Clinical, volumetric and densitometric evaluation of tissue engineered constructs for secondary alveolar cleft reconstruction: A randomized clinical trial

The Therapeutic Use of Dental Mesenchymal Stem Cells in Human Clinical Trials

Mesenchymal stem cells (MSCs), characterized by their undifferentiated and multipotent nature, can be derived from various sources, including bone marrow, adipose, and dental tissues. Among these, dental MSCs (DSCs) exhibit universal MSC characteristics and are attracting considerable attention for regenerating oral and craniofacial tissues. This review provides a contemporary overview of recently published clinical studies using DSCs for various orodental and maxillofacial regenerative applications, including bone, periodontal, and endodontic regeneration. It also explores the utilization of DSCs in treating systemic conditions, exemplified by their application in managing conditions such as COVID-19 and osteoarthritis. The available evidence underscores the potential of DSCs and their secretome as efficacious tools in regenerative medicine for both dental and nondental clinical applications, supporting the continued promise of stem cell-based therapies. It is nevertheless evident that there are a number of important challenges that restrict the widespread utilization of DSCs, namely, difficulty in standardizing autologous preparations, insufficient cell surface marker characterization, high production costs, and regulatory compliance requirements. Further, the unique requirements of dental applications, especially complex structures such as the periodontium, where temporospatial control over the healing process is required, necessitate the combination of stem cells with appropriate scaffolds according to the principles of tissue engineering. There is currently insufficient evidence to support the clinical translation of DSCs into clinical practice, and phase 3 clinical trials with standardized protocols for cell sourcing, propagation, dosing, and delivery are required to move the field forward. In summary, this review provides a contemporary overview of the evolving landscape of stem cell therapy, offering insights into the latest developments and trends as well as the challenges that need to be addressed for the widespread application of DSC-based cell therapies.

Stem Cells in Bone Tissue Engineering: Progress, Promises and Challenges

Bone defects from accidents, congenital conditions, and age-related diseases significantly impact quality of life. Recent advancements in bone tissue engineering (TE) involve biomaterial scaffolds, patient-derived cells, and bioactive agents, enabling functional bone regeneration. Stem cells, obtained from numerous sources including umbilical cord blood, adipose tissue, bone marrow, and dental pulp, hold immense potential in bone TE. Induced pluripotent stem cells and genetically modified stem cells can also be used. Proper manipulation of physical, chemical, and biological stimulation is crucial for their proliferation, maintenance, and differentiation. Stem cells contribute to osteogenesis, osteoinduction, angiogenesis, and mineralization, essential for bone regeneration. This review provides an overview of the latest developments in stem cell-based TE for repairing and regenerating defective bones.

Comprehensive repair of the alveolar cleft using cortical and cancellous bone layers: A retrospective study

To retrospectively review the clinical effect of comprehensive treatment of alveolar cleft (CTAC) using the mandible as the bone source. Patients with alveolar clefts who met the inclusion criteria were subjected to a CTAC protocol that included the following: (1) preoperative orthodontic treatment for creating good soft-tissue conditions; (2) 'area-like grafting' with subperiosteal osteogenic chin bone instead of cartilaginous osteogenic iliac bone; (3) simulation of normal bone anatomy via a sandwich-like bone graft consisting of 'cortical bone + cancellous bone + cortical bone'; and (4) strong internal fixation to ensure initial bone block stability. At 6 months postoperatively, the titanium plate was removed and cone-beam computed tomography was performed to evaluate the surgical results. A total of 54 patients underwent treatment with the CTAC protocol. The average age at the initial operation was 10.3 ± 2.1 years, and the average hospital stay was 2.8 ± 0.6 days. At 6 months postoperatively, 49 patients (90.7%) showed good clinical results. The transplanted bone block formed a 'cortical bone + cancellous bone + cortical bone' structure similar to that of the normal jawbone. A mature bone bridge formed, and the impacted permanent teeth continued to erupt and enter the bone graft area. CTAC is a comprehensive restorative solution for alveolar cleft repair that integrates multiple concepts, including orthodontics, embryology, anatomy, and improvements to surgical methods. The method is easy to perform, causes little surgical trauma, and shows a stable success rate, and is thus worth promoting.

A novel technique predicting velopharyngeal insufficiency risk in newborns following primary cleft repair. A randomized clinical trial comparing buccinator flap and Bardach two-flap palatoplasty

The study aimed to assess the efficacy of buccinator myomucosal flap (BMF) compared to Bardach two-flap use in primary cleft palatoplasty on palatal length and fistulation rate. Palatal length in relation to the pharynx is a critical factor regarding velopharyngeal function. The goal was to predict the risk of velopharyngeal insufficiency by comparing the potential of two different techniques in lengthening the palate and to decrease the fistulation rate. A total of 46 patients with complete wide cleft palate were randomly divided into two equal groups: a study group, in which the cleft palate defect was repaired by BMF; and a control group, in which patients' clefts were repaired by Bardach (two-flap) palatoplasty during primary repair. All patients were evaluated at 1-, 3- and 6-month intervals to detect the fistulation rate and to measure the palatal length by taking impressions, pouring casts to measure the palatal length from anterior reference point (incisive foramen) to the posterior reference point(uvula) and calculating the change of palatal length. There was a significant increase in the palatal length measurements in the study (BMF) group (immediate postoperatively and at 3 and 6 months) compared to the control group (p < 0.001). Regarding the fistulation rate, there was no statistically significant difference (p = 0.346). The use of the buccinator flap during primary repair of cleft palate decreased the fistulation rate.

Alveolar cleft reconstruction utilizing a particulate autogenous tooth graft and a novel split-thickness papilla curtain flap - A retrospective study

During secondary alveolar cleft grafting, the use of autogenous cancellous bone harvested from the iliac crest is still considered the gold standard. Due to the risk of donor-site morbidity and excessive graft resorption, alternative grafting materials (e.g. intraoral bone, xenografts) have been tested. Autogenous tooth bone graft (ATB) is a novel material derived from extracted teeth. ATB has successfully been used in pre-prosthetic and periodontal surgery for hard-tissue reconstruction. Seven patients with unilateral cleft lip and palate were treated with ATB, using their own deciduous teeth for grafting. Defects were accessed utilizing a novel split-thickness papilla curtain flap. Cone-beam computed tomography scans were taken prior to and 3 months following cleft surgery to assess graft integration, graft stability, and the volume of the newly formed hard tissues. Hard-tissue gain, as measured at the 3-month follow-up, averaged 0.65 cm3 ± 0.26 cm3. Results showed acceptable graft integration and stability at the 3-month follow-up, with no adverse effects or excessive resorption of the graft. The use of ATB might be a feasible alternative for alveolar cleft grafting. However, long-term studies using a large sample size are required to derive further conclusions.

Comparison of two preserved cartilage iliac crest cortical-cancellous bone blocks graft harvesting techniques in children: A prospective, double-blind, randomized clinical trial

PURPOSE

To compare donor-site morbidity for alveolar bone grafting results following cartilage-preserving outer and inner cortico-cancellous iliac crest (OCIC and ICIC) bone block grafting in children.

MATERIALS AND METHODS

Patients were randomly divided into two groups and prospectively reviewed. In the OCIC and ICIC groups, cortico-cancellous bone blocks were harvested at outer and inner iliac crest respectively. Patient characteristics and surgical parameters were compared; pain intensity and duration, lateral femoral cutaneous nerve (LFCN) injury, gait disturbance, scar and contour satisfaction were analysed postoperatively.

RESULTS

Forty-nine consecutive patients (OCIC, 24; ICIC, 25) were included. There were no significant differences in patient characteristics or donor-site surgical parameters. The mean pain score on the first post-operative day was significantly lower in the OCIC group (3.75±1.70) than in the ICIC group (5.20±2.08) (p=0.012). The pain duration was similar in the two groups (median: 5 days). Temporary LFCN injury only occurred in 3 patients in the ICIC group. Postoperatively, the duck and circle gaits were observed in the OCIC and ICIC groups, respectively. There were no significant differences in the claudication duration, scar and contour satisfaction between the groups.

CONCLUSION

OCIC bone graft harvesting is marginally advantageous in children due to less early postoperative donor-site pain and a lower risk of nerve damage.