Association between occlusal force distribution in implant overdenture prostheses and residual ridge resorption

Does occlusal morphology of artificial teeth improve chewing of removable dentures wearers? A systematic review and meta-analysis

PURPOSE

This systematic review aimed to verify whether anatomic, semi-anatomic, or nonanatomic occlusal morphology of artificial teeth improves the masticatory function of complete or removable partial denture wearers.

MATERIALS AND METHODS

According to the PICO strategy, six databases and the grey literature were searched to identify randomized (RCT) and non-randomized clinical trials (N-RCT) comparing masticatory function, in terms of masticatory performance and efficiency, and muscle activity as primary outcomes; and patient-reported results (O) in individuals using removable dentures (P) with different occlusal morphologies of artificial teeth (I/C). Masticatory ability, satisfaction with the prosthetic treatment, and oral health-related quality of life (OHRQoL) were evaluated as secondary outcomes. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB 2.0) for RCT and Risk of Bias for non-randomized studies with intervention (ROBINS-I) for N-RCT studies. Meta-analyses were performed to compare primary outcomes and masticatory ability between the occlusal morphologies of artificial teeth of complete or removable partial dentures (α = 0.05). Certainty of the evidence was verified using the GRADE approach.

RESULTS

Eleven studies (seven RCTs and four N-RCTs) were included. The risk of bias was considered low for two studies, some concerns for five, and high for the last four studies. Meta-analyses showed that removable partial dentures with anatomic artificial teeth improved masticatory efficiency for carrot chewing (MD 6.31; 95% CI [3.39, 9.22], I2 = 0%). However, masseter and temporal muscle activities increased when removable partial dentures with nonanatomic teeth were used (MD -756.97; 95% CI [-892.25, -621.68], I2 = 100%). Masticatory ability was not influenced by occlusal morphology during chewing of all foods in complete denture users: Carrot (MD -0.88, 95% CI [-8.98, 7.23], I2 = 57%); sausage (MD -8.86, 95% CI [-23.05, 5.33], I2 = 71%); apple (MD -5.78, 95% CI [-28.82, 17.26], I2 = 87%); and cheese (MD -4.16, 95% CI [-15.14, 6.82], I2 = 62%). The certainty of evidence for all evaluated outcomes was very low, mainly due to very serious problems found in the parameters of inconsistency, indirectness, and imprecision.

CONCLUSIONS

Despite the very low certainty of evidence, the occlusal morphology of artificial teeth influences masticatory function. Anatomic teeth improved the masticatory efficiency and muscle activity of removable partial denture wearers. Nonanatomic teeth increased temporal and masseter muscle activity, which negatively affected chewing in removable partial denture users. However, patients using complete dentures with anatomic and semi-anatomic teeth presented similar masticatory ability.

Four locator attachments of mandibular implant-retained overdentures with two different distributions: A 10-year retrospective preliminary study of residual alveolar ridge changes

OBJECTIVES

There is little information on the long-term function of the four Locator attachment of the mandibular implant retained overdenture (OD), particularly with different distributions.

PURPOSE

To compare the effect of different four inter-foraminal implant distributions retaining a mandibular OD after 10 years of function on posterior mandibular ridge resorption (PMandRR), anterior maxillary ridge resorption (AMaxRR), and the amount of marginal bone loss (MBL) around all four implants.

MATERIALS AND METHODS

Twenty-two participants with total edentulism who had worn mandibular OVDs retained by four inter-foraminal implants for 10 years of functional life were selected for this study. They were divided into two groups based on implant distribution: Group I with a quadrilateral distribution (QD) of implants and Group II with a linear distribution (LD) of implants. PMandRR, AMaxRR, and MBL around implants were measured.

RESULTS

After 10 years of function, PMandRR was significantly higher in the LD group than in the QD group (p < 0.001*). There was no significant difference in AMaxRR between the QD and LD groups (p = 0.431). The QD group showed a significantly greater amount of MBL around dental implants when compared with the LD group (p = 0.002*).

CONCLUSIONS

The LD of implants demonstrates more PMandRR compared with the QD. The QD of implants demonstrates a greater amount of MBL around dental implants compared with the LD. Both implant distributions demonstrate the same effect on the AMaxRR. MBL around implants remained within normal accepted values after 10 years of function.

Effect of dental implant therapy on the preservation of orofacial tissues: A systematic review and meta-analysis

OBJECTIVE

Fundamentally, this review addresses the following question: In partially or fully edentulous patients, do implant-supported dental prostheses preserve orofacial tissues when compared to conventional prostheses or no therapy?

MATERIALS AND METHODS

This study was conducted according to the 2020 PRISMA guidelines for systematic reviews. Electronic searches were conducted at PubMed and Embase databases followed by manual search. Clinical studies comparing the effect of implant-supported prostheses with conventional rehabilitation or no treatment on alveolar bone resorption, remaining teeth, and jaw muscle thickness were considered for inclusion. A qualitative synthesis was conducted with all included studies, and data from selected studies were pooled quantitatively to perform a meta-analysis.

RESULTS

A total of 14 studies were selected for analysis. Six studies reported on the effect of implant therapy on alveolar bone resorption (n = 453), six on the remaining teeth (n = 1014), while four studies evaluated masseter muscle thickness (n = 158). The results of the meta-analyses assessing alveolar bone resorption in the posterior mandible and in the anterior area of the maxilla, both fixed and random effects models, yielded no benefit of rehabilitation with implant-supported prostheses when compared to conventional prostheses. For masseter bone thickness, however, a significant benefit for implant-supported prosthesis was observed.

CONCLUSIONS

This systematic review and meta-analysis were unable to unequivocally answer the focus question. There are some indicators of the benefit of implant-supported prostheses over conventional prostheses or no therapy in preserving orofacial tissues, particularly for masseter muscle thickness. However, the evidence is still insufficient to confirm such perception.

Occlusal Analysis in Natural Dentition: Systematic Review

This study aimed to evaluate the effectiveness of conventional occlusal analysis in contrast with digital occlusal analysis in natural dentition. Occlusal analysis allows the identification of normal and abnormal occlusal contact points that alter the craniomandibular cervical system. We searched for articles with keywords [[dental occlusion]], [[natural dentition]], [[occlusal adjustment]], [[Immediate Complete Anterior Guidance Development]] [[mastication]], [[bite force]], [[premature contact]], [[occlusal balance]] [[articulating paper]]], [[spray]], [[Occlusal contacts]], and [[bite strength]]. They were considered observational , odds ratio and case control studies. We found 189 items. After evaluating the abstracts and full texts of the articles, 10 papers met the inclusion criteria. It was found that occlusal analysis allows the identification of the relationship between poor occlusion and the sensitivity of the teeth due to occlusal trauma, which is also related to temporomandibular joint pain in dynamic occlusion. The contacts of greater strength were observed in nonfunctional cusps, 48%, without ruling out the functional cusps, 24%. Despite being the universal method of occlusal control to date, the use of joint paper, remains subjective compared to the digital occlusal control device. Posture is considered directly related to occlusal trauma and temporomandibular disorders; without proper occlusal analysis, a clear diagnosis of the patient's joint condition cannot be obtained. Digital occlusal analysis is more objective than traditional occlusal analysis.

Quantitative parameters of digital occlusal analysis in dental implant supported restorative reconstruction recent 5 years: a systematic review

OBJECTIVE

The aims of this systematic review were to evaluate the clinical masticatory performance of implant-supported restorations, observe the occlusal force changes in the distribution of the implant restoration and reveal the positive and negative contributing factors of implant design and components based on the outcomes of digital occlusal measurement.

MATERIAL AND METHODS

An extensive search was conducted through PubMed and CENTRAL to identify clinical trials on implant-retained restorations using digital occlusal analysis methods. Two researchers assessed the identified studies and data extraction independently, and the data synthesis strategies without meta-analysis that summarizes the effect estimates were adopted.

RESULTS

The search screened 3821 titles and abstracts, then full-text analysis for 26 articles was performed, and 14 studies were included in the quantitative synthesis. Four of six studies for implant-retained overdenture showed statistically significant improved bite force when immediate loading (p = .00045, .00005, .00055, and .00005, respectively), and no statistically significant results in the other two studies (p = .225, .371, respectively.) However, the results of the favoured intervention were not statistically significant (p = .104, .166, respectively) in two studies of single posterior implant restorations. In all three studies, the bite force distributed on the implant prostheses of partially fixed implant-retained restoration increased statistically significantly (p = .013, .001, .05, respectively).

CONCLUSIONS

The edentulous restoration supported by implants seems to significantly improves bite force and chewing efficiency compared with conventional dentures. Regular quantitative occlusal measurement is recommended to avoid the possible risk of overload. Smaller implants size and relatively small and flexible attachment designs may be more conducive to the stability and retention of the restoration of atrophy of alveolar bone.

Effects of conventional complete dentures and implant-supported overdentures on alveolar ridge height and mandibular bone structure: 2-year and 6-year follow-up study

OBJECTIVES

The aim of this study was to compare the changes in mandibular bone structure in edentulous patients who were rehabilitated with conventional complete dentures (CCD) and implant supported overdentures (ISO), by evaluating alveolar bone loss (ABL), panoramic mandibular index (PMI), mandibular cortical width (MCW), gonion index (GI), antegonial index (AI), and articular eminence inclination (AEI).

MATERIALS AND METHODS

Panoramic radiographs of 63 edentulous patients using CCD, 63 edentulous patients using ISO, and 126 patients without tooth loss were evaluated. Edentulous patients had a 2-year and 6-year follow-up panoramic radiograph image. ABL (anterior, premolar, and molar regions), MCW, PMI, AI, GI, and AEI were measured in each patient. Variation between measurements was analyzed using repeated measures ANOVA test and post hoc Tukey test.

RESULTS

Both edentulous groups showed significantly lower mean than without tooth lost group in all measures (p < 0.000). ISO group showed significantly lower mean ABL than CCD group in anterior (p = 0.000), right premolar (p = 0.005), left premolar (p = 0.005), right molar (p < 0.000), and left premolar (p < 0.000) regions in short term. ISO group showed significantly lower mean ABL than CCD group in anterior (p = 0.021), right molar (p < 0.000), and left premolar (p < 0.000) regions in long-term. There is no statistically significant difference between the CCD and ISO groups in right premolar (p = 0.200) and left premolar (p = 0.134) regions in long term. Both edentulous groups showed significantly lower mean MCW (p < 0.000), PMI (p < 0.000), AI (p < 0.000), GI (p < 0.012), and AEI (p < 0.002) than the without tooth loss group. There is no statistically significant difference between the CCD and ISO groups in terms of changes in the mean MCW, PMI, AI, GI, and AEI measurement in short and long term (p > 0.000).

CONCLUSIONS

In the short and long term, edentulism reduced alveolar crest height, MCW, and AEI in individuals, but had no effect on PMI, AI, or GI. The use of prosthesis did not prevent the decrease of alveolar crest height, MCW, or AEI (CCP or ISO). In the short and long term, however, ISO created less ABL in the mandibular anterior and molar regions than CCD.

CLINICAL RELEVANCE

ABL cannot be halted in edentulous people, but by using ISO instead of CCD for rehabilitation, resorption can be reduced.

Comparison of ridge resorption and patient satisfaction in single implant-supported mandibular overdentures with conventional complete dentures: A randomised pilot study

Purpose

To compare ridge resorption (RR) and patient satisfaction in single implant-supported mandibular overdentures (SIMO) with conventional complete dentures (CCD) over a period of one year.

Material and methods

This prospective, randomized trial enrolled 30 completely edentulous participants following inclusion and exclusion criteria. The study was completed by 28 participants. Rehabilitation of 14 participants was done by using SIMO (group I) and CCD (group C) each according to randomization chart. For both the groups, RR was computed in millimeters from residual ridge height measured by using orthopantogram at 6 months (T1), 9 months (T2), and 12 months (T3) at 3 anatomic locations: maxillary posterior (L1), maxillary anterior (L2), and mandibular posterior (L3). Patient satisfaction was evaluated by using Geriatric Oral Health Assessment Index Hindi version (GOHAI-Hi) at 1week and 12 months after denture delivery.

Results

At 12 months, minimum RR was observed at L2 of group I (0.62 ​± ​0.20 ​mm) and maximum RR was observed at L3 of group C (1.04 ​± ​0.15 ​mm). Comparison of ridge resorption between group I and group C was statistically significant at T3 (P ​= ​.001 for L1, P ​= ​.006 for L2, and P ​= ​.028 for L3). At T3, in group I, RR was more at L3 than L2 region (P ​= ​.011) and L1 region (P ​= ​.015). Statistically significant difference of GOHAI-Hi scores was observed between group I and group C at end of 12 months (P ​= ​.003).

Conclusions

SIMO cause less RR and higher patient satisfaction as compared to CCD and can be recommended with higher predictability of success than CCD.

Computerised occlusal analysis of mini-dental implant-retained mandibular overdentures: A 1-year prospective clinical study

Occlusal analysis is a substantial tool for the functional improvement evaluation after using implant-retained overdenture comparing to complete denture without dental implant retaining. To evaluate occlusal pattern, chewing force distribution in mini-dental implant-retained mandibular overdentures by computerised occlusal analysis system and to compare patient satisfaction after 1-year function. Thirty-one patients wearing complete dentures were included in the study. Prior to mini-dental implant-retained treatment, all patients were assessed for occlusion and force distribution using computerised occlusal analysis system (T-Scan^® ), and then, all patients received two mini-dental implant-retained mandibular overdentures. Mini-dental implants were immediately loaded using low vertical profile attachments (Equator^® ). T-Scan^® was used to evaluate chewing force and force distribution at 1 day, 3 months, 6 months and 12 months. The patient satisfactions before implant placement and after 1 year were evaluated using questionnaires which included satisfaction of denture quality, psychosocial behaviour and chewing efficiency modified from the validated questionnaires. Clinical evaluation of two mini-dental implant-retained mandibular overdentures showed 100% success rate after 1 year. T-Scan^® demonstrated that maximum occlusal contact force increased continuously. The force distribution; the tooth contact number increased over the period. At 1-year follow-up, overall patient satisfaction was significantly greater than before receiving mini-dental implant treatment (P < .001). Using computerised occlusal analysis, mini-dental implants improve complete denture function significantly in terms of maximum occlusal contact force, tooth contact number without the impairment of force distribution. The oral function of the patients has been enhanced.