Clinical performance of implant-supported single hybrid abutment crown restoration: A systematic review and meta-analysis.

PURPOSE: To investigate survival rates and technical and biological complications of one-piece screw-retained hybrid abutments in implant-supported single crowns (SCs). STUDY SELECTION: An electronic search was performed on five databases for clinical studies involving implant-supported single hybrid abutment crowns constructed using titanium-base (Ti base) abutments, with at least 12 months of follow-up. The RoB 2, Robins-I, and JBI tools were used to assess the risk of bias for the different study types. Success, survival, and complication rates were calculated, and a meta-analysis was performed to obtain a pooled estimate. Peri-implant health parameters were extracted and analyzed. RESULTS: 22 records (20 studies) were included in this analysis. Direct comparisons between screw-retained hybrid abutment SCs and cemented SCs showed no significant differences in the 1-year survival and success rates. For SCs using a hybrid abutment crown design, their 1-year survival rate was 100% (95% CI: 100%-100%, I2 = 0.0%, P = 0.984), and a success rate of 99% (95% CI: 97%-100%, I2 = 50.3%, P = 0.023) was calculated. No confounding variables significantly affected the estimates. The individual technical complication rate was low at 1-year follow-up. The estimated incidence of all types of complications in hybrid abutment SCs is less than 1%. CONCLUSIONS: Within the limitations of this study, implant-supported SCs using a hybrid abutment crown design showed favorable short-term clinical outcomes. Additional well-designed clinical trials with at least a 5-year observation period are required to confirm their long-term clinical performance.

Prevalence and morphological characteristics of disto-lingual roots in mandibular first molars: a cone beam CT study with diagnostic and therapeutic implications.

OBJECTIVES: High prevalence of disto-lingual roots (DLR) at the mandibular molar in Chinese can complicate the management of periodontitis. This study assessed the prevalence and morphological features of mandibular first molar DLR and furcation entrances in a Hong Kong population by analysis of cone beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT including the mandibular 1st molar region were identified from the Prince Philip Dental Hospital archive and analyzed by a single investigator. Morphologic features and location of DLR were studied and presented as 95% confidence intervals. RESULTS: A total of 398 CBCTs with 716 mandibular first molars were analyzed. The prevalence of DLRs in mandibular first molars on subject based was 20.1% (95% C.I. 16.2-24%). DLR was located 44.5° ± 8.9° (95% C.I. 42.8-46.1°) to the mid-lingual of the mandibular first molar, with a bucco-lingual width 3.3 mm ± 0.5 mm (95% C.I. 3.2-3.4 mm). The mesial furcation entrance was located 4.0 mm ± 0.9 mm (95% C.I. 3.8-4.2 mm) apical to the cemento-enamel junction (CEJ) while the distal was 5.2 mm ± 1.3 mm (95% C.I. 5.0-5.4 mm) from the CEJ. The surface area of the DLR was 106.9 mm2 ± 41.2 mm2 (95% C.I. 98.9-114.8 mm2). CONCLUSIONS: Chinese population has a high prevalence of DLRs. The present information is critical for understanding the morphological features of DLR and guide diagnosis and treatment of stage III periodontitis as well as for secondary prevention and supportive care of stage II periodontitis. CLINICAL RELEVANCE: Little is known about the location and morphology of disto-lingual roots of mandibular 1st molars, yet they are frequently present in patients with Chinese ethnic background, thus complicating diagnosis and treatment. The present study utilized CBCT to analyze the prevalence and morphological features of the mandibular first molar DLR and furcation entrance. It is the first study reporting on the position of the DLR, degree of separation of the furcation, and the surface area of the DLR.

Aesthetic assessment after root coverage of multiple adjacent recessions with coronally advanced flap with adjunctive collagen matrix or connective tissue graft: Randomized clinical trial.

BACKGROUND: Few studies have looked at professional assessment or patient perception of aesthetics after root coverage procedures. The addition of connective tissue grafts (CTG) seems to improve aesthetic outcomes. The objective of this a priori analysis was to compare aesthetics after addition of CTG or a collagen matrix (CMX) to coronally advanced flap (CAF). METHODS: Two independent, trained and calibrated assessors analysed baseline and 6-month post-operative Images from 183 subjects with 475 recessions from a previously reported multicentre multinational randomized clinical trial. The root coverage aesthetic score (RES) was assessed in its five constituent components after assessing the suitability of images blindly with regard to treatment assignment and centre. Data were analysed at the tooth and subject level. RESULTS: One hundred and fifty-five subjects (81 CTG) and 393 teeth (207 CTG) were included in the analysis. CTG control subjects had higher total RES scores (mean adjusted difference of 1.3 ± 0.8 RES units, p = 0.002). Analyses of RES subcomponents showed that the CTG group had higher scores in terms of gingival margin position but that better marginal tissue contour (OR 3.0, 95% CI 1.2-7.7) and soft tissue texture (OR 3.3, 95% CI 1.9-5.8) was observed for the CMX group. No significant differences were observed for mucogingival alignment and gingival colour. CONCLUSION: Better overall RES scores were observed for the CTG group. Better marginal tissue texture and marginal contour were observed in the CMX group. More research and development is needed to optimize materials to be used in conjunction with CAF to improve root coverage without negatively affecting tissue texture and marginal contour.

The impact of dental neglect on oral health: a population based study in Hong Kong.

OBJECTIVE: The aim of this study was to assess dental neglect (DN) among Hong Kong citizens, to identify socio-demographic variations in DN and to determine the association between DN and oral health (self-reported). DESIGN: Cross sectional population based study involving a random sample of 800 Hong Kong Chinese adults. METHOD: Telephone interview incorporating the dental neglect scale, assessment of self-reported oral health including an oral health related quality of life measure. RESULTS: The response rate was 70% (556/800). Mean dental neglect score of the population was 14.81 (S.D. 3.62) [possible range 6 to 30]. Most commonly, people were neglectful of using professional dental health care. Socio-demographic disparities in DN were apparent, in relation to age (P < 0.05), income (P < 0.05) and educational attainment (P < 0.05). DN was associated with self-reported oral health: denture status (P < 0.05), number of teeth possessed (P < 0.05) and oral health related quality of life (P < 0.05). CONCLUSION: Dental neglect is widespread in Hong Kong, particularly neglect of professional dental care. Socio-demographic disparities in dental neglect were apparent. Dental neglect is associated with self-reported oral health status including how oral health impacts on life quality. These findings have implications in understanding the impact of dental neglect.