Dimension and Structures of Biological Seal of Peri-Implant Tissues

Over the years, improved understanding of the nature of bone-implant interface is among the important contributors to the success of osseointegration in modern dental implantology. The focus has since shifted to the assessment of the soft tissue-implant interface to better understand the mechanism of biological seal in the transmucosal region. The importance of peri-implant mucosal region lies in the need to establish a tight seal that isolates implant and the bone from the oral environment via epithelial and connective tissue attachment, thus preventing ingrowth of bacterial plaque. Many factors may influence the soft tissue attachment at this peri-implant interface. In this chapter, the dimension of peri-implant tissues and the factors affecting the biological seal, namely surface topography and physicochemical properties, are discussed. The review also looks into the impact of the type of materials and surface modifications of dental implant, all of which may influence the formation of biological seal of soft tissue around the dental implant

Sinteran hidroksiapatit dalam atmosfera nitrogen untuk peningkatan sifat mikrokekerasan

Hidroksiapatit (HA) adalah sejenis kalsium fosfat yang merupakan komposisi kepada kebanyakan fasa mineral tulang dan enamel gigi. HA bersifat bioserasi dan berkonduksi osteo selain mempunyai afiniti biologi dan kimia yang bagus untuk tisu tulang. Dengan ciri tersebut, HA diguna secara luas sebagai graf tulang dan bahan salut bagi implan tisu keras manusia. Walau bagaimanapun, kerapuhan dan keliatan patah yang rendah HA tersinter menghadkan penggunaannya dalam aplikasi bebanan yang tinggi. Kajian ini tertumpu kepada mengenal pasti kesan atmosfera sinteran dengan gas nitrogen (N2) ke atas sifat mekanik HA untuk aplikasi pergigian. Serbuk nano HA dicirikan dengan menggunakan mikroskop elektron pancaran. Cakera silinder HA dihasilkan dengan kaedah penekanan ekapaksi. Kemudian, cakera silinder HA dikenakan tekanan isostatik sejuk dan disinter dalam dua atmosfera sinteran yang berbeza iaitu sinteran dalam gas N2 dan sinteran dalam udara pada suhu 1300°C. Ketumpatan, mikrostruktur, kestabilan fasa dan mikrokekerasan HA tersinter dicirikan. Secara keseluruhan, sinteran dengan menggunakan gas N2 menyebabkan pertumbuhan saiz butiran yang lebih besar dengan ketumpatan relatif dan mikrokekerasan yang lebih tinggi jika dibandingkan dengan atmosfera sinteran dalam udara. Dalam kajian ini, HA yang disinter dengan menggunakan gas N2 pada suhu 1300°C menunjukkan mikrostruktur yang lebih tumpat, ketumpatan relatif (94%) dan mikrokekerasan (4.07 GPa) yang lebih tinggi jika berbanding dengan sinteran dalam udara tanpa penguraian HA. Kesimpulannya, penggunaan atmosfera sinteran dengan menggunakan gas N2 pada suhu 1300°C dapat meningkatkan sifat kekerasan Vickers nanokomposit HA dengan mikrostruktur yang padat

Susuk: di antara penemuan klinikal dan amalan tradisional

Susuk, atau dikenali sebagai ‘jarum pesona’ dipakai di muka dan bahagian badan yang lain kerana ia dipercayai dapat meningkatkan kecantikan dan keremajaan serta untuk kelihatan ‘garang’ atau tujuan merawat kesakitan tubuh badan, adalah merupakan amalan yang berdasarkan kepercayaan tradisional. Kebiasaannya, penemuan susuk secara klinikal adalah dengan tidak sengaja dalam pengimejan diagnostik, diagnostik iaitu x-ray atau computed tomography scan (CT scan), prosedur yang dijalankan untuk membantu mendiagnos sesuatu penyakit. Penemuan susuk secara kebetulan ini menimbulkan isu yang perlu dijelaskan. Dalam konteks ini, kami ingin menyelidik penggunaan susuk dan aspek-aspek lain yang berkaitan termasuk membincangkan pandangan Islam mengenai praktis ini. Pencarian sistematik telah dijalankan melalui empat pangkalan data elektronik: Ovid, Scopus, PubMed dan Embase, berdasarkan garis panduan PRISMA-ScR sehingga Jun 2023 menggunakan kata kekunci susuk di mana kriteria pemilihan adalah mana-mana artikel yang menerangkan susuk sebagai jarum lurus tanpa menghadkan masa penerbitan. Sejumlah 31 artikel telah dimasukkan dalam kajian skop ini. Kajian ini memberikan maklumat yang relevan dan berpotensi untuk memperkayakan pemahaman tentang susuk dan pengetahuan dalam pelbagai bidang seperti antropologi budaya, sains perubatan dan agama, serta mempromosikan dialog antara bidang ini

A combined management of a rare case of a maxillary lateral incisor with accessory root and deep mesio-radicular groove

This case report describes the combined nonsurgical endodontic retreatment and surgical intervention of a failed root canal treatment associated with a maxillary lateral incisor with an accessory root and deep mesio-radicular groove. A 42-year-old female Malay patient presented with persistent infection associated with deep mesial pocket from her maxillary left lateral incisor (#22). The medical history was noncontributory and the tooth was previously root treated. Following comprehensive clinical and radiographic examination, a combined nonsurgical endodontic retreatment and surgical management of tooth #22 were carried out. The inability to debride the periodontal defect necessitates the amputation of the accessory root, and surgical debridement of the deep radicular groove was carried out. The clinical and radiographic examination 1 year after completion of treatment revealed evidence of healing. The early recognition of root and canal variation, correct diagnosis, and appropriate management of tooth with accessory root and deep radicular groove is essential to ensure favorable treatment outcome

Clinical Efficacy of Single Application Local Drug Delivery and Adjunctive Agents in Nonsurgical Periodontal Therapy: A Systematic Review and Network Meta-Analysis

This review aimed to rank the clinical efficacy of commercially available single-application local drug delivery and adjunctive agents (LDAs) compared with subgingival mechanical debridement (SMD) in nonsurgical periodontal therapy (NSPT). Randomized controlled clinical trials that compared LDAs against SMD alone or with placebo in adults (aged at least 18 years) diagnosed with periodontitis with a minimum of 6 months follow-up were included. A frequentist approach to random-effects network meta-analysis was implemented. The efficacies of the LDAs measured by probing pocket depth (PPD) reduction and clinical attachment level (CAL) gain were reported as mean difference (MD) with 95% confidence intervals (CIs). The treatments were ranked according to their P-score. Four network meta-analyses suggested that sulfonic/sulfuric acid gel (PPD MD −1.13 mm, 95% CI −1.74 to −0.53, P-score 0.91; CAL MD −1.09 mm, 95% CI −1.58 to −0.61, P-score 0.95) and doxycycline hyclate gel (PPD MD −0.90 mm, 95% CI −1.50 to −0.30, P-score 0.93; CAL MD −0.84 mm, 95% CI −1.40 to −0.28, P-score 0.92) were the most effective in reducing PPD and gaining CAL in split-mouth and parallel studies, respectively (moderate certainty of evidence). LDAs have differing efficacies, but they present with possible clinical significance over SMD alone in NSPT

Clinical Efficacy of Repeated Applications of Local Drug Delivery and Adjunctive Agents in Nonsurgical Periodontal Therapy: A Systematic Review

The aim of this systematic review is to compare the clinical efficacy of repeated applications of local drug delivery and adjunctive agents (LDAs) in nonsurgical periodontal therapy (NSPT) compared to subgingival mechanical debridement (SMD) alone. The Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, EMBASE, Web of Science, hand-searched literature and grey literature databases were searched for randomized controlled clinical trials (RCTs) with a minimum of 6-month follow-up. The outcomes of interest were changes in probing pocket depth and clinical attachment level as well as patient-centred outcomes. Of 1094 studies identified, 16 RCTs were included in the qualitative analysis. Across 11 different adjuncts analysed, only two studies utilizing minocycline gel/ointment and antimicrobial photodynamic therapy (aPDT) with indocyanine green photosensitizer had statistically significant differences in primary outcomes when compared to their control groups. Only one study on aPDT methylene blue 0.005% had compared single versus multiple applications against its control group. A mean range of 0.27–3.82 mm PD reduction and −0.09–2.82 mm CAL gain were observed with repeated LDA application. Considerable clinical heterogeneity and methodological flaws in the included studies preclude any definitive conclusions regarding the clinical efficacy of repeated LDA applications. Future RCTs with a direct comparison between single and repeated applications should be conducted to confirm or refute the clinical advantages of repeated LDA application in the nonsurgical management of periodontitis

3D-Printed Hydroxyapatite and Tricalcium Phosphates-Based Scaffolds for Alveolar Bone Regeneration in Animal Models: A Scoping Review

Three-dimensional-printed scaffolds have received greater attention as an attractive option compared to the conventional bone grafts for regeneration of alveolar bone defects. Hydroxyapatite and tricalcium phosphates have been used as biomaterials in the fabrication of 3D-printed scaffolds. This scoping review aimed to evaluate the potential of 3D-printed HA and calcium phosphates-based scaffolds on alveolar bone regeneration in animal models. The systematic search was conducted across four electronic databases: Ovid, Web of Science, PubMed and EBSCOHOST, based on PRISMA-ScR guidelines until November 2021. The inclusion criteria were: (i) animal models undergoing alveolar bone regenerative surgery, (ii) the intervention to regenerate or augment bone using 3D-printed hydroxyapatite or other calcium phosphate scaffolds and (iii) histological and microcomputed tomographic analyses of new bone formation and biological properties of 3D-printed hydroxyapatite or calcium phosphates. A total of ten studies were included in the review. All the studies showed promising results on new bone formation without any inflammatory reactions, regardless of the animal species. In conclusion, hydroxyapatite and tricalcium phosphates are feasible materials for 3D-printed scaffolds for alveolar bone regeneration and demonstrated bone regenerative potential in the oral cavity. However, further research is warranted to determine the scaffold material which mimics the gold standard of care for bone regeneration in the load-bearing areas, including the masticatory load of the oral cavity

In Vitro and In Vivo Biological Assessments of 3D-Bioprinted Scaffolds for Dental Applications

Three-dimensional (3D) bioprinting is a unique combination of technological advances in 3D printing and tissue engineering. It has emerged as a promising approach to address the dilemma in current dental treatments faced by clinicians in order to repair or replace injured and diseased tissues. The exploration of 3D bioprinting technology provides high reproducibility and precise control of the bioink containing the desired cells and biomaterial over the architectural and dimensional features of the scaffolds in fabricating functional tissue constructs that are specific to the patient treatment need. In recent years, the dental applications of different 3D bioprinting techniques, types of novel bioinks, and the types of cells used have been extensively explored. Most of the findings noted significant challenges compared to the non-biological 3D printing approach in constructing the bioscaffolds that mimic native tissues. Hence, this review focuses solely on the implementation of 3D bioprinting techniques and strategies based on cell-laden bioinks. It discusses the in vitro applications of 3D-bioprinted scaffolds on cell viabilities, cell functionalities, differentiation ability, and expression of the markers as well as the in vivo evaluations of the implanted bioscaffolds on the animal models for bone, periodontal, dentin, and pulp tissue regeneration. Finally, it outlines some perspectives for future developments in dental applications

Contour Analysis of Three-Dimensional Peri-Implant Mucosal Model as an Endpoint Analysis of Photofunctionalization Effects on Implant Abutment Materials

Introduction: The objective of this study was to examine the effect of photofunctionalization on the soft-tissue contour formed at the interface of various abutment materials using end-point analyses obtained from the three-dimensional oral mucosal model (3D-OMMs). Methods: Commercially pure titanium (CPTi), alumina-toughened zirconia (ATZ), and yttria-stabilized zirconia (YSZ) made into discs shapes were classified into two groups: UV-treated (PTx) and non-treated (NTx). The materials in PTx groups were exposed to UV light for 12 min. Human gingival fibroblasts and TR146 epithelial cell lines co-cultured on the acellular dermal membrane were used to construct the 3D-OMM. After 4 days of culture, the discs were inserted into the holes prepared within the membrane of 3D-OMMs. The contour formed by the tissue was evaluated after 14 days of culture. Results: The UV treatment of abutment materials resulted in the formation of more non-pocket-tissue types among the PTx group (p = 0.002). Of all materials tested, soft tissue contour around YSZ showed higher scores for the non-pocket type in both non- and UV-treated groups. Conclusions: The non-pocket type of tissue attachment was frequently found in all surfaces modified by photofunctionalization, particularly zirconia. The 3D-OMM can be used to evaluate the biological endpoints of implant surface modifications

Current Advances of Three-Dimensional Bioprinting Application in Dentistry: A Scoping Review

Three-dimensional (3D) bioprinting technology has emerged as an ideal approach to address the challenges in regenerative dentistry by fabricating 3D tissue constructs with customized complex architecture. The dilemma with current dental treatments has led to the exploration of this technology in restoring and maintaining the function of teeth. This scoping review aims to explore 3D bioprinting technology together with the type of biomaterials and cells used for dental applications. Based on PRISMA-ScR guidelines, this systematic search was conducted by using the following databases: Ovid, PubMed, EBSCOhost and Web of Science. The inclusion criteria were (i) cell-laden 3D-bioprinted construct; (ii) intervention to regenerate dental tissue using bioink, which incorporates living cells or in combination with biomaterial; and (iii) 3D bioprinting for dental applications. A total of 31 studies were included in this review. The main 3D bioprinting technique was extrusion-based approach. Novel bioinks in use consist of different types of natural and synthetic polymers, decellularized extracellular matrix and spheroids with encapsulated mesenchymal stem cells, and have shown promising results for periodontal ligament, dentin, dental pulp and bone regeneration application. However, 3D bioprinting in dental applications, regrettably, is not yet close to being a clinical reality. Therefore, further research in fabricating ideal bioinks with implantation into larger animal models in the oral environment is very much needed for clinical translation