Treatment effects of R-appliance and Anterior Inclined Bite Plate in Class II, Division I malocclusion

OBJECTIVES: The purpose of this study was to compare the effects of a differently designed functional appliance (R-appliance) and the Anterior Inclined Bite Plate (AIBP) in Class II Division I (Cl II Div I) cases. MATERIAL AND METHODS: Fifty patients (28 girls, 22 boys) were chosen for the study: 25 patients (13 girls, 12 boys) with mean age of 10.4±0.8 years were treated with R-appliance for 11±2 months, the other 25 patients (15 girls, 10 boys) with mean age of 9±1.2 years were treated with AIBP for 10±2 months. All patients had Cl II Div I malocclusion due to mandibular deficiency. Lateral cephalograms were analyzed at the beginning (T1, T 1) and end of the study (T2, T 2). RESULTS: Paired T-test showed that SNB had a significant increase in both groups. The same test revealed that IMPA was reduced in R-appliance for 3.1±4.7 (p<0.01), but it was increased for 0.1±5.1 (p<0.9) in AIBP group. T-test showed that the inter-group difference of IMPA was statistically significant (p<0.05). SNA showed an increase in both groups (p<0.9). Ar-B and Ar-Pog showed an increase in both groups and the differences between them were statistically significant. CONCLUSIONS: Mandibular advancement was achieved in both groups, but R-appliance achieved this result without lingual tipping of lower incisors.

Cervical vertebrae anomalies in patients with class III skeletal malocclusion.

BACKGROUND AND OBJECTIVE: Studies have documented that deviations in skeletal components such as the cranial base, the mid-facial complex and the mandible may be associated with morphological factors in patients with class III skeletal malocclusion. Furthermore, deviations in head and neck posture may be associated with the class III skeletal malocclusion. The purpose of this study was to compare cervical vertebrae morphology in patients with class III skeletal malocclusion and adults with normal occlusion. MATERIALS AND METHODS: This case-control study assessed 30 patients with class III skeletal malocclusion (aged 17-30 yrs, with normal vertical growth pattern and ANB<0) were compared with 46 controls (aged 17-30 years, with normal vertical growth pattern, ANB=3+1). Cervical vertebrae anomalies (fusion anomalies and posterior arch deficiency) were assessed via evaluation of their lateral cephalograms. The t- test and Fisher's exact test were used for statistical analysis. RESULTS: In the study group, 73.3% had fusion of the body of the cervical vertebrae, while in the control group only 32.6% showed fusion. The fusion in the control group was between C2 and C3 in all cases; whereas, in the study group, fusion was seen between C2-C3, C3-C¬4 or C4-C¬5. Additionally, cervical column deviations occurred significantly more often in the study group compared to the control group (P<0.001). CONCLUSION: Class III skeletal malocclusion may be associated with fusion of cervical vertebrae and deviation of the cervical column.

Treatment effects of R-appliance and anterior inclined bite plate in class II, division I malocclusion.

OBJECTIVES: The purpose of this study was to compare the effects of a differently designed functional appliance (R-appliance) and the Anterior Inclined Bite Plate (AIBP) in Class II Division I (Cl II Div I) cases. MATERIAL AND METHODS: Fifty patients (28 girls, 22 boys) were chosen for the study: 25 patients (13 girls, 12 boys) with mean age of 10.4±0.8 years were treated with R-appliance for 11±2 months, the other 25 patients (15 girls, 10 boys) with mean age of 9±1.2 years were treated with AIBP for 10±2 months. All patients had Cl II Div I malocclusion due to mandibular deficiency. Lateral cephalograms were analyzed at the beginning (T1, T 1) and end of the study (T2, T 2). RESULTS: Paired T-test showed that SNB had a significant increase in both groups. The same test revealed that IMPA was reduced in R-appliance for 3.1±4.7 (p<0.01), but it was increased for 0.1±5.1 (p<0.9) in AIBP group. T-test showed that the inter-group difference of IMPA was statistically significant (p<0.05). SNA showed an increase in both groups (p<0.9). Ar-B and Ar-Pog showed an increase in both groups and the differences between them were statistically significant. CONCLUSIONS: Mandibular advancement was achieved in both groups, but R-appliance achieved this result without lingual tipping of lower incisors.

The effect of mandibular tongue cribs on dentoskeletal changes in patients with Class II Division 1 malocclusions.

AIM: To investigate the effect of a modified tongue crib appliance in Class II Division 1 patients with anterior tongue thrust and mandibular deficiency. METHODS: Twenty-three patients (14 females, 9 males) with a mean age of 10.09 ± 1.02 years, a moderate Class II Division 1 occlusion due to a mandibular deficiency, and a mean overbite of -1.1 ± 0.8 mm were treated with a mandibular tongue crib device. Pre- and posttreatment lateral cephalograms were obtained and traced, and various angular and linear variables were measured. These measurements were compared using the paired t test. RESULTS: The statistical assessment indicated that SNB, facial angle, B-VL, Pog-VL, and interincisal angle increased significantly. IMPA, 1-SN, ANB, and Wits appraisal were significantly decreased (P<.05). The changes of Jarabak Index, SN-MP, SNA, and Y-axis were not significant. In addition, the overjet was reduced. CONCLUSION: During the mixed dentition phase, a tongue crib appliance in the mandible is helpful to impede tongue thrust and stimulate mandibular growth.

[Cyclooxygenase 2 and carcinogenesis]. / Cyclo-oxygénase 2 et carcinogenèse.

The membrane glycoprotein Cox2 is regulated at transcriptional and post-transcriptional levels by pro-inflammatory agents, cytokines, growth factors, oncogenes, and tumor-promoters. Cox2 is expressed during early stages of colorectal carcinogenesis from the premalignant adenoma stage, and adenocarcinomas of stomach, colon, breast, lung and prostate. Its expression is detected in neoplastic, inflammatory, endothelial and stromal cells. Cox2 is involved in the conversion of arachidonic acid into prostaglandins and thromboxanes, as well as the synthesis of malonaldehyde (MDA, a mutagen) and the production of hydrogen peroxide, which promotes carcinogenesis. The Cox2 products act in turn on serpentine receptors coupled to heterotrimeric G-proteins (R-TXA2, R-PG) that are connected to signaling elements implicated in oncogenesis. Thus, Cox2 plays a key role in early stages of carcinogenesis by promoting the proliferation of tumoral cells and their resistance to apoptosis, as well as angiogenesis. tumor cell invasion and setting up of the metastatic process. These mechanisms establish the rationale behind the therapeutic targeting of Cox2 in human solid tumors.

[Cyclooxygenase 2 and carcinogenesis]. / Cyclo-oxygénase 2 et carcinogenèse.

The membrane glycoprotein Cox2 is regulated at transcriptional and post-transcriptional levels by pro-inflammatory agents, cytokines, growth factors, oncogenes, and tumor-promoters. Cox2 is expressed during early stages of colorectal carcinogenesis from the premalignant adenoma stage, and adenocarcinomas of stomach, colon, breast, lung and prostate. Its expression is detected in neoplastic, inflammatory, endothelial and stromal cells. Cox2 is involved in the conversion of arachidonic acid into prostaglandins and thromboxanes, as well as the synthesis of malonaldehyde (MDA, a mutagen) and the production of hydrogen peroxide, which promotes carcinogenesis. The Cox2 products act in turn on serpentine receptors coupled to heterotrimeric G-proteins (R-TXA2, R-PG) that are connected to signaling elements implicated in oncogenesis. Thus, Cox2 plays a key role in early stages of carcinogenesis by promoting the proliferation of tumoral cells and their resistance to apoptosis, as well as angiogenesis, tumor cell invasion and setting up of the metastatic process. These mechanisms establish the rationale behind the therapeutic targeting of Cox2 in human solid tumors.