The intra- and inter-rater reproducibility of bone level measurements at strategic mini-implants using dental panoramic radiography.

OBJECTIVES: This experimental study focused on the intra- and inter-rater reproducibility of vertical bone level (VBL) measurements at strategic mini-implants (MI) using digital panoramic radiographs (PR). STUDY DESIGN: VBLs of 152 MIs for removable partial denture stabilization at 50 randomly chosen PRs from a clinical trial were digitally evaluated by three ratters. Rater deviations exceeding 0.5 mm were re-examined. The intra-class correlation coefficient (ICC) was applied to estimate reliability. The smallest detectable change (SDC) was interrelated to the minimal clinically important change of 0.2 mm. RESULTS: The first measurement round revealed intra- and inter-rater ICCs of > 0.8. However, 28 sites (9 %) were unreadable, and 97 sites (32 %) revealed differences between observers of ≥ 0.5 mm. Following a consensus session and re-training, an additional 8 sites were excluded and all remaining VBL differences were ≤ 0.5 mm. Thus, the SDCs with 95 % credibility were improved from 0.73 to 0.31 mm in the intra-rater and from 1.52 to 0.34 mm in the inter-rater statistics. Given a 50 % credibility for this special setting, both the intra- and inter-rater SDCs were 0.11 mm. CONCLUSIONS: Digital PR can be reliably utilized to determine VBLs around MIs under conditions of at least two trained observers, mutual calibration sessions, and exclusion of unquantifiable radiographs. GERMAN CLINICAL TRIALS REGISTER ID: DRKS00007589, www.germanctr.de.

The intra- and inter-rater reproducibility of bone level measurements at strategic mini-implants using dental panoramic radiography

Abstract Objectives: This experimental study focused on the intra- and inter-rater reproducibility of vertical bone level (VBL) measurements at strategic mini-implants (MI) using digital panoramic radiographs (PR). Study design: VBLs of 152 MIs for removable partial denture stabilization at 50 randomly chosen PRs from a clinical trial were digitally evaluated by three ratters. Rater deviations exceeding 0.5 mm were re-examined. The intra-class correlation coefficient (ICC) was applied to estimate reliability. The smallest detectable change (SDC) was interrelated to the minimal clinically important change of 0.2 mm. Results: The first measurement round revealed intra- and inter-rater ICCs of > 0.8. However, 28 sites (9 %) were unreadable, and 97 sites (32 %) revealed differences between observers of ≥ 0.5 mm. Following a consensus session and re-training, an additional 8 sites were excluded and all remaining VBL differences were ≤ 0.5 mm. Thus, the SDCs with 95 % credibility were improved from 0.73 to 0.31 mm in the intra-rater and from 1.52 to 0.34 mm in the interrater statistics. Given a 50 % credibility for this special setting, both the intra- and inter-rater SDCs were 0.11 mm. Conclusions: Digital PR can be reliably utilized to determine VBLs around MIs under conditions of at least two trained observers, mutual calibration sessions, and exclusion of unquantifiable radiographs. German Clinical Trials Register ID:DRKS00007589, www.germanctr.de

HOW TO IDENTIFY SUBGROUPS IN LONGITUDINAL CLINICAL DATA: TREATMENT RESPONSE PATTERNS IN PATIENTS WITH A SHORTENED DENTAL ARCH.

BACKGROUND: When dental patients seek care, treatments are not always successful,that is patients' oral health problems are not always eliminated or substantially reduced. Identifying these patients (treatment non-responders) is essential for clinical decision-making. Group-based trajectory modeling (GBTM) is rarely used in dentistry, but a promising statistical technique to identify non-responders in particular and clinical distinct patient groups in general in longitudinal data sets. AIM: Using group-based trajectory modeling, this study aimed to demonstrate how to identify oral health-related quality of life (OHRQoL) treatment response patterns by the example of patients with a shortened dental arch (SDA). METHODS: This paper is a secondary data analysis of a randomized controlled clinical trial. In this trial SDA patients received partial removable dental prostheses replacing missing teeth up to the first molars (N = 79) either or the dental arch ended with the second premolar that was present or replaced by a cantilever fixed dental prosthesis (N = 71). Up to ten follow-up examinations (1-2, 6, 12, 24, 36, 48, 60, 96, 120, and 180 months post-treatment) continued for 15 years. The outcome OHRQoL was assessed with the 49-item Oral Health Impact Profile (OHIP). Exploratory GBTM was performed to identify treatment response patterns. RESULTS: Two response patterns could be identified - "responders" and "non-responders." Responders' OHRQoL improved substantially and stayed primarily stable over the 15 years. Non-responders' OHRQoL did not improve considerably over time or worsened. While the SDA treatments were not related to the 2 response patterns, higher levels of functional, pain-related, psychological impairment in particular, and severely impaired OHRQoL in general predicted a non-responding OHRQoL pattern after treatment. Supplementary, a 3 pattern approach has been evaluated. CONCLUSIONS: Clustering patients according to certain longitudinal characteristics after treatment is generally important, but specifically identifying treatment in non-responders is central. With the increasing availability of OHRQoL data in clinical research and regular patient care, GBTM has become a powerful tool to investigate which dental treatment works for which patients.

Survival and stability of strategic mini-implants with immediate or delayed loading under removable partial dentures: a 3-year randomized controlled clinical trial.

OBJECTIVES: Stability values of mini-implants (MIs) are ambiguous. Survival data for MIs as supplementary abutments in reduced dentitions are not available. The aim of this explorative research was to estimate the 3-year stability and survival of strategic MIs after immediate and delayed loading by existing removable partial dentures (RPDs). MATERIAL AND METHODS: In a university and three dental practices, patients with unfavorable tooth distributions received supplementary MIs with diameters of 1.8, 2.1, and 2.4 mm. The participants were randomly allocated to group A (if the insertion torque ≥ 35 Ncm: immediate loading by housings; otherwise, immediate loading by RPD soft relining was performed) or delayed loading group B. Periotest values (PTVs) and resonance frequency analysis (RFA) values were longitudinally compared using mixed models. RESULTS: A total of 112 maxillary and 120 mandibular MIs were placed under 79 RPDs (31 maxillae). The 1st and 3rd quartile of the PTVs ranged between 1.7 and 7.8, and the RFA values ranged between 30 and 46 with nonrelevant group differences. The 3-year survival rates were 92% in group A versus 95% in group B and 99% in the mandible (one failure) versus 87% in the maxilla (eleven failures among four participants). CONCLUSIONS: Within the limitations of explorative analyses, there were no relevant differences between immediate and delayed loading regarding survival or stability of strategic MIs. CLINICAL RELEVANCE: The stability values for MIs are lower than for conventional implants. The MI failure rate in the maxilla is higher than in the mandible with cluster failure participants. CLINICAL TRIAL REGISTRATION: German Clinical Trials Register (Deutsches Register Klinischer Studien, DRKS-ID: DRKS00007589, www.germanctr.de ), January 15, 2015.

Upgrading removable denture design by using strategic implants: A case report.

Inserting a dental implant in a strategic position under a removable partial denture (RPD) can upgrade the RPD design by changing a mainly tissue-supported RPD to an implant-tissue-supported RPD or an implant-tooth-tissue-supported RPD with better retention, support, and stability. CASE PRESENTATION: The patient (female, 77-year-old) was unsatisfied with her maxillary and mandibular clasp-retained removable dentures (RDs). Medical, social, and systemic health evaluations revealed that the patient was healthy. Dental history, intraoral and extraoral examinations, functional screening, and esthetic analyses revealed that the patient had a reduced vertical dimension, resulting in pseudo-class III malocclusion and angular cheilitis. Strategic implants were used to improve the retention, support, and stability of the new RDs. The maxillary canine 23 (World Dental Federation notation) and maxillary premolar 24 were used to retain the maxillary conical crown attachments. Three strategic mini-implants were inserted in the positions of teeth 12, 13, and 14 to support and retain the maxillary RPD. Two locators above the standard implants (33 and 43) were used to support and retain the mandibular overdenture. An improvement in the oral health-related quality of life and patient satisfaction with respect to the maxillary and mandibular RDs was observed immediately after using the new RDs. This improvement did not diminish after a year. CONCLUSION: Herein, using strategic implants to support the maxillary RPD and two standard implants under the mandibular overdenture improved the oral health-related quality of life and patient satisfaction with respect to the maxillary and mandibular prostheses in terms of the retention, stability, support, eating ability, speaking ability, appearance, and cleanability.

IMPACT OF SHORTENED DENTAL ARCH ON ORAL HEALTH-RELATED QUALITY OF LIFE.

BACKGROUND: A shortened dental arch (SDA) is an established treatment concept for patients with missing molars. However, little is known regarding long-term course of oral health-related quality of life (OHRQoL) in patients with SDA and the benefits from replacement of missing molars. OBJECTIVE: Purpose of this multi-center randomized clinical trial was to assess OHRQoL over a period of 15 years in patients with molar replacement by a removable partial denture (RPD) compared to patients with a restored SDA without molar replacement. METHODS: Patients at least 35 years of age with all molars missing in 1 jaw and at least the canine and one premolar present on each side were included. Patients received either a precision attachment-retained, RPD for replacement of missing molars (n = 79), or the dental arch ended with the second premolar (SDA) that had to be present or replaced by a cantilever fixed dental prosthesis (n = 71). Follow-up examinations continued for 15 years. OHRQoL was assessed with the 49-item Oral Health Impact Profile (OHIP). OHIP summary and dimension scores were longitudinally modeled in the statistical analyses to assess course of OHRQoL over time applying an intention-to-treat approach. In addition, scores for the OHRQoL dimensions Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact were analyzed. RESULTS: After an initial improvement in OHRQoL indicated by a mean decrease of 20.0 OHIP points with an effect size of 0.61 in the entire study population, OHRQoL stayed relatively constant over the entire follow-up period. Assuming a constant time and treatment effects over the study period, OHRQoL did not differ statistically significant between the 2 treatments (0.4 OHIP points; 95%-CI: 7.1 - 6.2). OHRQoL after treatment did not change notably over 15 years and was statistically nonsignificant as well (P = .872). Similar findings were observed in all 4 OHRQoL dimensions. CONCLUSIONS: In patients, missing all molars in one jaw OHRQoL improved providing RPD or restoring SDA to a clinically relevant degree. Treatment-related improvement remained mostly stable over a period of at least 15 years. Therefore, patients can be informed that both treatment concepts are equivalent concerning long-term OHRQoL. Accordingly, patients' preferences regarding treatment options should be granted priority in treatment decision making with the SDA treatment option being the default.

Validity and reliability of new instruments for measuring patient satisfaction with removable dentures, Arabic Version.

BACKGROUND: The psychometric properties of self-administered instruments for measuring patient satisfaction with removable dentures should be tested before inviting patients to express their opinions. This study aimed to evaluate the validity and reliability of new instruments in the Arabic language that measure patient satisfaction with all types of removable dentures. METHODS: A three-step methodology was used to translate and test the instruments. In step one, the instruments were translated from tested German instruments to develop the pilot questionnaires. In step two, the face validity of the pilot questionnaires was tested through three rounds of interviews. There were 15, 13, and 15 participants per round, respectively. At the end of every round, the results of the interviews were discussed with an expert panel. The expert panel confirmed the form and the type of questionnaires' adjustments before a new round of interviews began. At the end of step two, the final form of the questionnaires was reached. In step three, 235 questionnaires were distributed to 133 participants to estimate the construct validity of the upper jaw and the lower jaw questionnaires. After one week, the participants were asked to complete the questionnaires again. A total of 102 questionnaires were returned and used to assess the instruments' reliability. Factor analysis was used to assess the construct validity. The intraclass correlation coefficient and Cronbach's alpha were used to estimate the reliability and suitability of the items in the indexes. RESULTS: The result of step one was two pilot questionnaires. The pilot questionnaires were adjusted in step two. At the end of step two, the questionnaires proved to have good face validity. Factor analyses in step three revealed that only one factor could be retained. The one-factor model explained 60.95% and 63.06 of the total variance of the upper jaw and lower jaw questionnaires, respectively. The items in every questionnaire shared the same cluster and could be summed to form an upper jaw index and lower jaw index that reflected patient satisfaction with removable dentures. Cronbach's alpha values indicated excellent internal consistency and reliability for the upper jaw questionnaire (α = 0.91) and the lower jaw questionnaire (α = 0.92). Intraclass correlation coefficient values ranged from 0.72 to 0.95, which can be considered "moderate" to "excellent". CONCLUSIONS: The Arabic version of questionnaires and indexes assessing patient satisfaction with upper and lower removable dentures are reliable and valid self-administered instruments.

Rehabilitation of shortened dental arches: A fifteen-year randomised trial.

BACKGROUND: Few long-term studies on treatments in the shortened dental arch (SDA) are available. OBJECTIVE: The objective of this trial was to analyse the long-term success of two different treatment concepts. METHODS: Patients over 35 years of age with missing molars in one jaw and at least the canine and one premolar present on both sides were eligible. In the partial removable dental prosthesis (PRDP) group (N = 81), molars and missing second premolars were replaced by a precision attachment retained prosthesis. In the SDA group (N = 71), the dental arch ended with the second premolar that had to be present or replaced by a cantilever fixed dental prosthesis. Follow-up examinations were carried out over 15 years. RESULTS: A comprehensive outcome variable comprised four failure categories for which Kaplan-Meier survival (success) analyses were conducted. Half of the patients exhibited a continuous preservation of the per protocol prosthetic status that remained totally unaffected by complications for more than 10 years. The event-free success rates for moderate or worse failure implied a loss of the per protocol prosthetic status. The respective survival rates fell below 50% at 14.2 years in the PRDP group and 14.3 years in the SDA group. In none of the analyses, a significant group difference was found. CONCLUSIONS: In patients with an SDA condition, changes in the prosthetic status have to be expected. The affected proportion increases almost linearly from shortly after treatment and comprises the majority after 15 years. The influence of the examined treatments on success appears to be low.

Randomized trial in split-mouth design to evaluate the effectiveness of manual and machine-aided cleaning of removable partial dentures.

PURPOSE: To evaluate the efficacy of manual and machine-aided cleaning to remove matured plaque from removable partial dentures (RPD). MATERIALS AND METHODS: A total of 32 patients with bilateral free-end saddle RPDs were included. The plaque was stained, and the RPD was photographed on all sides. One saddle was randomly allocated to manual cleaning, while the other was allocated to no cleaning. The patient manually cleaned the saddle by applying a denture brush and gel. The whole RPD was then cleaned with the aide of a machine using a rotating needle device. After each step, plaque dyeing and photographing were repeated. The plaque proportions (% pixel) were measured using special software. For statistical analysis, mixed models were used to adjust for baseline covariates, including plaque and surfaces, and to cover all time points. RESULTS: The mean plaque area without cleaning at the fitting surface was higher than at the buccal/lingual surfaces (32.8% [95% CI: 28.1% to 36.4%] vs 15.3% [13.1% to 17.4%], respectively). Manual cleaning was not substantially better than no cleaning (4.6% [-0.1% to 9.2%] for the difference at fitting surfaces; disclaiming a substantial difference of > 10%; the difference found was even smaller at buccal/lingual surfaces). Machine-aided cleaning was substantially better than manual cleaning (16.1% [12.0% to 20.2%] for the difference at fitting surfaces and 7.3% [4.6% to 10.0%] at buccal/lingual surfaces). The combination of manual and machine-aided cleaning was not better than machine-aided cleaning alone (-0.2% [-2.6% to 2.1%] difference at fitting surface). CONCLUSION: Manual cleaning is insufficient in removing matured denture plaque. Machine-aided cleaning is clearly superior to manual cleaning, especially at fitting surfaces.

Immediate versus delayed loading of strategic mini-implants under existing removable partial dentures: patient satisfaction in a multi-center randomized clinical trial.

OBJECTIVE: The purpose of this study was to evaluate and compare the effects of the immediate and delayed loading of strategic mini-implants (MIs) on the satisfaction of patients with removable partial dentures (RPDs). MATERIALS AND METHODS: In this multi-center randomized clinical trial, strategic MIs were inserted under 79 RPDs in 76 participants. Two questionnaires, one for the upper jaw and one for the lower jaw, were given before surgical intervention and 2 weeks, 4 months, 4.5 months, 1 year, 2 years, and 3 years after implant insertion. To estimate the loading effect (immediate vs. delayed) in terms of the odds ratio, an ordinal logistic regression model was used. The Wilcoxon matched-pairs signed-rank test, which was corrected for clusters in the patient population, was used to evaluate changes in patient satisfaction. RESULTS: After 4 months, a statistically significant difference in favor of the immediate loading group was recognized in terms of the overall satisfaction score. The patient satisfaction scores recorded after 4.5 months and 1, 2, and 3 years showed substantial improvements compared with the scores recorded before implant insertion in both groups. At the item level, substantial improvements were noted in the following domains: general satisfaction, RPD retention, stability, support, eating, speaking, and aesthetics. CONCLUSIONS: Strategic MIs improved the satisfaction of patients with RPDs during the medium-term follow-up period. An earlier improvement in the satisfaction of patients with RPDs was seen after immediate loading of the MIs as compared with delayed loading. CLINICAL RELEVANCE: Inserting MIs under existing RPDs can improve patients' satisfaction with their RPDs in several domains.

SHIP-MR and Radiology: 12 Years of Whole-Body Magnetic Resonance Imaging in a Single Center.

The Study of Health in Pomerania (SHIP), a population-based study from a rural state in northeastern Germany with a relatively poor life expectancy, supplemented its comprehensive examination program in 2008 with whole-body MR imaging at 1.5 T (SHIP-MR). We reviewed more than 100 publications that used the SHIP-MR data and analyzed which sequences already produced fruitful scientific outputs and which manuscripts have been referenced frequently. Upon reviewing the publications about imaging sequences, those that used T1-weighted structured imaging of the brain and a gradient-echo sequence for R2* mapping obtained the highest scientific output; regarding specific body parts examined, most scientific publications focused on MR sequences involving the brain and the (upper) abdomen. We conclude that population-based MR imaging in cohort studies should define more precise goals when allocating imaging time. In addition, quality control measures might include recording the number and impact of published work, preferably on a bi-annual basis and starting 2 years after initiation of the study. Structured teaching courses may enhance the desired output in areas that appear underrepresented.

The lingual foramina, a potential risk in oral surgery. A retrospective analysis of location and anatomic variability.

OBJECTIVE: This study evaluates the mandibular lingual foramina (LF) using computed tomographic imaging data from a large Central European cohort, focusing on the most relevant anatomical parameters. We aimed to examine whether there are differences in key parameters between ethnic groups, or based on age and gender. Additionally, we analyze the potential effect of tooth loss on the LF and discuss risk management options before and during surgery. METHODS: 460 CT scans of adults (273 females and 186 males) were examined. The number, the location and the diameter of the median and lateral LF were assessed for each patient. The data was analyzed statistically, whereby a p-value lower than 0.05 was considered as significant. RESULTS: Median and lateral LF were present in 95,9%, and 38,9% of patients, respectively. Male patients had a greater number of LF than females. While the majority of median LF (62%) was located above the mental spine, the majority of lateral LF was located below (84%). The diameter of lateral LF (1,15 mm ± 0,33) was smaller than for median LF (1,22 mm ± 0,35), as well the lateral canals (4,8 mm ± 1,28) were shorter than the median canals (5,32 mm ± 1,74). Lateral LF were equidistant to the symphysis (13,89 ± 3,63 mm) on either side. Critical diameter size >1 mm was found in about 2/3 of our cases. The distance from the foramen to the residual ridge was ∼7 mm less in edentulous patients compared to dentulous patients. CONCLUSION: The median LF is a near-obligatory structure of the mandible, while the lateral LF is a frequently encountered structure. Age does not seem to affect the frequency of LF. Edentulous patients did not show differences regarding the presence of the LF, but their vertical osseous dimension was diminished by 7 mm and they may, therefore, be at an increased risk of adverse surgical incidents. The main findings of this study relate to the substantial variability in the anatomy and location of the LF and confirm with previous studies. As the LF can be reliably detected using CT/CBCT, the use of three-dimensional-imaging is recommended prior to conducting oral surgery. Careful pre-operative planning and accurate anatomical information may help to avoid surgical complications. To ascertain the potential significance of ethnicity on LF, more data need to be collected using standardized methodologies. A definitive conclusion on the impact of ethnicity on LF thus cannot currently be drawn based on the results of our study and those available from the published medical literature.

Periodontal health in shortened dental arches: A 10-year RCT.

PURPOSE: This analysis focused on periodontal health in shortened dental arches (SDAs). METHODS: In a randomized controlled clinical trial, patients with missing molars in one jaw and at least one premolar and canine on both sides were eligible for participation. In the partial removable dental prosthesis (PRDP) group (n = 79), molars were replaced with a precision attachment retained PRDP. In the SDA group (n == 71), the SDA up to the second premolars was either left as is or restored with fixed dental prostheses. Outcome variables were vertical clinical attachment loss (CAL-V), pocket probing depth (PPD), bleeding on probing (BOP) and plaque index (PLI). For CAL-V and PPD, the changes at six measuring points per tooth were analyzed. For BOP and PLI, patient related rates were calculated for each point in time. Statistical methods included linear regression analyses. RESULTS: In the intention-to-treat (ITT) analysis for CAL-V in the study jaw, the 10 year patient related mean changes were 0.66 mm in the PRDP group and -0.13 mm in the SDA group. The resulting mean patient related group difference of 0.79 mm (95% CI: 0.20 mm-1.38 mm) was significant (p = 0.01). There were no significant differences in the ITT analyses for PPD. For BOP and PLI, significant group differences with more favorable results for the SDA group were found. CONCLUSIONS: In view of lacking substantial differences for CAL-V and PPD, the overall differences were considered of minor clinical relevance. The results add confirmatory evidence to the shortened dental arch concept and its clinical viability (controlled-trials.com ISRCTN97265367).

Stabilizing Removable Partial Dentures by Immediate or Delayed Loading of Mini-implants: Chewing Efficiency in a Randomized Controlled Clinical Trial.

PURPOSE: The aim of this investigation was to compare the chewing efficiency after immediate and delayed loading of mini-implants that served as supplementary support for removable partial dentures (RPDs). MATERIALS AND METHODS: In this four-center randomized trial, patients who had RPDs in arches with unfavorable tooth distributions, ie, no canine and at most two posterior teeth in one or both quadrants, received strategic mini-implants with ball abutments. The mini-implants in group A were loaded immediately either by housings with O-rings (insertion torque ≥ 35 Ncm) or by soft relining material (insertion torque < 35 Ncm). In group B, the RPDs were only hollowed over the balls. After 4 months, the soft relined RPDs and all RPDs of group B received the housings. Masticatory efficiency was evaluated with a validated mixing ability test of two-colored chewing gum before surgery and 14 days, 4 months (before housing pickup), 4.5 months, and 12 months after surgery. The circular variance of hue was the measure of mixing. RESULTS: From 76 participants with 79 RPDs, 38 each were randomly allocated to group A or B. In group A, the housings in six participants were picked up immediately, and the remaining RPDs were primarily soft relined. There was a significant group difference only after 4 months. The mixing ability was better after immediate loading than after delayed loading (P < .0001). In group B, the chewing efficiency was notably deteriorated after the RPDs were hollowed over the ball abutments. However, immediately after all housings were picked up, the chewing efficiency in both groups was substantially improved, and the variance of hue values after 1 year were very similar in the groups. CONCLUSION: The chewing performance can be improved by inserting supplementary mini-implants under existing RPDs with unfavorable tooth support. This improvement occurred faster by immediate loading than by delayed loading.

Stabilizing mandibular complete dentures by a single midline implant-influence on quality of life: 2-year results from a randomized clinical trial comparing different loading protocols.

OBJECTIVES: The knowledge about the influence of dental treatment on health-related quality of life (HRQoL) is still limited. The aim of this multicenter randomized controlled clinical trial was to assess the effect of stabilizing an existing complete denture, by means of a single mandibular implant, on HRQoL. Furthermore, the impact of the loading protocol, i.e., immediate or delayed loading, in edentulous patients was evaluated. METHODS: One hundred fifty-eight participants aged 60-89 years were randomly assigned to study group A (immediate loading; n = 81) and to group B (delayed loading; n = 78). All participants received a single midline implant in the mandible. The implants were either immediately loaded (group A) or after a closed healing period of 3 months (group B) by connecting the existing mandibular complete dentures to ball attachments. HRQoL was assessed with the Short Form-36 questionnaire of health (SF-36) at baseline, 4 months, and 24 months after implant loading. RESULTS: Improvement of HRQoL by means of a single implant-retained mandibular overdenture could not be demonstrated after 4 and 24 months of implant loading. Furthermore, the application of two different loading protocols did not influence HRQoL ratings of study participants. CONCLUSION: The loading protocol is not a factor, influencing HRQoL in patients treated by a single midline implant in the edentulous mandible. CLINICAL RELEVANCE: A single midline implant in the edentulous mandible, stabilizing a mandibular complete denture, cannot be recommended for improving HRQoL.

Impact of shortened dental arch on oral health-related quality of life over a period of 10 years - A randomized controlled trial.

OBJECTIVES: To compare oral health-related quality of life (OHRQoL) in patients with either molar replacement by partial removable dental prostheses (PRDP) or with restored shortened dental arches (SDA) over a period of 10 years. METHODS: In this multi-center RCT, a consecutive sample of 215 patients with bilateral molar loss in at least one jaw was initially recruited in 14 prosthodontic departments. Of those patients, 150 could be randomly allocated to the treatment groups (SDA: n = 71; PRDP: n = 79), received the allocated treatment, and were available for follow-up assessments. OHRQoL was assessed using the 49-item version of the Oral Health Impact Profile (OHIP) before treatment (baseline) and at follow-ups after treatment (4-8 weeks and 6, 12, 24, 36, 48, 60, 96, and 120 months). To investigate the course of OHRQoL over time, we longitudinally modelled treatment and time effects using mixed-effects models. RESULTS: OHRQoL substantially improved from baseline to first follow-up in both groups indicated by a mean decrease in OHIP scores of 20.0 points (95%-CI: 12.5-27.5). When compared to the SDA group, OHRQoL in the PRDP group was not significantly different (-0.6 OHIP points; 95%-CI: -7.1 to 5.9) during the study period when assuming a constant time effect. OHRQoL remained stable over the 10 years with a statistically insignificant time effect (p = 0.848). CONCLUSIONS: For patients requesting prosthodontic treatment for their lost molars, treatments with SDA or PRDP improve clinically relevantly OHRQoL and maintain it over a period of 10 years with no option being superior to the other. CLINICAL SIGNIFICANCE: Since there was no significant difference between the two treatment options over the observation period of 10 years, and since results have stayed stable over time, patients can be informed that both treatment concepts are equivalent concerning OHRQoL.

Reducing uncertainty in estimating associations of oral exposures with Helicobacter pylori serology in the general population.

AIM: Evidence for reducing Helicobacter (H.) pylori by periodontal therapy comes from small studies in China, limiting generalizability. To estimate the association between periodontal disease and anti-H. pylori IgG titer levels in a European country, we used population-based data from the Study of Health in Pomerania. MATERIALS AND METHODS: For pocket depth as the primary exposure, we restricted the age range to participants younger than 60 years (n = 2,481) to avoid selection bias due to edentulism in this cross-sectional study. For the full age range up to 81 years, we chose the number of missing teeth (n = 3,705). RESULTS: The association between pocket depth and the outcome was weak. Given the ceiling effect for the number of missing teeth (ordinal logistic regression; odds ratio of the interquartile range effect = 1.6; 95% CI: 1.3-1.9; p-value for linearity = 0.005), we checked whether wearing removable dental prosthesis was associated with higher anti-H. pylori IgG titer levels (odds ratio = 1.3; 95% CI: 1.1-1.5). CONCLUSIONS: Tooth loss and wearing removable dental prosthesis were weakly to moderately associated with higher anti-H. pylori IgG titer levels in the general population of a European country.

Prosthetic Tooth Replacement in a German Population Over the Course of 11 Years: Results of the Study of Health in Pomerania.

PURPOSE: To evaluate changes in distribution of teeth and in prosthodontic tooth replacement during an 11-year period in an adult population. MATERIALS AND METHODS: Information on prosthetic status was collected from 4,288 participants aged 20 to 81 years at baseline in the Study of Health in Pomerania (SHIP-0) and from 2,244 participants aged 30 to 92 years who reappeared in the 11-year follow-up (SHIP-2). The tooth distribution per arch was classified into one of the six following classes: class 0 (edentulous), class 1 (one to three remaining teeth), class 2 (extended tooth-bounded space or extreme shortened dental arch), class 3 (small anterior space), class 4 (small posterior space with one or more missing premolars), or class 5 (functional dentition). RESULTS: Longitudinally, the most pronounced change in class was the transition from class 1 to class 0 (maxilla: 54.5%, mandible: 58.3%). The percent change from other higher classes to lower classes ranged between 10% and 40%. In the same age groups of 40 to 79 years, the number of edentate arches was cut in half, with a corresponding increase in functional dentitions. The proportion of unrestored arches decreased in all classes. Double crown-retained partial removable dental prostheses (PRDPs) showed the highest increase (a 15% to 20% increase) at the expense of acrylic PRDPs in classes 1 and 2. In small spaces, the proportion of fixed dental prostheses (FDPs) also increased by 15% to 20%. Seven participants of SHIP-0 (0.16%) and 56 participants of SHIP-2 (2.5%) had dental implants. CONCLUSION: Similar age groups showed improvement in oral conditions. The proportion of higher-end restorations (FDPs and double crown-retained PRDPs), including the frequency of dental implants, increased.

Applicability of Computerized Planimetric Method in Estimating Plaque Accumulation and Efficacy of a Cleaning Method for Removable Dental Prostheses.

PURPOSE: To demonstrate how data collected using the computerized planimetric method (CPM) can be analyzed by providing an example in which the amount of plaque accumulation and the efficacy of the rotating needles device (RND) in cleaning specific parts of partial removable dental prostheses (PRDPs) were estimated. MATERIALS AND METHODS: Thirty-four participants wearing a total of 41 double-crown-retained PRDPs with veneered secondary crowns were included in this study. The PRDPs underwent the following steps: preparing the PRDP for photography, photography of the PRDP, cleaning the PRDP with the RND, and re-photography. One trained examiner used a tested CPM to analyze 98 images (49 before/49 after). Each participant was considered as a statistical unit; thus, if the participant had two PRDPs, one was randomly selected for analysis. Reliability was tested using intraclass correlation coefficients (ICCs[1, 2]), and nonparametric Wilcoxon signed rank test was used for all comparisons. RESULTS: The intraclass correlation coefficients (images before/after) for both the base and veneer were > 0.9. Wilcoxon signed rank test P value was < .001 for the comparison of plaque accumulation on the base and veneer, estimating the RND's efficacy on both PRDP parts (before/after) and comparing the RND's efficacy on the base and the RND's efficacy on the veneer. CONCLUSIONS: There are different ways to analyze data collected via CPM; thus, it is advisable to provide an explanation for the choice of modeling. Plaque accumulation was significantly greater on the double-crown veneer than on the base. The RND efficacy in cleaning the veneer and the base is significant, but more substantial in cleaning the base.

The single mandibular implant study - Short-term effects of the loading protocol on Oral Health-related Quality of Life.

PURPOSE: A single implant can be placed to retain an overdenture in the edentulous mandible. This study aimed at the development of Oral Health-related Quality of Life comparing immediate and delayed implant loading, i.e., loading after 3 months of submerged healing. METHODS: In a randomized controlled trial, 158 participants received a single mandibular implant in the midline. Quality of life was measured using the summary score of the German 49-item Oral Health Impact Profile at baseline, one month after implant placement (direct loading group) as well as one and four months after loading. RESULTS: Mean scores at baseline were comparable. Four months after implantation, a decrease of mean scores was recognized for both groups, indicating a significantly enhanced quality of life after treatment. When comparing the groups after both 1 and 4 months of loading, quality of life was insignificantly higher in the delayed loading group (1 month: 42.1 vs. 32.3; 4 months: 33.6 vs. 27.7). For immediate loading, an insignificant tendency to an earlier improvement was recognized (Δ1month-baseline: 9.7, compared to Δ1month-baseline: 6.4). CONCLUSIONS: The single mandibular implant concept was associated with a positive impact on quality of life. However, no statistically significant influence of implant loading on quality of life was found.