. We aimed to introduce a treatment for OAC closure via a sinus bone grafting procedure using bone tacks and a collagen membrane with an allograft. The procedure was performed by applying an absorbable membrane made in pouch form. This membrane acted as a barrier for closing the large sinus membrane perforation. Bone tacks were used to fix the membranes. Subsequently, the maxillary sinus was filled with the allograft, and the absorbable membrane was reapplied. Primary closure was achieved by performing a periosteum-releasing incision for a tension-free suture. After 6 months, sufficient bone dimensions were gained without any occurrence of maxillary sinusitis or recurrence of OAC. Additional bone grafts and implantation could be performed to rehabilitate the maxillary posterior area. We conclude that this technique might be a useful treatment for reconstructing the maxillary posterior area with simultaneous sinus bone graft and OAC closure.

Effects of dietary energy and crude protein levels on growth performance, blood profiles, and nutrient digestibility in weaning pigs.

OBJECTIVE: This experiment was conducted to investigate the effect of reducing dietary metabolic energy (ME) and crude protein (CP) levels on growth performance, blood profiles, and nutrient digestibility in weaning pigs. METHODS: A total of 240 crossbred pigs (Duroc×[Landrace×Yorkshire]) with an average body weight of 8.67±1.13 kg were used for a 6-week feeding trial. Experimental pigs were allotted to a 2×3 factorial arrangement using a randomized complete block design. The first factor was two levels of dietary ME density (low ME level, 13.40 MJ/kg or high ME level, 13.82 MJ/kg) and the second factor was three dietary CP levels based on subdivision of early and late weaning phases (low CP level, 19.7%/16.9%; middle CP level, 21.7%/18.9%; or high CP level, 23.7%/20.9%). RESULTS: Over the entire experimental period, there were no significant difference in body weight among groups, but a decrease in diet energy level was associated with an increase in average daily feed intake (p = 0.02) and decrease in gain-feed ratio (G:F) ratio (p<0.01). Decreased CP levels in the diet were associated with a linear increase in average daily gain (p< 0.05) and quadratic increase in G:F ratio (p<0.05). In the early weaning period, blood urea nitrogen concentration tended to increase when ME in the diet decreased and decrease when CP level in the diet decreased (p = 0.09, p<0.01, respectively). Total protein concentration tended to increase when CP level was reduced (p = 0.08). In the late weaning period, blood urea nitrogen concentration decreased linearly as CP level decreased (p<0.01). The CP and crude fat digestibility decreased when ME was decreased by 0.42 MJ/kg (p = 0.05, p = 0.01, respectively). The CP digestibility increased linearly as CP level decreased (p = 0.01). CONCLUSION: A weaning pig diet containing high ME level (13.82 MJ/kg) and low CP level (19.7%/16.9%) can improve pig growth performance and nutrient digestibility.

Effects of wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs.

OBJECTIVE: This study was conducted to evaluate various wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs. METHODS: A total of 120 growing pigs ([Yorkshire×Landrace]×Duroc), with an average 27.75± 1.319 kg body weight, were used in growth trial. Pigs were allotted into each treatment by body weight and sex in 4 replicates with 6 pigs per pen in a randomized complete block design. Four-phase feeding programs were used in this experiment. The treatments included the following: i) corn-soybean meal (SBM) - based diet (CON), ii) corn-SBM - based diet+15% of wheat (W15), iii) corn-SBM - based diet+30% of wheat (W30), iv) corn-SBM - based diet+45% of wheat (W45), and 5) corn-SBM-based diet+60% of wheat (W60). RESULTS: There was no significant difference in growth performance among the dietary treatments. However, the gain-to-feed (G:F) ratio tended to increase (quadratic, p<0.08) when the pigs were fed a higher wheat diet during the finishing period. The digestibility of crude ash and fat tended to decrease as the wheat supplementation level increased (p<0.08). The proximate analysis of the longissimus muscle was not affected by the dietary level of wheat. The crude ash content in pork was decreased linearly as the wheat supplementation level increased (p = 0.05). There was no significant difference in the pH level, shear force, water holding capacity, and cooking loss of the pork. In pork and fat, L*, a*, and b* values were not significantly different among dietary treatments. CONCLUSION: Wheat can be supplemented up to 60% in a growing-finishing pig without detrimental effects on growth and pork quality. The G:F ratio tended to improve in the finishing period by wheat inclusion.

Six Month Clinical Evaluation of Interdental Papilla Reconstruction with Injectable Hyaluronic Acid Gel Using an Image Analysis System.

PURPOSE: Obtaining predictable and aesthetically pleasing interdental papilla is challenging in dental reconstruction. Hyaluronic acid gel has been successfully used to reduce facial creases and similar abnormalities. The purpose of this study was to clinically assess the efficiency of interdental papilla reconstruction with injectable hyaluronic acid gel. MATERIALS AND METHODS: Ten patients with 43 treated sites in the maxillary anterior region were studied. Photographic standardization devices were designed for image analysis before treatment. This treatment was repeated up to five times during 3-week intervals. Patients were followed 6 months after initial gel application. RESULTS: Twenty-nine sites had complete papilla reconstruction and 14 sites improved from 39 to 96% of interdental papilla reconstruction rate. Complete interdental papilla reconstruction was performed when black triangle at initial examination had area of ≤0.25 mm(2) , height of ≤1mm, or width of ≤0.5mm. CONCLUSION: Injectable hyaluronic acid gel may be a promising treatment for enhancing papillary esthetics. CLINICAL SIGNIFICANCE: Interdental papilla reconstruction with injectable hyaluronic acid gel can be suggested as a minimally invasive treatment option for interdental papilla deficiencies in small areas. However, long-term results of this treatment beyond 6 months are not yet known. (J Esthet Restor Dent 28:221-230, 2016).

Sinus floor augmentation using mineralized freeze-dried bone allograft combined with recombinant human bone morphogenetic protein-2 (rhBMP-2): A long-term retrospective study.

Background/purpose: The combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a carrier material has not been extensively studied. This study aimed to evaluate the clinical, radiological, and histomorphometric outcomes of sinus floor augmentation using a 3:7 mixture of cancellous and cortical freeze-dried bone allografts (mixed AG) combined with rhBMP-2. Materials and methods: Mixed AG was used for sinus floor augmentation in a total of 21 patients with a residual alveolar bone height <5 mm. Among the total 47 sites, augmentation with and without rhBMP-2 was performed in 26 and 21 sites, respectively. Radiographic parameters were assessed using cone-beam computed tomography. After a six-month healing period, core biopsies were harvested for histomorphometric analysis. Results: The bone gain after healing was 13.36 ± 3.9 mm and 12.07 ± 3.8 mm in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively. The survival rate of implants in both groups was 100% during the follow-up period. The proportion of newly formed bone was 24.6 ± 10.2% and 39.7 ± 18.3% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Moreover, the percentage of residual graft material was 21.0 ± 12.2% and 9.6 ± 10.0% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Conclusion: Mixed AG combined with rhBMP-2 could be a suitable material for sinus floor augmentation. This combination may reduce the treatment time and improve the predictability of implant placement.

Anticancer activity of Saussurea lappa extract by apoptotic pathway in KB human oral cancer cells.

CONTEXT: Saussurea lappa Dence (Compositae) is used as a traditional herbal medicine to treat abdominal pain and tenesmus in East Asia. Current studies have shown that S. lappa has anticancer activity in divergent of cancer cells. However, the effects of S. lappa on oral cancer and its mechanisms of action have yet to be elucidated. OBJECTIVE: To explore its potential chemotherapeutic effects and mechanism of cell growth inhibition on human oral cancer cells. MATERIALS AND METHODS: The dried roots of S. lappa were used in this study. Cell viability of KB cells was evaluated by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay after treatment with 30 µg/ml of methanol extract from the dried roots of S. lappa. To understand whether its effect on cell death is related with apoptosis pathway, we performed DNA fragmentation assay, western blot, caspase activity assay and fluorescence-activated cell sorting (FACS) analysis. RESULTS: Treatment of S. lappa extract onto KB cells reduced cell viability significantly with an IC50 value of 30 µg/ml. The formation of a DNA ladder was observed starting at the 24 h treatment. In western blotting analysis, the S. lappa extract induced the proteolytic processing of caspase-3, -9 and poly (ADP-ribose) polymerase, a significant increase of Bax and marked reduction of Bcl-2. We also confirmed the activation of caspase-3/-7 in living KB cells by fluorescence microscopy. CONCLUSION: These results suggested that S. lappa extract inhibited cell proliferation through the apoptosis pathway in KB human oral cancer cells.

A retrospective comparison of 3 approaches of vestibuloplasty around mandibular molar implants: apically positioned flap versus free gingival graft versus modified periosteal fenestration.

PURPOSE: This study aimed to clinically evaluate the efficacy of vestibuloplasty around lower molar implants using 3 different modalities: apically positioned flap alone (APF), APF with a free gingival graft (FGG), and APF with modified periosteal fenestration (mPF). METHODS: Three different vestibuloplasty procedures during second-stage implant surgery were performed at the mandibular molar area in 61 patients with a shallow vestibule and insufficient keratinized tissue (KT). The clinical measurements of KT width were recorded at baseline, immediately after surgery (T0), 6 months after surgery (T6), and 12 months after surgery (T12). Soft tissue esthetic scores were measured. RESULTS: An additional KT width gain from baseline to T12 of approximately 2 mm was obtained with FGG and mPF compared to that with APF. Shrinkage of the re-established tissue was lower with mPF and FGG than with APF, whereas the esthetic profile was better with APF and mPF than with FGG. CONCLUSIONS: Within the limitations of this study, mPF showed potential as a promising approach for vestibuloplasty around the lower molar implants compared to the traditional APF and FGG.

Application of rpoB and zinc protease gene for use in molecular discrimination of Fusobacterium nucleatum subspecies.

Fusobacterium nucleatum is classified into five subspecies that inhabit the human oral cavity (F. nucleatum subsp. nucleatum, F. nucleatum subsp. polymorphum, F. nucleatum subsp. fusiforme, F. nucleatum subsp. vincentii, and F. nucleatum subsp. animalis) based on several phenotypic characteristics and DNA-DNA hybridization patterns. However, the methods for detecting or discriminating the clinical isolates of F. nucleatum at the subspecies levels are laborious, expensive, and time-consuming. Therefore, in this study, the nucleotide sequences of the RNA polymerase beta-subunit gene (rpoB) and zinc protease gene were analyzed to discriminate the subspecies of F. nucleatum. The partial sequences of rpoB (approximately 2,419 bp), the zinc protease gene (878 bp), and 16S rRNA genes (approximately 1,500 bp) of the type strains of five subspecies, 28 clinical isolates of F. nucleatum, and 10 strains of F. periodonticum (as a control group) were determined and analyzed. The phylogenetic data showed that the rpoB and zinc protease gene sequences clearly delineated the subspecies of F. nucleatum and provided higher resolution than the 16S rRNA gene sequences in this respect. According to the phylogenetic analysis of rpoB and the zinc protease gene, F. nucleatum subsp. vincentii and F. nucleatum subsp. fusiforme might be classified into a single subspecies. Five clinical isolates could be delineated as a new subspecies of F. nucleatum. The results suggest that rpoB and the zinc protease gene are efficient targets for the discrimination and taxonomic analysis of the subspecies of F. nucleatum.

Comparative study between resorbable and nonresorbable plates in orthognathic surgery.

PURPOSE: The purpose of the present study was to evaluate the clinical application of resorbable and nonresorbable plates for correction of facial asymmetry. PATIENTS AND METHODS: A total of 272 patients who had undergone orthognathic surgery were enrolled. The site of osteotomy was fixed using a nonresorbable plate in group I (n = 152) and using a resorbable plate in group II (n = 120). The postoperative complications included postoperative anterior open bite, infection, temporomandibular joint dysfunction, and postoperative relapse. The incidence of all complications was examined. RESULTS: The surgical outcome was successful in 269 patients (98.89%). Of the 152 patients with a titanium plate, 13 (8.6%) developed complications. Of the 120 patients with a resorbable plate, 22 (18.3%) developed complications. A greater degree of postoperative open bite and a trend toward relapse were observed in patients' cases in which an absorbable fixation plate was used. Postoperative infection occurred in patients with an absorbable fixation plate. CONCLUSION: On the basis of these data, we have concluded that an absorbable fixation plate should be used instead of a titanium fixation plate in indicated patients.

Technical Note on Root Coverage of Lower Anterior Teeth Using a Partially Deepithelialized Connective Tissue Graft (PE-CTG) Aided by a High-Speed Handpiece.

Root coverage in the mandibular anterior region is challenging because of a thin gingival biotype, shallow vestibule, and high frenum attachment. Several methods have been introduced to predict the root coverage in this area. Stimmelmayr proposed a method of performing root coverage using a combination epithelialized-subepithelial connective tissue graft (CTG). However, it is difficult to precisely acquire connective tissue according to this method. Therefore, in this case report, we would like to introduce a technique to harvest a partially deepithelialized CTG (PE-CTG) aided by a high-speed handpiece, which helps in procuring the graft easily and quickly. This method could lower the patient's morbidity at donor sites and enhance the healing process. Additionally, it could increase the amount of keratinized gingiva in the mandibular anterior region without reducing the vestibular depth. Therefore, PE-CTG using a high-speed handpiece can be a promising treatment option for the root coverage of the mandibular anterior teeth.

Sinus floor augmentation using mixture of mineralized cortical bone and cancellous bone allografts: Radiographic and histomorphometric evaluation.

BACKGROUND/PURPOSE: Due to the pneumatization of the maxillary sinus, the sinus floor augmentation is often performed to implant placement in the maxillary posterior region. The aim was to perform radiographic and histomorphometric evaluation after placement of mixed allografts (cortical freeze-dried bone allograft [FDBA] 50%:cancellous FDBA 50%) during sinus floor augmentation. MATERIALS AND METHODS: In 37 patients, anorganic bovine bone (ABB, sites = 16), mineralized cancellous bone allograft (MCBA, sites = 15), and mixed allografts (Mixed AG, sites = 20) were placed during sinus floor elevation via the lateral approach (LSFE), at total 51 sites with residual alveolar bone height (RBH) < 5 mm. Cone-beam computed tomography images were obtained before LSFE (T0), after surgery (T1), and 6 months after surgery (T2) for radiographic analysis. After a 6-month healing period, core biopsies were harvested and histomorphometric analysis was performed. RESULTS: The mean augmented bone height (ABH) of ABB, MCBA, and mixed AG groups after surgery was similar (13.86 ±â€¯4.19 mm, 13.99 ±â€¯4.07 mm, and 14.20 ±â€¯3.12 mm, respectively; P > 0.05). The mean ABH of ABB, MCBA, and mixed AG groups after 6 months was similar (13.72 ±â€¯4.55 mm, 11.83 ±â€¯3.31 mm, and 12.53 ±â€¯2.97 mm, respectively; P > 0.05). In the ABB, MCBA, and mixed AG groups, the proportion of newly formed bone (NB) was similar (36.13 ±â€¯10.01%, 39.26 ±â€¯10.72%, and 31.27 ±â€¯18.31%, respectively; P > 0.05). CONCLUSION: This result demonstrated that mixed AG led to sufficient bone augmentation and histologically comparable NB formation as compared to ABB and MCBA for sinus floor augmentation.

Sample infection control needs assessment survey data from eight countries.

OBJECTIVES: To compare knowledge, attitudes and practice of standard methods in infection control by dentists in eight countries using a standardised questionnaire. METHODS: Self-administered questionnaires on dental infection control and safety (IC&S) knowledge, attitudes and practice were distributed to a convenience sample of dentists in India, Pakistan, Thailand, Philippines, Taiwan, China, South Korea and the United States of America. RESULTS: Knowledge and practice of infection control among the Asian dentists lagged behind the levels of US dentists. Availability and affordability of equipment and materials were some of the reasons for the practice of infection control and safety. Attitude towards universal/standard precautions in controlling bloodborne pathogens was comparable between groups surveyed. Tested knowledge and practice of infection control was acceptable but the attitude and understanding of universal/standard precautions was ambiguous among both Asian and USA dental practitioners. Education in dental infection control should focus on improving the attitudes of practitioners towards universal precautions. CONCLUSIONS: Knowledge and practice of dental IC&S was high among the USA respondents. Immunisation and IC & S should be stressed in Asia. Information obtained through this study could be used to plan and implement policies in improving dental infection control and occupational safety in individual countries.

Novel Use of Silicone Sheets for Immediate Implant Placement in Fresh Molar Extraction Sockets.

In the recent years, the immediate placement of dental implants into fresh extraction sites has become an acceptable treatment approach. However, immediate molar implant placement presents specific challenges because of the anatomical and physiologic limitations. Such implant surgeries commonly require procedures that use a barrier membrane to generate bone and soft tissue or one that seals the molar extraction socket through a coronally advanced flap. Here, as an alternative, we report a method for treating molar extraction socket wounds in the hard and soft tissues after immediate placement of an implant using a silicone sheet.

Effects of dietary energy and crude protein levels on growth performance, blood profiles, and carcass traits in growing-finishing pigs.

This experiment was conducted to evaluate the effect of dietary energy and crude protein (CP) levels on growth performance, blood profiles, and carcass traits in growing-finishing pigs. A total of 180 crossbred pigs ([Yorkshire × Landrace] × Duroc) with an average body weight of 30.96 ± 3.068 kg were used for a 12-week feeding trial. Experimental pigs were allotted to a 2 × 3 factorial arrangement using a randomized complete block (RCB) design. The first factor was two levels of dietary metabolizable energy (ME) density (13.40 MJ/kg or 13.82 MJ/kg), and the second factor was three dietary CP levels based on subdivision of growing-finishing phases (high: 18%/16.3%/16.3%/13.2% middle: 17%/15.3%/15.3%/12.2% and low: 16%/14.3%/14.3%/11.2%). Average daily gain (ADG) and gain-feed ratio (G:F ratio) decreased as dietary CP level was decreased linearly (linear, p < 0.05; p < 0.05, respectively) in the early growing period, and G:F ration also decreased as dietary CP level was decreased linearly (linearly, p < 0.05) over the whole growing phase. Over the entire experimental period, G:F ratio decreased as dietary ME level decreased (p = 0.01). Blood urea nitrogen (BUN) concentration was increased as dietary energy level decreased in growing period (p < 0.01). During finishing period, total protein concentration was decreased by lower dietary energy level (p < 0.05). In this study, there were no significant differences in proximate factors, physiochemical properties, muscle TBARS assay results, pH changes, or color of pork by dietary treatments. However, saturated fatty acid (SFA) increased (p < 0.01) and polyunsaturated fatty acid (PUFA) decreased (p < 0.05) when ME was decreased by 0.42 MJ/kg in growing-finishing pig diets. In addition, monounsaturated fatty acid (MUFA) tended to increase when CP level was decreased in growing-finishing pig diets (p = 0.06). A growing-finishing diet of 13.82 MJ/kg diet of ME with the high CP level can improve growth performance and show better fatty acids composition of pork.

Cordyceps militaris induces the IL-18 expression via its promoter activation for IFN-gamma production.

ETHNOPHARMACOLOGICAL RELEVANCE: Cordyceps militaris, one of traditional herbal ingredient in oriental medicine, has been known to promote anticancer and immunomodulatory activities in vitro and in vivo. However, the biological mechanism of anticancer activity has been unknown. OBJECTIVE: To investigate the effect of Cordyceps militaris extract on expression of interferon gamma (IFN-gamma) through interlukin-18 (IL-18) induction and its biological mechanism in vitro and in vivo. MATERIALS AND METHODS: Mice were administrated orally with solution extracted from Cordyceps militaris. The transcription level of IL-18 and IFN-gamma production were measured by reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry. RAW 264.7 cells were transiently transfected with pCATp1 and pCATp2 for IL-18 promoter functional analysis. RESULTS: Cordyceps militaris extracts treatment significantly induced level of IL-18 transcription in mouse brain and liver and enhanced IL-18 transcription level and activated the IFN-gamma production in RAW 264.7 cells. Furthermore, Cordyceps militaris extract led to increase the activity of pCATp1 construct containing the 5' franking region of IL-18 promoter in RAW 264.7 cells. CONCLUSION: Cordyceps militaris extract induced IL-18 mRNA level via enhancing of P1 promoter region result in activation of IFN-gamma production, indicating its potential as an immune activator or anticancer drug.

Effects of 1,25-dihydroxyvitamin D3 on the differentiation of MC3T3-E1 osteoblast-like cells.

PURPOSE: The purpose of this study was to evaluate the effects of 1,25-dihydroxyvitamin D3 on the proliferation, differentiation, and matrix mineralization of MC3T3-E1 osteoblast-like cells in vitro. METHODS: MC3T3-E1 osteoblastic cells and 1,25-dihydroxyvitamin D3 were prepared. Cytotoxic effects and osteogenic differentiation were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S staining, and reverse transcription-polymerase chain reaction (RT-PCR) for osteogenic differentiation markers such as ALP, collagen type I (Col-I), osteocalcin (OCN), vitamin D receptor (VDR), and glyceraldehyde 3-phosphate dehydrogenase. RESULTS: The MTT assay showed that 1,25-dihydroxyvitamin D3 did not inhibit cell growth and that the rate of cell proliferation was higher than in the positive control group at all concentrations. ALP activity was also higher than in the positive control group at low concentrations of 1,25-dihydroxyvitamin D3 (10-10, 10-12, and 10-14 M). RT-PCR showed that the gene expression levels of ALP, Col-I, OCN, and vitamin D receptor (VDR) were higher at a low concentration of 1,25-dihydroxyvitamin D3 (10-12 M). Alizarin red S staining after treatment with 1,25-dihydroxyvitamin D3 (10-12 M) showed no significant differences in the overall degree of calcification. In contrast to the positive control group, formation of bone nodules was induced in the early stages of cell differentiation. CONCLUSIONS: We suggest that 1,25-dihydroxyvitamin D3 positively affects cell differentiation and matrix mineralization. Therefore, it may function as a stimulating factor in osteoblastic bone formation and can be used as an additive in bone regeneration treatment.

Effect of preameloblast-conditioned medium and CPNE7 on root surfaces in dogs: a histologic and histomorphometric evaluation.

Preameloblast-conditioned medium (PACM) has been reported as a potent dentin regenerative material, but its effects as a mixture on periodontal regeneration and the role of CPNE7 in PACM are not known. The purpose of this study is to evaluate the histologic and histomorphometric effects of preameloblast-conditioned medium (PACM) and CPNE7 on periodontal tissue healing in dogs. Seventy-two mandibular premolar roots from ten dogs were extracted and randomly divided into six groups (n = 12 each): (1) positive control group; (2) negative control group; (3) cementum-removed and PACM-treated group; (4) cementum-preserved and PACM-treated group; (5) CPNE7-inactivated PACM-treated group; and (6) recombinant CPNE7-treated group. The extracted roots were replanted into extraction sockets for 4 and 8 weeks and analyzed histologically. Most of the root surfaces in the negative control group showed ankylosis; and those in the experimental groups showed newly formed PDL-like and cementum-like tissues. Histomorphometric analysis of horizontal sections showed that the mean length of the PDL on the roots of the positive controls was similar to those in cementum-removed or -preserved and PACM-treated group at 8 weeks (p = 1.08). Sagittal sections showed that the mean length of the new cementum on the roots in cementum-removed and PACM-treated group was significantly greater than that in CPNE7-inactivated PACM-treated group (p = 0.037). The mean length of the newly formed PDL on the roots in CPNE7- inactivated PACM-treated and rCPNE7-treated groups was significantly greater than that in the negative controls at 8 weeks (p = 0.037, p = 0.036). The use of PACM and CPNE7 in tooth replantation resulted in increased PDL and cementum formation, suggesting the beneficial role of PACM and CPNE7 in periodontal tissue healing.

Effects of platelet-rich plasma on tooth replantation in dogs: a histologic and histomorphometric analysis.

PURPOSE: The purpose of this study was to evaluate the effects of platelet-rich plasma (PRP) on periodontal healing of replanted root surfaces in dogs histologically and histomorphometrically. METHODS: A total of 36 roots of mandibular incisors and premolars from 6 mongrel dogs were used. The roots were randomly divided into 3 groups: 1) a positive control group (n=12), in which the periodontal ligament (PDL) and cementum were retained and the roots were soaked in saline; 2) a negative control group (n=12), in which the PDL and cementum were removed and the roots were soaked in saline; and 3) an experimental group (n=12), in which the PDL and cementum were removed and the roots were soaked in PRP. After soaking the root surfaces, the extracted roots were replanted into the extraction sockets. The roots were covered using a coronally repositioned flap. RESULTS: Histologically, irregular-thickness PDL-like and cementum-like tissues were observed in the 4-week experimental group and the positive control group. PDL-like tissue and cementum-like tissue with a more uniform thickness were observed at 8 weeks. In the negative control group, PDL-like tissue and cementum-like tissue were rarely found, and root resorption and ankylosis were observed. In the cross-sectional histomorphometric analysis, the experimental group demonstrated a higher rate of formation of cementum-like tissue and a lower tooth ankylosis rate than the positive and negative control groups at 4 and 8 weeks. Although there was a significant difference in the tooth ankylosis rate and the formation of cementum-like tissue across the 3 groups (P<0.05), no statistical significance was observed between any pair of groups (P>0.017). CONCLUSIONS: Applying PRP to root surfaces during tooth replantation in dogs can reduce tooth ankylosis and increase PDL-like and cementum-like tissue formation.

The effects of interproximal distance between roots on the existence of interdental papillae according to the distance from the contact point to the alveolar crest.

BACKGROUND: This study investigated the existence of interdental papillae at certain distances from the contact point to the alveolar crest, depending on the interproximal distance between roots. METHODS: A total of 206 papillae from 80 patients were examined after the inflammation of the papillae had been minimized using non-surgical periodontal therapy. The existence of the interdental papillae was determined using the following categorization: 1) papillae were deemed to be absent if they did not extend all the way up to the contact point between the teeth; and 2) papillae were determined to be present if they filled up to the entire proximal space. The interproximal distance between roots and the distance from the contact point to the alveolar crest were measured when a full-thickness flap was used. The number of papillae present interproximally between roots, according to the distance from the contact point to the alveolar crest, was analyzed using the x2 analysis method, and the linear-by-linear association analysis method was used for trend analysis. RESULTS: The number of papillae that filled the interproximal space decreased with increasing distance from the contact point to the alveolar crest (P <0.05). In addition, the number of papillae that filled the interproximal space decreased with increasing interproximal distance between roots (P <0.05) and became more prominently decreasing with the increasing distance from the contact point to the alveolar crest (especially 4, 5, and 6 mm) (P <0.05). CONCLUSION: The results suggest that the interproximal distance between roots and the distance between the contact point and the alveolar crest have an independent and combined effect on the existence of interproximal papillae.

The association between radiographic embrasure morphology and interdental papilla reconstruction using injectable hyaluronic acid gel.

PURPOSE: The purpose of this study was to evaluate the clinical efficacy of enhancing deficient interdental papilla with hyaluronic acid gel injection by assessing the radiographic anatomical factors affecting the reconstruction of the interdental papilla. METHODS: Fifty-seven treated sites from 13 patients (6 males and 7 females) were included. Patients had papillary deficiency in the upper anterior area. Prior to treatment, photographic and periapical radiographic standardization devices were designed for each patient. A 30-gauge needle was used with an injection-assistance device to inject a hyaluronic acid gel to the involved papilla. This treatment was repeated up to 5 times every 3 weeks. Patients were followed up for 6 months after the initial gel application. Clinical photographic measurements of the black triangle area (BTA), height (BTH), and width (BTW) and periapical radiographic measurements of the contact point and the bone crest (CP-BC) and the interproximal distance between roots (IDR) were undertaken using computer software. The interdental papilla reconstruction rate (IPRR) was calculated to determine the percentage change of BTA between the initial and final examination and the association between radiographic factors and the reconstruction of the interdental papilla by means of injectable hyaluronic acid gel were evaluated. RESULTS: All sites showed improvement between treatment examinations. Thirty-six sites had complete interdental papilla reconstruction and 21 sites showed improvement ranging from 19% to 96%. The CP-BC correlated with the IPRR. More specifically, when the CP-BC reached 6 mm, virtually complete interdental papilla reconstruction via injectable hyaluronic acid gel was achieved. CONCLUSIONS: These results suggest that the CP-BC is closely related to the efficacy of hyaluronic acid gel injection for interdental papilla reconstruction.