Intricate Assessment and Evaluation of Effect of Bruxism on Long-term Survival and Failure of Dental Implants: A Comparative Study

Retrospective analysis of dental implant fracture following loading: A retrospective clinical study

STATEMENT OF PROBLEM

Fracture of an osseointegrated implant (FOI) is a rare complication that occurs primarily after loading and may lead to other complications including failure or fracture of the implant-supported prosthesis. Risk factors for FOI are not well understood.

PURPOSE

The purpose of this retrospective clinical study was to determine the frequency of occurrence of FOI among participants treated with dental implants in an academic setting and to identify and analyze the possible risk indicators and contributing factors.

MATERIAL AND METHODS

A retrospective analysis was performed using dental records of participants who received dental implant treatment at the Faculty of Dentistry, University of Toronto, from January 1979 until January 2020, and experienced post-loading FOI. A systematic search of the dental records was conducted, and clinical situations with FOI were identified. Data related to patient factors, implant factors, and prosthesis factors were collected from the identified clinical situations with FOI. The data were analyzed to determine the incidence of FOI. A descriptive analysis was used to identify the possible risk indicators for FOI.

RESULTS

A total of 7712 implants had been placed at the Faculty of Dentistry, University of Toronto, from January 1979 until January 2020. During the 41-year period, a total of 27 fractured implants were identified. The incidence of FOI following loading was 0.35%. Overall, the mean ±standard deviation time between loading and occurrence of implant fracture was 10.6 ±7 years. Implant fractures occurred in 23 different study participants; 16 men, and 7 women, with a mean ±standard deviation age of 65.4 ±8.0 years at the time of FOI. Factors associated with implant fracture include narrow-diameter implants (≤3.75 mm), implants placed in posterior mandible (molar or premolar regions), presence of a long cantilever, and unfavorable implant design (such as the Tri-Channel design). Among the 27 fractured implants, 19 were removed, 6 were buried, and 2 were adjusted or smoothed and restored with a new prosthesis.

CONCLUSIONS

The incidence rate of FOI was very low, but might have been increased by an increased presence of predisposing risk factors.

Dental Implant Failure Risk in Patients with Bruxism-A Systematic Review and Meta-Analysis of the Literature

Background/Objectives: Recent research has indicated that placing dental implants in patients diagnosed with bruxism has led to higher rates of implant failure. This study aimed to provide more accurate knowledge about the relationship between bruxism and implant loss in patients (number, age, gender) with different numbers of implants and prosthetic restorations, considering the follow-up time, compared to non-bruxers. Methods: A systematic search was conducted in PubMed and Cochrane Library using the keyword combination "dental implant", "bruxism", and "implant failure". This search had no language or time restrictions. Results: The review included 15 papers, which were divided into four groups. The first group focused on studies regarding implant loss regardless of the superstructure. In the second group, research on implant-supported removable prostheses was examined. The third group consisted of a single study specifically addressing implant-supported single crowns. Lastly, the fourth group comprised two studies investigating implant-supported single crowns and fixed partial dentures. Only three out of the fifteen studies failed to find a correlation between bruxism and implant failure. The meta-analysis shows a significant pooled effect across the included studies, with an odds ratio of 4.68. Conclusions: Bruxism is a probable risk factor for mechanical issues in implant-supported prostheses and implant-supported crowns. Additionally, elevated failure rates have been documented in patients with bruxism.

Survival of conventional dental implants in the edentulous atrophic maxilla in combination with zygomatic implants: a 20-year retrospective study

PURPOSE

Implant-supported prosthetic rehabilitation in the resorbed maxilla is a great challenge. The aim of this study was to determine the survival rate of conventional anterior implants placed in combination with zygomatic implants according to the Brånemark technique, and to identify risk factors for implant failure.

METHODS

We collected data retrospectively from 72 consecutive patients who received treatment from 1998 to 2018 at our center, according to Brånemark's original technique. Kaplan-Meier analysis was conducted to assess survival rate, and a survival regression model was used with the patient as the random factor, applying the Weibull distribution.

RESULTS

A total of 236 maxillary anterior implants were included, with a mean follow-up of 12.1 years. Kaplan-Meier analysis showed overall cumulative survival rates of 95.3% at 1 year, 94.8% at 2 years, 93.0% at 5 years, 90.5% at 10 years, 81.6% at 15 years, and 67.7% at 20 years. Survival regression showed an association between bruxism and implant failure as well as implants bearing an overdenture. Implants with length ≤ 10 mm had a significantly lower survival time. No significant association was found between the number of anterior implants and survival rate.

CONCLUSIONS

We found acceptable long-term anterior conventional implant survival. Significant risk factors for failure were bruxism, overdentures, and implants shorter than 10 mm.

Risk Factors related to Late Failure of Dental Implant-A Systematic Review of Recent Studies

Resolving late failure of dental implant is difficult and costly; however, only few reviews have addressed the risk factors associated with late failure of dental implant. The aim of this literature review was to summarize the influences of different potential risk factors on the incidence of late dental implant failure. The protocol of this systematic review was prepared and implemented based on the PRISMA (Preferred reporting items for systematic reviews and meta-analyses) guideline. In December 2018, studies published within the previous 10 years on late dental implant failure were selected by fulfilling the eligibility criteria and the risk factors identified in qualified studies were extracted by using a predefined extraction template. Fourteen eligible studies were assessed. The common risk factors for late failure were divided into three groups according to whether they were related to (1) the patient history (radiation therapy, periodontitis, bruxism and early implant failure), (2) clinical parameters (posterior implant location and bone grade 4) or (3) decisions made by the clinician (low initial stability, more than one implant placed during surgery, inflammation at the surgical site during the first year or using an overdenture with conus-type connection). Clinicians should be cautions throughout the treatment process of dental implant-from the initial examination to the treatment planning, surgical operation and prosthesis selection-in order to minimize the risk of late failure of dental implant.

Incidence of Prosthetic Complications associated with Implant-borne Prosthesis in a Sleep Disorder Center

BACKGROUND

Obstructive sleep apnea (OSA) is one of the common prevalent conditions present worldwide. The process of abnormal habits related to clenching and grinding of teeth is referred to as bruxism and is characterized under the heading of parafunctional activity of the masticatory system. Osseointegrated dental implants represent advancements in the field of odontology. Despite its high success rate, failure and complications are often associated with dental implant treatment due to a number of factors. Hence, we aimed for the present study to assess the incidence of prosthetic complications in patients rehabilitated with implant-borne prosthesis in a sleep disorder unit.

MATERIALS AND METHODS

The present study included the assessment of all the patients who underwent prosthetic rehabilitation by dental implants. An experienced registered prosthodontist was given duty for examination of all the cases from the record file data. Prosthetic complications in the patients were identified using photographs, radiographs, and all other relevant data of the patients obtained from the record files. All types of complications and other factors were recorded separately and analyzed.

RESULTS

While correlating the prosthetic complications in OSA patients grouped based on number of dental implants, nonsignificant results were obtained. Significant correlation was observed while comparing the prosthetic complications divided based on type of prosthesis. Fracture of the porcelain was observed in four and eight cases respectively, of screwed and cemented dental implant cases.

CONCLUSION

Some amount of significant correlation existed between the incidences of prosthetic complications and OSA.

CLINICAL SIGNIFICANCE

Proper history of the patients undergoing dental implant procedures should be taken to avoid failure.

Dental Implants Placed in Patients with Mechanical Risk Factors: A Long-term Follow-up Retrospective Study

Objectives:

Risk factors in oral implantology are defined as local or systemic conditions that increase failure rates. The purpose of this paper is to evaluate the long-term survival rate of dental implants placed in patients presenting mechanical risk factors.

Materials and Methods:

This retrospective study was conducted only with patients presenting at least one of the following risk factors were included: Bruxism; crown-to-implant (C/I) ratio <0.8; abutment angulation. The overall implant survival was estimated using Kaplan–Meier analyses. Risk factors for implant failure were identified using the Cox proportional hazard regression models.

Results:

Eighty-nine eligible patients were enrolled in this study: They were both male (n = 56, 62.92%) and female (n = 33, 37.08%), with an average age of 53.24 (23–76 years), with 227 dental implants inserted. The mean follow-up was 13.6 years (range: 10–16 years). The overall 10-year Kaplan–Meier survival estimate with associated 95% confidence intervals was 86.34% (82.8, 87.1). Bruxism was the only variable that showed a statistically significant association with implant failure (P < 0.05) and a hazard ratio of 2.9, while both Crown to-implant and abutment angulations reported lower values of failure (P > 0.05).

Conclusions:

Within the limitations of this study, can be concluded that data suggested an evident relationship between bruxism and dental implant failure but further studies, with a larger sample and a different design are required to assess this relationship.

Tardive Dyskinesia, Oral Parafunction, and Implant-Supported Rehabilitation

Oral movement disorders may lead to prosthesis and implant failure due to excessive loading. We report on an edentulous patient suffering from drug-induced tardive dyskinesia (TD) and oral parafunction (OP) rehabilitated with implant-supported screw-retained prostheses. The frequency and intensity of the movements were high, and no pharmacological intervention was possible. Moreover, the patient refused night-time splint therapy. A series of implant and prosthetic failures were experienced. Implant failures were all in the maxilla and stopped when a rigid titanium structure was placed to connect implants. Ad hoc designed studies are desirable to elucidate the mutual influence between oral movement disorders and implant-supported rehabilitation.