Clinical and radiographic assessment of cross-linked hyaluronic acid addition in demineralized bovine bone based alveolar ridge preservation: A human randomized split-mouth pilot study.

PURPOSE: To investigate clinically and radiographically at 4 months post-operatively the outcomes of mixing demineralized bovine bone material (DBBM) with cross-linked hyaluronic acid in alveolar ridge preservation. MATERIAL AND METHODS: Seven patients presenting bilateral hopeless teeth (14 teeth) were enrolled in the study, the test site contained demineralized bovine bone material (DBBM) mixed with cross-linked hyaluronic acid (xHyA) while the control site contained only DBBM. 4 months post-operatively prior to implant placement a Cone beam computed tomography (CBCT) scan was recorded and compared to the initial scan to assess the volumetric and linear bone resorption that occurred in both sites. Clinically, sites that needed further bone grafting at the implant placement stage were recorded. Differences in volumetric and linear bone resorption between both groups were assessed using Wilcoxon signed rank test. McNemar test was also used to evaluate difference in bone grafting need between both groups. RESULTS: All sites healed uneventfully, volumetric and linear resorption differences between the baseline and 4 months post-operatively were obtained for each site. The mean volumetric and linear bone resorption were respectively 36.56 ± 1.69%, 1.42 ± 0.16 mm in the controls sites and 26.96 ± 1.83%; 0.73 ± 0.052 mm in the tests sites. The values were significantly higher among controls sites (P=0.018). No significant differences were observed in the need for bone grafting between both groups. CONCLUSION: Cross-linked hyaluronic acid (xHyA) appears to limit the post-extractional alveolar bone resorption when mixed with DBBM.

Assessment of soft and hard tissue characteristics of ridge preservation at molar extraction sites with severe periodontitis: a randomized controlled trial.

BACKGROUND: Changes in alveolar bone dimension after tooth extraction may affect placement of the subsequent implant, resulting in ridge deficiency that can adversely impact long-term implant stability or aesthetics. Alveolar ridge preservation (ARP) was effective in reducing the amount of ridge resorption following tooth extraction. There is sparse evidence regarding the benefit of ARP at periodontally compromised molar extraction sockets. This study will be a randomized trial to assess the soft tissue contour, radiographical, and histological changes of ARP at molar extraction sites in order to compare severe periodontitis cases with natural healing results and determine the most beneficial and least traumatic clinical treatment for such patients. METHODS: This research is designed as a two-group parallel randomized controlled trial. The total number of tooth extraction sites will be 70 after calculation with power analysis. Teeth will be randomly assigned to two groups with the test group conducting ridge preservation and the control group healing naturally. Periodontal examination, cone beam-computed tomography (CBCT) data, and stereolithographic (STL) files obtained by intraoral scanning will be collected through the follow-up period, and bone biopsy samples would be obtained during implant surgery. The primary outcomes are the vertical and horizontal change of alveolar ridge measured on CBCT images, soft tissue contour changes evaluated by superimposing the digital impressions, alterations of mucosa thickness (as measured by superimposing the CBCT data and STL files), histological features of implant sites and periodontal parameter changes. The secondary outcomes are patient-reported post-operative reaction and conditions of simultaneous bone graft or sinus lifting procedures during implantation. DISCUSSION: This study will provide information about hard and soft tissue dimension changes and histomorphology evaluation following ARP and natural healing in periodontally compromised molar sites, which may contribute to complement the missing information of ARP at periodontally compromised molar extraction sockets. TRIAL REGISTRATION: Chinese Clinical Trial Register (ChiCTR) ChiCTR2200056335. Registered on February 4, 2022, Version 1.0.

Assessment of a Novel Alveolar Ridge Preservation Concept in Dehiscence Sockets: A Pilot Study.

In this prospective pilot study on ridge preservation (RP), a collagen sponge was placed to fill the bottom half of the socket, followed by a sequence of bone graft, collagen membrane, and a sponge placed on top. Twelve patients with 13 hopeless posterior teeth were included. Changes in bone dimension (including variations of horizontal ridge width [HRW] and bone height [BH]) between the time immediately postextraction (T0) and 6 months later (T6M) were evaluated through CBCT. The soft tissue was assessed using a wound healing index (WHI) at 2 weeks (T2W), 2 months (T2M), and 6 months (T6M) postsurgery. Measured at three parallel levels (1, 3, and 5 mm apical to the crest of the palatal plate), the mean HRW changes (T0 to T6M) ranged from 0.47 to 1.05 mm. Statistically significant negative correlations were observed between WHI (T6M) and midcrestal BH change. This proposed RP technique showed favorable outcomes regarding HRW and BH, even in periodontally compromised dehiscence sockets.

Simultaneous Assessment of Soft and Hard Tissue Behaviors After Alveolar Ridge Preservation Using Bone Substitutes.

This study aimed to simultaneously assess hard and soft tissues alterations and their proportions after alveolar ridge preservation (ARP). Participants (n = 65) who were previously enrolled in a clinical trial investigating ARP healing were selected. The CBCT DICOM (Digital Imaging and Communications in Medicine) and the cast STL (stereolithographic) files of each subject were imported, segmented, and superimposed. A cross-section view of the superimposed image presented the outlines from each DICOM and STL file. The center of preserved ridge was selected in the superimposed image and used to draw the reference lines to realize the measurements. Horizontal linear measurements determined ridge width (RW) and its respective hard/soft tissue proportion (H:S) at 1, 3, 5, and 7 mm below the buccal bone crest immediately after ARP and at the 4-month follow-up. At 1 mm, the baseline RW was 11.6 mm and reduced to 10 mm after 4 months. The baseline H:S was 65%:35% and was 43%:57% at the 4-month follow-up. Considering only the buccal half of the ridge, baseline H:S was 77%:23%, while after 4 months it shifted to 58%:42%. A similar pattern was observed at 3, 5, and 7 mm but with decreased resorption degree. The present study showed that hard tissue is mostly responsible for RW loss after healing, especially in the first 3 mm below the buccal bone crest. Soft tissue partially compensated for the hard tissue shrinkage, gaining thickness in the analyzed areas.

Three-dimensional assessment of the extraction sockets, augmented with platelet-rich fibrin and calcium sulfate: A clinical pilot study.

OBJECTIVES: This clinical study assessed and compared the linear and volumetric changes of extraction sockets grafted with a combination of Platelet-Rich Fibrin (PRF) and Calcium Sulfate (CS) (PRF-CS), and extraction sockets grafted with a combination of PRF and xenograft (X) (PRF-X). METHODS: Five single maxillary premolar extraction sockets received PRF-CS grafts and five single maxillary premolar sockets received PRF-X grafts. Linear (horizontal and vertical) measurements were accomplished using Cone Beam Computed Tomography (CBCT) images and volumetric changes were assessed using MIMICS software. Soft tissue level changes were measured using Stonecast models. All measurements were recorded at baseline (before extraction) and at 5-months post-extraction. RESULTS: Significant reduction in vertical and horizontal dimensions were observed in both groups except for distal bone height (DBH = 0.44 ±â€¯0.45 mm, p = 0.09) and palatal bone height (PBH = 0.39 ±â€¯0.34 mm, p = 0.06) in PRF-X group. PRF-CS group demonstrated mean horizontal shrinkage of 1.27 ±â€¯0.82 mm (p = 0.02), when compared with PRF-X group (1.40 ±â€¯0.85 mm, p = 0.02). Vertical resorption for mesial bone height (MBH = 0.56 ±â€¯0.25 mm, p = 0.008), buccal bone height (BBH = 1.62 ±â€¯0.91 mm, p = 0.01) and palatal bone height (PBH = 1.39 ±â€¯0.87 mm, p = 0.02) in PRF-CS group was more than resorption in PRF-X group (MBH = 0.28 ±â€¯0.14 mm, p = 0.01, BBH = 0.63 ±â€¯0.39 mm, p = 0.02 and PBH = 0.39 ±â€¯0.34 mm, p = 0.06). Volumetric bone resorption was significant within both groups (PRF-CS = 168.33 ±â€¯63.68 mm3, p = 0.004; PRF-X = 102.88 ±â€¯32.93 mm3, p = 0.002), though not significant (p = 0.08) when compared between groups. In PRF-X group, the distal soft tissue level (DSH = 1.00 ±â€¯0.50 mm, p = 0.03) demonstrated almost 2 times more reduction when compared with PRF-CS group (DSH = 1.00 ±â€¯1.00 mm, 0.08). The reduction of the buccal soft tissue level was pronounced in PRF-CS group (BSH = 2.00 ±â€¯2.00 mm, p = 0.06) when compared with PRF-X group (BSH = 1.00 ±â€¯1.50 mm, p = 0.05). CONCLUSIONS: PRF-CS grafted sites showed no significant difference with PRF-X grafted sites in linear and volumetric dimensional changes and might show clinical benefits for socket augmentation. The study is officially registered with ClinicalTrials.gov Registration (NCT03851289).

Post-extraction mesio-distal gap reduction assessment by confocal laser scanning microscopy - a clinical 3-month follow-up study.

AIM: The aim of this 3-month follow-up study is to quantify the reduction in the mesio-distal gap dimension (MDGD) that occurs after tooth extraction through image analysis of three-dimensional images obtained with the confocal laser scanning microscopy (CLSM) technique. MATERIALS AND METHODS: Following tooth extraction, impressions of 79 patients 1 month and 72 patients 3 months after tooth extraction were obtained. Cast models were processed by CLSM, and MDGD changes between time points were measured. RESULTS: The mean mesio-distal gap reduction 1 month after tooth extraction was 343.4 µm and 3 months after tooth extraction was 672.3 µm. The daily mean gap reduction rate during the first term (between baseline and 1 month post-extraction measurements) was 10.3 µm/day and during the second term (between 1 and 3 months) was 5.4 µm/day. CONCLUSIONS: The mesio-distal gap reduction is higher during the first month following the extraction and continues in time, but to a lesser extent. When the inter-dental contacts were absent, the mesio-distal gap reduction is lower. When a molar tooth is extracted or the distal tooth to the edentulous space does not occlude with an antagonist, the mesio-distal gap reduction is larger. The consideration of mesio-distal gap dimension changes can help improve dental treatment planning.

Socket Preservation using Enzyme-treated Equine Bone Granules and an Equine Collagen Matrix: A Case Report with Histological and Histomorphometrical Assessment.

AIM: To histologically assess the effectiveness of a socket-preservation technique using enzyme-treated equine bone granules as a bone-graft material in combination with an equine collagen matrix as a scaffold for soft-tissue regeneration. BACKGROUND: Enzyme-treated equine bone granules and equine collagen matrix recently have been developed to help overcome alveolar bone deficiencies that develop in the wake of edentulism. CASE REPORT: The patient had one mandibular molar extracted and the socket grafted with equine bone granules. The graft was covered with the equine collagen matrix, placed in a double layer. No flap was prepared, and the gingival margins were stabilized with a single stitch, leaving the matrix partially exposed and the site to heal by secondary intention. The adjacent molar was extracted 1 month later, and that socket was left to heal by secondary intention without any further treatment. Three months after each surgery, an implant was placed and a biopsy was collected. The two biopsies underwent histological processing and qualitative evaluation. Histomorphometric analysis was also performed to calculate the percentage of newly formed bone (NFB) in the two cores. Healing at both sites was uneventful, and no inflammation or other adverse reactions were observed in the samples. Soft-tissue healing by secondary intention appeared to occur faster at the grafted site. The corresponding core showed a marked separation between soft and hard tissue that was not observed in the core from the nongrafted site, where soft-tissue hypertrophy could be observed. Newly formed bone at the grafted and nongrafted sites was not significantly different (27.2 ± 7.1 and 29.4 ± 6.2% respectively, p = 0.45). CONCLUSION: The surgical technique employed in this case appeared to facilitate postextraction soft-tissue healing by second intention and simplify soft-tissue management. CLINICAL SIGNIFICANCE: Using a collagen-based matrix to cover a postextraction grafted site may facilitate second intention soft-tissue healing and proper soft-tissue growth.

Risk assessment of inferior alveolar nerve injury for immediate implant placement in the posterior mandible: a virtual implant placement study.

OBJECTIVES: To investigate the prevalence and morphological parameters of lingual concavity, and whether these factors are related to a higher risk of inferior alveolar nerve (IAN) injury when performing an immediate implant surgery in posterior mandible region. METHODS: The CBCT images from 237 subjects (1008 teeth) were analysed the shape of the mandibles (C, P, U type), dimensional parameters of lingual concavity (angle, height, depth), and its relation to inferior alveolar canal (IAC) (A, B, C zone), RAC (distance from root apex to IAC) and probability of IAN injury. Multiple logistic regression modelling to determine the odds ratio of variables that made an important contribution to the probability of IAN injury and to adjust for confounding variables. RESULTS: The U type ridge (46.7%) and the most concave point located at C zone (48.8%) are most prevalent in this region. The mandibular second molar presents highest risk for IAN injury than other tooth type (p<0.001), which were 3.82 times to occur IAN injury than the mandibular second premolar. The concave point located at A zone and B zone were 7.82 and 3.52 times than C zone to have IAN damage, respectively. The probability of IAN injury will reduce 26% for every 1mm increase in RAC (p<0.001). CONCLUSIONS: The tooth type, morphological features of lingual concavities, and RAC are associated with risks of IAN injury during immediate implant placement. CLINICAL SIGNIFICANCE: Pre-surgical mapping of the IAC and identification of its proximity relative to the lingual concavity in the posterior mandible regions may avoid unpleasant complications, specifically when performing immediate implant procedures.

A pilot case-control study on the alveolar bone density measurement in risk assessment for bisphosphonate-related osteonecrosis of the jaw.

UNLABELLED: Alveolar bone mineral density (BMD) measured by radiography standardized by aluminum step wedge pasted on the film and digitized by a computer system was significantly higher around osteonecrosis lesions than in control cases in a pilot case-control study. High alveolar bone density appears useful as a local risk factor for bisphosphonate-related osteonecrosis of the jaw (BRONJ). INTRODUCTION: In an attempt to find a reliable test method predicting the occurrence of BRONJ in addition to various risk factors suggested, an increase of alveolar bone density near the necrotic lesions was found by computerized radiogrammetry using dental films pasted with an aluminum step wedge (Bone Right, Dentalgraphic.Com Company, Himeji) in six cases of BRONJ. METHODS: The bone mineral density surrounding the osteonecrosis lesions showed distinctly higher density in BRONJ cases compared with age-matched controls. In one subject on bisphosphonate treatment in whom two extractions were simultaneously carried out, BRONJ occurred only at the location with extremely high alveolar bone density, but not at the other site with normal density. CONCLUSION: This method may be useful in detecting a rise of alveolar BMD frequently occurring near the necrotic lesion in subjects with impending risk for BRONJ.

Bone healing after dental extractions in irradiated patients: a pilot study on a novel technique for volume assessment of healing tooth sockets.

The aim of this study was to evaluate longitudinally the bone-healing process by measuring volumetric changes of the extraction sockets in head and neck cancer patients undergoing radiotherapy after tooth extraction. A total group of 15 patients (nine males, six females) undergoing tooth extraction at the Department of Periodontology (University Hospital KULeuven) were enrolled after giving informed consent. In seven patients, teeth presenting a risk for complications and eventual radionecrosis were extracted prior to the radiotherapeutical procedure. Monitoring of bone healing was performed by evaluating the volumetric changes of the alveoli by cone beam CT scanning (CBCT) at extraction and after 3 and 6 months. In parallel, a similar longitudinal evaluation of extraction sites was done in a control group of eight patients. Within this pilot-study, a total of 15 healing extraction sockets were evaluated and followed up. There was a significant difference in volumetric fill up of extraction sockets in test group vs. control group at three (37.1 +/- 7.9%) vs. (54.6 +/- 4.0%) and 6 months (47.2 +/- 8.8%) vs. (70.0 +/- 7.3%), respectively. The present pilot study demonstrated the clinical usefulness of CBCT for evaluation of extraction socket healing. The study objectively demonstrates the delayed bone healing after tooth extraction in irradiated head and neck cancer patients. Considering the limitations of this pilot study, a potential effect of radiotherapy on further jaw bone healing after pre-therapeutic tooth extractions should be further explored.

Using the support immersion endoscope for socket assessment.

BACKGROUND: The purpose of this study was to determine the indications, efficacy, and advantages of the support immersion endoscope (SIE) method for extraction socket assessment. METHODS: Twelve patients (four women and eight men; mean age: 28 years) in need of extraction with implant placement participated in the study. The teeth extracted included eight upper central incisors and six upper lateral incisors. Extraction sockets were evaluated with a conventional extraction site evaluation (CESE) method alone or with CESE + SIE. CESE includes: visual evaluation; periodontal probing; ridge mapping with calipers, dental mirror, and orthopantomogram; and diagnostic wax-up. RESULTS: CESE + SIE had significantly better accuracy in examining extraction socket labial plate vertical position, labial plate thickness, and bone quality compared to CESE alone. The results obtained from CESE assessment were inconsistent because of poor visualization. CONCLUSION: The SIE can be used as an adjunct tool in assessing extraction socket morphology and bone conditions without flap elevation.

Radiographic assessment of impacted mandibular third molar sockets filled with composite xenogenic bone graft.

OBJECTIVES: The main purpose of this study was to evaluate the radiographic aspect of the healing of extraction sockets filled with a xenogenic graft material (Gent-tech). METHODS: Thirty-nine patients ranging in age from 15 years to 25 years with bilateral impacted mandibular molars were chosen based on bilateral mandibular similarities. After tooth extraction, the socket was filled with the graft. The opposite site was left to heal naturally and served as a control. The experimental and control sites were chosen randomly. Bone density and crest healing were evaluated on digital radiographs taken immediately, 2 months and 6 months after surgery. The respective pixels values obtained with the Digora software were compared statistically. RESULTS: The results showed a significant decrease in the distance from the cemento-enamel junction to the alveolar bone crest, but no difference was found between the control and experimental groups. Bone density increased significantly, and there was difference between experimental and control groups. CONCLUSION: The analysed parameters observed by the authors were similar to those of the control group, suggesting xenogenic graft being an acceptable material and a graft option.

Two- and three-dimensional sonographic assessment of the fetal face. 2. Analysis of cleft lip, alveolus and palate.

OBJECTIVES: To describe the sonographic appearance of cleft lip with or without cleft palate (CL +/- P) using two-dimensional and three-dimensional (3D) ultrasound imaging. Also, to evaluate the accuracy of ultrasound to delineate with precision the bony extent of facial clefts, i.e. to differentiate clefts limited to the lips, or extending to the alveolus/premaxilla or the secondary palate. METHODS: This was a retrospective study based on the examination of fetuses diagnosed with an isolated CL +/- P. Cases included were either discovered at systematic screening or referred for further investigation. Clefts were characterized by their precise anatomical location and extent. The defect could include a cleft lip (CL), a cleft alveolus (CA), or a cleft of the secondary palate (CSP). RESULTS: We analyzed 96 cases of CL +/- P. The mean gestational age at examination was 28.2 +/- 4.1 weeks. The sonographic appearance of CL, CA, and CSP was depicted. Strict concordance of the sonographic report with the anatomical defect was present in 84 cases (87.5%). In eight cases, the severity of the cleft was underestimated: three cases of CA, four of CA + CSP and one of CSP were missed. In four cases, the cleft was overestimated as CA was incorrectly suspected. CONCLUSIONS: Systematic screening with sonography to detect prenatally CL +/- P requires the imaging of at least the mid-sagittal and the anterior coronal 'nose-mouth' views. Once the presence of a facial cleft is suspected, the three reference orthogonal planes are imaged in order to characterize the anatomical defect, and for each plane, the serial scans are thoroughly examined. This protocol allows precise delineation of the defect. Inclusion of 3D and 4D ultrasound imaging in the examination protocol allows easier and more rapid screening and more precise evaluation of the different cleft constituents.