Influence of venous stasis on survival of epigastric flaps in rats

Venous congestion results in tissue damage and remains the most common reason for failure of transfer of microvascular free flaps if it is not recognised early. The purpose of this study was to measure the critical duration of venous congestion and the resultant survival of flaps according to the duration of venous stasis. A standard epigastric flap was raised and repositioned in 35 rats, seven of which acted as controls. The superficial inferior epigastric vein was fully occluded for four, five, six, or seven hours in the rest (n = 7 each group). Subsequently, the rats were monitored for one week, and the resultant necrotic areas were photographed. After five, six, and seven hours of venous stasis, the incidence and area of necrosis were significantly increased (p = 0.04 in each) above that of the control. The degree of necrosis after seven hours of venous stasis was significantly greater than that after four or five hours (p = 0.01 and 0.02, respectively). The duration of venous congestion is therefore a potential risk for the survival of free flaps, as it results in operative complications and may jeopardise the whole procedure. After a critical period of venous stasis we reach a point of no return, and any attempt to salvage the compromised flap will be in vain. Based on these results, we think that monitoring by an experienced surgeon at intervals of no longer than three hours is essential for the successful salvage of venous congestion in microvascular free flaps.     

Reconstruction of intraoral defects after resection of cancer with two types of submental artery perforator flaps

The submental island flap is a common choice for reconstruction of intraoral defects. To obtain a thinner, more pliable flap and get a better oncological result, the submental artery perforator flap has been proposed, and to assess its feasibility for closure of defects after resection of cancers of the oral cavity we studied 20 patients, each of whom was treated in this way. All the flaps were classified into those with septocutaneous perforators (n = 16) and those with musculocutaneous perforators (n = 4), and the main veins that drained the flaps were two submental veins (n = 17). There were two patterns of venous drainage: in pattern 1 (n = 9) the external jugular vein provided the primary venous drainage, and in pattern 2, the submental veins drained mainly into the facial vein, the common facial vein, and the internal jugular (n = 10). In one patient the submental veins bypassed the facial vein to drain into the internal jugular. Eighteen of the 20 patients had no postoperative complications. The remaining two developed mild venous congestion of the flaps, which was resolved with conservative management and no skin loss. No local or regional recurrence was detected after a mean (range) follow-up of 21 (4-35) months. This is a simple, reliable flap that can be used for the reconstruction of intraoral defects after resections for cancer, but its oncological outcome still requires proof in long-term, large-scale, clinical trials.     

Complications and loss of free flaps after reconstructions for oral cancer

The aim of this retrospective study was to analyse the incidence of complications and loss of flaps after primary reconstructions for oral cancer in 191 patients at our hospital over the five years 2005–2010. The patients’ clinical and personal details, characteristics of the tumours, types of microvascular flap, complications, and outcomes were recorded. The soft tissue flaps used most often were the fasciocutaneous radial forearm free flap (RFFF) (n = 86, 45%) and the anterolateral thigh free flap (ALTFF) (n = 48, 25%) while the most commonly used osseous flap was the deep circumflex iliac artery flap (DCIA) (n = 25, 13%). There were postoperative complications that required intervention in a quarter of the patients, most often in the age group 41–50 years (p = 0.018). Older age was not associated with the development of complications. The overall survival of all free flaps was 181/191 (95%), and the only significant individual predictor of loss of a flap was reconstruction with a DCIA (p = 0.016), five of the 25 of which were lost. We conclude therefore that DCIA free flaps are associated with an increased risk of failure; the method of osseous reconstruction for maxillofacial reconstruction should be selected carefully; and carefully chosen older patients do not seem to be at increased risk of morbidity.     

Complications and outcome after free flap surgery for cancer of the head and neck

We retrospectively studied 136 patients who had free flap reconstruction for cancer of the head and neck at a single centre (2008–2015) to evaluate complications, assess factors associated with them, and analyse their impact on outcome. Preoperative and perioperative data, and surgical and medical complications were recorded, and the impact of the complications on duration of hospital stay and survival were assessed. A total of 86 (63%) patients had complications. Compared with those who did not, they had a higher rate of alcohol abuse (21/86, compared with 5/50, p = 0.039), longer operations (median (IQR) 565 (458–653 compared with 479 (418–556) minutes, p < 0.001), and greater intraoperative loss of blood (725 (400–1150) compared with 525 (300–800) ml, p = 0.042). Complications were more common in patients who had fibular flaps and T4 disease (22/86 compared with 4/50, p = 0.010; 47/80 compared with 16/47, p = 0.015, respectively). Those who had complications also stayed in hospital longer (median (IQR) 9 (7–12) compared with 15 (10–21) days, p < 0.001). Cumulative mortality was higher in patients with late complications (those that occurred after the fourth postoperative day) (61% compared with 36%, p = 0.004). In conclusion, complications in more than half the patients were related to alcohol abuse, a more complicated intraoperative course, and fibular flaps. Complications were associated with a longer hospital stay, and survival was higher in those who did not have late complications than in those who did.     

Effectiveness of irrigation with chlorhexidine after removal of mandibular third molars: a randomised controlled trial

To evaluate the effect of postoperative irrigation with chlorhexidine on inflammatory complications after the extraction of lower third molars under local anaesthesia, we recruited 100 patients to participate in a controlled, single-blind, randomised clinical trial. They were assigned to one of two groups: the intervention group (postoperative irrigation of the surgical site with chlorhexidine for seven days) or the control group (postoperative chlorhexidine mouth rinse for seven days). The primary outcome variables were pain, swelling, trismus, infection, and alveolar osteitis. The secondary outcome variables were wound dehiscence and food impaction. A total of 95 participants completed the study (47 in the irrigation group and 48 in the rinse group). In the irrigation group, alveolar osteitis and facial swelling had reduced significantly at seven days postoperatively (both p < 0.01). Pain scores had also reduced significantly at seven days (p < 0.01), but not at 48 hours, and patients had lower levels of food impaction (p < 0.01) and less severe symptoms (p = 0.02). Routine irrigation with chlorhexidine after the extraction of third molars helps to reduce pain and lowers the incidence of alveolar osteitis.     

Morphological study of the changes after sagittal split ramus osteotomy in patients with facial asymmetry: measurements of 3-dimensional modelling

The effects of bilateral sagittal split ramus osteotomy (BSSRO) on the temporomandibular joint (TMJ) are still not well understood. The aim of this study was to compare the morphological differences among unaffected subjects on the one hand, and patients with facial asymmetry before and after BSSRO on the other. Ten Chinese patients (preoperative and postoperative groups, mean (SD) age 25 (5) years) diagnosed with facial asymmetry and 10 unaffected subjects (control group, mean (SD) age 27 (5) years) were recruited prospectively. The 3-dimensional morphological measurements made on 3-dimensional models in each group were assessed by analysis-of-variance (ANOVA) and Student’s t test, and probabilities of <0.05 were accepted as significant. The horizontal condylar angle (HCA), coronal condylar angle (CCA), sagittal ramus angle (SRA), medial joint space (MJS), lateral joint space (LJS), and superior joint space (SJS) differed significantly between the preoperative and control groups (HCA: p = 0.000, CCA: p = 0.000, SRA(left/undeviated side): p = 0.002, MJS(left/undeviated side): p = 0.000, MJS(right/deviated side): p = 0.007, LJS(right/deviated side): p = 0.000, SJS(left/undeviated side): p = 0.000, SJS(right/deviated side): p = 0.000). The SRA, MJS, LJS, and SJS differed significantly between the preoperative and postoperative groups (SRA(left/undeviated side): p = 0.012, MJS(left/undeviated side): p = 0.002, LJS(right/deviated side): p = 0.021, SJS(left/undeviated side): p = 0.000, SJS(right/deviated side): p = 0.001), And the SRA, MJS, and LJS in the preoperative group differed significantly between the deviated and undeviated side (SRA: p = 0.006; MJS: p = 0.003; LJS: p = 0.011). However, there were no significant differences in the postoperative and control groups between the deviated and undeviated sides. BSSRO improved the asymmetrical morphology of the TMJ and alleviated the symptoms.     

One versus two venous anastomoses in microsurgical head and neck reconstruction: a cumulative meta-analysis

Venous compromise is still the most common cause of free flap failure. The use of two venous anastomoses has been advocated to reduce venous compromise. However, the effectiveness of this approach remains controversial. A systematic review and cumulative meta-analysis was performed to assess the effect of one versus two venous anastomoses on venous compromise and free flap failure in head and neck microsurgical reconstruction. A total of 27 articles reporting 7389 flaps were included in this study. On comparison of one versus two venous anastomoses, the odds ratio (OR) for flap failure was 1.66 (95% confidence interval 1.11–2.50; P = 0.014) and for venous compromise was 1.50 (95% confidence interval 1.10–2.05; P = 0.011), suggesting a significant increase in the flap failure rate and venous compromise rate in the single venous anastomosis group. These results show that the execution of two venous anastomoses has significant effects on reducing the vascular compromise and free flap failure rate in head and neck reconstruction.     

Evaluation of biochemical variables in patients with trigeminal neuralgia

The aim of this study was to evaluate the calcium, sodium, potassium, serum iron, vitamin B12, and albumin concentrations, and alkaline phosphatase (ALP) activity, in samples of serum from patients with primary trigeminal neuralgia (TN), and investigate the associations between them. Results from 73 patients who had been diagnosed with primary TN between December 2015 and 2017 were compared with those of 70 healthy subjects. Calcium (p = 0.013), iron (p = 0.004), and albumin (p = 0.001) concentrations in the primary TN group were significantly lower than those in the control group, whereas the ALP activity was significantly higher in the TN group than in the control group (p = 0.007). However, there was no significant difference in the sodium, potassium, or vitamin B12 concentrations. Biochemical variables have a role in the pathogenesis and treatment of primary TN, but there are few studies that characterise the relations between the condition and the biochemical changes. Further studies are therefore necessary to gain more information.     

Role of a two-step suture in the prevention of postoperative transoral salivary fistulas during reconstruction of the oral cavity

Transoral salivary fistulas are one of the most serious postoperative complications after operations for oral cancer, and we propose a new, two-step suture method to avoid them. From January 2005 to September 2017, 240 patients were recruited at the Shanghai Ninth People’s Hospital and divided into experimental (n = 89) or control (n = 151) groups. The experimental group was treated by a two-step suture technique, while the control group had conventional sutures. Statistical differences were assessed using the chi squared and t tests, as appropriate. Only two patients developed transoral salivary fistulas in the experimental group, while in the control group there were 14 (9%). The incidence of fistulas in the experimental group was significantly lower than that in the control group (p = 0.035). Regression analysis showed that there was a significant correlation between the groups and the incidence of salivary fistulas (p = 0.032). The two-step suture technique is safe, effective, and easy to learn, and could reduce the incidence of postoperative salivary fistulas.     

Preoperative assessment of the risk of postoperative death in patients with oral squamous cell carcinoma: a consideration beyond age,sex, and stage of cancer

Despite improvements in the management of patients in critical care, about 3% patients who have an operation with curative intent for oral squamous cell carcinoma (SCC) do not survive their stay in hospital. Our aim was to assess the risk factors for postoperative death that were independent of the stage of the cancer, or the age and sex of the patients. We screened 4760 consecutive inpatients at a maxillofacial tertiary care centre from 2011 to 2016, and 34 of them had died within the first three months after operation. We matched them with a further 34 patients with the same TNM stage, age, and sex. General personal and clinical data and preoperative laboratory values were screened, and we applied a Charlson Comorbidity Score (for anaesthetic risk) for each group. Patients’ mean (SD) age was 66 (12) years old. There was no significant difference in sex (p = 1), age (p = 0.718), or TNM classification. Those who died after operation had significantly more renal (p = 0.027) and gastrointestinal (p = 0.006) diseases, but cardiac diseases (p = 0.468) and diabetes mellitus (p = 1) were not significant risk factors in themselves. Patients who died postoperatively had significantly worse risk scores (p = 0.001) overall. The most common causes of death were septic shock (n = 10) and acute cardiac (n = 9) or respiratory failure (n = 7). Our findings suggested that general diseases were not intrinsically a contraindication for operation with curative intent. The Charlson Comorbidity Score helped to detect potentially fatal courses and could be useful in the preoperative assessment of patients whose general health is not good.     

Use of a microvascular coupler device for end-to-side venous anastomosis in oral and maxillofacial reconstruction

The aim of this study was to compare the use of a microvascular coupler device (MCD) for end-to-side venous anastomosis (ETS group) and phleboplasties combined with MCD for end-to-end venous anastomosis (ETE group) in free tissue transfer for oral and maxillofacial reconstruction, with regard to the anastomosis time and occurrence of postoperative vascular crisis. The ETS group included 22 patients and the ETE group included 40 patients. Patient demographic data, anastomotic time, coupler size, microvascular complications, and flap survival rates were collected and analyzed. In the ETS group, the most suitable donor vessel size was greater than 2 mm, varying from 2 mm to 4 mm. The average anastomosis time was 3.35 ± 0.89 min in the ETS group and 7.80 ± 2.93 min in the ETE group; the difference between the groups was statistically significant (p < 0.0001). There were no statistically significant differences in complications or outcomes between the two groups. The ETS venous anastomosis with MCD technique is a better choice for anastomosis when the donor vessel size is greater than 2 mm. In those cases with mismatched veins, ETS venous anastomosis with MCD could significantly reduce the anastomosis time compared to ETE venous anastomosis with MCD after phleboplasties.     

Botulinum toxin A for patients with orofacial dystonia: prospective,observational, single-centre study

The objective of this study was to demonstrate the efficacy of intramuscular botulinum toxin type A (BTX-A) as a method of controlling the symptoms of focal facial dystonia. A prospective, longitudinal, observational, pre–post (case-series) single-centre study was conducted over a period of 3 months, involving 30 patients with focal dystonia. The patients were enrolled on a first-come, first-served basis. For all patients, the abnormal movements were evaluated using the Abnormal Involuntary Movement Scale (AIMS). The AIMS results were recorded immediately before BTX-A injection (primary predictor variable) and after 3 months (the toxin reaches its maximum effect 2 weeks after injection, and the effect is maintained for 3 months). An improvement in AIMS score was the primary outcome variable. Treatment efficacy was evaluated using the Pearson correlation index with a level of significance of P < 0.05. The average age of the study subjects was 70.9 ± 12.7 years (20 female, 10 male). The mean dose of BTX-A used was 27.4 ± 20.5 U. The mean improvement in AIMS score after treatment was 5.2 ± 4.2. A significant correlation was found between the dose applied and the reduction in AIMS score (P < 0.05). BTX-A can be used in the treatment of focal dystonia and provides reproducible results.     

Inhibition of secondary caries in vitro by addition of chlorhexidine to adhesive components

Objective

To investigate secondary caries inhibition after dentine pre-treatment with 2% CHX, experimental addition of CHX in primer and adhesive of a 3-step adhesive system, and industrial addition od CHX in a 2-step adhesive system.

Otitis media with effusion in Nigerian children with cleft palate: incidence and risk factors

Otitis media with effusion is common in children with cleft palate, and the aim of this study was to find out its incidence and risk factors in Nigerians. We prospectively studied 84 patients (42 with cleft palate and 42 control subjects); 27 were male and 15 female, who were age and sex matched with control subjects. The extent and size of the clefts were measured using a dental cast and Vernier calipers, and the otitis media was diagnosed with otoscopy and tympanometry. The mean (SD) age of the groups was 11 (7) months (range 1–33). Twelve children in the cleft group had otitis media compared with three in the control group. Infants and boys were more likely to be affected. There was a significant association between age (p = 0.02), sex (p = 0.01), and size of cleft (p = 0.00). However, only the size of the cleft was confirmed to be an independent predictor, with children who had extremely wide clefts being more likely to develop otitis media than those with narrow clefts (OR = 8.71, 95%CI = 1.07 to 70.5).We conclude that the incidence of otitis media with effusion was higher among children with cleft palate than among those who did not have a cleft. Infants had a higher incidence than older children, and boys had a higher incidence than girls. Age, sex, and the size of the palatal cleft were significantly associated with otitis media, but not the extent of clefting.     

Evaluation of surface treatments of monolithic zirconia in different sintering stages

Purpose

This study evaluated the effect of surface treatment of zirconia in pre-sintered and post-sintered stages on its surface roughness, phase transformation, and biaxial flexural strength (BFS).

Implant stability using piezoelectric bone surgery compared with conventional drilling: a systematic review and meta-analysis

The aim of this systematic review was to assess the primary and secondary stability of dental implants placed at sites prepared with piezoelectric bone surgery (PBS) and conventional drilling (CD). The PubMed/MEDLINE and Cochrane Library databases were searched without date or language restriction up to June 2017. Controlled clinical trials in which each patient received implants placed at sites prepared with both PBS and CD were selected. Implant stability had to be measured on day 0 and during the osseointegration period. Methodological quality was assessed using the Cochrane Collaboration tool. A meta-analysis was performed to compare primary stability (on day 0) and secondary stability (after 2 and 3 months) between the two groups. The studies included were determined to have a high risk of bias. There was no significant difference between the two groups for primary stability (on day 0) (P = 0.51). After 2 and 3 months, secondary stability was statistically higher in implants placed with PBS preparation (P = 0.04 and P = 0.01, respectively). The implant survival rate was 97.5% in the CD group and 100% in the PBS group. PBS preparation improves secondary stability after 2 and 3 months in comparison to CD, with similar implant survival rates. Further studies are needed to determine whether implant osseointegration periods could be shortened with PBS preparation.     

Retroseptal transconjunctival approach for fractures of the zygomaticomaxillary complex: a retrospective study

We designed a retrospective study to evaluate the efficacy of retroseptal transconjunctival approaches in the management of fractures of the zygomaticomaxillary complex (ZMC). The patients were from a single institution, and had had three-point fixation of fractures of the ZMC between 2008 and 2016. A total of 77 patients (56 men and 21 women with a mean (range) age of 28 (18–54) years), were divided into two groups. Group I (n = 51) had had reduction and fixation of the infraorbital rim using a retroseptal transconjunctival approach. In group II (n = 26) the same approach had been used with lateral canthotomy and inferior canthlolysis for both the infraorbital rim and the zygomaticofrontal region. We analysed the association of both approaches with the outcomes of reduction, fixation, and complications. Suboptimal results were found in 13 patients in group I and one in group II (p = 0.017). There were also three patients with trichiasis and two with entropion in group I, and one each of both complications in group II. There was only one patient with a malopposed lateral canthus in group II. All 26 patients in group II had no perceptible scar along the extended line of incision. The risk of a suboptimal outcome was reduced by 20% (relative risk = 0.8) in group II. The retroseptal transconjunctival approach with lateral canthotomy and inferior cantholysis is safe, aesthetic, and effective in the management of fractures of the ZMC.     

Changes in position of the hyoid bone and volume of the pharyngeal airway after mandibular setback: three-dimensional analysis

Important aspects of orthognathic surgery are the effects of skeletal movement and changes in the position of the hyoid bone, tongue, soft palate, and dimensions of the pharyngeal airway. Our aims were to evaluate the 3-dimensional changes in the pharyngeal airway and in the position of the hyoid bone after mandibular setback in 30 patients who were diagnosed with mandibular prognathism and were treated by intraoral vertical ramus osteotomy (IVRO). Three-dimensional cone-beam computed tomographic (CT) images were obtained preoperatively, one month postoperatively, and one year postoperatively. The total pharyngeal volume decreased between the preoperative state and one month and one year afterwards. The hyoid bone had moved 2.0 mm posteriorly and 3.15 mm superiorly by one month postoperatively. The position of the hyoid bone was affected by changes in posterior and superior movement of the B point at one month (r = 0.44, p = 0.015 and R = 0.63, p = 0.000, respectively) and also by superior movement of the B point at one year (r = 0.57, p = ?0.001). There was an advantageous relation between posterior positional changes in the B point (mandibular setback), and volumetric changes in the hypopharyngeal and total pharyngeal airway, so maxillofacial surgeons should consider the reduction in airway when planning excessive mandibular setback.     

Restoration integrity,but not material or cementation strategy determined secondary caries lesions next to indirect restorations in vitro

Objective

Secondary caries lesions next to direct restorations are associated with the restoration material and the integrity of the tooth-restoration-interface (presence of interfacial gaps) as well as the application of masticatory forces. It remains unclear if this is true for indirect restorations. We aimed to evaluate secondary lesions next to conventionally-cemented partial gold (PG) and adhesively-cemented partial ceramic (PC) restorations, placed with or without interfacial gaps.

Superficial versus deep system single venous anastomosis in the radial forearm free flap: a meta-analysis

The selection of the superficial or deep drainage system for use with the radial forearm free flap (RFFF) remains controversial. The aim of this study was to identify the optimal drainage system for single venous anastomosis. A systematic review and cumulative meta-analysis was performed to assess superficial and deep system single venous anastomosis for use with the RFFF in postoperative reconstruction of the head and neck. This study included 1073 flaps (495 superficial system-based flaps, 578 deep system-based flaps) reported in six studies. The outcomes assessed in the studies selected for this meta-analysis included venous compromise, flap failure, and the salvage success rate. Venous compromise was more common in the superficial system group (odds ratio (OR) 2.29, 95% confidence interval (CI) 1.36–3.86, P = 0.002). The rate of successful salvage was higher with the superficial system (OR 8.19, 95% CI 1.75–38.3, P = 0.008). The rate of flap failure was lower in the superficial system group (OR 0.30, 95% CI 0.04–2.48, P = 0.27). Although the deep system showed a lower risk of venous compromise, the evidence provided by the meta-analysis was insufficient to determine which type of drainage system is more suitable for single venous anastomosis in RFFF. All included studies were cohort studies; therefore, findings must be interpreted with caution.