Interradicular Bone Research Articles

Correlative Assessment of Interdental and Interradicular Bone Loss in Horizontal and Vertical Bone Defects In Chronic Periodontitis: A Clinical and Radiographic Study

It is important to treat periodontitis before involvement of furcation areas because of their complex anatomy and difficulty of access. Literature confirms that it is difficult to accurately determine the relationship of the amount of bone loss in the interdental areas associated with the interradicular areas and correlate them with the clinical periodontal status. The aim of this study was therefore to assess the existence of such an association, if any, in subjects with chronic periodontitis. The threshold of alveolar bone loss associated with progression of periodontal destruction and involvement of interradicular areas of the furcations is not clearly defined in the literature. The aim of this study was to investigate a correlation, if any between interdental and interradicular bone loss and clinical parameters in patients with chronic periodontitis. Periapical (IOPA) radiographs of mandibular molars were obtained from 193 sites in 33 males and 21 females between the age group of 25 and 55 years having chronic periodontitis. These were then scanned and digital measurement of linear distances was performed using dicom software of height and width of defect (horizontal and vertical), bone defect angle and interradicular bone loss. These measurements were correlated to pocket depth (PD) and clinical attachment loss (CAL) using One-way ANOVA followed by Tukeys HSD post hoc tests. Bone height significantly correlated with probing depth and CAL in horizontal defects (p<0.005) with hardly any furcation involvement (1.55%)whereas both bone height and width showed significant correlation with probing depth and CAL in vertical defects(P<0.001) with nearly 77% of sites showing furcation defects. A strong correlation of clinical parameters with bone defect dimensions suggests that early diagnosis and management of interdental bone loss may be critical to prevent furcation involvement.

Digital customized abutment planned before implant surgery: merging SS, 1A1T, Surgical stent, Prf an immediate crown on upper molar: A 4-year follow-up study

The goal of the present study was to introduce a new entirely in-house technique, based on digital patient data, used to create customized abutment and temporary crown, according to the anatomical limits and virtual position of the implant. The entire design and production took place before the surgery time and was based on both digital accuracy and biologic healing pattern promoted by Socket Shield (SS). The surgical phase consisted of replicating the digital project by inserting the implant in same position with accuracy. The Dicom file from CBCT and the intraoral scanner.Stl files were combined to collect all specific data and measurements in order to create models of the abutment and crown. A good-quality surgical stent was implemented, centering the osteotomy on the inter-radicular bone septum, in order to allow optimal primary stability and to provide reference points for accuracy during implant insertion. The implant with suitable threads configuration and connection quality was inserted with a manual check, replicating the virtual planning of the implant and allowing the immediate mount of the abutment (one abutment one time (1A1T)) and a provisional crown, made in advance. The post-extraction spaces were filled with Prf. A digital copy of the initial crown, in lithium disilicate, was then cemented after 6 months. The SS, which included both vestibular and palatal laminae prevented the known phenomenon of tissue remodeling in the post-extraction phase. The gingival tissue matured favorably around the abutment, inserted in the surgical phase and never removed (1A1T) with the recovery of the gingival recession on the mesial root, also thanks to the contribution of the Prf. The clinical result was stable initially and over time, with a 4-year follow-up. This is a proof of principle case report: the possibility offered by the digital technology to collect true anatomical data, to be used on a difficult area such as the molar maxillae. Skills are required both on the digital planning side (including the valuation of biological data) and on the surgical sessions, and demanding in terms of the range of accuracy required for correct implant position. The introduction of dynamic guided implantology could simplify tremendously the procedure. Initial diagnosis, correct planning, and surgical approach are the key factors for immediate and long-term results.

Assessment of Maxillary Molars Interradicular Septum Morphological Characteristics as Criteria for Ideal Immediate Implant Placement-The Advantages of Cone Beam Computed Tomography Analysis.

The aim of this study was to evaluate the interradicular septum bone morphometric characteristics using cone beam computed tomography (CBCT) images, as well as to establish quantitative shortcuts to allow clinicians to make a faster and more reliable plan for immediate implant placement in the maxillary molars area. This retrospective quantitative study was conducted on CBCT images obtained from 100 patients. The morphometric analysis of the maxillary molars region was based on the parameters obtained on the sagittal and axial slices. The analysis performed on sagittal slices showed that the first maxillary molars had a wider interradicular septum when compared to the second molars, but the septum height in the first molars was significantly below the height in the second maxillary molars. The axial CBCT slices analysis showed that both interradicular septum perimeter and surface area were significantly more pronounced in the first than in the second maxillary molars. The interradicular furcation angle significantly correlated with the surface area (positively) and septum height (negatively) for both molars. The results of this study may recommend CBCT image analysis as a useful tool in predefining the circumstances that can allow for substantially better planning of immediate implant placement procedures in the region of maxillary molars.

Efficacy of biocompatible trilayers nanofibrous scaffold with/without allogeneic adipose-derived stem cells on class II furcation defects of dogs' model.

This study aimed to evaluate the regenerative capacity of a newly-developed polycaprolactone (PCL)-based nanofibrous composite scaffold either alone or in combination with adipose-derived mesenchymal stem cells (ADSCs) as a treatment modality for class II furcation defects. After ADSCs isolation and scaffold characterization, the mandibular premolars of adult male mongrel dogs were selected and randomly assigned into three equal groups. In group I, class II furcation defects were surgically induced to the inter-radicular bone. While class II furcation defects of group II were induced as in group I. In addition, the defects were filled with the prefabricated scaffold. Moreover, class II furcation defects of group III were induced as in group II and instead the defects were filled with the prefabricated scaffold seeded with ADSCs. The dogs were sacrificed at 30days or at 60days. Periodontal wound healing/regeneration was evaluated by radiological examination using cone beam computed tomography and histologically using ordinary, histochemical, and immunohistochemical staining. In the two examination periods, group II defects compared to group I, and group III compared to the other groups showed a decrease in defect dimensions radiographically. Histologically, histochemically, and immunohistochemically, they significantly demonstrated better periodontal wound healing/regeneration, predominant collagen type I of newly formed bone and periodontal ligament with a significant increase in the immunoreactivity of vascular endothelial growth factor and osteopontin. The newly fabricated nanofibrous scaffold has enhanced periodontal wound healing/regeneration of class II furcation defects with further enhancement achieved when ADSCs seeded onto the scaffold before implantation. The implementation of our newly-developed PCL-based nanofibrous composite scaffolds in class II furcation defect either alone or in conjunction with ADSCs can be considered as a suitable treatment modality to allow periodontal tissues regeneration.

Interradicular distance and alveolar bone thickness for miniscrew insertion: a CBCT study of Persian adults with different sagittal skeletal patterns

BackgroundThis study aimed to assess the interradicular distance and alveolar bone thickness of Persian adults with different sagittal skeletal patterns for miniscrew insertion using cone-beam computed tomography (CBCT).MethodsThis cross-sectional study was conducted on maxillary and mandibular CBCT scans of 60 patients (18–35 years) in three groups (n = 20) of class I, II and III sagittal skeletal pattern. Anatomical and skeletal parameters were measured at 2, 4 and 6 mm apical to the cementoenamel junction (CEJ) by one examiner. The intra- and inter-class correlation coefficients were calculated to assess the intra, and interobserver reliability. Data were analyzed by ANOVA and Tukey’s test (alpha = 0.05).ResultsThe intra- and interobserver reliability were > 0.9 for all parameters. The largest inter-radicular distance in the maxilla was between the central incisors (1–1) in classes I and III, and between premolars (4–5) in class II patients. The largest inter-radicular distance in the mandible was between molar teeth (6–7) in all three classes. The buccal cortical plate thickness was maximum at the site of mandibular first and second molars (6–7). The posterior maxilla and mandible showed the maximum thickness of cancellous bone and alveolar process. Wide variations were noted in this respect between class I, II and III patients.ConclusionsThe area with maximum inter-radicular distance and optimal alveolar bone thickness for miniscrew insertion varies in different individuals, depending on their sagittal skeletal pattern.

Management of Compromised First Permanent Molar with Triple Antibiotic Paste in a 12-year-old Child: A Case Report

In teeth with pulpal and periapical infection, various group of microorganisms are present. Inhibition of the growth of these microorganisms and suppression of their antimicrobial activity play a crucial role in the success of the endodontic management. Triple antibiotic paste has been reported to have an excellent antimicrobial efficacy and it can be useful in management of teeth with severe infection. A 12-year-old female child reported with pain and swelling in relation with a lower left first permanent molar. Clinical examination of the tooth revealed deep occlusal caries and dentoalveolar abscess. Radiographically, the carious lesion was seen involving the pulp with periodontal ligament widening and inter-radicular bone loss was observed (endo-perio lesion). Considering the position of the tooth and its strategic importance, a conservative approach to salvage the tooth using Triple Antibiotic Paste (TAP) as a medicament was employed with complete radiographic healing by 12 weeks. Subsequent obturation using lateral condensation with gutta percha followed by composite restoration and preformed stainless steel crown was performed. This case report focuses on the endodontic management of perforated first permanent molar with compromised periodontal support and significant bone loss TAP as medicament and Mineral Trioxide Aggregate (MTA) as perforation repair material. Based on the results it can be concluded that Triple Anitibiotic Paste (TAP) can be effective in the disinfection and sterilization of the root canals and repair of complex lesions.

RADIOGRAPHIC FEATURES OF INTERCRESTAL AND CLASSIC OSTEOSARCOMA: A REPORT OF 3 CASES

<h3>BACKGROUND</h3> With this poster we add 2 new cases of intercrestal osteosarcoma to the 2 cases reported at the 2017 AAOMR annual meeting in the poster entitled, "Osteosarcoma: A Report of Two Cases With Similar Radiographic Features." One of the present intercrestal cases was clinically thought to be a "gingival epulis." These 2 additional cases serve to raise awareness of the importance of recognizing the radiographic features of osteosarcoma occurring in an intercrestal location. In addition, we present another case of osteosarcoma with the classical features of sunburst bone pattern, knife-edge root resorption, and periodontal ligament (PDL) widening. With these cases and the authors' own experience it is certainly true that osteosarcoma is the most common primary malignant bone tumor of the jaws.¹ <h3>CASE REPORT</h3> Intercrestal case 1: A young male patient presented with clinical swelling in the area of teeth #26 and #27. A panoramic radiograph revealed unilateral PDL widening on teeth #26 and #27 and displacement of these teeth. There was growth of the intercrestal bone and a patchy sclerotic nature to the interradicular bone pattern. Intercrestal case 2: A 63-year-old white female patient presented with a gingival nodule of 2 months' duration. Periapical and panoramic radiographs revealed PDL widening along tooth #21, displacement of teeth #20 and #21, growth of the intercrestal bone, and subtle radiolucent and radiopaque changes in the interradicular bone. Classical osteosarcoma case: A 53-year-old African American female patient presented with an expansile 2 × 2 cm firm, painful lesion associated with the mandibular left second molar. Panoramic and cone beam computed tomography images revealed a radiopaque bone pattern, PDL widening, tooth displacement, spiked root resorption, and sunburst bone pattern. <h3>DISCUSSION/CONCLUSIONS</h3> Intercrestal osteosarcoma may be a subtle relative of the expansion associated with the classic sunburst pattern. Meticulous attention to details is crucial during radiographic evaluation.

Influence of Inter-Radicular Septal Bone Quantity in Primary Stability of Immediate Molar Implants with Different Length and Diameter Placed in Mandibular Region. A Cone-Beam Computed Tomography-Based Simulated Implant Study.

Aim:The purpose of this in vitro study was to investigate the influence of length and width of implant on primary stability in immediate implants in mandibular first molar.Materials and Methods:The study was carried out on 40 cone-beam computed tomography scans selected with defined inclusion and exclusion criteria. According to the diameter and length of implants, they were divided into nine groups (G1 to G9). The virtual implants of different diameters and length were placed in mandibular first molar and measurements were done for peri-implant horizontal and vertical gap defect, peri-implant interradicular bone support and apical bone support for all the groups.Results:The study groups Diameter, (D-7 mm) showed least horizontal gap defect (Buccal-1.30 ± 0.56 mm, lingual-1.30 ± 0.56 mm, mesial-1.20 ± 0.51 mm, and distal-1.05 ± 0.59 mm) as compared to regular implant diameter (D-4.7) groups (Buccal-2.35 ± 0.483 mm, lingual-2.10 mm ± 0.44 mm, mesial-2.30 ± 0.64 mm, and distal-2.25 ± 0.43 mm). The unsupported Vertical implant gap defect at the coronal part of the socket was 2.80 mm ± 0.83 mm for all groups in both horizontal and vertical direction. The vertical peri-implant interradicular bone support showed increased bone support with increase in implant length (L). The buccal and lingual inter-radicular bone-support was least for Length (L-8.5 mm), moderate for L-11.5 mm, and highest for L-13.5 mm groups, respectively. The mesial inter-radicular bone support was least for G4G7, moderate for G1G2G5G8, and maximum for G3G6G9 groups. Similarly, the distal inter-radicular bone support was least for G4G7, moderate for G1G5G8, and maximum for G2G3G6G9 groups, respectively. There was no apical bone support in L-8.5 mm group as the tip of implant was 3.5–4 mm within the socket tip. Whereas, L-11.5 mm had decent (0.9–1 mm) and L-13.5 mm had Good (1.35–1.95 mm) apical bone support as the implant tip was beyond the socket tip.Conclusion:All the groups showed good interradicular bone support on buccal and lingual surfaces. Regular width implants with longer length showed satisfactory interradicular bone support on mesial and distal surfaces. Longer implants showed good apical bone support in all the four surfaces and hence good apical primary stability expected.

Inter radicular bone dimensions in primary stability of immediate molar implants – A cone beam computed tomography retrospective analysis

PurposeThe purpose of the study was to analyze the dimensions of socket morphology, interradicular bone dimensions, root length and morphology, buccal cortical bone thickness and gap defect between the implant bone in mandibular molars with cone beam computed tomography (CBCT) for immediate molar implant (IMI) placement. Materials and methodsSample sizes of 300 mandibular 1st and 2nd molars were each selected from the CBCT scans by inclusion and exclusion criteria. CBCT measurements were performed for socket size morphology, mesiodistal width, and buccolingual cancellous bone width at the crest at the apex. Width of the buccal cortical plate at the crest and interradicular bone (IRB) at the apex, 3 mm cervical to the apex and 6 mm cervical to the apex. Vertical parameters from the crest to furcation (L1), length from furcation to the apex (L2) and mesiodistal root morphology were measured to analyze the root configuration. ResultsAll the parameters were analyzed for descriptive statistics for the mean and standard deviation. The majority were of Type B and C socket morphology with peri-implant bone defects of 2–2.5 mm, and the interradicular bone septum (IRB) was moderate for both first molar (1 M) and second molar (2 M) sites, but 2 M was shown to have less IRB than 1 M. Adequate buccal cortical bone thickness of 1.1 mm to 1.4 mm and buccolingual cancellous bone width were measured for both the 1 M and 2 M sites. ConclusionThe morphology of the molar extraction socket determines the adequate stability for IMI. In mandibular molar teeth, where interradicular bone is incompetent in providing good primary stability, in addition to interradicular bone, clinicians should look for support from the apical bone and interdental septal bone for attaining primary stability of IMI.

Functional adaptation of interradicular alveolar bone to reduced chewing loads on dentoalveolar joints in rats

ObjectivesThe effects of reduced chewing loads on load bearing integrity of interradicular bone (IB) within dentoalveolar joints (DAJ) in rats were investigated. MethodsFour-week-old Sprague Dawley rats (N = 60) were divided into two groups; rats were either fed normal food, which is hard-pellet food (HF) (N = 30), or soft-powdered chow (SF) (N = 30). Biomechanical testing of intact DAJs and mapping of the resulting mechanical strains within IBs from 8- through 24-week-old rats fed HF or SF were performed. Tension- and compression-based mechanical strain profiles were mapped by correlating digital volumes of IBs at no load with the same IBs under load. Heterogeneity within IB was identified by mapping cement lines and TRAP-positive multinucleated cells using histology, and mechanical properties using nanoindentation technique. ResultsSignificantly decreased interradicular functional space, IB volume fraction, and elastic modulus of IB in the SF group compared with the HF group were observed, and these trends varied with an increase in age. The elastic modulus values illustrated significant heterogeneity within IB from HF or SF groups. Both compression- and tension-based strains were localized at the coronal portion of the IB and the variation in strain profiles complemented the observed material heterogeneity using histology and nanoindentation. SignificanceInterradicular space and IB material-related mechanoadaptations in a DAJ are optimized to meet soft food related chewing demands. Results provided insights into age-specific regulation of chewing loads as a plausible “therapeutic dose” to reverse adaptations within the periodontal complex as an attempt to regain functional competence of a dynamic DAJ.

The Influence of Ficus deltoidea in Preserving Alveolar Bone in Ovariectomized Rats.

Ficus deltoidea has been shown to possess antioxidant properties that could prevent the development of chronic inflammatory bone diseases. In this study, the efficacy of F. deltoidea in preventing alveolar bone resorption in osteoporotic rats induced by ovariectomy (OVX) was investigated. Twenty-four female Wistar rats were divided into four groups (n = 6) consisting of sham-operated (SO), ovariectomized control (OVXN), ovariectomized treated with estrogen (OVXP), and ovariectomized treated with F. deltoidea extract (OVXF). At the beginning of the study, two nonovariectomized, healthy rats were sacrificed to serve as baseline (BL). Treatment of the rats commenced two weeks after ovariectomy—the OVXP rats that served as positive control received Premarin® (64.5 μg/kg body weight), while OVXF rats were given F. deltoidea (800 mg/kg body weight); both agents were administered orally for two months. The negative control group of rats (OVXN) and the SO group received deionized water, also administered via oral gavage. At necropsy, morphometric assessment of the interradicular bone of the first molar was carried out using a micro-CT scanner, while quantification of osteoclasts and osteoblasts was performed histologically. The results showed that no statistically significant differences among the groups (p > 0.05) for bone morphometric assessment. However, trabecular thickness in the OVXF group was similar to BL, while trabecular separation and alveolar bone loss height were lower than those of the OVXN group. Histologically, the OVXF group demonstrated a significantly lower number of osteoclasts and a higher number of osteoblasts compared with OVXN (p=0.008 and p=0.019, respectively; p < 0.05). In conclusion, F. deltoidea has the capacity to prevent alveolar bone loss in ovariectomy-induced osteoporosis rats by potentially preserving trabecular bone microarchitecture and to decrease osteoclast and increase osteoblast cell count.

Comparison of non-contrast-enhanced dental magnetic resonance imaging and cone-beam computed tomography in assessing the horizontal and vertical components of furcation defects in maxillary molars: An in vivo feasibility study.

To compare non-contrast-enhanced dental magnetic resonance imaging (NCE-dMRI) and cone-beam computed tomography (CBCT) in assessing horizontal and vertical furcation defects in maxillary molars in vivo. (NCE-dMRI) and CBCT were performed in 23 patients with severe periodontitis. Sixty-five first/second maxillary molars (195 furcation entrances) were analysed by two independent observers on both modalities to assess the horizontal and vertical components of furcation defects. Reliability of defect classification was evaluated using weighted kappa (κ) statistics. Agreement between NCE-dMRI and CBCT was determined by the Bland-Altman analysis. Sensitivity and specificity of NCE-dMRI were calculated using CBCT as the reference. Inter-radicular bone loss was observed in 94 furcation entrances. Intra- and inter-rater κ-values were ≥0.9 for both NCE-dMRI and CBCT. The Bland-Altman analysis showed mean differences (95% limits of agreement) of 0.12mm (-0.67 to 0.90) for horizontal and 0.12mm (-1.27 to 1.50) for vertical measurements. For the detection of furcation defects, sensitivity/specificity of NCE-dMRI was 98%/100% for horizontal and 99%/99% for vertical components. For defect classification, sensitivity values of NCE-dMRI were 88%/89%/100% (horizontal degree I/II/III) and 95%/91%/80% (vertical subclass A/B/C), respectively. Non-contrast-enhanced dental magnetic resonance imaging demonstrated high reliability and high agreement with CBCT for the assessment of furcation defects in maxillary molars.

Signs of alveolar bone damage in early stages of periodontitis and its prevention by stimulation of cannabinoid receptor 2. Model in rats

The aims of the present study were, first, to identify signs of alveolar bone damage in early stages of experimental periodontitis (EP) and, second, to assess its possible prevention by treatment with cannabinoid receptor 2 agonist HU 308. Experimental periodontitis was induced by injections of lipopolysaccharide (LPS) (1mg/ml) in gums surrounding maxillary and mandibular first molar, 3 days per week, and untreated controls were kept for comparison. Then, a 3-week study was conducted including eighteen new rats (six rats per group): 1) controls; 2) experimental periodontitis rats; and 3) experimental periodontitis rats treated daily with HU 308 (500 ng/ml). After euthanasia, alveolar bone loss was assessed by morphometric and histomorphometric techniques, and the content of prostaglandin E2 (PGE2) in gingival tissue was evaluated by radioimmunoassay. The first signs of alveolar bone loss were apparent at 3 weeks of experimental periodontitis (ρ&lt;0.05) in the mandibular first molar, but there was no detectable change at 1 week, leading us to establish 3 weeks as an early stage of experimental periodontitis. Rats subjected to 3-week experimental periodontitis showed less interradicular bone volume, less whole bone perimeter and fewer bone formation areas, and higher periodontal space height, bone resorption areas, number of osteoclasts and gingival content of prostaglandin E2 than controls, while HU 308 prevented, at least partially, the deleterious effects (ρ&lt;0.001). We can conclude that a 3-week term of lipopolysaccharide-induced periodontitis in rats provides a valid model of the early stage of the disease, as emerging damage is observed in bone tissue. Furthermore, harmful effects at 3 weeks could be prevented by local stimulation of cannabinoid receptor 2, before greater damage is produced.

Mandibular biomechanical behavior of rats submitted to chronic intermittent or continuous hypoxia and periodontitis.

The aim of this study was to investigate the effects of exposure to continuous (CH) and intermittent (IH) hypoxia on biomechanical properties of the mandible and periodontal tissue of animals submitted to experimental periodontitis (EP) when applying loads in a hypoxic environment. Adult female Wistar rats were exposed during 90 days to IH or CH (simulated high altitude of 4200 m above sea level). Fourteen days prior to the euthanasia, EP was induced to half of the animals of each group. Only in the rats with EP, IH decreased the maximum capacity of the mandible to withstand load and the limit of elastic load. Indicators of intrinsic properties of the bone material were significantly reduced by both types of hypoxia in rats with EP. Hypoxia enhanced the alveolar bone loss induced by EP in the buccal side of the mandible, without showing additional effects in lingual or interradicular bone. Hypoxia increased prostaglandin E2 content in gingival tissue of healthy animals and further elevated the E2 levels increased by EP. When periodontitis is present, hypoxic stress induces a decrease in mineral properties that ultimately affects the ability of the mandible to resist load, mainly during intermittent exposure to hypoxia. These effects on bone may be related to the higher levels of prostaglandin E2 reached in the surrounding gingival tissue. The findings of this study may stimulate strategies to prevent unwanted effects of hypoxia on periodontal tissues.

Three-Dimensional Alveolar Bone Assessment of Mandibular First Molars with Implications for Immediate Implant Placement.

The aim of this retrospective study was to evaluate the alveolar dimensions of the mandibular molar using cone beam computed tomography (CBCT) for immediate implant placement. The width of buccal (WB) and lingual (WL) bone; width of interradicular bone 2 and 4 mm apical to the furcation and at the apex (IRB2, IRB4, and IRBA, respectively); and distance to the inferior alveolar nerve from the furcation (IAN-F) and mesial (IAN-M) and distal (IAN-D) roots were evaluated from CBCT records of 126 subjects (200 mandibular first molars). Mean WB (0.84 ± 0.39 mm) and WL (2.71 ± 1.17 mm) measurements showed significant differences (P = .003). Differences between IAN-F, IAN-M, and IAN-D measurements averaged at 14.14 ± 2.57 mm, 4.31 ± 1.06 mm, and 4.61 ± 1.02 mm, respectively. IRB2, IRB4, and IRBA dimensions were 1.93 ± 0.65 mm, 2.54 ± 0.9 mm, and 4.46 ± 1.91 mm, respectively. The findings of the study demonstrate the alveolar bone morphology of the mandibular first molar and the need for CBCT scans for proper treatment planning for immediate implant placement.

Treatment of class II malocclusion with bimaxillary dentoalveolar protrusion and compromised mandibular first molars through anchorage miniscrews (TADS)

Patients with dental Class II bialveolar protrusion are generally treated by extracting all four first premolars or two first and two second premolars, and retracting the anterior teeth. This case report describes the treatment of an adult female patient aged 21-year-old with bialveolar protrusion, a Class II canine and class II molar relationship along with lip protrusion. In this patient, the lower right and left mandibular first molar i.e., (3-6) and (4-6) had to be extracted due to extensive caries, also extraction was performed for maxillary 1st right and left bicuspids i.e., (1-4) and (2-4).Mini-implant (1.4 mm in diameter, 8 mm long) were placed in interradicular bone between the maxillary second bicuspids and first molars and mesial to mandibular second molar to allow en-masse retraction of upper and lower anterior teeth. Overall, miniscrews (TADs) can provide anchorage to produce a good facial profile in cases of dental Class II bialveolar protrusion with hopeless mandibular first molars.

Root Guided Immediate Implant Placement at Mandibular Molar Site: A Case Report

With the advancement in science and technology, Immediate implant placement has become a widely used and well accepted alternative to traditional treatment protocols. Post extraction implant placement in multicoated molar area is challenging. The primary stability in molar areas is achieved by engaging the interradicular bone but slipping of osteotomy drill to mesial or distal root socket during implant bed preparation is the main problem in post extraction immediate implant placement. Use of surgical guide, pre- extractive interradicular implant bed preparation and the combination of both these techniques has been used to overcome the problem related to immediate implant placement at molar sites. This paper presents an alternative approach in immediate Implant placement in multi rooted molar area that uses the anatomy and morphology of roots in guiding the osteotomy to provide an ideal3-dimensional implant positioning.

A three-dimensional analysis of primary failure of eruption in humans and mice.

Primary failure of eruption (PFE) is a genetic disorder exhibiting the cessation of tooth eruption. Loss-of-function mutations in parathyroid hormone (PTH)/parathyroid hormone-related peptide (PTHrP) receptor (PTH/PTHrP receptor, PPR) were reported as the underlying cause of this disorder in humans. We showed in a PFE mouse model that PTHrP-PPR signaling is responsible for normal dental follicle cell differentiation and tooth eruption. However, the mechanism underlying the eruption defect in PFE remains undefined. In this descriptive study, we aim to chronologically observe tooth eruption and root formation of mouse PFE molars through 3D microCT analyses. Two individuals with PFE were recruited at Showa University. A mouse PFE model was generated by deleting PPR specifically in PTHrP-expressing dental follicle and divided into three groups, PPRfl/fl ;R26RtdTomato/+ (Control), PTHrP-creER;PPRfl/+ ;R26RtdTomato/+ (cHet), and PTHrP-creER;PRRfl/fl ;R26RtdTomato/+ (cKO). Images from human PFE subjects were acquired by CBCT. All groups of mouse samples were studied at postnatal days 14, 25, 91, and 182 after a tamoxifen pulse at P3, and superimposition of 3D microCT images among three groups was rendered. Mouse and human PFE molars exhibited a similar presentation in the 3D CT analyses. The quantitative analysis in mice demonstrated a statistically significant decrease in the eruption height of cKO first and second molars compared to other groups after postnatal day 25. Additionally, cKO molars demonstrated significantly shortened roots with dilacerations associated with the reduced interradicular bone height. Mouse PFE molars erupt at a much slower rate compared to normal molars, associated with shortened and dilacerated roots and defective interradicular bones.

Management of Class II furcation defects in dogs using combination of Propolis and Nanobone graft

Background: Periodontal regeneration using complementary and alternative medicine has gained considerable attention recently. Propolis is a resinous hive product collected by honey bees from exudates and buds of plants and mixed with wax and bee enzymes.Objective: The aim of this study was to evaluate the effect of propolis as bone graft substitute in the management of experimental grade II furcation defects, and to compare its effect to nanobone and to Propolis/nanobone mixture. Material and Methods: Sixteen critical-sized furcation defects on the buccal surface of mandibular third and fourth premolars were surgically created in twelve dogs and divided into three groups. Group I; defects were filled with Propolis, Group II; defects were filled with nanohydroxyapatite graft and Group III; defects were filled with a combination of Propolis/ nanohydroxyapatite graft. Histologically and histomorphometric analysis of newly formed interradicular bone height and percentage were performed after one and three months. Results: After one month; the three experimental groups revealed the features of early periodontal tissues regeneration including cementum, newly formed bone with inserted newly formed PDL fibers. The propolis group showed the highest bone height and bone surface area. After three months; denser bone occupying larger surface area of the furcation defect were noted especially in the propolis group. Conclusion: The addition of nanobone to propolis showed better results than nano bone alone especially at early healing stage. However, it didn’t show better results than the use of propolis alone.

Fish oil diet effects on alveolar bone loss, in hypercholesterolemic rats

This study evaluated the effects of replacing a saturated fat diet by n-3 polyunsaturated fatty acids (n-3PUFA), on alveolar bone loss in hypercholesterolemic rats with experimental periodontitis (PD). MethodsEight week old Wistar rats were assigned according to dietary intake. Control group (C, n = 15) fed a commercial diet throughout the experiment. Atherogenic group (AT, n = 30) fed AT diet for 3 weeks; thereafter, AT was randomized to receive either a n-3PUFA (n = 15) or to continue with AT (n = 15) diet. Subsequently, PD was induced in all groups by unilateral ligature (L) of the first molar (M1) of the left mandible, non-ligated contralateral molars served as controls. After every week of PD induction, 5 rats per group were euthanized. Serum was collected for lipids assays and hemi-mandibles were subjected to histomorphometric (% upper and lower interradicular bone volume and periodontal ligament height, hPDL) and radiographic analyses (periodontal bone support, PBS, in ligated teeth, between M1-M2). ResultsRats fed n-3PUFA diet rapidly induced a significant reduction in the serum lipids (p < 0.001).In all rats the ligated teeth showed a greater bone loss as compared with the unligated molars. At the end of the experiment the AT + L was the worst in % lower bone volume (p < 0.01), hPDL and PBS (p < 0.05). In contrast, rats fed n-3PUFA + L was similar to those rats fed C diet (p > 0.05). ConclusionAlveolar bone and dyslipidemia improved by substituting saturated fat intake for a n-3PUFA rich diet, in hypercholesterolemic rats with PD.