Clinical retrospective study of dental implant removal: do patients who require implant removal desire implant prosthesis again?

BACKGROUND: This study investigated the causes of dental implant removal due to complications, and examined whether patients who had dental implant removal desired re-implant prosthesis treatments. MATERIAL AND METHODS: A retrospective case-control study was conducted on patients who had their dental implants removed. We investigated whether the removed dental implant was replaced with other implant prostheses. Age, sex, diabetes, smoking, implant site distribution, reason for implant removal, and blade and root-form implants were categorized as predictive variables. The outcome variable was desire for re-implantation or use of other prosthetic methods after implant removal. A logistic regression model was created to identify patient factors that could predict the re-implantation of dental prostheses after implant removal. RESULTS: A total of 215 dental implants were removed from 143 patients. The most common reason for implant removal was peri-implantitis that was identified in 165 implants. After implant removal, re-implantation was performed in 98 implants (45.6%). Bivariate analyses showed that age, diabetes, implant type, and reason for implant removal were associated with the desire for re-implanted prostheses. The multiple regression model revealed that age, implant type, and reason for implant removal were associated with an increased desire for re-implant prostheses after implant removal. CONCLUSIONS: Re-implantation of prostheses after the removal of dental implants was desired by patients who were younger, had implants placed in the root form, and had implants removed due to prosthetic-related complications.

Efficacy and safety of ustekinumab in Japanese patients with severe atopic dermatitis: a randomized, double-blind, placebo-controlled, phase II study.

BACKGROUND: Ustekinumab, a fully human monoclonal antibody against interleukin-12/23, may potentially be effective for severe atopic dermatitis (AD) treatment. OBJECTIVES: To evaluate efficacy and safety of ustekinumab 45 mg and 90 mg in patients with severe AD. METHODS: In this randomized, placebo-controlled, phase II study, Japanese patients (aged 20-65 years) with severe or very severe AD entered a 12-week double-blind treatment period during which they received (1 : 1 : 1) ustekinumab 45 mg, 90 mg or placebo subcutaneous injections at weeks 0 and 4, with follow-up until week 24. The primary efficacy end point was percentage change from baseline in Eczema Area and Severity Index (EASI) score at week 12. Major secondary efficacy end points included the proportion of patients achieving EASI 50, EASI 75, Investigator's Global Assessment score 0-1, change from baseline Atopic Dermatitis Itch Scale and Dermatology Life Quality Index. RESULTS: A total of 79 patients were randomized [ustekinumab 45 mg (n = 24), 90 mg (n = 28), placebo (n = 27)]. Ustekinumab treatment showed nonsignificant improvement in least square mean change from baseline EASI score at week 12 [45 mg: -38·2%, 95% confidence interval (CI) -21·02-19·51; P < 0·94 and 90 mg: -39·8%, 95% CI -21·84-17·14; P < 0·81] vs. placebo (-37·5%). A nonsignificant improvement in major secondary efficacy end points was observed in both ustekinumab groups vs. placebo. The most common treatment-emergent adverse events were nasopharyngitis and worsened AD (higher in placebo vs. ustekinumab groups). CONCLUSIONS: Ustekinumab 45 mg and 90 mg did not demonstrate meaningful efficacy in Japanese patients with severe AD. The treatment was generally well tolerated.

Does HMGB1 predict occult neck lymph node metastasis in early tongue carcinoma? A case-control study of 26 patients.

OBJECTIVE: This study examined whether the occurrence of late neck metastasis in early tongue squamous cell carcinoma can be predicted by evaluating HMGB1 (high mobility group box 1) expression in the primary lesion. METHODS: A case-control study was conducted. The cases comprised 10 patients with late neck metastasis. The controls consisted of 16 patients without recurrence. All were examined immunohistochemically for HMGB1 protein expression. The odds ratio for late neck metastasis in relation to HMGB1 was estimated. RESULTS: RESULTS for HMGB1 were dichotomised into positive staining scores (score, 5-7) and negative scores (0-4). Six cases (60 per cent) and four controls (25 per cent) were HMGB1-positive. Although no significant result was seen, compared with HMGB1-negative patients the odds ratio for late neck metastasis in HMGB1-positive patients was 3.8 (95 per cent confidence interval, 0.6-26.5) after adjusting for other factors. CONCLUSION: In the present study, immunohistochemical study of HMGB1 in early tongue squamous cell carcinoma did not appear to be very useful for predicting occult neck metastasis. Further study is necessary to clarify the relationship between HMGB1 expression and late neck metastasis in early tongue squamous cell carcinoma.

Stromal cells promote bone invasion by suppressing bone formation in ameloblastoma.

AIMS: To study the stromal variation and role of stromal-tumour cell interaction in impaired bone formation as well as enhanced bone resorption in ameloblastoma. METHODS AND RESULTS: Four types of stroma were observed histologically; fibrous, desmoplastic, myxoid and myxoid with hyalinization. Osteoblast and osteoclast were counted using haematoxylin and eosin sections and immunohistochemistry with CD68. After histomorphometric analysis, only fibrous and myxoid types of stroma were distinctly identified. Secreted frizzled-related peptide (sFRP)-2, transforming growth factor-beta 1 and receptor activator of nuclear factor-kappaB ligand (RANKL) revealed strong expression in myxoid type compared with the normal stroma. Bone morphogenetic protein (BMP)-2 was negative in myxoid type, but positive in normal stroma. Fibrous-type stroma showed weak expression of all antigens except RANKL compared with myxoid type. CONCLUSIONS: The results suggest that stroma does not act only in bone resorption, but also in the suppression of new bone formation. sFRP-2 is the main factor for impaired bone formation. The expression of markers related to osteoclastogenesis and suppression of osteoblast formation is higher in myxoid-type than in fibrous-type stroma. Tumour cells create a favourable environment for impaired bone formation by secreting sFRP-2 as well as bone resorption by secreting RANKL and interleukin-6.

Lack of B-RAF mutations in head and neck squamous cell carcinoma.

B-RAF is one of the most commonly mutated oncogenes in human cancer. However, the mutation status of B-RAF has not been established completely in HNSCC. We have analysed the mutation status of the kinase domain of the B-RAF gene (exons 11 and 15) in 91 Japanese HNSCC patients as well as 12 HNSCC cell lines. DNA was extracted and amplified by PCR. Mutations were then analysed by SSCP mutation detection method. Since V600EB-RAF constitutes 90 % of the mutations identified in B-RAF in human cancers, we also used MASA analysis to specifically detect this mutation in exon 15 of B-RAF. Using both methods, no mutation was found in both exon 11 and 15 in all patients and cell lines. Mu tations are absent or rare in the kinase domain of B-RAF in Japanese HNSCC. However, more studies are still needed to determine its usefulness as a target for molecular therapy in these patients.