Incidence of three roots and/or four root canals in the permanent mandibular first molars in a Korean sub-population

Objectives

The purpose of this study was to evaluate the prevalence of three-rooted permanent mandibular first molars (PMFMs) with four canals and their morphological characteristics among a Korean population from using cone-beam computed tomography scans (CBCTs).

Materials and methods

Among the 705 CBCTs screened, 472 patient cases possessing at least one PMFM were identified. A total of 780 PMFMs were evaluated in axial section series to determine the number of roots and canals. The incidences of three-rooted PMFMs were compared with regard to gender and location. For distal root(s) with two canals, inter-orifice distances (IOD) between distobuccal and distolingual canals were measured at pulpal floor and furcation levels. The difference of IOD between males and females was also analyzed using chi-square tests.

Results

Among the 472 CBCTs of 225 females and 247 males, 84 females and 107 males were found to have at least one three-rooted PMFM. Among the 780 PMFMs, 191 PMFMs (24.5%, 89 of 397 left and 102 of 383 right) were found to have three roots. The prevalence of distal root(s) with two canals was 34.2% (267 of 780). From the molars with two distal canals, the mean IOD between distobuccal and distolingual canals at the pulpal floor level was 3.1 mm in males and 2.9 mm in females (p?=?0.0428).

Conclusions

The occurrence of three-rooted PMFMs among a Korean population was 24.5% and was higher than other countries and ethnicities. Understanding the prevalence of PMFMs with a distolingual root and/or canal in a Korean population and the IOD between distobuccal and distolingual canals may be useful for successful endodontic treatments.

Clinical relevance

Acknowledgment of potential incidence of three-rooted permanent mandibular first molars with four canals and the distance between two distal canals may increase the success rate of root canal treatment by reducing the missing canal untreated.     

Long-Term Outcomes of Cytomegalovirus Reactivation in Patients with Moderate to Severe Ulcerative Colitis: A Multicenter Study

Background/Aims

Cytomegalovirus (CMV) reactivations are frequently observed in patients with active ulcerative colitis (UC), and ganciclovir therapy is effective in patients with steroid-refractory UC. This study aimed to determine the long-term outcomes of CMV reactivation and the long-term therapeutic efficacy of ganciclovir treatment.

Methods

This retrospective multicenter study included a cohort of 72 patients with moderate-to-severe UC who were evaluated for CMV reactivation at the time of their initial UC flare. Colectomy, disease relapse, and the recurrence rate of CMV reactivation were investigated.

Results

The mean duration of follow-up for the 72 patients was 43.16±19.78 months (range, 1 to 67 months). The cumulative colectomy (log-rank, p=0.025) and disease flare-up rates (log-rank, p=0.048) were significantly higher in the CMV-positive group. Of the 11 patients who were successfully treated with ganciclovir in the initial treatment, three patients (27.3%) experienced CMV reactivation, and six patients (54.5%) experienced poor outcomes, such as the need for colectomy or a steroid-dependent state.

Conclusions

The patients who had CMV-reactivated UC showed poor outcomes at the long-term follow-up, and the long-term efficacy of ganciclovir therapy was marginal. Careful assessment is necessary for patients who exhibit evidence of CMV reactivation.     

Efficacy and Safety of TJP-008 Compared to 2 L PEG with Ascorbate in Colon Cleansing: A Randomized Phase 3 Trial

Background/AimsPolyethylene glycol (PEG)-based bowel preparations are effective cleansing agents for colonoscopy. However, they require relatively large volumes to be used even with agents such as 2 L PEG with ascorbate (2LPEG). This phase 3, randomized, single-blinded, multicenter, parallel-group study compared the efficacy of 1 L PEG with high-dose ascorbate, TJP-008, to 2LPEG.MethodsPatients undergoing colonoscopy were randomized (111) to receive TJP-008 as 1-day split dose (TJP-008-1) or 2-day split dose (TJP-008-2) regimen or to receive 2LPEG as a 2-day split dose regimen. Cleansing efficacy was evaluated using the Harefield Cleansing Scale. The primary endpoint was overall bowel cleansing success. Full analysis set (FAS) and per protocol set (PPS) analyses were performed.ResultsOf the 314 screened patients, efficacy was assessed in the following patient numbers (FAS/PPS) total (293/285), TJP-008-1 (98/94), TJP-008-2 (97/95), and 2LPEG (98/96). FAS revealed noninferiority between TJP-008 and 2LPEG with regard to overall success (TJP-008-2, 99.0%; TJP-008-1, 95.9%; 2LPEG, 94.9%; p=0.100 and p=0.733, respectively). PPS also showed noninferiority (p=0.721 and p=0.211, respectively). However, the PPS analyses showed a higher bowel cleansing score for TJP-008-2 for high-quality cleansing in the right colon (TJP-008-2 83.2% vs 2LPEG 62.5%; p=0.005).ConclusionsTJP-008 is a new low-volume cleansing agent with a colon cleansing efficacy comparable to that of standard 2LPEG that exhibits significant safety and tolerability.     

Zinc deficiency manifested by dermatitis and visual dysfunction in a patient with Crohn's disease

We report a case of Crohn's disease with low serum zinc concentration in a 26-year-old woman. She demonstrated acrodermatitis enteropathica and decreased visual acuity during total parenteral nutrition. Subsequent intravenous zinc supplementation resulted in alleviation of the skin lesions and improvement of visual acuity. This case supports the notion that depressed serum zinc in Crohn's disease may cause clinical manifestations, such as acrodermatitis enteropathica and retinal dysfunction, which may be correctable with zinc supplementation. (Received Nov. 12, 1997; accepted May 22, 1998)     

Contribution of nasal methicillin-resistant Staphylococcus aureus colonization to percutaneous endoscopic gastrostomy site infection and risk factors of wound infection]

BACKGROUND/AIMS: Peristomal infection is the most common complication of percutaneous endoscopic gastrostomy (PEG) insertion. Methicillin-resistant Staphylococcus aureus (MRSA) is the most commonly implicated organism of peristomal infection. The aims of this study were to determine the contribution of nasal MRSA to wound infection in PEG and the predictors of wound infection. METHODS: A prospective study was conducted on patients undergoing PEG between September 2003 and July 2005. All patients received antibiotics prior to PEG insertion. Nasal swabs were taken from a consecutive series of patients prior to PEG insertion. Wound status of the peristomal site were prospectively evaluated at day 1, 3, and 7 following the insertion of PEG. RESULTS: Thirty-one patients underwent PEG insertion (mean age, 66+/-16 years). Ten patients (32.3%) had MRSA-positive nasal swabs. Peristomal infection did not have any relationship with nasal MRSA colonization (p>0.05). Peristomal infection occurred in 4 (12.9%) cases. The rate of peristomal infections was significantly higher in patients with diabetes mellitus (p<0.05). CONCLUSIONS: Nasal MRSA colonization is not associated with the risk of peristomal infections in patients receiving antibiotics prior to PEG insertion. Diabetes mellitus might be the risk factor for peristomal infection after PEG insertion.     

The expression of matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs) and angiogenesis in relation to the depth of tumor invasion and lymph node metastasis in submucosally invasive colorectal carcinoma]

BACKGROUND/AIMS: Lymph node (LN) metastasis occurs in approximately 10% of patients with submucosally invasive colorectal carcinoma. This study was performed to determine the role of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) production and microvessel formation on the LN metastasis in submucosally invasive colorectal carcinoma. METHODS: A total of forty-one subjects with surgically resected submucosally invasive colorectal carcinoma were included in this study. Immunohistochemical staining of MMP-2, MMP-9, TIMP-1, TIMP-2, and urokinase-type plasminogen activator were performed. Angiogenesis was evaluated by counting the number of microvessels in each pathologic specimen as identified by CD34 immunohistochemical staining. RESULTS: The depth of submucosal invasion was not significantly correlated with the expression of MMP-2, MMP-9, TIMP-1, TIMP-2, or urokinase-type plasminogen activator, but the microvessel count was significantly correlated with the absolute depth of invasion (r=0.312, p<0.05). Upregulation of TIMP-2 was positively correlated with adjacent lymphatic invasion (p<0.05) and increased TIMP-2 expression was correlated with LN metastasis in submucosally invasive colorectal carcinoma (p=0.088). CONCLUSIONS: These results suggest that the expression of TIMP-2 and the microvessel count may be useful parameters for considering additional surgery after endoscopic treatment of submucosally invasive colorectal carcinoma.