Current landmarks for gingival thickness evaluation in maxillary anterior teeth: a systematic review.

OBJECTIVES: To identify and report the current landmarks used for measuring gingival thickness (GT) in healthy maxillary anterior teeth. MATERIAL AND METHODS: The protocol of this Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) 2020-compliant systematic review was registered in PROSPERO. A literature search was conducted to identify articles that met the eligibility criteria published up to 2022. The methods of assessing gingival thickness and the landmarks adopted on the studies were described. Primary outcomes were identified, and the frequency of reporting in the selected articles was calculated. Additionally, risk-of-bias assessments were performed for individual articles. RESULTS: Fifty-eight articles (34 with low risk of bias and 24 with medium risk of bias) were selected. A total of 3638 individuals had their gingival thickness measured. Thirty-nine different landmarks were adopted in the studies. Fifty-six articles with 22 landmarks were included in the meta-analysis. A higher heterogeneity was found between the studies (GT ranged from 0.48 to 2.59 mm, mean GT 1.074; 95% CI: 1.024-1.104). The 3 most used landmarks were 2 mm from gingival margin (10 studies, mean GT 1.170 mm, 95% CI: 1.085-1.254), bone crest (9 studies, mean GT 1.01 mm; 95% CI: 0.937-1.083), and cemento-enamel junction (7 studies, mean GT 1.172 mm; 95% CI: 1.105, 1.239). CONCLUSIONS: Within the limits of this study, a large heterogeneity in GT was found, and there was no consensus on the ideal landmark for GT measurement. CLINICAL RELEVANCE: The landmark 2 mm from gingival margin, located at attached gingiva, can be used for GT measurement by clinical and image-based devices. This is an important step for a quantitative instead of a qualitative evaluation of phenotypes.

The relationship between tomographic sagittal root position of maxillary anterior teeth and the bone housing.

STATEMENT OF PROBLEM: In a prosthetically driven treatment plan, the tomographic sagittal root position in relation to the bone housing is an important factor in the decision-making process for immediate implant placement. However, other important parameters must be considered in the bone housing of each tooth, including the alveolar ridge dimensions, the buccal and the palatal bone thickness, and the root dimensions. PURPOSE: The purpose of this clinical study was to evaluate the relationship between the sagittal root position of maxillary anterior teeth and the bone housing. MATERIALS AND METHODS: A total of 420 maxillary anterior teeth were analyzed in 70 participants. The tomographic scans were classified as sagittal root position classes I, II, III, and IV. Measurements included buccal and palatal bone thickness, alveolar ridge height, alveolar ridge width, apical bone height, root length, and root width. The Pearson correlation, ANOVA, and Tukey post hoc tests were used to determine statistically significant differences (α=0.05). RESULTS: The sagittal root position distribution was 65.2%, 9.3%, 0.7%, and 24.8% for classes I, II, III, and IV, respectively. Bone housing measurements were significantly different in relation to the 4 sagittal root position classes (P<.05), except for alveolar ridge height. Post hoc analysis showed that, in class I, buccal bone thickness and alveolar bone height were significantly low, whereas root length and palatal bone thickness were high. The higher buccal bone thickness was found in class II, and lower alveolar ridge width and palatal bone thickness in class IV. These measurements in tooth groups were also significantly different over the sagittal root position classes (P<.05). The buccal bone thickness, palatal bone thickness, and alveolar ridge width presented different levels of correlation with alveolar ridge width over the sagittal root position classes. The buccal bone thickness and palatal bone thickness were weakly correlated in class I (r=0.163) and IV (r=0.222). CONCLUSIONS: Bone housing measurements were significantly different in relation to the sagittal root position of maxillary anterior teeth.

Tomographic sagittal root position in relation to maxillary anterior bone housing in a Brazilian population.

Purpose: This cross-sectional study evaluated and categorized the tomographic sagittal root position (SRP) of the maxillary anterior teeth in a Brazilian population. Materials and Methods: Cone-beam computed tomographic scans of 420 maxillary anterior teeth of 70 patients (35 men and 35 women, mean age 25.2±5.9 years) were evaluated. The SRP was classified as class I, II, III, or IV. In class I, the root is positioned against the buccal cortical plate; in class II, the root is centered in the middle of the alveolar housing; in class III, the root is positioned against the palatal cortical plate; and in class IV, at least two-thirds of the root engage both the buccal and palatal cortical plates. Results: In total, 274 teeth (65.2%) were class I, 39 (9.3%) were class II, 3 (0.7%) were class III, and 104 (24.8%) were class IV. The frequency distribution over the teeth groups was different from the overall analysis. Important differences were found in the frequencies of classes I, II, and IV compared to other populations. Sex was not associated with the SRP classes (P=0.307). Age distribution was significantly different over the classes (P=0.004). Conclusion: The findings of this study on the distribution of SRP classes among the Brazilian population compared to other populations demonstrate that the SRP should be analyzed on a case-by-case basis for an accurate treatment plan in the maxillary anterior area.

Relationship between anterior maxillary tooth sagittal root position and periodontal phenotype: a clinical and tomographic study.

OBJECTIVES: To evaluate the relationship between the tomographic sagittal root position (SRP) of maxillary anterior teeth and periodontal phenotype (PP). MATERIAL AND METHODS: Seventy volunteers (420 teeth) were evaluated. Clinical and photographic exams included the evaluation of gingival phenotype (GP) by transparency of the periodontal probe, keratinized tissue width (KTW), gingival architecture, tooth shape, and papilla height (PH). Soft tissue tomographic scan (ST-CBCT) measurements included the SRP classification, GP, gingival thickness in the tissue zone (GT-TZ) and in the bone zone (GT-BZ), buccal bone thickness (BBT), and the distances from the gingival margin and from cementoenamel junction to the buccal bone crest (GM-BBC and CEJ-BBC). Kruskal-Wallis test and a linear regression analysis model were used. RESULTS: The frequency of SRP over the 420 teeth was 65.2% (class I), 9.3% (class II), 0.7% (class III), and 24.8% (class IV). Linear regression analysis showed that SRP is related to PP (p < 0.05). Significantly different measurements of PP parameters were found in SRP classes. The higher and lower GT and BBT were found in classes II and I, respectively. Class IV presented the highest KTW, PH, CEJ-BBC, and GM-BBC. Central incisors (CI) classes I and II were most frequently square-shaped, while 89% of CI Class IV were triangular-shaped. CONCLUSION: The SRP of maxillary anterior teeth is related to periodontal phenotype. CLINICAL RELEVANCE: Clinical and ST-CBCT individual analysis of PP and SRP may be helpful for an esthetic and functional treatment plan based on soft and hard tissue thickness and tooth positioning.

Clinical outcomes of botulinum toxin type A injections in the management of primary bruxism in adults: A systematic review.

STATEMENT OF PROBLEM: Botulinum toxin has been used for various therapeutic and esthetic purposes for nearly 4 decades and has shown positive outcomes in patients with bruxism. However, the effectiveness of botulinum toxin injections as an alternative to traditional therapies in the management of primary bruxism is still unclear. PURPOSE: The purpose of this systematic review was to analyze the clinical outcomes of the use of botulinum toxin type A injections in the management of primary bruxism in adults. MATERIAL AND METHODS: Databases such as PubMed, Web of Science, Scopus, LILIACS, Cochrane Library, and Open Grey Literature were searched without language or date restrictions until October 6, 2019. Using Mendeley Desktop software to organize the references, 2 independent researchers selected the published clinical studies (Study type) on the improvement of symptoms (Outcome) in human adults with primary bruxism (Participants/Population) who received botulinum toxin type A injections (Intervention), placebo injections, saline injections, no injections, or other treatments (Comparator(s)/Control) for the management of bruxism. RESULTS: A total of 601 references were initially obtained from the 6 databases. Six randomized clinical trials and 4 case series were selected and critically appraised according to the Fowkes and Fulton guidelines. Heterogeneity among the studies did not allow for a meta-analysis. All studies supported the efficacy and safety of botulinum toxin injections in reducing the symptoms of primary bruxism. CONCLUSIONS: Botulinum toxin type A injections are effective in the treatment of the symptoms of primary bruxism in adults. Randomized clinical trials are still needed to establish a protocol for using botulinum toxin as an alternative to traditional therapies in the management of primary bruxism.

Systematic review of the effect of probiotics on experimental gingivitis in humans.

Probiotic therapy is a viable alternative to chlorhexidine, a widely used antiseptic in dentistry that produces significant adverse effects. This systematic review aimed to analyze the effects of probiotics on experimental gingivitis in humans. Two independent reviewers conducted a comprehensive literature search until March 2019. Randomized clinical trials and controlled clinical trials were selected. Outcome data were extracted and critically analyzed. A total of five articles were included in the qualitative synthesis. No meta-analysis could be conducted due to the heterogeneity of the selected studies. The use of probiotics showed a slight improvement in clinical parameters. Changes in gingival crevicular fluid volume were lower in the presence of the probiotic than in the placebo group. All the studies showed that the immediate, positive effects of probiotics during the period of discontinued mechanical oral hygiene were due to the modulation of the host response, not the anti-plaque effect. Investigators should conduct randomized clinical trials to elucidate the mechanisms of probiotic action and develop improved delivery systems.