Degree Of Residual Ridge Resorption Research Articles

Facial aesthetic evaluation of rehabilitation effects in edentulous patients with varying degrees of residual ridge resorption by 3D stereophotogrammetry.

Residual ridge resorption impairs patients' satisfaction with complete denture (CD) treatment, but influence of bone resorption on the aesthetic rehabilitation of edentulous patients still remains unclear due to insufficient quantitative investigations. To quantitatively evaluate the effects of residual ridge resorption on facial aesthetic reconstruction in elderly edentulous patients. According to radiological examination, a total of 19 edentulous subjects were categorised into two groups, atrophic patients (APs) and non-atrophic patients (NAPs). Before CD treatment and 3months after treatment, patients were asked to complete the Orofacial Esthetic Scale (OES). The changes in facial appearance were measured by 3D stereophotogrammetry, and the facial parameters of two groups were compared. The patient's subjective satisfaction of oro-facial aesthetics and 3D objective assessment of facial appearance improved after CD treatment. Subnasale-gnathion (Sn-Gn) significantly increased from 60.13±3.91mm to 62.27±3.82mm. After rehabilitation, glabella-subnasale (G-Sn)/Sn-Gn, nasolabial (Cm-Sn-Ls) and mentolabial (Li-Sm-Pg) significantly decreased and were closer to normal values. Moreover, the subtraction value between G-Sn/Sn-Gn and normal value before treatment of APs and NAPs was 14.47±8.04% and 6.94±3.69%, respectively (P=.026), while after treatment, the values decreased to 10.61±6.33% and 3.86±2.31% (P=.013), respectively. The increased volume of lips and cheeks played an important role in the facial aesthetic reconstruction of edentulous patients. NAPs tended to have more attractive faces after CD treatment, as their facial profile parameters (G-Sn/Sn-Gn and Cm-Sn-Ls) were closer to normal Chinese with well-balanced faces.

Morphometric characteristics of cortical and trabecular bone in atrophic edentulous mandibles

Adaptations of the alveolar ridge after tooth loss have been well described. However, studies on the morphometric characteristics of cortical bone are rare; hence, this study of human atrophic edentulous mandibles was undertaken. Total cortical area, porosity, and thickness, and the percentage of cortical area in the complete mandibular area as well as in an area (height, 10 mm) starting at the most caudal point of the trabecular compartment and extending in the coronal direction were determined in 185 thin ground sections of edentulous mandibles (incisor region, 49; premolar region, 76; molar region, 60; 95 from females and 90 from males; mean age, 78.2 years, SD ± 7.8 years; Caucasian donors; cause of death: cardiovascular disease). Further, mandibular height and width and degree of residual ridge resorption (RRR) were recorded. The percentage of cortical area in the complete mandibular area increased with increasing RRR. Yet, evaluation of the 10-mm caudal portion corresponding to the basal part of the mandibular body did not confirm these changes in cortical bone. Cortical porosity and thickness decreased from the mesial to the distal region. Cortical porosity was unaffected by RRR, while cortical thickness increased, mainly at lingual aspects. In conclusion, cortical bone remained stable in different degrees of RRR except for some modulations in the lingual aspects. Changes in the relative composition between cortical and trabecular bone are due to loss of height and total area, mainly at expense of trabecular bone area, but not to adaptations of the cortical bone.

Change of polished surface contours on mandibular complete denture base in different residual ridge resorption situation: a pilot study

To investigate the profile of mandibular denture polished surface in edentulous patients with different residual ridge resorption (RRR) using neutral zone record. Twenty randomly selected edentulous patients with different category of RRR were investigated, which were divided into three groups according to ridge resorption grade and the relationships between upper and lower jaws: group 1: Class I edentulous patients (n = 6), group 2: Class II edentulous patients (n = 7), group 3: Class III edentulous patients and crossbite jaw relationship (n = 7). All subjects were asked to perform sufficient functional movement with silicon registration material in their mouth to record the shape, which were interpreted as the ideal shape of denture polished surface. Three-dimensional laser scanner was used to record the data of the outline of the maxillary and mandibular ridge and the silicon record of the polished surface. Digital model reconstruction was then conducted on the workstation. Sagittal surface of the model in the cut-in point on first molar and first premolar was made and data of the outline of these surfaces was collected. Both the buccal and the lingual polished surfaces were concave, straight or slight protuberant and inclined respectively in group 1, 2 and 3. The average angles between the horizontal and the lingual polished surface were (80.40 +/- 3.51) degrees, (90.38 +/- 2.71) degrees and (96.59 +/- 5.00) degrees respectively. The polished surfaces were changed with different progress of RRR in edentulous patients. It was suggested that the degree of residual ridge resorption and the relationship between upper and lower jaws should be considered when clinicians design the polished surface of denture.

Fluoridated drinking water, oestrogen therapy and residual ridge resorption.

Anamnestic and clinical investigations were made for 230 postmenopausal women to determine whether the alveolar height in edentulous jaws is associated with the time that the subjects have consumed artificially fluoridated drinking water. The duration of possible hormone replacement therapy was also considered. The results of the present study support those of previous studies which have shown that the effect of systemic factors dominates the final stage of residual ridge resorption. According to this study, artificially fluoridated water may also reduce the degree of residual ridge resorption, the impact of which first becomes manifest when most of the ridge has disappeared.

Fluoridated drinking water, oestrogen therapy and residual ridge resorption

summary Anamnestic and clinical investigations were made for 230 postmenopausal women to determine whether the alveolar height in edentulous jaws is associated with the time that the subjects have consumed artificially fluoridated drinking water. The duration of possible hormone replacement therapy was also considered. The results of the present study support those of previous studies which have shown that the effect of systemic factors dominates the final stage of residual ridge resorption. According to this study, artificially fluoridated water may also reduce the degree of residual ridge resorption, the impact of which first becomes manifest when most of the ridge has disappeared.

Skeletal osteopenia and residual ridge resorption

Increased residual ridge resorption resulting from postmenopausal skeletal osteopenia has been a long-standing clinical assumption. This study was conducted to determine the relationship between the degree of residual ridge resorption, sex, and the age of the patient. The technique of measuring mandibular resorption uses panoramic radiographs as described by Wical and Swoope. Six readers received technique instructions and were then tested for uniformity. An analysis of variance demonstrated no significant difference between readers (p > 0.10). A random selection of 459 radiographs of edentulous patients were then measured by using a blind technique to determine the amount of residual ridge resorption. Analysis of this data demonstrated a significantly larger percentage of women with class 3 (severe) residual ridge resorption (p < 0.01) but this difference could not be related to the occurrence of menopause.