The effect of different mandibular dentures on antagonistic maxillary ridge

PURPOSE: Is to evaluate the antagonistic, maxillary ridge resorption for different prosthetic modalities mainly mucosa-supported mandibular complete overdentures, combined mucosa implant-supported mandibular complete overdenture, and lower conventional complete dentures. MATERIALS AND METHODS: Fifteen completely edentulous patients were divided into 3 groups; 5 patients each. Group I patients received maxillary conventional denture and mandibular overdentures retained by magnet attachment on 2 implants (mainly mucosa-supported overdenture). Group II patients received maxillary conventional denture and mandibular overdentures retained by bar attachment on 2 implants (combined mucosa implant-supported overdenture). Group III patients received upper and lower conventional complete denture. All patients were evaluated clinically and radiographically immediately after insertion and after 1 and 2 years. Panoramic radiographic film was used to evaluate the antagonistic maxillary ridge resorption. RESULTS: Indicated a more pronounced annual bone resorption of the antagonistic maxillary ridge after 2 years in patients with conventional complete denture wearers when compared with patients with combined mucosa implant-supported mandibular complete overdenture and mainly mucosa-supported mandibular complete overdenture groups. CONCLUSION: Using a combined mucosa implant-supported mandibular complete overdenture the amount of antagonistic maxillary alveolar bone resorption increases when compared with the mainly mucosa-supported complete overdenture.     

Evaluation of anterior maxillary alveolar ridge resorption when opposed by the transmandibular implant

Fifteen edentulous patients with complaints regarding denture comfort and/or function were treated with the transmandibular implant. All patients were restored with conventional maxillary dentures opposed by implant-supported removable prostheses. Two to 4 years after surgery, these patients were evaluated for vertical and horizontal maxillary bone loss with a radiographic analysis developed by the authors. With this technique, attention was focused on vertical alveolar ridge resorption in the anterior maxilla. Although the sample size was small, the findings from this study indicate that vertical bone loss in the anterior maxilla does occur when a maxillary denture is opposed by an implant-supported overdenture. Comparison of these results with a previous study that evaluated anterior maxillary resorption when a complete maxillary denture opposed natural mandibular anterior teeth and a distal extension removable partial denture demonstrated no statistically significant difference.     

Cocktail Impression Technique: A New Approach to Atwood’s Order VI Mandibular Ridge Deformity

The management of highly resorbed ridge has always posed a challenge to the prosthodontist for years. Obtaining consistent mandibular denture stability has long been a challenge for dental profession. In particular, Atwood's Order V and Order VI pattern of bone resorption is associated with difficulties in providing successful dentures. Stability of lower denture in such cases is usually the distinguishing factor between success and failure. This article outlines a combination of different impression techniques to improve mandibular denture stability in an atrophic mandibular ridge, keeping in mind the prevention of further ridge resorption.     

Surgical and prosthetic treatment of the atrophic mandible

Two vestibuloplasty methods and a muscle-formed method for improving the retention and stability of complete mandibular dentures were compared in 19 edentulous patients with advanced mandibular bone resorption. The resorptive changes in the alveolar crest and any relapse in the extended vestibule after surgery were monitored for 2 yr. Simultaneous production of the first new complete dentures, to which the labial plate is added during the surgical procedure, and firm circummandibular fixation during primary healing will guarantee the best surgical and prosthetic results. This order of treatment also eliminates unnecessary surgical procedures. A muscle-formed method for extending the baseplate of a complete mandibular denture was found to be a useful alternative for patients with highly advanced mandibular bone resorption.     

Surgical and prosthetic treatment of the atrophic mandible

Abstract — Two vestibulopiasty methods and a muscle-formed method for improving the retention and stability of complete mandibular dentures were compared in 19 edentulous patients with advanced mandibular bone resorption. The resorptive changes in the alveolar crest and any relapse in the extended vestibule after surgery were monitored for 2 yr. Simultaneous production of the first new complete dentures, to which the labial plate is added during the surgical procedure., and firm circummandibular fixation during primary healing will guarantee the best surgical and prosthetic results. This order of treatment also eliminates unnecessary surgical procedures. A muscle-formed method for extending the baseplate of a complete mandibular denture was found to be a useful alternative for patients with highly advanced mandibular bone resorption.     

骨转换标志物对于牙槽嵴重度吸收患者咀嚼效能与两种改良牙合型全口义齿戴用的影响

目的 对骨转换标志物正常和升高的牙槽嵴重度吸收的无牙颌患者,分析两种改良牙合型（长正中牙合型、舌向集中牙合型）全口义齿的戴用与咀嚼效能的关系,以期为临床全口义齿修复中牙合型的选择提供参考。 方法 选取85例（男45例,女40例）牙槽嵴重度吸收的无牙颌患者,采用随机数字表法随机选用两种改良牙合型全口义齿（长正中牙合型全口义齿、舌向集中牙合型全口义齿）治疗方案。电化学发光免疫法测量血清中骨转换标志物——Ⅰ型前胶原N端前肽（P1NP）和Ⅰ型胶原交联C 末端肽（CTX）的水平,分为骨转换标志物正常组及升高组。义齿戴用3个月后,吸光度法测定咀嚼效能,多因素方差分析不同骨转换标志物测量值的患者不同类型改良牙合型全口义齿的戴用与咀嚼效能的关系。 结果 骨转换标志物（P1NP和CTX）正常组的患者,不同类型改良牙合型（长正中牙合型、舌向集中牙合型）全口义齿的戴用与其咀嚼效能的关系无统计学差异。而骨转换标志物（P1NP和CTX）升高组患者,不同类型改良牙合型全口义齿的戴用与其咀嚼效能的差异有统计学意义（P<0.01）,与戴用舌向集中牙合型全口义齿的患者相比,戴用长正中牙合型全口义齿的患者具有更高的咀嚼效能。 结论 骨转换标志物较高的患者,选用长正中牙合型全口义齿会得到相对更高的咀嚼效能。骨转换标志物有望成为牙槽嵴重度吸收的无牙颌患者选择戴用不同改良牙合型全口义齿时的参考指标。     

Two implants for all edentulous mandibles

Complete dentures have always been a poor substitute for natural teeth. Mandibular complete dentures frequently cause pain and discomfort, accelerated residual bone resorption, while failing to restore effective chewing. The provision of two implants to stabilise the mandibular complete denture can result in significant improvements.     

Maxillary anterior and mandibular posterior residual ridge resorption in patients wearing a mandibular implant-retained overdenture

The mandibular implant-retained overdenture could improve masticatory function compared to the conventional complete denture. However, increased forces exerted by the overdenture could increase residual ridge resorption of the maxillary anterior and mandibular posterior areas. The aim of this study was to compare the effect of the mandibular implant-retained overdenture using two or four dental implants, or the conventional complete denture on resorption of the residual ridge of the maxillary anterior and mandibular posterior areas over a period of 10 years. In total, 120 patients, 30 patients treated with an overdenture on two implants (two-implant group), 30 patients with an overdenture on four implants (four-implant group) and 60 patients treated with a conventional full denture (conventional group), participated in this study. On panoramic radiographs, made before and 10 years after treatment, proportional area measurements were applied to determine changes in bone height. After 10 years, a statistically significant amount of bone resorption had occurred in the anterior maxilla in the two-implant group and in the four-implant group. A significant amount of bone resorption had occurred in the posterior mandible in all three groups. There were no statistically significant differences between the groups in both areas. Patients presented large individual differences. It is concluded that patients rehabilitated with implant-retained mandibular overdentures are not subjected to more residual ridge resorption in the anterior maxilla when compared to patients wearing a conventional full denture. Regarding the mandibular posterior residual ridge, resorption was irrespective of wearing an implant-retained mandibular overdenture or a conventional mandibular denture.     

Telescopic Overdenture Supported by a Combination of Tooth and an Implant: A Clinical Report

The conventional modality of treatment of partial edentulousness with reduced number of teeth was to render them complete edentulous and provide them complete denture or an overdenture with support of few remaining teeth. The goal of maintenance of roots are to prevent alveolar bone resorption, provide better load transmission, maintain sensory feedback and achieve better stability of denture with emphasis on psychological aspect of not being completely edentulous. Over the recent past titanium dental implants have been successfully used as tooth replacement with predictable results. A combination of tooth and implant support is well documented for fixed partial dentures but rarely for overdentures. This clinical report aims at evaluation of tooth root and implant supported mandibular overdenture treatment with telescopic coping.     

Extensive fixed partial dentures on mandibular canine teeth: a 5-year recall study

Twelve patients were followed for 5 years after treatment with a 12-unit cantilever fixed partial denture on the mandibular canines opposed by a complete maxillary denture. Two fixed dentures had to be removed, one because of an abutment tooth root-fracture and one because of rapid marginal bone loss in a terminal stage of leukemia. Caries and periodontal lesions were rare, but other complications, principally related to endodontics, occurred. All complications were amenable to standard treatment procedures. Extensive mandibular cantilever fixed partial dentures may be used in the rehabilitation of patients with a very reduced dentition and a history of difficulties in adapting to removable dentures.     

Similarities in resorption patterns of maxillary and mandibular ridges

The differences in the posterior arch widths between opposing maxillae and mandibles were studied in 100 edentulous denture-wearing patients. Panoramic radiographs of 67 of these patients were used to assess the percentage of mandibular height reduction from that considered present before extractions. Comparisons between posterior maxillary and mandibular arch widths, reductions in mandibular height, and edentulous age accompanied by denture wearing were made. The following conclusions emerged: 1. The mandible does not progressively widen as its opposing maxillae becomes narrower, nor does a progressive incremental increase occur in posterior maxillomandibular width relations with increased resorption or resorptive age. 2. The arch width of the mandible exceeds the arch width of the maxillae in the molar region by an average of 6 to 7 mm after sufficient resorption establisheds a definitive alveolar crest. This difference remains the same regardless of the amount of resorption or resorptive age. 3. The progressive and irreversible mandibular alveolar resorption rate is greatest in the earlier stages of edentulism and slows with loss of bone, longevity of edentulism, and attendant wearing of dentures.     

Assessment of states of dentures and interest in implant-retained prosthetic treatment in 55-year-old edentulous Finns

Abstract – One hundred and fifty 55-year-old edentulous subjects (104 women and 46 men) were interviewed. Materials, conditions, functional stabilities, and occlusions of complete dentures, and resorption of alveolar crests were recorded and assessed. The dentures were in good condition in 52% of subjects. Occlusion was correct in 45% of cases. Every fifth mandibular denture exhibited good functional stability. The mean age of dentures in good condition and functionally stable was statistically significantly lower than the mean age of dentures poor in these respects. Severe alveolar resorption contributed to poor functional stability of dentures ( P = 0.0068 (maxilla), P = 0.0023 (mandible)) and to incorrect occlusion ( P =0.0177). Good agreement was noted between objective and subjective opinions of denture function ( p = 0.01 (maxillary denture), P = 0.01 (mandibular denture)). Although oral rehabilitation with endosseous implants is common and, objectively, needs for such treatment existed, only 22 subjects (15%) who had recently had their dentures renewed and were experiencing problems with functional stability were interested in implant-retained overdentures.     

Posterior jaw bone resorption in osseointegrated implant-supported overdentures

For several years, osseointegrated implant-supported overdentures have been used in the rehabilitation of full edentulism with excellent results, at least in the lower jaw. This study involved 3 groups of patients with different prosthetic reconstructions: (1) mandibular overdentures supported by 2 implants connected by a bar (30 patients), (2) mandibular fixed prostheses supported by 4-6 implants (25 patients) and (3) mandibular complete dentures without implant support as controls (85 patients). The primary aim of this study was to examine on orthopantomograms (by means of the area index to minimize distortion and magnification errors), posterior mandibular ridge resorption in the 3 treatment groups. The present data demonstrated a minimal posterior mandibular ridge resorption in patients with fixed implant-supported prostheses. A more considerable posterior ridge resorption was observed in the complete denture group and especially in the overdenture wearers. For the latter, the annual posterior jaw bone resorption after the post-extraction remodeling period of 6 months, was 2- to 3-fold that of full denture wearers. When patients were edentulous for more than 10 years, the difference between the 2 latter groups disappeared. It is suggested that although the overdenture design on 2 implants offers advantages from a financial and failure rate point of view, its indications in younger patients should cautiously be evaluated in a long-term perspective concerning posterior mandibular bone resorption.     

Effect of a denture adhesive on mandibular denture dislodgment

The cineradiographic technique was used to assess the retention of complete mandibular dentures during chewing. The study comprised ten complete-denture wearers with severe alveolar ridge resorption in the mandible. Two cineradiographic recordings were performed, with and without a denture adhesive spread onto the base of the mandibular denture. The analysis of the cineradiographic films disclosed a significant decrease in denture dislodgment, expressed as maximal value, when a denture adhesive was used. The mean dislodgment also decreased, but not significantly.     

Complete denture fabrication using piezography and CAD-CAM: A clinical report

To provide maxillary and mandibular complete dentures for a patient with severe ridge resorption, the denture space was recorded using the piezography technique. After the piezographic space was scanned, a virtual tooth arrangement and festooning were performed within the space using computer-aided design software. The denture bases were milled from a polymethylmethacrylate resin block using computer-aided manufacturing, and commercially available denture teeth were bonded with resin adhesive. Using the piezography technique described, physiologically appropriate complete dentures were fabricated based on the neutral zone concept.     

Risk factors associated with denture stomatitis in the United States

BACKGROUND: This study reports denture stomatitis (DS) prevalence from a large USA probability sample from the National Health and Nutrition Examination Survey, 1988-1994 (NHANES III). METHODS: Oral examinations were performed on 3450 individuals 18-90+ years of age (mean: 59.2; SD: 0.50 years), 57.7% male and 42.3% female. Multivariable logistic regression models were fitted for DS using sociodemographic, denture quality, blood analytes, alcohol and tobacco use, history of diabetes, and current antibiotic use as covariates. Odds ratios (OR), adjusted for other covariates in each model (AOR) are presented. RESULTS: Of 3450 removable denture wearers, 963 (27.9%) had DS. DS prevalence was associated with wearing maxillary (AOR: 6.20) and mandibular (AOR: 5.21) complete dentures continuously; smoking >/=15 cigarettes day (maxillary complete: AOR = 1.31; mandibular complete: AOR = 1.50; maxillary partial: AOR = 2.04); vitamin A deficiency (mandibular complete: AOR = 5.97; maxillary partial: AOR = 5.67; mandibular partial: AOR = 24.42). Maxillary dentures with inadequate relines had approximately half the OR of DS than those with adequate relines (maxillary complete: AOR = 0.42; mandibular complete: AOR = 0.50). CONCLUSIONS: Denture stomatitis prevalence is associated with the amount of tissue covered by dentures, low vitamin A levels, cigarette smoking, and constant denture wear.     

A histomorphometric analysis on bone dynamics in denture supporting tissue under continuous pressure

The purpose of this study was to investigate bone dynamics under a denture base, in relation to the intensity of continuous pressure exerted through it to the denture supporting tissue. Two hundred and fifty male rats of Wistar strain were divided into five groups, four of which wore experimental dentures to load continuous pressure of 0.0, 1.0, 10.0 or 20.0 kPa to the molar region of the hard palate. The fifth group was the non-denture-wearing group. Fluorescent labelled palatal bone tissue was stained with Villanueva bone stain and was prepared for the undecalcified grinding section. In the 0.0 kPa group whose mucosa was covered with denture base, although no bone resorption was observed, bone formation was inhibited up to 4 weeks after the denture insertion. Bone dynamics in the 1.0 kPa group was similar to those in the 0.0 kPa group. In the 10.0 and 20.0 kPa groups, bone resorption was observed until 3 and 2 weeks after the denture insertion, and the amount of bone resorption (AoBR) was 24 +/- 17 and 35 +/- 21 lm, respectively. After bone resorption in these groups, although osteoid formation increased earlier than 0.0 kPa group, mineralization showed a similar time course with 0.0 kPa group. In conclusion, bone dynamics under a denture base caused by continuous pressure exerted through it was revealed to show a time course depending on the intensity of the initial pressure. Amount of bone resorption was also revealed to correspond to the intensity of the initial pressure. Bone formation following bone resorption did not cause equivalent recovery of the bone surface level to the level observed in the case without bone resorption.     

应用电子散斑干涉术对下颌单侧游离缺失修复体受载的实验研究

目的对下颌单侧游离缺失后三种不同修复体的运动及其受力状态进行试验性研究。方法首次采用电子散斑干涉术（ｅｌｅｃｔｒｏｎｉｃｓｐｅｃｋｌｅｐａｔｅｒｎｉｎｔｅｒｆｅｒｏｍｅｔｒｙ）对单端固定桥、铸造三臂卡环及ＲＰＩ卡环的可摘局部义齿进行垂直加载测试，观察显示的实时散斑干涉条纹图并测量相应各截面牙槽骨的离面位移（ｏｕｔｏｆｐｌａｎｅｄｉｓｐｌａｃｅｍｅｎｔ）。结果表明三种修复体修复后均有利于应力的传递，相应截面牙槽骨的离面位移减少。其中单端固定桥修复后相应牙槽骨的离面位移量最小，ＲＰＩ卡环较三臂卡环可摘局部义齿修复后相应牙槽骨的离面位移量稍大。结论电子散斑干涉术特别适用于测量小而不规则牙槽骨表面的变形情况。合理选择适应证，单端固定桥是一种良好的修复方式。     

Effect of mucostatic and selective pressure impression techniques on residual ridge resorption in individuals with different bone mineral densities: A prospective clinical pilot study

Statement of problem

Although different impression techniques have been advocated for complete denture prosthodontics, objective studies that predict their effect on alveolar bone resorption are lacking.

Management of Compromised Ridges: A Case Report

Complete denture therapy is an age old form of dental treatment. Ridge atrophy poses a clinical challenge towards the fabrication of a successful prosthesis. Extreme resorption of the maxillary and mandibular denture bearing areas results in sunken appearance of cheeks, unstable and non retentive dentures with associated pain and discomfort. This article describes the step by step rehabilitation procedure of a patient with atrophic ridges using a hollow maxillary complete denture with cheek plumpers attached to it and the recording of neutral zone to ensure a stable mandibular denture.