Marginal bone loss of two implant systems with three different superstructure materials: a randomised clinical trial

Marginal bone level is a criterion for implant success. The aetiological factors of bone loss have not been clarified. The aim of this study was to evaluate the influence of implant systems and prosthetic materials on the marginal bone loss. Twenty‐three patients participated; two implant systems and three superstructure materials were used in this study. Twenty‐two of the implants were restored with porcelain fused to base metal alloy (BMA), 25 with porcelain fused to noble metal alloy (NMA) and 20 with zirconium oxide‐based ceramics. Radiographs were taken at baseline and 3, 6 and 12 months after loading. Crestal bone‐level changes were assessed with digital subtraction radiographs. The effects of superstructure materials and implants were evaluated with one‐way anova and independent samples t‐test, respectively (α = 0·05). The mean crestal bone loss was found 0·483 mm in 3 months, 0·622 mm in 6 months and 0·816 mm in 12 months. Prosthetic materials were found to have greater effect (β = 0·575, P = 0·015) on crestal bone loss than implant systems (P > 0·05). The porcelain fused to BMA restorations showed higher crestal bone loss than NMA‐based restorations (P = 0·003) at 3 months, (P = 0·038), at 6 months and (P = 0·00) at 12 months; however, crestal bone loss differences between NMA and zirconia were not significant (P = 0·629) at 3 months, (P = 0·974) at 6 months and (P = 1) at 12 months. Within the limitations of this study, our results revealed that rather than the implant systems, prosthetic materials seemed to have an effective role on crestal bone.     

Improvement in patients with a TMD‐pain report. A 6‐month follow‐up study

Even though chronic TMD pain tends to persist in most patients, some chronic patients show improvement. It is largely unknown which factors contribute to the improvement of chronic pain. The aim of this study is to investigate which factors, from a biopsychosocial perspective, help to predict improvement in patients with a report of TMD pain. Methods: Subjects with a report of TMD pain were recruited in seven TMD clinics. They received a baseline questionnaire which included a wide range of possible predictors for improvement. After 6 months they received a follow‐up questionnaire which included a measure to determine which participants were ‘improved’ or ‘not improved’. To study which predictive variables were associated with improvement, multiple regression models were built. Results: From the 129 patients who responded to the baseline questionnaire, 100 patients also filled in the follow‐up questionnaire (85% women, mean age (years) ± s.d. = 46·0 ± 13·8). Fifty percentage of these subjects had improved at the 6‐month follow‐up. Pain duration was the strongest (negative) predictor for 6‐month improvement (P = 0·009). Also the number of care providers (P = 0·017) and the degree of hindrance on function (P = 0·045) helped to predict improvement. Conclusions: The duration of the TMD‐pain complaint, the number of care practitioners attended and the degree of hindrance on function (negatively) helped to predict 6‐month improvement. No evidence is found to support the role of psychological or social factors on the improvement in patients with a report of TMD pain.     

Effects of the Paced Auditory Serial Addition Task (PASAT) with different rates on autonomic nervous system responses and self‐reported levels of stress

To characterise self‐reported levels of stress and autonomic responses in healthy humans evoked by different rates of the Paced Auditory Serial Addition Task (PASAT). Fifteen participants performed PASATs with different rates (3·6‐, 2·4‐, 1·6‐ or 1·2‐s intervals) and a control task, in random order. Correct responses, self‐reported levels of stress and autonomic responses to the PASATs were estimated. Increased PASAT rates were associated with decreases in correct responses (P < 0·001) and increases in self‐reported levels of stress (P < 0·001). For autonomic responses, significant changes were seen in 10 variables during 2·4‐s PASAT compared with the respective baseline; however, significant differences in relative changes from baseline were found between the 2·4‐s PASAT and control task only for mean RR‐intervals (P < 0·001), systolic and diastolic blood pressure (P = 0·002 and P = 0·006) and cardiac output (P < 0·001). Regarding comparison between the four PASATs, significant differences in the relative changes from baseline were seen between the 3·6‐s PASAT and faster PASATs, for example mean RR‐intervals, high‐frequency power and respiration rate; however, there were no differences between the faster PASATs. The autonomic responses during the PASATs with different rates were quite similar for the faster PASATs (intervals < 2·4 s); however, the slowest 3·6‐s PASAT evoked significantly less self‐reported stress and autonomic arousal compared with the faster PASATs. Standardization of the PASAT rate may be important for studies on autonomic nervous system function and self‐reported measures of stress. Future studies may test more complex interactions between stress, autonomic responses and pain responses.     

Reliability,validity, and sex differences in a quantitative gag reflex measurement method

A reliable assessment method is required to manage the gag reflex. We tested the inter‐ and intra‐examiner reliability and validity of a quantitative measurement method and evaluated the differences between sexes. This study included 21 healthy adults (10 women, 11 men; mean age, 27.1 ± 9.9 years). An examiner inserted a standard saliva ejector slowly down the participant's throat to determine the maximum tolerance of the gag reflex; the insertion depth was used as an index of gag reflex. The reflex was measured by one examiner during two sessions (S1 and S3) and by a second examiner during one session (S2) under the same conditions. The galvanic skin response (GSR) and heart rate (HR) were recorded during each session to test the method validity. Data were analysed using the intraclass correlation coefficient (ICC), paired t test, and two‐way repeated‐measures analysis of variance. The ICC of the gag reflex measurements was 0.91 between S1 and S2, and 0.93 between S1 and S3. The GSR and HR increased significantly after the maximum tolerance of the reflex in S1, S2, and S3 (GSR: P < 0.001, P = 0.004, P = 0.001, respectively; HR: all, P < 0.001). Differences in the measurements according to sex and session were not significant. Our method exhibited excellent inter‐ and intra‐examiner reliability and was unaffected by the participants’ sex. Measurement revealed significant autonomic reactivity, which is common for this reflex. Consequently, this method may be used in clinical and laboratory‐based applications.     

The effect of mucosal cuff shrinkage around dental implants during healing abutment replacement

Soft tissue shrinkage during the course of restoring dental implants may result in biological and prosthodontic difficulties. This study was conducted to measure the continuous shrinkage of the mucosal cuff around dental implants following the removal of the healing abutment up to 60 s. Individuals treated with implant‐supported fixed partial dentures were included. Implant data – location, type, length, diameter and healing abutments' dimensions – were recorded. Mucosal cuff shrinkage, following removal of the healing abutments, was measured in bucco‐lingual direction at four time points – immediately after 20, 40 and 60 s. anova was used to for statistical analysis. Eighty‐seven patients (49 women and 38 men) with a total of 311 implants were evaluated (120 maxilla; 191 mandible; 291 posterior segments; 20 anterior segments). Two‐hundred and five (66%) implants displayed thick and 106 (34%) thin gingival biotype. Time was the sole statistically significant parameter affecting mucosal cuff shrinkage around dental implants (P < 0·001). From time 0 to 20, 40 and 60 s, the mean diameter changed from 4·1 to 4·07, 3·4 and 2·81 mm, respectively. The shrinkage was 1%, 17% and 31%, respectively. The gingival biotype had no statistically significant influence on mucosal cuff shrinkage (P = 0·672). Time required replacing a healing abutment with a prosthetic element should be minimised (up to 20/40 s), to avoid pain, discomfort and misfit.     

Effect of prosthetic restoration on oral health‐related quality of life in patients with shortened dental arches: a multicentre study

The aim of this multicentre prospective study was to investigate the effect of prosthetic restoration for missing posterior teeth in patients with shortened dental arches (SDAs). SDA patients with 2–12 missing occlusal units (a pair of occluding premolars corresponds to one unit, and a pair of occluding molars corresponds to two units) were consecutively recruited from seven university‐based dental hospitals in Japan. Patients chose no replacement of missing teeth or prosthetic treatment with removable partial dentures (RPDs) or implant‐supported fixed partial dentures (IFPDs). Oral health‐related quality of life (OHRQoL) was measured using the oral health impact profile (Japanese version – OHIP‐J) at baseline and follow‐up/post‐treatment evaluation. Of the 169 subjects who completed baseline evaluation, 125 subjects (mean age; 63·0 years) received follow‐up/post‐treatment evaluation. No‐treatment was chosen by 42% (53/125) of the subjects, and 58% (72/125) chose treatment with a RPD (n = 53) or an IFPD (n = 19). In the no‐treatment (NT) group, the mean OHIP summary score at baseline was similar to that at follow‐up evaluation (P = 0·69). In the treatment (TRT) group, the mean OHIP summary score decreased significantly after the RPD treatment (P = 0·002), and it tended to decrease, though not statistically significant (P = 0·18), after the IFPD treatment. The restoration of one occlusal unit was associated with a 1·2‐point decrease in OHIP summary score (P = 0·034). These results suggest that the replacement of missing posterior teeth with RPDs or IFPDs improved OHRQoL. Prosthetic restoration for SDAs may benefit OHRQoL in patients needing replacement of missing posterior teeth.     

Chlorhexidine gel and less difficult surgeries might reduce post‐operative pain,controlling for dry socket,infection and analgesic consumption: a split‐mouth controlled randomised clinical trial

Reports on post‐surgical pain are a few, controversial and flawed (by statistics and analgesic consumption). Besides, it is not known if chlorhexidine can reduce post‐extraction pain adjusting for its effect on prevention of infection and dry socket (DS). We assessed these. A total of 90 impacted mandibular third molars of 45 patients were extracted. Intra‐alveolar 0·2% chlorhexidine gel was applied in a split‐mouth randomised design to one‐half of the sockets. None of the included patients took antibiotics or analgesics afterwards. In the first and third post‐operative days, DS formation and pain levels were recorded. Predictive roles of the risk factors were analysed using fixed‐effects (classic) and multilevel (mixed‐model) multiple linear regressions (α = 0·05, β≤0·1). In the first day, pain levels were 5·56 ± 1·53 and 4·78 ± 1·43 (out of 10), respectively. These reduced to 3·22 ± 1·41 and 2·16 ± 1·40. Pain was more intense on the control sides [both P values = 0·000 (paired t‐test)]. Chlorhexidine had a significant pain‐alleviating effect (P = 0·0001), excluding its effect on DS and infection. More difficult surgeries (P = 0·0201) and dry sockets were more painful (P = 0·0000). Age had a marginally significant negative role (P = 0·0994). Gender and smoking had no significant impact [P ≥ 0·7 (regression)]. The pattern of pain reduction differed between dry sockets and healthy sockets [P = 0·0102 (anova )]. Chlorhexidine can reduce pain, regardless of its infection‐/DS‐preventive effects. Simpler surgeries and sockets not affected by alveolar osteitis are less painful. Smoking and gender less likely affect pain. The role of age was not conclusive and needs future studies.     

Temporomandibular disorder symptoms and their association with quality of life,emotional states and sleep quality in South‐East Asian youths

Population studies on the prevalence of temporomandibular disorders (TMD) and their associations with quality of life (QoL), emotional states and sleep quality in South‐East Asian youths are not available. This cross‐sectional study assessed the presence of TMD and their relationships to QoL, depression, anxiety, stress and sleep quality in a cohort of South‐East Asian adolescents/young adults. Three hundred and sixty‐two students from a polytechnic were enrolled in the study and completed an online questionnaire consisting of the Fonesca's Anamnestic Index (FAI), Oral Health Impact Profile for TMD (OHIP‐TMD), Depression, Anxiety and Stress Scales‐21 (DASS‐21) and Pittsburgh Sleep Quality Index. The FAI appraises TMD severity while OHIP‐TMD determines the effect of TMD on oral health‐related QoL. Statistical analysis was performed using chi‐square test for categorical data whilst one‐way ANOVA/post hoc Bonferroni's tests were employed for numerical scores (P < 0.05). Of the 244 participants who completed the questionnaires in their entirety (37 males; 207 females, mean age 20.1 ± 3.2 years), 32.4% had mild TMD, 9.4% had moderate TMD and 58.2% were TMD free. The total prevalence of TMD was 41.8% (n = 102) and most OHIP‐TMD domains including functional limitation (P = 0.000), physical pain (P = 0.000), handicapped (P = 0.000) and psychological discomfort (P = 0.001) showed significant differences in mean scores depending on TMD severity. A similar trend was observed for DASS‐21. The majority of participants with TMD (69.6%; n = 71) had poor sleep quality (P = 0.004). TMD appear to be prevalent in South‐East Asian youths with varying severity. Severity of TMD had some bearing on QoL, emotional states as well as sleep quality.     

Self‐reported gagging in dentistry: prevalence,psycho‐social correlates and oral health

Although gagging has a profound effect on the delivery of dental care, it is a relatively under‐investigated phenomenon. This study aimed to derive a prevalence estimate of gagging during dental treatment based on patient‐reported information, to determine some socio‐demographic and psychological correlates and to assess the relationship of gagging with self‐reported oral health and avoidance of dental care. Data were collected with a survey among Dutch twin families (n = 11 771). Estimated overall prevalence of gagging during dental treatment was 8·2% (95% CI 7·7–8·7). Patients' self‐report of gagging was found to be significantly associated with female sex, a lower level of education and higher levels of dental trait anxiety, gagging‐related fears (e.g. fear of objects in the mouth), anxious depression and neuroticism. Gagging also appeared to be significantly associated with untreated cavities, gingival bleeding and wearing full dentures, but not with avoidance of dental care. It can be concluded that individuals who report to gag during dental treatment are moderately dentally anxious, fear‐specific situations that can trigger a gagging response and, albeit visiting the dentist equally frequently, report to have a poorer oral health compared to those who do not gag.     

Management of shortened dental arches and periodontal health: 5‐year results of a randomised trial

In a multicentre randomised trial (German Research Association, grants DFG WA 831/2‐1 to 2‐6, WO 677/2‐1.1 to 2‐2.1.; controlled‐trials.com ISRCTN97265367), patients with complete molar loss in one jaw received either a partial removable dental prosthesis (PRDP) with precision attachments or treatment according to the SDA concept aiming at pre‐molar occlusion. The objective of this current analysis was to evaluate the influence of different treatments on periodontal health. Linear mixed regression models were fitted to quantify the differences between the treatment groups. The assessment at 5 years encompassed 59 patients (PRDP group) and 46 patients (SDA group). For the distal measuring sites of the posterior‐most teeth of the study jaw, significant differences were found for the plaque index according to Silness and Löe, vertical clinical attachment loss (CAL‐V), probing pocket depth (PPD) and bleeding on probing. These differences were small and showed a slightly more unfavourable course in the PRDP group. With CAL‐V and PPD, significant differences were also found for the study jaw as a whole. For CAL‐V, the estimated group differences over 5 years amounted to 0·27 mm (95% CI 0·05; 0·48; P = 0·016) for the study jaw and 0·25 mm (95% CI 0·05; 0·45; P = 0·014) for the distal sites of the posterior‐most teeth. The respective values for PPD were 0·22 mm (95% CI 0·03; 0·41; P = 0·023) and 0·32 mm (95% CI 0·13; 0·5; P = 0·001). It can be concluded that even in a well‐maintained patient group statistically significant although minor detrimental effects of PRDPs on periodontal health are measurable.     

Gagging Problem Assessment: a re‐evaluation

The Gagging Problem Assessment (GPA) is an instrument to evaluate dental gagging. Although the GPA seemed to be reliable and valid in a pilot study, a replication study with more subjects was needed. Based on the pilot study, the number of items was reduced, resulting in the revised version of the GPA (GPA‐R). The aims of this study were to replicate the reliability of the GPA‐R and to investigate the correlation between dental gagging and general anxiety. Dental gagging patients (n = 59) were compared with a control group (n = 17) at t0 and 3 weeks later. The ‘gagging group’ also filled in the SCL‐90 anxiety scale. Gagging‐specific homogenous domains and internal consistency were determined. Stability and distinguishing capacity of the GPA‐R were assessed. SCL‐90‐Anxiety scores were compared with standard values in a non‐clinical population. The GPA‐R patient part was able to reliably discriminate between the absence or the presence of dental gagging. However, the reliability of the GPA‐R‐dentist part was insufficient. The GPA‐R seems to be sensitive to subtle differences in acts of the dentists. To overcome these problems, more detailed and explicit instructions on how to use the GPA‐R should be formulated and more specific gagging stimuli should be included. The ‘gagging group’ reported ‘fear of choking’ significantly more often than the control group (P = 0·008). This finding might be important for the treatment of dental gagging. Considering the outcome of our study, development of a new diagnostic gagging tool needs another approach that focuses on gagging severity.     

The effect of implant placement in patients with either Kennedy class II and III on oral health‐related quality of life: a prospective clinical trial

There is little evidence of the effect of implants restored with fixed partial dentures on oral health‐related quality of life (OHRQoL) in partially edentulous Kennedy class II and III patients. The aim of this study was to determine the change in OHRQoL in Kennedy classification II and III patients treated with a two‐implant‐supported fixed dental prosthesis (FDP). Kennedy class II and III patients received dental implants and an FDP. Oral health‐related quality of life was measured by administration of the Oral Health Impact Profile‐14 (OHIP‐14NL) questionnaire at intake (T1), 2 weeks after surgery (T2) and after 1 year of loading (T3). The mean OHIP score at T1 was 6·5 ± 1·2, 2·4 ± 1·0 at T2, and 0·9 ± 0·3 at T3. There was a statistically significant difference between T1 and T2 (P = 0·002) and T1 and T3 (P < 0·001) but not between T2 and T3 (P = 0·407). The OHIP score in Kennedy II patients decreased from 4·8 ± 3·2 at T1 to 1·5 ± 2·0 at T2 and 1·1 ± 1·8 at T3, and that in Kennedy III patients decreased from 8·9 ± 9·6 at T1 to 3·6 ± 8·9 at T2 and 0·8 ± 2·2 at T3. There were no statistically significant differences in the reductions in Kennedy II and III patients. Oral health‐related quality of life changed positively in patients treated with implants and an FDP in both groups. There was no change in OHRQoL between the times of implant placement and FDP placement.     

Recognition of patient‐reported impairment in oral aesthetics

The objectives of this study were to investigate the degree of effective recognition by professionals of patient‐estimated oral aesthetic impairment and the most reliable aspects in such recognition. Participants consisted of 95 patients with partial dentition in need of prosthodontic replacements. The oral aesthetics was professionally evaluated using the Prosthetic Esthetic Index (PEI), compiling 13 aesthetic aspects and an overall evaluation. The patient‐reported impairment was evaluated using the Oral Health Impact Profile Aesthetic (OHIP‐Aes) and the Oral Esthetic Scale (OES). Background variables were as follows: gender, age, work situation, education level, marital status, number and location of teeth, wearing a removable dental prosthesis (RDP) and smile line. A significant correlation was found between the overall professional evaluation and the OHIP‐Aes score (R = 0·43, P < 0·05), the OES score (R = 0·46, P < 0·05) and the overall patient evaluation (0·35, P < 0·05). Correlations of the 13 specific aspects of the PEI with the patient‐reported evaluations were generally small to moderate: the aspect ‘discoloration of the teeth’ showed the highest correlation. The multivariate analyses showed that up to 57% of the patient‐reported impairment could be explained by the professionally evaluated oral aesthetic in combination with background variables. Discoloration of the teeth was the greatest explanatory variable, but also dental arch symmetry, and position and colour of the teeth were significant aspects. A high percentage of the patient‐reported aesthetic impairment can be recognised by the professionals. The most reliable aspect is discoloration of the teeth, but also dental arch symmetry, and the position and colour of the teeth are important for recognising the aesthetic impairment.     

Psychometric properties of the Dutch version of the Orofacial Esthetic Scale (OES‐NL) in dental patients with and without self‐reported tooth wear

The aim of this study was to test the psychometric properties of the Dutch version of the Orofacial Esthetic Scale (OES) in dental patients with and without self‐reported tooth wear. The English version of the OES was translated into Dutch, following established guidelines for cross‐cultural adaptation of health‐related quality of life measures. The reliability of the resulting OES‐NL was tested in a test–retest study on 343 subjects; its validity was tested with the use of convergent validity on 582 subjects. The test–retest reliability of the OES‐NL showed intra‐class correlation coefficients (ICC) that ranged from 0·76 to 0·82, which can be qualified as excellent. The Cronbach's alpha revealed that the overall internal consistency of the scale was good (α = 0·89). Convergent validity was confirmed by the association between the OES‐NL summary scores and three questions of the Dutch version of the Oral Health Impact Profile (OHIP‐NL). The calculated Spearman's rank correlation coefficients ranged from −0·43 to −0·54 and were all significant (P < 0·001). The Dutch version of the Orofacial Esthetic Scale (OES‐NL) showed good psychometric properties, making it suitable for the assessment of self‐perceived aesthetics in Dutch dental patients with and without self‐reported tooth wear.     

Prophylactic antibiotic regimen and dental implant failure: a meta‐analysis

The aim of this meta‐analysis was to investigate whether there are any positive effects of prophylactic antibiotic regimen on implant failure rates and post‐operative infection when performing dental implant treatment in healthy individuals. An electronic search without time or language restrictions was undertaken in March 2014. Eligibility criteria included clinical human studies, either randomised or not. The search strategy resulted in 14 publications. The I² statistic was used to express the percentage of the total variation across studies due to heterogeneity. The inverse variance method was used with a fixed‐ or random‐effects model, depending on the heterogeneity. The estimates of relative effect were expressed in risk ratio (RR) with 95% confidence interval. Six studies were judged to be at high risk of bias, whereas one study was considered at moderate risk, and six studies were considered at low risk of bias. The test for overall effect showed that the difference between the procedures (use versus non‐use of antibiotics) significantly affected the implant failure rates (P = 0·0002), with a RR of 0·55 (95% CI 0·41–0·75). The number needed to treat (NNT) to prevent one patient having an implant failure was 50 (95% CI 33–100). There were no apparent significant effects of prophylactic antibiotics on the occurrence of post‐operative infections in healthy patients receiving implants (P = 0·520). A sensitivity analysis did not reveal difference when studies judged as having high risk of bias were not considered. The results have to be interpreted with caution due to the presence of several confounding factors in the included studies.     

Mastication and jaw motion of partially edentulous patients are affected by different implant‐based prostheses

The main goal of prosthetic treatment is to restore masticatory function. However, insufficient evidence supports the recommendation of one specific prosthetic intervention for partially edentulous patients. Function after the use of three different prostheses by the same partially edentulous subject. Mastication was assessed in 12 subjects (mean age 62·6 ± 7·8 years) after they had used removable partial dentures (RPDs), implant‐supported partial dentures (IRPDs) and implant‐fixed partial dentures (IFPDs). Masticatory ability (MA) was estimated by visual analogue scale questionnaire, while the mandibular chewing motion was evaluated by kinesiographic device, representing an objective measurement of masticatory function. Data were analysed by repeated‐measures anova followed by Tukey–Kramer (P < 0·05). MA improved after IRPD and IFPD use (P < 0·05). Opening, closing and total cycle time duration were reduced after both IRPD and IFPD use (P < 0·05), irrespectively the implant prosthesis type. IFPDs and IRPDs restore the masticatory function of partially edentulous patients better than RPDs.     

Factors associated with pain induced by orthodontic separators

Pain resulting from the application of orthodontic forces varies markedly across individuals. The reasons of this variability are still largely unknown. To investigate factors that may be associated with orthodontic pain following the application of orthodontic separators. One hundred and seven participants were screened for pain response over 48 h following placement of orthodontic elastomeric separators. The highest (n = 10) and lowest (n = 10) pain responders were identified, and data collected on tooth pain sensitivity to electrical stimulation in conjunction with using the Pain Catastrophising Scale (PCS), Dental Anxiety Scale (DAS) and cold pressor test (CPT). There were statistically significant differences between high‐ and low‐pain responders in catastrophising score (P ≤ 0·023). For every PCS magnification score of 1 unit higher, the relative risk of being a high‐pain responder was 1·6 (P = 0·002); those scoring higher on helplessness had a lower risk of being so. DAS scores of high‐pain responders were twice as high as those of low‐pain responder (P = 0·043). During the first 2 min of CPT, the high‐pain responders experienced more pain than the low‐pain responders (P ≤ 0·029). Tooth pain thresholds did not differ between the two different pain responder groups. Pain catastrophising, dental anxiety and cold sensitivity appear to modify the pain experienced following placement of orthodontic separators. Further research is needed to determine the validity of screening questions to identify at‐risk patients prior to commencing orthodontic treatment.