Surgical treatment of peri-implantitis with or without adjunctive graft material: a systematic review and meta-analysis of randomized controlled trials.

This systematic review and meta-analysis was performed to compare the clinical effect of surgical treatment of peri-implantitis alone or in combination with graft material. Literature searches were conducted up to June 20, 2020. Randomized controlled trials (RCTs) comparing the clinical effects of open flap debridement (OFD) alone and OFD with adjunctive graft materials for the treatment of peri-implantitis were included. Probing depth (PD) changes and marginal bone level (MBL) changes were assessed and expressed as the standardized mean difference (SMD) with 95% confidence interval (CI). Subgroup analyses and sensitivity analyses were conducted. The search yielded 7419 articles, five of which were analysed quantitatively. The adjunctive use of graft materials in OFD did not provide additional PD improvements (SMD 0.46, 95% CI -0.13 to 1.05; P = 0.13), but did yield additional MBL improvements (SMD 1.04, 95% CI 0.71-1.37; P < 0.01). The degradability of the material, number of implants included per patient, and risk of bias did not have significant effects on the results, but the origin of the material may affect the PD improvements. Based on the available evidence, the adjunctive use of graft materials in the surgical treatment of peri-implantitis can significantly improve MBL changes but not PD changes.

Classification and treatment strategies for condylar fractures in children.

In this study, we aimed to describe a classification method (position and displacement (PD) classification) and the corresponding treatment strategies for condylar fractures in children, based on the anatomical position and displacement of the fractures. Moreover, we aimed to explore the effect of the treatment strategies for condylar fractures in children. Such fractures were classified into the following three types by PD classification: condylar head fracture (type A), mildly displaced condylar neck and base fracture (type B), and severely displaced condylar neck and base fracture (type C). According to this classification, we proposed the corresponding treatment strategy of closed treatment for types A and B fractures and open treatment for type C fractures. Eighty-four patients who had 123 condylar fractures (type A = 97, type B = 16, type C = 10) were included in this study. Type A fractures showed the restoration of normal function with favourable remodelling in the condyles. Types B and C fractures had good function and symmetry in the condylar angle and height of the condylar neck. The PD classification and corresponding treatment strategies may serve as a better option for the clinical treatment of condylar fractures in children.

[Expert consensus on the treatment of oral and maxillofacial space infections].

Oral and maxillofacial space infections (OMSI) are common diseases of the facial region involving fascial spaces. Recently, OMSI shows trends of multi drug-resistance, severe symptoms, and increased mortality. OMSI treatment principles need to be updated to improve the cure rate. Based on the clinical experiences of Chinese experts and with the incorporation of international counterparts' expertise, the principles of preoperative checklist, interpretation of examination results, empirical medication principles, surgical treatment principles, postoperative drainage principles, prevention strategies of wisdom teeth pericoronitis-related OMSI, blood glucose management, physiotherapy principles, Ludwig's angina treatment and perioperative care were systematically summarized and an expert consensus on the diagnosis and treatment of OMSI was reached. The consensus aims to provide criteria for the diagnosis and treatment of OMSI in China so as to improve the level of OMSI treatment.

[Clinical retrospective study of navigation guided impacted maxillary supernumerary tooth extraction].

Objective: To analyze the efficiency and safety of navigation guided extraction of impacted supernumerary tooth. Methods: Twenty-five cases of navigation guided supernumerary tooth extraction and 25 cases of non-navigation guided supernumerary tooth extraction (control group) were included in the study. Each group had 3 cases with one impacted supernumerary tooth and 22 cases with two impacted teeth. Results: Preoperative navigation system designing time was (45.0±8.0) min in average. Navigation system installation time was (15.0±2.8) min. The average operation time was (0.64±0.08) hour in navigation group and (0.91±0.09) hour in control group. Conclusions: Navigation guided extraction of impacted supernumerary tooth takes less time for operation but more time for the preoperative navigation system design.

VEGF is up-regulated by hypoxic stimulation and related to tumour angiogenesis and severity of disease in oral squamous cell carcinoma: in vitro and in vivo studies.

The present study was aimed to speculate whether the up-regulation of VEGF in oral squamous cell carcinoma (OSCC) is associated with oxygen levels, tumor angiogenesis and severity of disease. Under different oxygen levels, VEGF protein production in two oral cancer cell lines was quantitatively documented by using ELISA kit. Correlations between expression of VEGF, microvessel density, and various clinico-pathologic factors were studied in forty patients with OSCC. VEGF production was continuously elevated in supernatants from both cell lines in respond to the drop of oxygen levels. When oxygen level decreased to 1%, there was a 2.1-fold and nearly a 2.9-fold elevation of VEGF production in TSCCa and GNM cell line, respectively. On hypoxia VEGF production also presented a time-dependent up-regulation in both oral cancer cell lines. VEGF positivity was correlated with regional lymph nodal involvement and clinical stage. Microvessel density was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. The presence of hypoxia in oral cancers is partly responsible for the up-regulation of VEGF. The elevation of VEGF expression in OSCC tissues correlates with the increased microvessel density and severity of the disease.

Potential role of disc repositioning in preventing postsurgical recurrence of traumatogenic temporomandibular joint ankylosis: a retrospective review of 17 consecutive cases.

The potential role of disc repositioning in preventing postsurgical recurrence of traumatogenic temporomandibular joint (TMJ) ankylosis was investigated. Seventeen cases of traumatogenic TMJ ankylosis underwent disc repositioning during arthroplasty. During surgery, the dislocated disc was carefully dissected outside the ankylotic TMJ and repositioned over the top of the condylar stump, and then sutured to the soft tissue of the zygomatic root. In the 22 ankylotic TMJs of the 17 patients, dislocated discs were found in front of the ankylotic TMJ, behind the ankylotic TMJ or between the ramus and fossa. At the last follow-up (longer than 1 year) examination, interincisal opening distances ranged from 24 to 43 mm (mean 32.86 mm). No recurrence and TMJ symptoms were found during the period of follow-up. Disc repositioning in the treatment of traumatogenic TMJ ankylosis proves to be a feasible and effective method of preventing recurrence of this condition.

Lumbar intervertebral disc prosthesis. An experimental study.

To provide a more effective treatment and improve the outcome of surgical treatment of lumbar intervertebral disc protrusion, the values of lumbar intervertebral disc prosthesis (LIDP) were investigated. LIDP was specially designed and made of silicone rubber. The properties of material mechanics were investigated by compressive test and damage test of LIDP specimens. The biocompatibilities of LIDP were observed experimentally in monkeys. The surgical applicabilities were studied by in vitro experiments of fresh human lumbar spine. The results showed that LIDP has the advantages of good biomechanical applicability, biocompatibility and surgical applicability. LIDP is able to maintain the intervertebral space, stress balance and stability of the lumbar spine. after lumbar intervertebral disc excision, the replacement of LIDP could restore the functions of the lumbar spine and improve the curative results of disc excision.

The PI3K/Akt signalling pathway may play an internal role related to abnormal condylar growth: a preliminary study.

Developmental deformity of the mandible is one of the most common craniofacial malformations and is closely related to abnormal condylar growth. In this study, the role of PI3K/Akt signalling in the regulation of chondrocyte proliferation and hypertrophic differentiation in the condylar cartilage was studied. Immunohistochemical staining was used to investigate the expression of PI3K and p-Akt in the rat condyle cartilage. Rat condylar chondrocytes were cultured for the investigation of chondrocyte proliferation and hypertrophic differentiation when PI3K/Akt was inhibited. In addition, organ culture of the rat mandibular condyle was performed to evaluate the condyle cartilage growth while PI3K/Akt was inhibited. PI3K-positive cells and p-Akt-positive cells showing cytoplasmic staining were found to be present in the condylar cartilage. Reduced cell proliferation was observed in the culture of rat condylar chondrocytes when PI3K/Akt was inhibited; however, the hypertrophic differentiation level was increased. The proliferative zone thickness of condylar cartilage in the experimental group was less than that in the control group (P=0.00185), but the hypertrophic zone was greater than that in the control group (P=0.01048). PI3K/Akt signalling exerts opposite influences on chondrocyte proliferation and hypertrophic differentiation of the condylar cartilage, and these data suggest that PI3K/Akt is a potential intracellular regulation signal pathway in condylar cartilage development.

Clinical characteristics and treatment of superolateral dislocation of the mandibular condyle.

The aim of this retrospective study was to investigate the clinical characteristics of superolateral dislocation of the mandibular condyle, and to review our experience of its treatment. Thirteen patients were included in this study. Demographic information and details of their original injury were analyzed by descriptive statistics and the treatment methods were summarized. These patients could be classified into three types: (1) unilateral dislocation with isolated condylar fracture (n=3); (2) unilateral dislocation with associated condylar fracture and other mandibular fracture (n=7); (3) bilateral dislocation with associated condylar fracture and other mandibular fracture (n=3). Treatment involved three main aspects: (1) relief of the condylar dislocation by manual manipulation or open reduction; (2) reduction of the medial condylar fragment and fixation with screws, or removal of the fragment if less than 50% of the condylar width; however, in one case with a tiny condylar fragment, this was left in situ; (3) management of the other associated mandibular fractures by open reduction and internal fixation (ORIF). Follow-up ranged from 6 to 20 months (average 13.69 months). Satisfactory functional outcomes were achieved in these cases. The results of this study indicate that superolateral dislocation of the condyle assumes many forms, and the treatment depends on the presence of fractures.

Temporalis muscle flap for immediate reconstruction of maxillary defects: review of 39 cases.

This study evaluated the advantages and complications associated with immediate reconstruction of maxillary defects after maxillectomy and the relationship between defect tissues classification and postoperative results after using the temporalis muscle flap. In this retrospective study, the records of 39 patients who underwent immediate reconstruction surgery using temparolis myofascial flap following maxillectomy from April 1989 to February 2009 were reviewed. Demographic data, features of the disease, follow-up, outcome and complications were analysed. Patients were classified into three groups, to ascertain the influence between defect classification and functional results, aesthetic outcomes and complications in each group. Of the 39 cases, all tissue flaps survived. 5 patients underwent postoperative radiotherapy, which did not seem to influence the outcome of the reconstructive procedure. There was one case of oroantral fistula, which could easily be obturated with the prosthesis. One patient developed haematoma in the donor site 5 days after surgery. Postoperative speech was good, facial appearance was normal and ocular function remained unchanged. Postoperative aesthetic and functional results were satisfying. The temporalis muscle flap can be considered as a first-line reconstructive option for maxillary defects. Acceptable functional and aesthetic outcomes can be expected in high rates.

The role of the disc in the healing of displaced subcondylar fracture in the growing period: an experimental study in rats.

The purpose of this study was to evaluate the role of the disc in the healing of condylar fractures in the growing period. 40 growing and adult male Wistar rats were randomized into 4 equal groups: growing rats suffering condylar fracture with disc damage; growing rats suffering condylar fracture without disc damage; adult rats suffering condylar fracture with disc damage; adult rats suffering condylar fracture without disc damage. 3 months after the operation all animals were killed and the outcomes were compared using mandible deviation measure, body weight evaluation and histological observation. In growing rats, when the disc was undamaged maintaining its relation to the condyle head, even though the condylar fractured fragment was displaced, the condyle healed and recovered almost to normality in 3 months. In the same condyle fracture form, once the disc was damaged and lost the normal relation with the condyle head, the outcome was unfavourable. The occurrence of damage to the disc and its attachment to the condyle head are important factors in the healing of condyle fractures in the growing period.