Alveolar ridge preservation in rat tooth extraction model by chitosan-derived epigenetic modulation scaffold

PURPOSE

Alveolar ridge preservation is a surgical technique used to prevent dimensional changes in the alveolar bone by dressing biomaterials in the extraction socket. Recently, a chitosan biphasic calcium phosphate loaded with trichostatin A (CS/BCP/TSA) scaffold was introduced as an excellent bone-regeneration material. This study aimed to explore the biological properties of released trichostatin A (TSA) and evaluate the potential of the CS/BCP/TSA scaffold in preserving the alveolar ridge in a rat tooth extraction model.

METHODS

In vitro biocompatibility, histone deacetylase (HDAC) activity, and osteogenic differentiation of MC3T3-E1 cells were tested. For in vivo studies, the maxillary first molars (M1) of Wistar rats were extracted, and alveolar ridge preservation was performed using a CS/BCP/TSA scaffold or commercial bone graft. Micro-Computed Tomography (micro-CT), polyfluorochrome labeling, and histological analysis were used to evaluate the ridge-preservation ability.

RESULTS

The released TSA was cytocompatible. Inhibition of histone deacetylase (HDAC) activity and induction of osteogenic differentiation in MC3T3-E1 cells were confirmed. The socket dressing with the CS/BCP/TSA scaffold showed increased socket bone fill and preserved the buccal and middle aspects of the alveolar ridge compared with the conventional graft. Further analysis of the bone regeneration ability by histomorphometric and histological analyses demonstrated that CS/BCP/TSA showed a significantly higher potential to induce bone formation and complete healing in the extraction socket than the other groups.

CONCLUSIONS

The CS/BCP/TSA scaffold is a novel candidate for alveolar ridge preservation.

Comparison of crestal bone loss and papilla fill after conventional and immediate implant placement: A 12 month clinical and radiographic prospective study

Background

The problem of missing teeth persists in all age groups. The main objective of implants in dentistry is to provide a restoration that reconstructs the shape and restores esthetics and functions of edentulous areas. The objectives of this study are to compare the crestal bone level changes and papillary fill after placement of implants in fresh extraction socket, i.e. immediate implant placement, and healed extraction socket, i.e. delayed or conventional implant placement, and to assess other clinical parameters such as modified plaque index (mPI), modified gingival index (mGI) and gingival biotype in between the groups and within the groups.

Methods

18 patients were recruited in the study out of which 9 patients received implants as per immediate implant placement protocol (group 1) and 9 patients received implants as per conventional implant placement protocol (group 2). All patients were evaluated for gingival biotype, mPI and mGI and papillary fill was assessed as per Jemt's papilla score as clinical parameters. Implant site was assessed for radiographic bone loss using Image J software. Statistical analysis was performed using independent t test, paired t test and chi square test.

Results

At the end of 1 year, results showed that crestal bone loss was seen more in the immediate group than the conventional group. Conventional implants showed better papillary fill than implants placed in fresh extraction sockets. Plaque scores were assessed as per modified plaque index, which showed better results in the conventional group. Modified gingival index was used to assess gingival status which showed better results in the immediate group one year later.

Conclusions

Findings from the study suggest that crestal bone loss was found to be increased in the immediate group than the conventional group and papillary fill was better in the conventional group than the immediate group.Registration: CTRI ( CTRI/2019/09/021340).

Zoledronate treatment exerts sex-independent effects on bone and dental physicochemical properties in mice jaw necrosis

INTRODUCTION

Bisphosphonate (BF) therapy is strongly related to the occurrence of medication-related osteonecrosis of the jaw (ONJ). However, no previous study has evaluated if there are sex-related differences on the ONJ establishment together with bone biomechanical alterations, and if they could have a synergy with the ZA treatment.

MATERIALS AND METHODS

This study aimed to analyze the physicochemical properties of mineralized tissues in a zoledronate (ZA)-related osteonecrosis mouse model, by a 2 × 2-factorial design, considering sex (female/male) and treatment (ZA/Saline) factors (n = 8/group). After three ZA (1.0 mg/kg) or saline administrations (days 0, 7, 14), the lower left second molar was extracted (day 42). Further ZA administration (day 49) and euthanasia (day 70) were conducted. After confirmation of ZA-induced jaw necrosis (histologic and microtomographic analysis), spectroscopic and mechanical parameters were assessed.

RESULTS

ZA-treated groups presented lower bone density due to impaired healing of tooth extraction socket. Sex-related alterations were also observed, with lower bone density in females. Regarding biomechanical parameters, sex and treatment exerted independent influences. ZA, although decreasing flexural modulus and yield stress, increases stiffness mainly due to a higher bone volume. Females show less resistance to higher loads compared to males (considering dimension-independent parameters). Additionally, ZA increases crystallinity in bone and dental structure (p < 0.05). In summary, although strongly related to osteonecrosis occurrence, ZA modifies bone and dental mineral matrix, improving bone mechanical properties.

CONCLUSION

Despite sex-dependent differences in bone biomechanics and density, osteonecrosis was established with no sex influence. No synergistic association between sex and treatment factors was observed in this study.

Effects of Photobiomodulation Therapy on Hard Tissue Healing in Rat Tooth Extraction Sockets

Objective: To investigate the effects of photobiomodulation therapy (PBMT) on hard tissue healing in rat maxillary first molar extraction sockets. Methods: A total of 20 male Wistar rats were used in the study. The right extraction sockets were irradiated with a Ga-Al-As laser (500 mW, 980 nm) for 51.7 J/cm2 every 24 h for 7 days, while the left sockets served as controls. Rats were sacrificed on days 3, 7, 14, and 28 after tooth extraction, and microcomputed tomography (CT) analysis, histopathological evaluation, and enzyme-linked immunosorbent assay (ELISA) were conducted at different time points. Results: Micro-CT analysis showed that the percentage of bone volume/tissue volume (TV) and bone mineral density were significantly higher in the experimental group compared to the control group on day 28 (p < 0.05). Histopathological evaluation revealed that PBMT promoted new bone formation and accelerated bone remodeling. ELISA demonstrated a significant increase in alkaline phosphatase expression in the laser sides on days 7 and 14 (p < 0.05). Conclusions: One application postextraction followed by seven consecutive daily applications of PBMT can effectively promote hard tissue healing in rat maxillary first molar extraction sockets.

Patterns of recurrence in patients undergoing curative treatment for maxillary alveolus squamous cell carcinoma

The aim of this paper was to examine patterns of recurrence in patients undergoing curative treatment for maxillary alveolus squamous cell carcinoma (MASCC). Clinicopathological data on 41 patients undergoing curative resection for MASCC between February 2006 and May 2020 were retrospectively gathered. Outcomes included local, regional, or distant failure as first site of treatment recurrence. Univariate analysis identified significant clinicopathological variables for type of recurrence. Multivariate regression analysis generated predictive models. Ten of 41 patients developed regional recurrence, and nine manifested contralateral recurrence following ipsilateral neck dissection. In three patients the ipsilateral neck was pN0. Nodal metastasis was predictive of regional recurrence, particularly with extranodal tumour extension (ENE). Multivariate analysis with regional recurrence confirmed that ENE was independently predictive. Nodal disease and ENE in patients with MASCC was found to be predictive of contralateral regional recurrence. Management of the neck in MASCC that extends to the palatal aspect should therefore be considered as midline disease.

A new gnathosaurine (Pterosauria, Archaeopterodactyloidea) from the Late Jurassic of Portugal

An incomplete, yet remarkably-sized dentated rostrum and associated partial cervical vertebrae of a pterosaur (ML 2554) were recently discovered from the Late Jurassic (Late Kimmeridgian-Early Tithonian) Lourinhã Formation of Praia do Caniçal, of central west Portugal. This specimen exhibits features such as a spatulated anterior expansion of the rostrum, robust comb-like dentition, and pronounced rims of the tooth alveoli, indicating gnathosaurine affinities. Based on its further unique tooth and dentary morphology, a new genus and species, Lusognathus almadrava gen. et spec. nov., is proposed, making this the first named pterosaur species found within Portugal. The presence of this taxon adds yet another element to the fluvio-deltaic lagoonal environment that has been suggested as representative of the Lourinhã Formation in the Late Jurassic, further contributing to the diversity and distribution of gnathosaurines worldwide.

Regeneration processes of alveolar bone and microvascular changes after the application of platelet-rich fibrin

OBJECTIVES

Platelet-rich fibrin (PRF) is a promising agent for bone regeneration (BR). Platelets contain several growth factors that promote angiogenesis and BR. In this study, we observed the morphology of alveolar BR.

METHODS

PRF (Advanced PRF: A-PRF) was prepared by extracting 10 mL of blood from each dog in a collection tube before tooth extraction. The samples were centrifuged at 200 × g for 8 min and incubated for 10 min to allow clotting. The alveolar socket on the dentition's right side was densely filled with PRF. The opposite side, which did not receive PRF, served as the control group. Different methods were used for specimen preparation and observation. Sections stained with hematoxylin and eosin were observed under a light microscope. Bone specimens were observed using stereoscopic microscopy. The resin cast models were examined using a scanning electron microscope. Moreover, bone formation ratio and height were measured.

RESULTS

Fourteen days postoperatively, angiogenesis and bone deposition were more advanced in the PRF group than in the control group. Thirty days postoperatively, both groups developed porous bone. In the PRF group, new bone trabeculae (BT) and a network of blood vessels were formed in the bone marrow. Ninety days postoperatively, the resin cast showed a normal bone structure with BT and bone marrow. Thick BT were observed in the PRF group.

CONCLUSIONS

Growth factors in PRF stimulate microcirculation and promote angiogenesis and bone deposition. The benefits of PRF include safety and increased bone formation.

Inhibition of Mertk Signaling Enhances Bone Healing after Tooth Extraction

Regeneration of alveolar bone is an essential step in restoring healthy function following tooth extraction. Growth of new bone in the healing extraction socket can be variable and often unpredictable when systemic comorbidities are present, leading to the need for additional therapeutic targets to accelerate the regenerative process. One such target is the TAM family (Tyro3, Axl, Mertk) of receptor tyrosine kinases. These proteins have been shown to help resolve inflammation and maintain bone homeostasis and thus may have therapeutic benefits in bone regeneration following extraction. Treatment of mice with a pan-TAM inhibitor (RXDX-106) led to accelerated alveolar bone fill following first molar extraction in a mouse model without changing immune infiltrate. Treatment of human alveolar bone mesenchymal stem cells with RXDX-106 upregulated Wnt signaling and primed the cells for osteogenic differentiation. Differentiation of human alveolar bone mesenchymal stem cells with osteogenic media and TAM-targeted inhibitor RXDX-106 (pan-TAM), ASP-2215 (Axl specific), or MRX-2843 (Mertk specific) showed enhanced mineralization with pan-TAM or Mertk-specific inhibitors and no change with Axl-specific inhibitor. First molar extractions in Mertk-/- mice had increased alveolar bone regeneration in the extraction socket relative to wild type controls 7 d postextraction. Flow cytometry of 7-d extraction sockets showed no difference in immune cell numbers between Mertk-/- and wild type mice. RNAseq of day 7 extraction sockets showed increased innate immune-related pathways and genes associated with bone differentiation in Mertk-/- mice. Together, these results indicate that TAM receptor signaling, specifically through Mertk, can be targeted to enhance bone regeneration after injury.

The root submergence technique at single tooth sites to short-span edentulous sites: A step-by-step partial extraction therapy protocol

Submerging roots for ridge preservation was the earliest partial extraction therapy and has been described since the 1970s. Despite the approximately 47 animal and human studies published since, an updated and contemporary step-by-step protocol has not yet been provided. This technique report describes in detail how to manage submerged roots at single tooth sites and at short-span edentulous areas.

Effect of the use of platelet concentrates on new bone formation in alveolar ridge preservation: a systematic review, meta-analysis, and trial sequential analysis

OBJECTIVES

To investigate the histomorphometric changes occurring in alveolar ridge preservation (ARP) based on the use of different plasma concentrates (PCs) in randomized clinical trials (RCT). There is controversy whether the placement of PCs in ARP is effective in the formation of new bone.

MATERIALS AND METHODS

A systematic review search was conducted in PubMed, Scopus, Web of Science, and Cochrane Database to answer the PICO question: In patients undergoing tooth extraction followed by ARP, do PCs alone in the post-extraction socket in comparison with spontaneous healing improve new vital bone formation percentage in histomorphometric analysis after more than 10 weeks? The risk of bias was assessed and a meta-analysis was conducted.

RESULTS

Of 3809 results, 8 studies were considered suitable for inclusion. A total of 255 teeth were extracted in 250 patients. Regarding the PCs used, ARP was performed with platelet- and leukocyte-rich fibrin (L-PRF) in 120 sockets, and with pure platelet-rich plasma (P-PRP) in 31 sockets and 104 sockets were controlled. PCs improved new bone formation in ARP with respect to the spontaneous healing group (SMD = 1.77, 95%C.I. = 1.47-2.06, p-value < 000.1). There were no differences between the different PCs (L-PRF and P-PRP).

CONCLUSION

The results of this meta-analysis support the efficacy of the use of PCs in new bone formation in ARP. With respect to the different types of PCs studied, no differences were observed.

CLINICAL RELEVANCE

When planning implant surgery after tooth extraction, treatment with PCs should be considered for ARP. Any PC increases new bone formation compared to spontaneous healing.

Sleeveless guided implant placement compared to conventional approaches: An in vitro study at healed sites and fresh extraction sockets

PURPOSE

To investigate the accuracy of a novel sleeveless implant surgical guide by comparing it with a conventional closed-sleeve guide and a freehand approach.

MATERIALS AND METHODS

Custom resin maxillary casts with corticocancellous compartments were used (n = 30). Seven implant sites were present per maxillary cast, corresponding to healed (right and left first premolars, left second premolar and first molar) and extraction sites (right canine and central incisors). The casts were assigned into three groups: freehand (FH), conventional closed-sleeve guide (CG) and surgical guide (SG) groups. Each group comprised 10 casts and 70 implant sites (30 extraction sites and 40 healed sites). Digital planning was used to design 3D printed conventional and surgical guide templates. The primary study outcome was implant deviation.

RESULTS

At extraction sites, the largest difference between groups occurred in angular deviation, where the SG group (3.80 ± 1.67 degrees) exhibited ~1.6 times smaller deviation relative to the FH group (6.02 ± 3.44 degrees; P = 0.004). The CG group (0.69 ± 0.40 mm) exhibited smaller coronal horizontal deviation compared to the SG group (1.08 ± 0.54 mm; P = 0.005). For healed sites, the largest difference occurred for angular deviation, where the SG group (2.31 ± 1.30 degrees) exhibited 1.9 times smaller deviation relative to the CG group (4.42 ± 1.51 degrees; P < 0.001), and 1.7 times smaller deviation relative to the FH group (3.84 ± 2.14 degrees). Significant differences were found for all parameters except depth and coronal horizontal deviation. For the guided groups, there were fewer significant differences between healed and immediate sites compared to the FH group.

CONCLUSION

The novel sleeveless surgical guide showed similar accuracy to the conventional closed-sleeve guide.

Flap Extension Technique Using Intrasocket Granulation Tissue in Peri-Implant Osseous Defect: Case Series

A compromised extraction socket is characterized by severe bone resorption around neighboring teeth and is often occupied with thick intrasocket granulation tissue (IGT). Guided bone regeneration (GBR) is a procedure that can preserve the bone volume around extraction sockets, and it can also be combined with immediate implant placement. However, an early exposure of GBR sites is a possible complication because it increases the risk of infection and can inhibit successful bone regeneration. The purpose of these case series is to introduce a novel, surgical procedure that can prevent the exposure of GBR sites by using IGT for flap extension during immediate implant placement in compromised extraction sockets. The technique was successfully performed in six patients. For successful flap closure, the inner portion of the IGT was dissected so that the flap was properly extended with the base of IGT attached to the flap for blood supply. Periosteal releasing incisions were not performed. The IGT was first sutured to the palatal flap with resorbable sutures, and then the overlying flap was closed with additional sutures. There was no post-operative exposure of the surgical GBR site in any of the patients, and the location of the mucogingival junction remained unchanged. All grafted sites also achieved sufficient bone regeneration. Within the limitations, this case series demonstrates the potential use of IGT, a concept which was previously obsolete.

Autotransplantation: a lost art worthy of revival in the era of implants

While synthetic implants represent a significant contribution to the advancement of dental medicine, they are associated with high costs, potential complications, and time delays. With autotransplantation, the patient is both donor and recipient of a living tooth; in the ideal case, this procedure transfers a healthy, nonfunctional tooth to a functional position. The aim of this article is to review the literature surrounding autotransplantation and present a successful case with the hope of increasing awareness of this approach to tooth replacement. A 20-year-old patient presented with a maxillary right second molar showing poor prognosis for restoration, and the patient's financial difficulties rendered extraction the only treatment option. The patient's fully soft tissue-impacted maxillary right third molar was atraumatically extracted and transplanted as a replacement for the second molar. The autotransplantation technique was enhanced via use of bone allograft to adapt the distal portion of the socket to the transplant, immediately reestablishing a healthy bony anatomy. In addition to reviewing the biologic basis, high success rate, and advantages of tooth autotransplantation, this article introduces a naming convention for transplanted teeth.

Clinical efficacy of the socket shield technique used in the aesthetic zone: A systematic review and meta-analysis

PURPOSE

To systematically review and analyse the efficacy of the socket shield technique in conjunction with immediate implant placement in the aesthetic zone in randomised controlled trials.

MATERIALS AND METHODS

The PubMed, Web of Science, Embase and Cochrane databases were searched from 1 January 2010 to 31 December 2020. All randomised controlled trials reporting on immediate implantation with the socket shield technique in the aesthetic zone, with at least 15 patients and a 6-month follow-up, were included and analysed. A meta-analysis was then performed using both fixed and random effects models to evaluate the differences in buccal plate height, buccal plate width and pink aesthetic score between immediate implant placement with the socket shield technique and the conventional immediate implant placement technique.

RESULTS

Four randomised controlled trials were included and underwent quantitative analysis in the present systematic review and meta-analysis. When compared with the conventional immediate implantation group, the buccal plate height and buccal plate width for the socket shield technique group were statistically significant, with an overall increase of 0.57 mm (95% confidence interval -0.73 to -0.40) and 0.21 mm (95% confidence interval -0.26 to -0.16), respectively, at 6 months. Moreover, the pink aesthetic score for the socket shield technique group improved significantly by 1.59 points (95% confidence interval 0.05 to 3.15) at 6 months, and also demonstrated a statistically significant increase of 1.39 points (95% confidence interval 0.32 to 2.46) compared to the control group at the medium-term follow-up (12 to 36 months).

CONCLUSIONS

The present findings suggest that the socket shield technique has the potential to maintain buccal tissue contours and peri-implant tissue stability, improving functional and aesthetic outcomes in the aesthetic zone compared with the conventional immediate implant placement technique.

[Effect of rat allogeneic BMSCs-Bio-Oss-bFGF compound on tooth extraction healing: a micro-CT study]

PRUPOSE

To investigate the effect of a compound of BMSCs-Bio-Oss-bFGF on microstructure of extraction sockets in rats.

METHODS

Bone mesenchymal stem cells (BMSCs) were isolated from bone marrow of 3-week SD rats by adherent method. Maxillary posterior teeth of 36 6-week SD rats were extracted and materials were implanted into sockets according to grouping. The rats were divided into 4 groups: compound group with implanting BMSCs-Bio-Oss-bFGF compound, powder group with implanting Bio-Oss, BMSCs group with implanting BMSCs, and control group without implanting any materials. The sockets were scanned by micro-CT 4 weeks, 12 weeks and 24 weeks after implantation. Two-way ANOVA was used to assess whether there was significant difference between groups with GraphPad Prism 6.0 software package.

RESULTS

There was no significant difference among groups in bone mineral density (BMD), trabecular separation(Tb.Sp), trabecular thickness(Tb.Th), degree of anisotropy(DA), and trabecular number(Tb.N) 4 weeks after implantation. By 12 weeks, BMD of compound group was significantly greater than those of BMSCs group, powder group and control group (P＜0.05), and significantly greater than those of powder group and control group at 24 weeks (P＜0.05). Tb.Th of compound group was significantly greater than that of BMSCs group at 12 and 24 weeks(P＜0.05). DA had no significant difference among groups at 4, 12, and 24 weeks (P＞0.05). Tb.Sp of compound group was significantly smaller than those of powder group, BMSCs group and control group at 24 weeks(P＜0.05). Tb.N of compound group was significantly greater than those of BMSCs group and control group(P＜0.05).

CONCLUSIONS

The compound of rat allogeneic BMSCs-Bio-Oss-bFGF improves socket healing.

Root Membrane Concept: Shield the Socket-A Case Report

Edentulousness affects the mental health of most patients. Missing teeth in the anterior esthetic zones is a matter of concern, especially for young adults. Various replacement options such as fixed partial dentures, removable partial dentures, and dental implants are available to treat edentulousness. Dental implants have been a booming treatment option in modern-day dentistry as they more closely mimic the natural tooth. The most important criterion for placement of the implant in the esthetic zone is the conservation of alveolar bone, especially in the anterior region which is usually compromised due to tooth extraction or resorption of the ridge. The root membrane concept or the socket shield technique is a recently introduced concept in implant dentistry where a portion of the root acts as a shield to protect against alveolar bone resorption and maintain bone integrity, especially in the esthetic area. This case report describes the clinical management of fractured upper anterior teeth using a dental implant and the root membrane technique. Keywords: Anterior zone, Esthetics, Immediate implants, Implant, Missing teeth, Root membrane technique, Socket shield.

Zoledronic Acid Deteriorates Soft and Hard Tissue Healing of Murine Tooth Extraction Sockets in a Dose-Dependent Manner

The pathophysiology, histopathology, and immunopathology of bisphosphonate-related osteonecrosis of the jaw (BRONJ) Stage 0 remain unclear. The aim of this study was to investigate the effects of high-dose bisphosphonates on tooth extraction socket healing by creating a murine model of BRONJ Stage 0-like lesions using 8-week-old female C57BL/6J mice. Zoledronic acid (Zol) was administered subcutaneously twice a week for 7 weeks at doses of 0.1 mg/kg/week (moderate dose; Zol-M), 0.5 mg/kg/week (high dose; Zol-H1), and 1.0 mg/kg/week (higher dose; Zol-H2). Saline was used as a control (VC). Both maxillary first molars were extracted 3 weeks after drug treatment. Maxillae, long bones, and sera were collected 4 weeks post-extraction (n = 7 mice/group). Microcomputed tomography, histological, immunohistochemical, and ELISA analyses were performed. A ceiling effect for Zol was noted at the Zol-H1 dose. Osseous healing of extraction sites was significantly impaired with increased necrotic bone and the number of empty lacunae in a Zol dose-dependent manner. Zol significantly decreased epithelial thickness, due to a decrease in thickness of the stratum spinosum, in both Zol-H1 and Zol-H2. Both Zol-H1 and Zol-H2 significantly suppressed the distribution of F4/80⁺ macrophages in the connective tissue of tooth extraction sockets, although gross healing appeared to be normal. Intriguingly, both Zol-H1 and Zol-H2 significantly increased the numbers of TRAP⁺ mononuclear cells and detached osteoclasts in the connective tissue and bone marrow of extraction sites compared to VC and Zol-M, correlated with serum TRAcP5b levels. The created murine model of BRONJ Stage 0-like lesions becoming more severe in a dose-dependent manner may help to understand the pathophysiology and histopathology of BRONJ Stage 0 in humans.

Evaluation of osteogenic potential of Cissus quadrangularis on mandibular alveolar ridge distraction

BACKGROUND

This randomized clinical trial was designed to evaluate osteogenic potential of Cissus quadrangularis in alveolar distraction to facilitate implant installation.

MATERIAL AND METHODS

Twenty patients with atrophic ridge were treated by alveolar distraction. After completing distractor activation, patients were randomly divided into two equal groups according to administered drug (placebo and Cissus quadrangularis group). After a consolidation period, distractors were removed and implants were inserted. Clinical evaluation was done to assess wound healing, and distractor and implant stability. Histological evaluation was performed at time of implant insertion. Radiographic evaluation was performed to assess bone volume and density after distraction, as well as, density and bone loss around implant.

RESULTS

Radiographic and histological results showed that bone formation and maturation of study group were faster than that of control group. There was a significant increased bone density in distracted area and around implant in study group than control group. A significant bone loss at end of consolidation period, and around implant at end of the study was reported in control group than study group.

CONCLUSION

Cissus quadrangularis administration during the consolidation period is associated with increased osteogenic potential of distracted bone. The histological and radiographic findings of current study proved that Cissus quadrangularis not only enhances rate of new bone formation, but also bone density to withstand the biomechanical requirements of implant placement in a shorter time. Trial registration This study was retrospectively registered on www.ClinicalTrial.gov : NCT04669795-17\12\2020.

Effects of 3% binahong ( Anredera cordifolia) leaf extract gel on alveolar bone healing in post-extraction tooth socket wound in Wistar rats ( Rattus norvegicus)

Background: Binahong ( Anredera cordifolia (Ten.) STEENIS) is a widely available herbal plant in Indonesia and has been intensely researched for its healing abilities due to its biological activities, but few have studied its capability in accelerating hard tissue healing in post-extraction tooth sockets. The purpose of this study was to analyse the effects of 3% binahong leaf extract gel on alveolar bone healing in post-extraction sockets in Wistar rats. Methods: In this study, 48 male Wistar rats were randomly allocated to twelve groups. After the extraction of the left mandibular incisor, sockets in Group I to IV were given 3% binahong leaf extract gel, group V to VIII were given a control gel, and group IX to XII were given Gengigel ® for 14 days. The residual socket volume (RSV) and fibroblast proliferation were observed on the 3 rd, 7 th, and 14 th day post-extraction, while the osteoblast and osteocyte proliferation were observed on the 7 th, 14 th, and 28 th day post-extraction. The RSV data were analysed using repeated measure ANOVA and one-way ANOVA, while the histopathological data were analysed using one-way ANOVA. Results: The results showed that the binahong group had the lowest RSV and the highest fibroblast proliferation compared to the other groups on the 7th day (p<0.05) and the highest osteoblast and osteocyte proliferation compared to the other groups on the 14 th day (p<0.05). Conclusion: The experiment showed that 3% binahong leaf extract gel could accelerate wound closure, which was characterized by a greater decrease in the RSV value in comparison to the other treatment groups and could enhance alveolar bone healing by increasing the proliferation of fibroblasts, osteoblasts, and osteocytes.

Local RANKL delivery improves socket healing in bisphosphonate treated rats

Medication related osteonecrosis of the Jaws (MRONJ) is a severe complication of antiresorptive and anti-angiogenic medications. Osteoclast inhibition is central in MRONJ pathogenesis. Here, we investigated if local application of RANKL (a key molecule in osteoclast activation) could enhance osteoclast generation and improve extraction socket healing in the presence of bisphosphonates. Thirty Wistar-Han rats received one saline or 66 μg/kg zoledronate (ZA) i.p. dose before surgery. A week later, mandibular molars were extracted bilaterally. Collagen tapes infused with water or RANKL were placed in the extraction sockets of 60 hemimandibles of veh (veh/RANKL-, veh/RANKL+) or ZA treated rats (ZA/RANKL-, ZA/RANKL+). Rats were euthanized 3 or 12 days after surgery. Animals euthanized at 12 days received two additional veh or ZA injections. Clinical, radiographic and histologic assessments were performed. Visually, at the 3-day timepoint, no sockets demonstrated complete healing. At the 12-day timepoint, sockets of veh/RANKL- and veh/RANKL+ rats showed intact mucosa, while mucosal defects were noted in ZA/RANKL- rats. Importantly, ZA/RANKL+ sockets showed absence of bone exposure. RANKL delivery increased bone healing in the ZA/RANKL+ sites 12 days after extraction compared to the ZA/RANKL- sites. Histologically, at the 3-day timepoint, ZA/RANKL- sockets demonstrated extensive bone exposure and osteonecrosis. In contrast, ZA/RANKL+ rats showed granulation tissue coverage and significantly reduced osteonecrosis, similar to the veh groups. Importantly, in the ZA/RANKL+ group, osteoclasts attached to the bone surface and osteoclast numbers were higher compared to ZA/RANKL- sites. At the 12-day timepoint, persistent osteonecrosis and bone exposure were detected in the sockets of ZA/RANKL- animals. Contrary, ZA/RANKL+ rats demonstrated socket epithelialization and reduced osteonecrosis. Significantly more total and bony attached osteoclasts persisted in the ZA/RANKL+ vs the ZA/RANKL- group. We present a novel approach towards improving socket healing, in the presence of ZA, by enhancing osteoclastic numbers and attachment through local RANKL application. Our approach is clinically applicable and could improve treatment outcomes of patients on high-dose ZA therapy.

Histomorphometric Evaluation of Socket Preservation Using Autogenous Tooth Biomaterial and BM-MSC in Dogs

This study is aimed at assessing the dimensional alterations occurring in the alveolar bone after premolar extraction in dogs with histomorphometric and histological analysis. After atraumatic premolar extraction, tooth-derived bone graft material was grafted in the extraction socket of the premolar region in the lower jaws of six dogs in two experimental groups. In the second experimental group, BM-MSCs were added together with the graft. The control was left untreated on the opposite side. After twelve weeks, all six animals were sacrificed. Differences in alveolar bone height crests lingually and buccally, and alveolar bone width at 1, 3, and 5 mm infracrestally, were examined. Histologic study revealed osteoconductive properties of tooth biomaterial. A statistically significant difference was detected between the test and control groups. In the test groups, a reduced loss of vertical and horizontal alveolar bone dimensions compared with the control group was observed. Tooth bone graft material may be considered useful for alveolar ridge preservation after tooth extraction, as it could limit the natural bone resorption process.

Efficacy of platelet-rich fibrin on bone formation, part 1: Alveolar ridge preservation

PURPOSE

To investigate the use of platelet-rich fibrin for alveolar ridge preservation compared to natural healing, bone graft material and platelet-rich fibrin in combination with bone graft material.

MATERIALS AND METHODS

The present systematic review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The review examined randomised controlled trials comparing the clinical outcomes of platelet-rich fibrin with those of other modalities for alveolar ridge preservation. Studies of third molar extraction site healing were excluded. The studies were classified into three categories: natural wound healing vs platelet-rich fibrin; bone graft material vs platelet-rich fibrin; and bone graft material vs bone graft material and platelet-rich fibrin.

RESULTS

From 179 articles identified, 16 randomised controlled trials were included. Owing to the heterogeneity of the investigated parameters, it was not possible to perform a meta-analysis. In total, 10 randomised controlled trials compared platelet-rich fibrin to natural wound healing, with seven of these demonstrating favourable outcomes to either limit postextraction dimensional changes or improve new bone formation in the platelet-rich fibrin group. Three of four studies comparing healing with bone graft material to platelet-rich fibrin found that the latter led to significantly greater horizontal or vertical bone resorption, and the bone graft material was more able to maintain the ridge dimensions. Two out of three randomised controlled trials investigating healing with both bone graft material and platelet-rich fibrin reported better outcomes using this combined approach than with bone graft material alone. All studies investigating soft tissue healing with platelet-rich fibrin demonstrated better outcomes in the platelet-rich fibrin group.

CONCLUSIONS

The majority of studies comparing healing with platelet-rich fibrin to natural healing concluded that the former more successfully limits postextraction dimensional changes than the latter. However, 75% of studies investigating platelet-rich fibrin vs bone graft material reported better results in the bone graft group with respect to its ability to maintain postextraction dimensional changes. The addition of platelet-rich fibrin to bone graft material may improve clinical outcomes, although data are limited.

Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site development

BACKGROUND

Alveolar bone changes following tooth extraction can compromise prosthodontic rehabilitation. Alveolar ridge preservation (ARP) has been proposed to limit these changes and improve prosthodontic and aesthetic outcomes when implants are used. This is an update of the Cochrane Review first published in 2015.

OBJECTIVES

To assess the clinical effects of various materials and techniques for ARP after tooth extraction compared with extraction alone or other methods of ARP, or both, in patients requiring dental implant placement following healing of extraction sockets.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 19 March 2021), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2021, Issue 2), MEDLINE Ovid (1946 to 19 March 2021), Embase Ovid (1980 to 19 March 2021), Latin American and Caribbean Health Science Information database (1982 to 19 March 2021), Web of Science Conference Proceedings (1990 to 19 March 2021), Scopus (1966 to 19 March 2021), ProQuest Dissertations and Theses (1861 to 19 March 2021), and OpenGrey (to 19 March 2021). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. A number of journals were also handsearched.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) on the use of ARP techniques with at least six months of follow-up. Outcome measures were: changes in the bucco-lingual/palatal width of alveolar ridge, changes in the vertical height of the alveolar ridge, complications, the need for additional augmentation prior to implant placement, aesthetic outcomes, implant failure rates, peri-implant marginal bone level changes, changes in probing depths and clinical attachment levels at teeth adjacent to the extraction site, and complications of future prosthodontic rehabilitation.

DATA COLLECTION AND ANALYSIS

We selected trials, extracted data, and assessed risk of bias in duplicate. Corresponding authors were contacted to obtain missing information. We estimated mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes, with 95% confidence intervals (95% CI). We constructed 'Summary of findings' tables to present the main findings and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 16 RCTs conducted worldwide involving a total of 524 extraction sites in 426 adult participants. We assessed four trials as at overall high risk of bias and the remaining trials at unclear risk of bias. Nine new trials were included in this update with six new trials in the category of comparing ARP to extraction alone and three new trials in the category of comparing different grafting materials. ARP versus extraction: from the seven trials comparing xenografts with extraction alone, there is very low-certainty evidence of a reduction in loss of alveolar ridge width (MD -1.18 mm, 95% CI -1.82 to -0.54; P = 0.0003; 6 studies, 184 participants, 201 extraction sites), and height (MD -1.35 mm, 95% CI -2.00 to -0.70; P < 0.0001; 6 studies, 184 participants, 201 extraction sites) in favour of xenografts, but we found no evidence of a significant difference for the need for additional augmentation (RR 0.68, 95% CI 0.29 to 1.62; P = 0.39; 4 studies, 154 participants, 156 extraction sites; very low-certainty evidence) or in implant failure rate (RR 1.00, 95% CI 0.07 to 14.90; 2 studies, 70 participants/extraction sites; very low-certainty evidence). From the one trial comparing alloplasts versus extraction, there is very low-certainty evidence of a reduction in loss of alveolar ridge height (MD -3.73 mm; 95% CI -4.05 to -3.41; 1 study, 15 participants, 60 extraction sites) in favour of alloplasts. This single trial did not report any other outcomes. Different grafting materials for ARP: three trials (87 participants/extraction sites) compared allograft versus xenograft, two trials (37 participants, 55 extraction sites) compared alloplast versus xenograft, one trial (20 participants/extraction sites) compared alloplast with and without membrane, one trial (18 participants, 36 extraction sites) compared allograft with and without synthetic cell-binding peptide P-15, and one trial (30 participants/extraction sites) compared alloplast with different particle sizes. The evidence was of very low certainty for most comparisons and insufficient to determine whether there are clinically significant differences between different ARP techniques based on changes in alveolar ridge width and height, the need for additional augmentation prior to implant placement, or implant failure. We found no trials which evaluated parameters relating to clinical attachment levels, specific aesthetic or prosthodontic outcomes for any of the comparisons. No serious adverse events were reported with most trials indicating that the procedure was uneventful. Among the complications reported were delayed healing with partial exposure of the buccal plate at suture removal, postoperative pain and swelling, moderate glazing, redness and oedema, membrane exposure and partial loss of grafting material, and fibrous adhesions at the cervical part of previously preserved sockets, for the comparisons xenografts versus extraction, allografts versus xenografts, alloplasts versus xenografts, and alloplasts with and without membrane.

AUTHORS' CONCLUSIONS

ARP techniques may minimise the overall changes in residual ridge height and width six months after extraction but the evidence is very uncertain. There is lack of evidence of any differences in the need for additional augmentation at the time of implant placement, implant failure, aesthetic outcomes, or any other clinical parameters due to lack of information or long-term data. There is no evidence of any clinically significant difference between different grafting materials and barriers used for ARP. Further long-term RCTs that follow CONSORT guidelines (www.consort-statement.org) are necessary.

Why do some extraction sites develop medication-related osteonecrosis of the jaw and others do not? A within-patient study assessing radiographic predictors

PURPOSE

To compare radiographic predictors of medication-related osteonecrosis of the jaw in dental extraction sites.

MATERIALS AND METHODS

Forty-one oncological patients undergoing intravenous or subcutaneous antiresorptive treatment, with a history of dental extraction visualised by panoramic imaging, were included in this retrospective study. Age-, sex- and extracted tooth-matched healthy patients who had previously undergone panoramic imaging were selected as controls (n = 57). A total of 288 extraction sites were independently evaluated by two oral and maxillofacial radiologists, who assessed eight distinct radiographic features. The radiographic features of extraction sites were noted to allow comparison between and within subjects regarding healing and osteonecrosis development. The association between radiographic findings, underlying dental disease and medication-related osteonecrosis of the jaw was also tested. The level of significance was set at 5%.

RESULTS

Patients under antiresorptive treatment presented with widening of the periodontal ligament space, thickening of the lamina dura, sclerotic bone pattern, horizontal bone loss and periapical radiolucency with bone reaction (P ≤ 0.05). Development of medication-related osteonecrosis of the jaw was associated with altered bone pattern, angular bone loss, furcation involvement and unsatisfactory endodontic treatment (P ≤ 0.05). An association between medication-related osteonecrosis of the jaw and previous dental disease was also found, particularly for periapical lesions and endodontic-periodontal disease (P ≤ 0.05).

CONCLUSIONS

Radiographic predictors of further development of medication-related osteonecrosis of the jaw in extraction sites include heterogeneous bone pattern, angular bone loss and furcation involvement. Extraction sites with underlying bony changes related to endodontic and endodontic-periodontal disease are more prone to development of medication-related osteonecrosis of the jaw.

Abnormal macrophage polarization impedes the healing of diabetes-associated tooth sockets

Patients with poorly controlled type 2 diabetes mellitus (T2DM) often experience delayed tooth extraction socket (TES) healing. Delayed healing is often associated with an aberrant inflammatory response orchestrated by either M1 pro-inflammatory or M2 anti-inflammatory macrophages. However, the precise mechanism for the attenuated TES healing remains unclear. Here we used diet-induced T2DM mice as a model to study TES. Compared with the control group, the T2DM group showed delayed TES healing and diminished expression of osteogenic and angiogenic genetic profiles. Meanwhile, we detected a more inflammatory profile, with more M1 macrophages and TNF-α expression and less M2 macrophages and PPARγ expression, in TES in the T2DM group when compared to control mice. In vitro co-culture models showed that M1 macrophages inhibited the osteogenic capacity of bone marrow stromal cells and the angiogenic capacity of endothelial cells while M2 macrophages showed an opposite effect. In addition, we constructed a gelatin/β-TCP scaffold with IL-4 to induce macrophage transformation towards M2 polarization. In vitro analyses of the hybrid scaffold revealed sustained release of IL-4 and a phenotype switch to M2 macrophages. Finally, we demonstrated that sustained IL-4 release significantly increased expression of osteogenic and angiogenic genetic profiles and improved TES healing in T2DM mice. Together, we report that increased M1 and decreased M2 macrophage polarization may be responsible for delayed TES healing in T2DM patients through abnormal expression of TNF-α and PPARγ. This imbalance negatively influences osteogenesis and angiogenesis, two of the most important biological factors in bone wound healing. Enhancing M2 macrophage polarization with IL-4 delivery system may represent a potential strategy for promoting the healing of TES in T2DM patients.

A Prospective Study Comparing the Effect of L-PRF and Porous Titanium Granules on the Preservation of the Buccal Bone Plate Following Immediate Implant Placement

The aim of this study was to compare the effect of an autogenous blood concentrate (L-PRF) with the effect of white porous titanium granules (WPTG) on buccal bone remodeling. These materials were used to graft the void between the implant and the buccal bone following immediate implant placement. Clinical measurements were made at two time points, and the mean buccal bone horizontal dimension at placement was 2.94 ± 0.59 mm for L-PRF and 3.49 ± 0.99 mm for WPTG. At reentry, the values were 1.19 ± 0.90 mm and 2.12 ± 0.87 mm, respectively. Overall, there was no difference observed in the performance of the two materials regarding buccal bone resorption.

Albumin-Impregnated Allograft Filling of Surgical Extraction Sockets Achieves Better Bone Remodeling Than Filling with Either Blood Clot or Bovine Xenograft

PURPOSE

The goal of this study was to compare bone graft materials in mandibular third molar extraction sockets and to monitor bone remodeling and complications.

MATERIALS AND METHODS

Patients with bilateral, impacted mandibular third molars were involved. Twenty-four patients were planned to be randomly assigned to three possible treatments: (1) the control sockets were left empty; (2) the socket was filled with bovine xenograft (Bio-Oss); or (3) the socket was filled with albumin-impregnated bone allograft (BoneAlbumin). Postoperative pain during the first week was determined with the visual analog scale. Cone beam computed tomography (CBCT) images were taken at 6 and 12 weeks and 1 year postoperatively for micromorphologic analysis and measurement of pocket depth at the second molar. Patients and image analyses were blinded toward the treatment group (randomized double-blind split-mouth design).

RESULTS

Postoperative pain was lowest in the allograft group (control: 5.06 ± 0.53; xenograft: 5.85 ± 0.42; allograft: 3.94 ± 0.52; P < .05). At weeks 6 and 12, early signs of remodeling were observed in the allograft group and the controls, while bone xenograft was still demarcated from the host bone. The 1-year CBCT images showed complete remodeling and integration of allograft with natural trabecular structure, while the xenograft particles were still visible. Support for the second molar was significantly better, as evidenced by less deep and prevalent pockets in the allograft-filled group compared with the controls (P = .017).

CONCLUSION

Filling an extraction socket with albumin-integrated allografts provides superior bone regeneration compared to either native bone buildup or xenograft application or socket regeneration without bone grafting.

New Classification System for Cleft Alveolus: A Computed Tomography-based Appraisal

AIM

The present study proposed a new classification system based on computed tomography (CT) scan appraisal; this enables the surgeon to identify the extent of the defect and helps to execute the proper treatment plan.

BACKGROUND

Various terminologies and classifications were proposed to understand developmental defects. But none of the existing classifications/nomenclatures used the preoperative radiographic evaluation (i.e., computed tomography scan-CT scan) in the management and prognosis. Various treatments were advocated and practiced successfully for the surgical correction of lip and palate.

MATERIALS AND METHODS

The available CT scans from archives of the Department of Radiology and Oral and Dental Surgery were evaluated (retrospectively) for cleft alveolus and its morphology as per the proposal. The English language literature was searched in the MEDLINE database without date restriction to revise existing literature on numerous classification systems/nomenclatures using MeSH keywords related to cleft lip, palate, alveolus, developmental disturbance, facial clefts, and classification. Existing classification systems were revisited with a note on the drawbacks. After careful examination of morphological patterns of all clefts, the new CT scan-based alveolar cleft classification is proposed depending on the extent of cleft.

RESULTS

The literature revealed a total of twenty-nine classifications of cleft lip and palate starting from the year 1922 to the year 2015, but none exclusively classified the cleft alveolus based on CT scan observations. The observation of three thousand CT scans showed five types of cleft alveolus, depending on the extent of involvement.

CONCLUSION

The CT scan-based classification is essential to the surgeon for successful surgical planning of cleft alveolus. The proposed classification is clinically relevant in this digital era for relating surgical outcomes. The three-dimensional viewing of a defect is essential for the surgeon for virtual planning. This paper provides a CT scan-based classification for universal acceptance in this era of digital technology, and CT scan aids in achieving these goals.

CLINICAL SIGNIFICANCE

The new proposal is based on preoperative evaluation of cleft using a CT scan. CT scan imaging provides a clear picture of the cleft in three dimensions for the operating surgeon. Advanced technology-enhanced surgical management modalities like CAD/CAM guided templates to support graft for successful management. The classification system will help the medical and surgical fraternity in various aspects. The three-dimensional modeling of defect and printing of a defect model using additive manufacturing technology helps the surgeon for presurgical visualization and virtual planning in a better way. This strategy of defect classification using a CT scan will help obtain better clinical outcomes and patient satisfaction.

Effect of Diode Low-level Laser Irradiation Time on Socket Healing

AIM

The purpose of this research was to survey the effect of low-level laser irradiation time on socket healing in rats.

MATERIALS AND METHODS

This randomized nonblinded animal study was done on 24 male rats that were divided into four groups. First maxillary molars of rats were extracted through general anesthesia, and laser was used in all four groups: first group with zero radiation time, second group with 3 minutes, third group with 5 minutes, and fourth group with 10 minutes of radiation by the diode laser (power: 100 mW, wavelength: 980 nm). Half of the rats (three rats) were sacrificed on the 3rd day and another half of rats were sacrificed on the 7th day. Then, the presence of angiogenesis, bone trabeculae, fibroblasts, neutrophil cells, macrophage cells, and lymphocyte cells was assessed. Data were analyzed by SPSS (version 21) using parametric tests.

RESULTS

Among 24 rats, on the 3rd day, the percentage of macrophage and bone trabecula increased significantly in the 5 minute group (p = 0.041 and p < 0.01, respectively). Other changes in days 3 and 7 were not statistically significant (p > 0.05).

CONCLUSION

Low-level laser radiation can accelerate the process of tooth socket healing, which was particularly noticeable in the 5 minute radiation over 3 days.

CLINICAL SIGNIFICANCE

Using a low-level laser can be helpful in accelerating the healing of the tooth socket and reduce the complications after tooth extraction.

Tapered Versus Inverted Body-Shift Implants Placed Into Anterior Post-extraction Sockets: A Retrospective Comparative Study

BACKGROUND

A retrospective comparative radiographic and clinical studywas performed to evaluate primary stability, bone volume, and esthetic outcomes of tapered (T) implants (control group) versus inverted body-shift (INV) implants (test group).

METHODS

A total of 42 platform-switched implants, 21 T and 21 INV, were used to replace nonrestorable teeth in maxillary central incisor post-extraction sockets. Implant primary stability and insertion torque values in addition to radiographic differences in labial plate dimension, tooth-to-implant distance, and marginal bone levels were correlated with clinical outcomes using the pink esthetic score (PES).

RESULTS

Statistically significant differences (P ≤ .05) were found between groups, with T implants having not only lower primary stability at immediate implant placement than INV implants but also less circumferential bone volume at recall. Consequently, lower PESs were seen in the T implant group that equated to an increased frequency of midfacial recession, tissue discoloration, and papilla loss.

CONCLUSIONS

INV implants, which feature a unique macro hybrid design, may offer advantages over T implants in maxillary anterior post-extraction sockets with regard to achieving both higher primary stability and superior esthetic outcomes.

Clinical Outcomes of Maxillary Anterior Postextraction Socket Implants with Immediate Provisional Restorations Using a Novel Macro-Hybrid Implant Design: An 18- to 24-Month Single-Cohort Prospective Study

Extraction and immediate implant placement/restoration in the esthetic zone is clinically challenging; benefits include fewer surgical appointments and maintenance of peri-implant soft tissues throughout the treatment period, and limitations include gingival recession and bone dehiscence during surgery. Macro-hybrid implants (large-diameter apical/narrow-diameter occlusal) were placed in 19 patients immediately following the extraction of hopeless maxillary anterior teeth. Immediate restorations were fabricated without occlusal contacts. Pre- and postplacement cone beam computed tomography (CBCT) scans were taken. Nineteen implants were available for recall 13 to 25 months postoperatively. The overall implant cumulative survival rate was 100% (range: 13 to 25 months, mean: 19 months), and mean insertion torque value was 65 Ncm. Mean Pink Esthetic Score was 12.63 at 6 months, and was 13 at the 18- to 24-month follow-up. Mean mesial and distal tooth-to-implant distances immediately after implant placement were 2.55 ± 1.29 mm and 2.29 ± 0.82 mm, respectively. Interproximal bone crest width, distance, and height were maintained at implant platforms, mesially and distally, 18 to 24 months postoperative. The results of this study indicated that the macro-hybrid implant geometry for this immediate surgical/restorative protocol provided excellent and stable 2-year results relative to implant survival (100%), labial plate thickness via CBCT evaluations, tooth-to-implant distances immediately post-implant placement, PES, and interproximal bone crest width, distance, and heights, which were maintained at the implant platforms.

Complication Management of a Socket Shield Case After 6 Years of Function

Maintaining soft and hard tissues around dental implants after tooth extraction is one of the major challenges in implant dentistry. After tooth extraction, the subsequent loss of bone and soft tissue is inevitable due to the partial resorption of the buccal bone plate. The recently described socket shield technique addresses the problem by maintaining the buccal piece of the tooth in the extraction socket in order to preserve the buccal bone. As with every new technique, specific complications, like infection of the buccal piece of the tooth, can occur. Herein, the authors present a clinical case that developed a complication with the socket shield technique and the consequential surgical management.

A Comparison of the Effect of Barrier Membranes on Clinical and Histologic Hard and Soft Tissue Healing with Ridge Preservation

Twenty patients completed this randomized, controlled, blinded clinical trial comparing ridge preservation with a bioabsorbable polylactic acid membrane (PLA group) compared to an acellular dermal matrix membrane guided bone regeneration (ADMG group). An intrasocket corticocancellous allograft plus a facial overlay xenograft was used for both groups. Final crestal ridge width was significantly greater for the ADMG group (P < .05). Soft tissue thickness, conversely, was thicker for the PLA group. Vertical ridge height change increased significantly for the midbuccal site of the ADMG group. Histologic evaluation showed high percentages of vital bone for both groups.

[Application of computer virtual design to assist the accuracy of socket preparation during tooth autotransplantation]

PURPOSE

It was aimed to apply computer virtual design and digital surgical templates to simulate postoperative position of tooth and guide the accuracy of socket preparation during tooth autotransplantation.

METHODS

The study enrolled 10 patients who underwent tooth autotransplant surgery. Cone-bean CT (CBCT) data were imported into Proplan CMF 3.0 software. The donor tooth was transferred to the recipient site according to the occlusion and space situation. A digital template was designed to guide socket preparation. Computer-aided rapid prototyping (RP) technique was used to print the surgical template and tooth model.

RESULTS

With computer virtual design and digital template, it was possible to accurately guide socket preparation in recipient site. The six-month follow-up results showed the periodontal space in the radiographs was continuous and intact. There was no mobility in all cases and the probing depth of the tooth was <4 mm. The related data showed a favorable survival and success rates of the donor teeth.

CONCLUSIONS

Computer virtual design can successfully simulate postoperative position in tooth autotransplantation while simplifying the surgical procedure, and enhance the accuracy of socket preparation.

A decade of the socket-shield technique: a step-by-step partial extraction therapy protocol

Ten years have passed since Hürzeler and coworkers first introduced the socket-shield technique. Much has developed and evolved with regard to partial extraction therapy, a collective concept of utilizing the patient's own tooth root to preserve the periodontium and peri-implant tissue. The specifications, steps, instrumentation, and procedures discussed in this article are the result of extensive experience in refining the socket-shield technique as we know it today. A repeatable, predictable protocol is requisite to providing tooth replacement in esthetic dentistry. Moreover, a standardized protocol provides a better framework for clinicians to report data relating to the technique with procedural consistency. This article aims to illustrate a reproducible, step-by-step protocol for the socket-shield technique at immediate implant placement and provisionalization for single-rooted teeth.

Outcome of Treatment with Single Implants in Preserved Versus Nonpreserved Alveolar Ridges: A 1-year Cohort Study

PURPOSE

To evaluate the effect of placement of single implants in the esthetic zone of the maxilla in preserved alveolar ridges, compared with nonpreserved alveolar ridges, on the change in midlabial mucosal level, esthetics, marginal bone level, and patient satisfaction.

MATERIALS AND METHODS

Patients with a failing single tooth, and demonstrating a large vertical defect (≥ 5 mm) of the labial wall of the extraction socket, were pre-augmented with a mixture of autologous bone and anorganic bovine bone. A mucosal graft sealed the pocket. After 4 months, a single implant was placed in the preserved alveolar ridge (test group; n = 20). The results were compared with those from patients who had one missing tooth and were treated with placement of an implant in a nonpreserved alveolar ridge, whereby the connective tissue graft was combined with the placement of the implant (control group; n = 20). Changes in midlabial mucosal level were scored on intraoral images. Intraoral radiographs were made to assess marginal bone level changes after definitive crown placement (1 month [T₁], 12 [T₁₂] months). The pink esthetic score/white esthetic score at T₁₂ was used to determine esthetics. Patient satisfaction was assessed before treatment (T_pre), and at T₁ and T₁₂.

RESULTS

The mean midlabial mucosal level changes were 0.07 ± 0.29 mm and -0.15 ± 0.23 mm at T₁ and T₁₂ for the control and test groups, respectively (P = .01). No significant changes were observed for the other outcome variables.

CONCLUSION

Single implant treatment in a preserved alveolar ridge and nonpreserved alveolar ridge is accompanied by clinically nonrelevant changes in the midlabial mucosal level. Changes in marginal bone level, esthetics, and patient satisfaction were comparable between the groups.

Effect of platelet-rich fibrin on alveolar ridge preservation: A systematic review

BACKGROUND

Platelet-rich fibrin (PRF) is the second generation of platelet concentrates and is used in many areas of dentistry. However, whether PRF is effective for alveolar ridge preservation remains controversial. The authors conducted research to evaluate the potential of PRF to preserve the alveolar ridge.

METHODS

A comprehensive literature search was conducted in MEDLINE, Cochrane Central Register of Controlled Trials, and Embase. Only randomized controlled trials were included. A systematic review was made for postoperative pain, soft-tissue healing, bone density, horizontal and vertical ridge dimension changes, and histologic analysis. The meta-analysis was performed on the alveolar osteitis, mesial and distal bone height changes, and bone fill with Review Manager Version 5.3 software.

RESULTS

Among the 588 eligible articles found in the initial search, 7 published studies from 2012 through 2019 were included. The authors' qualitative analysis showed that PRF may play a positive role in reducing postoperative pain and ridge dimension changes after tooth extraction. Among the 7 articles, only 2 trials assessed the effect of PRF on the alveolar osteitis, mesial and distal bone height changes, and bone fill. Results of our meta-analysis showed that smaller mesial bone height changes (standard mean difference, -1.07; 95% confidence interval, -1.92 to 0.22) and a greater percentage of bone fill (standard mean difference, 0.82; 95% confidence interval, 0.32 to 1.33) were observed in the PRF group.

CONCLUSIONS

Given the potential value of PRF, consideration should be given to PRF after tooth extraction. However, more high-quality trials are necessary to evaluate the exact role of PRF.

PRACTICAL IMPLICATIONS

Based on the authors' results, the usage of PRF was suggested in alveolar ridge preservation.

The Influence of Implant Neck Features and Abutment Diameter on Hard and Soft Tissues Around Single Implants Placed in Healed Ridges: Clinical Criteria for Selection

The clinician's selection of an implant system is influenced by many variables. Ideally, the decision should be based on scientific evidence, but often these decisions are based on economic considerations or influenced by the experience of a trusted peer. The purpose of this paper is to describe the influence of implant neck features (shape and surface) and abutment connection (diameter that matches or is smaller than the implant's platform) on hard and soft tissues around single-tooth implants placed into healed ridges with adequate hard and soft tissue thickness. In an effort to reduce the number of variables, only two-piece implants fully placed at bone level or beneath were taken into consideration. The goal is to provide additional guidance for clinicians on the decision-making and implant-selection processes.

Orthodontic extraction space closure with and without socket preservation: a comparative case analysis

Preorthodontic socket preservation after tooth extraction is intended to enhance favorable dentoalveolar ridge morphology and architecture, and facilitate orthodontic tooth movement (OTM) and extraction space closure. This 13-year-old skeletal Class II case presents a unique opportunity to evaluate and compare the OTM extraction space closure by means of a split-mouth analysis in a single patient. The comprehensive orthodontic-periodontal treatment included nonsimultaneous extraction of the bilateral periodontally compromised mandibular first molars and the eruption of bilateral impacted mandibular canines. While the right post-extraction space underwent a natural healing process, the left one was grafted using 4BONE BCH (hydroxyapatite β-tricalcium phosphate [HA-β-TCP], HA 60%, and β-TCP 40%). The 3-year multidisciplinary treatment approach resulted in Class I relationships on the right side and Class II on the left side, improved facial appearance, and dento-skeletal jaw relationships. However, a 3-mm residual alveolar space remained unclosed on the grafted left-site, along with an unerupted left third molar. This split-mouth comparative analysis of the orthodontic space closure demonstrated a significant clinical difference in the outcome. Preorthodontic placement of HA-β-TCP grafting material on the left segment, proved to be an obstacle for OTM extraction space closure, hindering the establishment of good occlusion.

Evidence Is Unclear About the Best Material and Technique Required for Alveolar Ridge Preservation for Dental IMPLANT SITE Development

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site development. Atieh MA, Alsabeeha NH, Payne AG, Duncan W, Faggion CM, Esposito M. Cochrane Database Syst Rev 2015. https://doi.org/10.1002/14651858.CD010176.pub2.

SOURCE OF FUNDING

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

[Preliminary study on true bone ceramics for alveolar ridge preservation in dogs]

OBJECTIVE

To study the preservation effect of true bone ceramics (TBC) prepared by high-temperature calcination of bovine bone on alveolar ridge of canine extraction socket.

METHODS

Six healthy Beagle dogs (aged 1.5-2 years) were selected to extract the second and fourth premolars of both mandibles and the second premolars of the maxilla. The left extraction socket was implanted with TBC as the experimental group, and the right side was implanted with the calcined bovine bone (CBB) as the control group, to observe the alveolar ridge preservation effect. Three dogs were euthanized after general observation at 1 and 6 months after operation respectively. After separating the maxilla and mandible, cone beam CT (CBCT) was performed to measure the average gray value of the graft site and the adjacent reference area (the area between the roots of the adjacent third premolar) and calculate the gray scale ratio between the bone graft site and the reference area. Histological observation was made on the bone graft site to evaluate the new bone formation.

RESULTS

General observation showed that the wounds of both groups were basically healed at 2 weeks after operation, and the bone graft materials were not exposed. The wounds healed well at 1 and 6 months after operation without swelling. The results of CBCT showed that the residual material was found in both groups at 1 month after operation, and no significant residual material was found in both groups at 6 months after operation, and the alveolar ridge height of the bone graft area was not significantly reduced. There was no significant difference in the bone mineral density between the experimental group and the control group. The gray scale ratios of the experimental group at 1 month and 6 months after operation were 0.97±0.14 and 0.93±0.06, respectively, and were 0.99±0.16 and 0.94±0.05 in control group, showing no significant difference between the two groups ( t=-1.030, P=0.333; t=-0.770, P=0.466). HE staining observation showed that a large number of bone graft materials did not degrade and new bone formed around the grafts in both groups at 1 month after operation; the bone graft materials were absorbed and a large number of new bones were formed in both groups at 6 months after operation.

CONCLUSION

TBC can maintain bone mineral density and have good osteoconductivity in the alveolar ridge site preservation experiment of dogs, and can be used for alveolar ridge site preservation.

Customized vs Conventional Implant-Supported Immediate Provisional Crowns for Fresh-Socket Implant: A Medium-Term Cone Beam Computed Tomography Study

PURPOSE

To measure the volume effect on maintaining a sealing around immediately rehabilitated dental implants in a comparison between customized and conventional provisional crowns at a 3-year follow-up.

MATERIALS AND METHODS

A single crown supported by a dental implant was used as a rehabilitation strategy for a failing tooth. The primary predictor was the type of immediate restoration with custom or conventional provisional crowns; a secondary predictor was tooth position: incisor, canine, or premolar. In order to accurately measure the width between buccal and palatal plates at the alveolar margin in a comparison between preoperative (before tooth extraction) and postoperative (at the 3-year follow-up) radiographs, two cone beam computed tomography (CBCT) scans were three-dimensionally analyzed and superimposed.

RESULTS

Seventy-six patients, rehabilitated with single implants, were selected (31 implants belonging to the custom group and 45 to the conventional group). In patients treated with conventional restorations, a significant shrinkage (-0.6 ± 1.2 mm with P = .002) was registered. On the other hand, the bone change registered for the custom restoration group appeared negligible, with a nonsignificant and slight increase in width (+0.2 ± 0.7 mm). When the subgroups regarding the implant sites were investigated, the decrease in width was very limited for the canine tooth in the custom group (-0.3 ± 0.2 mm), whereas the shrinkage at the canine in the standard group appeared to be significantly higher (-1.5 ± 0.7 mm with P = .0001).

CONCLUSION

An anatomically contoured provisional restoration may provide a strategy to stimulate peri-implant soft tissue healing, minimize loss of buccal bone plate at the marginal level, and maintain pristine volume in the alveolar bone better than noncustomized restorations.

Ridge preservation in molar extraction sites with an open-healing approach: A randomized controlled clinical trial

AIM

To determine the effect of alveolar ridge preservation (ARP) in molar sites without primary flap closure.

MATERIALS AND METHODS

Three groups were established: extraction sockets grafted with deproteinized bovine bone mineral containing 10% collagen (DBBM-C) and covered by a native bilayer collagen membrane (NBCM) (test group 1), sockets grafted with DBBM-C only (test group 2), and sockets that healed naturally (control group). Primary flap closure was not attempted. Conebeam computed tomography scans were obtained immediately and then 4 months after ARP. A biopsy was performed. The change of the marginal bone level was measured.

RESULTS

There was significantly less horizontal resorption in test group 1 than in the control group at levels 1 mm (-1.02 ± 0.88 [mean ± SD] vs. -4.44 ± 3.71 mm) and 3 mm (-0.31 ± 1.51 vs. -2.27 ± 1.15 mm) below the crest, and significantly less vertical reduction in the midcrestal area in test group 1 than in test group 2 (-0.25 ± 0.95 vs. -1.15 ± 1.63 mm) (p < .05). There were no significant differences between test groups in clinical and histomorphometric measurements. All groups exhibited stable marginal bone levels after 1 year of loading.

CONCLUSION

Alveolar ridge preservation without primary flap closure in molar areas was effective in minimizing ridge resorption and facilitated implant treatment.

Efficacy of PRF vs PRF + Biodegradable Collagen Plug in Post-extraction Preservation of Socket

AIM

To compare the clinical sequelae of the efficacy of PRF vs PRF + collagen plug in soft tissue healing and preservation of the socket width, height, and bone density in patients reporting for extractions of maxillary or mandibular anterior or posterior teeth and patients who desired replacement of teeth with dental implants in future.

MATERIALS AND METHODS

The study included 54 patients who were divided randomly into 3 groups consisting of 18 patients in each group: in group I, no preservation of extraction socket; in group II, PRF was used; and in group III, PRF + collagen plug was used for preservation of extraction socket. Assessment of the soft tissue healing, bone density, bone height, and width was done on 1st, 8th, 12th, and 16th weeks, postoperatively.

RESULT

Both PRF and PRF + Collaplug are comparable to each other in preserving the bone height, bone density, and also similar soft tissue healing; however PRF + Collaplug is better than PRF alone in preserving the bone width 4th month postoperatively, indicating that the resorbable Collaplug® does play an additional role in preserving the socket width.

CONCLUSION

PRF + Collaplug® has better clinical outcome in socket preservation in comparison to PRF alone. However, as results were not statistically significant, subjecting a larger sample size with PRF + Collaplug® for socket preservation may result in statistical critical values to substantiate our observations.

CLINICAL SIGNIFICANCE

PRF and Collaplug® can help in ridge preservation after extraction and also avoid additional bone grafting procedures in future implant placement for the patients. How to cite this article: Ahmed N, Gopalakrishna V, Shetty A, et al. Efficacy of PRF vs PRF + Biodegradable Collagen Plug in Post-extraction Preservation of Socket. J Contemp Dent Pract 2019;20(11):1323-1328.

Hard and soft tissue changes in the rehabilitation of the anterior maxilla with triangular shape neck implants: a retrospective clinical study with a one-year follow up

Aim of this retrospective study was to evaluate the one-year clinical and radiographic outcomes of implants with a triangular shaped neck inserted immediately after tooth extraction in esthetic zones. Patients in which immediate postextraction implants were placed and restored in the anterior maxilla, who underwent a Cone Beam Computed Tomograpy (CBCT) at baseline and after 12-16 months were included. The socket was preserved using deproteinized bovine bone to fill the buccal gap, and a resorbable collagen membrane. One-year implant survival and prosthesis success were evaluated. Hard and soft tissue stability was assessed by measuring various parameters on CBCT images. Clinical evaluation was also performed and Pink Esthetic Score (PES) assessed. Data from baseline and one-year follow-up were statistically compared using paired tests and a significance threshold of p=0.05. Twenty patients (13 males, 7 females, mean age 50.42±11.35 years) were included. Each contributed with one implant. No implant was lost. A significant improvement in PES was detected. Excellent hard and soft tissue preservation was observed after one year of function. Immediate placement of implants with a triangular shaped neck after tooth extraction, can be a suitable solution even for areas with a high aesthetic demand, such as the anterior maxilla.

Autologous tooth graft: a histological comparison between dentin mixed with xenograft and dentin alone grafts in socket preservation

The aim of this study is to compare the histological results after socket preservation between dentin mixed with xenograft and dentin alone in tooth graft procedure. Six patients were included in this prospective case series study and treated in three clinical centers using standardized clinical procedures. This clinical trial enrolled patients with three walls post-extractive defects requiring the restoration of bone dimension and shape in mandibular zone. The patients were divided in two groups: extracted teeth alone (first group) and extracted teeth mixed with equal quantity of xenograft (second group). The extracted tooth was cleaned and processed by a recently introduced automated device, that allows fragmentation and partial demineralization of the tooth matrix and used as graft material. The graft obtained in this way, was inserted at the time of the extraction. A covering membrane was used to protect the graft. Implants were placed after 4 months of healing. Bone biopsies of the all grafted sites were taken at the time of implant surgery, for histological analysis. Descriptive statistics was used to synthesize the results, using mean values and standard deviations. Six patients (5 women, mean age at surgery 50.3±12.1 years) were treated and after 4 months of healing both groups, grafts height appeared stable. No signs of infection were present. Bone biopsy were taken in all grafted sites (3 with group one and 3 with group two). The histologic analysis revealed no inflammatory or infective reaction against both groups. The histomorphometry results between the two groups are different. The first group show an amount of new bone greater than the second group (+85.29%) and minor quantity of residual graft (-83.59%). The dentin alone shows a larger amount of new bone.

Healing of the post extractive socket: technique for conservation of alveolar crest by a coronal seal

The first aim of the following experimental study was to assess bone changes in the horizontal and vertical dimension when using different socket preservation procedures. The second objective of our work was also to compare two clinical methods of coronal seal's management: an experimental group was treated using the natural extracted tooth; another experimental group saw the use of a provisional resin preformed as a seal technique. In twelve patients a premolar tooth was extracted without elevation of a mucoperiosteal flap and the patients were randomly distributed into four groups. The first and second group was considered as a control groups: in the first, the extraction socket was left with its blood clot and interrupted sutures were applied; In the second, the extraction socket was filled with BioOss Collagen (Geistlich Biomaterials, Wolhusen, Switzerland) and a free gingival graft was sutured to cover the socket. The third and fourth groups was considered as a test group. In the third group, after tooth extraction, for aesthetic reasons, the root of the natural dental element is cut to allow immediate temporary prosthesis. In the fourth group, as in group 3, the patient is discharged through a temporary restoration performed or by the dental technician or directly to the chair. Standardized photographs were taken eight months after tooth extraction. Five competent observers analyzed the esthetic outcome according to the PES. To assess the level of bone healing at the extraction site, the following parameters were evaluated: 1) changes in soft tissue and 2) changes in bone level. As for soft tissues, they were assessed using the PES score by two assessments, four weeks apart. The overall scores of the four treatment groups revealed PES values of 8.47 (SD 2.08, group 3), 6.62 (SD 3.24, group 4). The differences between groups 1 and 2 and were statistically significant (P=0.015 and P=0.047). The single parameter analysis displayed a certain range of fluctuation and heterogeneity. As regards hard tissue, during the 6-month period, bone remodeling occurred in all four experimental groups with different percentages. The mean vertical loss of the buccal bone plate for the Tx 1 group was -2 ± 0.2 mm. The Tx 2 group showed vertical loss of - 0.34 ± 0.2 mm. The Tx 3 group demonstrated - 0.3 mm of mean vertical loss and the 4 groups demonstrated -0.46 of mean vertical loss. The horizontal dimension of the alveolar process was 13.5 ± 0.1 mm, 7.6 ± 0.1 mm e 6.7 ± 0.1 mm at the three different levels for the Tx 1 group. The Tx 2 group depicted bone dimensions of 14.4 ± 0.2 mm, 13.7 ± 0.3 mm e 13.4 ± 0.1 mm. The horizontal dimension of the Tx 3 - Tx 4 group was 13.7 ± 0.3 mm, 13.1 ± 0.1 mm e 13 ± 0.1 mm and 13.5 ± 0.1 mm, 13.2 ± 0.1 mm e 12.9 ± 0.1 mm. The findings from the present study disclose that incorporation of coronal seals define a particular respect to the buccal bone plate.

Choice of the treatment method of the inflammatory process in the alveolar tooth socket

INTRODUCTION

Alveolitis – is one of the most common complications in surgical dentistry after tooth extraction and their roots, accompanied by symptoms, the leading of which are pain in the alveoli with irradiation and partial or complete decay of the blood clot. The aim of our research is to study the clinical efficacy of antihomotoxic drugs and colloidal silver in patients with inflammatory processes in the alveolar tooth socket.

MATERIAL AND METHODS

58 patients with inflammatory process in the alveoli after extraction of teeth or their roots (38 - female, 20 - male), aged 18-60 years, were examined with the help of clinical and microbiological, cytological study. The main group consisted of 38 patients who were prescribed complex drug therapy after diagnosis of alveolitis. 20 patients were referred to the control group where allopathic treatments were used.

RESILTS

The main observation group in 93% ± 0.07% of patients with serous form alveolitis already on the 2nd day disappear pain, redness, swelling of the soft tissues. Gradually, the function of the mandible and the temperature response were restored. In purulent alveolitis, the function of the jaw was restored on days 3 and 4. Patients in the control group experienced a slow course of the inflammatory process in the wound, a late decrease in local pain response, swelling and hyperemia of the wound edges. Jaw function recovery averaged 3.4 ± 0.1 days longer.

CONCLUSIONS

The complex effect of drug and surgical treatment of alveolitis was studied. The combined use of colloidal silver, Traumeel® S, Polymic®, makes it possible to eliminate the inflammatory process in the alveoli faster and to reduce the period of active disease up to 2 - 3 days.