Hypoesthesia associated with mandibular movement after sagittal split ramus osteotomy

Purpose

This retrospective study investigated the relationship between the degree of neurosensory disturbance (NSD) and mandibular movement distance after sagittal split ramus osteotomy (SSRO) and assessed sensory recovery.

Methods

Lower lip hypoesthesia was evaluated at 1 week, 1 month, and 2 months after SSRO in 38 patients categorized according to the distance of mandibular movement: S group (0–7 mm; n = 17, 4 males and 13 females) and L group (7–14 mm; n = 21, 7 males, 14 females). Symptoms were evaluated by visual analog scale (VAS), tactile-threshold (SW) test, static 2-point discrimination (s-2PD) test, and current perception threshold (CPT) test.

Results

The two groups did not differ significantly in gender and age. The Aβ fiber results of the CPT test differed significantly between the groups at 1 week and 1 month postsurgery (P < 0.05). There were no significant differences between the groups throughout the period in terms of VAS, SW, s-2PD, Aδ fiber, and C fiber of CPT.

Conclusions

Post-SSRO, the incidence of NSD in terms of tactile sensation may be greater in the L group early postoperatively. This may assist surgeons in explaining postoperative hypoesthesia to patients preoperatively.

     

Increased local recurrence in advanced parotid malignancy treated with mastoidectomy without lateral temporal bone resection

Objective

We analyzed patients with advanced parotid malignancy requiring proximal facial nerve exposure undergoing mastoidectomy versus lateral temporal bone resection to determine differences in local and distant recurrence.

Study design

The study design is a case series with chart review.

Setting

The setting is in Tertiary care practice in Fort Worth, Texas from January1998 to January 2014.

Subjects and methods

The study included 120 patients with advanced parotid malignancy, 82 males between 19 and 87 years, and 38 females between 26 and 83 years. Patients with no overt bone involvement were treated with parotidectomy and mastoidectomy for exposure of the proximal facial nerve, and patients with clinically suspected (radiographic imaging or clinical fixation) bone involvement were treated with parotidectomy and lateral temporal bone resection. Follow up ranged from a minimum of 18 months to 11 years following surgery.

Results

Sixty patients were treated with mastoidectomy and 60 were treated with lateral temporal bone resection. In patients treated with mastoidectomy, 13 had local recurrence and 7 had distal recurrence. In patients treated with lateral temporal bone resection, 2 had local recurrence while 9 had distant recurrence. Statistical analysis revealed that patients treated with mastoidectomy developed local recurrence (p = 0.0022) more commonly than those treated with lateral temporal bone resection. There was no significant difference in distant recurrence between both groups (p = 0.5949).

Conclusions

Patients with advanced parotid malignancy should be treated aggressively with parotidectomy and lateral temporal bone resection regardless of bone involvement due to increased risk of local recurrence in those treated with mastoidectomy alone.

Level of evidence

Level of evidence is a 4 case series.

     

Utility of intraoperative nerve monitoring in thyroid surgery: 20-year experience with 1418 cases

Purpose

The efficacy of intraoperative nerve monitoring is controversial in the literature. This study of a single surgeon’s experience seeks to determine if the use of intraoperative nerve monitoring influences recurrent laryngeal nerve injury during thyroid surgery.

Methods

Six hundred fifty-seven patients with normal pre-operative vocal fold function underwent thyroid surgery without the use of intraoperative nerve monitoring from September 1997 to January 2007, while 761 patients underwent thyroid surgery from February 2007 to February 2016 with routine use of nerve monitoring. Patients were followed for a minimum of 6 months after surgery, and postoperative nerve function was determined by fiberoptic laryngoscopy. A Fisher test was used to determine if nerve injury was statistically different between both groups.

Results

In patients operated on without nerve monitoring, 21 patients were found to have postoperative vocal fold paralysis with nine regaining functioning. In patients operated on with nerve monitoring, 27 were found to have vocal fold dysfunction with 17 regaining function. Fisher test analysis, both with and without patients regaining function, showed no difference in nerve injury between groups (p > 0.05, p > 0.05).

Conclusion

Intraoperative monitoring during thyroidectomy may not prevent injury to the recurrent laryngeal nerve.

     

Effect of intervention using a messaging app on compliance and duration of treatment in orthodontic patients

Objectives

This study aims to determine the effectiveness of a messaging app (WeChat) in improving patients’ compliance and reducing the duration of orthodontic treatment (DOT).

Materials and methods

A randomized controlled trial was performed in a dental hospital and a clinic from August 2012 to May 2015. Orthodontic patients were included at the beginning of treatment. Patients with multiphase treatment or braceless technique were excluded. Participants were randomized to WeChat group (received regular reminders and educational messages) or control group (received conventional management) and were followed up until the treatment was completed. Primary outcome measure was DOT. Others were late and failed attendance, bracket bond failure, and oral hygiene condition.

Results

One hundred twelve patients in each group participated and completed the trial. DOT in WeChat group were 7.3 weeks shorter (P = 0.007). There were less failed attendance (3.1 vs. 10.9 %, P < 0.001), late attendance (20.1 vs. 29.9 %, P < 0.001), and bracket bond failure (11.8 vs. 16.1 %, P < 0.001) in WeChat group than control. There was no difference in orthodontic plaque index nor modified gingivitis index between the two groups before and after treatment. Number of failed attendances was identified as an independent factor affecting DOT (P = 0.004; HR = 0.89, 95 % CI 0.84 to 0.95).

Conclusions

The intervention with WeChat is effective in reducing the treatment duration and bracket bond failure, and improving the attendance in orthodontic patients.

Clinical relevance

DOT can be reduced by improving patient’s compliance. The messaging app is useful for outpatient education and management.

     

Prevalence of periodontitis in individuals with human leukocyte antigens (HLA) A9, B15, A2, and B5

Objective

Human leukocyte antigens (HLA) have been associated with periodontitis. Previous studies revealed HLA-A9 and HLA-B15 as potential susceptibility factors, while HLA-A2 and HLA-B5 might have protective effects. The aim of the study was to verify these associations in a group of HLA-typed blood donors with previously unknown periodontal status.

Materials and methods

In four German centers, 140 blood donors with known HLA class I status were enrolled and allocated to the following five groups: HLA-A9 (N = 24), HLA-B15 (N = 20), HLA-A2 (N = 30), HLA-B5 (N = 26), and controls (N = 40). Periodontal examination included the measurement of probing depths (PDs), clinical attachment level (CAL), bleeding on probing (BOP), and community periodontal index of treatment needs (CPITN).

Results

Carriers with HLA-A9 and HLA-B15 had higher values of mean PD (P < 0.0001), CAL (P < 0.0001), and BOP (P < 0.002) as well as sites with PD and CAL with ≥4 and ≥6 mm (P < 0.0003), respectively, than controls. Multiple regression analyses revealed HLA-A9, HLA-B15, and smoking as risk indicators for moderate to severe (CPITN 3–4; odds ratio (OR): 66.7, 15.3, and 5.1) and severe (CPITN 4; OR: 6.6, 7.4, and 3.8) periodontitis. HLA-A2 and HLA-B5 did not show any relevant associations.

Conclusion

The present data support a role of HLA-A9 and HLA-B15 as susceptibility factors for periodontitis, whereas HLA-A2 and HLA-B5 could not be confirmed as resistance factors.

Clinical relevance

Both HLA antigens A9 and B15 are potential candidates for periodontal risk assessment.

     

Influence of the bleaching interval on the luminosity of long-term discolored enamel-dentin discs

Objectives

The aim of this study is to investigate the influence of changing the sodium perborate-tetrahydrate (PBS-4) at a 4-day interval versus no change after 16 days of internal bleaching.

Materials and methods

Two hundred and ten bovine enamel-dentin discs were discolored for 3.5 years with 14 different endodontic materials. All groups with a discoloring index of ?E _(mean) ≥ 5.5 were included in the present investigation: ApexCal (APCA), MTA white + blood (WMTA+BL), Portland cement + blood (PC+BL), blood (BL), MTA gray (GMTA), MTA gray + blood (GMTA+BL), Ledermix (LED), and triple antibiotic paste containing minocycline (3Mix). Fourteen specimens of each group were randomly assigned into two treatment groups: (1) no change of the PBS-4 (n = 7); (2) change of the PBS-4 every 4 days (n = 7). Color measurements were taken at 10 different time intervals and the L*a*b* values were recorded with a spectrophotometer (VITA Easyshade® compact).

Results

In the group 3Mix, significantly better results were achieved by changing the bleaching agent every 4 days (P = 0.0049; q = 0.04), while the group WMTA+BL indicated better results by no change of the bleaching agent (P = 0.0222, q = 0.09). All remaining groups showed no statistical difference between the two treatment procedures.

Conclusions

Moderate discolorations can be successfully treated without changing the bleaching agent over a period of 16 days. Changing the sodium perborate-tetrahydrate every 4 days is preferred in case of severe discolored enamel-dentin discs only.

Clinical relevance

This approach may offer a reduced number of clinical appointments and a secondary cost reduction to the patient.

     

Anatomical relation between nasal septum deviation and oropharynx volume in different facial patterns evaluated through cone beam computed tomography

Introduction

The objective of this study was to establish the anatomical relation between nasal septum deviation (NSD) and oropharynx volume in different facial patterns using cone beam computed tomography (CBCT).

Methods

Ninety CBCT examinations were analyzed. InVivoDental software was used to evaluate cephalometric image reconstructions in terms of facial type, determined from cephalometric measurements indicative of growth direction; the presence of NSD was also evaluated. ITK-SNAP software was employed for delimitation of the oropharynx. Intra-examiner error methods were recorded. The results were subjected to parametric and non-parametric tests using Bioestat 5.0.

Results

A comparison of facial types revealed a significantly lower prevalence of NSD in the dolichofacial group compared with the brachyfacial and mesofacial groups (P = 0.0101 and 0.0149, respectively). In the total sample, there was a very strong positive relation between the presence of NSD and oropharynx space volume (P = 0.0162). The oropharynx volume was larger in all facial patterns in the presence of NSD.

Conclusion

The presence of NSD was not associated with facial type, although the oropharynx volume in patients with NSD increased. Therefore, deviation of the septum influences oropharynx volume.

     

Association of vdr,cyp27b1, cyp24a1 and mthfr gene polymorphisms with oral lichen planus risk

Objectives

The current study investigated the association between VDR EcoRV (rs4516035), FokI (rs2228570), ApaI (rs7975232) and TaqI (rs731236), CYP27B1 (rs4646536), CYP24A1 (rs2296241), and MTHFR (rs1801133) gene polymorphisms and risk of oral lichen planus (OLP) occurrence.

Materials and methods

The study group consisted of 65 oral lichen planus patients and 100 healthy blood donors in the control group. Single nucleotide polymorphisms were genotyped by real time PCR or PCR-restriction fragment length polymorphism (RFLP) method.

Results

Heterozygous as well as mutated genotype of vitamin D receptor (VDR) FokI (rs2228570) polymorphism was associated with increased oral lichen planus risk in comparison with wild type genotype (odds ratio (OR) = 3.877, p = 0.017, OR = 38.153, p = 0.001, respectively). A significantly decreased OLP risk was observed for heterozygous genotype of rs2296241 polymorphism in CYP24A1 gene compared with the wild type form (OR = 0.314, p = 0.012). VDR gene polymorphisms ApaI and TaqI were in linkage disequilibrium (D’ = 0.71, r ² = 0.22). Identified haplotype AT was associated with decreased OLP risk (OR = 0.592, p = 0.047).

Conclusion

Our results highlight the possible important role of VDR FokI (rs2228570) and CYP24A1 rs2296241 gene polymorphisms for oral lichen planus susceptibility.

Clinical relevance

Identification of new molecular biomarkers could potentially contribute to determination of individuals with OLP predisposition.

     

A preliminary study on plasma concentration achieved following intrapterygomandibular space injection of dexamethasone as a route of drug delivery with lignocaine inferior alveolar nerve block–correlation of clinical effects

Purpose

To determine the quantity of dexamethasone plasma concentration achieved following intrapterygomandibular space injection of dexamethasone when co-administered with inferior alveolar nerve block correlating with the clinical effects in the postoperative phase.

Objective

A preliminary prospective study to evaluate the dexamethasone plasma concentration achieved following intrapterygomandibular space injection of dexamethasone with 2% lignocaine inferior alveolar nerve block to achieve hemi-mandibular anesthesia for minor oral surgical procedures and derive clinical correlations.

Background

Dexamethasone is a glucocorticoid, chiefly used for the management of postsurgical sequelae like trismus and swelling in maxillofacial surgical practice. Conventionally, parenteral dexamethasone is administered via intravenous or intramuscular route. Intrapterygomandibular space injection is a novel route of steroid delivery described in literature. For minor oral surgical procedures in maxillofacial surgical practice requiring inferior alveolar nerve block, dexamethasone can be administered along with local anesthetic through a single injection as a mixture (twin mix).

Methods

Prospective double-blind randomized clinical trial was designed to evaluative plasma concentration of dexamethasone achieved following injection of a freshly prepared mixture of 1.8 ml of 2% lignocaine with adrenaline (1:200000) and 1 ml (4 mg) dexamethasone [2.8 ml solution of twin mix] in the pterygomandibular space. The 30 candidates included for the trial were randomly split into three study groups (ten each)—(1) control group (C); (2) intramuscular group (IM); (3) intraspace group (IS).

Results

The mean plasma dexamethasone concentration at 30 min postinjection in group IM was 226.41?±?48.67 ng/ml and for IS group it was 209.67?±?88.13 ng/ml. Post hoc (Bonferroni-Holm test) intergroup comparison for plasma dexamethasone concentration (IM and IS) was found statistically insignificant (P?=?0.605).

Conclusion

Intraspace route of drug administration can be utilized to deliver dexamethasonized local anesthetics safely with predictable clinical effects in the patients requiring mandibular minor oral surgery under local anesthesia.

     

Comparison between primary closure and skin grafts of the free fibula osteocutaneous flap donor site

Purpose

This study aimed to compare the size of skin paddles, the postoperative course, and donor site complications between primary closure and skin grafts of the free fibula flap donor site.

Methods

Thirty-five consecutive patients were enrolled. Medical records were retrospectively reviewed for risk factors for delayed healing, size of skin paddles, time to resumption of gait with a mobility aid and self-ambulation, early donor site morbidity, and late donor site complaints.

Results

The harvested skin paddles were significantly wider in the skin graft group than in the primary closure group (P?=?0.02), with no difference in length (P?=?0.1). The difference in time to resuming gait with a mobility aid was also significant (P?=?0.01), but not the time to self-ambulation (P?=?0.9). Two early donor site morbidities (5.7 %) and 12 late donor site complaints (34.3 %) were found. No significant difference in the incidence of early donor site morbidity was observed between two groups. Occurrence of late donor site complaints was not affected by any risk factors.

Conclusions

The width of the harvested skin paddle, but not the length, is one of factors involved in donor site closure. Resumption of gait with a mobility aid, but not self-ambulation, may be delayed in skin graft patients.

     

Early<Emphasis>-</Emphasis>life factors affect risk of pain and fever in infants during teething periods

Aim

This longitudinal study aimed to investigate the prevalence of teething-related pain and fever and the early-life factors that may affect the risk of experiencing these disturbances within the first 1.5 years of life.

Materials and methods

Participants were recruited (n = 1033) through the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort (n = 1237). Interviews were performed tri-monthly regarding the prevalence of teething pain and fever in children from 6 to 18 months of age. Crude and multivariable analyses were conducted using Poisson-log regression models.

Results

Prevalence rates for teething pain and fever were 35.5 and 49.9 % respectively. Multivariable Poisson regression analysis showed maternal second-hand tobacco smoke (SHS) exposure to increase the risk of both pain (mean ratio = 1.35; p = 0.006) and fever (mean ratio = 1.22; p = 0.025), whereas SHS exposure plus active smoking further increased risk of teething pain in the children (mean ratio = 1.89; p = 0.029). Delivery via Caesarean section increased risk of teething pain (mean ratio = 1.27; p = 0.033), while prenatal plasma vitamin D insufficiency lowered such a risk (mean ratio = 0.62; p = 0.012). Compared to Chinese infants, Indian babies exhibited lower risk of teething pain and fever (both p ≤ 0.001).

Conclusions

Early-life factors such as tobacco smoke exposure and vitamin insufficiency during pregnancy, ethnicity and childbirth via Caesarean section may significantly affect the child’s susceptibility to teething-related pain and fever.

Clinical relevance

Knowledge of prevalence and risk factors of teething disturbances may better equip primary caregivers and healthcare professionals to accurately detect teething-related local and/or systemic signs/symptoms and effectively facilitate tobacco cessation among pregnant women.

     

Synthesis and characterization of CaO-loaded electrospun matrices for bone tissue engineering

Objectives

This study aims to synthesize and characterize biodegradable polymer-based matrices loaded with CaO nanoparticles for osteomyelitis treatment and bone tissue engineering.

Materials and methods

Poly(ε-caprolactone) (PCL) and PCL/gelatin (1:1, w/w) solutions containing CaO nanoparticles were electrospun into fibrous matrices. Scanning (SEM) and transmission (TEM) electron microscopy, Fourier transformed infrared (FTIR), energy dispersive X-ray spectroscopy (EDS), contact angle (CA), tensile testing, and antibacterial activity (agar diffusion assay) against Staphylococcus aureus were performed. Osteoprecursor cell (MC3T3-E1) response (i.e., viability and alkaline phosphatase expression/ALP) and infiltration into the matrices were evaluated.

Results

CaO nanoparticles were successfully incorporated into the fibers, with the median fiber diameter decreasing after CaO incorporation. The CA decreased with the addition of CaO, and the presence of gelatin made the matrix very hydrophilic (CA = 0°). Increasing CaO concentrations progressively reduced the mechanical properties (p ≤ 0.030). CaO-loaded matrices did not display consistent antibacterial activity. MC3T3-E1 cell viability demonstrated the highest levels for CaO-loaded matrices containing gelatin after 7 days in culture. An increased ALP expression was consistently seen for PCL/CaO matrices when compared to PCL and gelatin-containing counterparts.

Conclusions

Despite inconsistent antibacterial activity, CaO nanoparticles can be effectively loaded into PCL or PCL/gelatin fibers without negatively affecting the overall performance of the matrices. More importantly, CaO incorporation enhanced cell viability as well as differentiation capacity, as demonstrated by an increased ALP expression.

Clinical significance

CaO-loaded electrospun matrices show potential for applications in bone tissue engineering.

     

Scientific Abstracts of 40th Annual Conference of Association of Oral and Maxillofacial Surgeons of India

Introduction

Bone marrow (BM) derived pleuripotent undifferentiated stem cells represent a promising population for supporting new concepts in cellular therapy.

Aim

The aim of this study is to evaluate the versatility of pleuripotent undifferentiated stem cells derived from BM aspiration and its applications in oral and maxillofacial surgical procedures.

Materials and Methods

A total of 30 patients out of which 15 were with hard tissue defects (cystic lesions n = 6, post surgical alveolar defects n = 4, peri implant defects n = 3, alveolar clefts n = 2) and 15 soft tissue lesions (leukoplakia and lichen planus n = 6, oral submucous fibrosis n = 7, post traumatic soft tissue loss n = 2) were included in the study on randomized clinical basis. The patients received autologous BM derived mononuclear cells which were being locally delivered into the lesion and followed up. The parameters used were (1) To compare and evaluate the bone regeneration by radiographic assessment at the end of 3rd and 6th month postoperatively. (2) Duration of the procedure. (3) Clinical improvement in the management of soft tissue lesions. (4) Assessment of wound healing by Vancouver burn scar assessment of wound. (5) Safety, postoperative infections and complications.

Results

For hard tissue lesions CT scans and OPG revealed adequate regenerated bone, bridging the defect after 3 months. Hounsfield units of regenerated bone after 6 months were more or less similar to native bone which was statistically significant (unpaired t test = p < 0.05). For soft tissue lesions (1) 7 cases of OSMF showed adequate clinical mouth opening (one way anova test = p < 0.05), reduction in burning sensation and blanching of mucosa, (2) 6 cases of leukoplakia and lichen planus and 2 cases of post traumatic soft tissue defects showed good clinical improvement by Vancouver burn scar assessment of wound index.

Conclusion

The study shows that there is a definite beneficial effect in bone regeneration and soft tissue wound healing with the use of BM-derived mononuclear cells.

     

Evaluation of a biomarker based blood test for monitoring surgical resection of oral squamous cell carcinomas

Introduction

The potential use of determination of biomarkers in blood for the monitoring of surgical removal of oral squamous cell carcinomas (OSCC) was evaluated using the epitope detection in monocytes (EDIM) technology.

Materials and methods

In tumor specimen, elevated Apo10 and transketolase-like 1 (TKTL1) expression was analyzed by immunohistochemistry. Apo10 and TKTL1 biomarkers have been used prospectively for EDIM blood test in patients with primary and/or recurrent OSCC (n = 92) before surgery and after curative tumor resection (n = 45).

Results

There were highly significant (p < 0.0001) correlations found between EDIM blood scores and the tissue expression of both biomarkers measured by immunohistochemistry (Apo10: n = 89/92, 97 %; TKTL1: n = 90/92, 98 %). EDIMApo10 and EDIM-TKTL1 scores were positive in 92 % (EDIM-Apo10: n = 85/92) and 93 % (EDIM-TKTL1: n = 86/92), respectively, in patients with OSCC before surgery. The combined score EDIM-Apo10/EDIM-TKTL1 increased significantly the detection rate of tumors to 97 % (n = 89/92). After surgery, the EDIM-TKTL1 and EDIMApo10 scores significantly decreased in 75.6 and 86.7 % of the patients (p < 0.0001), respectively, in the aftercare.

Conclusions

The correlation of TKTL1 and Apo10 immunohistochemistry with the blood test results indicates that the EDIM blood test could serve as a non-invasive diagnostic tool (liquid biopsy) to assess surgical removal of OSCC by determination of two biomarkers.

Clinical relevance

This is the first study that has been demonstrated a reliable and successful monitoring of OSCC cancer patients by a blood test. The specific and significant decrease of EDIM-TKTL1 and EDIM-Apo10 scores after surgery could serve as a new tool for monitoring surgical removal of OSCC.

     

Citrullination in the periodontium—a possible link between periodontitis and rheumatoid arthritis

Objectives

The aim of the present study was to assess human and bacterial peptidylarginine deiminase (PAD) activity in the gingival crevicular fluid (GCF) in the context of serum levels of antibodies against citrullinated epitopes in rheumatoid arthritis and periodontitis.

Materials and methods

Human PAD and Porphyromonas gingivalis-derived enzyme (PPAD) activities were measured in the GCF of 52 rheumatoid arthritis (RA) patients (48 with periodontitis and 4 without) and 44 non-RA controls (28 with periodontitis and 16 without). Serum antibodies against citrullinated epitopes were measured by ELISA. Bacteria being associated with periodontitis were determined by nucleic-acid-based methods.

Results

Citrullination was present in 26 (50 %) RA patients and 23 (48 %) controls. PAD and PPAD activities were detected in 36 (69 %) and 30 (58 %) RA patients, respectively, and in 30 (68 %) and 21 (50 %) controls, respectively. PPAD activity was higher in RA and non-RA patients with periodontitis than in those without (p = 0.038; p = 0.004), and was detected in 35 of 59 P. gingivalis-positive samples, and in 16 of 37 P. gingivalis-negative samples in association with high antibody levels against that species.

Conclusions

PAD and PPAD activities within the periodontium are elevated in RA and non-RA patients with periodontitis. PPAD secreted by P. gingivalis residing in epithelial cells may exert its citrullinating activity in distant regions of the periodontium or even distant tissues.

Clinical relevance

In periodontitis, the citrullination of proteins/peptides by human and bacterial peptidylarginine deiminases may generate antibodies after breaching immunotolerance in susceptible individuals.

     

Was molar incisor hypomineralisation (MIH) present in archaeological case series?

Objective

With respect to the unknown aetiology of molar incisor hypomineralisation (MIH), it is unclear whether this phenomenon was overlooked in the last century as a result of a high number of caries in children or if this developmental disorder was not present until then. Therefore, this study determined the presence of MIH in historical dentitions and teeth.

Materials and methods

Dental remains from late medieval (n = 191, twelfth–sixteenth century, Regensburg, Germany), post-medieval (n = 33, sixteenth–eighteenth century, Passau, Germany) and modern age archaeological skeletal series (n = 99, nineteenth–twentieth century, Altdorf, Germany) were examined for MIH. In addition, linear enamel hypoplasia (LEH), diffuse opacities, hypoplasia and Turner’s teeth were documented.

Results

MIH-related demarcated opacities or enamel breakdowns were found in only 15 (0.4 %) of the 3891 examined permanent teeth. Ten cases (3.1 %) from a total of 323 dentitions were classified as having MIH. In contrast, 98 individuals (30.3 %) showed LEH. Other enamel disorders were recorded in 64 individuals (19.8 %).

Conclusion

With respect to the low number of affected dentitions and teeth, MIH most likely did not exist or was at least rarely present in the investigated archaeological case series.

Clinical relevance

This study supports the hypothesis that MIH may be linked to contemporary living conditions or other health-related factors.

     

Osteosarcomas of the Head and Neck Region: A Case Series with a Review of Literature

Background

Osteosarcomas of head and neck region have unique biology and exhibit a clinical behavior and natural history that is distinct from osteosarcomas of the trunk and extremities. Our understanding of this malignant bone tumor is largely based on data from single institutions or compiled from registries, and hence the clinical practice guidelines seem confusing and conflicting.

Aims and Objectives

To analyze the demographic profile, disease characteristics and survival outcomes of osteosarcoma of head and neck region.

Materials and Methods

Retrospective analysis of the patients treated for osteosarcoma of head and neck region with curative intent in the period between the years 2001–2013 at a tertiary cancer center from South India.

Results

A total of 14 patients were treated in the said period with a mean age of 37 years. The most common site was mandible (n = 9 patients) followed by maxilla (n = 4) and paranasal sinuses (n = 1). Conventional osteoblastic variant of OS was the most common histological variant (n = 8) followed by the chondroblastic variant (n = 5). The median disease-free survival was 41.7 months, whereas the median overall survival of our patient cohort was 47.6 months. A formal analysis of various prognostic factors showed only postoperative margin positivity to be the single important factor affecting the survival outcomes.

Conclusion

Head and neck osteosarcoma that most commonly afflicts the jaw bones occurs in the fourth decade of life. Despite being a small series, our study does highlight the importance of achieving a margin-negative resection as a part of the multimodality treatment of head and neck osteosarcomas. Considering the relative paucity of data, there is a need for multi-institutional collaborative studies to refine the therapeutic strategies for the management of patients with head and neck osteosarcomas.

     

Cold plasma: a novel approach to treat infected dentin—a combined ex vivo and in vitro study

Objectives

The aim of this study was to evaluate the antimicrobial effect of cold plasma (CP) on infected dentin surfaces in vitro and ex vivo.

Materials and methods

To examine the effect of cold plasma on root surfaces, 24 root surfaces were infected with Streptococcus mitis. Specimens were randomly divided into three groups: Within the control group (C), root surfaces were rinsed with NaCl; root surfaces in the second group were additionally scaled and root planed (SRP), and in the third group, root surfaces were rinsed, scaled, root planed, and in addition, CP was applied (SRP + CP). To examine the effect of CP on root caries lesions (RCLs), 16 freshly extracted teeth with symmetrical carious lesions were equally divided into two groups. In the control group, carious lesions were treated with chlorhexidine (CHX), whereas CHX was applied in conjunction with CP in the test group (CHX + CP). For microbiological analysis, dentin samples were serially diluted and CFU counts were estimated after 24 h of incubation.

Results

Compared to C, mean CFU values for SRP and SRP + CP were significantly lower (p < 0.05). In addition, mean CFUs for SRP + CP were reduced to 0 and, therefore, significantly lower than SRP (2.98 log CFU/mL) alone (p = 0.000, Mann-Whitney U). Regarding RCLs, significantly lower mean CFU values were observed for CHX + CP when compared to CHX (4.45 vs. 2.67 log CFU/mL, p = 0.002, Mann-Whitney U test).

Conclusions

For disinfection of exposed root surfaces, the adjunctive application of CP is promising. In addition, the combined application of CHX + CP has the potential to disinfect root dentin surfaces.

Clinical relevance

It was shown that the combination of cold plasma with CHX is the best available option for the disinfection of root surfaces.

     

Postural assessment in class III patients before and after orthognathic surgery

Purpose

This study aimed to assess body posture before and after bimaxillary orthognathic surgery by photogrammetry in skeletal class III patients.

Methods

Thirty-one patients with skeletal class III dentofacial deformities (14 men, 17 women) who underwent orthodontic preparation for surgery were included in this non-randomized controlled trial. Of these, 15 who did not undergo orthognathic surgery during the period of this study served as controls. Postural assessment was performed by photogrammetry using SAPO® (Postural Assessment Software) based on anterior-, posterior-, and lateral-view images taken 1 month before and 4 months after bimaxillary orthognathic surgery with internal rigid fixation (or 4 months after the initial assessment, for the control group). The study was approved by PUCRS Research Ethics Committee, and written informed consent was obtained from all individual participants prior to their inclusion in the study.

Results

There was no significant difference between groups for age, gender, and GAP. In the intervention group, the right leg/hindfoot angle, which initially indicated a valgus deformity, normalized after intervention (P?<?0.048). Posterior displacement of the head (P?<?0.005) and trunk (P?<?0.004) were observed after intervention.

Conclusions

These results suggest that correction of class III dentofacial deformities by bimaxillary orthognathic surgery can produce systemic postural adjustments, especially posterior displacement of the head and trunk and knee and ankle valgus.

     

Fit of 4-unit FDPs from CoCr and zirconia after conventional and digital impressions

Objectives

To evaluate the marginal and internal fit of CAD/CAM-generated frameworks for 4-unit, fixed dental prostheses (FDPs) from zirconia (Z) and cobalt-chromium alloy (C) made with conventional (CI) and digital impressions (DI).

Materials and methods

A titanium model was digitized with an intraoral scanner (DI, LAVA? C.O.S.; 3M ESPE; Seefeld, Germany; n = 12). Additionally, 12 conventional impressions were taken, and referring plaster casts were digitized by a laboratory-scanner (CI, LAVA? Scan ST; 3M ESPE; n = 12). Frameworks were fabricated (3M ESPE) from cobalt-chromium (DI-C, n = 12; CI-C, n = 12) and zirconia (DI-Z, n = 12; CI-Z, n = 12) from the same datasets. A replica technique was applied to measure the accuracy. The Mann–Whitney U statistical test was applied to detect statistical differences between each material and methodology groups in terms of fit.

Results

Frameworks from DI-C (median 19.07 μm) showed significantly better marginal fit than CI-C (median 64.64 μm, p < 0.001). Frameworks from DI-Z (median 52.50 μm) showed significantly better marginal fit than CI-Z (median 72.94 μm, p = 0.001). Additionally, frameworks from DI-C showed a significantly better marginal fit than DI-Z (p < 0.001).

Conclusions

CI and DI led to a clinically acceptable marginal fit of 4-unit FDPs from cobalt-chromium and zirconia. DI leads to better marginal fit of the cobalt-chromium frameworks; however, no effect on zirconia was found.

Clinical relevance

The results indicate that DI is suitable for fabricating 4-unit, cobalt-chromium and zirconia frameworks with regard to fit requirements.