Biomedical subjects

Chi-Cheng Tsai

Publications and source records attributed to Chi-Cheng Tsai.

At least 19 recordsLinked to original sources

PubMed2006

Ingredients contribute to variation in production of reactive oxygen species by areca quid.

Areca quid (AQ) chewing has been implicated an independent risk factor for the development of oral cancer. Taiwanese areca quid (AQ) refers to a combination of areca nut (AN), lime, and inflorescence of Piper betle Linn. (IPB) or Piper betle leaf (PBL). Studies of AQ in other countries reported that AN extract combined with lime generates reactive oxygen species (ROS), such as hydroxyl radical (HO.), known to be a contributing factor in oral mucosa damage. To determine whether HO. is formed in the oral cavity during AQ chewing, the formation of meta-tyrosine (m-Tyr) and ortho-tyrosine (o-Tyr) from l-phenylalanine (Phe) was confirmed. It was demonstrated that combined aqueous extracts of AN, lime, metal ions (such as Cu2+ and Fe2+), and IPB or PBL produced HO.. Thus, the yield of HO. significantly increases when higher amounts of IPB or lime are added and also when Cu2+ and Fe2+ are increased. Further, the omission of any one of these ingredients significantly reduces the formation of HO.. Our results found that chewing AQ with IPB generated significantly higher HO. than chewing AQ with PBL, and may result in greater oxidative damage to the surrounding oral mucosa.

Adult↗

PubMed2006

Factors associated with quitting areca (betel) quid chewing.

OBJECTIVES: The purpose of this study was to provide useful data for a future abstinence project by identifying the factors related to quitting areca (betel) quid chewing. METHODS: The study was cross-sectional. Data on demographic variables, psychological factors and substance-use behaviors were collected via questionnaires from 326 participants. RESULTS: Multiple logistic regression analysis indicated that the areca/betel quid chewers who were less educated (OR = 0.58, 95% CI = 0.34-0.98) were least likely to try to give up. Among the chewers who tried to quit, those employed as full-time drivers (OR = 2.24, 95% CI = 1.14-4.39), who had drinking habits (OR = 2.41, 95% CI = 1.24-4.66), and who preferred to chew only betel quid wrapped with leaf (OR = 4.44, 95% CI = 1.99-9.90) were more likely to fail. Chewers who successfully quit had a higher internal health locus of control compared with those who failed to quit (one-point increments, OR = 0.94, 95% CI = 0.90-0.98). CONCLUSIONS: The results suggest that health educators and researchers can better influence people's chewing behavior if the importance of chewers' education level, job type, substance use (i.e. drinking habits, type of betel quid), and level of health locus of control are all taken into consideration when devising interventions.

Adult↗

PubMed2006

Reducing, by pulse width modulation, the curing temperature of a prototype high-power LED light curing unit.

Third-generation LEDs have high irradiance and efficiency, but the associated temperature rise is potentially hazardous to the pulp of teeth. We evaluated, during composite polymerization, the irradiance and temperature rise of a prototype high-power LED light curing unit (LCU) with optimal pulse width modulation (PWM), and then compared the results with four off-the-shelf high-power LCUs. A cavity was prepared in a tooth, and a composite resin layer was applied and cured. For each LCU, the irradiance and temperature changes at the pulp-dentin junction were measured. Microhardness (Vickers hardness) of cured composite samples was measured for each LCU. Our prototype had a final temperature of 36.4 +/- 1.3 degrees C and irradiance of 1,182 +/- 1 mW/cm2. The unit with the highest temperature had a temperature of 48.7 +/- 1.2 degrees C and an irradiance of 1,194 +/- 1 mW/cm2. Based on the results of the present study, it was shown that PWM technology reduced the curing temperature while retaining the polymerization effectiveness of a high-power LED LCU.

Analysis of Variance↗

PubMed2005

Interleukin-12 and interleukin-16 in periodontal disease.

The immune system plays an important role in the pathological process of periodontitis. Interleukin-12 (IL-12) is produced by monocytes, macrophages and neutrophils. These cells are proinflammatory infiltrates in periodontitis tissues. High IL-12 will contribute to the immune reaction to Th1 type. IL-12 is an inducer of INF-r production. IFN-gamma itself can also activate IL-12 production. Lipopolysaccharides (LPS) of periodontopathogens are also activators of IL-12. Interleukin-16 (IL-16) can cause the high affinity of IL-2 receptors on CD4+ cells and is chemotaxis to Th1 cells and CD4+ T cells. IL-16 can stimulate monocytes to produce proinflammatory cytokines and is highly associated with inflammation including arthritis, enteritis and allergic rhinitis. However, the information on IL-12 and IL-16 in periodontitis is not clear. In this study, 105 GCF samples were collected from 19 periodontal disease patients and 6 healthy ones. The clinical periodontal indices, the habits of cigarette smoking and alcohol drinking were recorded. ELISA was used to determine the levels of IL-12 and IL16 in the GCF. In the non-smoking/non-alcohol-drinking individuals: (1) the total amount of IL-12 (but not IL-16) was significantly higher in chronic periodontitis (CP) sites than gingivitis (G) or healthy (H) sites; (2) the diseased sites (CP + G) had a significantly higher total amount of IL-12 (but not IL-16) than the H sites. Among CP sites, both the concentration and total amount of IL-16 (but not IL-12) were significantly higher in alcohol drinkers/cigarette smokers as compared to the non-drinkers/non-smokers. CP sites of the drinkers/smokers also had significantly deeper probing pocket depth than sites of those without these two habits. IL-12 and IL-16 may be related to the pathogenesis of periodontal disease, but within the periodontitis sites, IL-16 may be related to disease severity in alcohol drinkers/smokers.

Alcohol Drinking↗

PubMed2005

Topographic study of root trunk type on Chinese molars with Class III furcation involvements: molar type and furcation site.

This study investigated the relationship between root trunk length and prognosis for molars with furcation involvement. Molars with furcation involvement were obtained from 169 patients affected with periodontitis. The test group consisted of 174 hopeless molars screened from a total of 441 molars with Class III involvement; the remaining 267 molars formed the control group. Both arches showed a significantly higher missing rate for teeth with a long root trunk length (type C) in second molars (41.3% and 32.4% in the maxilla and mandible, respectively), with a high degree of Class III furcation involvement for the test group (extracted hopeless or poor prognosis), compared to first molars (9.9% and 0.9% in the maxilla and mandible, respectively). Both arches had a significantly higher prevalence of long root trunk lengths in the second molars compared to first molars, irrespective of furcation site. Although first molars had an early and higher prevalence of Class III furcation involvement than second molars, the latter reached a significantly higher missing rate. Molars with longer root trunk lengths had a higher risk for poor prognosis than shorter root trunks when teeth were affected by Class III furcation involvement. For extracted furcation-involved maxillary second molars that failed to respond to periodontal therapy, long root trunk length (C) accounted for the greatest prevalence at the mesial furcation site (41.8%), followed by the distal (33.0%) and buccal sites (25.2%); the greatest prevalence of root trunk length C was found at the lingual (47.9%) and buccal furcation sites (45.1%) of mandibular second molars. When a molar with root trunk type C has a Class III involvement, the prognosis is poor; for the disease to reach that level, greater amounts of attachment must be destroyed.

Adult↗

PubMed2004

Pure titanium casting into zirconia-modified magnesia-based investment molds.

OBJECTIVE: Molten titanium is highly reactive with common mold materials at elevated temperatures. The aim of this investigation was to improve the accuracy of pure titanium casting by adding unreactive zirconia into magnesia-based investment material. METHODS: An automatic thermal expansion laser-recording machine (TEM-1000/Pantos, Nippon Co.) was used to measure thermal expansion of investment materials. An automatic argon-casting machine (Castmatic-S, Iwatani Co.) was used to cast pure titanium samples. A stereomicroscope was used (Nikon SM-2T, Japan) to measure marginal discrepancy on a metal die. A Vickers microhardness indenter (MXT-50, Matsuzawa Seiki Co.) determined the Vickers hardness (VH) of the titanium samples. Interfacial reactivity of the titanium was evaluated with an X-ray diffractometer (Rigaku D/max VIII, Tokyo, Japan). A dental X-ray machine was used to examine internal porosity of the castings. Data was analysed with paired t-test (p < 0.05), ANOVA/Tukey's HSD test (p < 0.001) and Spearman's correlation test (p < 0.05). RESULTS: Addition of 5.0-6.0 mass% of zirconia to a magnesia-based investment material significantly increased its thermal expansion value (p < 0.05). ANOVA indicated significant marginal discrepancy differences within the zirconia-added group (p < 0.001). There was a significant correlation between thermal expansion at 750 degrees C and marginal discrepancy (p < 0.05). The addition of zirconia decreased interfacial reactivity and the VH of titanium. SIGNIFICANCE: Under appropriately adjusted conditions, the addition of zirconia to magnesia-based mold materials may be used to produce high quality pure titanium castings.

Analysis of Variance↗

PubMed2004

Betel nut chewing: the prevalence and the intergenerational effect of parental behavior on adolescent students.

PURPOSE: To explore the betel nut chewing prevalence among students, analyze the probability and the odds ratio of ex-chewers and current chewers, as well as the correlation between parental behavior characteristics and those of adolescents chewing betel nut. METHODS: A cross-sectional survey was designed and 10,288 Taiwanese students answered the questionnaires in 2002. A structured questionnaire included information about betel nut chewing behavior among the adolescent students, sociodemographic data, and the betel nut chewing practice among parents or classmates. Samples were randomly chosen from each cluster of different types of schools in various areas. Three different grade levels of the first, second, and third grade (ages 16-18 years) were selected. Frequency distribution was used to analyze the prevalence among adolescent students, and Chi-square tests were used to compare the differences of betel nut chewing behavior among genders and the effect of parental behavior and socioeconomic factors. Logistic regression was used to analyze the odds ratio of the prevalence of adolescent students' betel nut chewing in the different types of schools and by gender. RESULTS: When the parents' marriage was not successful, or was of a lower social status, a higher incidence of adolescent betel nut chewing was observed. It was easy to experience betel nut chewing in adolescence if either parent chewed betel nut. The prevalence of betel nut chewing among male students was higher than female students and among vocational school students than general school students. The odds ratio of agricultural school students to general school students was highest of all the ex-chewers and current chewers from different types of schools. CONCLUSIONS: Betel nut chewing behavior is related to the effect of parental behavior on adolescent students. Apparently, it is indicated that there is a significant intergenerational effect of the parent's behavior on their children's behavior.

Adolescent↗

PubMed2004

Important prognostic factors of long-term oropharyngeal carcinoma survivors in Taiwan.

In Taiwan, a clear gender difference emerges for rates of oropharyngeal carcinoma incidence. The purpose of this study was to identify the gender differences and clinical factors associated with oropharyngeal carcinoma survival rates in Taiwan. We analyzed the 5-year survival rates of 8114 subjects diagnosed with oropharyngeal carcinoma between 1987 and 1994. The Cox proportional-hazards model identified clinical characteristics for gender according to oropharyngeal carcinoma death and all-cause death outcomes. The 5-year survival rates were significantly lower for males than females (p < 0.0001). The adjusted hazard ratio of males versus females was 1.54 (95% CI: 1.36-1.74) for oropharyngeal carcinoma death and 1.44 (95% CI: 1.31-1.58) for all-cause death. Gender and other clinical characteristics (i.e. diagnostic age, anatomic site, morphologic type, and treatment modality) play important roles in oropharyngeal carcinoma survival. We suggested that Taiwanese males have high proportion of betel quid chewing and that this is associated with the gender differences.

Adenocarcinoma↗

PubMed2004

The investigation of glutathione peroxidase, lactoferrin, myeloperoxidase and interleukin-1beta in gingival crevicular fluid: implications for oxidative stress in human periodontal diseases.

BACKGROUND: Human periodontal diseases are inflammatory disorders that are the result of complex interactions between periodontopathogens and the host's immune response. Two important and interrelated factors are involved in the pathophysiological progression of periodontal diseases, i.e. the activation of immune system and the production of oxygen radicals and their related metabolites. Increased production of oxygen radicals may contribute to oxidative stress, which is reported to be involved in many diseases, including periodontal diseases. OBJECTIVES: The objective of this study was to investigate glutathione peroxidase, lactoferrin and myeloperoxidase, which play an essential role in free radical production and defenses, and the proinflammatory cytokine interleukin-1beta (IL-1beta), which is important in the regulation of immunological and inflammatory reactions in human periodontal diseases. METHODS: Gingival crevicular fluid (GCF) samples were collected from 27 subjects, 19 periodontitis patients and eight healthy controls, ranging in ages from 24 to 62 years. Clinical parameters were recorded. GCF glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta were analyzed by enzyme-linked immunosorbent assays (ELISA). RESULTS: The periodontitis sites exhibited significantly greater total amount of glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta than healthy sites. Total amount of glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta was positively correlated with plaque index, gingival index, probing depth and probing attachment level (p < 0.05). CONCLUSION: The imbalance between the levels of myeloperoxidase/IL-1beta and glutathione peroxidase/lactoferrin could result in tissue damage of reactive oxygen species (ROS) in periodontitis which is initiated and perpetuated by the chronic insults of periodontopathogens.

Adult↗

PubMed2003

Betel nut chewing and related factors in adolescent students in Taiwan.

OBJECTIVE: To investigate the prevalence of betel nut chewing and related factors among adolescent students in general, manufacturing, commercial, agricultural and medical technology schools in Taiwan. To make suggestions regarding how health authorities can reduce the number of students taking up the habit. MATERIALS AND METHODS: A cross-sectional survey was designed, and 10,288 students answered the questionnaire. RESULTS: Significantly more male than female students were betel nut chewers. The less urbanized areas were also associated with a higher prevalence of the habit. The prevalence of the habit grew with increasing age. By analysing betel nut chewing behaviour, it was found that most students started chewing betel nuts because of curiosity, and most obtained betel nuts from their friends and classmates. Betel nut chewing behaviour is definitely related to peer pressure. Most betel nut chewers did not realize that withdrawal could lead to physiological reactions, and they were ignorant of any risk to health even though they were compulsive betel nut chewers. The health-harming behaviours of both smoking and drinking were found in many betel nut chewers, particularly smoking. CONCLUSION: This study confirmed the need for a health education programme dealing with the health risks of betel nut chewing for students at risk. The health authorities could also develop a programme for betel nut chewing among Taiwan's adolescent students, emphasizing the dangers of this habit.

Adolescent↗

PubMed2003

Characterization of atmospheric PM10 and related chemical species in southern Taiwan during the episode days.

The concentrations of atmospheric PM10 on days with episodes of pollution were examined at four different sampling sites (CC, DL, LY, and HK) in southern Taiwan. The related to particulates water-soluble ionic species (Na+, K+, Mg2+, Ca2+, NH4+, Cl-, NO3-, SO4(2-)), carbonaceous species (EC and OC) and metallic species (Zn, Ni, Pb, Fe, Mn, Al, Si, V) were also analyzed. On the episode days of this study, the PM10 mass concentration ranged from 155 to 210 microgm(-3), from 150 to 208 microgm(-3), from 182 to 249 microgm(-3), and from 166 to 228 microgm(-3) at CC, DL, LY, and HK, respectively. The results indicate that the dominant water-soluble species were SO4(2-), NO3-, NH4+, and Cl- at the four sampling sites on these days. Moreover, the high sulfate and nitrate conversion values (SOR and NOR) presented herein suggest that secondary formations from SO2 to SO4(2-) and from NO2 to NO3- are present in significant quantities in the atmosphere of southern Taiwan on episode days. In particular, high SOR and NOR verified that both SO4(2-) and NO3- dominated the increase of atmospheric PM10 concentration in southern Taiwan on episode days.

Air Pollutants↗

PubMed2003

Topographic study of extracted molars with advanced furcation involvement: furcation entrance dimension and molar type.

This study investigated the topography of the furcation entrance dimension (FED) on molars with advanced furcation involvement (FI). The sample pool consisted of 169 maxillary and mandibular molars from a group of 165 individuals with severely advanced periodontal destruction. The subjects included men and women aged 24 to 84 years (mean, 47.8 +/- 7.2 years). The FEDs of the maxillary buccal, mesial, and distal surfaces as well as the mandibular buccal and lingual surfaces were measured under a stereomicroscope and clarified into grades I (FED < 0.55 mm), II (0.55-0.75 mm), and III (> 0.75 mm) using automatic grading system software designed by our research associates. The differences and relationships among molar location, furcation site, and FED grade were analyzed using the chi-square test. There was a significant difference among buccal (BFED), mesial (MFED), and distal (DFED) FEDs in both the maxillary first (chi2(4) = 58.915, p < 0.001) and second (chi2(4) = 66.839, p < 0.001) molars. The relationship between molar type and FED grade was statistically significant for both the BFED (p < 0.001) and the DFED (p < 0.001) of maxillary molars, as well as for both the BFED (p < 0.0001) and LFED (p < 0.0001). The difference in FED grade between the first and second molars was statistically significant in both maxillary (p < 0.001) and mandibular (p < 0.0001) molars. There was a significant relationship between FED grade and tooth location at molars with advanced FI.

Adult↗

PubMed2003

Effect of zirconia-modified magnesia investment on the casting of pure titanium.

Several investigations have examined magnesia-based investments for pure titanium casting. However, the thermal expansion value was insufficient at low casting temperatures and high interfacial reactivity occurred at high casting temperatures. The purpose of this investigation was to modify a magnesia-based investment by adding a heat-resistant mold material, zirconia, in different ratios to produce a more accurate titanium casting. The thermal expansion value was measured using a new precise automatic laser recording machine and pure titanium was cast using an argon casting machine. The marginal accuracy was measured using a stereomicroscope and the interfacial reactivity of the titanium was evaluated using X-ray diffraction analysis. The results indicate that adding different amounts of zirconia to a magnesia-based investment can increase its thermal expansion value and decrease the interfacial reactivity of the titanium. Maximal thermal expansion in the zirconia-modified investments significantly increased by 5-6 weight % (wt%) and peaked at 1.62% expansion. Selevest with 5 wt% zirconia had the smallest mean marginal discrepancy, 21.70 microm at 750 degrees C. Analysis of variance indicates significant differences in marginal discrepancy between zirconia-modified investments (p < 0.001). Adding zirconia can also decrease the interfacial reactivity of the titanium. The data indicated that proper amounts of zirconia (5-6 wt%) added to a magnesia-based investment can produce a more accurate and less interfacial reactive pure titanium casting.

Dental Casting Investment↗

PubMed2003

Potential role of vascular endothelial growth factor, interleukin-8 and monocyte chemoattractant protein-1 in periodontal diseases.

Host-mediated immunoinflammatory pathways activated by bacteria lead to destruction of the periodontal connective tissues and alveolar bone. The objective of this study was to elucidate the activation of the inflammatory processes in periodontal disease by quantitative assessment of cytokines and periodontopathogens. Gingival crevicular fluids (GCF) and subgingival plaque samples were collected from patients with chronic periodontitis and gingivitis and from periodontally healthy sites. Vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), and interleukin 8 (IL-8) in GCF were analyzed by enzyme-linked immunosorbent assay. Periodontopathogens, including Bacteroides forsythus, Campylobacter rectus, Porphyromonas gingivalis and Prevotella intermedia, were analyzed by immunofluorescence and dark-field microscopy. There was significantly more VEGF and IL-8 in chronic periodontitis and gingivitis sites than in periodontally healthy sites. There were significant positive correlations between the concentrations and total amounts of VEGF and IL-8 in chronic periodontitis and gingivitis sites, and between the levels of periodontopathogens and the total amounts of VEGF, MCP-1 and IL-8. These data indicate that inflammatory processes induced by periodontopathogens and the activation of certain cytokines (VEGF, MCP-1, IL-8) in periodontal diseases may be relevant to host-mediated destruction in chronic periodontitis.

Adult↗

PubMed2003

Gm (23) allotypes and Fcgamma receptor genotypes as risk factors for various forms of periodontitis.

OBJECTIVES: Given the diversity of the distribution of the Gm (23) allotypes and FcgammaR genotypes in different ethnic groups, it was our purpose to examine their clinical significance in periodontitis in Taiwan. MATERIAL & METHODS: Genomic DNA of 50 patients with chronic periodontitis (CP), 30 patients with generalized aggressive periodontitis (G-AP) and 74 healthy controls were harvested. The Gm (23) allotypes were determined by radial immunodiffusion test, and the FcgammaR IIa (CD32) and IlIb (CD16) genotypes were determined by polymerase chain reaction-based allele-specific oligonucleotide hybridization. RESULTS: The overall carrier rate of the Gm (23+) allotype was higher than 85%, and the Gm (23-) allotype was statistically over-represented in patients with CP compared to the controls. There were no differences in the distributions of the three genotypes of FcgammaR IIa and IIIb among the three tested groups. The frequency of the R131 allele of the FcgammaR IIa polymorphisms was higher in G-AP than in CP when R/H allelic frequencies (p = 0.01) were examined by the chi2 test. CONCLUSION: The Gm (23-) allotype might be a potential risk factor for CP. Although the R131 allele of FcgammaR IIa occurred more frequently in G-AP than in CP, its clinical significance could not be justified in this study.

Adult↗

PubMed2003

Immunoglobulin G profiles in different forms of periodontitis.

BACKGROUND: Races and Gm(23) allotypes can modify the serum levels of IgG subclasses. The average serum levels of IgG subclasses of African-Americans have been reported to be higher than those of Caucasians in both healthy young adults and patients with aggressive periodontitis; Gm(23)-positive subjects generally had higher IgG2 levels than Gm(23)-negative subjects. OBJECTIVE: We examined serum immunoglobulin G (IgG) concentrations in Taiwanese patients with different forms of periodontitis. METHODS: The serum levels of four IgG subclasses were determined by enzyme-linked immunosorbent assay and Gm(23) allotypes were verified by radial immunodiffusion tests in 50 patients with chronic periodontitis, 30 patients with aggressive periodontitis, and 74 healthy controls. RESULTS: There were no differences in the concentrations of four IgG subclasses in patients with chronic periodontitis compared with age-matched controls. However, in subjects younger than 35 years, levels of IgG2 were significantly elevated in patients with aggressive periodontitis compared with controls. We also found significant differences in IgG2 levels within the control group when stratified by age (< or = 35 years and > 35 years). Gm(23) allotypes were not correlated with the serum levels of IgG2 in either patient group. CONCLUSION: Microbial challenge might not provoke significant changes in systemic IgG response in patients with chronic periodontitis. However, in patients with aggressive periodontitis, IgG2 levels were increased when compared with age-matched controls. Gm(23) allotypes had no influence on IgG2 levels in well-established generalized chronic periodontitis or aggressive periodontitis.

Adult↗

PubMed2003

Lifestyle and psychosocial factors associated with chronic periodontitis in Taiwanese adults.

BACKGROUND: The development of chronic periodontitis (CP) is a multifactorial process and variation in severity cannot be explained by just a few risk factors. The aims of this study were: 1) to explore the lifestyle and psychosocial factors of CP patients and 2) to estimate the proportion of total CP cases attributable to one or more risk factors considered. METHODS: A case-control study of 250 cases of CP patients and 250 controls were matched by age (within 3 years) and gender. Complete dental examinations were performed based on the clinical criteria for CP for both groups. Structured questionnaires were conducted to collect lifestyle and psychosocial factors. Multivariate logistic regression was applied to assess the association between risk factors and chronic periodontitis. RESULTS: Conditional multivariable logistic regression analysis showed that toothbrushing frequency (odds ratio [OR]: 5.77, if rarely; OR: 3.50, if once a day), mental illness (OR: 5.32, if Chinese Health Questionnaire scores were > or = 6), and smoking (OR: 3.93, if pack years smoked was > 21) are significantly and independently associated with chronic periodontitis. In addition, all these variables reflected a dose-response effect (P trend = <0.001, 0.004, and 0.005, respectively). CONCLUSIONS: For Taiwanese adults, 36.10% of CP cases were presumably attributable to toothbrushing frequency, mental illness, and smoking. These three factors should be the first priorities in establishing a preventive program to improve the periodontal health status.

Adult↗

PubMed2002

Treatment of intrabony defects associated with interradicular root proximity/fusion in molar furcations.

To treat furcation involvement is a crucial challenge to periodontists, not only because of the limitation in pocket reduction by osteoplasty and apically positioned flap, but also because of the unpredictability in regenerative approaches. Therefore, if the first molar is absent and the second molar has to be retained strategically for prosthetic reasons, very few alternatives besides nonsurgical/surgical debridement can be taken in treating the furcation of the second molar, where the interradicular root proximity and fusion frequently occur. On the other hand, root amputation/hemisection has long been considered a contraindication in treating furcations with two close roots; however, this impression is only empirical. A series of clinical cases involved in the treatment of intrabony defects associated with interradicular root proximity and fusion by root amputation/hemisection has been reported. Without any help of regenerative material, thorough root debridement and pocket reduction were attained. Based on these cases, we suggested that the cut surface created by odontoplasty during root amputation was compatible for periodontal healing and the extraction socket provided striking potential for defect repair. We re-examined the clinical feasibility and benefit of treating intrabony defects associated with interradicular root proximity and fusion in molar furcations by root amputation/hemisection, and suggested that its role should be favorably reconsidered on case basis. The short-term success in periodontal and prosthetic aspects needed to be further evaluated at long-term follow-up.

Adult↗